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Sample records for age-related cognitive change

  1. Shared and Unique Genetic and Environmental Influences on Aging-Related Changes in Multiple Cognitive Abilities

    ERIC Educational Resources Information Center

    Tucker-Drob, Elliot M.; Reynolds, Chandra A.; Finkel, Deborah; Pedersen, Nancy L.

    2014-01-01

    Aging-related declines occur in many different domains of cognitive function during middle and late adulthood. However, whether a global dimension underlies individual differences in changes in different domains of cognition and whether global genetic influences on cognitive changes exist is less clear. We addressed these issues by applying…

  2. Cognitive performance and age-related changes in the hippocampal proteome

    PubMed Central

    Freeman, Willard M.; VanGuilder, Heather D.; Bennett, Colleen; Sonntag, William E.

    2008-01-01

    Declining cognitive performance is associated with increasing age, even in the absence of overt pathological processes. We and others have reported that declining cognitive performance is associated with age-related changes in brain glucose utilization, long-term potentiation and paired-pulse facilitation, protein expression, neurotransmitter levels, and trophic factors. However, it is unclear whether these changes are causes or symptoms of the underlying alterations in dendritic and synaptic morphology that occur with age. In this study, we examined the hippocampal proteome for age- and cognition-associated changes in behaviorally stratified young and old rats, using 2-DIGE and MS/MS-MS. Comparison of old cognitively intact with old cognitively impaired animals revealed additional changes that would not have been detected otherwise. Interestingly, not all age-related changes in protein expression were associated with cognitive decline, and distinct differences in protein expression were found when comparing old cognitively intact with old cognitively impaired rats. A large number of protein changes with age were related to the glycolysis/gluconeogenesis pathway. In total, the proteomic changes suggest that age-related alterations act synergistically with other perturbations to result in cognitive decline. This study also demonstrates the importance of examining behaviorally-defined animals in proteomic studies, as comparison of young to old animals regardless of behavioral performance would have failed to detect many cognitive impairment-specific protein expression changes evident when behavioral stratification data was used. PMID:19135133

  3. Cognitive Abilities Explaining Age-Related Changes in Time Perception of Short and Long Durations

    ERIC Educational Resources Information Center

    Zelanti, Pierre S.; Droit-Volet, Sylvie

    2011-01-01

    The current study investigated how the development of cognitive abilities explains the age-related changes in temporal judgment over short and long duration ranges from 0.5 to 30 s. Children (5- and 9-year-olds) as well as adults were given a temporal bisection task with four different duration ranges: a duration range shorter than 1 s, two…

  4. Age-related changes in dentate gyrus cell numbers, neurogenesis, and associations with cognitive impairments in the rhesus monkey

    PubMed Central

    Ngwenya, Laura B.; Heyworth, Nadine C.; Shwe, Yamin; Moore, Tara L.; Rosene, Douglas L.

    2015-01-01

    The generation of new neurons in the adult mammalian brain is well-established for the hippocampal dentate gyrus (DG). However, the role of neurogenesis in hippocampal function and cognition, how it changes in aging, and the mechanisms underlying this are yet to be elucidated in the monkey brain. To address this, we investigated adult neurogenesis in the DG of 42 rhesus monkeys (39 cognitively tested) ranging in age from young adult to the elderly. We report here that there is an age-related decline in proliferation and a delayed development of adult neuronal phenotype. Additionally, we show that many of the new neurons survive throughout the lifetime of the animal and may contribute to a modest increase in total neuron number in the granule cell layer of the DG over the adult life span. Lastly, we find that measures of decreased adult neurogenesis are only modestly predictive of age-related cognitive impairment. PMID:26236203

  5. Age-related changes in dentate gyrus cell numbers, neurogenesis, and associations with cognitive impairments in the rhesus monkey.

    PubMed

    Ngwenya, Laura B; Heyworth, Nadine C; Shwe, Yamin; Moore, Tara L; Rosene, Douglas L

    2015-01-01

    The generation of new neurons in the adult mammalian brain is well-established for the hippocampal dentate gyrus (DG). However, the role of neurogenesis in hippocampal function and cognition, how it changes in aging, and the mechanisms underlying this are yet to be elucidated in the monkey brain. To address this, we investigated adult neurogenesis in the DG of 42 rhesus monkeys (39 cognitively tested) ranging in age from young adult to the elderly. We report here that there is an age-related decline in proliferation and a delayed development of adult neuronal phenotype. Additionally, we show that many of the new neurons survive throughout the lifetime of the animal and may contribute to a modest increase in total neuron number in the granule cell layer of the DG over the adult life span. Lastly, we find that measures of decreased adult neurogenesis are only modestly predictive of age-related cognitive impairment. PMID:26236203

  6. Guidelines for the Evaluation of Dementia and Age-Related Cognitive Change

    ERIC Educational Resources Information Center

    American Psychologist, 2012

    2012-01-01

    Dementia in its many forms is a leading cause of functional limitation among older adults worldwide and will continue to ascend in global health importance as populations continue to age and effective cures remain elusive. The following guidelines were developed for psychologists who perform evaluations of dementia and age-related cognitive…

  7. Inspection Time and Cognitive Abilities in Twins Aged 7 to 17 Years: Age-Related Changes, Heritability and Genetic Covariance

    ERIC Educational Resources Information Center

    Edmonds, Caroline J.; Isaacs, Elizabeth B.; Visscher, Peter M.; Rogers, Mary; Lanigan, Julie; Singhal, Atul; Lucas, Alan; Gringras, Paul; Denton, Jane; Deary, Ian J.

    2008-01-01

    We studied the age-related differences in inspection time and multiple cognitive domains in a group of monozygotic (MZ) and dizygotic (DZ) twins aged 7 to 17 years. Data from 111 twin pairs and 19 singleton siblings were included. We found clear age-related trends towards more efficient visual information processing in older participants. There…

  8. Age-related changes in the cerebral substrates of cognitive procedural learning.

    PubMed

    Hubert, Valérie; Beaunieux, Hélène; Chételat, Gaël; Platel, Hervé; Landeau, Brigitte; Viader, Fausto; Desgranges, Béatrice; Eustache, Francis

    2009-04-01

    Cognitive procedural learning occurs in three qualitatively different phases (cognitive, associative, and autonomous). At the beginning of this process, numerous cognitive functions are involved, subtended by distinct brain structures such as the prefrontal and parietal cortex and the cerebellum. As the learning progresses, these cognitive components are gradually replaced by psychomotor abilities, reflected by the increasing involvement of the cerebellum, thalamus, and occipital regions. In elderly subjects, although cognitive studies have revealed a learning effect, performance levels differ during the acquisition of a procedure. The effects of age on the learning of a cognitive procedure have not yet been examined using functional imaging. The aim of this study was therefore to characterize the cerebral substrates involved in the learning of a cognitive procedure, comparing a group of older subjects with young controls. For this purpose, we performed a positron emission tomography activation study using the Tower of Toronto task. A direct comparison of the two groups revealed the involvement of a similar network of brain regions at the beginning of learning (cognitive phase). However, the engagement of frontal and cingulate regions persisted in the older group as learning continued, whereas it ceased in the younger controls. We assume that this additional activation in the older group during the associative and autonomous phases reflected compensatory processes and the fact that some older subjects failed to fully automate the procedure. PMID:18537110

  9. Age-Related Changes in Cognitive Processing of Moral and Social Conventional Violations

    ERIC Educational Resources Information Center

    Lahat, Ayelet; Helwig, Charles C.; Zelazo, Philip David

    2012-01-01

    Moral and conventional violations are usually judged differently: Only moral violations are treated as independent of social rules. To investigate the cognitive processing involved in the development of this distinction, undergraduates (N = 34), adolescents (N = 34), and children (N = 14) read scenarios presented on a computer that had 1 of 3…

  10. Working memory in middle-aged males: age-related brain activation changes and cognitive fatigue effects.

    PubMed

    Klaassen, Elissa B; Evers, Elisabeth A T; de Groot, Renate H M; Backes, Walter H; Veltman, Dick J; Jolles, Jelle

    2014-02-01

    We examined the effects of aging and cognitive fatigue on working memory (WM) related brain activation using functional magnetic resonance imaging. Age-related differences were investigated in 13 young and 16 middle-aged male school teachers. Cognitive fatigue was induced by sustained performance on cognitively demanding tasks (compared to a control condition). Results showed a main effect of age on left dorsolateral prefrontal and superior parietal cortex activation during WM encoding; greater activation was evident in middle-aged than young adults regardless of WM load or fatigue condition. An interaction effect was found in the dorsomedial prefrontal cortex (DMPFC); WM load-dependent activation was elevated in middle-aged compared to young in the control condition, but did not differ in the fatigue condition due to a reduction in activation in middle-aged in contrast to an increase in activation in the young group. These findings demonstrate age-related activation differences and differential effects of fatigue on activation in young and middle-aged adults.

  11. Consequences of Age-Related Cognitive Declines

    PubMed Central

    Salthouse, Timothy

    2013-01-01

    Adult age differences in a variety of cognitive abilities are well documented, and many of those abilities have been found to be related to success in the workplace and in everyday life. However, increased age is seldom associated with lower levels of real-world functioning, and the reasons for this lab-life discrepancy are not well understood. This article briefly reviews research concerned with relations of age to cognition, relations of cognition to successful functioning outside the laboratory, and relations of age to measures of work performance and achievement. The final section discusses several possible explanations for why there are often little or no consequences of age-related cognitive declines in everyday functioning. PMID:21740223

  12. Intrinsic Hippocampal Excitability Changes of Opposite Signs and Different Origins in CA1 and CA3 Pyramidal Neurons Underlie Aging-Related Cognitive Deficits.

    PubMed

    Oh, M Matthew; Simkin, Dina; Disterhoft, John F

    2016-01-01

    Aging-related cognitive deficits have been attributed to dysfunction of neurons due to failures at synaptic or intrinsic loci, or both. Given the importance of the hippocampus for successful encoding of memory and that the main output of the hippocampus is via the CA1 pyramidal neurons, much of the research has been focused on identifying the aging-related changes of these CA1 pyramidal neurons. We and others have discovered that the postburst afterhyperpolarization (AHP) following a train of action potentials is greatly enlarged in CA1 pyramidal neurons of aged animals. This enlarged postburst AHP is a significant factor in reducing the intrinsic excitability of these neurons, and thus limiting their activity in the neural network during learning. Based on these data, it has largely been thought that aging-related cognitive deficits are attributable to reduced activity of pyramidal neurons. However, recent in vivo and ex vivo studies provide compelling evidence that aging-related deficits could also be due to a converse change in CA3 pyramidal neurons, which show increased activity with aging. In this review, we will incorporate these recent findings and posit that an interdependent dynamic dysfunctional change occurs within the hippocampal network, largely due to altered intrinsic excitability in CA1 and CA3 hippocampal pyramidal neurons, which ultimately leads to the aging-related cognitive deficits. PMID:27375440

  13. Intrinsic Hippocampal Excitability Changes of Opposite Signs and Different Origins in CA1 and CA3 Pyramidal Neurons Underlie Aging-Related Cognitive Deficits

    PubMed Central

    Oh, M. Matthew; Simkin, Dina; Disterhoft, John F.

    2016-01-01

    Aging-related cognitive deficits have been attributed to dysfunction of neurons due to failures at synaptic or intrinsic loci, or both. Given the importance of the hippocampus for successful encoding of memory and that the main output of the hippocampus is via the CA1 pyramidal neurons, much of the research has been focused on identifying the aging-related changes of these CA1 pyramidal neurons. We and others have discovered that the postburst afterhyperpolarization (AHP) following a train of action potentials is greatly enlarged in CA1 pyramidal neurons of aged animals. This enlarged postburst AHP is a significant factor in reducing the intrinsic excitability of these neurons, and thus limiting their activity in the neural network during learning. Based on these data, it has largely been thought that aging-related cognitive deficits are attributable to reduced activity of pyramidal neurons. However, recent in vivo and ex vivo studies provide compelling evidence that aging-related deficits could also be due to a converse change in CA3 pyramidal neurons, which show increased activity with aging. In this review, we will incorporate these recent findings and posit that an interdependent dynamic dysfunctional change occurs within the hippocampal network, largely due to altered intrinsic excitability in CA1 and CA3 hippocampal pyramidal neurons, which ultimately leads to the aging-related cognitive deficits. PMID:27375440

  14. Neuroanatomical Substrates of Age-Related Cognitive Decline

    ERIC Educational Resources Information Center

    Salthouse, Timothy A.

    2011-01-01

    There are many reports of relations between age and cognitive variables and of relations between age and variables representing different aspects of brain structure and a few reports of relations between brain structure variables and cognitive variables. These findings have sometimes led to inferences that the age-related brain changes cause the…

  15. Age-related changes in brain activity are specific for high order cognitive processes during successful encoding of information in working memory

    PubMed Central

    Pinal, Diego; Zurrón, Montserrat; Díaz, Fernando

    2015-01-01

    Memory capacity suffers an age-related decline, which is supposed to be due to a generalized slowing of processing speed and to a reduced availability of processing resources. Information encoding in memory has been demonstrated to be very sensitive to age-related changes, especially when carried out through self-initiated strategies or under high cognitive demands. However, most event-related potentials (ERP) research on age-related changes in working memory (WM) has used tasks that preclude distinction between age-related changes in encoding and retrieval processes. Here, we used ERP recording and a delayed match to sample (DMS) task with two levels of memory load to assess age-related changes in electrical brain activity in young and old adults during successful information encoding in WM. Age-related decline was reflected in lower accuracy rates and longer reaction times in the DMS task. Beside, only old adults presented lower accuracy rates under high than low memory load conditions. However, effects of memory load on brain activity were independent of age and may indicate an increased need of processing after stimulus classification as reflected in larger mean voltages in high than low load conditions between 550 and 1000 ms post-stimulus for young and old adults. Regarding age-related effects on brain activity, results also revealed smaller P2 and P300 amplitudes that may signal the existence of an age dependent reduction in the processing resources available for stimulus evaluation and categorization. Additionally, P2 and N2 latencies were longer in old than in young participants. Furthermore, longer N2 latencies were related to greater accuracy rates on the DMS task, especially in old adults. These results suggest that age-related slowing of processing speed may be specific for target stimulus analysis and evaluation processes. Thus, old adults seem to improve their performance the longer they take to evaluate the stimulus they encode in visual WM. PMID

  16. [Age-related changes of the brain].

    PubMed

    Paltsyn, A A; Komissarova, S V

    2015-01-01

    The first morphological signs of aging of the brain are found in the white matter already at a young age (20-40 years), and later (40-50 years) in a gray matter. After the 40-50 years appear and in subsequently are becoming more pronounced functional manifestations of morphological changes: the weakening of sensory-motor and cognitive abilities. While in principle this dynamic of age-related changes is inevitable, the rate of their development to a large extent determined by the genetic characteristics and lifestyle of the individual. According to modem concepts age-related changes in the number of nerve cells are different in different parts of the brain. However, these changes are not large and are not the main cause of senile decline brain. The main processes that contribute to the degradation of the brain develop as in the bodies of neurons and in neuropil. In the bodies of neurons--it is a damage (usually decrease) of the level of expression of many genes, and especially of the genes determining cell communication. In neuropil: reduction in the number of synapses and the strength of synaptic connections, reduction in the number of dendritic spines and axonal buttons, reduction in the number and thickness of the dendritic branches, demyelination of axons. As the result of these events, it becomes a violation of the rate of formation and rebuilding neuronal circuits. It is deplete associative ability, brain plasticity, and memory. PMID:27116888

  17. Age-Related Changes in Electrophysiological and Neuropsychological Indices of Working Memory, Attention Control, and Cognitive Flexibility

    PubMed Central

    Peltz, Carrie Brumback; Gratton, Gabriele; Fabiani, Monica

    2011-01-01

    Older adults exhibit great variability in their cognitive abilities, with some maintaining high levels of performance on executive control tasks and others showing significant deficits. Previous event-related potential (ERP) work has shown that some of these performance differences are correlated with persistence of the novelty/frontal P3 in older adults elicited by task-relevant events, presumably reflecting variability in the capacity to suppress orienting to unexpected but no longer novel events. In recent ERP work in young adults, we showed that the operation-span (OSPAN) task (a measure of attention control) is predictive of the ability of individuals to keep track of stimulus sequencing and to maintain running mental representations of task stimuli, as indexed by the parietally distributed P300 (or P3b). Both of these phenomena reflect aspects of frontal function (cognitive flexibility and attention control, respectively). To investigate these phenomena we sorted both younger and older adults into low- and high-working memory spans and low- and high-cognitive flexibility subgroups, and examined ERPs during an equal-probability choice reaction time task. For both age groups (a) participants with high OSPAN scores were better able to keep track of stimulus sequencing, as indicated by their smaller P3b to sequential changes; and (b) participants with lower cognitive flexibility had larger P3a than their high-scoring counterparts. However, these two phenomena did not interact suggesting that they manifest dissociable control mechanisms. Further, the fact that both effects are already visible in younger adults suggests that at least some of the brain mechanisms underlying individual differences in cognitive aging may already operate early in life. PMID:21887150

  18. Age-related changes in synaptic markers and monocyte subsets link the cognitive decline of APPSwe/PS1 mice

    PubMed Central

    Naert, Gaëlle; Rivest, Serge

    2012-01-01

    Alzheimer's disease (AD) is characterized by a progressive memory decline and numerous pathological abnormalities, including amyloid β (Aβ) accumulation in the brain and synaptic dysfunction. Here we wanted to study whether these brain changes were associated with alteration in the population of monocyte subsets since accumulating evidence supports the concept that the innate immune system plays a role in the etiology of this disease. We then determined the immune profile together with expression of genes encoding synaptic proteins and neurotrophins in APPSwe/PS1 mice and their age-matched wild-type (WT) littermates. We found that the progressive cognitive decline and the dramatic decrease in the expression of numerous synaptic markers and neurotrophins correlated with a major defect in the subset of circulating inflammatory monocytes. Indeed the number of CX3CR1lowLy6-ChighCCR2+Gr1+ monocytes remained essentially similar between 5 weeks and 6 months of age in APPSwe/PS1 mice, while these cells significantly increased in 6-month-old WT littermates. Of great interest is that the onset of cognitive decline was closely associated with the accumulation of soluble Aβ, disruption of synaptic activity, alteration in the BDNF system, and a defective production in the subset of CX3CR1lowLy6-ChighCCR2+Gr1+ monocytes. However, these memory impairments can be prevented or restored by boosting the monocytic production, using a short treatment of macrophage colony-stimulating factor (M-CSF). In conclusion, low CCR2+ monocyte production by the hematopoietic system may be a direct biomarker of the cognitive decline in a context of AD. PMID:23125823

  19. Veterans have less age-related cognitive decline.

    PubMed

    McLay, R N; Lyketsos, C G

    2000-08-01

    Military service involves exposure to a number of stresses, both psychological and physical. On the other hand, military personnel generally maintain excellent fitness, and veterans have increased access to education and health care. The overall effect on age-related cognitive decline, whether for good or ill, of having served in the armed forces has not been investigated previously. In this study, we examined a diverse population of 208 veterans and 1,216 civilians followed as part of the Epidemiologic Catchment Area Study in 1981, 1982, and 1993 to 1996. We examined change in Mini-Mental State Examination (MMSE) score after a median of 11.5 years. Veterans were found to have significantly less decrease in MMSE scores at follow-up even after sex, race, and education were taken into account. These results suggest an overall positive effect of military service on the rate of age-related cognitive decline. PMID:10957857

  20. Epigenetic modification of PKMζ rescues aging-related cognitive impairment.

    PubMed

    Chen, Chen; Meng, Shi-Qiu; Xue, Yan-Xue; Han, Ying; Sun, Cheng-Yu; Deng, Jia-Hui; Chen, Na; Bao, Yan-Ping; Zhang, Fei-Long; Cao, Lin-Lin; Zhu, Wei-Guo; Shi, Jie; Song, Wei-Hong; Lu, Lin

    2016-03-01

    Cognition is impacted by aging. However, the mechanisms that underlie aging-associated cognitive impairment are unclear. Here we showed that cognitive decline in aged rats was associated with changes in DNA methylation of protein kinase Mζ (PKMζ) in the prelimbic cortex (PrL). PKMζ is a crucial molecule involved in the maintenance of long-term memory. Using different behavioral models, we confirmed that aged rats exhibited cognitive impairment in memory retention test 24 h after training, and overexpression of PKMζ in the PrL rescued cognitive impairment in aged rats. After fear conditioning, the protein levels of PKMζ and the membrane expression of GluR2 increased in the PrL in young and adult rats but not in aged rats, and the levels of methylated PKMζ DNA in the PrL decreased in all age groups, whereas the levels of unmethylated PKMζ DNA increased only in young and adult rats. We also found that environmentally enriched housing reversed the hypermethylation of PKMζ and restored cognitive performance in aged rats. Inactivation of PKMζ prevented the potentiating effects of environmental enrichment on memory retention in aged rats. These results indicated that PKMζ might be a potential target for the treatment of aging-related cognitive impairment, suggesting a potential therapeutic avenue.

  1. Epigenetic modification of PKMζ rescues aging-related cognitive impairment

    PubMed Central

    Chen, Chen; Meng, Shi-Qiu; Xue, Yan-Xue; Han, Ying; Sun, Cheng-Yu; Deng, Jia-Hui; Chen, Na; Bao, Yan-Ping; Zhang, Fei-Long; Cao, Lin-Lin; Zhu, Wei-Guo; Shi, Jie; Song, Wei-Hong; Lu, Lin

    2016-01-01

    Cognition is impacted by aging. However, the mechanisms that underlie aging-associated cognitive impairment are unclear. Here we showed that cognitive decline in aged rats was associated with changes in DNA methylation of protein kinase Mζ (PKMζ) in the prelimbic cortex (PrL). PKMζ is a crucial molecule involved in the maintenance of long-term memory. Using different behavioral models, we confirmed that aged rats exhibited cognitive impairment in memory retention test 24 h after training, and overexpression of PKMζ in the PrL rescued cognitive impairment in aged rats. After fear conditioning, the protein levels of PKMζ and the membrane expression of GluR2 increased in the PrL in young and adult rats but not in aged rats, and the levels of methylated PKMζ DNA in the PrL decreased in all age groups, whereas the levels of unmethylated PKMζ DNA increased only in young and adult rats. We also found that environmentally enriched housing reversed the hypermethylation of PKMζ and restored cognitive performance in aged rats. Inactivation of PKMζ prevented the potentiating effects of environmental enrichment on memory retention in aged rats. These results indicated that PKMζ might be a potential target for the treatment of aging-related cognitive impairment, suggesting a potential therapeutic avenue. PMID:26926225

  2. Age Related Changes in Preventive Health Behavior.

    ERIC Educational Resources Information Center

    Leventhal, Elaine A.; And Others

    Health behavior may be influenced by age, beliefs, and symptomatology. To examine age-related health beliefs and behaviors with respect to six diseases (the common cold, colon-rectal cancer, lung cancer, heart attack, high blood pressure, and senility), 396 adults (196 males, 200 females) divided into three age groups completed a questionnaire…

  3. Age-Related Changes in the Misinformation Effect.

    ERIC Educational Resources Information Center

    Sutherland, Rachel; Hayne, Harlene

    2001-01-01

    Two experiments examined relation between age-related changes in retention and age-related changes in the misinformation effect. Found large age-related retention differences when participants were interviewed immediately and after 1 day, but after 6 weeks, differences were minimal. Exposure to misleading information increased commission errors.…

  4. Divergent Thinking and Age-Related Changes

    ERIC Educational Resources Information Center

    Palmiero, Massimiliano; Di Giacomo, Dina; Passafiume, Domenico

    2014-01-01

    Aging can affect cognition in different ways. The extent to which aging affects divergent thinking is unclear. In this study, younger and older adults were compared at the performance on the Torrance Test of Creative Thinking in visual and verbal form. Results showed that older adults can think divergently as younger participants, although they…

  5. Age-related changes to the production of linguistic prosody

    NASA Astrophysics Data System (ADS)

    Barnes, Daniel R.

    The production of speech prosody (the rhythm, pausing, and intonation associated with natural speech) is critical to effective communication. The current study investigated the impact of age-related changes to physiology and cognition in relation to the production of two types of linguistic prosody: lexical stress and the disambiguation of syntactically ambiguous utterances. Analyses of the acoustic correlates of stress: speech intensity (or sound-pressure level; SPL), fundamental frequency (F0), key word/phrase duration, and pause duration revealed that both young and older adults effectively use these acoustic features to signal linguistic prosody, although the relative weighting of cues differed by group. Differences in F0 were attributed to age-related physiological changes in the laryngeal subsystem, while group differences in duration measures were attributed to relative task complexity and the cognitive-linguistic load of these respective tasks. The current study provides normative acoustic data for older adults which informs interpretation of clinical findings as well as research pertaining to dysprosody as the result of disease processes.

  6. A Method for Investigating Age-related Differences in the Functional Connectivity of Cognitive Control Networks Associated with Dimensional Change Card Sort Performance

    PubMed Central

    DeBenedictis, Bianca; Morton, J. Bruce

    2014-01-01

    The ability to adjust behavior to sudden changes in the environment develops gradually in childhood and adolescence. For example, in the Dimensional Change Card Sort task, participants switch from sorting cards one way, such as shape, to sorting them a different way, such as color. Adjusting behavior in this way exacts a small performance cost, or switch cost, such that responses are typically slower and more error-prone on switch trials in which the sorting rule changes as compared to repeat trials in which the sorting rule remains the same. The ability to flexibly adjust behavior is often said to develop gradually, in part because behavioral costs such as switch costs typically decrease with increasing age. Why aspects of higher-order cognition, such as behavioral flexibility, develop so gradually remains an open question. One hypothesis is that these changes occur in association with functional changes in broad-scale cognitive control networks. On this view, complex mental operations, such as switching, involve rapid interactions between several distributed brain regions, including those that update and maintain task rules, re-orient attention, and select behaviors. With development, functional connections between these regions strengthen, leading to faster and more efficient switching operations. The current video describes a method of testing this hypothesis through the collection and multivariate analysis of fMRI data from participants of different ages. PMID:24837515

  7. Age-related changes in prefrontal norepinephrine transporter density: The basis for improved cognitive flexibility after low doses of atomoxetine in adolescent rats.

    PubMed

    Bradshaw, Sarah E; Agster, Kara L; Waterhouse, Barry D; McGaughy, Jill A

    2016-06-15

    Adolescence is a period of major behavioral and brain reorganization. As diagnoses and treatment of disorders like attention deficit hyperactivity disorder (ADHD) often occur during adolescence, it is important to understand how the prefrontal cortices change and how these changes may influence the response to drugs during development. The current study uses an adolescent rat model to study the effect of standard ADHD treatments, atomoxetine and methylphenidate on attentional set shifting and reversal learning. While both of these drugs act as norepinephrine reuptake inhibitors, higher doses of atomoxetine and all doses of methylphenidate also block dopamine transporters (DAT). Low doses of atomoxetine, were effective at remediating cognitive rigidity found in adolescents. In contrast, methylphenidate improved performance in rats unable to form an attentional set due to distractibility but was without effect in normal subjects. We also assessed the effects of GBR 12909, a selective DAT inhibitor, but found no effect of any dose on behavior. A second study in adolescent rats investigated changes in norepinephrine transporter (NET) and dopamine beta hydroxylase (DBH) density in five functionally distinct sub-regions of the prefrontal cortex: infralimbic, prelimbic, anterior cingulate, medial and lateral orbitofrontal cortices. These regions are implicated in impulsivity and distractibility. We found that NET, but not DBH, changed across adolescence in a regionally selective manner. The prelimbic cortex, which is critical to cognitive rigidity, and the lateral orbitofrontal cortex, critical to reversal learning and some forms of response inhibition, showed higher levels of NET at early than mid- to late adolescence. This article is part of a Special Issue entitled SI: Noradrenergic System. PMID:26774596

  8. Age-related changes in the rat hippocampus.

    PubMed

    Is, Merih; Comunoglu, Nil Ustundag; Comunoglu, Cem; Eren, Bulent; Ekici, Isin Dogan; Ozkan, Ferda

    2008-05-01

    The human brain is uniquely powerful in its cognitive abilities, yet the hippocampal and neocortical circuits that mediate these complex functions are highly vulnerable during aging. In this study, we analyzed age-related changes in the rat hippocampus by studying newborn (1 month), middle-aged (12 months), and older (24 months) male and female Sprague-Dawley rats. We evaluated neuronal dystrophy, neuron scattering, and granulovacuolar degeneration in the hippocampal area using light microscopy, according to age and gender. We detected significant neuronal dystrophy in the CA1, CA2, and CA3 areas in male rats, and in the CA1, CA3, and CA4 areas in female rats. Degenerative changes, indicated by neuron scattering, were observed in the CA1, CA2, and CA3 areas of male and the CA2 and CA4 areas of female rats. Changes in all areas of the hippocampus were observed with increasing age; these changes included neuronal dystrophy and neuron scattering and did not differ significantly between male and female rats.

  9. Age-Related Changes in 1/f Neural Electrophysiological Noise

    PubMed Central

    Kramer, Mark A.; Case, John; Lepage, Kyle Q.; Tempesta, Zechari R.; Knight, Robert T.; Gazzaley, Adam

    2015-01-01

    Aging is associated with performance decrements across multiple cognitive domains. The neural noise hypothesis, a dominant view of the basis of this decline, posits that aging is accompanied by an increase in spontaneous, noisy baseline neural activity. Here we analyze data from two different groups of human subjects: intracranial electrocorticography from 15 participants over a 38 year age range (15–53 years) and scalp EEG data from healthy younger (20–30 years) and older (60–70 years) adults to test the neural noise hypothesis from a 1/f noise perspective. Many natural phenomena, including electrophysiology, are characterized by 1/f noise. The defining characteristic of 1/f is that the power of the signal frequency content decreases rapidly as a function of the frequency (f) itself. The slope of this decay, the noise exponent (χ), is often <−1 for electrophysiological data and has been shown to approach white noise (defined as χ = 0) with increasing task difficulty. We observed, in both electrophysiological datasets, that aging is associated with a flatter (more noisy) 1/f power spectral density, even at rest, and that visual cortical 1/f noise statistically mediates age-related impairments in visual working memory. These results provide electrophysiological support for the neural noise hypothesis of aging. SIGNIFICANCE STATEMENT Understanding the neurobiological origins of age-related cognitive decline is of critical scientific, medical, and public health importance, especially considering the rapid aging of the world's population. We find, in two separate human studies, that 1/f electrophysiological noise increases with aging. In addition, we observe that this age-related 1/f noise statistically mediates age-related working memory decline. These results significantly add to this understanding and contextualize a long-standing problem in cognition by encapsulating age-related cognitive decline within a neurocomputational model of 1/f noise

  10. Age-Related Changes in 1/f Neural Electrophysiological Noise.

    PubMed

    Voytek, Bradley; Kramer, Mark A; Case, John; Lepage, Kyle Q; Tempesta, Zechari R; Knight, Robert T; Gazzaley, Adam

    2015-09-23

    Aging is associated with performance decrements across multiple cognitive domains. The neural noise hypothesis, a dominant view of the basis of this decline, posits that aging is accompanied by an increase in spontaneous, noisy baseline neural activity. Here we analyze data from two different groups of human subjects: intracranial electrocorticography from 15 participants over a 38 year age range (15-53 years) and scalp EEG data from healthy younger (20-30 years) and older (60-70 years) adults to test the neural noise hypothesis from a 1/f noise perspective. Many natural phenomena, including electrophysiology, are characterized by 1/f noise. The defining characteristic of 1/f is that the power of the signal frequency content decreases rapidly as a function of the frequency (f) itself. The slope of this decay, the noise exponent (χ), is often <-1 for electrophysiological data and has been shown to approach white noise (defined as χ = 0) with increasing task difficulty. We observed, in both electrophysiological datasets, that aging is associated with a flatter (more noisy) 1/f power spectral density, even at rest, and that visual cortical 1/f noise statistically mediates age-related impairments in visual working memory. These results provide electrophysiological support for the neural noise hypothesis of aging. Significance statement: Understanding the neurobiological origins of age-related cognitive decline is of critical scientific, medical, and public health importance, especially considering the rapid aging of the world's population. We find, in two separate human studies, that 1/f electrophysiological noise increases with aging. In addition, we observe that this age-related 1/f noise statistically mediates age-related working memory decline. These results significantly add to this understanding and contextualize a long-standing problem in cognition by encapsulating age-related cognitive decline within a neurocomputational model of 1/f noise-induced deficits in

  11. Glutamatergic regulation prevents hippocampal-dependent age-related cognitive decline through dendritic spine clustering

    PubMed Central

    Pereira, Ana C.; Lambert, Hilary K.; Grossman, Yael S.; Dumitriu, Dani; Waldman, Rachel; Jannetty, Sophia K.; Calakos, Katina; Janssen, William G.; McEwen, Bruce S.; Morrison, John H.

    2014-01-01

    The dementia of Alzheimer’s disease (AD) results primarily from degeneration of neurons that furnish glutamatergic corticocortical connections that subserve cognition. Although neuron death is minimal in the absence of AD, age-related cognitive decline does occur in animals as well as humans, and it decreases quality of life for elderly people. Age-related cognitive decline has been linked to synapse loss and/or alterations of synaptic proteins that impair function in regions such as the hippocampus and prefrontal cortex. These synaptic alterations are likely reversible, such that maintenance of synaptic health in the face of aging is a critically important therapeutic goal. Here, we show that riluzole can protect against some of the synaptic alterations in hippocampus that are linked to age-related memory loss in rats. Riluzole increases glutamate uptake through glial transporters and is thought to decrease glutamate spillover to extrasynaptic NMDA receptors while increasing synaptic glutamatergic activity. Treated aged rats were protected against age-related cognitive decline displayed in nontreated aged animals. Memory performance correlated with density of thin spines on apical dendrites in CA1, although not with mushroom spines. Furthermore, riluzole-treated rats had an increase in clustering of thin spines that correlated with memory performance and was specific to the apical, but not the basilar, dendrites of CA1. Clustering of synaptic inputs is thought to allow nonlinear summation of synaptic strength. These findings further elucidate neuroplastic changes in glutamatergic circuits with aging and advance therapeutic development to prevent and treat age-related cognitive decline. PMID:25512503

  12. Correlations among central serotonergic parameters and age-related emotional and cognitive changes assessed through the elevated T-maze and the Morris water maze.

    PubMed

    Oliveira, Luciana; Graeff, Frederico G; Pereira, Silvia R C; Oliveira-Silva, Ieda F; Franco, Glaura C; Ribeiro, Angela Maria

    2010-06-01

    Emotion and spatial cognitive aspects were assessed in adult and middle-aged rats using the elevated T-maze (ETM) and the Morris water maze (MWM) tasks. Both adult and middle-aged rats were able to acquire inhibitory avoidance behaviour, though the middle-aged subjects showed larger latencies along the trials, including the baseline, which was significantly longer than that showed by adult rats. Further, compared to adult rats, middle-aged rats had longer escape latency. In spite of the worse performance in the second session of the spatial cognitive task, the middle-aged rats were able to learn the task and remember the information along the whole probe trial test. Both thalamic serotonin (5-HT) concentration and amygdala serotonergic activity (5-HIAA/5-HT) are significantly correlated, respectively, to escape latency and behavioural extinction in the MWM only for middle-aged rats. A significant correlation between the 5-HIAA/5-HT ratio in the amygdala and behavioural extinction for middle-aged, but not for adult, rats was observed. This result suggests that serotonergic activity in the amygdala may regulate behavioural flexibility in aged animals. In addition, a significant negative correlation was found between hippocampal 5-HIAA/5-HT ratio and the path length at the second training session of the MWM task, although only for adult subjects. This was the only session where a significant difference between the performance of middle-aged and adult rats has occurred. Although the involvement of the hippocampus in learning and memory is well established, the present work shows, for the first time, a correlation between a serotonergic hippocampal parameter and performance of a spatial task, which is lost with ageing.

  13. Can psychosocial work conditions protect against age-related cognitive decline? Results from a systematic review.

    PubMed

    Nexø, Mette Andersen; Meng, Annette; Borg, Vilhelm

    2016-07-01

    According to the use it or lose it hypothesis, intellectually stimulating activities postpone age-related cognitive decline. A previous systematic review concluded that a high level of mental work demands and job control protected against cognitive decline. However, it did not distinguish between outcomes that were measured as cognitive function at one point in time or as cognitive decline. Our study aimed to systematically review which psychosocial working conditions were prospectively associated with high levels of cognitive function and/or changes in cognitive function over time. Articles were identified by a systematic literature search (MEDLINE, Web of Science (WOS), PsycNET, Occupational Safety and Health (OSH)). We included only studies with longitudinal designs examining the impact of psychosocial work conditions on outcomes defined as cognitive function or changes in cognitive function. Two independent reviewers compared title-abstract screenings, full-text screenings and quality assessment ratings. Eleven studies were included in the final synthesis and showed that high levels of mental work demands, occupational complexity or job control at one point in time were prospectively associated with higher levels of cognitive function in midlife or late life. However, the evidence to clarify whether these psychosocial factors also affected cognitive decline was insufficient, conflicting or weak. It remains speculative whether job control, job demands or occupational complexity can protect against cognitive decline. Future studies using methodological advancements can reveal whether workers gain more cognitive reserve in midlife and late life than the available evidence currently suggests. The public health implications of a previous review should thereby be redefined accordingly. PMID:27178844

  14. Can psychosocial work conditions protect against age-related cognitive decline? Results from a systematic review

    PubMed Central

    Nexø, Mette Andersen; Meng, Annette; Borg, Vilhelm

    2016-01-01

    According to the use it or lose it hypothesis, intellectually stimulating activities postpone age-related cognitive decline. A previous systematic review concluded that a high level of mental work demands and job control protected against cognitive decline. However, it did not distinguish between outcomes that were measured as cognitive function at one point in time or as cognitive decline. Our study aimed to systematically review which psychosocial working conditions were prospectively associated with high levels of cognitive function and/or changes in cognitive function over time. Articles were identified by a systematic literature search (MEDLINE, Web of Science (WOS), PsycNET, Occupational Safety and Health (OSH)). We included only studies with longitudinal designs examining the impact of psychosocial work conditions on outcomes defined as cognitive function or changes in cognitive function. Two independent reviewers compared title-abstract screenings, full-text screenings and quality assessment ratings. Eleven studies were included in the final synthesis and showed that high levels of mental work demands, occupational complexity or job control at one point in time were prospectively associated with higher levels of cognitive function in midlife or late life. However, the evidence to clarify whether these psychosocial factors also affected cognitive decline was insufficient, conflicting or weak. It remains speculative whether job control, job demands or occupational complexity can protect against cognitive decline. Future studies using methodological advancements can reveal whether workers gain more cognitive reserve in midlife and late life than the available evidence currently suggests. The public health implications of a previous review should thereby be redefined accordingly. PMID:27178844

  15. Prevention of Age-Related Cognitive Decline: Which Strategies, When, and for Whom?

    PubMed

    Shatenstein, Bryna; Barberger-Gateau, Pascale; Mecocci, Patrizia

    2015-01-01

    Brain aging is characterized by the progressive and gradual accumulation of detrimental changes in structure and function, which increase risk of age-related cognitive decline and dementia. This devastating chronic condition generates a huge social and economic burden and accounts for 11.2% of years of disability. The increase in lifespan has contributed to the increase in dementia prevalence; however, there is currently no curative treatment for most causes of dementias. This paper reviews evidence-based strategies to build, enhance, and preserve cognition over the lifespan by examining approaches that work best, proposing when in the life course they should be implemented, and in which population group(s). Recent work shows a tendency to decreased age-specific prevalence and incidence of cognitive problems and dementia among people born later in the first half of the 20th century, citing higher educational levels, improvements in lifestyle, and better handling of vascular risk factors. This implies that we can target modifiable environmental, lifestyle, and health risk factors to modify the trajectory of cognitive decline before the onset of irreversible dementia. Because building cognitive reserve and prevention of cognitive decline are of critical importance, interventions are needed at every stage of the life course to foster cognitive stimulation, and enable healthy eating habits and physical activity throughout the lifespan. Preventive interventions to decrease and delay cognitive decline and its consequences in old age will also require collaboration and action on the part of policy-makers at the political and social level.

  16. Anthropological contributions to the understanding of age-related cognitive impairment.

    PubMed

    Whitehouse, Peter J; Gaines, Atwood D; Lindstrom, Heather; Graham, Janice E

    2005-05-01

    Medical anthropology has not only helped us to understand the social, political, and ethical foundations of modern biomedicine, but also improved the identification and treatment of patients in various geographic, sociological, and medical contexts. In this article, we present an anthropological perspective on the understanding, diagnosis, and treatment of age-related cognitive impairment. The ubiquity of cognitive changes in the growing number of elderly people around the world, and the many diverse responses that human communities have taken to such challenges, require biocultural approaches. Anthropology can serve as an ally in accomplishing the goal of improving the quality of life of those with cognitive impairment by highlighting the role of sociocultural processes that influence the development, meaning, and experience of dementia. So too can it serve as a framework for criticism of biomedical research, theory, and practice. PMID:15847845

  17. The relevance of aging-related changes in brain function to rehabilitation in aging-related disease

    PubMed Central

    Crosson, Bruce; McGregor, Keith M.; Nocera, Joe R.; Drucker, Jonathan H.; Tran, Stella M.; Butler, Andrew J.

    2015-01-01

    The effects of aging on rehabilitation of aging-related diseases are rarely a design consideration in rehabilitation research. In this brief review we present strong coincidental evidence from these two fields suggesting that deficits in aging-related disease or injury are compounded by the interaction between aging-related brain changes and disease-related brain changes. Specifically, we hypothesize that some aphasia, motor, and neglect treatments using repetitive transcranial magnetic stimulation (rTMS) or transcranial direct current stimulation (tDCS) in stroke patients may address the aging side of this interaction. The importance of testing this hypothesis and addressing the larger aging by aging-related disease interaction is discussed. Underlying mechanisms in aging that most likely are relevant to rehabilitation of aging-related diseases also are covered. PMID:26074807

  18. From mind wandering to involuntary retrieval: Age-related differences in spontaneous cognitive processes.

    PubMed

    Maillet, David; Schacter, Daniel L

    2016-01-01

    The majority of studies that have investigated the effects of healthy aging on cognition have focused on age-related differences in voluntary and deliberately engaged cognitive processes. Yet many forms of cognition occur spontaneously, without any deliberate attempt at engaging them. In this article we review studies that have assessed age-related differences in four such types of spontaneous thought processes: mind-wandering, involuntary autobiographical memory, intrusive thoughts, and spontaneous prospective memory retrieval. These studies suggest that older adults exhibit a reduction in frequency of both mind-wandering and involuntary autobiographical memory, whereas findings regarding intrusive thoughts have been more mixed. Additionally, there is some preliminary evidence that spontaneous prospective memory retrieval may be relatively preserved in aging. We consider the roles of age-related differences in cognitive resources, motivation, current concerns and emotional regulation in accounting for these findings. We also consider age-related differences in the neural correlates of spontaneous cognitive processes.

  19. Closed-loop rehabilitation of age-related cognitive disorders.

    PubMed

    Mishra, Jyoti; Gazzaley, Adam

    2014-11-01

    Cognitive deficits are common in older adults, as a result of both the natural aging process and neurodegenerative disease. Although medical advancements have successfully prolonged the human lifespan, the challenge of remediating cognitive aging remains. The authors discuss the current state of cognitive therapeutic interventions and then present the need for development and validation of more powerful neurocognitive therapeutics. They propose that the next generation of interventions be implemented as closed-loop systems that target specific neural processing deficits, incorporate quantitative feedback to the individual and clinician, and are personalized to the individual's neurocognitive capacities using real-time performance-adaptive algorithms. This approach should be multimodal and seamlessly integrate other treatment approaches, including neurofeedback and transcranial electrical stimulation. This novel approach will involve the generation of software that engages the individual in an immersive and enjoyable game-based interface, integrated with advanced biosensing hardware, to maximally harness plasticity and assure adherence. Introducing such next-generation closed-loop neurocognitive therapeutics into the mainstream of our mental health care system will require the combined efforts of clinicians, neuroscientists, bioengineers, software game developers, and industry and policy makers working together to meet the challenges and opportunities of translational neuroscience in the 21st century. PMID:25520029

  20. The potential effects of meditation on age-related cognitive decline: a systematic review.

    PubMed

    Gard, Tim; Hölzel, Britta K; Lazar, Sara W

    2014-01-01

    With a rapidly aging society it becomes increasingly important to counter normal age-related decline in cognitive functioning. Growing evidence suggests that cognitive training programs may have the potential to counteract this decline. On the basis of a growing body of research that shows that meditation has positive effects on cognition in younger and middle-aged adults, meditation may be able to offset normal age-related cognitive decline or even enhance cognitive function in older adults. In this paper, we review studies investigating the effects of meditation on age-related cognitive decline. We searched the Web of Science (1900 to present), PsycINFO (1597 to present), MEDLINE (1950 to present), and CABI (1910 to present) to identify original studies investigating the effects of meditation on cognition and cognitive decline in the context of aging. Twelve studies were included in the review, six of which were randomized controlled trials. Studies involved a wide variety of meditation techniques and reported preliminary positive effects on attention, memory, executive function, processing speed, and general cognition. However, most studies had a high risk of bias and small sample sizes. Reported dropout rates were low and compliance rates high. We conclude that meditation interventions for older adults are feasible, and preliminary evidence suggests that meditation can offset age-related cognitive decline.

  1. The potential effects of meditation on age-related cognitive decline: a systematic review

    PubMed Central

    Gard, Tim; Hölzel, Britta K.; Lazar, Sara W.

    2014-01-01

    With a rapidly aging society it becomes increasingly important to counter normal age-related decline in cognitive functioning. Growing evidence suggests that cognitive training programs may have the potential to counteract this decline. On the basis of a growing body of research that shows that meditation has positive effects on cognition in younger and middle-aged adults, meditation may be able to offset normal age-related cognitive decline or even enhance cognitive function in older adults. In this paper, we review studies investigating the effects of meditation on age-related cognitive decline. We searched the Web of Science (1900 to present), PsycINFO (1597 to present), MEDLINE (1950 to present), and CABI (1910 to present) to identify original studies investigating the effects of meditation on cognition and cognitive decline in the context of aging. Twelve studies were included in the review, six of which were randomized controlled trials. Studies involved a wide variety of meditation techniques and reported preliminary positive effects on attention, memory, executive function, processing speed, and general cognition. However, most studies had a high risk of bias and small sample sizes. Reported dropout rates were low and compliance rates high. We conclude that meditation interventions for older adults are feasible, and preliminary evidence suggests that meditation can offset age-related cognitive decline. PMID:24571182

  2. Age-related changes in the meibomian gland.

    PubMed

    Nien, Chyong Jy; Paugh, Jerry R; Massei, Salina; Wahlert, Andrew J; Kao, Winston W; Jester, James V

    2009-12-01

    The purpose of this study was to characterize the age-related changes of the mouse meibomian gland. Eyelids from adult C57Bl/6 mice at 2, 6, 12 and 24 months of age were stained with specific antibodies against peroxisome proliferator activated receptor gamma (PPARgamma) to identify differentiating meibocytes, Oil Red O (ORO) to identify lipid, Ki67 nuclear antigen to identify cycling cells, B-lymphocyte-induced maturation protein-1 (Blimp1) to identify potential stem cells and CD45 to identify immune cells. Meibomian glands from younger mice (2 and 6 months) showed cytoplasmic and perinuclear staining with anti-PPARgamma antibodies with abundant ORO staining of small, intracellular lipid droplets. Meibomian glands from older mice (12 and 24 months) showed only nuclear PPARgamma localization with less ORO staining and significantly reduced acinar tissue (p < 0.04). Acini of older mice also showed significantly reduced (p < 0.004) numbers of Ki67 stained nuclei. While Blimp1 appeared to diffusely stain the superficial ductal epithelium, isolated cells were occasionally stained within the meibomian gland duct and acini of older mice that also stained with CD45 antibodies, suggesting the presence of infiltrating plasmacytoid cells. These findings suggest that there is altered PPARgamma receptor signaling in older mice that may underlie changes in cell cycle entry/proliferation, lipid synthesis and gland atrophy during aging. These results are consistent with the hypothesis that mouse meibomian glands undergo age-related changes similar to those identified in humans and may be used as a model for age-related meibomian gland dysfunction.

  3. Progressive Bidirectional Age-Related Changes in Default Mode Network Effective Connectivity across Six Decades

    PubMed Central

    Li, Karl; Laird, Angela R.; Price, Larry R.; McKay, D. Reese; Blangero, John; Glahn, David C.; Fox, Peter T.

    2016-01-01

    The default mode network (DMN) is a set of regions that is tonically engaged during the resting state and exhibits task-related deactivation that is readily reproducible across a wide range of paradigms and modalities. The DMN has been implicated in numerous disorders of cognition and, in particular, in disorders exhibiting age-related cognitive decline. Despite these observations, investigations of the DMN in normal aging are scant. Here, we used blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) acquired during rest to investigate age-related changes in functional connectivity of the DMN in 120 healthy normal volunteers comprising six, 20-subject, decade cohorts (from 20–29 to 70–79). Structural equation modeling (SEM) was used to assess age-related changes in inter-regional connectivity within the DMN. SEM was applied both using a previously published, meta-analytically derived, node-and-edge model, and using exploratory modeling searching for connections that optimized model fit improvement. Although the two models were highly similar (only 3 of 13 paths differed), the sample demonstrated significantly better fit with the exploratory model. For this reason, the exploratory model was used to assess age-related changes across the decade cohorts. Progressive, highly significant changes in path weights were found in 8 (of 13) paths: four rising, and four falling (most changes were significant by the third or fourth decade). In all cases, rising paths and falling paths projected in pairs onto the same nodes, suggesting compensatory increases associated with age-related decreases. This study demonstrates that age-related changes in DMN physiology (inter-regional connectivity) are bidirectional, progressive, of early onset and part of normal aging. PMID:27378909

  4. Progressive Bidirectional Age-Related Changes in Default Mode Network Effective Connectivity across Six Decades.

    PubMed

    Li, Karl; Laird, Angela R; Price, Larry R; McKay, D Reese; Blangero, John; Glahn, David C; Fox, Peter T

    2016-01-01

    The default mode network (DMN) is a set of regions that is tonically engaged during the resting state and exhibits task-related deactivation that is readily reproducible across a wide range of paradigms and modalities. The DMN has been implicated in numerous disorders of cognition and, in particular, in disorders exhibiting age-related cognitive decline. Despite these observations, investigations of the DMN in normal aging are scant. Here, we used blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) acquired during rest to investigate age-related changes in functional connectivity of the DMN in 120 healthy normal volunteers comprising six, 20-subject, decade cohorts (from 20-29 to 70-79). Structural equation modeling (SEM) was used to assess age-related changes in inter-regional connectivity within the DMN. SEM was applied both using a previously published, meta-analytically derived, node-and-edge model, and using exploratory modeling searching for connections that optimized model fit improvement. Although the two models were highly similar (only 3 of 13 paths differed), the sample demonstrated significantly better fit with the exploratory model. For this reason, the exploratory model was used to assess age-related changes across the decade cohorts. Progressive, highly significant changes in path weights were found in 8 (of 13) paths: four rising, and four falling (most changes were significant by the third or fourth decade). In all cases, rising paths and falling paths projected in pairs onto the same nodes, suggesting compensatory increases associated with age-related decreases. This study demonstrates that age-related changes in DMN physiology (inter-regional connectivity) are bidirectional, progressive, of early onset and part of normal aging. PMID:27378909

  5. Age-related changes in human vitreous structure.

    PubMed

    Sebag, J

    1987-01-01

    Changes in vitreous structure that occur with aging are important in the pathogenesis of vitreous liquefaction (synchisis senilis), vitreous detachment, and retinal disease. Vitreous morphology was studied in 59 human eyes post-mortem using dark-field horizontal slit illumination of the entire dissected vitreous. In many individuals younger than 30 years, the vitreous was homogeneous in structure. Middle-aged individuals had macroscopic fibers in the central vitreous, which coursed anteroposteriorly and inserted into the vitreous base and the vitreous cortex, posteriorly. During senescence, the vitreous volume was reduced, the vitreous body was collapsed (syneresis), and the fibers were thickened, tortuous, and surrounded by liquid vitreous. This sequence of age-related changes probably results from a progressive reorganization of the hyaluronic acid and collagen molecular networks. Characterization of the molecular events underlying these changes will elucidate the mechanisms of the phenomena of synchisis, syneresis, and detachment, and may provide methods with which to prevent or induce vitreous detachment prophylactically.

  6. Age-Related Neurochemical Changes in the Vestibular Nuclei.

    PubMed

    Smith, Paul F

    2016-01-01

    There is evidence that the normal aging process is associated with impaired vestibulo-ocular reflexes (VOR) and vestibulo-spinal reflexes, causing reduced visual acuity and postural instability. Nonetheless, the available evidence is not entirely consistent, especially with respect to the VOR. Some recent studies have reported that VOR gain can be intact even above 80 years of age. Similarly, although there is evidence for age-related hair cell loss and neuronal loss in Scarpa's ganglion and the vestibular nucleus complex (VNC), it is not entirely consistent. Whatever structural and functional changes occur in the VNC as a result of aging, either to cause vestibular impairment or to compensate for it, neurochemical changes must underlie them. However, the neurochemical changes that occur in the VNC with aging are poorly understood because the available literature is very limited. This review summarizes and critically evaluates the available evidence relating to the noradrenaline, serotonin, dopamine, glutamate, GABA, glycine, and nitric oxide neurotransmitter systems in the aging VNC. It is concluded that, at present, it is difficult, if not impossible, to relate the neurochemical changes observed to the function of specific VNC neurons and whether the observed changes are the cause of a functional deficit in the VNC or an effect of it. A better understanding of the neurochemical changes that occur during aging may be important for the development of potential drug treatments for age-related vestibular disorders. However, this will require the use of more sophisticated methodology such as in vivo microdialysis with single neuron recording and perhaps new technologies such as optogenetics. PMID:26973593

  7. Age-Related Neurochemical Changes in the Vestibular Nuclei

    PubMed Central

    Smith, Paul F.

    2016-01-01

    There is evidence that the normal aging process is associated with impaired vestibulo-ocular reflexes (VOR) and vestibulo-spinal reflexes, causing reduced visual acuity and postural instability. Nonetheless, the available evidence is not entirely consistent, especially with respect to the VOR. Some recent studies have reported that VOR gain can be intact even above 80 years of age. Similarly, although there is evidence for age-related hair cell loss and neuronal loss in Scarpa’s ganglion and the vestibular nucleus complex (VNC), it is not entirely consistent. Whatever structural and functional changes occur in the VNC as a result of aging, either to cause vestibular impairment or to compensate for it, neurochemical changes must underlie them. However, the neurochemical changes that occur in the VNC with aging are poorly understood because the available literature is very limited. This review summarizes and critically evaluates the available evidence relating to the noradrenaline, serotonin, dopamine, glutamate, GABA, glycine, and nitric oxide neurotransmitter systems in the aging VNC. It is concluded that, at present, it is difficult, if not impossible, to relate the neurochemical changes observed to the function of specific VNC neurons and whether the observed changes are the cause of a functional deficit in the VNC or an effect of it. A better understanding of the neurochemical changes that occur during aging may be important for the development of potential drug treatments for age-related vestibular disorders. However, this will require the use of more sophisticated methodology such as in vivo microdialysis with single neuron recording and perhaps new technologies such as optogenetics. PMID:26973593

  8. Epigenetic alterations in the suprachiasmatic nucleus and hippocampus contribute to age-related cognitive decline

    PubMed Central

    Deibel, Scott H.; Zelinski, Erin L.; Keeley, Robin J.; Kovalchuk, Olga; McDonald, Robert J.

    2015-01-01

    Circadian rhythm dysfunction and cognitive decline, specifically memory loss, frequently accompany natural aging. Circadian rhythms and memory are intertwined, as circadian rhythms influence memory formation and recall in young and old rodents. Although, the precise relationship between circadian rhythms and memory is still largely unknown, it is hypothesized that circadian rhythm disruption, which occurs during aging, contributes to age-associated cognitive decline, specifically memory loss. While there are a variety of mechanisms that could mediate this effect, changes in the epigenome that occur during aging has been proposed as a potential candidate. Interestingly, epigenetic mechanisms, such as DNA methylation and sirtuin1 (SIRT1) are necessary for both circadian rhythms and memory. During aging, similar alterations of epigenetic mechanisms occur in the suprachiasmatic nucleus (SCN) and hippocampus, which are necessary for circadian rhythm generation and memory, respectively. Recently, circadian rhythms have been linked to epigenetic function in the hippocampus, as some of these epigenetic mechanisms oscillate in the hippocampus and are disrupted by clock gene deletion. The current paper will review how circadian rhythms and memory change with age, and will suggest how epigenetic changes in these processes might contribute to age-related cognitive decline. PMID:26252151

  9. Epigenetic alterations in the suprachiasmatic nucleus and hippocampus contribute to age-related cognitive decline.

    PubMed

    Deibel, Scott H; Zelinski, Erin L; Keeley, Robin J; Kovalchuk, Olga; McDonald, Robert J

    2015-09-15

    Circadian rhythm dysfunction and cognitive decline, specifically memory loss, frequently accompany natural aging. Circadian rhythms and memory are intertwined, as circadian rhythms influence memory formation and recall in young and old rodents. Although, the precise relationship between circadian rhythms and memory is still largely unknown, it is hypothesized that circadian rhythm disruption, which occurs during aging, contributes to age-associated cognitive decline, specifically memory loss. While there are a variety of mechanisms that could mediate this effect, changes in the epigenome that occur during aging has been proposed as a potential candidate. Interestingly, epigenetic mechanisms, such as DNA methylation and sirtuin1 (SIRT1) are necessary for both circadian rhythms and memory. During aging, similar alterations of epigenetic mechanisms occur in the suprachiasmatic nucleus (SCN) and hippocampus, which are necessary for circadian rhythm generation and memory, respectively. Recently, circadian rhythms have been linked to epigenetic function in the hippocampus, as some of these epigenetic mechanisms oscillate in the hippocampus and are disrupted by clock gene deletion. The current paper will review how circadian rhythms and memory change with age, and will suggest how epigenetic changes in these processes might contribute to age-related cognitive decline. PMID:26252151

  10. Age-related cognitive decline during normal aging: the complex effect of education.

    PubMed

    Ardila, A; Ostrosky-Solis, F; Rosselli, M; Gómez, C

    2000-08-01

    The purpose of this study was to further analyze the effects of education on cognitive decline during normal aging. An 806-subject sample was taken from five different Mexican regions. Participants ranged in age from 16 to 85 years. Subjects were grouped into four educational levels: illiterate, 1-4, 5-9, and 10 or more years of education, and four age ranges: 16-30, 31-50, 51-65, and 66-85 years. A brief neuropsychological test battery (NEUROPSI), standardized and normalized in Spanish, was administered. The NEUROPSI test battery includes assessment of orientation, attention, memory, language, visuoperceptual abilities, motor skills, and executive functions. In general, test scores were strongly associated with level of educational, and differences among age groups were smaller than differences among education groups. However, there was an interaction between age and education such as that among illiterate individuals scores of participants 31-50 years old were higher than scores of participants 16-30 years old for over 50% of the tests. Different patterns of interaction among educational groups were distinguished. It was concluded that: (a) The course of life-span changes in cognition are affected by education. Among individuals with a low level of education, best neuropsychological test performance is observed at an older age than among higher-educated subjects; and (b) there is not a single relationship between age-related cognitive decline and education, but different patterns may be found, depending upon the specific cognitive domain. PMID:14590204

  11. Age-related differences in cognition across the adult lifespan in autism spectrum disorder.

    PubMed

    Lever, Anne G; Geurts, Hilde M

    2016-06-01

    It is largely unknown how age impacts cognition in autism spectrum disorder (ASD). We investigated whether age-related cognitive differences are similar, reduced or increased across the adult lifespan, examined cognitive strengths and weaknesses, and explored whether objective test performance is related to subjective cognitive challenges. Neuropsychological tests assessing visual and verbal memory, generativity, and theory of mind (ToM), and a self-report measure assessing cognitive failures were administered to 236 matched participants with and without ASD, aged 20-79 years (IQ > 80). Group comparisons revealed that individuals with ASD had higher scores on visual memory, lower scores on generativity and ToM, and similar performance on verbal memory. However, ToM impairments were no longer present in older (50+ years) adults with ASD. Across adulthood, individuals with ASD demonstrated similar age-related effects on verbal memory, generativity, and ToM, while age-related differences were reduced on visual memory. Although adults with ASD reported many cognitive failures, those were not associated with neuropsychological test performance. Hence, while some cognitive abilities (visual and verbal memory) and difficulties (generativity and semantic memory) persist across adulthood in ASD, others become less apparent in old age (ToM). Age-related differences characteristic of typical aging are reduced or parallel, but not increased in individuals with ASD, suggesting that ASD may partially protect against an age-related decrease in cognitive functioning. Despite these findings, adults with ASD experience many cognitive daily challenges, which highlights the need for adequate social support and the importance of further research into this topic, including longitudinal studies. Autism Res 2016, 9: 666-676. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.

  12. Age related changes in steroid receptors on cultured lung fibroblasts

    SciTech Connect

    Barile, F.A.; Bienkowski, R.S.

    1986-03-05

    The number of high affinity glucocorticoid receptors (Ro) on human fetal lung fibroblasts decreases as the cells age in vitro, and it has been suggested that these cell systems may be useful models of age-related changes in vivo. They examined the relation between change in Ro with in vitro aging and donor age. Confluent monolayers of lung fibroblasts at various population doubling levels (PDL), were incubated with (/sup 3/H)-dexamethasone ((/sup 3/H)Dex) either alone or with excess (.01 mM) Dex. Specific binding was calculated as the difference between radioactivity in cells incubated with and without unlabeled Dex; Scatchard plots were used to analyze the data. Ro, measured as fmol (/sup 3/H)Dex/10/sup 6/ cells, for two lines of human fetal cells (HFL-1 and MRC-5) decreased with increasing age in vitro. However, human newborn (CRL-1485) and adult (CCL-201) cells and fetal rabbit cells (FAB-290), showed increases in Ro with continuous passage. For each cell line, the affinity constant (K/sub d/) did not change significantly with passage. They conclude that the direction of changes in steroid receptor levels on cells aging in vitro is influenced by donor age and species. Caution should be used in applying results obtained from model systems to aging organisms.

  13. Age-related changes in deformability of human erythrocytes.

    PubMed

    Sutera, S P; Gardner, R A; Boylan, C W; Carroll, G L; Chang, K C; Marvel, J S; Kilo, C; Gonen, B; Williamson, J R

    1985-02-01

    The present study was designed to further the characterization of age-related changes in the deformability of human erythrocytes. The top (approximately young) and bottom (approximately old) 10% fractions of density-separated red cells from ten normal donors were subjected to graded levels of shear stress in a rheoscope. Measurements were made of steady-state elongation (cells tank treading in a state of dynamic equilibrium) and the time course of shape recovery following abrupt cessation of shear. In parallel with the rheologic experiments, several physical and chemical properties were assayed to determine correlates of mechanical properties. These included mean cell volume, mean corpuscular hemoglobin concentration, type A1 hemoglobin, glucosylation of membrane proteins, and membrane phospholipid and protein concentration. The microrheologic observations revealed that only about 90% of the old cells retained their capacity to tank tread. However, the tank-treading cells elongated less than their younger counterparts at corresponding levels of shear stress, thus demonstrating a reduced level of deformability. Further analysis of the data indicates that increases in membrane viscosity and elastic modulus along with a significant loss in excess surface area contribute to the limitation of the ability of the older cells to change shape.

  14. Age-related changes in skin topography and microcirculation.

    PubMed

    Li, Li; Mac-Mary, Sophie; Marsaut, David; Sainthillier, Jean Marie; Nouveau, Stéphanie; Gharbi, Tijani; de Lacharriere, Olivier; Humbert, Philippe

    2006-03-01

    Skin topography and microvasculature undergo characteristic changes with age. Although several non-invasive bioengineering methods are currently available to measure them quantitatively, few publications have referred to their relationship with age in different anatomical sites. This study was carried out to observe the age-related changes of the skin topography and skin microcirculation. The microrelief was assessed with special processing software from scanning by interference fringe profilometry of silicone replicas performed on two sites (volar forearm and back of hand) on 50 female volunteers (aged 20-74 years who consisted of ten probands in each decade). The superficial vascular network of both sites was assessed by videocapillaroscopy, and the subpapillary vascular plexus was studied with laser Doppler flowmetry. Skin color, which is affected by blood flow, was observed by colorimeter. The skin roughness and the mean height between peak and valley increased with age. There were statistically significant differences between the evaluated sites. This study also shows that the capillary loops in the dermal papillae decrease but the subpapillary plexus increase with age. The interference fringe profilometry associated with videocapillaroscopy may be useful and accurate to measure the efficacy of medical or cosmetic products to delay skin aging.

  15. Age-related decline in cognitive control: the role of fluid intelligence and processing speed

    PubMed Central

    2014-01-01

    Background Research on cognitive control suggests an age-related decline in proactive control abilities whereas reactive control seems to remain intact. However, the reason of the differential age effect on cognitive control efficiency is still unclear. This study investigated the potential influence of fluid intelligence and processing speed on the selective age-related decline in proactive control. Eighty young and 80 healthy older adults were included in this study. The participants were submitted to a working memory recognition paradigm, assessing proactive and reactive cognitive control by manipulating the interference level across items. Results Repeated measures ANOVAs and hierarchical linear regressions indicated that the ability to appropriately use cognitive control processes during aging seems to be at least partially affected by the amount of available cognitive resources (assessed by fluid intelligence and processing speed abilities). Conclusions This study highlights the potential role of cognitive resources on the selective age-related decline in proactive control, suggesting the importance of a more exhaustive approach considering the confounding variables during cognitive control assessment. PMID:24401034

  16. Heterogeneity in age-related white matter changes.

    PubMed

    Schmidt, Reinhold; Schmidt, Helena; Haybaeck, Johannes; Loitfelder, Marisa; Weis, Serge; Cavalieri, Margherita; Seiler, Stephan; Enzinger, Christian; Ropele, Stefan; Erkinjuntti, Timo; Pantoni, Leonardo; Scheltens, Philip; Fazekas, Franz; Jellinger, Kurt

    2011-08-01

    White matter changes occur endemically in routine magnetic resonance imaging (MRI) scans of elderly persons. MRI appearance and histopathological correlates of white matter changes are heterogeneous. Smooth periventricular hyperintensities, including caps around the ventricular horns, periventricular lining and halos are likely to be of non-vascular origin. They relate to a disruption of the ependymal lining with subependymal widening of the extracellular space and have to be differentiated from subcortical and deep white matter abnormalities. For the latter a distinction needs to be made between punctate, early confluent and confluent types. Although punctate white matter lesions often represent widened perivascular spaces without substantial ischemic tissue damage, early confluent and confluent lesions correspond to incomplete ischemic destruction. Punctate abnormalities on MRI show a low tendency for progression, while early confluent and confluent changes progress rapidly. The causative and modifying pathways involved in the occurrence of sporadic age-related white matter changes are still incompletely understood, but recent microarray and genome-wide association approaches increased the notion of pathways that might be considered as targets for therapeutic intervention. The majority of differentially regulated transcripts in white matter lesions encode genes associated with immune function, cell cycle, proteolysis, and ion transport. Genome-wide association studies identified six SNPs mapping to a locus on chromosome 17q25 to be related to white matter lesion load in the general population. We also report first and preliminary data that demonstrate apolipoprotein E (ApoE) immunoreactivity in white matter lesions and support epidemiological findings indicating that ApoE is another factor possibly related to white matter lesion occurrence. Further insights come from modern MRI techniques, such as diffusion tensor and magnetization transfer imaging, as they

  17. Defining the boundary: age-related changes in childhood amnesia.

    PubMed

    Tustin, Karen; Hayne, Harlene

    2010-09-01

    Childhood amnesia refers to the inability of adults to recall events that occurred during their infancy and early childhood. Although it is generally assumed that children and adolescents also experience childhood amnesia, with limited exceptions, most empirical research on the phenomenon has focused exclusively on adults. Here, we developed a new Timeline procedure to directly compare the early memories reported by children, adolescents, and adults. Overall, the proportion of memories reported before the age of 3 years was greater for the children and adolescents relative to the adults. In addition, the single earliest memory reported by children and adolescents was at a younger age than that reported by adults. In fact, the earliest memories reported by the children and adolescents, but not the adults, were significantly younger than the traditional 3 (1/2)-year-old boundary of childhood amnesia. Regardless of the age of the rememberer, participants' early memories had the same episodic characteristics. We conclude that the boundary and the density of childhood amnesia may increase over the course of human development and that age-related changes in basic memory mechanisms make an important contribution to our understanding of the source of childhood amnesia.

  18. Age-Related Changes in Demand–Withdraw Communication Behaviors

    PubMed Central

    Holley, Sarah R.; Haase, Claudia M.; Levenson, Robert W.

    2013-01-01

    Demand–withdraw communication is a set of conflict-related behaviors in which one partner blames or pressures while the other partner withdraws or avoids. The present study examined age-related changes in these behaviors longitudinally over the course of later life stages. One hundred twenty-seven middle-aged and older long-term married couples were observed at 3 time points across 13 years as they engaged in a conversation about an area of relationship conflict. Husbands’ and wives’ demand–withdraw behaviors (i.e., blame, pressure, withdrawal, avoidance) were objectively rated by trained coders at each time point. Data were analyzed using dyad-level latent growth curve models in a structural equation modeling framework. For both husbands and wives, the results showed a longitudinal pattern of increasing avoidance behavior over time and stability in all other demand and withdraw behaviors. This study supports the notion that there is an important developmental shift in the way that conflict is handled in later life. PMID:23913982

  19. The Age-Related Orientational Changes of Human Semicircular Canals

    PubMed Central

    Lyu, Hui-Ying; Chen, Ke-Guang; Yin, Dong-Ming; Hong, Juan; Yang, Lin; Zhang, Tian-Yu; Dai, Pei-Dong

    2016-01-01

    Objectives Some changes are found in the labyrinth anatomy during postnatal development. Although the spatial orientation of semicircular canals was thought to be stable after birth, we investigated the age-related orientational changes of human semicircular canals during development. Methods We retrospectively studied the computed tomography (CT) images of both ears of 76 subjects ranged from 1 to 70 years old. They were divided into 4 groups: group A (1–6 years), group B (7–12 years), group C (13–18 years), and group D (>18 years). The anatomical landmarks of the inner ear structures were determined from CT images. Their coordinates were imported into MATLAB software for calculating the semicircular canals orientation, angles between semicircular canal planes and the jugular bulb (JB) position. Differences between age groups were analyzed using multivariate statistics. Relationships between variables were analyzed using Pearson analysis. Results The angle between the anterior semicircular canal plane and the coronal plane, and the angle between the horizontal semicircular canal plane and the coronal plane were smaller in group D than those in group A (P<0.05). The JB position, especially the anteroposterior position of right JB, correlated to the semicircular canals orientation (P<0.05). However, no statistically significant differences in the angles between ipsilateral canal planes among different age groups were found. Conclusion The semicircular canals had tendencies to tilt anteriorly simultaneously as a whole with age. The JB position correlated to the spatial arrangement of semicircular canals, especially the right JB. Our calculation method helps detect developmental and pathological changes in vestibular anatomy. PMID:27090280

  20. A novel radial water tread maze tracks age-related cognitive decline in mice

    PubMed Central

    Pettan-Brewer, Christina; Touch, Dylan V.; Wiley, Jesse C.; Hopkins, Heather C.; Rabinovitch, Peter S.; Ladiges, Warren C.

    2013-01-01

    There is currently no treatment and cure for age-related dementia and cognitive impairment in humans. Mice suffer from age-related cognitive decline just as people do, but assessment is challenging because of cumbersome and at times stressful performance tasks. We developed a novel radial water tread (RWT) maze and tested male C57BL/6 (B6) and C57BL/6 x Balb/c F1 (CB6F1) mice at ages 4, 12, 20, and 28 months. B6 mice showed a consistent learning experience and memory retention that gradually decreased with age. CB6F1 mice showed a moderate learning experience in the 4 and 12 month groups, which was not evident in the 20 and 28 month groups. In conclusion, CB6F1 mice showed more severe age-related cognitive impairment compared to B6 mice and might be a suitable model for intervention studies. In addition, the RWT maze has a number of operational advantages compared to currently accepted tasks and can be used to assess age-related cognition impairment in B6 and CB6F1 mice as early as 12 months of age. PMID:24106580

  1. Myelin Breakdown Mediates Age-Related Slowing in Cognitive Processing Speed in Healthy Elderly Men

    ERIC Educational Resources Information Center

    Lu, Po H.; Lee, Grace J.; Tishler, Todd A.; Meghpara, Michael; Thompson, Paul M.; Bartzokis, George

    2013-01-01

    Background: To assess the hypothesis that in a sample of very healthy elderly men selected to minimize risk for Alzheimer's disease (AD) and cerebrovascular disease, myelin breakdown in late-myelinating regions mediates age-related slowing in cognitive processing speed (CPS). Materials and methods: The prefrontal lobe white matter and the genu of…

  2. Age-related changes in the Brazilian woman's smile.

    PubMed

    Correia, Luiza Nayara Almeida Lyra; Reis, Silvia Augusta Braga; Conti, Ana Claudia de Castro Ferreira; Capelozza Filho, Leopoldino; Almeida-Pedrin, Renata Rodrigues

    2016-01-01

    The aim of this research was to evaluate age-related changes in the smile of Brazilian women. The sample consisted of 249 Brazilian women who had not undergone previous orthodontic treatment or facial surgery. They were divided into four groups, according to age: G1 (20-29), G2 (30-39), G3 (40-49) and G4 (50 or older). Standardized front view photographs were taken while smiling and at rest. Measurements were evaluated by ANOVA and post-hoc Tukey. The Chi-square test was applied for qualitative variables. Upper lip thickness at rest and exposure of upper incisors on smiling decreased with age. Most individuals (60.9%) exhibited a medium smile. High smiles were more often seen in G1 (45%) and less frequently in G4 (18.8%), whereas the opposite occurred with the low smile, i.e., G4 (21.9%) and G1 (6.7%). Variations among the groups were observed in the transverse exposure of the teeth on smiling. In G1 and G3, there was a balance between tooth exposures, so that the teeth were exposed as far as the premolars and/or molars. Most of the women (56.3%) in G2 exposed their teeth as far as the first molars on smiling, whereas most of those (40.6%) in G4 exposed their teeth only as far as the first premolars on smiling. As age increased, there was decreased exposure of the upper incisors, decreased upper lip thickness and lower exposure of teeth vertically and transversely.

  3. Foreign language training as cognitive therapy for age-related cognitive decline: A hypothesis for future research

    PubMed Central

    Antoniou, Mark; Gunasekera, Geshri; Wong, Patrick C. M.

    2014-01-01

    Over the next fifty years, the number of older adults is set to reach record levels. Protecting older adults from the age-related effects of cognitive decline is one of the greatest challenges of the next few decades as it places increasing pressure on families, health systems, and economies on a global scale. The disease-state of age-related cognitive decline—Alzheimer's disease and other dementias—hijacks our consciousness and intellectual autonomy. However, there is evidence that cognitively stimulating activities protect against the adverse effects of cognitive decline. Similarly, bilingualism is also considered to be a safeguard. We propose that foreign language learning programs aimed at older populations are an optimal solution for building cognitive reserve because language learning engages an extensive brain network that is known to overlap with the regions negatively affected by the aging process. It is recommended that future research should test this potentially fruitful hypothesis. PMID:24051310

  4. Foreign language training as cognitive therapy for age-related cognitive decline: a hypothesis for future research.

    PubMed

    Antoniou, Mark; Gunasekera, Geshri M; Wong, Patrick C M

    2013-12-01

    Over the next fifty years, the number of older adults is set to reach record levels. Protecting older adults from the age-related effects of cognitive decline is one of the greatest challenges of the next few decades as it places increasing pressure on families, health systems, and economies on a global scale. The disease-state of age-related cognitive decline-Alzheimer's disease and other dementias-hijacks our consciousness and intellectual autonomy. However, there is evidence that cognitively stimulating activities protect against the adverse effects of cognitive decline. Similarly, bilingualism is also considered to be a safeguard. We propose that foreign language learning programs aimed at older populations are an optimal solution for building cognitive reserve because language learning engages an extensive brain network that is known to overlap with the regions negatively affected by the aging process. It is recommended that future research should test this potentially fruitful hypothesis. PMID:24051310

  5. Age-related changes in pial arterial structure and blood flow in mice.

    PubMed

    Kang, Hye-Min; Sohn, Inkyung; Jung, Junyang; Jeong, Joo-Won; Park, Chan

    2016-01-01

    Age-related cerebral blood flow decreases are thought to deteriorate cognition and cause senescence, although the related mechanism is unclear. To investigate the relationships between aging and changes in cerebral blood flow and vasculature, we obtained fluorescence images of young (2-month-old) and old (12-month-old) mice using indocyanine green (ICG). First, we found that the blood flow in old mice's brains is lower than that in young mice and that old mice had more curved pial arteries and fewer pial artery junctions than young mice. Second, using Western blotting, we determined that the ratio of collagen to elastin (related to cerebral vascular wall distensibility) increased with age. Finally, we found that the peak ICG intensity and blood flow index decreased, whereas the mean transit time increased, with age in the middle cerebral artery and superior sagittal sinus. Age-related changes in pial arterial structure and composition, concurrent with the observed changes in the blood flow parameters, suggest that age-related changes in the cerebral vasculature structure and distensibility may induce altered brain blood flow.

  6. Age-related changes in ultra-triathlon performances

    PubMed Central

    2012-01-01

    Background The age-related decline in performance has been investigated in swimmers, runners and triathletes. No study has investigated the age-related performance decline in ultra-triathletes. The purpose of this study was to analyse the age-related declines in swimming, cycling, running and overall race time for both Triple Iron ultra-triathlon (11.4-km swimming, 540-km cycling and 126.6-km running) and Deca Iron ultra-triathlon (38-km swimming, 1,800-km cycling and 420-km running). Methods The age and performances of 423 male Triple Iron ultra-triathletes and 119 male Deca Iron ultra-triathletes were analysed from 1992 to 2010 using regression analyses and ANOVA. Results The mean age of the finishers was significantly higher for Deca Iron ultra-triathletes (41.3 ± 3.1 years) compared to a Triple Iron ultra-triathletes (38.5 ± 3.3 years) (P < 0.05). For both ultra-distances, the fastest overall race times were achieved between the ages of 25 and 44 years. Deca Iron ultra-triathletes achieved the same level of performance in swimming and cycling between 25 and 54 years of age. Conclusions The magnitudes of age-related declines in performance in the three disciplines of ultra-triathlon differ slightly between Triple and Deca Iron ultra-triathlon. Although the ages of Triple Iron ultra-triathletes were on average younger compared to Deca Iron ultra-triathletes, the fastest race times were achieved between 25 and 44 years for both distances. Further studies should investigate the motivation and training of ultra-triathletes to gain better insights in ultra-triathlon performance. PMID:23849327

  7. Effects of a computer-based cognitive exercise program on age-related cognitive decline.

    PubMed

    Bozoki, Andrea; Radovanovic, Mirjana; Winn, Brian; Heeter, Carrie; Anthony, James C

    2013-01-01

    We developed a 'senior friendly' suite of online 'games for learning' with interactive calibration for increasing difficulty, and evaluated the feasibility of a randomized clinical trial to test the hypothesis that seniors aged 60-80 can improve key aspects of cognitive ability with the aid of such games. Sixty community-dwelling senior volunteers were randomized to either an online game suite designed to train multiple cognitive abilities, or to a control arm with online activities that simulated the look and feel of the games but with low level interactivity and no calibration of difficulty. Study assessment included measures of recruitment, retention and play-time. Cognitive change was measured with a computerized assessment battery administered just before and within two weeks after completion of the six-week intervention. Impediments to feasibility included: limited access to in-home high-speed internet, large variations in the amount of time devoted to game play, and a reluctance to pursue more challenging levels. Overall analysis was negative for assessed performance (transference effects) even though subjects improved on the games themselves. Post hoc analyses suggest that some types of games may have more value than others, but these effects would need to be replicated in a study designed for that purpose. We conclude that a six-week, moderate-intensity computer game-based cognitive intervention can be implemented with high-functioning seniors, but the effect size is relatively small. Our findings are consistent with Owen et al. (2010), but there are open questions about whether more structured, longer duration or more intensive 'games for learning' interventions might yield more substantial cognitive improvement in seniors.

  8. Cognitive Reserve Modifies Age-Related Alterations in CSF Biomarkers of Alzheimer's Disease

    PubMed Central

    Almeida, Rodrigo P.; Schultz, Stephanie A.; Austin, Benjamin P.; Boots, Elizabeth A.; Dowling, N. Maritza; Gleason, Carey E.; Bendlin, Barbara B.; Sager, Mark; Hermann, Bruce P.; Zetterberg, Henrik; Carlsson, Cindy; Johnson, Sterling; Asthana, Sanjay; Okonkwo, Ozioma C.

    2015-01-01

    Importance Although advancing age is the strongest risk factor for the development of symptomatic Alzheimer's disease (AD), recent studies have shown that there are individual differences in susceptibility to age-related alterations in the biomarkers of AD pathophysiology. Objective In this study, we investigated whether cognitive reserve modifies the adverse influence of age on key cerebrospinal fluid (CSF) biomarkers of AD. Design, Setting, and Participants Cross-sectional cohort of 268 individuals (211 cognitively normal and 57 cognitively impaired) from the Wisconsin Registry for Alzheimer's Prevention and the Wisconsin Alzheimer's Disease Research Center participated in this study. They underwent lumbar puncture for collection of CSF samples, from which amyloid-β 42 (Aβ42), total tau (t-tau), and phosphorylated tau (p-tau) were immunoassayed. Additionally, we computed t-tau/Aβ42 and p-tau/Aβ42 ratios. Cognitive reserve was indexed by years of education, with ≥16 years taken to confer high reserve. Covariate-adjusted regression analyses were used to test whether the effect of age on CSF biomarkers was modified by cognitive reserve. Main outcome measures CSF levels of Aβ42, t-tau, p-tau, t-tau/Aβ42, and p-tau/Aβ42. Results There were significant age*cognitive reserve interactions for CSF t-tau (p=.019), p-tau (p=.009), t-tau/Aβ42 (p=.021), and p-tau/Aβ42 (p=.004). Specifically, with advancing age, individuals with high cognitive reserve exhibited attenuated adverse alterations in these CSF biomarkers compared with individuals with low cognitive reserve. This attenuation of age effects by cognitive reserve tended to be more pronounced in the cognitively-impaired group compared with the cognitively-normal group. Lastly, there was modest evidence of a dose response relationship such that the effect of age on the biomarkers was progressively attenuated given additional years of schooling. Conclusions and Relevance In a sample comprised of both cognitively

  9. Superficial white matter as a novel substrate of age-related cognitive decline.

    PubMed

    Nazeri, Arash; Chakravarty, M Mallar; Rajji, Tarek K; Felsky, Daniel; Rotenberg, David J; Mason, Mikko; Xu, Li N; Lobaugh, Nancy J; Mulsant, Benoit H; Voineskos, Aristotle N

    2015-06-01

    Studies of diffusion tensor imaging have focused mainly on the role of deep white matter tract microstructural abnormalities associated with aging and age-related cognitive decline. However, the potential role of superficial white matter (SWM) in aging and, by extension, cognitive-aging, is less clear. Healthy individuals (n = 141; F/M: 66/75 years) across the adult lifespan (18-86 years) underwent diffusion tensor imaging and a battery of cognitive testing. SWM was assessed via a combination of probabilistic tractography and tract-based spatial statistics (TBSS). A widespread inverse relationship of fractional anisotropy (FA) values in SWM with age was observed. SWM-FA adjacent to the precentral gyri was associated with fine-motor-speed, whereas performance in visuomotor-attention/processing speed correlated with SWM-FA in all 4 lobes of the left-hemisphere and in right parieto-occipital SWM-FA (family-wise error corrected p < 0.05). Independent of deep white matter-FA, right frontal and right occipital SWM-FA-mediated age effects on motor-speed and visuomotor-attention/processing speed, respectively. Altogether, our results indicate that SWM-FA contributes uniquely to age-related cognitive performance, and should be considered as a novel biomarker of cognitive-aging. PMID:25834938

  10. Differential Trajectories of Age-Related Changes in Components of Executive and Memory Processes

    PubMed Central

    Goh, Joshua O.; An, Yang; Resnick, Susan M.

    2012-01-01

    Several studies have demonstrated age-related declines in general executive function and memory. In this study, we examined cross-sectional and longitudinal age effects in more specific cognitive processes that constitute executive function and memory. We postulated that, whereas some components of executive and memory functions would show age differences and longitudinal declines, other specific abilities would be maintained or even improve with repeated testing. In a sample of individuals ≥55 years old from the Baltimore Longitudinal Study of Aging, we found longitudinal declines in inhibition, manipulation, semantic retrieval, phonological retrieval, switching, and long-term memory over a maximum of 14 years follow-up. In contrast, abstraction, capacity, chunking, discrimination, and short-term memory were maintained or even improved longitudinally, probably due in part to repeated testing. Moreover, whereas several different abilities were correlated across participants’ cross-sectional performance, longitudinal changes in performance showed more heterogeneous trajectories. Finally, compared with cross-sectional performance, longitudinal trajectories showed better distinction between participants with and those without later cognitive impairment. These results show that longitudinal cognitive aging of executive and memory functions is not a uniform process but a heterogeneous one and suggest that certain executive and memory functions remain stable despite age-related declines in other component processes. PMID:22201331

  11. Age-related neural changes in autobiographical remembering and imagining.

    PubMed

    Addis, Donna Rose; Roberts, Reece P; Schacter, Daniel L

    2011-11-01

    Numerous neuroimaging studies have revealed that in young adults, remembering the past and imagining the future engage a common core network. Although it has been observed that older adults engage a similar network during these tasks, it is unclear whether or not they activate this network in a similar manner to young adults. Young and older participants completed two autobiographical tasks (imagining future events and recalling past events) in addition to a semantic-visuospatial control task. Spatiotemporal Partial Least Squares analyses examined whole brain patterns of activity across both the construction and elaboration of autobiographical events. These analyses revealed that that both age groups activated a similar network during the autobiographical tasks. However, some key age-related differences in the activation of this network emerged. During the construction of autobiographical events, older adults showed less activation relative to younger adults, in regions supporting episodic detail such as the medial temporal lobes and the precuneus. Later in the trial, older adults showed differential recruitment of medial and lateral temporal regions supporting the elaboration of autobiographical events, and possibly reflecting an increased role of conceptual information when older adults describe their pasts and their futures.

  12. Oxidative modification of proteins: age-related changes.

    PubMed

    Chakravarti, Bulbul; Chakravarti, Deb N

    2007-01-01

    Aging is a complex biological phenomenon which involves progressive loss of different physiological functions of various tissues of living organisms. It is the inevitable fate of life and is a major risk factor for death and different pathological disorders. Based on a wide variety of studies performed in humans as well as in various animal models and microbial systems, reactive oxygen species (ROS) are believed to play a key role in the aging process. The production of ROS is influenced by cellular metabolic activities as well as environmental factors. ROS can react with all major biological macromolecules such as carbohydrates, nucleic acids, lipids, and proteins. Since, in general, proteins are the key molecules that play the ultimate role in various structural and functional aspects of living organisms, this review will focus on the age-related oxidative modifications of proteins as well as on mechanism for removal or repair of the oxidized proteins. The topics covered include protein oxidation as a marker of oxidative stress, experimental evidence indicating the role of ROS in protein oxidation, protein carbonyl content, enzymatic degradation of oxidized proteins, and effects of caloric restriction on protein oxidation in the context of aging. Finally, we will discuss different strategies which have been or can be undertaken to slow down the oxidative damage of proteins and the aging process.

  13. Computer Simulations of Loss of Organization of Neurons as a Model for Age-related Cognitive Decline

    NASA Astrophysics Data System (ADS)

    Cruz, Luis; Fengometidis, Elene; Jones, Frank; Jampani, Srinivas

    2011-03-01

    In normal aging, brains suffer from progressive cognitive decline not linked with loss of neurons common in neurodegenerative disorders such as Alzheimer's disease. However, in some brain areas neurons have lost positional organization specifically within microcolumns: arrays of interconnected neurons which may constitute fundamental computational units in the brain. This age-related loss of organization, likely a result of micron-sized random displacements in neuronal positions, is hypothesized to be a by-product of the loss of support from the surrounding medium, including dendrites. Using a dynamical model applied to virtual 3D representation of neuronal arrangements, that previously showed loss of organization in brains of cognitively tested rhesus monkeys, the relationship between these displacements and changes to the surrounding dendrite network are presented. The consequences of these displacements on the structure of the dendritic network, with possible disruptions in signal synchrony important to cognitive function, are discussed. NIH R01AG021133.

  14. Age-Related Cognitive Deficits In Rhesus Monkeys Mirror Human Deficits on an Automated Test Battery

    PubMed Central

    Nagahara, Alan H.; Bernot, Tim; Tuszynski, Mark H.

    2010-01-01

    Aged non-human primates are a valuable model for gaining insight into mechanisms underlying neural decline with aging and during the course of neurodegenerative disorders. Behavioral studies are a valuable component of aged primate models, but are difficult to perform, time consuming, and often of uncertain relevance to human cognitive measures. We now report findings from an automated cognitive test battery in aged primates using equipment that is identical, and tasks that are similar, to those employed in human aging and Alzheimer’s disease studies. Young (7.1 ± 0.8 years) and aged (23.0 ± 0.5 years) rhesus monkeys underwent testing on a modified version of the Cambridge Automated Neuropsychological Test Battery (CANTAB), examining cognitive performance on separate tasks that sample features of visuospatial learning, spatial working memory, discrimination learning, and skilled motor performance. We find selective cognitive impairments among aged subjects in visuospatial learning and spatial working memory, but not in delayed recall of previously learned discriminations. Aged monkeys also exhibit slower speed in skilled motor function. Thus, aged monkeys behaviorally characterized on a battery of automated tests reveal patterns of age-related cognitive impairment that mirror in quality and severity those of aged humans, and differ fundamentally from more severe patterns of deficits observed in Alzheimer’s Disease. PMID:18760505

  15. Who Moved My Cheese? Adjusting to Age-Related Changes

    ERIC Educational Resources Information Center

    Langer, Nieli

    2012-01-01

    The popular book, Who Moved My Cheese? (Johnson, 1998) is a metaphor for change. This parable-like story has particular resonance with older adults who face many potential life-altering changes. The four characters in the book are looking for their cheese in a maze. Cheese represents whatever makes people happy. How each character adjusts to the…

  16. High cognitive reserve is associated with a reduced age-related deficit in spatial conflict resolution

    PubMed Central

    Puccioni, Olga; Vallesi, Antonino

    2012-01-01

    Several studies support the existence of a specific age-related difficulty in suppressing potentially distracting information. The aim of the present study is to investigate whether spatial conflict resolution is selectively affected by aging. The way aging affects individuals could be modulated by many factors determined by the socieconomic status: we investigated whether factors such as cognitive reserve (CR) and years of education may play a compensatory role against age-related deficits in the spatial domain. A spatial Stroop task with no feature repetitions was administered to a sample of 17 non-demented older adults (69–79 years-old) and 18 younger controls (18–34 years-old) matched for gender and years of education. The two age groups were also administered with measures of intelligence and CR. The overall spatial Stroop effect did not differ according to age, neither for speed nor for accuracy. The two age groups equally showed sequential effects for congruent trials: reduced response times (RTs) if another congruent trial preceded them, and accuracy at ceiling. For incongruent trials, older adults, but not younger controls, were influenced by congruency of trialn−1, since RTs increased with preceding congruent trials. Interestingly, such an age-related modulation negatively correlated with CR. These findings suggest that spatial conflict resolution in aging is predominantly affected by general slowing, rather than by a more specific deficit. However, a high level of CR seems to play a compensatory role for both factors. PMID:23248595

  17. Age-related differences in gap detection: Effects of task difficulty and cognitive ability

    PubMed Central

    Harris, Kelly C.; Eckert, Mark A.; Ahlstrom, Jayne B.; Dubno, Judy R.

    2009-01-01

    Differences in gap detection for younger and older adults have been shown to vary with the complexity of the task or stimuli, but the factors that contribute to these differences remain unknown. To address this question, we examined the extent to which age-related differences in processing speed and workload predicted age-related differences in gap detection. Gap detection thresholds were measured for 10 younger and 11 older adults in two conditions that varied in task complexity but used identical stimuli: (1) gap location fixed at the beginning, middle, or end of a noise burst and (2) gap location varied randomly from trial to trial from the beginning, middle, or end of the noise. We hypothesized that gap location uncertainty would place increased demands on cognitive and attentional resources and result in significantly higher gap detection thresholds for older but not younger adults. Overall, gap detection thresholds were lower for the middle location as compared to beginning and end locations and were lower for the fixed than the random condition. In general, larger age-related differences in gap detection were observed for more challenging conditions. That is, gap detection thresholds for older adults were significantly larger for the random condition than for the fixed condition when the gap was at the beginning and end locations but not the middle. In contrast, gap detection thresholds for younger adults were not significantly different for the random and fixed condition at any location. Subjective ratings of workload indicated that older adults found the gap-detection task more mentally demanding than younger adults. Consistent with these findings, results of the Purdue Pegboard and Connections tests revealed age-related slowing of processing speed. Moreover, age group differences in workload and processing speed predicted gap detection in younger and older adults when gap location varied from trial to trial; these associations were not observed when gap

  18. Age-Related Psychophysical Changes and Low Vision

    PubMed Central

    Dagnelie, Gislin

    2013-01-01

    When considering the burden of visual impairment on aging individuals and society at large, it is important to bear in mind that vision changes are a natural aspect of aging. In this article, we consider vision changes that are part of normal aging, the prevalence of abnormal vision changes caused by disorders of the visual system, and the anticipated incidence and impact of visual impairment as the US population ages. We then discuss the services available to reduce the impact of vision loss, and the extent to which those services can and should be improved, not only to be better prepared for the anticipated increase in low vision over the coming decades, but also to increase the awareness of interactions between visual impairment and comorbidities that are common among the elderly. Finally, we consider how to promote improved quality, availability, and acceptance of low vision care to lessen the impact of visual impairment on individuals, and its burden on society. PMID:24335074

  19. Age-related changes in postural control to the demands of a precision task.

    PubMed

    Yeh, Ting-Ting; Cinelli, Michael E; Lyons, James L; Lee, Timothy D

    2015-12-01

    Optimal sensorimotor integration is needed to maintain the precision of a visuomotor postural task. Furthermore, cognitive resources have been suggested to be involved in maintaining balance, especially in older adults. This study investigated how older and younger adults differed in employing sensorimotor strategies in a dual-task situation. Older (age 65-84 years) and younger adults (age 19-30 years) performed a visually-based, postural tracking task in different body orientations (from 0° to 45°), which necessitated slightly different task goals. On some trials, participants performed a concurrent silent arithmetic task with the visuomotor tracking task. The results demonstrated that sensorimotor control declined with age. Older adults showed greater medial-lateral center of pressure variability compared to younger adults in the precision task. Younger adults displayed a trend to decrease anterior-posterior variability, but older adults exhibited an opposite trend when the body orientation changed from 0° to 45°. The addition of a dual-task situation decreased overall postural variability in both age groups. Age-related changes in postural control may degrade the flexible coordination of the sensory feedback and motor execution. This study suggested that medial-lateral stability may be more sensitive to this age-related decline and may be closely associated with postural instability and falls.

  20. Age-related changes in genomic stability of horses.

    PubMed

    Wnuk, Maciej; Bugno-Poniewierska, Monika; Lewinska, Anna; Oklejewicz, Bernadetta; Zabek, Tomasz; Bartosz, Grzegorz; Słota, Ewa

    2011-05-01

    Recently, the old horse has been proposed as a model to study telomere-dependent senescence, immunosenescence and inflamm-aging. In the present paper, we used 80 Hucul and Anglo-Arabian horses divided into 3 age groups (juvenile, adult, old) to evaluate age-dependent changes at the genomic and DNA level and in cell proliferative potential. The level of positive TUNEL cells (both apoptotic and with DNA fragmentation), oxidative DNA damage (8-oxoG immunostaining), sister chromatid exchange and bleomycin-induced chromatid breaks were significantly increased in the combined old group compared to the combined adult group. We observed a negative correlation between micronuclei formation and age, which may be associated with damaged cells undergoing apoptosis, rather than expressing micronuclei. We were unable to show any significant changes in the nuclear division index value, which reflects the proliferative status of the viable cell fraction during aging. Here, we show that breed-independent and age-associated changes in genomic stability may contribute, at least in part, to the aging process in the horse. PMID:21557962

  1. [Age-related changes in swallowing. Physiology and pathophysiology].

    PubMed

    Muhle, P; Wirth, R; Glahn, J; Dziewas, R

    2015-04-01

    The term presbyphagia refers to all changes of swallowing physiology that are manifested with increasing age. Alterations in the pattern of deglutition that are part of healthy aging are called primary presbyphagia. Primary presbyphagia is not an illness in itself but contributes to a more pervasive naturally diminished functional reserve, making older adults more susceptible to dysphagia. If disorders in swallowing occur in the elderly as a comorbidity of a specific disease, for example stroke or neurodegenerative disorders, this is called secondary presbyphagia. Increasing age has an impact on each stage of deglutition. In the oral preparatory phase a diminished input for smell and taste as well as a usually multifactorial cause of dry mouth are the most important influencing factors. Sarcopenia, the degenerative loss of skeletal muscle mass, strength and quality associated with aging, interferes in particular with the oropharyngeal phase. A decreased sensory feedback from the oropharyngeal mucosa leads to a delayed triggering of the swallowing reflex. Finally, a reduction in connective tissue elasticity and changes of the axial skeleton lead to various modifications of the swallowing pattern with advanced age.

  2. Dosimetric implications of age related glandular changes in screening mammography

    NASA Astrophysics Data System (ADS)

    Beckett, J. R.; Kotre, C. J.

    2000-03-01

    The UK National Health Service Breast Screening Programme is currently organized to routinely screen women between the ages of 50 and 64, with screening for older women available on request. The lower end of this age range closely matches the median age for the menopause (51 years), during which significant changes in the composition of the breast are known to occur. In order to quantify the dosimetric effect of these changes, radiographic factors and compressed breast thickness data for a cohort of 1258 women aged between 35 and 79 undergoing breast screening mammography have been used to derive estimates of breast glandularity and mean glandular dose (MGD), and examine their variation with age. The variation of mean radiographic exposure factors with age is also investigated. The presence of a significant number of age trial women within the cohort allowed an extended age range to be studied. Estimates of MGD including corrections for breast glandularity based on compressed breast thickness only, compressed breast thickness and age and for each individual woman are compared with the MGD based on the conventional assumption of a 50:50 adipose/glandular composition. It has been found that the use of the conventional 50:50 assumption leads to overestimates of MGD of up to 13% over the age range considered. By using compressed breast thickness to estimate breast glandularity, this error range can be reduced to 8%, whilst age and compressed breast thickness based glandularity estimates result in an error range of 1%.

  3. Awareness of Age-Related Change: Examination of a (Mostly) Unexplored Concept

    PubMed Central

    Wahl, Hans-Werner

    2010-01-01

    This theoretical article discusses the emerging concept of awareness of age-related change (AARC). We propose that a focus on AARC extends the research traditions on subjective age experiences and age identity and that examination of this concept can serve a stimulating role in social gerontology. After defining and contrasting AARC against similar concepts, several reasons for the relevance of this mostly unexplored construct are provided. The sample domains of health and physical functioning, cognitive functioning, and interpersonal relations are used to illustrate the relevance of AARC. Based on this review, we then provide a heuristic framework that describes antecedents, processes, and outcomes related to AARC. Overall, we argue that research on AARC should become an integral part of social gerontological research. PMID:20008026

  4. [Presbiphonia. Age-related changes in the acoustic voice characteristics].

    PubMed

    Shilenkova, V V; Bestolkova, O S

    2013-01-01

    The objective of the present study was the comparative analysis of acoustic parameters of the voice in the subjects of different age groups. The phonetographic analysis involved 85 relatively healthy subjects (40 men and 45 women) divided into two age-matched groups. Group 1 included mature adults at the age of 43-59 years (n=43), group 2 was comprised of the aged and elderly persons (60-85 years, n=42). It was shown that the frequency of the primary tone decreases with age not only in women but also in men even though the decrease is less pronounced in the latter group. The process of ageing is accompanied by the narrowing of the frequency and dynamic range of the voice, the increase of Jitter, and the decrease in the strength of the voice. As a result, the dyshonia severity index (DSI) shifts toward negative values. These changes are more pronounced in women compared with men. Age-specific negative dynamics of maximum phonation time was not documented.

  5. Age related changes in age of starting to smoke.

    PubMed

    Weinkam, J J; Sterling, T D

    1990-01-01

    The Average Age of Starting to Smoke (AASS) has been reported to decline for younger birth cohorts. That apparent decline has been used to support a conclusion of an increase in smoking among younger individuals. However, in some cases the apparent decline is an artifact of the method of computation which arises when the quantity being averaged is related to a quantity used to classify subjects for comparison. In one other case, a second type of error arises because the distribution of smoking initiation with age changed in such a way that the proportion of individuals taking up smoking at older ages declined more rapidly than the proportion starting at younger ages. In fact, comparison of the 1970 National Health Interview Survey (NHIS) to the 1979/80 NHIS shows a uniform decrease in starting to smoke among teens and preteens. Examples are discussed which show that estimates of possible disease related factors actually experienced by a cohort are possible only if other suitable data are available for comparable representative sections of the population at different time periods and for different ages.

  6. Age related changes in age of starting to smoke.

    PubMed

    Weinkam, J J; Sterling, T D

    1990-01-01

    The Average Age of Starting to Smoke (AASS) has been reported to decline for younger birth cohorts. That apparent decline has been used to support a conclusion of an increase in smoking among younger individuals. However, in some cases the apparent decline is an artifact of the method of computation which arises when the quantity being averaged is related to a quantity used to classify subjects for comparison. In one other case, a second type of error arises because the distribution of smoking initiation with age changed in such a way that the proportion of individuals taking up smoking at older ages declined more rapidly than the proportion starting at younger ages. In fact, comparison of the 1970 National Health Interview Survey (NHIS) to the 1979/80 NHIS shows a uniform decrease in starting to smoke among teens and preteens. Examples are discussed which show that estimates of possible disease related factors actually experienced by a cohort are possible only if other suitable data are available for comparable representative sections of the population at different time periods and for different ages. PMID:2303843

  7. Age-related changes in matching novel objects across viewpoints

    PubMed Central

    Konar, Yaroslav; Vuong, Quoc C.; Bennett, Patrick J.; Sekuler, Allison B.

    2016-01-01

    Object recognition is an important visual process. We are not only required to recognize objects across a variety of lighting conditions and variations in size, but also across changes in viewpoint. It has been shown that reaction times in object matching increase as a function of increasing angular disparity between two views of the same object, and it is thought that this is related to the time it takes to mentally rotate an object. Recent studies have shown that object rotations for familiar objects affect older subjects differently than younger subjects. To investigate the general normalization effects for recognizing objects across different viewpoints regardless of visual experience with an object, in the current study we used novel 3D stimuli. Older and younger subjects matched objects across a variety of viewpoints along both in-depth and picture-plane rotations. Response times (RTs) for in-depth rotations were generally slower than for picture plane rotations and older subjects, overall, responded slower than younger subjects. However, a male RT advantage was only found for objects that differed by large, in-depth rotations. Compared to younger subjects, older subjects were not only slower but also less accurate at matching objects across both rotation axes. The age effect was primarily due to older male subjects performing worse than younger male subjects, whereas there was no significant age difference for female subjects. In addition, older males performed even worse than older females, which argues against a general male advantage in mental rotations tasks. PMID:21784094

  8. Age-related changes in the performance of forward reach.

    PubMed

    Lin, S I; Liao, C F

    2011-01-01

    Aging is widely considered to be associated with limited balance capacity. It is not clear if forward reach ability is also affected by aging. The purpose of this study was to determine if aging was associated with reduced ability of forward reach or changes in movement patterns. Thirty-three young and 31 older adults were instructed to reach forward as far as possible without losing balance. A motion analysis system was used to record the body kinematics to calculate the joint angle and estimate the motion of center of mass (COM) using a five-segment model. Reach distance (measured from the finger marker), COM displacement, and the distance that the COM exceeded the 2nd toe marker (COM-toe) were used to represent reach performance. The movement patterns were classified as hip, ankle or mixed strategies based upon joint kinematics. It was found that the initial location of the COM was significantly more anterior in the older adults. Older adults were found to have significantly smaller COM displacement and greater hip flexion, but did not differ from young adults in reach distance or COM-toe. Older adults overwhelmingly adopted a hip strategy, but none adopted an ankle strategy. The distribution of the different strategies also differed significantly between groups. These findings suggest that aging appears to be associated with modifications in movement patterns, but not necessarily with a reduction in the ability to approach the boundary of stability. Clinically, balance training for older adults may include the exploration and instruction of atypical movement patterns. PMID:20951591

  9. Longitudinal Attentional Engagement Rescues Mice from Age-Related Cognitive Declines and Cognitive Inflexibility

    ERIC Educational Resources Information Center

    Matzel, Louis D.; Light, Kenneth R.; Wass, Christopher; Colas-Zelin, Danielle; Denman-Brice, Alexander; Waddel, Adam C.; Kolata, Stefan

    2011-01-01

    Learning, attentional, and perseverative deficits are characteristic of cognitive aging. In this study, genetically diverse CD-1 mice underwent longitudinal training in a task asserted to tax working memory capacity and its dependence on selective attention. Beginning at 3 mo of age, animals were trained for 12 d to perform in a dual radial-arm…

  10. Impact of the hypothalamic-pituitary-adrenal/gonadal axes on trajectory of age-related cognitive decline.

    PubMed

    Conrad, Cheryl D; Bimonte-Nelson, Heather A

    2010-01-01

    Life expectancies have increased substantially in the last century, dramatically amplifying the proportion of individuals who will reach old age. As individuals age, cognitive ability declines, although the rate of decline differs amongst the forms of memory domains and for different individuals. Memory domains especially impacted by aging are declarative and spatial memories. The hippocampus facilitates the formation of declarative and spatial memories. Notably, the hippocampus is particularly vulnerable to aging. Genetic predisposition and lifetime experiences and exposures contribute to the aging process, brain changes and subsequent cognitive outcomes. In this review, two factors to which an individual is exposed, the hypothalamic-pituitary-adrenal (HPA) axis and the hypothalamic-pituitary-gonadal (HPG) axis, will be considered regarding the impact of age on hippocampal-dependent function. Spatial memory can be affected by cumulative exposure to chronic stress via glucocorticoids, released from the HPA axis, and from gonadal steroids (estrogens, progesterone and androgens) and gonadotrophins, released from the HPG axis. Additionally, this review will discuss how these hormones impact age-related hippocampal function. We hypothesize that lifetime experiences and exposure to these hormones contribute to the cognitive makeup of the aged individual, and contribute to the heterogeneous aged population that includes individuals with cognitive abilities as astute as their younger counterparts, as well as individuals with severe cognitive decline or neurodegenerative disease.

  11. Jumping Stand Apparatus Reveals Rapidly Specific Age-Related Cognitive Impairments in Mouse Lemur Primates.

    PubMed

    Picq, Jean-Luc; Villain, Nicolas; Gary, Charlotte; Pifferi, Fabien; Dhenain, Marc

    2015-01-01

    The mouse lemur (Microcebus murinus) is a promising primate model for investigating normal and pathological cerebral aging. The locomotor behavior of this arboreal primate is characterized by jumps to and from trunks and branches. Many reports indicate insufficient adaptation of the mouse lemur to experimental devices used to evaluate its cognition, which is an impediment to the efficient use of this animal in research. In order to develop cognitive testing methods appropriate to the behavioral and biological traits of this species, we adapted the Lashley jumping stand apparatus, initially designed for rats, to the mouse lemur. We used this jumping stand apparatus to compare performances of young (n = 12) and aged (n = 8) adults in acquisition and long-term retention of visual discriminations. All mouse lemurs completed the tasks and only 25 trials, on average, were needed to master the first discrimination problem with no age-related differences. A month later, all mouse lemurs made progress for acquiring the second discrimination problem but only the young group reached immediately the criterion in the retention test of the first discrimination problem. This study shows that the jumping stand apparatus allows rapid and efficient evaluation of cognition in mouse lemurs and demonstrates that about half of the old mouse lemurs display a specific deficit in long-term retention but not in acquisition of visual discrimination.

  12. Jumping Stand Apparatus Reveals Rapidly Specific Age-Related Cognitive Impairments in Mouse Lemur Primates

    PubMed Central

    Picq, Jean-Luc; Villain, Nicolas; Gary, Charlotte; Pifferi, Fabien; Dhenain, Marc

    2015-01-01

    The mouse lemur (Microcebus murinus) is a promising primate model for investigating normal and pathological cerebral aging. The locomotor behavior of this arboreal primate is characterized by jumps to and from trunks and branches. Many reports indicate insufficient adaptation of the mouse lemur to experimental devices used to evaluate its cognition, which is an impediment to the efficient use of this animal in research. In order to develop cognitive testing methods appropriate to the behavioral and biological traits of this species, we adapted the Lashley jumping stand apparatus, initially designed for rats, to the mouse lemur. We used this jumping stand apparatus to compare performances of young (n = 12) and aged (n = 8) adults in acquisition and long-term retention of visual discriminations. All mouse lemurs completed the tasks and only 25 trials, on average, were needed to master the first discrimination problem with no age-related differences. A month later, all mouse lemurs made progress for acquiring the second discrimination problem but only the young group reached immediately the criterion in the retention test of the first discrimination problem. This study shows that the jumping stand apparatus allows rapid and efficient evaluation of cognition in mouse lemurs and demonstrates that about half of the old mouse lemurs display a specific deficit in long-term retention but not in acquisition of visual discrimination. PMID:26716699

  13. Jumping Stand Apparatus Reveals Rapidly Specific Age-Related Cognitive Impairments in Mouse Lemur Primates.

    PubMed

    Picq, Jean-Luc; Villain, Nicolas; Gary, Charlotte; Pifferi, Fabien; Dhenain, Marc

    2015-01-01

    The mouse lemur (Microcebus murinus) is a promising primate model for investigating normal and pathological cerebral aging. The locomotor behavior of this arboreal primate is characterized by jumps to and from trunks and branches. Many reports indicate insufficient adaptation of the mouse lemur to experimental devices used to evaluate its cognition, which is an impediment to the efficient use of this animal in research. In order to develop cognitive testing methods appropriate to the behavioral and biological traits of this species, we adapted the Lashley jumping stand apparatus, initially designed for rats, to the mouse lemur. We used this jumping stand apparatus to compare performances of young (n = 12) and aged (n = 8) adults in acquisition and long-term retention of visual discriminations. All mouse lemurs completed the tasks and only 25 trials, on average, were needed to master the first discrimination problem with no age-related differences. A month later, all mouse lemurs made progress for acquiring the second discrimination problem but only the young group reached immediately the criterion in the retention test of the first discrimination problem. This study shows that the jumping stand apparatus allows rapid and efficient evaluation of cognition in mouse lemurs and demonstrates that about half of the old mouse lemurs display a specific deficit in long-term retention but not in acquisition of visual discrimination. PMID:26716699

  14. Over the hill at 24: persistent age-related cognitive-motor decline in reaction times in an ecologically valid video game task begins in early adulthood.

    PubMed

    Thompson, Joseph J; Blair, Mark R; Henrey, Andrew J

    2014-01-01

    Typically studies of the effects of aging on cognitive-motor performance emphasize changes in elderly populations. Although some research is directly concerned with when age-related decline actually begins, studies are often based on relatively simple reaction time tasks, making it impossible to gauge the impact of experience in compensating for this decline in a real world task. The present study investigates age-related changes in cognitive motor performance through adolescence and adulthood in a complex real world task, the real-time strategy video game StarCraft 2. In this paper we analyze the influence of age on performance using a dataset of 3,305 players, aged 16-44, collected by Thompson, Blair, Chen & Henrey [1]. Using a piecewise regression analysis, we find that age-related slowing of within-game, self-initiated response times begins at 24 years of age. We find no evidence for the common belief expertise should attenuate domain-specific cognitive decline. Domain-specific response time declines appear to persist regardless of skill level. A second analysis of dual-task performance finds no evidence of a corresponding age-related decline. Finally, an exploratory analyses of other age-related differences suggests that older participants may have been compensating for a loss in response speed through the use of game mechanics that reduce cognitive load.

  15. Over the Hill at 24: Persistent Age-Related Cognitive-Motor Decline in Reaction Times in an Ecologically Valid Video Game Task Begins in Early Adulthood

    PubMed Central

    Thompson, Joseph J.; Blair, Mark R.; Henrey, Andrew J.

    2014-01-01

    Typically studies of the effects of aging on cognitive-motor performance emphasize changes in elderly populations. Although some research is directly concerned with when age-related decline actually begins, studies are often based on relatively simple reaction time tasks, making it impossible to gauge the impact of experience in compensating for this decline in a real world task. The present study investigates age-related changes in cognitive motor performance through adolescence and adulthood in a complex real world task, the real-time strategy video game StarCraft 2. In this paper we analyze the influence of age on performance using a dataset of 3,305 players, aged 16-44, collected by Thompson, Blair, Chen & Henrey [1]. Using a piecewise regression analysis, we find that age-related slowing of within-game, self-initiated response times begins at 24 years of age. We find no evidence for the common belief expertise should attenuate domain-specific cognitive decline. Domain-specific response time declines appear to persist regardless of skill level. A second analysis of dual-task performance finds no evidence of a corresponding age-related decline. Finally, an exploratory analyses of other age-related differences suggests that older participants may have been compensating for a loss in response speed through the use of game mechanics that reduce cognitive load. PMID:24718593

  16. Over the hill at 24: persistent age-related cognitive-motor decline in reaction times in an ecologically valid video game task begins in early adulthood.

    PubMed

    Thompson, Joseph J; Blair, Mark R; Henrey, Andrew J

    2014-01-01

    Typically studies of the effects of aging on cognitive-motor performance emphasize changes in elderly populations. Although some research is directly concerned with when age-related decline actually begins, studies are often based on relatively simple reaction time tasks, making it impossible to gauge the impact of experience in compensating for this decline in a real world task. The present study investigates age-related changes in cognitive motor performance through adolescence and adulthood in a complex real world task, the real-time strategy video game StarCraft 2. In this paper we analyze the influence of age on performance using a dataset of 3,305 players, aged 16-44, collected by Thompson, Blair, Chen & Henrey [1]. Using a piecewise regression analysis, we find that age-related slowing of within-game, self-initiated response times begins at 24 years of age. We find no evidence for the common belief expertise should attenuate domain-specific cognitive decline. Domain-specific response time declines appear to persist regardless of skill level. A second analysis of dual-task performance finds no evidence of a corresponding age-related decline. Finally, an exploratory analyses of other age-related differences suggests that older participants may have been compensating for a loss in response speed through the use of game mechanics that reduce cognitive load. PMID:24718593

  17. Enriched childhood experiences moderate age-related motor and cognitive decline.

    PubMed

    Metzler, Megan J; Saucier, Deborah M; Metz, Gerlinde A

    2013-01-01

    Aging is associated with deterioration of skilled manual movement. Specifically, aging corresponds with increased reaction time, greater movement duration, segmentation of movement, increased movement variability, and reduced ability to adapt to external forces and inhibit previously learned sequences. Moreover, it is thought that decreased lateralization of neural function in older adults may point to increased neural recruitment as a compensatory response to deterioration of key frontal and intra-hemispheric networks, particularly of callosal structures. However, factors that mediate age-related motor decline are not well understood. Here we show that music training in childhood is associated with reduced age-related decline of bimanual and unimanual motor skills in a MIDI keyboard motor learning task. Compared to older adults without music training, older adults with more than a year of music training demonstrated proficient bimanual and unimanual movement, evidenced by enhanced speed and decreased movement errors. Further, this group demonstrated significantly better implicit learning in the weather prediction task, a non-motor task. The performance of older adults with music training in those tasks was comparable to young adults. Older adults, however, displayed greater verbal ability compared to young adults irrespective of a past history of music training. Our results indicate that music training early in life may reduce age-associated decline of neural motor and cognitive networks.

  18. Enriched childhood experiences moderate age-related motor and cognitive decline

    PubMed Central

    Metzler, Megan J.; Saucier, Deborah M.; Metz, Gerlinde A.

    2012-01-01

    Aging is associated with deterioration of skilled manual movement. Specifically, aging corresponds with increased reaction time, greater movement duration, segmentation of movement, increased movement variability, and reduced ability to adapt to external forces and inhibit previously learned sequences. Moreover, it is thought that decreased lateralization of neural function in older adults may point to increased neural recruitment as a compensatory response to deterioration of key frontal and intra-hemispheric networks, particularly of callosal structures. However, factors that mediate age-related motor decline are not well understood. Here we show that music training in childhood is associated with reduced age-related decline of bimanual and unimanual motor skills in a MIDI keyboard motor learning task. Compared to older adults without music training, older adults with more than a year of music training demonstrated proficient bimanual and unimanual movement, evidenced by enhanced speed and decreased movement errors. Further, this group demonstrated significantly better implicit learning in the weather prediction task, a non-motor task. The performance of older adults with music training in those tasks was comparable to young adults. Older adults, however, displayed greater verbal ability compared to young adults irrespective of a past history of music training. Our results indicate that music training early in life may reduce age-associated decline of neural motor and cognitive networks. PMID:23423702

  19. College Students' Attitudes towards Age-Related Changes in Physical Appearance.

    ERIC Educational Resources Information Center

    Kanter, Allison; Agliata, Daniel; Tantleff-Dunn, Stacey

    The aim of this study was to identify factors associated with young adults' concerns about age related changes in body image and their anticipated impact on psychosocial functioning. One hundred and sixty-seven college students completed the Body Image and Aging Survey, designed to assess age related issues in body image, the Peer Dieting Survey,…

  20. Lower cognitive function in patients with age-related macular degeneration: a meta-analysis

    PubMed Central

    Zhou, Li-Xiao; Sun, Cheng-Lin; Wei, Li-Juan; Gu, Zhi-Min; Lv, Liang; Dang, Yalong

    2016-01-01

    Objective To investigate the cognitive impairment in patients with age-related macular degeneration (AMD). Methods Relevant articles were identified through a search of the following electronic databases through October 2015, without language restriction: 1) PubMed; 2) the Cochrane Library; 3) EMBASE; 4) ScienceDirect. Meta-analysis was conducted using STATA 12.0 software. Standardized mean differences with corresponding 95% confidence intervals were calculated. All of the included studies met the following four criteria: 1) the study design was a case–control or randomized controlled trial (RCT) study; 2) the study investigated cognitive function in the patient with AMD; 3) the diagnoses of AMD must be provided; 4) there were sufficient scores data to extract for evaluating cognitive function between cases and controls. The Newcastle–Ottawa Scale criteria were used to assess the methodological quality of the studies. Results Of the initial 278 literatures, only six case–control and one RCT studies met all of the inclusion criteria. A total of 794 AMD patients and 1,227 controls were included in this study. Five studies were performed with mini-mental state examination (MMSE), two studies with animal fluency, two studies with trail making test (TMT)-A and -B, one study with Mini-Cog. Results of the meta-analysis revealed lower cognitive function test scores in patients with AMD, especially with MMSE and Mini-Cog test (P≤0.001 for all). The results also showed that differences in the TMT-A (except AMD [total] vs controls) and TMT-B test had no statistical significance (P>0.01). The Newcastle–Ottawa Scale score was ≥5 for all of the included studies. Based on the sensitivity analysis, no single study influenced the overall pooled estimates. Conclusion This meta-analysis suggests lower cognitive function test scores in patients with AMD, especially with MMSE and Mini-Cog test. The other cognitive impairment screening tests, such as animal fluency test and

  1. Age-Related Differences in Functional Connectivity During Cognitive Emotion Regulation

    PubMed Central

    Kensinger, Elizabeth A.

    2014-01-01

    Objectives. Successful emotion regulation partly depends on our capacity to modulate emotional responses through the use of cognitive strategies. Age may affect the strategies employed most often; thus, we examined younger and older adults’ neural network connectivity when employing two different strategies: cognitive reappraisal and selective attention. Method. The current study used psychophysiological interaction analyses to examine functional connectivity with a region of anterior cingulate cortex (ACC) because it is a core part of an emotion regulation network showing relative structural preservation with age. Results. Functional connectivity between ACC and prefrontal cortex (PFC) was greater for reappraisal relative to selective attention and passive viewing conditions for both age groups. For younger adults, ACC was more strongly connected with lateral dorsolateral PFC, ventrolateral PFC, dorsomedial PFC, and posterior cingulate regions during reappraisal. For older adults, stronger connectivity during reappraisal was observed primarily in ventromedial PFC and orbitofrontal cortex. Discussion. Our results suggest that although young and older adults engage PFC networks during regulation, and particularly during reappraisal, the regions within these networks might differ. Additionally, these results clarify that, despite prior evidence for age-related declines in the structure and function of those regions, older adults are able to recruit ACC and PFC regions as part of coherent network during emotion regulation. PMID:25209373

  2. ROLE OF SOLUBLE EPOXIDE HYDROLASE IN AGE-RELATED VASCULAR COGNITIVE DECLINE

    PubMed Central

    Nelson, Jonathan W.; Young, Jennifer M.; Borkar, Rohan; Woltjer, Randy L.; Quinn, Joseph F.; Silbert, Lisa C.; Grafe, Marjorie R.; Alkayed, Nabil J.

    2014-01-01

    P450 eicosanoids are important regulators of the cerebral microcirculation, but their role in cerebral small vessel disease is unclear. We tested the hypothesis that vascular cognitive impairment (VCI) is linked to reduced cerebral microvascular eicosanoid signaling. We analyzed human brain tissue from individuals formerly enrolled in the Oregon Brain Aging Study, who had a history of cognitive impairment histopathological evidence of microvascular disease. VCI subjects had significantly higher lesion burden both on premortem MRI and postmortem histopathology compared to age- and sex-matched controls. Mass spectrometry-based eicosanoid analysis revealed that 14,15-dihydroxyeicosatrienoic acid (DHET) was elevated in cortical brain tissue from VCI subjects. Immunoreactivity of soluble epoxide hydrolase (sEH), the enzyme responsible for 14,15-DHET formation, was localized to cerebral microvascular endothelium, and was enhanced in microvessels of affected tissue. Finally, we evaluated the genotype frequency of two functional single nucleotide polymorphisms of sEH gene EPHX2 in VCI and control groups. Our findings support a role for sEH and a potential benefit from sEH inhibitors in age-related VCI. PMID:25277097

  3. Aging Changes in Retinal Microglia and their Relevance to Age-related Retinal Disease.

    PubMed

    Ma, Wenxin; Wong, Wai T

    2016-01-01

    Age-related retinal diseases, such as age-related macular degeneration (AMD) and glaucoma, contain features of chronic retinal inflammation that may promote disease progression. However, the relationship between aging and neuroinflammation is unclear. Microglia are long-lived, resident immune cells of the retina, and mediate local neuroinflammatory reactions. We hypothesize that aging changes in microglia may be causally linked to neuroinflammatory changes underlying age-dependent retinal diseases. Here, we review the evidence for (1) how the retinal microglial phenotype changes with aging, (2) the factors that drive microglial aging in the retina, and (3) aging-related changes in microglial gene expression. We examine how these aspects of microglial aging changes may relate to pathogenic mechanisms of immune dysregulation driving the progression of age-related retinal disease. These relationships can highlight microglial aging as a novel target for the prevention and treatment of retinal disease.

  4. Cognitive aging explains age-related differences in face-based recognition of basic emotions except for anger and disgust.

    PubMed

    Suzuki, Atsunobu; Akiyama, Hiroko

    2013-01-01

    This study aimed at a detailed understanding of the possible dissociable influences of cognitive aging on the recognition of facial expressions of basic emotions (happiness, surprise, fear, anger, disgust, and sadness). The participants were 36 older and 36 young adults. They viewed 96 pictures of facial expressions and were asked to choose one emotion that best described each. Four cognitive tasks measuring the speed of processing and fluid intelligence were also administered, the scores of which were used to compute a composite measure of general cognitive ability. A series of hierarchical regression analyses revealed that age-related deficits in identifying happiness, surprise, fear, and sadness were statistically explained by general cognitive ability, while the differences in anger and disgust were not. This provides clear evidence that age-related cognitive impairment remarkably and differentially affects the recognition of basic emotions, contrary to the common view that cognitive aging has a uniformly minor effect.

  5. AGE-RELATED GENE EXPRESSION CHANGES IN HUMAN SKIN FIBROBLASTS INDUCED BY MMS

    EPA Science Inventory

    Age-Related Gene Expression Changes In Human Skin Fibroblasts Induced By methyl methanesulfonate. Geremy W. Knapp, Alan H. Tennant, and Russell D. Owen. Environmental Carcinogenesis Division, National Health and Environmental Effects Research Laboratory, U. S. Environmental Prote...

  6. Ex vivo T2 relaxation: associations with age-related neuropathology and cognition.

    PubMed

    Dawe, Robert J; Bennett, David A; Schneider, Julie A; Leurgans, Sue E; Kotrotsou, Aikaterini; Boyle, Patricia A; Arfanakis, Konstantinos

    2014-07-01

    The transverse relaxation time constant, T(2), is sensitive to brain tissue's free water content and the presence of paramagnetic materials such as iron. In this study, ex vivo magnetic resonance imaging was used to investigate alterations in T(2) related to Alzheimer's disease (AD) pathology and other types of neuropathology common in old age, as well as the relationship between T(2) alterations and cognition. Cerebral hemispheres were obtained from 371 deceased older adults. Using fast spin-echo imaging with multiple echo times, T(2) maps were produced and warped to a study-specific template. Hemispheres underwent neuropathologic examination for identification of AD pathology and other common age-related neuropathologies. Voxelwise linear regression was carried out to detect regions of pathology-related T(2) alterations and, in separate analyses, regions in which T(2) alterations were linked to antemortem cognitive performance. AD pathology was associated with T(2) prolongation in white matter of all lobes and T(2) shortening in the basal ganglia and insula. Gross infarcts were associated with T(2) prolongation in white matter of all lobes, and in the thalamus and basal ganglia. Hippocampal sclerosis was associated with T(2) prolongation in the hippocampus and white matter of the temporal lobe. After controlling for neuropathology, T(2) prolongation in the frontal lobe white matter was associated with lower performance in the episodic, semantic, and working memory domains. In addition, voxelwise analysis of in vivo and ex vivo T(2) values indicated a positive relationship between the two, though further investigation is necessary to accurately translate findings of the present study to the in vivo case.

  7. The Digital Ageing Atlas: integrating the diversity of age-related changes into a unified resource.

    PubMed

    Craig, Thomas; Smelick, Chris; Tacutu, Robi; Wuttke, Daniel; Wood, Shona H; Stanley, Henry; Janssens, Georges; Savitskaya, Ekaterina; Moskalev, Alexey; Arking, Robert; de Magalhães, João Pedro

    2015-01-01

    Multiple studies characterizing the human ageing phenotype have been conducted for decades. However, there is no centralized resource in which data on multiple age-related changes are collated. Currently, researchers must consult several sources, including primary publications, in order to obtain age-related data at various levels. To address this and facilitate integrative, system-level studies of ageing we developed the Digital Ageing Atlas (DAA). The DAA is a one-stop collection of human age-related data covering different biological levels (molecular, cellular, physiological, psychological and pathological) that is freely available online (http://ageing-map.org/). Each of the >3000 age-related changes is associated with a specific tissue and has its own page displaying a variety of information, including at least one reference. Age-related changes can also be linked to each other in hierarchical trees to represent different types of relationships. In addition, we developed an intuitive and user-friendly interface that allows searching, browsing and retrieving information in an integrated and interactive fashion. Overall, the DAA offers a new approach to systemizing ageing resources, providing a manually-curated and readily accessible source of age-related changes.

  8. The Digital Ageing Atlas: integrating the diversity of age-related changes into a unified resource

    PubMed Central

    Craig, Thomas; Smelick, Chris; Tacutu, Robi; Wuttke, Daniel; Wood, Shona H.; Stanley, Henry; Janssens, Georges; Savitskaya, Ekaterina; Moskalev, Alexey; Arking, Robert; de Magalhães, João Pedro

    2015-01-01

    Multiple studies characterizing the human ageing phenotype have been conducted for decades. However, there is no centralized resource in which data on multiple age-related changes are collated. Currently, researchers must consult several sources, including primary publications, in order to obtain age-related data at various levels. To address this and facilitate integrative, system-level studies of ageing we developed the Digital Ageing Atlas (DAA). The DAA is a one-stop collection of human age-related data covering different biological levels (molecular, cellular, physiological, psychological and pathological) that is freely available online (http://ageing-map.org/). Each of the >3000 age-related changes is associated with a specific tissue and has its own page displaying a variety of information, including at least one reference. Age-related changes can also be linked to each other in hierarchical trees to represent different types of relationships. In addition, we developed an intuitive and user-friendly interface that allows searching, browsing and retrieving information in an integrated and interactive fashion. Overall, the DAA offers a new approach to systemizing ageing resources, providing a manually-curated and readily accessible source of age-related changes. PMID:25232097

  9. A Brain-Wide Study of Age-Related Changes in Functional Connectivity.

    PubMed

    Geerligs, Linda; Renken, Remco J; Saliasi, Emi; Maurits, Natasha M; Lorist, Monicque M

    2015-07-01

    Aging affects functional connectivity between brain areas, however, a complete picture of how aging affects integration of information within and between functional networks is missing. We used complex network measures, derived from a brain-wide graph, to provide a comprehensive overview of age-related changes in functional connectivity. Functional connectivity in young and older participants was assessed during resting-state fMRI. The results show that aging has a large impact, not only on connectivity within functional networks but also on connectivity between the different functional networks in the brain. Brain networks in the elderly showed decreased modularity (less distinct functional networks) and decreased local efficiency. Connectivity decreased with age within networks supporting higher level cognitive functions, that is, within the default mode, cingulo-opercular and fronto-parietal control networks. Conversely, no changes in connectivity within the somatomotor and visual networks, networks implicated in primary information processing, were observed. Connectivity between these networks even increased with age. A brain-wide analysis approach of functional connectivity in the aging brain thus seems fundamental in understanding how age affects integration of information.

  10. Dimensional change card sort performance associated with age-related differences in functional connectivity of lateral prefrontal cortex.

    PubMed

    Ezekiel, Fredrick; Bosma, Rachael; Morton, J Bruce

    2013-07-01

    The Dimensional Change Card Sort (DCCS) is a standard procedure for assessing executive functioning early in development. In the task, participants switch from sorting cards one way (e.g., by color) to sorting them a different way (e.g., by shape). Traditional accounts associate age-related changes in DCCS performance with circumscribed changes in lateral prefrontal cortex (lPFC) functioning, but evidence of age-related differences in the modulation of lPFC activity by switching is mixed. The current study therefore tested for possible age-related differences in functional connectivity of lPFC with regions that comprise a larger cognitive control network. Functional magnetic resonance imaging (fMRI) data collected from children and adults performing the DCCS were analyzed by means of independent components analysis (ICA). The analysis revealed several important age-related differences in functional connectivity of lPFC. In particular, lPFC was more strongly connected with the anterior cingulate, inferior parietal cortex, and the ventral tegmental area in adults than in children. Theoretical implications are discussed. PMID:23328350

  11. Understanding Age-Related Changes in Skeletal Muscle Metabolism: Differences Between Females and Males.

    PubMed

    Gheller, Brandon J F; Riddle, Emily S; Lem, Melinda R; Thalacker-Mercer, Anna E

    2016-07-17

    Skeletal muscle is the largest metabolic organ system in the human body. As such, metabolic dysfunction occurring in skeletal muscle impacts whole-body nutrient homeostasis. Macronutrient metabolism changes within the skeletal muscle with aging, and these changes are associated in part with age-related skeletal muscle remodeling. Moreover, age-related changes in skeletal muscle metabolism are affected differentially between males and females and are likely driven by changes in sex hormones. Intrinsic and extrinsic factors impact observed age-related changes and sex-related differences in skeletal muscle metabolism. Despite some support for sex-specific differences in skeletal muscle metabolism with aging, more research is necessary to identify underlying differences in mechanisms. Understanding sex-specific aging skeletal muscle will assist with the development of therapies to attenuate adverse metabolic and functional outcomes.

  12. Age-related changes in learning across early childhood: a new imitation task.

    PubMed

    Dickerson, Kelly; Gerhardstein, Peter; Zack, Elizabeth; Barr, Rachel

    2013-11-01

    Imitation plays a critical role in social and cognitive development, but the social learning mechanisms contributing to the development of imitation are not well understood. We developed a new imitation task designed to examine social learning mechanisms across the early childhood period. The new task involves assembly of abstract-shaped puzzle pieces in an arbitrary sequence on a magnet board. Additionally, we introduce a new scoring system that extends traditional goal-directed imitation scoring to include measures of both children's success at copying gestures (sliding the puzzle pieces) and goals (connecting the puzzle pieces). In Experiment 1, we demonstrated an age-invariant baseline from 1.5 to 3.5 years of age, accompanied by age-related changes in success at copying goals and gestures from a live demonstrator. In Experiment 2, we applied our new task to learning following a video demonstration. Imitation performance in the video demonstration group lagged behind that of the live demonstration group, showing a protracted video deficit effect. Across both experiments, children were more likely to copy gestures at earlier ages, suggesting mimicry, and only later copy both goals and gestures, suggesting imitation. Taken together, the findings suggest that different social learning strategies may predominate in imitation learning dependent upon the degree of object affordance, task novelty, and task complexity. PMID:22786801

  13. Age-related changes to oscillatory dynamics in hippocampal and neocortical networks.

    PubMed

    Rondina, Renante; Olsen, Rosanna K; McQuiggan, Douglas A; Fatima, Zainab; Li, Lingqian; Oziel, Esther; Meltzer, Jed A; Ryan, Jennifer D

    2016-10-01

    Recent models of hippocampal function have emphasized its role in relational binding - the ability to form lasting representations regarding the relations among distinct elements or items which can support memory performance, even over brief delays (e.g., several seconds). The present study examined the extent to which aging is associated with changes in the recruitment of oscillatory activity within hippocampal and neocortical regions to support relational binding performance on a short delay visuospatial memory task. Structural magnetic resonance imaging and MEG were used to characterize potential age-related changes in hippocampal volume, oscillatory activity, and subsequent memory performance, and the relationships among them. Participants were required to bind the relative visuospatial positions of objects that were presented singly across time. Subsequently, the objects were re-presented simultaneously, and participants were required to indicate whether the relative spatial positions among the objects had been maintained. Older and younger adults demonstrated similar task accuracy, and older adults had preserved hippocampal volumes relative to younger adults. Age-group differences were found in pre-stimulus theta (∼5Hz) and beta (∼20Hz) oscillations, and this pre-stimulus activity was related to hippocampal volumes in younger adults. Age-group differences were also found in the recruitment of oscillatory activity from the pre-stimulus period to the task. Only younger adults showed a task-related change in theta power that was predictive of memory performance. In contrast, older adults demonstrated task-related alpha (∼10Hz) oscillatory power changes that were not observed in younger adults. These findings provide novel evidence for the role of the hippocampus and functionally connected regions in relational binding that is disrupted in aging. The present findings are discussed in the context of current models regarding the cognitive neuroscience of

  14. Age-related changes to oscillatory dynamics in hippocampal and neocortical networks.

    PubMed

    Rondina, Renante; Olsen, Rosanna K; McQuiggan, Douglas A; Fatima, Zainab; Li, Lingqian; Oziel, Esther; Meltzer, Jed A; Ryan, Jennifer D

    2016-10-01

    Recent models of hippocampal function have emphasized its role in relational binding - the ability to form lasting representations regarding the relations among distinct elements or items which can support memory performance, even over brief delays (e.g., several seconds). The present study examined the extent to which aging is associated with changes in the recruitment of oscillatory activity within hippocampal and neocortical regions to support relational binding performance on a short delay visuospatial memory task. Structural magnetic resonance imaging and MEG were used to characterize potential age-related changes in hippocampal volume, oscillatory activity, and subsequent memory performance, and the relationships among them. Participants were required to bind the relative visuospatial positions of objects that were presented singly across time. Subsequently, the objects were re-presented simultaneously, and participants were required to indicate whether the relative spatial positions among the objects had been maintained. Older and younger adults demonstrated similar task accuracy, and older adults had preserved hippocampal volumes relative to younger adults. Age-group differences were found in pre-stimulus theta (∼5Hz) and beta (∼20Hz) oscillations, and this pre-stimulus activity was related to hippocampal volumes in younger adults. Age-group differences were also found in the recruitment of oscillatory activity from the pre-stimulus period to the task. Only younger adults showed a task-related change in theta power that was predictive of memory performance. In contrast, older adults demonstrated task-related alpha (∼10Hz) oscillatory power changes that were not observed in younger adults. These findings provide novel evidence for the role of the hippocampus and functionally connected regions in relational binding that is disrupted in aging. The present findings are discussed in the context of current models regarding the cognitive neuroscience of

  15. Processing Speed, Inhibitory Control, and Working Memory: Three Important Factors to Account for Age-Related Cognitive Decline

    ERIC Educational Resources Information Center

    Pereiro Rozas, Arturo X.; Juncos-Rabadan, Onesimo; Gonzalez, Maria Soledad Rodriguez

    2008-01-01

    Processing speed, inhibitory control and working memory have been identified as the main possible culprits of age-related cognitive decline. This article describes a study of their interrelationships and dependence on age, including exploration of whether any of them mediates between age and the others. We carried out a LISREL analysis of the…

  16. Correcting age-related changes in the face by use of injectable fillers and neurotoxins.

    PubMed

    Rubin, Mark G; Cox, Sue Ellen; Kaminer, Michael S; Solish, Nowell

    2014-06-01

    Many patients seeking rejuvenation treatment have readily apparent age-related changes in facial features. Others exhibit more subtle changes that nonetheless can be corrected to achieve a more youthful appearance. In the following article, four specialists in aesthetic dermatology discuss how injectable hyaluronic acid-based fillers and neurotoxins can achieve rejuvenation without surgery.

  17. [Age-related cognitive impairment: conceptual changes and diagnostic strategies].

    PubMed

    Annoni, Jean-Marie; Chouiter, Leila; Démonet, Jean-François

    2016-04-20

    The actual field of dementia encompasses also the pre-symptomatic phase, which may evolve for decades. Early detection and appropriate diagnosis decrease patient's and family's anxiety, improve patient's global care and allow better legal patient's protection. General Practitioners have at hand several available tools to screen a neurocognitive disorder, with up to 80% of sensitivity and specificity, to complete their clinical evaluation. An accurate diagnosis requires then a complete medical, neurological neuropsychological and neuroradiological evaluation in a Memory Clinic. Other investigations, such as functional cerebral imagery and spinal tap can be critical in unusual situations. Despite mood improvement after diagnostic announcement, increased suicidal risk in the 3 first months should be screened. PMID:27276719

  18. News of cognitive cure for age-related brain shrinkage is premature: a comment on Burgmans et al. (2009).

    PubMed

    Raz, Naftali; Lindenberger, Ulman

    2010-03-01

    The extant longitudinal literature consistently supports the notion of age-related declines in human brain volume. In a report on a longitudinal cognitive follow-up with cross-sectional brain measurements, Burgmans and colleagues (2009) claim that the extant studies overestimate brain volume declines, presumably due to inclusion of participants with preclinical cognitive pathology. Moreover, the authors of the article assert that such declines are absent among optimally healthy adults who maintain cognitive stability for several years. In this comment accompanied by reanalysis of previously published data, we argue that these claims are incorrect on logical, methodological, and empirical grounds. PMID:20230118

  19. Age-Related Changes in Duration Reproduction: Involvement of Working Memory Processes

    ERIC Educational Resources Information Center

    Baudouin, Alexia; Vanneste, Sandrine; Pouthas, Viviane; Isingrini, Michel

    2006-01-01

    The aim of the present research was to study age-related changes in duration reproduction by differentiating the working memory processes underlying this time estimation task. We compared performances of young and elderly adults in a duration reproduction task performed in simple and concurrent task conditions. Participants were also administered…

  20. Children's Recognition of Fairness and Others' Welfare in a Resource Allocation Task: Age Related Changes

    ERIC Educational Resources Information Center

    Rizzo, Michael T.; Elenbaas, Laura; Cooley, Shelby; Killen, Melanie

    2016-01-01

    The present study investigated age-related changes regarding children's (N = 136) conceptions of fairness and others' welfare in a merit-based resource allocation paradigm. To test whether children at 3- to 5-years-old and 6- to 8-years-old took others' welfare into account when dividing resources, in addition to merit and equality concerns,…

  1. Heritability of Anxious-Depressive and Withdrawn Behavior: Age-Related Changes during Adolescence

    ERIC Educational Resources Information Center

    Lamb, Diane J.; Middeldorp, Christel M.; van Beijsterveldt, Catarina E. M.; Bartels, Meike; van der Aa, Niels; Polderman, Tinca J. C.; Boomsma, Dorret I.

    2010-01-01

    Objective: To explain the differential course of anxiety and depression in individuals from childhood to adulthood by examining age-related changes in the genetic and environmental etiology of anxious and depressive symptoms. Method: A sample of 1470, 1839, and 2023 Dutch twins aged 12, 14, and 16 years reported on symptoms of anxious depression…

  2. Reduced writing and reading speed and age-related changes in verbal fluency tasks.

    PubMed

    Rodríguez-Aranda, Claudia

    2003-05-01

    The present study examined the influence of age-related decline in psychomotor speed on verbal fluency tasks. Reading speed, handwriting speed, written fluency, oral fluency, vocabulary, and years of formal education were measured in a sample of healthy volunteers (N=101) ranging in age from 20 to 88 years. Multiple regression analyses revealed that reading and handwriting speed strongly predicted verbal fluency performance. These measures, together with vocabulary skills and mental status, were significant predictors of performance on the fluency tasks. Present results suggest that decrement in verbal fluency performance in the aged may, at least partially, be due to reduced psychomotor speed rather than to decline in linguistic or cognitive functions.

  3. Inflammatory insult during pregnancy accelerates age-related behavioral and neurobiochemical changes in CD-1 mice.

    PubMed

    Li, Xue-Yan; Wang, Fang; Chen, Gui-Hai; Li, Xue-Wei; Yang, Qi-Gang; Cao, Lei; Yan, Wen-Wen

    2016-06-01

    Data shows that inflammation during pregnancy significantly exerts a long-term influence on offspring, such as increasing the risk of adult cognition decline in animals. However, it is unclear whether gestational inflammation affects the neurobehavioral and neurobiochemical outcomes in the mother-self during aging. In this study, pregnant CD-1 mice intraperitoneally received lipopolysaccharide (LPS) in two doses (25 and 50 g/kg, respectively) or normal saline daily during gestational days 15-17. At the age of 15 months, a battery of behavioral tasks was employed to evaluate their species-typical behaviors, sensorimotor ability, anxiety levels, and spatial learning and memory abilities. An immunohistochemical method was utilized preliminarily to detect neurobiochemical indicators consisting of amyloid-β, phosphorylated tau, presynaptic proteins synaptotagmin-1 and syntaxin-1, glial fibrillary acidic protein (GFAP), and histone-4 acetylation on the K8 site (H4K8ac). The behavioral results showed that LPS exposure during pregnancy exacerbated a decline in 15-month-old CD-1 mice's abilities to nest, their sensorimotor and spatial learning and memory capabilities, and increased their anxiety levels. The neurobiochemical results indicated that gestational LPS exposure also intensified age-related hippocampal changes, including increased amyloid-β42, phosphorylated tau, synaptotagmin-1 and GFAP, and decreased syntaxin-1 and H4K8ac. Our results suggested that the inflammatory insult during pregnancy could be an important risk factor for the development of Alzheimer's disease, and the H4K8 acetylation might play an important role in the underlying mechanism. This study offers a perspective for improving strategies that support healthy development and successful aging.

  4. Age-related changes to the neural correlates of working memory which emerge after midlife

    PubMed Central

    Macpherson, Helen N.; White, David J.; Ellis, Kathryn A.; Stough, Con; Camfield, David; Silberstein, Richard; Pipingas, Andrew

    2014-01-01

    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. PMID:24795625

  5. Genome-wide age-related changes in DNA methylation and gene expression in human PBMCs.

    PubMed

    Steegenga, Wilma T; Boekschoten, Mark V; Lute, Carolien; Hooiveld, Guido J; de Groot, Philip J; Morris, Tiffany J; Teschendorff, Andrew E; Butcher, Lee M; Beck, Stephan; Müller, Michael

    2014-06-01

    Aging is a progressive process that results in the accumulation of intra- and extracellular alterations that in turn contribute to a reduction in health. Age-related changes in DNA methylation have been reported before and may be responsible for aging-induced changes in gene expression, although a causal relationship has yet to be shown. Using genome-wide assays, we analyzed age-induced changes in DNA methylation and their effect on gene expression with and without transient induction with the synthetic transcription modulating agent WY14,643. To demonstrate feasibility of the approach, we isolated peripheral blood mononucleated cells (PBMCs) from five young and five old healthy male volunteers and cultured them with or without WY14,643. Infinium 450K BeadChip and Affymetrix Human Gene 1.1 ST expression array analysis revealed significant differential methylation of at least 5 % (ΔYO > 5 %) at 10,625 CpG sites between young and old subjects, but only a subset of the associated genes were also differentially expressed. Age-related differential methylation of previously reported epigenetic biomarkers of aging including ELOVL2, FHL2, PENK, and KLF14 was confirmed in our study, but these genes did not display an age-related change in gene expression in PBMCs. Bioinformatic analysis revealed that differentially methylated genes that lack an age-related expression change predominantly represent genes involved in carcinogenesis and developmental processes, and expression of most of these genes were silenced in PBMCs. No changes in DNA methylation were found in genes displaying transiently induced changes in gene expression. In conclusion, aging-induced differential methylation often targets developmental genes and occurs mostly without change in gene expression.

  6. Genome-wide age-related changes in DNA methylation and gene expression in human PBMCs.

    PubMed

    Steegenga, Wilma T; Boekschoten, Mark V; Lute, Carolien; Hooiveld, Guido J; de Groot, Philip J; Morris, Tiffany J; Teschendorff, Andrew E; Butcher, Lee M; Beck, Stephan; Müller, Michael

    2014-06-01

    Aging is a progressive process that results in the accumulation of intra- and extracellular alterations that in turn contribute to a reduction in health. Age-related changes in DNA methylation have been reported before and may be responsible for aging-induced changes in gene expression, although a causal relationship has yet to be shown. Using genome-wide assays, we analyzed age-induced changes in DNA methylation and their effect on gene expression with and without transient induction with the synthetic transcription modulating agent WY14,643. To demonstrate feasibility of the approach, we isolated peripheral blood mononucleated cells (PBMCs) from five young and five old healthy male volunteers and cultured them with or without WY14,643. Infinium 450K BeadChip and Affymetrix Human Gene 1.1 ST expression array analysis revealed significant differential methylation of at least 5 % (ΔYO > 5 %) at 10,625 CpG sites between young and old subjects, but only a subset of the associated genes were also differentially expressed. Age-related differential methylation of previously reported epigenetic biomarkers of aging including ELOVL2, FHL2, PENK, and KLF14 was confirmed in our study, but these genes did not display an age-related change in gene expression in PBMCs. Bioinformatic analysis revealed that differentially methylated genes that lack an age-related expression change predominantly represent genes involved in carcinogenesis and developmental processes, and expression of most of these genes were silenced in PBMCs. No changes in DNA methylation were found in genes displaying transiently induced changes in gene expression. In conclusion, aging-induced differential methylation often targets developmental genes and occurs mostly without change in gene expression. PMID:24789080

  7. Age-Related Changes in Predictive Capacity Versus Internal Model Adaptability: Electrophysiological Evidence that Individual Differences Outweigh Effects of Age.

    PubMed

    Bornkessel-Schlesewsky, Ina; Philipp, Markus; Alday, Phillip M; Kretzschmar, Franziska; Grewe, Tanja; Gumpert, Maike; Schumacher, Petra B; Schlesewsky, Matthias

    2015-01-01

    Hierarchical predictive coding has been identified as a possible unifying principle of brain function, and recent work in cognitive neuroscience has examined how it may be affected by age-related changes. Using language comprehension as a test case, the present study aimed to dissociate age-related changes in prediction generation versus internal model adaptation following a prediction error. Event-related brain potentials (ERPs) were measured in a group of older adults (60-81 years; n = 40) as they read sentences of the form "The opposite of black is white/yellow/nice." Replicating previous work in young adults, results showed a target-related P300 for the expected antonym ("white"; an effect assumed to reflect a prediction match), and a graded N400 effect for the two incongruous conditions (i.e. a larger N400 amplitude for the incongruous continuation not related to the expected antonym, "nice," versus the incongruous associated condition, "yellow"). These effects were followed by a late positivity, again with a larger amplitude in the incongruous non-associated versus incongruous associated condition. Analyses using linear mixed-effects models showed that the target-related P300 effect and the N400 effect for the incongruous non-associated condition were both modulated by age, thus suggesting that age-related changes affect both prediction generation and model adaptation. However, effects of age were outweighed by the interindividual variability of ERP responses, as reflected in the high proportion of variance captured by the inclusion of by-condition random slopes for participants and items. We thus argue that - at both a neurophysiological and a functional level - the notion of general differences between language processing in young and older adults may only be of limited use, and that future research should seek to better understand the causes of interindividual variability in the ERP responses of older adults and its relation to cognitive performance. PMID

  8. Age-Related Decline in Brain Resources Modulates Genetic Effects on Cognitive Functioning

    PubMed Central

    Lindenberger, Ulman; Nagel, Irene E.; Chicherio, Christian; Li, Shu-Chen; Heekeren, Hauke R.; Bäckman, Lars

    2008-01-01

    Individual differences in cognitive performance increase from early to late adulthood, likely reflecting influences of a multitude of factors. We hypothesize that losses in neurochemical and anatomical brain resources in normal aging modulate the effects of common genetic variations on cognitive functioning. Our hypothesis is based on the assumption that the function relating brain resources to cognition is nonlinear, so that genetic differences exert increasingly large effects on cognition as resources recede from high to medium levels in the course of aging. Direct empirical support for this hypothesis comes from a study by Nagel et al. (2008), who reported that the effects of the Catechol-O-Methyltransferase (COMT) gene on cognitive performance are magnified in old age and interacted with the Brain-Derived Neurotrophic Factor (BDNF) gene. We conclude that common genetic polymorphisms contribute to the increasing heterogeneity of cognitive functioning in old age. Extensions of the hypothesis to other polymorphisms are discussed. (150 of 150 words) PMID:19225597

  9. Age-related changes in neuromuscular function of the quadriceps muscle in physically active adults.

    PubMed

    Mau-Moeller, Anett; Behrens, Martin; Lindner, Tobias; Bader, Rainer; Bruhn, Sven

    2013-06-01

    Substantial evidence exists for the age-related decline in maximal strength and strength development. Despite the importance of knee extensor strength for physical function and mobility in the elderly, studies focusing on the underlying neuromuscular mechanisms of the quadriceps muscle weakness are limited. The aim of this study was to investigate the contributions of age-related neural and muscular changes in the quadriceps muscle to decreases in isometric maximal voluntary torque (iMVT) and explosive voluntary strength. The interpolated twitch technique and normalized surface electromyography (EMG) signal during iMVT were analyzed to assess changes in neural drive to the muscles of 15 young and 15 elderly volunteers. The maximal rate of torque development as well as rate of torque development, impulse and neuromuscular activation in the early phase of contraction were determined. Spinal excitability was estimated using the H reflex technique. Changes at the muscle level were evaluated by analyzing the contractile properties and lean mass. The age-related decrease in iMVT was accompanied by a decline in voluntary activation and normalized surface EMG amplitude. Mechanical parameters of explosive voluntary strength were reduced while the corresponding muscle activation remained primarily unchanged. The spinal excitability of the vastus medialis was not different while M wave latency was longer. Contractile properties and lean mass were reduced. In conclusion, the age-related decline in iMVT of the quadriceps muscle might be due to a reduced neural drive and changes in skeletal muscle properties. The decrease in explosive voluntary strength seemed to be more affected by muscular than by neural changes. PMID:23453325

  10. Functional correlates of brain aging: beta and gamma frequency band responses to age-related cortical changes.

    PubMed

    Christov, Mario; Dushanova, Juliana

    2016-01-01

    The brain as a system with gradually declined resources by age maximizes its performance by neural network reorganization for greater efficiency of neuronal oscillations in a given frequency band. Whether event-related high-frequency band responses are related to plasticity in neural recruitment contributed to the stability of sensory/cognitive mechanisms accompanying aging or are underlined pathological changes seen in aging brain remains unknown. Aged effect on brain electrical activity was studied in auditory discrimination task (low-frequency and high-frequency tone) at particular cortical locations in beta (β1: 12.5-20; β2: 20.5-30 Hz) and gamma frequency bands (γ1: 30.5-49; γ2: 52-69 Hz) during sensory (post-stimulus interval 0-250 ms) and cognitive processing (250-600 ms). Beta1 activity less affected by age during sensory processing. Reduced beta1 activity was more widespread during cognitive processing. This difference increased in fronto-parietal direction more expressed after high-frequency tone stimulation. Beta2 and gamma activity were more pronounced with progressive age during sensory processing. Reducing regional-process specificity with progressing age characterized age-related and tone-dependent beta2 changes during sensory, but not during cognitive processing. Beta2 and gamma activity diminished with age on cognitive processes, except the higher frontal tone-dependent gamma activity during cognitive processing. With increasing age, larger gamma2 activity was more expressed over the frontal brain areas to high tone discrimination and hand reaction choice. These gamma2 differences were shifted from posterior to anterior brain regions with advancing age. The aged influence was higher on cognitive processes than on perceptual ones. PMID:27373947

  11. Age-related changes in reservoir and excess components of central aortic pressure in asymptomatic adults.

    PubMed

    Bia, Daniel; Cymberknop, Leandro; Zócalo, Yanina; Farro, Ignacio; Torrado, Juan; Farro, Federico; Pessana, Franco; Armentano, Ricardo L

    2011-01-01

    Study of humans aging has presented difficulties in separating the aging process from concomitant disease and/or in defining normality and abnormality during its development. In accordance with this, aging associates structural and functional changes evidenced in variations in vascular parameters witch suffer alterations during atherosclerosis and have been proposed as early markers of the disease. The absence of adequate tools to differentiate the expected (normal) vascular changes due to aging from those related with a vascular disease is not a minor issue. For an individual, an early diagnosis of a vascular disease should be as important as the diagnosis of a healthy vascular aging. Recent studies have proposed that the capacitive or reservoir function of the aorta and large elastic arteries plays a major role in determining the pulse wave morphology. The arterial pressure waveform can be explained in terms of a reservoir pressure, related to the arterial system compliance, and an "excess" or wave-related pressure, associated with the traveling waves. The aim of this study was to evaluate, by means of a mathematical approach, age-related changes in measured, reservoir and excess central aortic pressure in order to determine if age-related changes are concentrated in particular decades of life. Central aortic pressure waveform was non-invasively obtained in healthy subjects (age range: 20-69 years old). Age-related profiles in measured, reservoir and excess pressure were calculated.

  12. Beneficial effects of multisensory and cognitive stimulation on age-related cognitive decline in long-term-care institutions

    PubMed Central

    De Oliveira, Thaís Cristina Galdino; Soares, Fernanda Cabral; De Macedo, Liliane Dias E Dias; Diniz, Domingos Luiz Wanderley Picanço; Bento-Torres, Natáli Valim Oliver; Picanço-Diniz, Cristovam Wanderley

    2014-01-01

    The aim of the present report was to evaluate the effectiveness and impact of multisensory and cognitive stimulation on improving cognition in elderly persons living in long-term-care institutions (institutionalized [I]) or in communities with their families (noninstitutionalized [NI]). We compared neuropsychological performance using language and Mini-Mental State Examination (MMSE) test scores before and after 24 and 48 stimulation sessions. The two groups were matched by age and years of schooling. Small groups of ten or fewer volunteers underwent the stimulation program, twice a week, over 6 months (48 sessions in total). Sessions were based on language and memory exercises, as well as visual, olfactory, auditory, and ludic stimulation, including music, singing, and dance. Both groups were assessed at the beginning (before stimulation), in the middle (after 24 sessions), and at the end (after 48 sessions) of the stimulation program. Although the NI group showed higher performance in all tasks in all time windows compared with I subjects, both groups improved their performance after stimulation. In addition, the improvement was significantly higher in the I group than the NI group. Language tests seem to be more efficient than the MMSE to detect early changes in cognitive status. The results suggest the impoverished environment of long-term-care institutions may contribute to lower cognitive scores before stimulation and the higher improvement rate of this group after stimulation. In conclusion, language tests should be routinely adopted in the neuropsychological assessment of elderly subjects, and long-term-care institutions need to include regular sensorimotor, social, and cognitive stimulation as a public health policy for elderly persons. PMID:24600211

  13. Beneficial effects of multisensory and cognitive stimulation on age-related cognitive decline in long-term-care institutions.

    PubMed

    De Oliveira, Thaís Cristina Galdino; Soares, Fernanda Cabral; De Macedo, Liliane Dias E Dias; Diniz, Domingos Luiz Wanderley Picanço; Bento-Torres, Natáli Valim Oliver; Picanço-Diniz, Cristovam Wanderley

    2014-01-01

    The aim of the present report was to evaluate the effectiveness and impact of multisensory and cognitive stimulation on improving cognition in elderly persons living in long-term-care institutions (institutionalized [I]) or in communities with their families (noninstitutionalized [NI]). We compared neuropsychological performance using language and Mini-Mental State Examination (MMSE) test scores before and after 24 and 48 stimulation sessions. The two groups were matched by age and years of schooling. Small groups of ten or fewer volunteers underwent the stimulation program, twice a week, over 6 months (48 sessions in total). Sessions were based on language and memory exercises, as well as visual, olfactory, auditory, and ludic stimulation, including music, singing, and dance. Both groups were assessed at the beginning (before stimulation), in the middle (after 24 sessions), and at the end (after 48 sessions) of the stimulation program. Although the NI group showed higher performance in all tasks in all time windows compared with I subjects, both groups improved their performance after stimulation. In addition, the improvement was significantly higher in the I group than the NI group. Language tests seem to be more efficient than the MMSE to detect early changes in cognitive status. The results suggest the impoverished environment of long-term-care institutions may contribute to lower cognitive scores before stimulation and the higher improvement rate of this group after stimulation. In conclusion, language tests should be routinely adopted in the neuropsychological assessment of elderly subjects, and long-term-care institutions need to include regular sensorimotor, social, and cognitive stimulation as a public health policy for elderly persons. PMID:24600211

  14. Chronic acarbose treatment alleviates age-related behavioral and biochemical changes in SAMP8 mice.

    PubMed

    Tong, Jing-Jing; Chen, Gui-Hai; Wang, Fang; Li, Xue-Wei; Cao, Lei; Sui, Xu; Tao, Fei; Yan, Wen-Wen; Wei, Zhao-Jun

    2015-05-01

    The administration of maintaining the homeostasis of insulin/insulin-like growth factor 1 (IGF-1) signaling and/or glucose metabolism may reverse brain aging. In the present study, we investigated the effect of acarbose, an inhibitor of α-glucosidase, on age-related behavioral and biochemical changes. The SAMP8 mice were randomly divided into old control group and acarbose-treatment group. The mice in the acarbose group were administered acarbose (20 mg/kg/d, dissolved in drinking water) orally from 3 to 9 months of age when a new group of 3-month-old mice was added as young controls. The results showed that the aged controls exhibited declines in sensorimotor ability, open field anxiety, spatial and non-spatial memory abilities, decreased serum insulin levels, increased IGF-1 receptor and synaptotagmin 1 (Syt1) levels and decreased insulin receptor, brain-derived neurotrophic factor (BDNF) and syntaxin 1 (Stx1) levels in the hippocampal layers. The age-related behavioral deficits correlated with the serological and histochemical data. Chronic acarbose treatment relieved these age-related changes, especially with respect to learning and memory abilities. This protective effect of acarbose on age-related behavioral impairments might be related to changes in the insulin system and the levels of BDNF, IGF-1R, and the pre-synaptic proteins Syt1 and Stx1. In conclusion, long-term treatment with acarbose ameliorated the behavioral deficits and biochemical changes in old SAMP8 mice and promoted successful aging. This study provides insight into the potential of acarbose for the treatment of brain aging.

  15. Aging-related changes in respiratory system mechanics and morphometry in mice.

    PubMed

    Elliott, Jonathan E; Mantilla, Carlos B; Pabelick, Christina M; Roden, Anja C; Sieck, Gary C

    2016-07-01

    Previous work investigating respiratory system mechanics in mice has reported an aging-related increase in compliance and mean linear intercept (Lm). However, these changes were assessed using only a young (2-mo-old) and old (20- and 26-mo-old) group yet were interpreted to reflect a linear evolution across the life span. Therefore, to investigate respiratory system mechanics and lung morphometry across a more complete spectrum of ages, we utilized 2 (100% survival, n = 6)-, 6 (100% survival, n = 12)-, 18 (90% survival, n = 12)-, 24 (75% survival, n = 12)-, and 30 (25% survival, n = 12)-mo-old C57BL/6 mice. We found a nonlinear aging-related decrease in respiratory system resistance and increase in dynamic compliance and hysteresis between 2- and 24-mo-old mice. However, in 30-mo-old mice, respiratory system resistance increased, and dynamic compliance and hysteresis decreased relative to 24-mo-old mice. Respiratory system impedance spectra were measured between 1-20.5 Hz at positive end-expiratory pressures (PEEP) of 1, 3, 5, and 7 cmH2O. Respiratory system resistance and reactance at each level of PEEP were increased and decreased, respectively, only in 2-mo-old animals. No differences in the respiratory system impedance spectra were observed in 6-, 18-, 24-, and 30-mo-old mice. Additionally, lungs were fixed following tracheal instillation of 4% paraformaldehyde at 25 cmH2O and processed for Lm and airway collagen deposition. There was an aging-related increase in Lm consistent with emphysematous-like changes and no evidence of increased airway collagen deposition. Accordingly, we demonstrate nonlinear aging-related changes in lung mechanics and morphometry in C57BL/6 mice.

  16. Video games as a means to reduce age-related cognitive decline: attitudes, compliance, and effectiveness.

    PubMed

    Boot, Walter R; Champion, Michael; Blakely, Daniel P; Wright, Timothy; Souders, Dustin J; Charness, Neil

    2013-01-01

    Recent research has demonstrated broad benefits of video game play to perceptual and cognitive abilities. These broad improvements suggest that video game-based cognitive interventions may be ideal to combat the many perceptual and cognitive declines associated with advancing age. Furthermore, game interventions have the potential to induce higher rates of intervention compliance compared to other cognitive interventions as they are assumed to be inherently enjoyable and motivating. We explored these issues in an intervention that tested the ability of an action game and a "brain fitness" game to improve a variety of abilities. Cognitive abilities did not significantly improve, suggesting caution when recommending video game interventions as a means to reduce the effects of cognitive aging. However, the game expected to produce the largest benefit based on previous literature (an action game) induced the lowest intervention compliance. We explain this low compliance by participants' ratings of the action game as less enjoyable and by their prediction that training would have few meaningful benefits. Despite null cognitive results, data provide valuable insights into the types of video games older adults are willing to play and why. PMID:23378841

  17. Video games as a means to reduce age-related cognitive decline: attitudes, compliance, and effectiveness.

    PubMed

    Boot, Walter R; Champion, Michael; Blakely, Daniel P; Wright, Timothy; Souders, Dustin J; Charness, Neil

    2013-01-01

    Recent research has demonstrated broad benefits of video game play to perceptual and cognitive abilities. These broad improvements suggest that video game-based cognitive interventions may be ideal to combat the many perceptual and cognitive declines associated with advancing age. Furthermore, game interventions have the potential to induce higher rates of intervention compliance compared to other cognitive interventions as they are assumed to be inherently enjoyable and motivating. We explored these issues in an intervention that tested the ability of an action game and a "brain fitness" game to improve a variety of abilities. Cognitive abilities did not significantly improve, suggesting caution when recommending video game interventions as a means to reduce the effects of cognitive aging. However, the game expected to produce the largest benefit based on previous literature (an action game) induced the lowest intervention compliance. We explain this low compliance by participants' ratings of the action game as less enjoyable and by their prediction that training would have few meaningful benefits. Despite null cognitive results, data provide valuable insights into the types of video games older adults are willing to play and why.

  18. Video Games as a Means to Reduce Age-Related Cognitive Decline: Attitudes, Compliance, and Effectiveness

    PubMed Central

    Boot, Walter R.; Champion, Michael; Blakely, Daniel P.; Wright, Timothy; Souders, Dustin J.; Charness, Neil

    2013-01-01

    Recent research has demonstrated broad benefits of video game play to perceptual and cognitive abilities. These broad improvements suggest that video game-based cognitive interventions may be ideal to combat the many perceptual and cognitive declines associated with advancing age. Furthermore, game interventions have the potential to induce higher rates of intervention compliance compared to other cognitive interventions as they are assumed to be inherently enjoyable and motivating. We explored these issues in an intervention that tested the ability of an action game and a “brain fitness” game to improve a variety of abilities. Cognitive abilities did not significantly improve, suggesting caution when recommending video game interventions as a means to reduce the effects of cognitive aging. However, the game expected to produce the largest benefit based on previous literature (an action game) induced the lowest intervention compliance. We explain this low compliance by participants’ ratings of the action game as less enjoyable and by their prediction that training would have few meaningful benefits. Despite null cognitive results, data provide valuable insights into the types of video games older adults are willing to play and why. PMID:23378841

  19. Age-related changes in the topological organization of the white matter structural connectome across the human lifespan.

    PubMed

    Zhao, Tengda; Cao, Miao; Niu, Haijing; Zuo, Xi-Nian; Evans, Alan; He, Yong; Dong, Qi; Shu, Ni

    2015-10-01

    Lifespan is a dynamic process with remarkable changes in brain structure and function. Previous neuroimaging studies have indicated age-related microstructural changes in specific white matter tracts during development and aging. However, the age-related alterations in the topological architecture of the white matter structural connectome across the human lifespan remain largely unknown. Here, a cohort of 113 healthy individuals (ages 9-85) with both diffusion and structural MRI acquisitions were examined. For each participant, the high-resolution white matter structural networks were constructed by deterministic fiber tractography among 1024 parcellation units and were quantified with graph theoretical analyses. The global network properties, including network strength, cost, topological efficiency, and robustness, followed an inverted U-shaped trajectory with a peak age around the third decade. The brain areas with the most significantly nonlinear changes were located in the prefrontal and temporal cortices. Different brain regions exhibited heterogeneous trajectories: the posterior cingulate and lateral temporal cortices displayed prolonged maturation/degeneration compared with the prefrontal cortices. Rich-club organization was evident across the lifespan, whereas hub integration decreased linearly with age, especially accompanied by the loss of frontal hubs and their connections. Additionally, age-related changes in structural connections were predominantly located within and between the prefrontal and temporal modules. Finally, based on the graph metrics of structural connectome, accurate predictions of individual age were obtained (r = 0.77). Together, the data indicated a dynamic topological organization of the brain structural connectome across human lifespan, which may provide possible structural substrates underlying functional and cognitive changes with age.

  20. Age-related structural and functional changes in the cochlear nucleus.

    PubMed

    Frisina, Robert D; Walton, Joseph P

    2006-01-01

    Presbycusis - age-related hearing loss - is a key communication disorder and chronic medical condition of our aged population. The cochlear nucleus is the major site of projections from the auditory portion of the inner ear. Relative to other levels of the peripheral and central auditory systems, relatively few studies have been conducted examining age-related changes in the cochlear nucleus. The neurophysiological investigations suggest declines in glycine-mediated inhibition, reflected in increased firing rates in cochlear nucleus neurons from old animals relative to young adults. Biochemical investigations of glycine inhibition in the cochlear nucleus are consistent with the functional aging declines of this inhibitory neurotransmitter system that affect complex sound processing. Anatomical reductions in neurons of the cochlear nucleus and their output pathways can occur due to aging changes in the brain, as well as due to age-dependent plasticity of the cochlear nucleus in response to the age-related loss of inputs from the cochlea, particularly from the basal, high-frequency regions. Novel preventative and curative biomedical interventions in the future aimed at alleviating the hearing loss that comes with age, will likely emanate from increasing our knowledge and understanding of its neural and molecular bases. To the extent that this sensory deficit resides in the central auditory system, including the cochlear nucleus, future neural therapies will be able to improve hearing in the elderly.

  1. Age-Related Changes of Adaptive and Neuropsychological Features in Persons with Down Syndrome

    PubMed Central

    Ghezzo, Alessandro; Salvioli, Stefano; Solimando, Maria Caterina; Palmieri, Alice; Chiostergi, Chiara; Scurti, Maria; Lomartire, Laura; Bedetti, Federica; Cocchi, Guido; Follo, Daniela; Pipitone, Emanuela; Rovatti, Paolo; Zamberletti, Jessica; Gomiero, Tiziano; Castellani, Gastone; Franceschi, Claudio

    2014-01-01

    Down Syndrome (DS) is characterised by premature aging and an accelerated decline of cognitive functions in the vast majority of cases. As the life expectancy of DS persons is rapidly increasing, this decline is becoming a dramatic health problem. The aim of this study was to thoroughly evaluate a group of 67 non-demented persons with DS of different ages (11 to 66 years), from a neuropsychological, neuropsychiatric and psychomotor point of view in order to evaluate in a cross-sectional study the age-related adaptive and neuropsychological features, and to possibly identify early signs predictive of cognitive decline. The main finding of this study is that both neuropsychological functions and adaptive skills are lower in adult DS persons over 40 years old, compared to younger ones. In particular, language and short memory skills, frontal lobe functions, visuo-spatial abilities and adaptive behaviour appear to be the more affected domains. A growing deficit in verbal comprehension, along with social isolation, loss of interest and greater fatigue in daily tasks, are the main features found in older, non demented DS persons evaluated in our study. It is proposed that these signs can be alarm bells for incipient dementia, and that neuro-cognitive rehabilitation and psycho-pharmacological interventions must start as soon as the fourth decade (or even earlier) in DS persons, i.e. at an age where interventions can have the greatest efficacy. PMID:25419980

  2. Superoxide Dismutase 1 Loss Disturbs Intracellular Redox Signaling, Resulting in Global Age-Related Pathological Changes

    PubMed Central

    2014-01-01

    Aging is characterized by increased oxidative stress, chronic inflammation, and organ dysfunction, which occur in a progressive and irreversible manner. Superoxide dismutase (SOD) serves as a major antioxidant and neutralizes superoxide radicals throughout the body. In vivo studies have demonstrated that copper/zinc superoxide dismutase-deficient (Sod1−/−) mice show various aging-like pathologies, accompanied by augmentation of oxidative damage in organs. We found that antioxidant treatment significantly attenuated the age-related tissue changes and oxidative damage-associated p53 upregulation in Sod1−/− mice. This review will focus on various age-related pathologies caused by the loss of Sod1 and will discuss the molecular mechanisms underlying the pathogenesis in Sod1−/− mice. PMID:25276767

  3. Investigating age-related changes in anterior and posterior neural activity throughout the information processing stream.

    PubMed

    Alperin, Brittany R; Tusch, Erich S; Mott, Katherine K; Holcomb, Phillip J; Daffner, Kirk R

    2015-10-01

    Event-related potential (ERP) and other functional imaging studies often demonstrate age-related increases in anterior neural activity and decreases in posterior activity while subjects carry out task demands. It remains unclear whether this "anterior shift" is limited to late cognitive operations like those indexed by the P3 component, or is evident during other stages of information processing. The temporal resolution of ERPs provided an opportunity to address this issue. Temporospatial principal component analysis (PCA) was used to identify underlying components that may be obscured by overlapping ERP waveforms. ERPs were measured during a visual oddball task in 26 young, 26 middle-aged, and 29 old subjects who were well-matched for IQ, executive function, education, and task performance. PCA identified six anterior factors peaking between ∼140 ms and 810 ms, and four posterior factors peaking between ∼300 ms and 810 ms. There was an age-related increase in the amplitude of anterior factors between ∼200 and 500 ms, and an age-associated decrease in amplitude of posterior factors after ∼500 ms. The increase in anterior processing began as early as middle-age, was sustained throughout old age, and appeared to be linear in nature. These results suggest that age-associated increases in anterior activity occur after early sensory processing has taken place, and are most prominent during a period in which attention is being marshaled to evaluate a stimulus. In contrast, age-related decreases in posterior activity manifest during operations involved in stimulus categorization, post-decision monitoring, and preparation for an upcoming event. PMID:26295684

  4. Age-related changes in conventional road versus off-road triathlon performance.

    PubMed

    Lepers, Romuald; Stapley, Paul J

    2011-08-01

    The aims of this study were: (i) to analyze age-related declines in swimming, cycling, and running performances for road-based and off-road triathlons, and (ii) to compare age-related changes in these three disciplines between road-based and off-road triathlons. Swimming, cycling, running and total time performances of the top five males between 20 and 70 years of age (in 5-year intervals) were analyzed for short distance road-based (1.5 km swim, 40 km cycle, and 10 km run) and off-road (1.5 km swim, 30 km mountain bike, and 11 km trail run) triathlons at the 2009 World Championships. Independently of age, there was a lesser age-related decline in cycling performance (P < 0.01) compared to running and swimming for road-based triathlon. In contrast, age-related decline did not differ between the three locomotion modes for off-road triathlon. With advancing age, the performance decline was less pronounced (P < 0.01) for road-based than for off-road triathlon in swimming (≥65 years), cycling (≥50 years), running (≥60 years), and total event (≥55 years) times, respectively. These results suggest that the rate of the decline in performance for off-road triathlon is greater than for road-based triathlon, indicating that the type of discipline (road vs. mountain bike cycling and road vs. trail running) exerts an important influence on the magnitude of the age-associated changes in triathlon performance.

  5. Age-related structural and functional changes of low back muscles.

    PubMed

    Hiepe, Patrick; Gussew, Alexander; Rzanny, Reinhard; Kurz, Eduard; Anders, Christoph; Walther, Mario; Scholle, Hans-Christoph; Reichenbach, Jürgen R

    2015-05-01

    During aging declining maximum force capacity with more or less unchanged fatigability is observed with the underlying mechanisms still not fully understood. Therefore, we compared morphology and function of skeletal muscles between different age groups. Changes in high-energy phosphate turnover (PCr, Pi and pH) and muscle functional MRI (mfMRI) parameters, including proton transverse relaxation time (T2), diffusion (D) and vascular volume fraction (f), were investigated in moderately exercised low back muscles of young and late-middle-aged healthy subjects with (31)P-MR spectroscopy, T2- and diffusion-weighted MRI at 3T. In addition, T1-weighted MRI data were acquired to determine muscle cross-sectional areas (CSA) and to assess fat infiltration into muscle tissue. Except for pH, both age groups showed similar load-induced MR changes and rates of perceived exertion (RPE), which indicates comparable behavior of muscle activation at moderate loads. Changes of mfMRI parameters were significantly associated with RPE in both cohorts. Age-related differences were observed, with lower pH and higher Pi/ATP ratios as well as lower D and f values in the late-middle-aged subjects. These findings are ascribed to age-related changes of fiber type composition, fiber size and vascularity. Interestingly, post exercise f was negatively associated with fat infiltration with the latter being significantly higher in late-middle-aged subjects. CSA of low back muscles remained unchanged, while CSA of inner back muscle as well as mean T2 at rest were associated with maximum force capacity. Overall, applying the proposed MR approach provides evidence of age-related changes in several muscle tissue characteristics and gives new insights into the physiological processes that take place during aging.

  6. Age-related changes in the thickness of cortical zones in humans.

    PubMed

    McGinnis, Scott M; Brickhouse, Michael; Pascual, Belen; Dickerson, Bradford C

    2011-10-01

    Structural neuroimaging studies have demonstrated that all regions of the cortex are not affected equally by aging, with frontal regions appearing especially susceptible to atrophy. The "last in, first out" hypothesis posits that aging is, in a sense, the inverse of development: late-maturing regions of the brain are preferentially vulnerable to age-related loss of structural integrity. We tested this hypothesis by analyzing age-related changes in regional cortical thickness via three methods: (1) an exploratory linear regression of cortical thickness and age across the entire cortical mantle (2) an analysis of age-related differences in the thickness of zones of cortex defined by functional/cytoarchitectural affiliation (including primary sensory/motor, unimodal association, heteromodal association, and paralimbic zones), and (3) an analysis of age-related differences in the thickness of regions of cortex defined by surface area expansion in the period between birth and early adulthood. Subjects were grouped as young (aged 18-29, n = 138), middle-aged (aged 30-59, n = 80), young-old (aged 60-79, n = 60), and old-old (aged 80+, n = 38). Thinning of the cortex between young and middle-aged adults was greatest in heteromodal association cortex and regions of high postnatal surface area expansion. In contrast, thinning in old-old age was greatest in primary sensory/motor cortices and regions of low postnatal surface area expansion. In sum, these results lead us to propose a sequential "developmental-sensory" model of aging, in which developmental factors influence cortical vulnerability relatively early in the aging process, whereas later-in more advanced stages of aging-factors specific to primary sensory and motor cortices confer vulnerability. This model offers explicitly testable hypotheses and suggests the possibility that normal aging may potentially allow for multiple opportunities for intervention to promote the structural integrity of the cerebral

  7. Formaldehyde as a trigger for protein aggregation and potential target for mitigation of age-related, progressive cognitive impairment.

    PubMed

    Su, Tao; Monte, Woodrow C; Hu, Xintian; He, Yingge; He, Rongqiao

    2016-01-01

    Recently, formaldehyde (FA), existing in a number of different cells including neural cells, was found to affect age-related cognitive impairment. Oral administration of methanol (the metabolic precursor of FA) triggers formation of senile plaques (SPs) and Tau hyperphosphorylation in the brains of monkeys with memory decline. Intraperitoneal injection of FA leads to hyperphosphorylation of Tau in wild-type mouse brains and N2a cells through activation of glycogen synthase kinase-3β (GSK-3β). Furthermore, formaldehyde at low concentrations can directly induce Tau aggregation and amyloid β (Aβ) peptide deposits in vitro. Formaldehyde-induced Tau aggregation is implicated in cytotoxicity and neural cell apoptosis. Clarifying how FA triggers Aβ deposits and Tau hyperphosphorlyation will not only improve our understanding of the molecular and cellular mechanisms of age-related cognitive impairment but will also contribute to the ongoing investigation of alternate targets for new drugs. Here, we review the role of FA, particularly that of endogenous origin, in protein aggregation and as a potential drug intervention in the development of agerelated cognitive impairment.

  8. ERBB4 Polymorphism and Family History of Psychiatric Disorders on Age-Related Cortical Changes in Healthy Children

    PubMed Central

    Douet, Vanessa; Chang, Linda; Lee, Kristin; Ernst, Thomas

    2015-01-01

    Background Genetic variations in ERBB4 were associated with increased susceptibility for schizophrenia (SCZ) and bipolar disorders (BPD). Structural imaging studies showed cortical abnormalities in adolescents and adults with SCZ or BPD. However, less is known about subclinical cortical changes or the influence of ERBB4 on cortical development. Methods 971 healthy children (ages 3–20 years old; 462 girls and 509 boys) were genotyped for the ERBB4-rs7598440 variants, had structural MRI, and cognitive evaluation (NIH Toolbox ®). We investigated the effects of ERBB4 variants and family history of SCZ and/or BPD (FH) on cortical measures and cognitive performances across ages 3–20 years using a general additive model. Results Variations in ERBB4 and FH impact differentially the age-related cortical changes in regions often affected by SCZ and BPD. The ERBB4-TT-risk genotype children with no FH had subtle cortical changes across the age span, primarily located in the left temporal lobe and superior parietal cortex. In contrast, the TT-risk genotype children with FH had more pronounced age-related changes, mainly in the frontal lobes compared to the non-risk genotype children. Interactive effects of age, FH and ERBB4 variations were also found on episodic memory and working memory, which are often impaired in SCZ and BPD. Conclusions Healthy children carrying the risk-genotype in ERBB4 and/or with FH had cortical measures resembling those reported in SCZ or BPD. These subclinical cortical variations may provide early indicators for increased risk of psychiatric disorders and improve our understanding of the effect of the NRG1–ERBB4 pathway on brain development. PMID:25744101

  9. Age-related decline in verbal learning is moderated by demographic factors, working memory capacity, and presence of amnestic mild cognitive impairment.

    PubMed

    Constantinidou, Fofi; Zaganas, Ioannis; Papastefanakis, Emmanouil; Kasselimis, Dimitrios; Nidos, Andreas; Simos, Panagiotis G

    2014-09-01

    Age-related memory changes are highly varied and heterogeneous. The study examined the rate of decline in verbal episodic memory as a function of education level, auditory attention span and verbal working memory capacity, and diagnosis of amnestic mild cognitive impairment (a-MCI). Data were available on a community sample of 653 adults aged 17-86 years and 70 patients with a-MCI recruited from eight broad geographic areas in Greece and Cyprus. Measures of auditory attention span and working memory capacity (digits forward and backward) and verbal episodic memory (Auditory Verbal Learning Test [AVLT]) were used. Moderated mediation regressions on data from the community sample did not reveal significant effects of education level on the rate of age-related decline in AVLT indices. The presence of a-MCI was a significant moderator of the direct effect of Age on both immediate and delayed episodic memory indices. The rate of age-related decline in verbal episodic memory is normally mediated by working memory capacity. Moreover, in persons who display poor episodic memory capacity (a-MCI group), age-related memory decline is expected to advance more rapidly for those who also display relatively poor verbal working memory capacity.

  10. Age-related cognitive impairments in mice with a conditional ablation of the neural cell adhesion molecule.

    PubMed

    Bisaz, Reto; Boadas-Vaello, Pere; Genoux, David; Sandi, Carmen

    2013-04-01

    Most of the mechanisms involved in neural plasticity support cognition, and aging has a considerable effect on some of these processes. The neural cell adhesion molecule (NCAM) of the immunoglobulin superfamily plays a pivotal role in structural and functional plasticity and is required to modulate cognitive and emotional behaviors. However, whether aging is associated with NCAM alterations that might contribute to age-related cognitive decline is not currently known. In this study, we determined whether conditional NCAM-deficient mice display increased vulnerability to age-related cognitive and emotional alterations. We assessed the NCAM expression levels in the hippocampus and medial prefrontal cortex (mPFC) and characterized the performance of adult and aged conditional NCAM-deficient mice and their age-matched wild-type littermates in a delayed matching-to-place test in the Morris water maze and a delayed reinforced alternation test in the T-maze. Although aging in wild-type mice is associated with an isoform-specific reduction of NCAM expression levels in the hippocampus and mPFC, these mice exhibited only mild impairments in working/episodic-like memory performance. However, aged conditional NCAM-deficient mice displayed pronounced impairments in both the delayed matching-to-place and the delayed reinforced alternation tests. Importantly, the deficits of aged NCAM-deficient mice in these working/episodic-like memory tasks could not be attributed to increased anxiety-like behaviors or to differences in locomotor activity. Taken together, these data indicate that reduced NCAM expression in the forebrain might be a critical factor for the occurrence of cognitive impairments during aging.

  11. Age-related morphological changes in lid margin and meibomian gland anatomy.

    PubMed

    Hykin, P G; Bron, A J

    1992-07-01

    Meibomian gland dysfunction (MGD) is responsible for recurrent irritative symptoms. Attempts to characterize MGD have largely concentrated on microbial and lipid abnormalities in meibomian gland secretions. Few reports describe histological abnormalities in this disease, and fewer still morphological changes. This article follows a previous study that established a classification for MGD. This was based on morphological changes in the meibomian gland and lid margin. Using this classification, we studied the age-related changes in 80 subjects, between 5 and 87 years of age without ocular disease. The lid margin became thicker after childhood. Lid margin vascularity and cutaneous hyperkeratinization increased with age in both lids, whereas, telangiectasia increased with age in the lower lid and squamous blepharitis and posterior lid margin rounding were more common after 50 years of age in the upper lid. Multiple rows of meibomian gland orifices occurred more frequently in the upper than lower lid, and orifice narrowing and pouting increased with age. No age-related changes in the shape or form of the mucocutaneous function, gland ducts, or acini were found. Meibomian gland secretions were less easily expressed in the elderly. We have attempted to define a normal range of lid morphology in healthy children and adults that we believe to be important for the subsequent definition of lid disease, and in particular, posterior blepharitis.

  12. Mechanism of age-related changes of bone marrow mesenchymal stem cells in senile osteoporosis.

    PubMed

    Huang, C; Zhang, G F; Han, J; Liao, G J; Zou, B G

    2016-01-01

    This study was carried out to explore the age-related changes of bone marrow mesenchymal stem cells (BMMSCs) in mice as well as the influence of autophagy on the age-related changes of BMMSCs. BMMSCs aging-associated protein acetylation P53, P21 and P16 expressions in young and senile mice, protein expression of telomerase reverse transcriptase (TERT) as well as reactive oxygen species (ROS) level were detected and compared; the expression of BMMSCs autophagy associated gene, autophagy related protein molecule and LC3 molecule were detected; the influence of differently concentrated rapamycin and 3-MA on BMMSCs autophagy level was observed to select effective concentrations; the influence of rapamycin and 3-MA on BMMSCs cell cycle-related gene expression, apoptosis related gene expression and ROS level were discussed. Results revealed that the senile BMMSCs group had higher acetylation P53, P21 and P16 expression and fluorescence intensity than the young group, but its TERT expression, Beclin1 and LC3 gene expression and fluorescence intensity were lower than the young group. Both rapamycin and 3-MA inhibited CyclinD1 (CCND1) and CyclinD2 (CCND2) expression. Rapamycin promoted the expression of apoptosis-related genes Caspase3 and Caspase8 in the senile group, while 3-MA inhibited them in both the young and senile groups. It can therefore be concluded that senile BMMSCs have multiple age-related changes, performing as decrease of osteogenic capability and multiplication capacity, increase of acetylation P53, P21 and P16 protein expression, apoptosis and ROS level as well as decrease of telomerase activity. Furthermore, the autophagy level in senile BMMSCs reduced compared with young cells; autophagy activation can decrease ROS level and autophagy suppression improves ROS level; and autophagy regulation affects cell cycle and apoptosis. PMID:27358149

  13. Genetics of ageing-related changes in brain white matter integrity - a review.

    PubMed

    Kanchibhotla, Sri C; Mather, Karen A; Wen, Wei; Schofield, Peter R; Kwok, John B J; Sachdev, Perminder S

    2013-01-01

    White matter (WM) plays a vital role in the efficient transfer of information between grey matter regions. Modern imaging techniques such as diffusion tensor imaging (DTI) have enabled the examination of WM microstructural changes across the lifespan, but there is limited knowledge about the role genetics plays in the pattern and aetiology of age-related WM microstructural changes. Family and twin studies suggest that the heritability of WM integrity measures changes over the lifespan, with the common DTI measure, fractional anisotropy (FA), showing moderate to high heritability in adults. However, few heritability studies have been undertaken in older adults. Linkage studies in middle-aged adults suggest that specific regions on chromosomes 3 and 15 may harbour genetic variants for WM integrity. A number of studies have investigated candidate genes, with the APOE ɛ4 polymorphism being the most frequently studied. Although these candidate gene studies suggest associations of particular genes with WM integrity measures in some specific brain regions, the findings remain inconsistent due to differences in their methodologies, samples and the outcome measures used. The APOE ɛ4 allele has been associated with decreased WM integrity (FA) in the cingulum, corpus callosum and parahippocampal gyrus. Only one genome-wide association study of global WM integrity measures in older adults has been published, and reported suggestive single nucleotide polymorphisms await replication. Overall, genetic age-related WM integrity studies are lacking and a concerted effort to examine the genetic determinants of age-related decline in WM integrity is clearly needed to improve our understanding of the ageing brain.

  14. Age-related changes in the transcriptome of antibody-secreting cells

    PubMed Central

    Kurupati, Raj; Showe, Louise C.; Ertl, Hildegund C.J.

    2016-01-01

    We analyzed age-related defects in B cell populations from young and aged mice. Microarray analysis of bone marrow resident antibody secreting cells (ASCs) showed significant changes upon aging, affecting multiple genes, pathways and functions including those that play a role in immune regulation, humoral immune responses, chromatin structure and assembly, cell metabolism and the endoplasmic reticulum (ER) stress response. Further analysis showed upon aging defects in energy production through glucose catabolism with reduced oxidative phosphorylation. In addition aged B cells had increased levels of reactive oxygen-species (ROS), which was linked to enhanced expression of the co-inhibitor programmed cell death (PD)-1. PMID:26967249

  15. Age-related changes in endothelial permeability and distribution volume of albumin in rat aorta.

    PubMed

    Belmin, J; Corman, B; Merval, R; Tedgui, A

    1993-03-01

    Age-related changes in macromolecular transport across the arterial wall were investigated in 10-, 20-, and 30-mo-old WAG/Rij rats. Animals were injected with 125I- and 131I-labeled albumin, 90 and 5 min before they were killed, respectively. The transmural distribution of relative concentration of tracers in the aortic wall was obtained using en face serial sectioning technique. The apparent endothelial permeability to albumin calculated from the distribution of 5-min 131I-labeled albumin concentrations was significantly enhanced in 20- and 30-mo-old rats compared with 10-mo-old rats. The apparent distribution volume of albumin within the media, estimated as the mean medial 125I-labeled albumin concentration, was not significantly changed in 20-mo-old rats but was significantly decreased in the 30-mo-old animals. These age-related changes in the macromolecular transport suggest that the entry of plasma macromolecules in the aged arterial wall might be enhanced, whereas the efflux through the media may be impeded, possibly contributing to their trapping in the subendothelium. PMID:8456970

  16. Age-related changes in processing faces from detection to identification: ERP evidence

    PubMed Central

    Daniel, Sharon; Bentin, Shlomo

    2010-01-01

    We examined the ability of people 70 to 90 years old to apply global, configural and featural face-processing strategies. In addition we investigated age-related changes in the ability to categorize faces at basic, subordinate and individual levels. Using the N170 potential as index of early face processing and the P300 component as index of categorical decision making and effort, we found significant age-related perceptual changes which slowed and somewhat impaired face processing. Specifically, older participants had problems integrating face features into global structures, demonstrating enhanced dependence on distal global information. They did not apply configural computations by default while processing faces which suggests that, unless identification is required, they process faces only at a basic level. These perceptual changes could be the cause for slower and less accurate subordinate categorization, particularly when it is based on details. At the neural levels face processing was not right-lateralized, reflecting excessive involvement of the left hemisphere in perception leading to a more general reduction of inter-hemispheric asymmetry. In addition we found excessive but nonselective activation of frontal regions adding support to the view that executive control and particularly inhibition of irrelevant input are reduced in the elderly. PMID:20961658

  17. Age-Related Neurochemical Changes in the Rhesus Macaque Superior Olivary Complex

    PubMed Central

    Gray, Daniel T.; Engle, James R.; Recanzone, Gregg H.

    2014-01-01

    Positive immunoreactivity to the calcium-binding protein parvalbumin (PV) and nitric oxide synthase NADPH-diaphorase (NADPHd) is well documented within neurons of the central auditory system of both rodents and primates. These proteins are thought to play roles in the regulation of auditory processing. Studies examining the age-related changes in expression of these proteins have been conducted primarily in rodents but are sparse in primate models. In the brainstem, the superior olivary complex (SOC) is crucial for the computation of sound source localization in azimuth, and one hallmark of age-related hearing deficits is a reduced ability to localize sounds. To investigate how these histochemical markers change as a function of age and hearing loss, we studied eight rhesus macaques ranging in age from 12 to 35 years. Auditory brainstem responses (ABRs) were obtained in anesthetized animals for click and tone stimuli. The brainstems of these same animals were then stained for PV and NADPHd reactivity. Reactive neurons in the three nuclei of the SOC were counted, and the densities of each cell type were calculated. We found that PV and NADPHd expression increased with both age and ABR thresholds in the medial superior olive but not in either the medial nucleus of the trapezoid body or the lateral superior olive. Together these results suggest that the changes in protein expression employed by the SOC may compensate for the loss of efficacy of auditory sensitivity in the aged primate. PMID:25232570

  18. Age Related Changes in Metabolite Concentrations in the Normal Spinal Cord

    PubMed Central

    Abdel-Aziz, Khaled; Solanky, Bhavana S.; Yiannakas, Marios C.; Altmann, Daniel R.; Wheeler-Kingshott, Claudia A. M.; Thompson, Alan J.; Ciccarelli, Olga

    2014-01-01

    Magnetic resonance spectroscopy (MRS) studies have previously described metabolite changes associated with aging of the healthy brain and provided insights into normal brain aging that can assist us in differentiating age-related changes from those associated with neurological disease. The present study investigates whether age-related changes in metabolite concentrations occur in the healthy cervical spinal cord. 25 healthy volunteers, aged 23–65 years, underwent conventional imaging and single-voxel MRS of the upper cervical cord using an optimised point resolved spectroscopy sequence on a 3T Achieva system. Metabolite concentrations normalised to unsuppressed water were quantified using LCModel and associations between age and spinal cord metabolite concentrations were examined using multiple regressions. A linear decline in total N-Acetyl-aspartate concentration (0.049 mmol/L lower per additional year of age, p = 0.010) and Glutamate-Glutamine concentration (0.054 mmol/L lower per additional year of age, p = 0.002) was seen within our sample age range, starting in the early twenties. The findings suggest that neuroaxonal loss and/or metabolic neuronal dysfunction, and decline in glutamate-glutamine neurotransmitter pool progress with aging. PMID:25310093

  19. Age-related changes in the fracture resistance of male Fischer F344 rat bone.

    PubMed

    Uppuganti, Sasidhar; Granke, Mathilde; Makowski, Alexander J; Does, Mark D; Nyman, Jeffry S

    2016-02-01

    In addition to the loss in bone volume that occurs with age, there is a decline in material properties. To test new therapies or diagnostic tools that target such properties as material strength and toughness, a pre-clinical model of aging would be useful in which changes in bone are similar to those that occur with aging in humans. Toward that end, we hypothesized that similar to human bone, the estimated toughness and material strength of cortical bone at the apparent-level decreases with age in the male Fischer F344 rat. In addition, we tested whether the known decline in trabecular architecture in rats translated to an age-related decrease in vertebra (VB) strength and whether non-X-ray techniques could quantify tissue changes at micron and sub-micron length scales. Bones were harvested from 6-, 12-, and 24-month (mo.) old rats (n=12 per age). Despite a loss in trabecular bone with age, VB compressive strength was similar among the age groups. Similarly, whole-bone strength (peak force) in bending was maintained (femur) or increased (radius) with aging. There was though an age-related decrease in post-yield toughness (radius) and bending strength (femur). The ability to resist crack initiation was actually higher for the 12-mo. and 24-mo. than for 6-mo. rats (notch femur), but the estimated work to propagate the crack was less for the aged bone. For the femur diaphysis region, porosity increased while bound water decreased with age. For the radius diaphysis, there was an age-related increase in non-enzymatic and mature enzymatic collagen crosslinks. Raman spectroscopy analysis of embedded cross-sections of the tibia mid-shaft detected an increase in carbonate subsitution with advanced aging for both inner and outer tissue.

  20. Age-Related Changes of Myelin Basic Protein in Mouse and Human Auditory Nerve

    PubMed Central

    Xing, Yazhi; Samuvel, Devadoss J.; Stevens, Shawn M.; Dubno, Judy R.; Schulte, Bradley A.; Lang, Hainan

    2012-01-01

    Age-related hearing loss (presbyacusis) is the most common type of hearing impairment. One of the most consistent pathological changes seen in presbyacusis is the loss of spiral ganglion neurons (SGNs). Defining the cellular and molecular basis of SGN degeneration in the human inner ear is critical to gaining a better understanding of the pathophysiology of presbyacusis. However, information on age-related cellular and molecular alterations in the human spiral ganglion remains scant, owing to the very limited availably of human specimens suitable for high resolution morphological and molecular analysis. This study aimed at defining age-related alterations in the auditory nerve in human temporal bones and determining if immunostaining for myelin basic protein (MBP) can be used as an alternative approach to electron microscopy for evaluating myelin degeneration. For comparative purposes, we evaluated ultrastructural alternations and changes in MBP immunostaining in aging CBA/CaJ mice. We then examined 13 temporal bones from 10 human donors, including 4 adults aged 38–46 years (middle-aged group) and 6 adults aged 63–91 years (older group). Similar to the mouse, intense immunostaining of MBP was present throughout the auditory nerve of the middle-aged human donors. Significant declines in MBP immunoreactivity and losses of MBP+ auditory nerve fibers were observed in the spiral ganglia of both the older human and aged mouse ears. This study demonstrates that immunostaining for MBP in combination with confocal microscopy provides a sensitive, reliable, and efficient method for assessing alterations of myelin sheaths in the auditory nerve. The results also suggest that myelin degeneration may play a critical role in the SGN loss and the subsequent decline of the auditory nerve function in presbyacusis. PMID:22496821

  1. Age-Related Decline in Cognitive Pain Modulation Induced by Distraction: Evidence From Event-Related Potentials.

    PubMed

    Zhou, Shu; Després, Olivier; Pebayle, Thierry; Dufour, André

    2015-09-01

    Distraction is known to reduce perceived pain but not always efficiently. Overlapping cognitive resources play a role in both pain processing and executive functions. We hypothesized that with aging, the analgesic effects of cognitive modulation induced by distraction would be reduced as a result of functional decline of frontal networks. Twenty-eight elderly and 28 young participants performed a tonic heat pain test with and without distraction (P + D vs P condition), and 2 executive tasks involving the frontal network (1-back [working memory] and go/no-go [response inhibition]), during which event-related potentials were recorded. A significant age-related difference in modulatory effect was observed during the pain-distraction test, with the older group reporting higher pain perception than the younger group during the P + D than during the P condition. Greater brain activity of early processes (P2 component) in both go/no-go and 1-back tasks correlated with less perceived pain during distraction in younger participants. For later processes, more cognitive control and attentional resources (increased N2 and P3 amplitude) needed for working memory processes were associated with greater pain perception in the older group. Inhibition processes were related to conscious distraction estimation in both groups. These findings indicate that cognitive processes subtended by resources in the frontal network, particularly working memory processes, are elicited more in elderly than in younger individuals for pain tolerance when an irrelevant task is performed simultaneously. Perspective: This study suggests that age-related declines in pain modulation are caused by functional degeneration of frontal cerebral networks, which may contribute to a higher prevalence of chronic pain. Analyzing the impact of frontal network function on pain modulation may assist in the development of more effective targeted treatment plans. PMID:26080043

  2. Age-related changes in human posture control: Motor coordination tests

    NASA Technical Reports Server (NTRS)

    Peterka, R. J.; Black, F. O.

    1989-01-01

    Postural responses to support surface displacements were measured in 214 normal human subjects ranging in age from 7 to 81 years. Motor tests measured leg muscle Electromyography (EMG) latencies, body sway, and the amplitude and timing of changes in center of pressure displacements in response to sudden forward and backward horizontal translations of the support surface upon which the subjects stood. There were small increases in both EMG latencies and the time to reach the peak amplitude of center of pressure responses with increasing age. The amplitude of center of pressure responses showed little change with age if the amplitude measures were normalized by a factor related to subject height. In general, postural responses to sudden translations showed minimal changes with age, and all age related trends which were identified were small relative to the variability within the population.

  3. Age-related changes in color appearance depend on unique-hue components

    NASA Astrophysics Data System (ADS)

    Okajima, Katsunori; Tsuchiya, Nao; Yamashita, Kazuyuki

    2002-06-01

    In order to compare color appearance as seen by elderly and young people, we conducted an experiment where the subjects responded to the color appearance of 75 color chips using a categorical color naming method and an elemental color scaling method. The results show that categorical color naming between elderly and young subjects is almost identical for most color chips, but there were significant differences in the elemental color scaling between the two age groups depending on unique-hue components. The differences in yellow and blue components between elderly and young subjects suggest that the neural mechanism of color vision in elderly people may over perform on constancy of color appearance so as to compensate for the age-related change of the human crystalline lens. In addition, the chromatic components in elderly subjects indicate higher values than those in young subjects for low saturation color chips, whereas the chromatic components in elderly subjects indicate lower values than those in young subjects when viewing high saturation color chips. These results show that the age-related changes of unique hue components strongly depend on saturation of colors, and suggest that the practical range of color appearance in elderly people is small in comparison with young people.

  4. Age-Related Changes in Hepatic Activity and Expression of Detoxification Enzymes in Male Rats

    PubMed Central

    Vyskočilová, Erika; Szotáková, Barbora; Skálová, Lenka; Bártíková, Hana; Hlaváčová, Jitka

    2013-01-01

    Process of aging is accompanied by changes in the biotransformation of xenobiotics and impairment of normal cellular functions by free radicals. Therefore, this study was designed to determine age-related differences in the activities and/or expressions of selected drug-metabolizing and antioxidant enzymes in young and old rats. Specific activities of 8 drug-metabolizing enzymes and 4 antioxidant enzymes were assessed in hepatic subcellular fractions of 6-week-old and 21-month-old male Wistar rats. Protein expressions of carbonyl reductase 1 (CBR1) and glutathione S-transferase (GST) were determined using immunoblotting. Remarkable age-related decrease in specific activities of CYP2B, CYP3A, and UDP-glucuronosyl transferase was observed, whereas no changes in activities of CYP1A2, flavine monooxygenase, aldo-keto reductase 1C, and antioxidant enzymes with advancing age were found. On the other hand, specific activity of CBR1 and GST was 2.4 folds and 5.6 folds higher in the senescent rats compared with the young ones, respectively. Interindividual variability in CBR1 activity increased significantly with rising age. We suppose that elevated activities of GST and CBR1 may protect senescent rats against xenobiotic as well as eobiotic electrophiles and reactive carbonyls, but they may alter metabolism of drugs, which are CBR1 and especially GSTs substrates. PMID:23971034

  5. Examining age-related shared variance between face cognition, vision, and self-reported physical health: a test of the common cause hypothesis for social cognition

    PubMed Central

    Olderbak, Sally; Hildebrandt, Andrea; Wilhelm, Oliver

    2015-01-01

    The shared decline in cognitive abilities, sensory functions (e.g., vision and hearing), and physical health with increasing age is well documented with some research attributing this shared age-related decline to a single common cause (e.g., aging brain). We evaluate the extent to which the common cause hypothesis predicts associations between vision and physical health with social cognition abilities specifically face perception and face memory. Based on a sample of 443 adults (17–88 years old), we test a series of structural equation models, including Multiple Indicator Multiple Cause (MIMIC) models, and estimate the extent to which vision and self-reported physical health are related to face perception and face memory through a common factor, before and after controlling for their fluid cognitive component and the linear effects of age. Results suggest significant shared variance amongst these constructs, with a common factor explaining some, but not all, of the shared age-related variance. Also, we found that the relations of face perception, but not face memory, with vision and physical health could be completely explained by fluid cognition. Overall, results suggest that a single common cause explains most, but not all age-related shared variance with domain specific aging mechanisms evident. PMID:26321998

  6. Examining age-related shared variance between face cognition, vision, and self-reported physical health: a test of the common cause hypothesis for social cognition.

    PubMed

    Olderbak, Sally; Hildebrandt, Andrea; Wilhelm, Oliver

    2015-01-01

    The shared decline in cognitive abilities, sensory functions (e.g., vision and hearing), and physical health with increasing age is well documented with some research attributing this shared age-related decline to a single common cause (e.g., aging brain). We evaluate the extent to which the common cause hypothesis predicts associations between vision and physical health with social cognition abilities specifically face perception and face memory. Based on a sample of 443 adults (17-88 years old), we test a series of structural equation models, including Multiple Indicator Multiple Cause (MIMIC) models, and estimate the extent to which vision and self-reported physical health are related to face perception and face memory through a common factor, before and after controlling for their fluid cognitive component and the linear effects of age. Results suggest significant shared variance amongst these constructs, with a common factor explaining some, but not all, of the shared age-related variance. Also, we found that the relations of face perception, but not face memory, with vision and physical health could be completely explained by fluid cognition. Overall, results suggest that a single common cause explains most, but not all age-related shared variance with domain specific aging mechanisms evident.

  7. Examining age-related shared variance between face cognition, vision, and self-reported physical health: a test of the common cause hypothesis for social cognition.

    PubMed

    Olderbak, Sally; Hildebrandt, Andrea; Wilhelm, Oliver

    2015-01-01

    The shared decline in cognitive abilities, sensory functions (e.g., vision and hearing), and physical health with increasing age is well documented with some research attributing this shared age-related decline to a single common cause (e.g., aging brain). We evaluate the extent to which the common cause hypothesis predicts associations between vision and physical health with social cognition abilities specifically face perception and face memory. Based on a sample of 443 adults (17-88 years old), we test a series of structural equation models, including Multiple Indicator Multiple Cause (MIMIC) models, and estimate the extent to which vision and self-reported physical health are related to face perception and face memory through a common factor, before and after controlling for their fluid cognitive component and the linear effects of age. Results suggest significant shared variance amongst these constructs, with a common factor explaining some, but not all, of the shared age-related variance. Also, we found that the relations of face perception, but not face memory, with vision and physical health could be completely explained by fluid cognition. Overall, results suggest that a single common cause explains most, but not all age-related shared variance with domain specific aging mechanisms evident. PMID:26321998

  8. Age-related changes of auditory brainstem responses in nonhuman primates.

    PubMed

    Ng, Chi-Wing; Navarro, Xochi; Engle, James R; Recanzone, Gregg H

    2015-07-01

    Nonhuman primates, compared with humans and rodents, have historically been far less used for studies of age-related hearing loss, primarily because of their long life span and high cost of maintenance. Strong similarities in genetics, anatomy, and neurophysiology of the auditory nervous system between humans and monkeys, however, could provide fruitful opportunities to enhance our understanding of hearing loss. The present study used a common, noninvasive technique for testing hearing sensitivity in humans, the auditory brainstem response (ABR), to assess the hearing of 48 rhesus macaques from 6 to 35 yr of age to clicks and tone stimuli between 0.5 and 16.0 kHz. Old monkeys, particularly those above 21.5 yr of age, had missing ABR waveforms at high frequencies. Regression analyses revealed that ABR threshold increased as a function of age at peaks II and IV simultaneously. In the suprathreshold hearing condition (70 dB peak sound pressure level), ABR-based audiograms similarly varied as a function of age such that old monkeys had smaller peak amplitudes and delayed latencies at low, middle, and high frequencies. Peripheral hearing differences remained a major influence associated with age-related changes in audiometric functions of old monkeys at a comparable sensation level across animals. The present findings suggest that hearing loss occurs in old monkeys across a wide range of frequencies and that these deficits increase in severity with age. Parallel to prior studies in monkeys, we found weak effects of sex on hearing, and future investigations are necessary to clarify its role in age-related hearing loss. PMID:25972589

  9. Age-related changes of auditory brainstem responses in nonhuman primates

    PubMed Central

    Ng, Chi-Wing; Navarro, Xochi; Engle, James R.

    2015-01-01

    Nonhuman primates, compared with humans and rodents, have historically been far less used for studies of age-related hearing loss, primarily because of their long life span and high cost of maintenance. Strong similarities in genetics, anatomy, and neurophysiology of the auditory nervous system between humans and monkeys, however, could provide fruitful opportunities to enhance our understanding of hearing loss. The present study used a common, noninvasive technique for testing hearing sensitivity in humans, the auditory brainstem response (ABR), to assess the hearing of 48 rhesus macaques from 6 to 35 yr of age to clicks and tone stimuli between 0.5 and 16.0 kHz. Old monkeys, particularly those above 21.5 yr of age, had missing ABR waveforms at high frequencies. Regression analyses revealed that ABR threshold increased as a function of age at peaks II and IV simultaneously. In the suprathreshold hearing condition (70 dB peak sound pressure level), ABR-based audiograms similarly varied as a function of age such that old monkeys had smaller peak amplitudes and delayed latencies at low, middle, and high frequencies. Peripheral hearing differences remained a major influence associated with age-related changes in audiometric functions of old monkeys at a comparable sensation level across animals. The present findings suggest that hearing loss occurs in old monkeys across a wide range of frequencies and that these deficits increase in severity with age. Parallel to prior studies in monkeys, we found weak effects of sex on hearing, and future investigations are necessary to clarify its role in age-related hearing loss. PMID:25972589

  10. A mutation in APP protects against Alzheimer's disease and age-related cognitive decline.

    PubMed

    Jonsson, Thorlakur; Atwal, Jasvinder K; Steinberg, Stacy; Snaedal, Jon; Jonsson, Palmi V; Bjornsson, Sigurbjorn; Stefansson, Hreinn; Sulem, Patrick; Gudbjartsson, Daniel; Maloney, Janice; Hoyte, Kwame; Gustafson, Amy; Liu, Yichin; Lu, Yanmei; Bhangale, Tushar; Graham, Robert R; Huttenlocher, Johanna; Bjornsdottir, Gyda; Andreassen, Ole A; Jönsson, Erik G; Palotie, Aarno; Behrens, Timothy W; Magnusson, Olafur T; Kong, Augustine; Thorsteinsdottir, Unnur; Watts, Ryan J; Stefansson, Kari

    2012-08-01

    The prevalence of dementia in the Western world in people over the age of 60 has been estimated to be greater than 5%, about two-thirds of which are due to Alzheimer's disease. The age-specific prevalence of Alzheimer's disease nearly doubles every 5 years after age 65, leading to a prevalence of greater than 25% in those over the age of 90 (ref. 3). Here, to search for low-frequency variants in the amyloid-β precursor protein (APP) gene with a significant effect on the risk of Alzheimer's disease, we studied coding variants in APP in a set of whole-genome sequence data from 1,795 Icelanders. We found a coding mutation (A673T) in the APP gene that protects against Alzheimer's disease and cognitive decline in the elderly without Alzheimer's disease. This substitution is adjacent to the aspartyl protease β-site in APP, and results in an approximately 40% reduction in the formation of amyloidogenic peptides in vitro. The strong protective effect of the A673T substitution against Alzheimer's disease provides proof of principle for the hypothesis that reducing the β-cleavage of APP may protect against the disease. Furthermore, as the A673T allele also protects against cognitive decline in the elderly without Alzheimer's disease, the two may be mediated through the same or similar mechanisms.

  11. Age-Related Changes in Corneal Deformation Dynamics Utilizing Scheimpflug Imaging

    PubMed Central

    Rogowska, Marta E.; Iskander, D. Robert

    2015-01-01

    Purpose To study age-related changes in corneal deformation response to air-puff applanation tonometry. Methods Fifty healthy subjects were recruited for a prospective study and divided into two equal age groups (≤ 28 and ≥ 50 years old). Up to three measurements by a corneal deformation analyser based on the Scheimpflug principle were performed on the left eye of each subject. Raw Scheimpflug images were used to extract changes in anterior and posterior corneal profiles, which were further modelled by an orthogonal series of Chebyshev polynomial functions. Time series of the polynomial coefficients of even order exhibited a dynamic behavior in which three distinct stages were recognized. A bilinear function was used to model the first and the third stage of corneal dynamics. Slope parameters of the bilinear fit were then tested between the two age groups using Wilcoxon rank sum test and two-way non-parametric ANOVA (Friedman) test. Results Statistically significant changes (Wilcoxon test, P<0.05) between the age groups were observed in the phase of the second applanation dynamics for the posterior corneal profile. In a two-way comparison, in which the corneal profile was used as a dependent variable, statistically significant changes (ANOVA/Friedman test, P = 0.017) between the groups were also observed for that phase. Conclusion Corneal biomechanics depend on age. The changes in corneal deformation dynamics, which correspond to mostly free return of the cornea to its original shape after the air pulse, indicate that the age related differences in corneal biomechanics are subtle but observable with high speed imaging. PMID:26460972

  12. Age-Related Changes in Transient and Oscillatory Brain Responses to Auditory Stimulation during Early Adolescence

    ERIC Educational Resources Information Center

    Poulsen, Catherine; Picton, Terence W.; Paus, Tomas

    2009-01-01

    Maturational changes in the capacity to process quickly the temporal envelope of sound have been linked to language abilities in typically developing individuals. As part of a longitudinal study of brain maturation and cognitive development during adolescence, we employed dense-array EEG and spatiotemporal source analysis to characterize…

  13. Is It Possible to Delay or Prevent Age-Related Cognitive Decline?

    PubMed

    Michel, Jean-Pierre

    2016-09-01

    Already in the 90s, Khachaturian stated that postponing dementia onset by five years would decrease the prevalence of the late onset dementia by 50%. After two decades of lack of success in dementia drug discovery and development, and knowing that worldwide, currently 36 million patients have been diagnosed with Alzheimer's disease, a number that will double by 2030 and triple by 2050, the World Health Organization and the Alzheimer's Disease International declared that prevention of cognitive decline was a 'public health priority.' Numerous longitudinal studies and meta-analyses were conducted to analyze the risk and protective factors for dementia. Among the 93 identified risk factors, seven major modifiable ones should be considered: low education, sedentary lifestyle, midlife obesity, midlife smoking, hypertension, diabetes, and midlife depression. Three other important modifiable risk factors should also be added to this list: midlife hypercholesterolemia, late life atrial fibrillation, and chronic kidney disease. After their identification, numerous authors attempted to establish dementia risk scores; however, the proposed values were not convincing. Identifying the possible interventions, able to either postpone or delay dementia has been an important challenge. Observational studies focused on a single life-style intervention increased the global optimism concerning these possibilities. However, a recent extensive literature review of the randomized control trials (RCTs) conducted before 2014 yielded negative results. The first results of RCTs of multimodal interventions (Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability, Multidomain Alzheimer Prevention Study, and Prediva) brought more optimism. Lastly, interventions targeting compounds of beta amyloid started in 2012 and no results have yet been published.

  14. Is It Possible to Delay or Prevent Age-Related Cognitive Decline?

    PubMed Central

    2016-01-01

    Already in the 90s, Khachaturian stated that postponing dementia onset by five years would decrease the prevalence of the late onset dementia by 50%. After two decades of lack of success in dementia drug discovery and development, and knowing that worldwide, currently 36 million patients have been diagnosed with Alzheimer's disease, a number that will double by 2030 and triple by 2050, the World Health Organization and the Alzheimer's Disease International declared that prevention of cognitive decline was a 'public health priority.' Numerous longitudinal studies and meta-analyses were conducted to analyze the risk and protective factors for dementia. Among the 93 identified risk factors, seven major modifiable ones should be considered: low education, sedentary lifestyle, midlife obesity, midlife smoking, hypertension, diabetes, and midlife depression. Three other important modifiable risk factors should also be added to this list: midlife hypercholesterolemia, late life atrial fibrillation, and chronic kidney disease. After their identification, numerous authors attempted to establish dementia risk scores; however, the proposed values were not convincing. Identifying the possible interventions, able to either postpone or delay dementia has been an important challenge. Observational studies focused on a single life-style intervention increased the global optimism concerning these possibilities. However, a recent extensive literature review of the randomized control trials (RCTs) conducted before 2014 yielded negative results. The first results of RCTs of multimodal interventions (Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability, Multidomain Alzheimer Prevention Study, and Prediva) brought more optimism. Lastly, interventions targeting compounds of beta amyloid started in 2012 and no results have yet been published. PMID:27688858

  15. Is It Possible to Delay or Prevent Age-Related Cognitive Decline?

    PubMed

    Michel, Jean-Pierre

    2016-09-01

    Already in the 90s, Khachaturian stated that postponing dementia onset by five years would decrease the prevalence of the late onset dementia by 50%. After two decades of lack of success in dementia drug discovery and development, and knowing that worldwide, currently 36 million patients have been diagnosed with Alzheimer's disease, a number that will double by 2030 and triple by 2050, the World Health Organization and the Alzheimer's Disease International declared that prevention of cognitive decline was a 'public health priority.' Numerous longitudinal studies and meta-analyses were conducted to analyze the risk and protective factors for dementia. Among the 93 identified risk factors, seven major modifiable ones should be considered: low education, sedentary lifestyle, midlife obesity, midlife smoking, hypertension, diabetes, and midlife depression. Three other important modifiable risk factors should also be added to this list: midlife hypercholesterolemia, late life atrial fibrillation, and chronic kidney disease. After their identification, numerous authors attempted to establish dementia risk scores; however, the proposed values were not convincing. Identifying the possible interventions, able to either postpone or delay dementia has been an important challenge. Observational studies focused on a single life-style intervention increased the global optimism concerning these possibilities. However, a recent extensive literature review of the randomized control trials (RCTs) conducted before 2014 yielded negative results. The first results of RCTs of multimodal interventions (Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability, Multidomain Alzheimer Prevention Study, and Prediva) brought more optimism. Lastly, interventions targeting compounds of beta amyloid started in 2012 and no results have yet been published. PMID:27688858

  16. Is It Possible to Delay or Prevent Age-Related Cognitive Decline?

    PubMed Central

    2016-01-01

    Already in the 90s, Khachaturian stated that postponing dementia onset by five years would decrease the prevalence of the late onset dementia by 50%. After two decades of lack of success in dementia drug discovery and development, and knowing that worldwide, currently 36 million patients have been diagnosed with Alzheimer's disease, a number that will double by 2030 and triple by 2050, the World Health Organization and the Alzheimer's Disease International declared that prevention of cognitive decline was a 'public health priority.' Numerous longitudinal studies and meta-analyses were conducted to analyze the risk and protective factors for dementia. Among the 93 identified risk factors, seven major modifiable ones should be considered: low education, sedentary lifestyle, midlife obesity, midlife smoking, hypertension, diabetes, and midlife depression. Three other important modifiable risk factors should also be added to this list: midlife hypercholesterolemia, late life atrial fibrillation, and chronic kidney disease. After their identification, numerous authors attempted to establish dementia risk scores; however, the proposed values were not convincing. Identifying the possible interventions, able to either postpone or delay dementia has been an important challenge. Observational studies focused on a single life-style intervention increased the global optimism concerning these possibilities. However, a recent extensive literature review of the randomized control trials (RCTs) conducted before 2014 yielded negative results. The first results of RCTs of multimodal interventions (Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability, Multidomain Alzheimer Prevention Study, and Prediva) brought more optimism. Lastly, interventions targeting compounds of beta amyloid started in 2012 and no results have yet been published.

  17. Age-related changes in rat cerebellar basket cells: a quantitative study using unbiased stereological methods

    PubMed Central

    HENRIQUE, RUI M. F.; ROCHA, EDUARDO; REIS, ALCINDA; MARCOS, RICARDO; OLIVEIRA, MARIA H.; SILVA, MARIA W.; MONTEIRO, ROGÉRIO A. F.

    2001-01-01

    Cortical cerebellar basket cells are stable postmitotic cells; hence, they are liable to endure age-related changes. Since the cerebellum is a vital organ for the postural control, equilibrium and motor coordination, we aimed to determine the quantitative morphological changes in those interneurons with the ageing process, using unbiased techniques. Material from the cerebellar cortex (Crus I and Crus II) was collected from female rats aged 2, 6, 9, 12, 15, 18, 21 and 24 mo (5 animals per each age group), fixed by intracardiac perfusion, and processed for transmission electron microscopy, using conventional techniques. Serial semithin sections were obtained (5 blocks from each rat), enabling the determination of the number-weighted mean nuclear volume (by the nucleator method). On ultrathin sections, 25 cell profiles from each animal were photographed. The volume density of the nucleus, ground substance, mitochondria, Golgi apparatus (Golgi) and dense bodies (DB), and the mean surface density of the rough endoplasmic reticulum (RER) were determined, by point counting, using a morphometric grid. The mean total volumes of the soma and organelles and the mean total surface area of the RER [s̄N (RER)] were then calculated. The results were analysed with 1-way ANOVA; posthoc pairwise comparisons of group means were performed using the Newman-Keuls test. The relation between age and each of the parameters was studied by regression analysis. Significant age-related changes were observed for the mean volumes of the soma, ground substance, Golgi, DB, and s̄N (RER). Positive linear trends were found for the mean volumes of the ground substance, Golgi, and DB; a negative linear trend was found for the s̄N (RER). These results indicate that rat cerebellar basket cells endure important age-related changes. The significant decrease in the s̄N (RER) may be responsible for a reduction in the rate of protein synthesis. Additionally, it may be implicated in a cascade of events

  18. Neurophysiological correlates of age-related changes in working memory capacity.

    PubMed

    Mattay, Venkata S; Fera, Francesco; Tessitore, Alessandro; Hariri, Ahmad R; Berman, Karen F; Das, Saumitra; Meyer-Lindenberg, Andreas; Goldberg, Terry E; Callicott, Joseph H; Weinberger, Daniel R

    2006-01-01

    Cognitive abilities such as working memory (WM) capacity decrease with age. To determine the neurophysiological correlates of age-related reduction in working memory capacity, we studied 10 young subjects (<35 years of age; mean age=29) and twelve older subjects (>55 years of age; mean age=59) with whole brain blood oxygenation-level dependent (BOLD) fMRI on a 1.5 T GE MR scanner using a SPIRAL FLASH pulse sequence (TE=24 ms, TR=56 ms, FA=60 degrees , voxel dimensions=3.75 mm(3)). Subjects performed a modified version of the "n" back working memory task at different levels of increasing working memory load (1-Back, 2-Back and 3-Back). Older subjects performed as well as the younger subjects at 1-Back (p=0.4), but performed worse than the younger subjects at 2-Back (p<0.01) and 3-Back (p=0.06). Older subjects had significantly longer reaction time (RT) than younger subjects (p<0.04) at all levels of task difficulty. Image analysis using SPM 99 revealed a similar distribution of cortical activity between younger and older subjects at all task levels. However, an analysis of variance revealed a significant group x task interaction in the prefrontal cortex bilaterally; within working memory capacity, as in 1-Back when the older subjects performed as well as the younger subjects, they showed greater prefrontal cortical (BA 9) activity bilaterally. At higher working memory loads, however, when they performed worse then the younger subjects, the older subjects showed relatively reduced activity in these prefrontal regions. These data suggest that, within capacity, compensatory mechanisms such as additional prefrontal cortical activity are called upon to maintain proficiency in task performance. As cognitive demand increases, however, they are pushed past a threshold beyond which physiological compensation cannot be made and, a decline in performance occurs. PMID:16213083

  19. Decrease in age-related tau hyperphosphorylation and cognitive improvement following vitamin D supplementation are associated with modulation of brain energy metabolism and redox state.

    PubMed

    Briones, T L; Darwish, H

    2014-03-14

    In the present study we examined whether vitamin D supplementation can reduce age-related tau hyperphosphorylation and cognitive impairment by enhancing brain energy homeostasis and protein phosphatase 2A (PP2A) activity, and modulating the redox state. Male F344 rats aged 20 months (aged) and 6 months (young) were randomly assigned to either vitamin D supplementation or no supplementation (control). Rats were housed in pairs and the supplementation group (n=10 young and n=10 aged) received subcutaneous injections of vitamin D (1, α25-dihydroxyvitamin D3) for 21 days. Control animals (n=10 young and n=10 aged) received equal volume of normal saline and behavioral testing in the water maze started on day 14 after the initiation of vitamin D supplementation. Tau phosphorylation, markers of brain energy metabolism (ADP/ATP ratio and adenosine monophosphate-activated protein kinase) and redox state (levels of reactive oxygen species, activity of superoxide dismutase, and glutathione levels) as well as PP2A activity were measured in hippocampal tissues. Our results extended previous findings that: (1) tau phosphorylation significantly increased during aging; (2) markers of brain energy metabolism and redox state are significantly decreased in aging; and (3) aged rats demonstrated significant learning and memory impairment. More importantly, we found that age-related changes in brain energy metabolism, redox state, and cognitive function were attenuated by vitamin D supplementation. No significant differences were seen in tau hyperphosphorylation, markers of energy metabolism and redox state in the young animal groups. Our data suggest that vitamin D ameliorated the age-related tau hyperphosphorylation and cognitive decline by enhancing brain energy metabolism, redox state, and PP2A activity making it a potentially useful therapeutic option to alleviate the effects of aging.

  20. Age-related neurochemical changes in the rhesus macaque inferior colliculus

    PubMed Central

    Engle, James R.; Gray, Daniel T.; Turner, Heather; Udell, Julia B.; Recanzone, Gregg H.

    2014-01-01

    Age-related hearing loss (ARHL) is marked by audiometric hearing deficits that propagate along the auditory pathway. Neurochemical changes as a function of aging have also been identified in neurons along the auditory pathway in both rodents and carnivores, however, very little is known about how these neurochemicals change in the non-human primate. To examine how these compensatory neurochemical changes relate to normal aging and audiometric sensitivity along the auditory pathway, we collected auditory brainstem responses (ABRs) and brain specimens from seven rhesus monkeys spanning in age from 15 to 35 years old, and examined the relationship between click evoked ABR thresholds and the ABR evoked pure tone average (PTA) and changes in the number of parvalbumin and NADPH-diaphorase positive cells in the auditory midbrain. We found that the number of parvalbumin positive cells in the central nucleus and the surrounding cortex regions of the inferior colliculus were strongly correlated with advancing age and ABR PTA. We also found that the numbers of NADPHd positive cells in these same regions were not associated with normal aging or changes in the ABR thresholds. These findings suggest that the auditory midbrain undergoes an up-regulation of parvalbumin expressing neurons with aging that is related to changes in the processing of frequencies across the audiometric range. PMID:24795627

  1. Age-Related Changes in Performance and Recovery Kinetics in Masters Athletes: A Narrative Review.

    PubMed

    Borges, Nattai; Reaburn, Peter; Driller, Matthew; Argus, Christos

    2016-01-01

    Despite increasing participation rates in masters sport and extensive research examining age-related changes in performance, little is known about the effect of age on recovery kinetics in masters athletes. This narrative review focuses on the relationship between aging and sport participation, and the effect on both performance and recovery following an exercise bout. Current research suggests the effect of age on performance and recovery may be smaller than originally suggested and that increasing sedentary lifestyles appear to play a larger role in any observed decrements in performance and recovery in masters athletes. Currently, it appears that performance decrements are inevitable with age. However, performance capacities can be maintained through systematic physical training. Moreover, the limited current research suggests there may be an age effect on recovery kinetics following an exercise bout, although further research is required to understand the acute and chronic recovery processes in the masters athlete.

  2. Age-related changes in the thymus gland: CT-pathologic correlation

    SciTech Connect

    Moore, A.V.; Korobkin, M.; Olanow, W.; Heaston, D.K.; Ram, P.C.; Dunnick, N.R.; Silverman, P.M.

    1983-08-01

    Recent reports suggest that computed tomography (CT) is useful for thymoma detection in patients with myasthenia gravis. However, that usefulness may be conditioned by the state of the normal thymus. To examine this concept, the CT findings in 64 consecutive patients with histologic confirmation of thymic status after thymectomy or thymic biopsy during mediastinal exploration were reviewed. The normal thymus has a bilobed, arrowhead-shaped cross section at all ages, with gradual focal or diffuse fatty infiltration of the parenchyma usually occurring between 20 and 40 years of age. A thymoma is usually a spherical or oval mass, often producing a focal, distinct bulge in the adjacent pleural reflection. The differentiation of thymoma from normal thymus should be possible in most patients if age-related changes in the normal gland are appreciated.

  3. Age-related changes in mechanical properties of the Achilles tendon.

    PubMed

    Waugh, C M; Blazevich, A J; Fath, F; Korff, T

    2012-02-01

    The stiffness of a tendon, which influences muscular force transfer to the skeleton and increases during childhood, is dependent on its material properties and dimensions, both of which are influenced by chronic loading. The aims of this study were to: (i) determine the independent contributions of body mass, force production capabilities and tendon dimensions to tendon stiffness during childhood; and (ii) descriptively document age-related changes in tendon mechanical properties and dimensions. Achilles tendon mechanical and material properties were determined in 52 children (5-12 years) and 19 adults. Tendon stiffness and Young's modulus (YM) were calculated as the slopes of the force-elongation and stress-strain curves, respectively. Relationships between stiffness vs. age, mass and force, and between YM vs. age, mass and stress were determined by means of polynomial fits and multiple regression analyses. Mass was found to be the best predictor of stiffness, whilst stress was best related to YM (< 75 and 51% explained variance, respectively). Combined, mass and force accounted for up to 78% of stiffness variation. Up to 61% of YM variability could be explained using a combination of mass, stress and age. These results demonstrate that age-related increases in tendon stiffness are largely attributable to increased tendon loading from weight-bearing tasks and increased plantarflexor force production, as well as tendon growth. Moreover, our results suggest that chronic increases in tendon loading during childhood result in microstructural changes which increase the tendon's YM. Regarding the second aim, peak stress increased from childhood to adulthood due to greater increases in strength than tendon cross-sectional area. Peak strain remained constant as a result of parallel increases in tendon length and peak elongation. The differences in Achilles tendon properties found between adults and children are likely to influence force production, and ultimately movement

  4. Age-related changes in midbrain dopaminergic regulation of the human reward system

    PubMed Central

    Dreher, Jean-Claude; Meyer-Lindenberg, Andreas; Kohn, Philip; Berman, Karen Faith

    2008-01-01

    The dopamine system, which plays a crucial role in reward processing, is particularly vulnerable to aging. Significant losses over a normal lifespan have been reported for dopamine receptors and transporters, but very little is known about the neurofunctional consequences of this age-related dopaminergic decline. In animals, a substantial body of data indicates that dopamine activity in the midbrain is tightly associated with reward processing. In humans, although indirect evidence from pharmacological and clinical studies also supports such an association, there has been no direct demonstration of a link between midbrain dopamine and reward-related neural response. Moreover, there are no in vivo data for alterations in this relationship in older humans. Here, by using 6-[18F]FluoroDOPA (FDOPA) positron emission tomography (PET) and event-related 3T functional magnetic resonance imaging (fMRI) in the same subjects, we directly demonstrate a link between midbrain dopamine synthesis and reward-related prefrontal activity in humans, show that healthy aging induces functional alterations in the reward system, and identify an age-related change in the direction of the relationship (from a positive to a negative correlation) between midbrain dopamine synthesis and prefrontal activity. These results indicate an age-dependent dopaminergic tuning mechanism for cortical reward processing and provide system-level information about alteration of a key neural circuit in healthy aging. Taken together, our findings provide an important characterization of the interactions between midbrain dopamine function and the reward system in healthy young humans and older subjects, and identify the changes in this regulatory circuit that accompany aging. PMID:18794529

  5. Spatiotemporal Dependency of Age-Related Changes in Brain Signal Variability

    PubMed Central

    McIntosh, A. R.; Vakorin, V.; Kovacevic, N.; Wang, H.; Diaconescu, A.; Protzner, A. B.

    2014-01-01

    Recent theoretical and empirical work has focused on the variability of network dynamics in maturation. Such variability seems to reflect the spontaneous formation and dissolution of different functional networks. We sought to extend these observations into healthy aging. Two different data sets, one EEG (total n = 48, ages 18–72) and one magnetoencephalography (n = 31, ages 20–75) were analyzed for such spatiotemporal dependency using multiscale entropy (MSE) from regional brain sources. In both data sets, the changes in MSE were timescale dependent, with higher entropy at fine scales and lower at more coarse scales with greater age. The signals were parsed further into local entropy, related to information processed within a regional source, and distributed entropy (information shared between two sources, i.e., functional connectivity). Local entropy increased for most regions, whereas the dominant change in distributed entropy was age-related reductions across hemispheres. These data further the understanding of changes in brain signal variability across the lifespan, suggesting an inverted U-shaped curve, but with an important qualifier. Unlike earlier in maturation, where the changes are more widespread, changes in adulthood show strong spatiotemporal dependence. PMID:23395850

  6. Age-related changes in the function and structure of the peripheral sensory pathway in mice.

    PubMed

    Canta, Annalisa; Chiorazzi, Alessia; Carozzi, Valentina Alda; Meregalli, Cristina; Oggioni, Norberto; Bossi, Mario; Rodriguez-Menendez, Virginia; Avezza, Federica; Crippa, Luca; Lombardi, Raffaella; de Vito, Giuseppe; Piazza, Vincenzo; Cavaletti, Guido; Marmiroli, Paola

    2016-09-01

    This study is aimed at describing the changes occurring in the entire peripheral nervous system sensory pathway along a 2-year observation period in a cohort of C57BL/6 mice. The neurophysiological studies evidenced significant differences in the selected time points corresponding to childhood, young adulthood, adulthood, and aging (i.e., 1, 7, 15, and 25 months of age), with a parabolic course as function of time. The pathological assessment allowed to demonstrate signs of age-related changes since the age of 7 months, with a remarkable increase in both peripheral nerves and dorsal root ganglia at the subsequent time points. These changes were mainly in the myelin sheaths, as also confirmed by the Rotating-Polarization Coherent-Anti-stokes-Raman-scattering microscopy analysis. Evident changes were also present at the morphometric analysis performed on the peripheral nerves, dorsal root ganglia neurons, and skin biopsies. This extensive, multimodal characterization of the peripheral nervous system changes in aging provides the background for future mechanistic studies allowing the selection of the most appropriate time points and readouts according to the investigation aims. PMID:27459934

  7. Common cell biologic and biochemical changes in aging and age-related diseases of the eye: Toward new therapeutic approaches to age-related ocular diseases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reviews of information about age related macular degeneration (AMD), cataract, and glaucoma make it apparent that while each eye tissue has its own characteristic metabolism, structure and function, there are common perturbations to homeostasis that are associated with age-related dysfunction. The c...

  8. Combined effects of physical exercise and education on age-related cortical thinning in cognitively normal individuals

    PubMed Central

    Lee, Jin San; Shin, Hee Young; Kim, Hee Jin; Jang, Young Kyoung; Jung, Na-Yeon; Lee, Juyoun; Kim, Yeo Jin; Chun, Phillip; Yang, Jin-Ju; Lee, Jong-Min; Kang, Mira; Park, Key-Chung; Na, Duk L.; Seo, Sang Won

    2016-01-01

    We investigated the association between self-reported physical exercise and cortical thickness in a large sample of cognitively normal individuals. We also determined whether a combination of physical exercise and education had more protective effects on age-related cortical thinning than either parameter alone. A total of 1,842 participants were included in this analysis. Physical exercise was assessed using a questionnaire regarding intensity, frequency, and duration. Cortical thickness was measured using a surface-based method. Longer duration of exercise (≥1 hr/day), but not intensity or frequency, was associated with increased mean cortical thickness globally (P-value = 0.013) and in the frontal regions (P-value = 0.007). In particular, the association of exercise with cortical thinning had regional specificity in the bilateral dorsolateral prefrontal, precuneus, left postcentral, and inferior parietal regions. The combination of higher exercise level and higher education level showed greater global and frontal mean thickness than either parameter alone. Testing for a trend with the combination of high exercise level and high education level confirmed this finding (P-value = 0.001–0.003). Our findings suggest that combined exercise and education have important implications for brain health, especially considering the paucity of known protective factors for age-related cortical thinning. PMID:27063336

  9. Age-Related Changes in the Anterior Segment Biometry During Accommodation

    PubMed Central

    Shao, Yilei; Tao, Aizhu; Jiang, Hong; Mao, Xinjie; Zhong, Jianguang; Shen, Meixiao; Lu, Fan; Xu, Zhe; Karp, Carol L.; Wang, Jianhua

    2015-01-01

    Purpose. We investigated the dynamic response of human accommodative elements as a function of age during accommodation using synchronized spectral domain optical coherence tomography devices (SD-OCT). Methods. We enrolled 33 left eyes from 33 healthy subjects (age range, 20–39 years, 17 males and 16 females). Two SD-OCT devices were synchronized to simultaneously image the anterior segment through pupil and the ciliary muscle during 6.00 diopter (D) accommodation for approximately 3.7 seconds in two repeated measurements. The anterior segment parameters included the lens thickness (LT), radius of curvature of the lens anterior surface (LAC), maximum thickness of ciliary muscle (CMTMAX), and anterior length of the ciliary muscle (CMAL). A first-order exponential equation was used to fit the dynamic changes during accommodation. The age-related changes in the dynamic response and their relationship were calculated and compared. Results. The amplitude (r = −0.40 and 0.53 for LT and LAC, respectively) and peak velocity (r = −0.65 and 0.71 for LT and LAC, respectively) of the changes in LT and LAC significantly decreased with age (P < 0.05), whereas the parameters of the ciliary muscle remained unchanged (P > 0.05), except for the peak velocity of the CMAL (r = 0.44, P = 0.01). The difference in the time constant between the lens reshaping (LT and LAC) and CMTMAX increased with age (r = 0.46 and 0.57 for LT and LAC, respectively, P < 0.01). The changes in LT and LAC per millimeter of CMTMAX change decreased with age (r = −0.52 and −0.34, respectively, P < 0.05). The ciliary muscle forward movement correlated with the lens deformation (r = −0.35 and 0.40 for amplitude, while r = 0.36 and 0.58 for time constant, respectively, P < 0.05). Conclusions. Age-related changes in the lens reshaping and ciliary muscle forward movement were found. Lens reshaping was much slower than the contraction of the ciliary muscle, especially in aging eyes, and this process

  10. Low-Dose, Ionizing Radiation and Age-Related Changes in Skeletal Microarchitecture

    DOE PAGES

    Alwood, Joshua S.; Kumar, Akhilesh; Tran, Luan H.; Wang, Angela; Limoli, Charles L.; Globus, Ruth K.

    2012-01-01

    Osteoporosis can profoundly affect the aged as a consequence of progressive bone loss; high-dose ionizing radiation can cause similar changes, although less is known about lower doses (≤100 cGy). We hypothesized that exposure to relatively low doses of gamma radiation accelerates structural changes characteristic of skeletal aging. Mice (C57BL/6J-10 wk old, male) were irradiated (total body; 0-sham, 1, 10 or 100 cGy 137 Cs) and tissues harvested on the day of irradiation, 1 or 4 months later. Microcomputed tomography was used to quantify microarchitecture of high turnover, cancellous bone. Irradiation at 100 cGy caused transient microarchitectural changes over one month that were only evidentmore » at longer times in controls (4 months). Ex vivo bone cell differentiation from the marrow was unaffected by gamma radiation. In conclusion, acute ionizing gamma irradiation at 100 cGy (but not at 1 cGy or 10 cGy) exacerbated microarchitectural changes normally found during progressive, postpubertal aging prior to the onset of age-related osteoporosis.« less

  11. A four-component model of age-related memory change.

    PubMed

    Healey, M Karl; Kahana, Michael J

    2016-01-01

    We develop a novel, computationally explicit, theory of age-related memory change within the framework of the context maintenance and retrieval (CMR2) model of memory search. We introduce a set of benchmark findings from the free recall and recognition tasks that include aspects of memory performance that show both age-related stability and decline. We test aging theories by lesioning the corresponding mechanisms in a model fit to younger adult free recall data. When effects are considered in isolation, many theories provide an adequate account, but when all effects are considered simultaneously, the existing theories fail. We develop a novel theory by fitting the full model (i.e., allowing all parameters to vary) to individual participants and comparing the distributions of parameter values for older and younger adults. This theory implicates 4 components: (a) the ability to sustain attention across an encoding episode, (b) the ability to retrieve contextual representations for use as retrieval cues, (c) the ability to monitor retrievals and reject intrusions, and (d) the level of noise in retrieval competitions. We extend CMR2 to simulate a recognition memory task using the same mechanisms the free recall model uses to reject intrusions. Without fitting any additional parameters, the 4-component theory that accounts for age differences in free recall predicts the magnitude of age differences in recognition memory accuracy. Confirming a prediction of the model, free recall intrusion rates correlate positively with recognition false alarm rates. Thus, we provide a 4-component theory of a complex pattern of age differences across 2 key laboratory tasks.

  12. Effect of Bcl-2 rs956572 polymorphism on age-related gray matter volume changes.

    PubMed

    Liu, Mu-En; Huang, Chu-Chung; Yang, Albert C; Tu, Pei-Chi; Yeh, Heng-Liang; Hong, Chen-Jee; Chen, Jin-Fan; Liou, Ying-Jay; Lin, Ching-Po; Tsai, Shih-Jen

    2013-01-01

    The anti-apoptotic protein B-cell CLL/lymphoma 2 (Bcl-2) gene is a major regulator of neural plasticity and cellular resilience. Recently, the Bcl-2 rs956572 single nucleotide polymorphism was proposed to be a functional allelic variant that modulates cellular vulnerability to apoptosis. Our cross-sectional study investigated the genetic effect of this Bcl-2 polymorphism on age-related decreases in gray matter (GM) volume across the adult lifespan. Our sample comprised 330 healthy volunteers (191 male, 139 female) with a mean age of 56.2±22.0 years (range: 21-92). Magnetic resonance imaging and genotyping of the Bcl-2 rs956572 were performed for each participant. The differences in regional GM volumes between G homozygotes and A-allele carriers were tested using optimized voxel-based morphometry. The association between the Bcl-2 rs956572 polymorphism and age was a predictor of regional GM volumes in the right cerebellum, bilateral lingual gyrus, right middle temporal gyrus, and right parahippocampal gyrus. We found that the volume of these five regions decreased with increasing age (all P<.001). Moreover, the downward slope was steeper among the Bcl-2 rs956572 A-allele carriers than in the G-homozygous participants. Our data provide convergent evidence for the genetic effect of the Bcl-2 functional allelic variant in brain aging. The rs956572 G-allele, which is associated with significantly higher Bcl-2 protein expression and diminished cellular sensitivity to stress-induced apoptosis, conferred a protective effect against age-related changes in brain GM volume, particularly in the cerebellum. PMID:23437205

  13. Age-related changes in hypocretin (orexin) immunoreactivity in the cat brainstem.

    PubMed

    Zhang, Jian Hua; Sampogna, Sharon; Morales, Francisco R; Chase, Michael H

    2002-03-15

    Terminals of hypothalamic hypocretin-containing neurons are observed within brainstem nuclei involved in the control of sleep and wakefulness. Because aged humans, cats and other species exhibit changes in sleep and wakefulness in old age, we were interested in examining age-related changes in hypocretin/orexin projections to the following brainstem regions which are associated with the regulation of sleep and wakefulness: the dorsal raphe nucleus, the laterodorsal tegmental nucleus, the pedunculo-pontine tegmental nucleus and the locus coeruleus. Based upon the results of immunohistochemical determinations, in all the regions examined, round or oval "spot-like" structures were observed in aged cats. Many of these "spot-like" structures resembled enlarged varicosities of a nature that would be expected to disrupt hypocretin neurotransmission. In addition, a site-specific decrease in immunostaining was observed in the locus coeruleus in old cats compared with adult controls; this result likely reflects a decrease in the number of labeled fibers, which indicates that there occurs a degeneration of hypocretinergic function in conjunction with old age. The proceeding changes may account for some of sleep-wake disturbance which are observed in aged animals as well as elderly humans. PMID:11879811

  14. Age related changes and osteochondrosis in swine articular and epiphyseal cartilage: light ane electron microscopy.

    PubMed

    Bhatnagar, R; Christian, R G; Nakano, T; Aherne, F X; Thompson, J R

    1981-04-01

    Age related changes and osteochondrosis in swine were studied using light microscopy and electron microscopy in articular cartilage and light microscopy and epiphyseal cartilage of swine from three days to 30 weeks of age. Thickness, cellularity and vascularity of both the epiphyseal and articular cartilage, decreased as the swine aged. Osteochondrotic changes included formation of "plugs" of cartilage indicating localized failure of ossification and separation and space formation in epiphyseal cartilage. Eosinophilic streaks and space formation in epiphyseal cartilage was observed in relation to epiphyseal separation. Electron microscopy showed a continuous fibrillar layer on the surface of the cartilage corresponding to the lamina splendens of light microscopy. This layer increased in the thickness and showed accumulation of amorphous material between the fibrils with aging. In the matrix, the orientation and distribution of the collagen fibers changed with growth and thicker fibers with clear sub banding were more common in older age groups. Also, necrotic cells, glycogen containing bodies and cellular debris were noticed in the matrix of normal cartilage in old animals. Chondrocytes in the younger cartilage showed accumulation of organelles responsible for protein synthesis; while Golgi bodies, vesicles, lysosomes, well developed foot processes and other inclusions were noticed in older cartilage. Cartilage erosions had a clumped and disrupted lamina splendens on the surface and electron lucent patches in the ground substances of the matrix and chondrocyte cytoplasm. PMID:7260732

  15. [Age-related changes in the rat lacrimal gland: specific morphology and unknown nature].

    PubMed

    Gancharova, O S; Manskikh, V N

    2014-01-01

    The rat lacrimal apparatus includes several glands; among them, the exorbital gland plays the central role. Its parenchyma and stroma undergo prominent morphologic changes with age. The parenchymal transformation includes metaplasia of some of its acini and their turning into Harderian gland-like structures (harderization), accumulation of gland ducts ("ductularization"), and morphologic dysplasia-cytomegaly, karyomegaly, and'cell and nuclearpolymorphism in the other part of acini. All these transformations are hormone-dependent andsex-specific: theyoften appear in males. On the final stages of age-related transformations, the lacrimal gland tissue is morphologically similar to the neoplasm and has neoplastic morphology but no other features of a tumor. Therefore, the rat lacrimal gland is an interesting object to study tissue and cell atypia. In the rat glandular stroma, lymphocytic infiltration and fibrosis appear with age; these changes are similar to processes taking place in human lacrimal apparatus involved in the pathogenesis of senile dry eye syndrome. The spontaneous changes in the rat lacrimal gland, predominantly in male rats, can be used as a model of the human lacrimal apparatus disorders.

  16. Age-related changes in the elemental constituents and molecular behaviour of bone.

    PubMed

    Rai, D V; Darbari, R; Aggarwal, L M

    2005-04-01

    Age-related changes in bone composition within the age groups of 30, 60, 120 and 180 days in rats have been studied using thermogravimetery, elemental analysis and energy dispersive Xray (ED X-ray). The structural changes in rats the bone samples were monitored by IR spectroscopy. The main constituents of hydroxyapatite, namely Ca, P and their oxides were analyzed. Organic changes, such as C and N contents in the matrix were found to have a predominant role in the initial development of the bone. An incremental increase in the mineral content of bone with advancing age was also observed. Elemental composition (C and N contents) was observed to be independent of age at the initial stages. The amount of Ca and its oxide content was found to increase, and the P and its oxides showed a decreasing trend, with the advancing age. IR spectra revealed that the mineral phase comprised both amorphous and crystalline hydroxyapatite, even at maturity; the amorphous content being higher at the earlier stages (14.09%, at 30 days), but was gradually replaced by crystalline component with advancing age (63.09% at 180 days). The present data may be useful in explaining the ageing phenomenon and helpful in understanding the bone growth and remodeling.

  17. Age-related changes in petal membranes from attached and detached rose flowers.

    PubMed

    Itzhaki, H; Borochov, A; Mayak, S

    1990-11-01

    Changes in petal membrane properties during aging were studied in cut and in attached rose flowers (Rosa hybrida L., cv Mercedes). Both cut and attached flowers exhibited a growth phase characterized by an increase in fresh weight and an accumulation of membrane components. The growth phase, which was more pronounced in the attached than in the cut flowers, was followed by a senescence phase, characterized by a decrease in fresh weight and a decline in membrane components. In cut flowers, both the growth and the senescence phases were accompanied by a decrease in membrane fluidity and in the ratio of unsaturated to saturated fatty acids, but the ratio of sterol to phospholipid increased. In attached flowers, while both the membrane fluidity and the sterol-to-phospholipid ratio remained unchanged during the growth phase, the senescence phase was accompanied (as in cut flowers) by a decrease in membrane fluidity and an increase in the sterol-to-phospholipid ratio. Unlike in cut flowers, however, the age-related changes in the ratio of unsaturation of fatty acids were not correlated with those of fluidity. Changes in the saturation of phospholipid acyl chains are commonly thought to influence membrane fluidity. Our observations question this view and suggest instead that the ratio of sterol to phospholipid may play the major role in maintaining membrane lipid fluidity.

  18. Age-Related Declines in General Cognitive Abilities of Balb/C Mice and General Activity Are Associated with Disparities in Working Memory, Body Weight, and General Activity

    ERIC Educational Resources Information Center

    Matzel, Louis D.; Grossman, Henya; Light, Kenneth; Townsend, David; Kolata, Stefan

    2008-01-01

    A defining characteristic of age-related cognitive decline is a deficit in general cognitive performance. Here we use a testing and analysis regimen that allows us to characterize the general learning abilities of young (3-5 mo old) and aged (19-21 mo old) male and female Balb/C mice. Animals' performance was assessed on a battery of seven diverse…

  19. Age-Related Changes in Predictive Capacity Versus Internal Model Adaptability: Electrophysiological Evidence that Individual Differences Outweigh Effects of Age

    PubMed Central

    Bornkessel-Schlesewsky, Ina; Philipp, Markus; Alday, Phillip M.; Kretzschmar, Franziska; Grewe, Tanja; Gumpert, Maike; Schumacher, Petra B.; Schlesewsky, Matthias

    2015-01-01

    Hierarchical predictive coding has been identified as a possible unifying principle of brain function, and recent work in cognitive neuroscience has examined how it may be affected by age–related changes. Using language comprehension as a test case, the present study aimed to dissociate age-related changes in prediction generation versus internal model adaptation following a prediction error. Event-related brain potentials (ERPs) were measured in a group of older adults (60–81 years; n = 40) as they read sentences of the form “The opposite of black is white/yellow/nice.” Replicating previous work in young adults, results showed a target-related P300 for the expected antonym (“white”; an effect assumed to reflect a prediction match), and a graded N400 effect for the two incongruous conditions (i.e. a larger N400 amplitude for the incongruous continuation not related to the expected antonym, “nice,” versus the incongruous associated condition, “yellow”). These effects were followed by a late positivity, again with a larger amplitude in the incongruous non-associated versus incongruous associated condition. Analyses using linear mixed-effects models showed that the target-related P300 effect and the N400 effect for the incongruous non-associated condition were both modulated by age, thus suggesting that age-related changes affect both prediction generation and model adaptation. However, effects of age were outweighed by the interindividual variability of ERP responses, as reflected in the high proportion of variance captured by the inclusion of by-condition random slopes for participants and items. We thus argue that – at both a neurophysiological and a functional level – the notion of general differences between language processing in young and older adults may only be of limited use, and that future research should seek to better understand the causes of interindividual variability in the ERP responses of older adults and its relation to

  20. A critical review of Vitamin C for the prevention of age-related cognitive decline and Alzheimer’s disease

    PubMed Central

    Harrison, Fiona E

    2013-01-01

    Antioxidants in the diet have long been thought to confer some level of protection against the oxidative damage that is involved in the pathology of Alzheimer’s disease as well as general cognitive decline in normal aging. Nevertheless, support for this hypothesis in the literature is equivocal. In the case of vitamin C (ascorbic acid) in particular, lack of consideration of some of the specific features of vitamin C metabolism has led to studies in which classification of participants according to vitamin C status is inaccurate, and the absence of critical information precludes the drawing of appropriate conclusions. Vitamin C levels in plasma are not always reported, and estimated daily intake from food diaries may not be accurate or reflect actual plasma values. The ability to transport ingested vitamin C from the intestines into blood is limited by the saturable sodium-dependent vitamin C transporter (SVCT1) and thus very high intakes, and the use of supplements are often erroneously considered to be of greater benefit that they really are. The current review documents differences among the studies in terms of vitamin C status of participants. Overall, there is a large body of evidence that maintaining healthy vitamin C levels can have a protective function against age-related cognitive decline and Alzheimer’s disease, but avoiding vitamin C deficiency is likely to be more beneficial than taking supplements on top of a normal, healthy diet. PMID:22366772

  1. The effectiveness of unitization in mitigating age-related relational learning impairments depends on existing cognitive status

    PubMed Central

    D’Angelo, Maria C.; Smith, Victoria M.; Kacollja, Arber; Zhang, Felicia; Binns, Malcolm A.; Barense, Morgan D.; Ryan, Jennifer D.

    2016-01-01

    ABSTRACT Binding relations among items in the transverse patterning (TP) task is dependent on the integrity of the hippocampus and its extended network. Older adults have impaired TP learning, corresponding to age-related reductions in hippocampal volumes. Unitization is a training strategy that can mitigate TP impairments in amnesia by reducing reliance on hippocampal-dependent relational binding and increasing reliance on fused representations. Here we examined whether healthy older adults and those showing early signs of cognitive decline would also benefit from unitization. Although both groups of older adults had neuropsychological performance within the healthy range, their TP learning differed both under standard and unitized training conditions. Healthy older adults with impaired TP learning under standard training benefited from unitized training. Older adults who failed the Montreal Cognitive Assessment (MoCA) showed greater impairments under standard conditions, and showed no evidence of improvement with unitization. These individuals’ failures to benefit from unitization may be a consequence of early deficits not seen in older adults who pass the MoCA. PMID:27049878

  2. The effectiveness of unitization in mitigating age-related relational learning impairments depends on existing cognitive status.

    PubMed

    D'Angelo, Maria C; Smith, Victoria M; Kacollja, Arber; Zhang, Felicia; Binns, Malcolm A; Barense, Morgan D; Ryan, Jennifer D

    2016-11-01

    Binding relations among items in the transverse patterning (TP) task is dependent on the integrity of the hippocampus and its extended network. Older adults have impaired TP learning, corresponding to age-related reductions in hippocampal volumes. Unitization is a training strategy that can mitigate TP impairments in amnesia by reducing reliance on hippocampal-dependent relational binding and increasing reliance on fused representations. Here we examined whether healthy older adults and those showing early signs of cognitive decline would also benefit from unitization. Although both groups of older adults had neuropsychological performance within the healthy range, their TP learning differed both under standard and unitized training conditions. Healthy older adults with impaired TP learning under standard training benefited from unitized training. Older adults who failed the Montreal Cognitive Assessment (MoCA) showed greater impairments under standard conditions, and showed no evidence of improvement with unitization. These individuals' failures to benefit from unitization may be a consequence of early deficits not seen in older adults who pass the MoCA.

  3. Age-related changes in biomechanical properties of the Achilles tendon in rabbits.

    PubMed

    Nakagawa, Y; Hayashi, K; Yamamoto, N; Nagashima, K

    1996-01-01

    We investigated age-related changes in the mechanical properties of rabbit Achilles tendon. The animals used were immature (age 3 weeks, body mass 380 g), young adult (age 8-10 months, body mass 4.1 kg) and old (age 4-5 years, body mass 5.1 kg) rabbits. The cross-sectional area of the tendon increased with growth and the tensile strength of the young adult [67.3 (SEM 4.2) MPa] and old [66.7 (SEM 3.8) MPa] tendon was significantly higher than that of the immature tendon [23.9 (SEM 3.8) MPa]. However, there was no statistically significant difference in tensile strength between mature and old tendons. These differences may be attributable to the change in body mass. The gradient of the stress-strain curves, that is, the tangent modulus of the mature tendon [618.0 (SEM 87.0) MPa], was higher than that of the immature [281.0 (SEM 104.6) MPa] and old [530.5 (SEM 91.0) MPa] tendon, although the difference was not significant. The elongation at failure was approximately 16 percent for all age groups. These results would suggest that rabbit Achilles tendon is highly compliant during growth.

  4. Age-related changes in human vestibulo-ocular reflexes: Sinusoidal rotation and caloric tests

    NASA Technical Reports Server (NTRS)

    Peterka, R. J.; Black, F. O.; Schoenhoff, M. B.

    1989-01-01

    The dynamic response properties of horizontal vestibulo-ocular reflex (VOR) were characterized in 216 human subjects ranging in age from 7 to 81 years. The object of this cross-sectional study was to determine the effects of aging on VOR dynamics, and to identify the distributions of parameters which describe VOR responses to caloric and to sinusoidal rotational stimuli in a putatively normal population. Caloric test parameters showed no consistent trend with age. Rotation test parameters showed declining response amplitude and slightly less compensatory response phase with increasing age. The magnitudes of these changes were not large relative to the variability within the population. The age-related trends in VOR were not consistent with the anatomic changes in the periphery reported by others which showed an increasing rate of peripheral hair cell and nerve fiber loss in subjects over 55 years. The poor correlation between physiological and anatomical data suggest that adaptive mechanisms in the central nervous system are important in maintaining the VOR.

  5. Age-related changes of dental pulp tissue after experimental tooth movement in rats

    PubMed Central

    Von Böhl, Martina; Ren, Yijin; Kuijpers-Jagtman, Anne M.; Maltha, Jaap C.

    2016-01-01

    It is generally accepted that the effect of orthodontic tooth movement on the dental pulp in adolescents is reversible and that it has no long-lasting effect on pulpal physiology. However, it is not clear yet if the same conclusion is also valid for adult subjects. Thus, in two groups of rats, aged 6 and 40 weeks respectively, 3 molars at one side of the maxilla were moved together in a mesial direction with a standardized orthodontic appliance delivering a force of 10 cN. The contralateral side served as a control. Parasagittal histological sections were prepared after tooth movement for 1, 2, 4, 8, and 12 weeks. The pulp tissue was characterized for the different groups, with special emphasis on cell density, inflammatory cells, vascularity, and odontoblasts. Dimensions of dentin and the pulpal horns was determined and related with the duration of orthodontic force application and age ware evaluated. We found that neither in young nor in adult rats, force application led to long-lasting or irreversible changes in pulpal tissues. Dimensional variables showed significant age-related changes. In conclusion, orthodontic tooth movement per se has no long-lasting or irreversible effect on pulpal tissues, neither in the young nor in the adult animals. PMID:26855867

  6. Age-related changes in bone-strength-associated geometry indices in naive human population.

    PubMed

    Kalichman, Leonid; Malkin, Ida; Bigman, Galya; Matias, Rakefet; Seibel, Markus J; Kobyliansky, Eugene; Livshits, Gregory

    2008-07-01

    The aim of the present study was to evaluate age- and sex-related changes in the geometry parameters (metacarpal cortical index (MCI) and Breaking Bending Resistance Index [BBRI]) of long hand bones in a large Chuvashian cohort using cross-sectional and longitudinal study designs. The data were gathered in 1994 (557 individuals) and 2002 (513 individuals). The latter sample included 260 individuals who were studied only during the second expedition, and 253 individuals who were previously investigated in 1994. Statistical analyses included a maximum likelihood-based model-fitting technique and a t-test comparison. Our study describes age-related MCI and BBRI changes in both sexes from the age of 18 years to 84 years. At any age, the BBRI values were higher in males than in females, but MCI was greater in females than in males before age 50 and lower after that age. The study provides initial evidence of a secular trend in MCI and BBRI. In male hand bones, the cortex became relatively thicker and it better resisted bending and breaking in comparison to individuals born at the beginning of the 20th century. In females, the trend toward higher MCI values can be observed only in those born between 1936 and 1966 and the trend toward higher BBRI values stopped in 1950.

  7. Change in contrast sensitivity functions with Corning CPF filters in patients with age related macular degeneration

    NASA Astrophysics Data System (ADS)

    Rimbergas, Sylvia; Raghuram, Aparna; Boothroyd, Gané; Vatianou, Angelo; Lakshminarayanan, Vasudevan; Stelmack, Joan; Stelmack, Thomas

    2005-09-01

    Do Corning CPF filters change contrast sensitivity in patients with age related macular degeneration (AMD)? A retrospective review was conducted of 54 charts of veterans with AMD receiving comprehensive low vision services at VICTORS (VA Chicago West Side). CSF measurements with the VISTECH 6500 test system were compared before and after introduction of Corning CPF filters. Veterans were asked if filters made a noticeable change in contrast. Pre/post-filter CSF data was obtained for 63 trials at 1?m test distance and 60 trials at the 3?m test distance. To evaluate the data we used an analytic function to fit the contrast sensitivity data previously described by Lakshminarayanan [Optom. Vis. Sci. 72 511 (1995)]. An index was used to compare pre- and post-filter information. Veterans were prescribed filters if improvement in contrast was noted, or a subjective improvement was made. Patients were then contacted post-filter during this retrospective study to determine if the filters still enhanced daily activities. Mean improvement in the contrast sensitivity for each spatial frequency ranged from +0.344 to +0.422 patches with the filters at 1?m and +0.183 to +0.548 patches at 3?m. 87.5% of patients reported improvement in contrast while performing activities of daily living with Corning filters. Paired t test are t = -3.8298 (p?=?0.003) at 1?m and t = -4.957 (p = 0.000 01) at 3?m test distance. While the changes in the CSF with filters are statistically significant and consistent with report of self-improvement by patients, the change in the number of patches on the VISTECH 6500 chart is not clinically significant. Clinical implications are that the chart in its current format is not useful for the prescription of filters leaving patient perception of change as a better guideline.

  8. Religiosity is negatively associated with later-life intelligence, but not with age-related cognitive decline.

    PubMed

    Ritchie, Stuart J; Gow, Alan J; Deary, Ian J

    2014-09-01

    A well-replicated finding in the psychological literature is the negative correlation between religiosity and intelligence. However, several studies also conclude that one form of religiosity, church attendance, is protective against later-life cognitive decline. No effects of religious belief per se on cognitive decline have been found, potentially due to the restricted measures of belief used in previous studies. Here, we examined the associations between religiosity, intelligence, and cognitive change in a cohort of individuals (initial n = 550) with high-quality measures of religious belief taken at age 83 and multiple cognitive measures taken in childhood and at four waves between age 79 and 90. We found that religious belief, but not attendance, was negatively related to intelligence. The effect size was smaller than in previous studies of younger participants. Longitudinal analyses showed no effect of either religious belief or attendance on cognitive change either from childhood to old age, or across the ninth decade of life. We discuss differences between our cohort and those in previous studies - including in age and location - that may have led to our non-replication of the association between religious attendance and cognitive decline.

  9. Age-related changes in mesenchymal stem cells identified using a multi-omics approach.

    PubMed

    Peffers, M J; Collins, J; Fang, Y; Goljanek-Whysall, K; Rushton, M; Loughlin, J; Proctor, C; Clegg, P D

    2016-01-01

    Mesenchymal stem cells (MSC) are capable of multipotent differentiation into connective tissues and as such are an attractive source for autologous cell-based treatments for many clinical diseases and injuries. Ageing is associated with various altered cellular phenotypes coupled with a variety of transcriptional, epigenetic and translational changes. Furthermore, the regeneration potential of MSCs is reduced with increasing age and is correlated with changes in cellular functions. This study used a systems biology approach to investigate the transcriptomic (RNASeq), epigenetic (miRNASeq and DNA methylation) and protein alterations in ageing MSCs in order to understand the age-related functional and biological variations, which may affect their applications to regenerative medicine. We identified no change in expression of the cellular senescence markers. Alterations were evident at both the transcriptional and post-transcriptional level in a number of transcription factors. There was enrichment in genes involved in developmental disorders at mRNA and differential methylated loci (DML) level. Alterations in energy metabolism were apparent at the DML and protein level. The microRNA miR-199b-5p, whose expression was reduced in old MSCs, had predicted gene targets involved in energy metabolism and cell survival. Additionally, enrichment of DML and proteins in cell survival was evident. Enrichment in metabolic processes was revealed at the protein level and in genes identified as undergoing alternate splicing. Overall, an altered phenotype in MSC ageing at a number of levels implicated roles for inflamm-ageing and mitochondrial ageing. Identified changes represent novel insights into the ageing process, with implications for stem cell therapies in older patients. PMID:26853623

  10. Age-related changes in conjunctive visual search in children with and without ASD.

    PubMed

    Iarocci, Grace; Armstrong, Kimberly

    2014-04-01

    Visual-spatial strengths observed among people with autism spectrum disorder (ASD) may be associated with increased efficiency of selective attention mechanisms such as visual search. In a series of studies, researchers examined the visual search of targets that share features with distractors in a visual array and concluded that people with ASD showed enhanced performance on visual search tasks. However, methodological limitations, the small sample sizes, and the lack of developmental analysis have tempered the interpretations of these results. In this study, we specifically addressed age-related changes in visual search. We examined conjunctive visual search in groups of children with (n = 34) and without ASD (n = 35) at 7-9 years of age when visual search performance is beginning to improve, and later, at 10-12 years, when performance has improved. The results were consistent with previous developmental findings; 10- to 12-year-old children were significantly faster visual searchers than their 7- to 9-year-old counterparts. However, we found no evidence of enhanced search performance among the children with ASD at either the younger or older ages. More research is needed to understand the development of visual search in both children with and without ASD.

  11. Age-Related Changes Between the Level of Velopharyngeal Closure and the Cervical Spine.

    PubMed

    Mason, Kazlin N; Perry, Jamie L; Riski, John E; Fang, Xiangming

    2016-03-01

    The primary focus of this study was to assess age-related changes in the vertical distance of the estimated level of velopharyngeal closure in relation to a prominent landmark of the cervical spine: the anterior tubercle of cervical vertebra 1 (C1). Midsagittal anatomic magnetic resonance images were examined across 51 participants with normal head and neck anatomy between 4 and 17 years of age. Results indicate that age is a strong predictor (P = 0.002) of the vertical distance between the level of velopharyngeal closure relative to C1. Specifically, as age increases, the vertical distance between the palatal plane and C1 becomes greater resulting in the level of velopharyngeal closure being located higher above C1 (range 4.88-10.55 mm). Results of this study provide insights into the clinical usefulness of using C1 as a surgical landmark for placement of pharyngoplasties in children with repaired cleft palate and persistent hypernasal speech. Clinical implications and future directions are discussed.

  12. Children's recognition of fairness and others' welfare in a resource allocation task: Age related changes.

    PubMed

    Rizzo, Michael T; Elenbaas, Laura; Cooley, Shelby; Killen, Melanie

    2016-08-01

    The present study investigated age-related changes regarding children's (N = 136) conceptions of fairness and others' welfare in a merit-based resource allocation paradigm. To test whether children at 3- to 5-years-old and 6- to 8-years-old took others' welfare into account when dividing resources, in addition to merit and equality concerns, children were asked to allocate, judge, and reason about allocations of necessary (needed to avoid harm) and luxury (enjoyable to have) resources to a hardworking and a lazy character. While 3- to 5-year-olds did not differentiate between distributing luxury and necessary resources, 6- to 8-year-olds allocated luxury resources more meritoriously than necessary resources. Further, children based their allocations of necessary resources on concerns for others' welfare, rather than merit, even when one character was described as working harder. The findings revealed that, with age, children incorporated the concerns for others' welfare and merit into their conceptions of fairness in a resource allocation context, and prioritized these concerns differently depending on whether they were allocating luxury or necessary resources. Further, with age, children weighed multiple moral concerns including equality, merit, and others' welfare, when determining the fair allocation of resources. (PsycINFO Database Record PMID:27455189

  13. Age related changes and osteochondrosis in swine articular and epiphyseal cartilage: light ane electron microscopy.

    PubMed Central

    Bhatnagar, R; Christian, R G; Nakano, T; Aherne, F X; Thompson, J R

    1981-01-01

    Age related changes and osteochondrosis in swine were studied using light microscopy and electron microscopy in articular cartilage and light microscopy and epiphyseal cartilage of swine from three days to 30 weeks of age. Thickness, cellularity and vascularity of both the epiphyseal and articular cartilage, decreased as the swine aged. Osteochondrotic changes included formation of "plugs" of cartilage indicating localized failure of ossification and separation and space formation in epiphyseal cartilage. Eosinophilic streaks and space formation in epiphyseal cartilage was observed in relation to epiphyseal separation. Electron microscopy showed a continuous fibrillar layer on the surface of the cartilage corresponding to the lamina splendens of light microscopy. This layer increased in the thickness and showed accumulation of amorphous material between the fibrils with aging. In the matrix, the orientation and distribution of the collagen fibers changed with growth and thicker fibers with clear sub banding were more common in older age groups. Also, necrotic cells, glycogen containing bodies and cellular debris were noticed in the matrix of normal cartilage in old animals. Chondrocytes in the younger cartilage showed accumulation of organelles responsible for protein synthesis; while Golgi bodies, vesicles, lysosomes, well developed foot processes and other inclusions were noticed in older cartilage. Cartilage erosions had a clumped and disrupted lamina splendens on the surface and electron lucent patches in the ground substances of the matrix and chondrocyte cytoplasm. Images Fig. 1. Fig. 2 and 3. Fig. 4. Fig. 5. Fig. 6. Fig. 7. Fig. 8. Fig. 9. Fig. 10 and 11. Fig. 12. Fig. 13. Fig. 14. Fig. 15. Fig. 16. Fig. 17. Fig. 18. PMID:7260732

  14. Age-related gene expression change of GABAergic system in visual cortex of rhesus macaque.

    PubMed

    Liao, Chenghong; Han, Qian; Ma, Yuanye; Su, Bing

    2016-09-30

    Degradation of visual function is a common phenomenon during aging and likely mediated by change in the impaired central visual pathway. Treatment with GABA or its agonist could recover the ability of visual neurons in the primary visual cortex of senescent macaques. However, little is known about how GABAergic system change is related to the aged degradation of visual function in nonhuman primate. With the use of quantitative PCR method, we measured the expression change of 24 GABA related genes in the primary visual cortex (Brodmann's 17) of different age groups. In this study, both of mRNA and protein of glutamic acid decarboxylase (GAD65) were measured by real-time RT-PCR and Western blot, respectively. Results revealed that the level of GAD65 message was not significantly altered, but the proteins were significantly decreased in the aged monkey. As GAD65 plays an important role in GABA synthesis, the down-regulation of GAD65 protein was likely the key factor leading to the observed GABA reduction in the primary visual cortex of the aged macaques. In addition, 7 of 14 GABA receptor genes were up-regulated and one GABA receptor gene was significantly reduced during aging process even after Banjamini correction for multiple comparisons (P<0.05). These results suggested that the dysregulation of GAD65 protein might contribute to some age-related neural visual dysfunctions and most of GABA receptor genes induce a clear indication of compensatory effect for the reduced GABA release in the healthy aged monkey cortex. PMID:27196061

  15. High Resolution Topography of Age-Related Changes in Non-Rapid Eye Movement Sleep Electroencephalography.

    PubMed

    Sprecher, Kate E; Riedner, Brady A; Smith, Richard F; Tononi, Giulio; Davidson, Richard J; Benca, Ruth M

    2016-01-01

    Sleeping brain activity reflects brain anatomy and physiology. The aim of this study was to use high density (256 channel) electroencephalography (EEG) during sleep to characterize topographic changes in sleep EEG power across normal aging, with high spatial resolution. Sleep was evaluated in 92 healthy adults aged 18-65 years old using full polysomnography and high density EEG. After artifact removal, spectral power density was calculated for standard frequency bands for all channels, averaged across the NREM periods of the first 3 sleep cycles. To quantify topographic changes with age, maps were generated of the Pearson's coefficient of the correlation between power and age at each electrode. Significant correlations were determined by statistical non-parametric mapping. Absolute slow wave power declined significantly with increasing age across the entire scalp, whereas declines in theta and sigma power were significant only in frontal regions. Power in fast spindle frequencies declined significantly with increasing age frontally, whereas absolute power of slow spindle frequencies showed no significant change with age. When EEG power was normalized across the scalp, a left centro-parietal region showed significantly less age-related decline in power than the rest of the scalp. This partial preservation was particularly significant in the slow wave and sigma bands. The effect of age on sleep EEG varies substantially by region and frequency band. This non-uniformity should inform the design of future investigations of aging and sleep. This study provides normative data on the effect of age on sleep EEG topography, and provides a basis from which to explore the mechanisms of normal aging as well as neurodegenerative disorders for which age is a risk factor.

  16. High Resolution Topography of Age-Related Changes in Non-Rapid Eye Movement Sleep Electroencephalography

    PubMed Central

    Sprecher, Kate E.; Riedner, Brady A.; Smith, Richard F.; Tononi, Giulio; Davidson, Richard J.; Benca, Ruth M.

    2016-01-01

    Sleeping brain activity reflects brain anatomy and physiology. The aim of this study was to use high density (256 channel) electroencephalography (EEG) during sleep to characterize topographic changes in sleep EEG power across normal aging, with high spatial resolution. Sleep was evaluated in 92 healthy adults aged 18–65 years old using full polysomnography and high density EEG. After artifact removal, spectral power density was calculated for standard frequency bands for all channels, averaged across the NREM periods of the first 3 sleep cycles. To quantify topographic changes with age, maps were generated of the Pearson’s coefficient of the correlation between power and age at each electrode. Significant correlations were determined by statistical non-parametric mapping. Absolute slow wave power declined significantly with increasing age across the entire scalp, whereas declines in theta and sigma power were significant only in frontal regions. Power in fast spindle frequencies declined significantly with increasing age frontally, whereas absolute power of slow spindle frequencies showed no significant change with age. When EEG power was normalized across the scalp, a left centro-parietal region showed significantly less age-related decline in power than the rest of the scalp. This partial preservation was particularly significant in the slow wave and sigma bands. The effect of age on sleep EEG varies substantially by region and frequency band. This non-uniformity should inform the design of future investigations of aging and sleep. This study provides normative data on the effect of age on sleep EEG topography, and provides a basis from which to explore the mechanisms of normal aging as well as neurodegenerative disorders for which age is a risk factor. PMID:26901503

  17. [The Influence of the Functional State of Brain Regulatory Structures on the Programming, Selective Regulation and Control of Cognitive Activity in Children. Report I: Neuropsychological and EEG Analysis of Age-Related Changes in Brain Regulatory Functions in Children Aged 9-12 Years].

    PubMed

    Semenova, A; Machinskaya, R I; Lomakin, D I

    2015-01-01

    Age-related changes in brain regulatory functions in children aged from 9 to 12 years with typical development were studied by means of neuropsychological and EEG analysis. The participants of the study were 107 children without learning difficulties and behavior deviations; they were devided into three groups (9-10, 10-11 and 11-12 years). The neuropsychological tests revealed nonlinear age-related changes in different executive brain functions. The group of 10-11-year-old children showed better results in programming, in- hibition of impulsive reactions and in the perception of socially relevant information than the group of 9-10- year-old children. At the same time, these children had more difficulties with selective activity regulation as compared with the younger group. The difficulties were mainly caused by switching from one element of the program to another and by retention of learned sequence of actions. These children also showed a lower level of motivation for task performance. The children aged 11-12 years had less difficulties with selective activity regulation; however, impulsive behavior was more frequent; these children also had a higher level of task performance motivation than in children aged 10-11 years. The analysis of resting state EEG revealed age-related differences in deviated EEG patterns associated with non-optimal functioning of fronto-thalamic system and hypothalamic structures. The incidence of these two types of EEG patterns was significantly higher in children aged 10-11 years as compared with children aged 9-10 years. The EEG of the groups of 10-11 and 11-12-years-old children did not show any significant differences. PMID:26485784

  18. [The Influence of the Functional State of Brain Regulatory Structures on the Programming, Selective Regulation and Control of Cognitive Activity in Children. Report I: Neuropsychological and EEG Analysis of Age-Related Changes in Brain Regulatory Functions in Children Aged 9-12 Years].

    PubMed

    Semenova, A; Machinskaya, R I; Lomakin, D I

    2015-01-01

    Age-related changes in brain regulatory functions in children aged from 9 to 12 years with typical development were studied by means of neuropsychological and EEG analysis. The participants of the study were 107 children without learning difficulties and behavior deviations; they were devided into three groups (9-10, 10-11 and 11-12 years). The neuropsychological tests revealed nonlinear age-related changes in different executive brain functions. The group of 10-11-year-old children showed better results in programming, in- hibition of impulsive reactions and in the perception of socially relevant information than the group of 9-10- year-old children. At the same time, these children had more difficulties with selective activity regulation as compared with the younger group. The difficulties were mainly caused by switching from one element of the program to another and by retention of learned sequence of actions. These children also showed a lower level of motivation for task performance. The children aged 11-12 years had less difficulties with selective activity regulation; however, impulsive behavior was more frequent; these children also had a higher level of task performance motivation than in children aged 10-11 years. The analysis of resting state EEG revealed age-related differences in deviated EEG patterns associated with non-optimal functioning of fronto-thalamic system and hypothalamic structures. The incidence of these two types of EEG patterns was significantly higher in children aged 10-11 years as compared with children aged 9-10 years. The EEG of the groups of 10-11 and 11-12-years-old children did not show any significant differences.

  19. Age-related changes in urinary testosterone levels suggest differences in puberty onset and divergent life history strategies in bonobos and chimpanzees.

    PubMed

    Behringer, V; Deschner, T; Deimel, C; Stevens, J M G; Hohmann, G

    2014-08-01

    Research on age-related changes in morphology, social behavior, and cognition suggests that the development of bonobos (Pan paniscus) is delayed in comparison to chimpanzees (Pan troglodytes). However, there is also evidence for earlier reproductive maturation in bonobos. Since developmental changes such as reproductive maturation are induced by a number of endocrine processes, changes in hormone levels are indicators of different developmental stages. Age-related changes in testosterone excretion are an indirect marker for the onset of puberty in human and non-human primates. In this study we investigated patterns of urinary testosterone levels in male and female bonobos and chimpanzees to determine the onset of puberty. In contrast to other studies, we found that both species experience age-related changes in urinary testosterone levels. Older individuals of both sexes had significantly higher urinary testosterone levels than younger individuals, indicating that bonobos and chimpanzees experience juvenile pause. The males of both species showed a similar pattern of age-related changes in urinary testosterone levels, with a sharp increase in levels around the age of eight years. This suggests that species-differences in aggression and male mate competition evolved independently of developmental changes in testosterone levels. Females showed a similar pattern of age-related urinary testosterone increase. However, in female bonobos the onset was about three years earlier than in female chimpanzees. The earlier rise of urinary testosterone levels in female bonobos is in line with reports of their younger age of dispersal, and suggests that female bonobos experience puberty at a younger age than female chimpanzees. PMID:25086337

  20. Age-related changes in urinary testosterone levels suggest differences in puberty onset and divergent life history strategies in bonobos and chimpanzees.

    PubMed

    Behringer, V; Deschner, T; Deimel, C; Stevens, J M G; Hohmann, G

    2014-08-01

    Research on age-related changes in morphology, social behavior, and cognition suggests that the development of bonobos (Pan paniscus) is delayed in comparison to chimpanzees (Pan troglodytes). However, there is also evidence for earlier reproductive maturation in bonobos. Since developmental changes such as reproductive maturation are induced by a number of endocrine processes, changes in hormone levels are indicators of different developmental stages. Age-related changes in testosterone excretion are an indirect marker for the onset of puberty in human and non-human primates. In this study we investigated patterns of urinary testosterone levels in male and female bonobos and chimpanzees to determine the onset of puberty. In contrast to other studies, we found that both species experience age-related changes in urinary testosterone levels. Older individuals of both sexes had significantly higher urinary testosterone levels than younger individuals, indicating that bonobos and chimpanzees experience juvenile pause. The males of both species showed a similar pattern of age-related changes in urinary testosterone levels, with a sharp increase in levels around the age of eight years. This suggests that species-differences in aggression and male mate competition evolved independently of developmental changes in testosterone levels. Females showed a similar pattern of age-related urinary testosterone increase. However, in female bonobos the onset was about three years earlier than in female chimpanzees. The earlier rise of urinary testosterone levels in female bonobos is in line with reports of their younger age of dispersal, and suggests that female bonobos experience puberty at a younger age than female chimpanzees.

  1. Age-related functional changes of the glutamate receptor channels in rat Meynert neurones.

    PubMed Central

    Akaike, N; Rhee, J S

    1997-01-01

    -phosphonopentanoic acid (APV) in the 1D rat neurones than in the adult rat neurones. 7. Both NMDA and KA raised the intracellular Ca2+ concentration ([Ca2+]i) in all neurones of 1D, 2W and 6M rats, though the charybdotoxin-sensitive Ca(2+)-activated K+ current (IK(Ca)) did not appear in the 1D rat neurones. An age-related prolongation of both IK(Ca) decay and [Ca2+]i clearance was also seen after the removal of KA. 8. It was thus concluded that the age-related changes of ionotropic receptors appear to play a key role in the activities of immature and mature rat Meynert cholinergic neurones. The KA-induced IK(Ca), which developed with ageing, may thus function as one of the negative feedback systems, and thereby prevent excess cell excitation and neural damage, especially in adult rats. PMID:9401973

  2. [Primary age-related tauopathy (PART): a novel term to describe age-related tangle pathology encompassing a wide range from cognitively normal condition to senile dementia of the neurofibrillary tangle type].

    PubMed

    Yamada, Masahito

    2016-03-01

    It has been reported that neurofibrillary tangles (NFTs) are commonly observed in older people, and that some of older individuals with dementia have a large amount of NFTs in the medial temporal lobe without amyloid(Aβ) plaques, which have been referred to as senile dementia of the NFT type (SD-NFT), tangle-predominant senile dementia (TPSD), or tangle-only dementia. In 2014, our international collaborative group proposed a new term, "primary age-related tauopathy(PART)", to describe such age-related tangle pathology, clinically encompassing a wide range from normal to cognitive impairment/ dementia (SD-NFT). This nomenclature would provide a conceptual foundation for future studies leading to development of clinical diagnosis for this condition. PMID:27025089

  3. Age-related changes in intraventricular kinetic energy: a physiological or pathological adaptation?

    PubMed

    Wong, James; Chabiniok, Radomir; deVecchi, Adelaide; Dedieu, Nathalie; Sammut, Eva; Schaeffter, Tobias; Razavi, Reza

    2016-03-15

    Aging has important deleterious effects on the cardiovascular system. We sought to compare intraventricular kinetic energy (KE) in healthy subjects of varying ages with subjects with ventricular dysfunction to understand if changes in energetic momentum may predispose individuals to heart failure. Four-dimensional flow MRI was acquired in 35 healthy subjects (age: 1-67 yr) and 10 patients with left ventricular (LV) dysfunction (age: 28-79 yr). Healthy subjects were divided into age quartiles (1st quartile: <16 yr, 2nd quartile: 17-32 yr, 3rd quartile: 33-48 yr, and 4th quartile: 49-64 yr). KE was measured in the LV throughout the cardiac cycle and indexed to ventricular volume. In healthy subjects, two large peaks corresponding to systole and early diastole occurred during the cardiac cycle. A third smaller peak was seen during late diastole in eight adults. Systolic KE (P = 0.182) and ejection fraction (P = 0.921) were preserved through all age groups. Older adults showed a lower early peak diastolic KE compared with children (P < 0.0001) and young adults (P = 0.025). Subjects with LV dysfunction had reduced ejection fraction (P < 0.001) and compared with older healthy adults exhibited a similar early peak diastolic KE (P = 0.142) but with the addition of an elevated KE in diastasis (P = 0.029). In healthy individuals, peak diastolic KE progressively decreases with age, whereas systolic peaks remain constant. Peak diastolic KE in the oldest subjects is comparable to those with LV dysfunction. Unique age-related changes in ventricular diastolic energetics might be physiological or herald subclinical pathology.

  4. Age-Related Changes in Children’s Associations of Economic Resources and Race

    PubMed Central

    Elenbaas, Laura; Killen, Melanie

    2016-01-01

    Age-related changes in children’s associations of economic resources and race were investigated. The sample (N = 308) included 5–6 year-olds (n = 153, M = 6.01 years, SD = 0.33 years) and 10–11 year-olds (n = 155, M = 11.12 years, SD = 0.59 years) of African–American (n = 93), European–American (n = 92), Latino (n = 62), Asian–American (n = 23), and multi-racial or multi-ethnic (n = 26) background. Participants matched pairs of target children (African–American and European–American) with visual indicators of low, middle, and high economic status. Children’s associations of economic resources with racial groups changed with age, and reflected different associations at high, middle, and low levels of the economic spectrum. Specifically, children associated targets of both races with middle economic status at a comparable rate, and with age, increasingly associated targets of both races with indicators of middle economic status. By contrast, both younger and older children associated African–American targets with indicators of low economic status more frequently than European–American targets. Finally, children associated African–American targets with indicators of high economic status less frequently with age, resulting in a perceived disparity in favor of European–American targets at high economic status among older children that was not present among younger children. No differences were found by participants’ own racial or ethnic background. These results highlight the need to move beyond a dichotomized view (rich or poor) to include middle economic status when examining children’s associations of economic resources and race. PMID:27378981

  5. Age-related changes in intraventricular kinetic energy: a physiological or pathological adaptation?

    PubMed Central

    Wong, James; Chabiniok, Radomir; deVecchi, Adelaide; Dedieu, Nathalie; Sammut, Eva; Schaeffter, Tobias

    2016-01-01

    Aging has important deleterious effects on the cardiovascular system. We sought to compare intraventricular kinetic energy (KE) in healthy subjects of varying ages with subjects with ventricular dysfunction to understand if changes in energetic momentum may predispose individuals to heart failure. Four-dimensional flow MRI was acquired in 35 healthy subjects (age: 1–67 yr) and 10 patients with left ventricular (LV) dysfunction (age: 28–79 yr). Healthy subjects were divided into age quartiles (1st quartile: <16 yr, 2nd quartile: 17–32 yr, 3rd quartile: 33–48 yr, and 4th quartile: 49–64 yr). KE was measured in the LV throughout the cardiac cycle and indexed to ventricular volume. In healthy subjects, two large peaks corresponding to systole and early diastole occurred during the cardiac cycle. A third smaller peak was seen during late diastole in eight adults. Systolic KE (P = 0.182) and ejection fraction (P = 0.921) were preserved through all age groups. Older adults showed a lower early peak diastolic KE compared with children (P < 0.0001) and young adults (P = 0.025). Subjects with LV dysfunction had reduced ejection fraction (P < 0.001) and compared with older healthy adults exhibited a similar early peak diastolic KE (P = 0.142) but with the addition of an elevated KE in diastasis (P = 0.029). In healthy individuals, peak diastolic KE progressively decreases with age, whereas systolic peaks remain constant. Peak diastolic KE in the oldest subjects is comparable to those with LV dysfunction. Unique age-related changes in ventricular diastolic energetics might be physiological or herald subclinical pathology. PMID:26747496

  6. Age-Related Changes in Children's Associations of Economic Resources and Race.

    PubMed

    Elenbaas, Laura; Killen, Melanie

    2016-01-01

    Age-related changes in children's associations of economic resources and race were investigated. The sample (N = 308) included 5-6 year-olds (n = 153, M = 6.01 years, SD = 0.33 years) and 10-11 year-olds (n = 155, M = 11.12 years, SD = 0.59 years) of African-American (n = 93), European-American (n = 92), Latino (n = 62), Asian-American (n = 23), and multi-racial or multi-ethnic (n = 26) background. Participants matched pairs of target children (African-American and European-American) with visual indicators of low, middle, and high economic status. Children's associations of economic resources with racial groups changed with age, and reflected different associations at high, middle, and low levels of the economic spectrum. Specifically, children associated targets of both races with middle economic status at a comparable rate, and with age, increasingly associated targets of both races with indicators of middle economic status. By contrast, both younger and older children associated African-American targets with indicators of low economic status more frequently than European-American targets. Finally, children associated African-American targets with indicators of high economic status less frequently with age, resulting in a perceived disparity in favor of European-American targets at high economic status among older children that was not present among younger children. No differences were found by participants' own racial or ethnic background. These results highlight the need to move beyond a dichotomized view (rich or poor) to include middle economic status when examining children's associations of economic resources and race. PMID:27378981

  7. Hearing, Cognition, and Healthy Aging: Social and Public Health Implications of the Links between Age-Related Declines in Hearing and Cognition

    PubMed Central

    Pichora-Fuller, M. Kathleen; Mick, Paul; Reed, Marilyn

    2015-01-01

    Sensory input provides the signals used by the brain when listeners understand speech and participate in social activities with other people in a range of everyday situations. When sensory inputs are diminished, there can be short-term consequences to brain functioning, and long-term deprivation can affect brain neuroplasticity. Indeed, the association between hearing loss and cognitive declines in older adults is supported by experimental and epidemiologic evidence, although the causal mechanisms remain unknown. These interactions of auditory and cognitive aging play out in the challenges confronted by people with age-related hearing problems when understanding speech and engaging in social interactions. In the present article, we use the World Health Organization's International Classification of Functioning, Disability and Health and the Selective Optimization with Compensation models to highlight the importance of adopting a healthy aging perspective that focuses on facilitating active social participation by older adults. First, we examine epidemiologic evidence linking ARHL to cognitive declines and other health issues. Next, we examine how social factors influence and are influenced by auditory and cognitive aging and if they may provide a possible explanation for the association between ARHL and cognitive decline. Finally, we outline how audiologists could reposition hearing health care within the broader context of healthy aging. PMID:27516713

  8. Hearing, Cognition, and Healthy Aging: Social and Public Health Implications of the Links between Age-Related Declines in Hearing and Cognition.

    PubMed

    Pichora-Fuller, M Kathleen; Mick, Paul; Reed, Marilyn

    2015-08-01

    Sensory input provides the signals used by the brain when listeners understand speech and participate in social activities with other people in a range of everyday situations. When sensory inputs are diminished, there can be short-term consequences to brain functioning, and long-term deprivation can affect brain neuroplasticity. Indeed, the association between hearing loss and cognitive declines in older adults is supported by experimental and epidemiologic evidence, although the causal mechanisms remain unknown. These interactions of auditory and cognitive aging play out in the challenges confronted by people with age-related hearing problems when understanding speech and engaging in social interactions. In the present article, we use the World Health Organization's International Classification of Functioning, Disability and Health and the Selective Optimization with Compensation models to highlight the importance of adopting a healthy aging perspective that focuses on facilitating active social participation by older adults. First, we examine epidemiologic evidence linking ARHL to cognitive declines and other health issues. Next, we examine how social factors influence and are influenced by auditory and cognitive aging and if they may provide a possible explanation for the association between ARHL and cognitive decline. Finally, we outline how audiologists could reposition hearing health care within the broader context of healthy aging. PMID:27516713

  9. Hearing, Cognition, and Healthy Aging: Social and Public Health Implications of the Links between Age-Related Declines in Hearing and Cognition.

    PubMed

    Pichora-Fuller, M Kathleen; Mick, Paul; Reed, Marilyn

    2015-08-01

    Sensory input provides the signals used by the brain when listeners understand speech and participate in social activities with other people in a range of everyday situations. When sensory inputs are diminished, there can be short-term consequences to brain functioning, and long-term deprivation can affect brain neuroplasticity. Indeed, the association between hearing loss and cognitive declines in older adults is supported by experimental and epidemiologic evidence, although the causal mechanisms remain unknown. These interactions of auditory and cognitive aging play out in the challenges confronted by people with age-related hearing problems when understanding speech and engaging in social interactions. In the present article, we use the World Health Organization's International Classification of Functioning, Disability and Health and the Selective Optimization with Compensation models to highlight the importance of adopting a healthy aging perspective that focuses on facilitating active social participation by older adults. First, we examine epidemiologic evidence linking ARHL to cognitive declines and other health issues. Next, we examine how social factors influence and are influenced by auditory and cognitive aging and if they may provide a possible explanation for the association between ARHL and cognitive decline. Finally, we outline how audiologists could reposition hearing health care within the broader context of healthy aging.

  10. Age-related striatal BOLD changes without changes in behavioral loss aversion

    PubMed Central

    Viswanathan, Vijay; Lee, Sang; Gilman, Jodi M.; Kim, Byoung Woo; Lee, Nick; Chamberlain, Laura; Livengood, Sherri L.; Raman, Kalyan; Lee, Myung Joo; Kuster, Jake; Stern, Daniel B.; Calder, Bobby; Mulhern, Frank J.; Blood, Anne J.; Breiter, Hans C.

    2015-01-01

    Loss aversion (LA), the idea that negative valuations have a higher psychological impact than positive ones, is considered an important variable in consumer research. The literature on aging and behavior suggests older individuals may show more LA, although it is not clear if this is an effect of aging in general (as in the continuum from age 20 and 50 years), or of the state of older age (e.g., past age 65 years). We also have not yet identified the potential biological effects of aging on the neural processing of LA. In the current study we used a cohort of subjects with a 30 year range of ages, and performed whole brain functional MRI (fMRI) to examine the ventral striatum/nucleus accumbens (VS/NAc) response during a passive viewing of affective faces with model-based fMRI analysis incorporating behavioral data from a validated approach/avoidance task with the same stimuli. Our a priori focus on the VS/NAc was based on (1) the VS/NAc being a central region for reward/aversion processing; (2) its activation to both positive and negative stimuli; (3) its reported involvement with tracking LA. LA from approach/avoidance to affective faces showed excellent fidelity to published measures of LA. Imaging results were then compared to the behavioral measure of LA using the same affective faces. Although there was no relationship between age and LA, we observed increasing neural differential sensitivity (NDS) of the VS/NAc to avoidance responses (negative valuations) relative to approach responses (positive valuations) with increasing age. These findings suggest that a central region for reward/aversion processing changes with age, and may require more activation to produce the same LA behavior as in younger individuals, consistent with the idea of neural efficiency observed with high IQ individuals showing less brain activation to complete the same task. PMID:25983682

  11. Age-related striatal BOLD changes without changes in behavioral loss aversion.

    PubMed

    Viswanathan, Vijay; Lee, Sang; Gilman, Jodi M; Kim, Byoung Woo; Lee, Nick; Chamberlain, Laura; Livengood, Sherri L; Raman, Kalyan; Lee, Myung Joo; Kuster, Jake; Stern, Daniel B; Calder, Bobby; Mulhern, Frank J; Blood, Anne J; Breiter, Hans C

    2015-01-01

    Loss aversion (LA), the idea that negative valuations have a higher psychological impact than positive ones, is considered an important variable in consumer research. The literature on aging and behavior suggests older individuals may show more LA, although it is not clear if this is an effect of aging in general (as in the continuum from age 20 and 50 years), or of the state of older age (e.g., past age 65 years). We also have not yet identified the potential biological effects of aging on the neural processing of LA. In the current study we used a cohort of subjects with a 30 year range of ages, and performed whole brain functional MRI (fMRI) to examine the ventral striatum/nucleus accumbens (VS/NAc) response during a passive viewing of affective faces with model-based fMRI analysis incorporating behavioral data from a validated approach/avoidance task with the same stimuli. Our a priori focus on the VS/NAc was based on (1) the VS/NAc being a central region for reward/aversion processing; (2) its activation to both positive and negative stimuli; (3) its reported involvement with tracking LA. LA from approach/avoidance to affective faces showed excellent fidelity to published measures of LA. Imaging results were then compared to the behavioral measure of LA using the same affective faces. Although there was no relationship between age and LA, we observed increasing neural differential sensitivity (NDS) of the VS/NAc to avoidance responses (negative valuations) relative to approach responses (positive valuations) with increasing age. These findings suggest that a central region for reward/aversion processing changes with age, and may require more activation to produce the same LA behavior as in younger individuals, consistent with the idea of neural efficiency observed with high IQ individuals showing less brain activation to complete the same task.

  12. Age-related striatal BOLD changes without changes in behavioral loss aversion.

    PubMed

    Viswanathan, Vijay; Lee, Sang; Gilman, Jodi M; Kim, Byoung Woo; Lee, Nick; Chamberlain, Laura; Livengood, Sherri L; Raman, Kalyan; Lee, Myung Joo; Kuster, Jake; Stern, Daniel B; Calder, Bobby; Mulhern, Frank J; Blood, Anne J; Breiter, Hans C

    2015-01-01

    Loss aversion (LA), the idea that negative valuations have a higher psychological impact than positive ones, is considered an important variable in consumer research. The literature on aging and behavior suggests older individuals may show more LA, although it is not clear if this is an effect of aging in general (as in the continuum from age 20 and 50 years), or of the state of older age (e.g., past age 65 years). We also have not yet identified the potential biological effects of aging on the neural processing of LA. In the current study we used a cohort of subjects with a 30 year range of ages, and performed whole brain functional MRI (fMRI) to examine the ventral striatum/nucleus accumbens (VS/NAc) response during a passive viewing of affective faces with model-based fMRI analysis incorporating behavioral data from a validated approach/avoidance task with the same stimuli. Our a priori focus on the VS/NAc was based on (1) the VS/NAc being a central region for reward/aversion processing; (2) its activation to both positive and negative stimuli; (3) its reported involvement with tracking LA. LA from approach/avoidance to affective faces showed excellent fidelity to published measures of LA. Imaging results were then compared to the behavioral measure of LA using the same affective faces. Although there was no relationship between age and LA, we observed increasing neural differential sensitivity (NDS) of the VS/NAc to avoidance responses (negative valuations) relative to approach responses (positive valuations) with increasing age. These findings suggest that a central region for reward/aversion processing changes with age, and may require more activation to produce the same LA behavior as in younger individuals, consistent with the idea of neural efficiency observed with high IQ individuals showing less brain activation to complete the same task. PMID:25983682

  13. Modeling the mechanical behavior of vertebral trabecular bone: effects of age-related changes in microstructure.

    PubMed

    Silva, M J; Gibson, L J

    1997-08-01

    Age-related reductions in the thickness and number of trabeculae in vertebral trabecular bone have been documented by several workers, yet the relative effects of these changes on mechanical properties are not known. We developed a two-dimensional model of human vertebral trabecular bone and investigated its mechanical behavior using finite element analysis. The stress-strain behavior, failure mode, and strain distributions predicted using the model were consistent with those observed for vertebral trabecular bone under compressive loading. Random reductions in the number of trabeculae reduced the modulus and strength of the models two to five times more than uniform reductions in the thickness of trabeculae that caused the same loss of bone volume. For example, randomly removing longitudinal trabeculae to achieve a reduction in density of 10% reduced the strength by approximately 70%, whereas removing the same amount of bone by uniformly reducing the thickness of the longitudinal trabeculae only reduced the strength by approximately 20%. For a simulation of aged bone, in which the thickness and number of trabeculae were reduced concurrently, the strength was 23% of its intact ("young") value. When the bone mass of the aged model was restored to its intact level by increasing the thickness but not the number of trabeculae, the strength increased by 60%, but was still only 37% of its intact value. These combined findings, based on a two-dimensional, idealized model of vertebral trabecular bone, illustrate the importance of maintaining trabecular number and suggest that it may not be possible to restore bone strength following a period of advanced bone loss if a substantial number of trabeculae have been resorbed. Thus, until treatments exist that can increase trabecular number, the most effective treatment strategy is to prevent the degradation of bone strength by maintaining the number of trabeculae at a healthy level.

  14. Glaucomatous and Age-Related Changes in Corneal Pulsation Shape. The Ocular Dicrotism

    PubMed Central

    Danielewska, Monika E.; Krzyżanowska-Berkowska, Patrycja; Iskander, D. Robert

    2014-01-01

    Purpose To ascertain whether the incidence of ocular dicrotic pulse (ODP) increases with age, it is more pronounced in glaucomatous than in normal eyes and whether it is related to cardiovascular activity. Methods 261 subjects aged 47 to 78 years were included in the study and classified into four groups: primary open angle glaucoma (POAG), primary angle-closure glaucoma (PACG), glaucoma suspects with glaucomatous optic disc appearance (GODA) and the controls (CG). Additionally, in each group, subjects with ODP were divided into two age subgroups around the median age. A non-contact ultrasonic method was used to measure corneal indentation pulse (CIP) synchronically with the acquisition of electrocardiography (ECG) and blood pulse signals. ODP was assessed from the acquired signals that were numerically processed in a custom written program. Results ODP incidence was about 78%, 66%, 66% and 84% for CG, GODA, POAG, and PACG group, respectively. With advancing age, the ODP incidence increased for all subjects (Δ = 12%), the highest being for the PACG and POAG groups (Δ = 30%). GODA group did not show an age-related increase in the incidence of ODP. Conclusions The ocular dicrotism, measured with non-contact ultrasonic method, was found to be a common phenomenon in elderly subjects. The increased ODP incidence in PACG and POAG group may correspond to either higher stiffness of glaucoma eyes, biochemical abnormalities in eye tissues, changes in ocular hemodynamics, may reflect the effect of medications or be a combination of all those factors. The results of GODA group suggest different mechanisms governing their ocular pulse that makes them less susceptible to generating ODP and having decreased predisposition to glaucoma. PMID:25032962

  15. UV-induced retinal proteome changes in the rat model of age-related macular degeneration.

    PubMed

    Kraljević Pavelić, Sandra; Klobučar, Marko; Sedić, Mirela; Micek, Vedran; Gehrig, Peter; Grossman, Jonas; Pavelić, Krešimir; Vojniković, Božidar

    2015-09-01

    Age-related macular degeneration (AMD) is characterized by irreversible damage of photoreceptors in the central posterior part of the retina, called the macula and is the most common cause of vision loss in those aged over 50. A growing body of evidence shows that cumulative long-term exposure to UV radiation may be harmful to the retina and possibly leads to AMD irrespective of age. In spite of many research efforts, cellular and molecular mechanisms leading to UV-induced retinal damage and possibly retinal diseases such as AMD are not completely understood. In the present study we explored damage mechanisms accounting for UV-induced retinal phototoxicity in the rats exposed to UVA and UVB irradiation using a proteomics approach. Our study showed that UV irradiation induces profound changes in the retinal proteomes of the rats associated with the disruption of energy homeostasis, oxidative stress, DNA damage response and structural and functional impairments of the interphotoreceptor matrix components and their cell surface receptors such as galectins. Two small leucine-rich proteoglycans, biglycan and lumican, were identified as phototoxicity biomarkers associated with UV-induced disruption of interphotoreceptor matrix (IPM). In addition, UVB induced activation of Src kinase, which could account for cytoskeletal rearrangements in the retina was observed at the proteomics level. Pharmacological intervention either to target Src kinase with the aim of preventing cytoskeletal rearrangements in the retinal pigment epithelium (RPE) and neuronal retina or to help rebuild damaged IPM may provide fresh avenues of treatment for patients suffering from AMD. PMID:26071645

  16. Age-related changes of neuro-endocrine-immune interactions in healthy humans.

    PubMed

    Mazzoccoli, G; Correra, M; Bianco, G; De Cata, A; Balzanelli, M; Giuliani, A; Tarquini, R

    1997-01-01

    Numerous interactions exist among the nervous, endocrine and immune systems, mediated by neurotransmitters, hormones and cytokines. The function of these systems shows patterns of circadian rhythmicity and a number of age-related changes in the 24-hour hormonal and nonhormonal rhythms have been found in older human beings. The aim of this study was to evaluate the presence of altered integration among the nervous, endocrine and immune systems in older adults. Cortisol, melatonin, thyrotropin-releasing hormone (TRH), thyroid-stimulatinghormone (TSH), free thyroxine (FT4), growth hormone (GH), insulin-like growth factor I (IGF-I) and interleukin 2 (IL-2) serum levels were measured and lymphocyte subpopulation analyses were performed on blood samples collected every four hours for 24 hours from seven healthy young subjects aged 36-58 years (mean age +/- s.e. 45.28 +/- 3.31) and from seven healthy old subjects aged 65-78 years (mean age +/- s.e. 68.57 +/- 1.91). There was a statistically significant difference between the groups in the observed values of CD20 (total B cells, higher in the young subjects, t = 2.48, P = 0.028) and CD25 (activated T cells with expression of the alpha chain of IL-2 receptor, higher in elderly subjects, t = -2.23, P = 0.045); DR+ T cells were also higher in elderly subjects, T=34.0, P=0.01). There was no statistically significant difference in the observed values of CD2(total T lymphocytes), CD4 (helper/inducer T cells), CD8 (suppressor/cytotoxic T cells), CD4/CD8 ratio, CD16 (natural killer cells), HLA-DR (B cells and activated T cells), TcR delta 1 (epitope of the constant domain of delta chain of T-cell receptor 1), cortisol, melatonin, TRH, TSH, FT4" GH, IGF-I, IL-2. In the group of younger subjects a clear circadian rhythm was validated for the time-qualified changes of all the factors studied, with the exception of CD16, FT4 and IL-2. In the group of elderly subjects a clear circadian rhythm was validated for the nyctohemeral changes

  17. Age-related changes in production and below-ground carbon allocation in Pinus contorta forests

    SciTech Connect

    Smith, F.W.; Resh, S.C.

    1999-08-01

    A decline in wood production and above-ground net primary production (ANPP) following an early maximum is a widely observed feature of forest development. Why should relatively young, seemingly vigorous even-aged forests undergo this decrease in production? The authors measured above-ground net primary production and below-ground carbon allocation in an age sequence of lodgepole pine forest in south-central Wyoming spanning 260 yr of forest development. ANPP and total root carbon allocation (TRCA) are examined to determine if there is an increase in TRCA of sufficient magnitude to offset the observed decrease in ANPP in developing lodgepole forests. Also, they examined changes in canopy structure, leaf area efficiency (E), and above-ground carbon allocation patterns to determine their potential role in the age-related decrease in ANPP. ANPP declined by 50% between peak production of 192 gC m{sup {minus}2}yr{sup {minus}1} at age 30 to 92 gC m{sup {minus}2}yr{sup {minus}1} at age 260, largely as a decrease in stem wood production. TRCA was similar for forests from 30 to 100 yr old, but was significantly less in 260-yr-old forest at 391 gC m{sup {minus}2}yr{sup {minus}1} than in younger lodgepole forests at 516 gC m{sup {minus}2}yr{sup {minus}1}. Declining ANPP was not due to an increase in carbon allocation to below-ground production. Net primary production (NPP), the total of above-ground and below-ground NPP, declined by 36% from 450 gC m{sup {minus}2}yr{sup {minus}1} at age 30 to 288 gC m{sup {minus}2}yr{sup {minus}1} at age 260. This progressive decline in NPP was associated with changes in stand structure that occur during stand development, including decreased leaf area, shifting carbon allocation, and decline in leaf area efficiency. The results suggest that a combination of several factors, acting in concert, produce the observed decline in ANPP associated with the development of even-ages lodgepole pine forests.

  18. Age-related effects on spatial memory across viewpoint changes relative to different reference frames.

    PubMed

    Montefinese, Maria; Sulpizio, Valentina; Galati, Gaspare; Committeri, Giorgia

    2015-07-01

    Remembering object positions across different views is a fundamental competence for acting and moving appropriately in a large-scale space. Behavioural and neurological changes in elderly subjects suggest that the spatial representations of the environment might decline compared to young participants. However, no data are available on the use of different reference frames within topographical space in aging. Here we investigated the use of allocentric and egocentric frames in aging, by asking young and older participants to encode the location of a target in a virtual room relative either to stable features of the room (allocentric environment-based frame), or to an unstable objects set (allocentric objects-based frame), or to the viewer's viewpoint (egocentric frame). After a viewpoint change of 0° (absent), 45° (small) or 135° (large), participants judged whether the target was in the same spatial position as before relative to one of the three frames. Results revealed a different susceptibility to viewpoint changes in older than young participants. Importantly, we detected a worst performance, in terms of reaction times, for older than young participants in the allocentric frames. The deficit was more marked for the environment-based frame, for which a lower sensitivity was revealed as well as a worst performance even when no viewpoint change occurred. Our data provide new evidence of a greater vulnerability of the allocentric, in particular environment-based, spatial coding with aging, in line with the retrogenesis theory according to which cognitive changes in aging reverse the sequence of acquisition in mental development. PMID:25037856

  19. Age-related changes in optimality and motor variability: an example of multifinger redundant tasks

    PubMed Central

    Park, Jaebum; Sun, Yao; Zatsiorsky, Vladimir M.

    2011-01-01

    We used two methods, analytical inverse optimization (ANIO) and uncontrolled manifold (UCM) analysis of synergies, to explore age-related changes in finger coordination during accurate force and moment of force production tasks. The two methods address two aspects of the control of redundant systems: Finding an optimal solution (an optimal sharing pattern) and using variable solutions across trials (covarying finger forces) that are equally able to solve the task. Young and elderly subjects produced accurate combinations of total force and moment by pressing with the four fingers of the dominant hand on individual force sensors. In session-1, single trials covered a broad range of force–moment combinations. Principal component (PC) analysis showed that the first two PCs explained about 90% and 75% of finger force variance for the young and elderly groups, respectively. The magnitudes of the loading coefficients in the PCs suggested that the young subjects used mechanical advantage to produce moment while elderly subjects did not (confirmed by analysis of moments produced by individual digits). A co-contraction index was computed reflecting the magnitude of moment produced by fingers acting against the required direction of the total moment. This index was significantly higher in the young group. The ANIO approach yielded a quadratic cost function with linear terms. In the elderly group, the contribution of the forces produced by the middle and ring fingers to the cost function value was much smaller than in the young group. The angle between the plane of experimental observations and the plane of optimal solutions (D-angle), was very small (about 1.5°) in the young group and significantly larger (about 5°) in the elderly group. In session-2, four force–moment combinations were used with multiple trials at each. Covariation among finger forces (multifinger synergies) stabilizing total force, total moment, and both was seen in both groups with larger synergy

  20. Age-related changes in optimality and motor variability: an example of multifinger redundant tasks.

    PubMed

    Park, Jaebum; Sun, Yao; Zatsiorsky, Vladimir M; Latash, Mark L

    2011-07-01

    We used two methods, analytical inverse optimization (ANIO) and uncontrolled manifold (UCM) analysis of synergies, to explore age-related changes in finger coordination during accurate force and moment of force production tasks. The two methods address two aspects of the control of redundant systems: Finding an optimal solution (an optimal sharing pattern) and using variable solutions across trials (covarying finger forces) that are equally able to solve the task. Young and elderly subjects produced accurate combinations of total force and moment by pressing with the four fingers of the dominant hand on individual force sensors. In session-1, single trials covered a broad range of force-moment combinations. Principal component (PC) analysis showed that the first two PCs explained about 90% and 75% of finger force variance for the young and elderly groups, respectively. The magnitudes of the loading coefficients in the PCs suggested that the young subjects used mechanical advantage to produce moment while elderly subjects did not (confirmed by analysis of moments produced by individual digits). A co-contraction index was computed reflecting the magnitude of moment produced by fingers acting against the required direction of the total moment. This index was significantly higher in the young group. The ANIO approach yielded a quadratic cost function with linear terms. In the elderly group, the contribution of the forces produced by the middle and ring fingers to the cost function value was much smaller than in the young group. The angle between the plane of experimental observations and the plane of optimal solutions (D-angle), was very small (about 1.5°) in the young group and significantly larger (about 5°) in the elderly group. In session-2, four force-moment combinations were used with multiple trials at each. Covariation among finger forces (multifinger synergies) stabilizing total force, total moment, and both was seen in both groups with larger synergy

  1. Age-related changes in ac-impedance spectroscopy studies of normal human dentine: further investigations.

    PubMed

    Eldarrat, A H; High, A S; Kale, G M

    2010-01-01

    One of the age-related changes occurring in dentine structure is the formation of peritubular dentine on the inner walls of dentinal tubules leading to complete closure of tubules. Ac-impedance is safe, fast and non-invasive technique. In the last decade, the popularity of the technique has increased in dental research. Several investigators have used the technique to detect tooth cracks and caries. The results of in vitro studies showed that ac-impedance technique was more advanced for caries detection than visual and radiographic methods. However, other studies demonstrated that the accuracy of impedance measurements can be affected by many factors such as remineralization after tooth eruption. A study has been published on effect of age on impedance measurements by the authors for two age groups by employing ac-impedance spectroscopy. Therefore, the aim of this study was to demonstrate the importance of this technique by conducting further investigations on dentine samples of wider age groups. Dentine samples were prepared from extracted sound third molars of known patient age. The ac-impedance measurements were carried out over a wide range of frequency. After performing all electrical measurements, dentine samples were examined under SEM to correlate the electrical measurements with their structure. Impedance measurements showed that there were differences in impedance between young and old dentine. One-way ANOVA of the means of resistance and capacitance for all age groups (20, 25, 30, 40 and 50 years old dentine) revealed a significant difference (ANOVA, P < 0.0001) as a function of age. Applying Tukey's post hoc test, to the same data showed that this difference was due to the 50 years old dentine for resistance and was due to the 40 and 50 years old dentine for capacitance which were statistically different to all other groups. SEM investigation of dentine samples showed that young dentine is characterized by open dentinal tubules distributed all over the

  2. A BOLD Perspective on Age-Related Neurometabolic-Flow Coupling and Neural Efficiency Changes in Human Visual Cortex

    PubMed Central

    Hutchison, Joanna Lynn; Shokri-Kojori, Ehsan; Lu, Hanzhang; Rypma, Bart

    2013-01-01

    Age-related performance declines in visual tasks have been attributed to reductions in processing efficiency. The neural basis of these declines has been explored by comparing the blood-oxygen-level-dependent (BOLD) index of neural activity in older and younger adults during visual task performance. However, neural activity is one of many factors that change with age and lead to BOLD signal differences. We investigated the origin of age-related BOLD changes by comparing blood flow and oxygen metabolic constituents of BOLD signal. Subjects periodically viewed flickering annuli and pressed a button when detecting luminance changes in a central fixation cross. Using magnetic resonance dual-echo arterial spin labeling and CO2 ingestion, we observed age-equivalent (i.e., similar in older and younger groups) fractional cerebral blood flow (ΔCBF) in the presence of age-related increases in fractional cerebral metabolic rate of oxygen (ΔCMRO2). Reductions in ΔCBF responsiveness to increased ΔCMRO2 in elderly led to paradoxical age-related BOLD decreases. Age-related ΔCBF/ΔCMRO2 ratio decreases were associated with reaction times, suggesting that age-related slowing resulted from less efficient neural activity. We hypothesized that reduced vascular responsiveness to neural metabolic demand would lead to a reduction in ΔCBF/ΔCMRO2. A simulation of BOLD relative to ΔCMRO2 for lower and higher neurometabolic-flow coupling ratios (approximating those for old and young, respectively) indicated less BOLD signal change in old than young in relatively lower CMRO2 ranges, as well as greater BOLD signal change in young compared to old in relatively higher CMRO2 ranges. These results suggest that age-comparative studies relying on BOLD signal might be misinterpreted, as age-related BOLD changes do not merely reflect neural activity changes. Age-related declines in neurometabolic-flow coupling might lead to neural efficiency reductions that can adversely affect visual task

  3. Influence of regular exercise on age-related changes in arterial elasticity: mechanistic insights from wall compositions in rat aorta.

    PubMed

    Nosaka, Toshiya; Tanaka, Hirofumi; Watanabe, Izumi; Sato, Masaaki; Matsuda, Mitsuo

    2003-04-01

    Arterial stiffness increases with age in healthy sedentary adults. We previously reported that the age-related increases in arterial stiffness are absent or attenuated in regularly exercising adults. However, the mechanism underlying this training effect is unknown. One possibility is that regular exercise minimizes age-related changes in the arterial wall composition of elastin and collagen. To gain insight into this issue, we studied four groups of rats (N = 23): young (42-46 wks) and old (80-84 wks), sedentary and exercise-trained. The exercise group swam 1 hr.d-1, 6 d.wk-1 for 17-21 weeks. There was no significant difference in the incremental elastic modulus between young sedentary and exercise-trained rats. The elastic moduli of the old exercise-trained rats were 31% lower than in the old sedentary controls. As such, the magnitude of age-related increase in the elastic modulus was smaller in the exercise-trained (110%) vs. the sedentary group (151%) (p < 0.05). In both activity groups, elastin content was lower and collagen content was higher in old vs. young rats (p < 0.05). However, there were no significant differences between the two activity groups. These results are not consistent with the hypothesis that regular physical exercise minimizes age-related compositional changes in the arterial wall and attenuates the age-related increase in arterial stiffness.

  4. Hope for the best, prepare for the worst? Future self-views and preparation for age-related changes.

    PubMed

    Kornadt, Anna E; Voss, Peggy; Rothermund, Klaus

    2015-12-01

    Extending research on the impact of views on aging and developmental regulation across the life span, we tested the hypothesis that more positive views of oneself as an older person predict more preparation for age-related changes. Drawing on recent evidence regarding the domain specificity of aging-related developmental processes, we assumed this relationship to be moderated by the relevance of preparation in different life domains for different age groups. We investigated these research questions in a longitudinal study that assessed future self-views and preparation for different life domains in a sample covering a large part of the adult life span. Findings supported our hypotheses: More positive/negative personal views of one's own aging at T1 predicted subsequent increases/decreases in preparation, with influences being strongest for those domains in which relevant age-related changes are expected to occur for the respective age groups. Our study provides additional evidence for the idea that views on aging shape development, identifying age-related provision making as an important mediating process. Furthermore, our findings highlight the added value of a domain-specific approach that takes the differential relevance of life domains and age-related developmental tasks into account.

  5. Age-related structural changes in upper extremity muscle tissue in a non-human primate model

    PubMed Central

    Santago, Anthony C.; Plate, Johannes F.; Shively, Carol A.; Register, Thomas C.; Smith, Thomas L.; Saul, Katherine R.

    2015-01-01

    Background Longitudinal studies of upper extremity aging in humans include logistical concerns that animal models can overcome. The vervet is a promising species with which to study aging related processes. However, age-related changes in upper extremity muscle structure have not been quantified in this species. This study measured age-related changes to muscle structure, examined relationships between muscle structure and measures of physical performance, and evaluated the presence of rotator cuff tears. Methods Muscle structure: volume, optimal fiber length, physiological cross-sectional area (PCSA), of 10 upper extremity muscles was quantified from the right upper limb of 5 middle aged and 6 older adult female vervets. Results Total measured PCSA was smaller (p=0.001) in the older adult vervets than the middle aged vervets. Muscle volume reduction predominate the age-related reductions in PCSA. Total measured PCSA was not correlated to any measures of physical performance. No rotator cuff tears were observed. Supraspinatus volume was relatively larger and deltoid volume relatively smaller in the vervet compared to a human. Conclusion The vervet is an appropriate translational model for age-related upper extremity muscle volume loss. Functional measures were not correlated to PCSA, suggesting the vervets may have enough strength for normal function despite loss of muscle tissue. Reduced relative demand on the supraspinatus may be responsible for the lack of naturally occurring rotator cuff tears. PMID:25963066

  6. Hope for the best, prepare for the worst? Future self-views and preparation for age-related changes.

    PubMed

    Kornadt, Anna E; Voss, Peggy; Rothermund, Klaus

    2015-12-01

    Extending research on the impact of views on aging and developmental regulation across the life span, we tested the hypothesis that more positive views of oneself as an older person predict more preparation for age-related changes. Drawing on recent evidence regarding the domain specificity of aging-related developmental processes, we assumed this relationship to be moderated by the relevance of preparation in different life domains for different age groups. We investigated these research questions in a longitudinal study that assessed future self-views and preparation for different life domains in a sample covering a large part of the adult life span. Findings supported our hypotheses: More positive/negative personal views of one's own aging at T1 predicted subsequent increases/decreases in preparation, with influences being strongest for those domains in which relevant age-related changes are expected to occur for the respective age groups. Our study provides additional evidence for the idea that views on aging shape development, identifying age-related provision making as an important mediating process. Furthermore, our findings highlight the added value of a domain-specific approach that takes the differential relevance of life domains and age-related developmental tasks into account. PMID:26302028

  7. Age-related changes in human posture control: Sensory organization tests

    NASA Technical Reports Server (NTRS)

    Peterka, R. J.; Black, F. O.

    1989-01-01

    Postural control was measured in 214 human subjects ranging in age from 7 to 81 years. Sensory organization tests measured the magnitude of anterior-posterior body sway during six 21 s trials in which visual and somatosensory orientation cues were altered (by rotating the visual surround and support surface in proportion to the subject's sway) or vision eliminated (eyes closed) in various combinations. No age-related increase in postural sway was found for subjects standing on a fixed support surface with eyes open or closed. However, age-related increases in sway were found for conditions involving altered visual or somatosensory cues. Subjects older than about 55 years showed the largest sway increases. Subjects younger than about 15 years were also sensitive to alteration of sensory cues. On average, the older subjects were more affected by altered visual cues whereas younger subjects had more difficulty with altered somatosensory cues.

  8. Brain site-specific proteome changes in aging-related dementia

    PubMed Central

    Manavalan, Arulmani; Mishra, Manisha; Feng, Lin; Sze, Siu Kwan; Akatsu, Hiroyasu; Heese, Klaus

    2013-01-01

    This study is aimed at gaining insights into the brain site-specific proteomic senescence signature while comparing physiologically aged brains with aging-related dementia brains (for example, Alzheimer's disease (AD)). Our study of proteomic differences within the hippocampus (Hp), parietal cortex (pCx) and cerebellum (Cb) could provide conceptual insights into the molecular mechanisms involved in aging-related neurodegeneration. Using an isobaric tag for relative and absolute quantitation (iTRAQ)-based two-dimensional liquid chromatography coupled with tandem mass spectrometry (2D-LC-MS/MS) brain site-specific proteomic strategy, we identified 950 proteins in the Hp, pCx and Cb of AD brains. Of these proteins, 31 were significantly altered. Most of the differentially regulated proteins are involved in molecular transport, nervous system development, synaptic plasticity and apoptosis. Particularly, proteins such as Gelsolin (GSN), Tenascin-R (TNR) and AHNAK could potentially act as novel biomarkers of aging-related neurodegeneration. Importantly, our Ingenuity Pathway Analysis (IPA)-based network analysis further revealed ubiquitin C (UBC) as a pivotal protein to interact with diverse AD-associated pathophysiological molecular factors and suggests the reduced ubiquitin proteasome degradation system (UPS) as one of the causative factors of AD. PMID:24008896

  9. Differential age-related changes in mitochondrial DNA repair activities in mouse brain regions

    PubMed Central

    Gredilla, Ricardo; Garm, Christian; Holm, Rikke; Bohr, Vilhelm A.; Stevnsner, Tinna

    2008-01-01

    Aging in the brain is characterized by increased susceptibility to neuronal loss and functional decline, and mitochondrial DNA (mtDNA) mutations are thought to play an important role in these processes. Due to the proximity of mtDNA to the main sites of mitochondrial free radical generation, oxidative stress is a major source of DNA mutations in mitochondria. The base excision repair (BER) pathway removes oxidative lesions from mtDNA, thereby constituting an important mechanism to avoid accumulation of mtDNA mutations. The complexity of the brain implies that exposure and defence against oxidative stress varies among brain regions and hence some regions may be particularly prone to accumulation of mtDNA damages. In the current study we investigated the efficiency of the BER pathway throughout the murine lifespan in mitochondria from cortex and hippocampus, regions that are central in mammalian cognition, and which are severely affected during aging and in neurodegenerative diseases. A regional specific regulation of mitochondrial DNA repair activities was observed with aging. In cortical mitochondria, DNA glycosylase activities peaked at middle-age followed by a significant drop at old age. However, only minor changes were observed in hippocampal mitochondria during the whole lifespan of the animals. Furthermore, DNA glycosylase activities were lower in hippocampal than in cortical mitochondria. Mitochondrial AP endonuclease activity increased in old animals in both brain regions. Our data suggest an important regional specific regulation of mitochondrial BER during aging. PMID:18701195

  10. Age-related changes in working memory during sentence comprehension: an fMRI study.

    PubMed

    Grossman, Murray; Cooke, Ayanna; DeVita, Chris; Alsop, David; Detre, John; Chen, Willis; Gee, James

    2002-02-01

    Sentence comprehension declines with age, but the neural basis for this change is unclear. We monitored regional brain activity in 13 younger subjects and 11 healthy seniors matched for sentence comprehension accuracy while they answered a simple probe about written sentences. The sentences varied in their grammatical features (subject-relative vs object-relative subordinate clause) and their verbal working memory (WM) demands (short vs long antecedent noun-gap linkage). We found that young and senior subjects both recruit a core written sentence processing network, including left posterolateral temporal and bilateral occipital cortex for all sentences, and ventral portions of left inferior frontal cortex for object-relative sentences with a long noun-gap linkage. Differences in activation patterns for seniors compared to younger subjects were due largely to changes in brain regions associated with a verbal WM network. While seniors had less left parietal recruitment than younger subjects, left premotor cortex, and dorsal portions of left inferior frontal cortex showed greater activation in seniors compared to younger subjects. Younger subjects recruited right posterolateral temporal cortex for sentences with a long noun-gap linkage. Seniors additionally recruited right parietal cortex for this sentence-specific form of WM. Our findings are consistent with the hypothesis that the neural basis for sentence comprehension includes dissociable but interactive large-scale neural networks supporting core written sentence processes and related cognitive resources involved in WM. Seniors with good comprehension appear to up-regulate portions of the neural substrate for WM during sentence processing to achieve comprehension accuracy that equals young subjects.

  11. Normal age-related brain morphometric changes: nonuniformity across cortical thickness, surface area and gray matter volume?

    PubMed

    Lemaitre, Herve; Goldman, Aaron L; Sambataro, Fabio; Verchinski, Beth A; Meyer-Lindenberg, Andreas; Weinberger, Daniel R; Mattay, Venkata S

    2012-03-01

    Normal aging is accompanied by global as well as regional structural changes. While these age-related changes in gray matter volume have been extensively studied, less has been done using newer morphological indexes, such as cortical thickness and surface area. To this end, we analyzed structural images of 216 healthy volunteers, ranging from 18 to 87 years of age, using a surface-based automated parcellation approach. Linear regressions of age revealed a concomitant global age-related reduction in cortical thickness, surface area and volume. Cortical thickness and volume collectively confirmed the vulnerability of the prefrontal cortex, whereas in other cortical regions, such as in the parietal cortex, thickness was the only measure sensitive to the pronounced age-related atrophy. No cortical regions showed more surface area reduction than the global average. The distinction between these morphological measures may provide valuable information to dissect age-related structural changes of the brain, with each of these indexes probably reflecting specific histological changes occurring during aging. PMID:20739099

  12. Age-Related Changes in Segmental Body Composition by Ethnicity and History of Weight Change across the Adult Lifespan

    PubMed Central

    Tian, Simiao; Morio, Béatrice; Denis, Jean-Baptiste; Mioche, Laurence

    2016-01-01

    This study assessed age-related changes in body composition (specifically in trunk fat and appendicular lean masses), with consideration of body mass index (BMI) at age 20 years (BMI reference age, “BMIref”), ethnicity and lifetime weight change history. A cross-sectional dual-energy X-ray absorptiometry-based dataset was extracted from the U.S. National Health and Nutrition Examination Survey (NHANES) 1999–2004. Only European-American and African-American subjects were used (2705 men, 2527 women). For each gender and ethnicity, 6 analytic cases were considered, based on three BMIref categories (normal, overweight and obese, being 22, 27 and 30 kg/m2, respectively) and two weight contexts (stable weight or weight gain across the lifespan). A nonparametric model was developed to investigate age-related changes in body composition. Then, parametric modelling was developed for assessing BMIref- and ethnicity-specific effects during aging. In the stable weight, both genders’ and ethnicities’ trunk fat (TF) increased gradually; body fat (BF) remained stable until 40 years and increased thereafter; trunk lean (TL) remained stable, but appendicular lean (APL) and body lean (BL) declined from 20 years. In the weight gain context, TF and BF increased at a constant rate, while APL, TL and BL increased until 40–50 years, and then declined slightly. Compared with European-American subjects of both genders, African-American subjects had lower TF and BF masses. Ethnic differences in body composition were quantified and found to remain constant across the lifespan. PMID:27529269

  13. Age-Related Changes in Segmental Body Composition by Ethnicity and History of Weight Change across the Adult Lifespan.

    PubMed

    Tian, Simiao; Morio, Béatrice; Denis, Jean-Baptiste; Mioche, Laurence

    2016-01-01

    This study assessed age-related changes in body composition (specifically in trunk fat and appendicular lean masses), with consideration of body mass index (BMI) at age 20 years (BMI reference age, "BMIref"), ethnicity and lifetime weight change history. A cross-sectional dual-energy X-ray absorptiometry-based dataset was extracted from the U.S. National Health and Nutrition Examination Survey (NHANES) 1999-2004. Only European-American and African-American subjects were used (2705 men, 2527 women). For each gender and ethnicity, 6 analytic cases were considered, based on three BMIref categories (normal, overweight and obese, being 22, 27 and 30 kg/m², respectively) and two weight contexts (stable weight or weight gain across the lifespan). A nonparametric model was developed to investigate age-related changes in body composition. Then, parametric modelling was developed for assessing BMIref- and ethnicity-specific effects during aging. In the stable weight, both genders' and ethnicities' trunk fat (TF) increased gradually; body fat (BF) remained stable until 40 years and increased thereafter; trunk lean (TL) remained stable, but appendicular lean (APL) and body lean (BL) declined from 20 years. In the weight gain context, TF and BF increased at a constant rate, while APL, TL and BL increased until 40-50 years, and then declined slightly. Compared with European-American subjects of both genders, African-American subjects had lower TF and BF masses. Ethnic differences in body composition were quantified and found to remain constant across the lifespan. PMID:27529269

  14. Age-related changes in the hippocampus (loss of synaptophysin and glial-synaptic interaction) are modified by systemic treatment with an NCAM-derived peptide, FGL.

    PubMed

    Ojo, Bunmi; Rezaie, Payam; Gabbott, Paul L; Davies, Heather; Colyer, Frances; Cowley, Thelma R; Lynch, Marina; Stewart, Michael G

    2012-07-01

    Altered synaptic morphology, progressive loss of synapses and glial (astrocyte and microglial) cell activation are considered as characteristic hallmarks of aging. Recent evidence suggests that there is a concomitant age-related decrease in expression of the presynaptic protein, synaptophysin, and the neuronal glycoprotein CD200, which, by interacting with its receptor, plays a role in maintaining microglia in a quiescent state. These age-related changes may be indicative of reduced neuroglial support of synapses. FG Loop (FGL) peptide synthesized from the second fibronectin type III module of neural cell adhesion molecule (NCAM), has previously been shown to attenuate age-related glial cell activation, and to 'restore' cognitive function in aged rats. The mechanisms by which FGL exerts these neuroprotective effects remain unclear, but could involve regulation of CD200, modifying glial-synaptic interactions (affecting neuroglial 'support' at synapses), or impacting directly on synaptic function. Light and electron microscopic (EM) analyses were undertaken to investigate whether systemic treatment with FGL (i) alters CD200, synaptophysin (presynaptic) and PSD-95 (postsynaptic) immunohistochemical expression levels, (ii) affects synaptic number, or (iii) exerts any effects on glial-synaptic interactions within young (4 month-old) and aged (22 month-old) rat hippocampus. Treatment with FGL attenuated the age-related loss of synaptophysin immunoreactivity (-ir) within CA3 and hilus (with no major effect on PSD-95-ir), and of CD200-ir specifically in the CA3 region. Ultrastructural morphometric analyses showed that FGL treatment (i) prevented age-related loss in astrocyte-synaptic contacts, (ii) reduced microglia-synaptic contacts in the CA3 stratum radiatum, but (iii) had no effect on the mean number of synapses in this region. These data suggest that FGL mediates its neuroprotective effects by regulating glial-synaptic interaction.

  15. Age-related changes in hypertensive brain damage in the hippocampi of spontaneously hypertensive rats

    PubMed Central

    LI, YALI; LIU, JIAN; GAO, DENGFENG; WEI, JIN; YUAN, HAIFENG; NIU, XIAOLIN; ZHANG, QIAOJUN

    2016-01-01

    The aim of the present study was to investigate the age-related alterations in hypertensive brain damage in the hippocampi of spontaneously hypertensive rats (SHR) and the underlying mechanisms. Aging resulted in a significant increase in the number of activated astrocytes and apoptotic cells in the SHR group, which was accompanied by increased expression of oxidative stress markers (iNOS and gp47phox) and apoptotic regulatory proteins (Bax and caspase-3). In addition, the expression of PPAR-γ and Bcl-2 were progressively reduced with increasing age in the SHR group. The 32 and 64-week-old SHRs exhibited significantly increased numbers of apoptotic cells, oxidative stress markers and pro-apoptotic proteins compared with age-matched WKY rats, which was accompanied by reduced expression of PPAR-γ. Compared with the 16 and 32-week-old WKY group, the 64-week-old WKY rats exhibited increased oxidative stress and pro-apoptotic markers, and increased levels apoptotic cells. In conclusion, the present study indicated that both aging and hypertension enhanced brain damage and oxidative stress injury in the hippocampi of SHRs, indicated by an increased presence of apoptotic cells and astrocytes. In addition, reduced expression of PPAR-γ may contribute to the age-related brain damage in SHRs. PMID:26846626

  16. Future time perspective and awareness of age-related change: Examining their role in predicting psychological well-being.

    PubMed

    Brothers, Allyson; Gabrian, Martina; Wahl, Hans-Werner; Diehl, Manfred

    2016-09-01

    This study examined how 2 distinct facets of perceived personal lifetime-future time perspective (FTP) and awareness of age-related change (AARC)-are associated with another, and how they may interact to predict psychological well-being. To better understand associations among subjective perceptions of lifetime, aging, and well-being, we tested a series of models to investigate questions of directionality, indirect effects, and conditional processes among FTP, AARC-Gains, AARC-Losses, and psychological well-being. In all models, we tested for differences between middle-aged and older adults, and between adults from the United States and Germany. Analyses were conducted within a structural equation modeling framework on a cross-national, 2.5-year longitudinal sample of 537 community-residing adults (age 40-98 years). Awareness of age-related losses (AARC-Losses) at Time 1 predicted FTP at Time 2, but FTP did not predict AARC-Gains or AARC-Losses. Furthermore, future time perspective mediated the association between AARC-Losses and well-being. Moderation analyses revealed a buffering effect of awareness of age-related gains (AARC-Gains) in which perceptions of more age-related gains diminished the negative effect of a limited future time perspective on well-being. Effects were robust across age groups and countries. Taken together, these findings suggest that perceived age-related loss experiences may sensitize individuals to perceive a more limited future lifetime which may then lead to lower psychological well-being. In contrast, perceived age-related gains may function as a resource to preserve psychological well-being, in particular when time is perceived as running out. (PsycINFO Database Record

  17. Age-related changes in monocytes exacerbate neointimal hyperplasia after vascular injury

    PubMed Central

    Martinez, Laisel; Gomez, Camilo; Vazquez-Padron, Roberto I.

    2015-01-01

    Neointimal hyperplasia is the leading cause of restenosis after endovascular interventions. It is characterized by the accumulation of myofibroblast-like cells and extracellular matrix in the innermost layer of the wall and is exacerbated by inflammation. Monocytes from either young or aged rats were applied perivascularly to injured vascular walls of young recipient animals. Monocytes from aged rats, but not young donors, increased neointima thickness. Accordingly, the gene expression profiles of CD11b+ monocytes from aged rats showed significant up-regulation of genes involved in cellular adhesion, lipid degradation, cytotoxicity, differentiation, and inflammation. These included cadherin 13 (Cdh13), colony stimulating factor 1 (Csf1), chemokine C-X-C motif ligand 1 (Cxcl1), endothelial cell-selective adhesion molecule (Esam), and interferon gamma (Ifng). In conclusion, our results suggest that the increased inflammatory and adhesive profile of monocytes contributes to pathological wall remodeling in aged-related vascular diseases. PMID:25965835

  18. Age-Related Physical Changes Interfere With Judgments of Male Sexual Orientation From Faces.

    PubMed

    Tskhay, Konstantin O; Krendl, Anne C; Rule, Nicholas O

    2016-09-01

    Although studies have shown that sexual orientation can be judged from faces, this research has not considered how age-related differences in perceivers or targets affect such judgments. In the current work, we evaluated whether accuracy differed among young adults (YA) and older adults (OA) for young and old men's faces by recruiting a sample of YA and OA in the lab, a community sample of sexual minority men, and a sample of online participants. We found that OA and YA judged sexual orientation with similar accuracy. Perceptions of gender atypicality mediated the difference in judging older and younger targets' sexual orientation. Although participants used positive affect to correctly discern sexual orientation regardless of target age, perceptions of masculinity were valid only for judgments of YA.

  19. Age-related changes in the biomechanics of healing patellar tendon.

    PubMed

    Dressler, M R; Butler, D L; Boivin, G P

    2006-01-01

    By 2030, there will be 70 million people in the United States over the age of 65, and by 2050, 22% of the US population will be considered elderly. It is generally believed that injuries in the elderly heal slower and less completely than in adolescents or young adults. To evaluate aging effects on tissue repair a surgical injury was created in the middle third of one patellar tendon in 1- and 4-5-year-old New Zealand White rabbits. The biomechanical properties of the isolated repair tissues and contralateral normal tendon tissues were compared at 6, 12 and 26 weeks post-injury. We hypothesized that repair tissues would exhibit age-related reductions in biomechanical properties at all time intervals of healing, both based on raw data and when normalized to values from contralateral tendons. Repairs from both age groups were similar, with no significant increase in maximum stress, strain at maximum stress, or modulus between 6 and 12 weeks. At 26 weeks, the repairs in the 4-year-old rabbits had higher maximum stress values than repairs in the 1-year-old rabbits (p=0.03). There were no significant differences in the strain at maximum stress or modulus. When repair tissue properties were normalized to values in the contralateral normal tendon, the maximum stress of the patellar tendon repair tissue from the 4 year old was significantly greater than the corresponding value from the 1 year old at the 26 week time point (p=0.04). In conclusion, these findings do not support the presence of age-related declines in the biomechanics of healing tendon.

  20. Understanding age-related reductions in visual working memory capacity: Examining the stages of change detection

    PubMed Central

    Duda, Bryant; Hussey, Erin; Mason, Emily; Molitor, Robert J.; Woodman, Geoffrey F.; Ally, Brandon A.

    2014-01-01

    Visual working memory (VWM) capacity is reduced in older adults. Research has shown age-related impairments to VWM encoding, but aging is likely to affect multiple stages of VWM. In the present study, we recorded the event-related potentials (ERPs) of younger and older adults during VWM maintenance and retrieval. We measured encoding-stage processing with the P1 component, maintenance-stage processing with the contralateral delay activity (CDA), and retrieval-stage processing by comparing the activity for old and new items (old–new effect). Older adults showed lower behavioral capacity estimates (K) than did younger adults, but surprisingly, their P1 components and CDAs were comparable to those of younger adults. This remarkable dissociation between neural activity and behavior in the older adults indicated that the P1 and CDA did not accurately assess their VWM capacity. However, the neural activity evoked during VWM retrieval yielded results that helped clarify the age-related differences. During retrieval, younger adults showed early old–new effects in frontal and occipital areas and a late central–parietal old–new effect, whereas older adults showed a late right-lateralized parietal old–new effect. The younger adults’ early old–new effects strongly resembled an index of perceptual fluency, suggesting that perceptual implicit memory was activated. The activation of implicit memory could have facilitated the younger adults’ behavior, and the lack of these early effects in older adults may suggest that they have much lower-resolution memory than do younger adults. From these data, we speculated that younger and older adults store the same number of items in VWM, but that younger adults store a higher-resolution representation than do older adults. PMID:24420648

  1. Hematology and blood chemistry reference values and age-related changes in wild Bearded Vultures (Gypaetus barbatus).

    PubMed

    Hernández, M; Margalida, A

    2010-04-01

    Normal hematologic and blood chemistry values for clinical use and age-related changes are reported as reference values for the endangered Bearded Vulture (Gypaetus barbatus). Blood samples were obtained from 21 nestlings and 26 free-living subadults and adults. No significant differences were found between subadults and adults or between sexes for any of the studied parameters. Reference ranges have been established for Bearded Vulture nestlings (less than 3 mo of age) and for free-living Bearded Vultures, with subadult and adult data combined without affecting clinical interpretation. Some reference values for the parameters reported in this study are similar to those previously described for vultures and other raptor species, although creatine phosphokinase and lactate dehydrogenase activities were higher than those reported for birds of prey. Significant age-related differences were identified in urea, uric acid, triglycerides, total serum protein, inorganic phosphorus, and magnesium concentrations, as well as aspartate aminotransferase, creatine phosphokinase, lactate dehydrogenase, alkaline phosphatase, amylase, and lipase activities (P<0.05). Additionally, significant age-related differences were noted in red and white blood cell counts, packed cell volume, hemoglobin concentration, mean corpuscular volume, mean corpuscular hemoglobin concentration, fibrinogen level, and heterophils, lymphocytes, and eosinophils (P<0.005). The results obtained from this study provide reference ranges that will be useful for evaluating the pathologic conditions and general health of Bearded Vulture populations and reveal the existence of important age-related differences in the species.

  2. Age-related changes in amygdala-frontal connectivity during emotional face processing from childhood into young adulthood.

    PubMed

    Wu, Minjie; Kujawa, Autumn; Lu, Lisa H; Fitzgerald, Daniel A; Klumpp, Heide; Fitzgerald, Kate D; Monk, Christopher S; Phan, K Luan

    2016-05-01

    The ability to process and respond to emotional facial expressions is a critical skill for healthy social and emotional development. There has been growing interest in understanding the neural circuitry underlying development of emotional processing, with previous research implicating functional connectivity between amygdala and frontal regions. However, existing work has focused on threatening emotional faces, raising questions regarding the extent to which these developmental patterns are specific to threat or to emotional face processing more broadly. In the current study, we examined age-related changes in brain activity and amygdala functional connectivity during an fMRI emotional face matching task (including angry, fearful, and happy faces) in 61 healthy subjects aged 7-25 years. We found age-related decreases in ventral medial prefrontal cortex activity in response to happy faces but not to angry or fearful faces, and an age-related change (shifting from positive to negative correlation) in amygdala-anterior cingulate cortex/medial prefrontal cortex (ACC/mPFC) functional connectivity to all emotional faces. Specifically, positive correlations between amygdala and ACC/mPFC in children changed to negative correlations in adults, which may suggest early emergence of bottom-up amygdala excitatory signaling to ACC/mPFC in children and later development of top-down inhibitory control of ACC/mPFC over amygdala in adults. Age-related changes in amygdala-ACC/mPFC connectivity did not vary for processing of different facial emotions, suggesting changes in amygdala-ACC/mPFC connectivity may underlie development of broad emotional processing, rather than threat-specific processing. Hum Brain Mapp 37:1684-1695, 2016. © 2016 Wiley Periodicals, Inc.

  3. Autophagy involving age-related cognitive behavior and hippocampus injury is modulated by different caloric intake in mice

    PubMed Central

    Dong, Wen; Wang, Rong; Ma, Li-Na; Xu, Bao-Lei; Zhang, Jing-Shuang; Zhao, Zhi-Wei; Wang, Yu-Lan; Zhang, Xu

    2015-01-01

    Recent studies indicated that different caloric intake may influence neuronal function. Excessive caloric intake associated with accelerated aging of the brain and increased the risk of neurodegenerative disorders. And low caloric intake (caloric restriction, CR) could delay aging, and protect the central nervous system from neurodegenerative disorders. The underlying mechanisms remain poorly understood. In this study, thirty six-week-old male C57/BL male mice were randomly divided into three different dietary groups: normal control (NC) group (fed standard diet), CR group (fed low-caloric diet) and high-calorie (HC) group (fed high-caloric diet). After 10 months, spatial memory ability was determined by Morris water maze. Pathological changes of the hippocampus cells were detected with HE and Nissl staining. The expression of proteins involved in autophagy in the hippocampus was determined by immunofluorescence and Western blot. The result of Morris water maze showed that the learning and memory capacity significantly increased in the CR group, and significantly decreased in the HC group. HE and Nissl staining showed cells damaged obviously in the HC group. The expression of mTOR and p62 was increased in the HC group, and decreased in the CR group. The expression of Beclin1, LC3 and cathepsin B was decreased in the HC group, and increased in the CR group. Our findings demonstrate that long-term high caloric intake is a risk factor that can significantly contribute to the development of neurological disease via suppressing autophagy, and CR may prevent age-related learning ability impairment via activating autophagy in mice. PMID:26380026

  4. Aging Related Changes of Retina and Optic Nerve of Uromastyx aegyptia and Falco tinnunculus

    PubMed Central

    2013-01-01

    Aging is a biological phenomenon that involves gradual degradation of the structure and function of the retina and optic nerve. To our knowledge, little is known about the aging-related ocular cell loss in avian (Falco tinnunculus) and reptilian species (Uromastyx aegyptia). A selected 90 animals of pup, middle, and old age U. aegyptia (reptilian) and F. tinnunculus (avian) were used. The retinae and optic nerves were investigated by light and transmission electron microscopy (TEM) and assessments of neurotransmitters, antioxidant enzymes (catalase, superoxide dismustase and glutathione s transferase), caspase-3 and -7, malonadialdhyde, and DNA fragmentation. Light and TEM observations of the senile specimens revealed apparent deterioration of retinal cell layers, especially the pigmented epithelium and photoreceptor outer segments. Their inclusions of melanin were replaced by lipofuscins. Also, vacuolar degeneration and demyelination of the optic nerve axons were detected. Concomitantly, there was a marked increase of oxidative stress involved reduction of neurotransmitters and antioxidant enzymes and an increase of lipid peroxidation, caspase-3 and -7, subG0/G1 apoptosis, and P53. We conclude that aging showed an inverse relationship with the neurotransmitters and antioxidant enzymes and a linear relationship of caspases, malondialdhyde, DNA apoptosis, and P53 markers of cell death. These markers reflected the retinal cytological alterations and lipofuscin accumulation within inner segments. PMID:24215233

  5. Age-related changes in auditory and visual interactions in temporal rate perception

    PubMed Central

    Brooks, Cassandra J.; Anderson, Andrew J.; Roach, Neil W.; McGraw, Paul V.; McKendrick, Allison M.

    2015-01-01

    We investigated how aging affects the integration of temporal rate for auditory flutter (amplitude modulation) presented with visual flicker. Since older adults were poorer at detecting auditory amplitude modulation, modulation depth was individually adjusted so that temporal rate was equally discriminable for 10 Hz flutter and flicker, thereby balancing the reliability of rate information available to each sensory modality. With age-related sensory differences normalized in this way, rate asynchrony skewed both auditory and visual rate judgments to the same extent in younger and older adults. Therefore, reliability-based weighting of temporal rate is preserved in older adults. Concurrent presentation of synchronous 10 Hz flicker and flutter improved temporal rate discrimination consistent with statistically optimal integration in younger but not older adults. In a control experiment, younger adults were presented with the same physical auditory stimulus as older adults. This time, rate asynchrony skewed perceived rate with greater auditory weighting rather than balanced integration. Taken together, our results indicate that integration of discrepant auditory and visual rates is not altered due to the healthy aging process once sensory deficits are accounted for, but that aging does abolish the minor improvement in discrimination performance seen in younger observers when concordant rates are integrated. PMID:26624937

  6. Age-related changes in gait for multi-surface terrain.

    PubMed

    Marigold, Daniel S; Patla, Aftab E

    2008-05-01

    The main purpose of this study was to determine the effects of aging on the variability of gait over multi-surface terrain. An additional aim was to compare this variability to walking on solid ground. Ten young adults and 10 older adults walked along a walkway which contained a middle portion with multi-surface terrain. This multi-surface terrain consisted of solid, compliant, rocky, irregular, slippery, and uneven surfaces. We examined the effects of the multi-surface terrain and age on measures of variability including step length, step width, trunk pitch and roll, trunk centre of mass (tCOM) acceleration, and head acceleration. Step, trunk, and head variability were increased on the multi-surface terrain as compared to solid ground for both young and older adults (p<0.05). Older adults demonstrated larger medial-lateral tCOM acceleration RMS (p=0.0004) and trunk roll RMS (p=0.0001) when walking on the multi-surface terrain. In addition, older adults also walked more slowly (p=0.002) and took shorter steps (p=0.003). However, there were no age-related differences in step variability. The results suggest that multi-surface terrain poses a greater challenge to balance reflected by the increased variability, particularly in older adults.

  7. Age-related changes in osteometry, bone mineral density and osteophytosis of the lumbar vertebrae in Japanese macaques.

    PubMed

    Pomchote, Porrawee

    2015-01-01

    The age-related changes in lumbar vertebrae were studied in 77 young/full adult Japanese macaques (Macaca fuscata) (40 females, 37 males), in terms of their morphometry, density and osteophytosis, and the interrelationship between these three aspects. The most common age-related pattern of morphometric changes was an initial increase during young adulthood until reaching the peak and then a subsequent decrease with age. Most of the peaks were in the age group 15-20 and 10-15 years in females and males, respectively. In both sexes, the age-related decrease in the vertebral body depth (ventro-dorsal) was greater than in the height and width. The ventral height of the vertebral body relative to the dorsal height continuously decreased with age. The trabecular bone mineral density (BMD) continuously decreased after young adulthood. However, the magnitude of the decreased trabecular BMD with age was greater in females than in males, especially in the older age groups. Osteophytosis clearly increased with age in both sexes, but males showed an earlier appearance of osteophytes and females tended to have more severe osteophytes from 15 years old upwards. A correlation between the osteometry, density, and osteophytosis severity appeared in all vertebrae, but not all of these reached statistical significance after controlling for the influence of age. Although Japanese macaques showed the higher prevalence and rapid increase of osteophytosis, a similar age change profile was observed in the lumbar vertebrae of Japanese macaques and humans.

  8. Age-related pharmacokinetic changes of acetaminophen, antipyrine, diazepam, diphenhydramine, and ofloxacin in male cynomolgus monkeys and beagle dogs.

    PubMed

    Koyanagi, Takashi; Yamaura, Yoshiyuki; Yano, Koji; Kim, Soonih; Yamazaki, Hiroshi

    2014-10-01

    1. The pharmacokinetics of acetaminophen (marker of gastric emptying), antipyrine (marker of hepatic metabolic activity and total body water), diazepam (lipophilic and highly distributed), diphenhydramine (hepatic blood flow-limited and alpha-1 acid glycoprotein bound) and ofloxacin (renally eliminated) were evaluated in cynomolgus monkeys (3-18 years old) and beagle dogs (2-11 years old) as models in elderly persons. 2. Gastric pH fluctuated with aging in monkeys and dogs. The concentration of alpha-1 acid glycoprotein appeared to be increased by aging. There were no age-related differences in the absorption rates of the drugs under the conditions used in the study. Total body fat increased and water decreased in monkeys, but these parameters did not change in dogs. 3. Hepatic blood flow decreased in both species, but a significant decrease of hepatic clearance was only seen in monkeys. Renal clearance decreased significantly with age in monkeys and showed a tendency to decrease in dogs. 4. Age-related alterations of physiological parameters in monkeys are in agreement with clinical observations in humans, except for the lack of a change in the plasma albumin concentration. Therefore, this study suggests that monkey might be a suitable animal model for prediction of age-related changes in pharmacokinetics in humans.

  9. Age-related pharmacokinetic changes of acetaminophen, antipyrine, diazepam, diphenhydramine, and ofloxacin in male cynomolgus monkeys and beagle dogs.

    PubMed

    Koyanagi, Takashi; Yamaura, Yoshiyuki; Yano, Koji; Kim, Soonih; Yamazaki, Hiroshi

    2014-10-01

    1. The pharmacokinetics of acetaminophen (marker of gastric emptying), antipyrine (marker of hepatic metabolic activity and total body water), diazepam (lipophilic and highly distributed), diphenhydramine (hepatic blood flow-limited and alpha-1 acid glycoprotein bound) and ofloxacin (renally eliminated) were evaluated in cynomolgus monkeys (3-18 years old) and beagle dogs (2-11 years old) as models in elderly persons. 2. Gastric pH fluctuated with aging in monkeys and dogs. The concentration of alpha-1 acid glycoprotein appeared to be increased by aging. There were no age-related differences in the absorption rates of the drugs under the conditions used in the study. Total body fat increased and water decreased in monkeys, but these parameters did not change in dogs. 3. Hepatic blood flow decreased in both species, but a significant decrease of hepatic clearance was only seen in monkeys. Renal clearance decreased significantly with age in monkeys and showed a tendency to decrease in dogs. 4. Age-related alterations of physiological parameters in monkeys are in agreement with clinical observations in humans, except for the lack of a change in the plasma albumin concentration. Therefore, this study suggests that monkey might be a suitable animal model for prediction of age-related changes in pharmacokinetics in humans. PMID:24650193

  10. Slowing Down: Age-Related Neurobiological Predictors of Processing Speed

    PubMed Central

    Eckert, Mark A.

    2011-01-01

    Processing speed, or the rate at which tasks can be performed, is a robust predictor of age-related cognitive decline and an indicator of independence among older adults. This review examines evidence for neurobiological predictors of age-related changes in processing speed, which is guided in part by our source based morphometry findings that unique patterns of frontal and cerebellar gray matter predict age-related variation in processing speed. These results, together with the extant literature on morphological predictors of age-related changes in processing speed, suggest that specific neural systems undergo declines and as a result slow processing speed. Future studies of processing speed – dependent neural systems will be important for identifying the etiologies for processing speed change and the development of interventions that mitigate gradual age-related declines in cognitive functioning and enhance healthy cognitive aging. PMID:21441995

  11. Age-related changes to TNF receptors affect neuron survival in the presence of beta-amyloid

    PubMed Central

    Patel, Jigisha R.; Brewer, Gregory J.

    2007-01-01

    Inflammation including local accumulations of tumor necrosis factor alpha (TNFα) is a part of Alzheimer’s disease (AD) pathology and may exacerbate age-related neurodegeneration. Most studies on TNFα and TNF neuronal receptors are conducted using embryonic neurons. Few studies consider age-related deficits that may occur in neurons. Age-related changes in susceptibility to TNFα through TNF receptor 1 (TNFR1) and receptor 2 (TNFR2) expression could increase susceptibility to β-amyloid (1-42, Abeta42). Evidence is conflicting about which receptor mediates survival and/or apoptosis. We determined how aging affects receptor expression in cultured adult rat cortical neurons. Old neurons were more susceptible to Abeta42 toxicity than middle-age neurons and the addition of TNFα was neuroprotective in middle-age, but exacerbated the toxicity from Abeta42 in old neurons. These pathologic and protective responses in old and middle-age neurons respectively correlated with higher starting TNFR1 and TNFR2 mRNA levels in old versus middle-age neurons. Middle-age neurons treated with TNFα plus Abeta42 did not show an increase in either TNFR1 or TNFR2 mRNA but old neurons showed an upregulation in TNFR2 mRNA and not TNFR1 mRNA. Despite these mRNA changes, surface immunoreactivity of both TNFR1 and TNFR2 increased with dose of TNFα in middle-age neurons. However, middle-age neurons treated with TNFα plus Abeta42 showed an upregulation in both TNFR1 and TNFR2 surface expression, whereas old neurons failed to upregulate surface expression of either receptor. These findings support the hypothesis that age-related changes in TNFα surface receptor expression contribute to the neuronal loss associated with inflammation in AD. PMID:18418902

  12. Age-related changes in human oestrogen receptor alpha function and levels in osteoblasts.

    PubMed Central

    Ankrom, M A; Patterson, J A; d'Avis, P Y; Vetter, U K; Blackman, M R; Sponseller, P D; Tayback, M; Robey, P G; Shapiro, J R; Fedarko, N S

    1998-01-01

    Oestrogen receptors (ERs) are present in human osteoblasts and mediate anti-resorptive effects on bone. Human osteoblast-like cells derived from different aged healthy female donors not on hormone replacement therapy were utilized under well-defined conditions in vitro to investigate ER function and levels. Treatment with 0.1 nM oestradiol-17beta of cell strains derived from eight young women (less than 50 years of age) increased hydroxyproline levels significantly [an average (2.2+/-0.1 S.E.M.)-fold increase], whereas cells derived from nine older women (more than 50 years of age) were not significantly affected. Similarly, cell strains, derived from younger women, transfected with a consensus oestrogen-responsive element linked to chloramphenicol acetyltransferase exhibited a greater response to oestrogen than strains derived from older women. When basal ERalpha levels were measured by enzyme immunoassay and normalized on a per cell basis, osteoblast-like strains derived from younger women (n=24) had a mean value of 2.54+/-0.16 fmol of ERalpha per 10(6) cells. In contrast, strains derived from older women (n=20) had a mean value of 5.44+/-0.48 fmol of ERalpha per 10(6) cells. An age-related increase in ERalpha number was also observed in human skin-derived fibroblasts and directly in dermal biopsies from women not on hormone replacement therapy. The results demonstrate ligand concentration-dependent ERalpha induction and indicate a loss of receptor regulation and diminution of ligand-receptor signal transduction with increasing donor age. PMID:9677341

  13. Aging related changes in determinants of muscle force generating capacity: a comparison of muscle aging in men and male rodents.

    PubMed

    Ballak, Sam B; Degens, Hans; de Haan, Arnold; Jaspers, Richard T

    2014-03-01

    Human aging is associated with a progressive decline in skeletal muscle mass and force generating capacity, however the exact mechanisms underlying these changes are not fully understood. Rodents models have often been used to enhance our understanding of mechanisms of age-related changes in human skeletal muscle. However, to what extent age-related alterations in determinants of muscle force generating capacity observed in rodents resemble those in humans has not been considered thoroughly. This review compares the effect of aging on muscle force generating determinants (muscle mass, fiber size, fiber number, fiber type distribution and muscle specific tension), in men and male rodents at similar relative age. It appears that muscle aging in male F344*BN rat resembles that in men most; 32-35-month-old rats exhibit similar signs of muscle weakness to those of 70-80-yr-old men, and the decline in 36-38-month-old rats is similar to that in men aged over 80 yrs. For male C57BL/6 mice, age-related decline in muscle force generating capacity seems to occur only at higher relative age than in men. We conclude that the effects on determinants of muscle force differ between species as well as within species, but qualitatively show the same pattern as that observed in men.

  14. Preliminary Study on Electrophysiological Changes After Cellular Autograft in Age-Related Macular Degeneration

    PubMed Central

    Limoli, Paolo Giuseppe; Vingolo, Enzo Maria; Morales, Marco Ulisses; Nebbioso, Marcella; Limoli, Celeste

    2014-01-01

    Abstract Evolving atrophic macular degeneration represents at least 80% of all macular degenerations and is currently without a standardized care. Autologous fat transplantation efficacy was demonstrated by several studies, as these cells are able to produce growth factors. The aim of the work was to demonstrate possible therapeutic effect of the joined suprachoroidal graft of adipocytes, adipose-derived stem cells (ADSCs) in stromal vascular fractions (SVFs) of adipose tissue, and platelet-rich plasma (PRP). Twelve eyes in 12 dry age-related macular degeneration (AMD) patients, aged 71.25 (SD ± 6.8) between 62 and 80 years, were analyzed. A complete ocular evaluation was performed using best corrected visual acuity (BCVA), retinographic analysis, spectral-domain optical coherence tomography, microperimetry, computerized visual field, and standard electroretinogram (ERG). Each eye received a cell in graft between choroid and sclera of mature fat cells and ADSCs in SVF enriched with PRP by means of the variant second Limoli (Limoli retinal restoration technique [LRRT]). In order to test if the differences pre- and post-treatment were significant, the Wilcoxon signed-rank test has been performed. Adverse effects were not reported in the patients. After surgery with LRRT, the most significant increase in the ERG values was recorded by scotopic rod-ERG (answer coming from the rods), from 41.26 to 60.83 μV with an average increase of 47.44% highly significant (P < 0.05). Moderately significant was the one recorded by scotopic maximal ERG (answer coming from the rods and cones), from 112.22 to 129.68 μV with an average increase of 15.56% (P < 0.1). Cell-mediated therapy based on growth factors used appears interesting because it can improve the retinal functionality responses in the short term. The ERG could, therefore, be used to monitor the effect of cell-mediated regenerative therapies. PMID:25546695

  15. Age-Related Cognitive Impairments in Mice with a Conditional Ablation of the Neural Cell Adhesion Molecule

    ERIC Educational Resources Information Center

    Bisaz, Reto; Boadas-Vaello, Pere; Genoux, David; Sandi, Carmen

    2013-01-01

    Most of the mechanisms involved in neural plasticity support cognition, and aging has a considerable effect on some of these processes. The neural cell adhesion molecule (NCAM) of the immunoglobulin superfamily plays a pivotal role in structural and functional plasticity and is required to modulate cognitive and emotional behaviors. However,…

  16. Age-Related Visual Changes and Their Impications for the Motor Skill Performance of Older Adults.

    ERIC Educational Resources Information Center

    Haywood, Kathleen M.; Trick, Linda R.

    Physical changes in and conditions of the eye associated with the normal aging process are discussed with reference to their impact on performance in physical and recreational activities. Descriptions are given of characteristic changes in visual acuity in the areas of: (1) presbyopia (inability to clearly focus near images); (2) sensitivity to…

  17. Age-related changes in rat hippocampal theta rhythms: a difference between type 1 and type 2 theta.

    PubMed

    Abe, Y; Toyosawa, K

    1999-05-01

    The age-related changes in two types of theta rhythms recorded from the hippocampus in young (4 months-old), mature (12-13 months-old) and aged (22-25 months-old) rats were investigated. The type 1 theta rhythm was measured from hippocampal EEG recorded from walking rats and the type 2 theta was measured from the EEG induced by reticular pontin oralis nucleus (PON) stimulation in urethane anesthetized rats. The peak frequency and the peak power were detected from power spectra calculated on each theta sample by fast Fourier transformation (FFT). No age-related alteration was observed on the peak frequency of type 1 theta rhythm. However, on type 2 theta rhythm, the peak frequency was decreased in the aged rats compared with the young and the mature rats. The type 2 theta rhythm is cholinergic, and therefore this result suggests that age-related deterioration can be clearly observed in the cholinergic system including the hippocampus in rats.

  18. Early age-related changes in episodic memory retrieval as revealed by event-related potentials.

    PubMed

    Guillaume, Cécile; Clochon, Patrice; Denise, Pierre; Rauchs, Géraldine; Guillery-Girard, Bérengère; Eustache, Francis; Desgranges, Béatrice

    2009-01-28

    Familiarity is better preserved than recollection in ageing. The age at which changes first occur and the slope of the subsequent decline, however, remain unclear. In this study, we investigated changes in episodic memory, by using event-related potentials (ERPs) in young (m=24), middle-aged (m=58) and older (m=70) adults. Although behavioural performance did not change before the age of 65 years, changes in ERP correlates were already present in the middle-aged adults. The ERP correlates of recollection and monitoring processes were the first to be affected by ageing, with a linear decrease as age increased. Conversely, the ERP correlate of familiarity remained unchanged, at least up to the age of 65 years. These results suggest a differential time course for the age effects on episodic retrieval. PMID:19104457

  19. Age-related changes in the central nervous system in selected domestic mammals and primates.

    PubMed

    Firląg, Maciej; Kamaszewski, Maciej; Gaca, Katarzyna; Bałasińska, Bożena

    2013-01-01

    Aging is a process which operates at many levels of physiological, genetic and molecular organization and leads inevitably to death. Brain macroscopic changes by MRI investigation during aging were observed in humans and dogs but chimpanzees did not display significant changes. This suggestion led to the statement that brain aging is different in various species. Although human brain changes, e.g. β-amyloid storage, neurofibrillary tangle formation, lipofuscin, are relatively well known, we are still looking for a suitable animal model to study the mechanisms of aging and neurodegenerative diseases. Therefore, this paper presents a comparative analysis of the changes described in the brains of senile dog, horse and gorilla. In addition we present the latest, non-invasive methods that can be applied in the diagnosis of old age in mammals. Our considerations have shown that the best animal model for further studies and observations on aging is the dog. PMID:23619226

  20. Loss of UCHL1 promotes age-related degenerative changes in the enteric nervous system

    PubMed Central

    Coulombe, Josée; Gamage, Prasanna; Gray, Madison T.; Zhang, Mei; Tang, Matthew Y.; Woulfe, John; Saffrey, M. Jill; Gray, Douglas A.

    2014-01-01

    UCHL1 (ubiquitin carboxyterminal hydrolase 1) is a deubiquitinating enzyme that is particularly abundant in neurons. From studies of a spontaneous mutation arising in a mouse line it is clear that loss of function of UCHL1 generates profound degenerative changes in the central nervous system, and it is likely that a proteolytic deficit contributes to the pathology. Here these effects were found to be recapitulated in mice in which the Uchl1 gene had been inactivated by homologous recombination. In addition to the previously documented neuropathology associated with loss of UCHL1 function, axonal swellings were detected in the striatum. In agreement with previously reported findings the loss of UCHL1 function was accompanied by perturbations in ubiquitin pools, but glutathione levels were also significantly depleted in the brains of the knockout mice, suggesting that oxidative defense mechanisms may be doubly compromised. To determine if, in addition to its role in the central nervous system, UCHL1 function is also required for homeostasis of the enteric nervous system the gastrointestinal tract was analyzed in UCHL1 knockout mice. The mice displayed functional changes and morphological changes in gut neurons that preceded degenerative changes in the brain. The changes were qualitatively and quantitatively similar to those observed in wild type mice of much greater age, and strongly resemble changes reported for elderly humans. UCHL1 knockout mice should therefore serve as a useful model of gut aging. PMID:24994982

  1. Age-related changes in the attentional control of visual cortex: A selective problem in the left visual hemifield

    PubMed Central

    Nagamatsu, Lindsay S.; Carolan, Patrick; Liu-Ambrose, Teresa Y.L.; Handy, Todd C.

    2012-01-01

    To what extent does our visual-spatial attention change with age? In this regard, it has been previously reported that relative to young controls, seniors show delays in attention-related sensory facilitation. Given this finding, our study was designed to examine two key questions regarding age-related changes in the effect of spatial attention on sensory-evoked responses in visual cortex –– are there visual field differences in the age-related impairments in sensory processing, and do these impairments co-occur with changes in the executive control signals associated with visual spatial orienting? Therefore, our study examined both attentional control and attentional facilitation in seniors (aged 66 to 74 years) and young adults (aged 18 to 25 years) using a canonical spatial orienting task. Participants responded to attended and unattended peripheral targets while we recorded event-related potentials (ERPs) to both targets and attention-directing spatial cues. We found that not only were sensory-evoked responses delayed in seniors specifically for unattended events in the left visual field as measured via latency shifts in the lateral occipital P1 elicited by visual targets, but seniors also showed amplitude reductions in the anterior directing attentional negativity (ADAN) component elicited by cues directing attention to the left visual field. At the same time, seniors also had significantly higher error rates for targets presented in the left vs. right visual field. Taken together, our data thus converge on the conclusion that age-related changes in visual spatial attention involve both sensory-level and executive attentional control processes, and that these effects appear to be strongly associated with the left visual field. PMID:21356222

  2. Age-Related Degenerative Functional, Radiographic, and Histological Changes of the Shoulder in Non-Human Primates

    PubMed Central

    Plate, Johannes F.; Bates, Christopher M.; Mannava, Sandeep; Smith, Thomas L.; Jorgensen, Matthew J.; Register, Thomas C.; Stehle, John R.; High, Kevin P.; Shively, Carol A.; Kaplan, Jay R.; Saul, Katherine R.; Tuohy, Christopher J.

    2013-01-01

    Background Non-human primates have similar shoulder anatomy and physiology compared to humans and may represent a previously underutilized model for shoulder research. This study sought to identify naturally occurring bony and muscular degeneration in the shoulder of non-human primates and to assess relationships between structural and functional aspects of the shoulder and measures of physical function of the animals. We hypothesized that age-related degenerative changes in the shoulders of non-human primates would resemble those observed in aging humans. Methods Middle-aged (n=5, ages 9.4 to 11.8 years) and elderly (n=6, ages 19.8 to 26.4 years) female vervet monkeys were studied for changes in mobility and shoulder function, and radiographic and histologic signs of age-related degeneration. Results Four out of six (4/6) elderly animals had degenerative changes of the glenoid compared to 0/5 of the middle-aged animals (p=0.005). Elderly animals had glenoid retroversion, decreased joint space, walked slower and spent less time climbing and hanging than middle-aged vervets (p<0.05). Physical mobility and shoulder function correlated with glenoid version angle (p<0.05). Supraspinatus muscles of elderly animals were less dense (p=0.001), had decreased fiber cross-sectional area (p<0.001), but similar amounts of nuclear material (p=0.085). Degenerative rotator cuff tears were not observed in any of the eleven animals. Discussion and Conclusion The vervet monkey naturally undergoes age-related functional, radiographic and histological changes of the shoulder and may qualify as an animal model for selected translational research of shoulder osteoarthritis. Level of evidence Basic Science Study, in-vivo Animal Model PMID:23352182

  3. Age-related changes in the neurophysiology of language in adults: relationship to regional cortical thinning and white matter microstructure.

    PubMed

    Kemmotsu, Nobuko; Girard, Holly M; Kucukboyaci, N Erkut; McEvoy, Linda K; Hagler, Donald J; Dale, Anders M; Halgren, Eric; McDonald, Carrie R

    2012-08-29

    Although reading skill remains relatively stable with advancing age in humans, neurophysiological measures suggest potential reductions in efficiency of lexical information processing. It is unclear whether these age-related changes are secondary to decreases in regional cortical thickness and/or microstructure of fiber tracts essential to language. Magnetoencephalography, volumetric MRI, and diffusion tensor imaging were performed in 10 young (18-33 years) and 10 middle-aged (42-64 years) human individuals to evaluate the spatiotemporal dynamics and structural correlates of age-related changes in lexical-semantic processing. Increasing age was associated with reduced activity in left temporal lobe regions from 250 to 350 ms and in left inferior prefrontal cortex from 350 to 450 ms (i.e., N400). Hierarchical regression indicated that age no longer predicted left inferior prefrontal activity after cortical thickness and fractional anisotropy (FA) of the uncinate fasciculus (UF) were considered. Interestingly, FA of the UF was a stronger predictor of the N400 response than cortical thickness. Age-related reductions in left-lateralization of language responses were observed between 250 and 350 ms, and were associated with left temporal thinning and frontotemporal FA reductions. N400 reductions were not associated with poorer task performance. Rather, increasing age was associated with reduction in the left prefrontal N400, which in turn was also associated with slower response time. These results reveal that changes in the neurophysiology of language occur by middle age and appear to be partially mediated by structural brain loss. These neurophysiological changes may reflect an adaptive process that ensues as communication between left perisylvian regions declines.

  4. Age-related changes in body composition in laboratory rats: Strain and gender comparisons

    EPA Science Inventory

    Long Evans (LE), Sprague Dawley (SD), Fischer 344 (F344), and Brown Norway (BN) rats are all commonly used as laboratory research subjects. These strains have been studied under many conditions, but few studies have measured changes in body composition as the animals age. Underst...

  5. Age-related changes in rat intrinsic laryngeal muscles: analysis of muscle fibers, muscle fiber proteins, and subneural apparatuses.

    PubMed

    Nishida, Naoya; Taguchi, Aki; Motoyoshi, Kazumi; Hyodo, Masamitsu; Gyo, Kiyofumi; Desaki, Junzo

    2013-03-01

    We compared age-related changes in the intrinsic laryngeal muscles of aged and young adult rats by determining the number and diameter of muscle fibers, contractile muscle protein (myosin heavy chain isoforms, MHC) composition, and the morphology of the subneural apparatuses. In aged rats, both the numbers and the diameters of muscle fibers decreased in the cricothyroid (CT) muscle. The number of fibers, but not diameter, decreased in the thyroarytenoid (TA) muscle. In the posterior cricoarytenoid (PCA) muscle, neither the number nor the diameter of fibers changed significantly. Aging was associated with a decrease in type IIB and an increase in type IIA MHC isoform levels in CT muscle, but no such changes were observed in the TA or PCA muscles. Morphological examination of primary synaptic clefts of the subneural apparatus revealed that aging resulted in decreased labyrinthine and increased depression types in only the CT muscle. In the aged group, morphologically immature subneural apparatuses were found infrequently in the CT muscle, indicating continued tissue remodeling. We suggest, therefore, that age-related changes in the intrinsic laryngeal muscles primarily involve the CT muscle, whereas the structures of the TA and PCA muscles may better resist aging processes and therefore are less vulnerable to functional impairment. This may reflect differences in their roles; the CT muscle controls the tone of the vocal folds, while the TA and PCA muscles play an essential role in vital activities such as respiration and swallowing.

  6. Age-related changes in the plasticity and toughness of human cortical bone at multiple length-scales

    SciTech Connect

    Zimmermann, Elizabeth A.; Schaible, Eric; Bale, Hrishikesh; Barth, Holly D.; Tang, Simon Y.; Reichert, Peter; Busse, Bjoern; Alliston, Tamara; Ager III, Joel W.; Ritchie, Robert O.

    2011-08-10

    The structure of human cortical bone evolves over multiple length-scales from its basic constituents of collagen and hydroxyapatite at the nanoscale to osteonal structures at nearmillimeter dimensions, which all provide the basis for its mechanical properties. To resist fracture, bone’s toughness is derived intrinsically through plasticity (e.g., fibrillar sliding) at structural-scales typically below a micron and extrinsically (i.e., during crack growth) through mechanisms (e.g., crack deflection/bridging) generated at larger structural-scales. Biological factors such as aging lead to a markedly increased fracture risk, which is often associated with an age-related loss in bone mass (bone quantity). However, we find that age-related structural changes can significantly degrade the fracture resistance (bone quality) over multiple lengthscales. Using in situ small-/wide-angle x-ray scattering/diffraction to characterize sub-micron structural changes and synchrotron x-ray computed tomography and in situ fracture-toughness measurements in the scanning electron microscope to characterize effects at micron-scales, we show how these age-related structural changes at differing size-scales degrade both the intrinsic and extrinsic toughness of bone. Specifically, we attribute the loss in toughness to increased non-enzymatic collagen cross-linking which suppresses plasticity at nanoscale dimensions and to an increased osteonal density which limits the potency of crack-bridging mechanisms at micron-scales. The link between these processes is that the increased stiffness of the cross-linked collagen requires energy to be absorbed by “plastic” deformation at higher structural levels, which occurs by the process of microcracking.

  7. Age-related changes in hematology and plasma chemistry values of hybrid striped bass (Morone chrysops X Morone saxatilis).

    PubMed

    Hrubec, Terry C.; Smith, Stephen A.; Robertson, John L.

    2001-01-01

    Hybrid striped bass (Morone chrysops X Morone saxatilis ) are an important aquaculture species yet there are few diagnostic tools available to assess their health. Hematology and clinical chemistry analyses are not used extensively in fish medicine due to the lack of reference intervals for various fish species, and because factors such as age can affect blood values. There is little published information regarding age-related changes in blood values of juvenile fish. It is important to evaluate juvenile fish, as this is the time they are raised in aquaculture settings. Determining age-related changes in the blood values of fishes would further develop clinical pathology as a diagnostic tool, enhancing both fish medicine and the aquaculture industry. The results of standard hematology and clinical chemistry analysis were evaluated in juvenile hybrid striped bass at 4, 6, 9, 15, and 19 months of age. Values for PCV and RBC indices were significantly lower, and plasma protein concentration was significantly higher in younger fish. Total WBC and lymphocyte counts were significantly higher in fish at 6 and 9 months of age, while neutrophil and monocyte counts were higher at 6, 9, and 15 months. Eosinophil counts were significantly higher in 9-month-old fish. The majority of hematologic values fell within previously established reference intervals, indicating that only slight modification to the intervals is necessary for evaluating hematologic results of hybrid striped bass at different ages. The following analytes deviated sufficiently from adult reference intervals to warrant separate reference values: plasma protein concentration at 4 months, WBC and lymphocyte counts at 15 and 19 months, and thrombocyte-like-cells at 9 months of age. Values for most biochemical analytes were significantly different among age groups except for creatinine and potassium concentrations. Comparisons with reference intervals were not made for biochemical analytes, because established

  8. Age-related changes in the kinetics of human lenses: prevention of the cataract

    PubMed Central

    Pescosolido, Nicola; Barbato, Andrea; Giannotti, Rossella; Komaiha, Chiara; Lenarduzzi, Fiammetta

    2016-01-01

    The crystalline lens is a transparent, biconvex structure in the eye that, along with the cornea, helps to refract light to be focused on the retina and, by changing shape, it adjusts focal distance (accommodation). The three classes of structural proteins found in the lens are α, β, and γ crystallins. These proteins make up more than 90% of the total dry mass of the eye lens. Other components which can be found are sugars, lipids, water, several antioxidants and low weight molecules. When ageing changes occur in the lens, it causes a gradual reduction in transparency, presbyopia and an increase in the scattering and aberration of light waves as well as a degradation of the optical quality of the eye. The main changes that occur with aging are: 1) reduced diffusion of water from the outside to the inside of the lens and from its cortical to its nuclear zone; 2) crystalline change due to the accumulation of high molecular weight aggregates and insoluble proteins; 3) production of advanced glycation end products (AGEs), lipid accumulation, reduction of reduced glutathione content and destruction of ascorbic acid. Even if effective strategies in preventing cataract onset are not already known, good results have been reached in some cases with oral administration of antioxidant substances such as caffeine, pyruvic acid, epigallocatechin gallate (EGCG), α-lipoic acid and ascorbic acid. Furthermore, methionine sulfoxide reductase A (MSRA) over expression could protect lens cells both in presence and in absence of oxidative stress-induced damage. Nevertheless, promising results have been obtained by reducing ultraviolet-induced oxidative damage. PMID:27803872

  9. Age-related and site-specific changes in the pulpodentinal morphology of rat molars.

    PubMed

    Lovschall, H; Fejerskov, O; Josephsen, K

    2002-05-01

    The rat molars are frequently used as experimental models in endodontic research, but there is little systematic information available on the influence of age on the pulpodentinal organ in Wistar rat molars and it is often difficult to evaluate more subtle changes following experimental interventions. The aim here was to describe changes with age in first upper Wistar rat molars with specific reference to the pulpodentinal organ. Animals were perfused with glutaraldehyde at 19 days, 1, 3, 6, 8, 12, 16, or 24 months of age. First upper molars from 56 animals were demineralized in EDTA, embedded in Epon, and processed for light and transmission electron microscopy. Substantial variation in the structure of the dentine and odontoblasts was observed within the root canals and the coronal pulp chamber. In general, odontoblasts changed from a tall, columnar morphology in the coronal pulp chamber to a more cuboidal or flattened shape near the apex, particularly towards the interradicular space. Secondary dentine formation was more pronounced along the mesial aspect of the root chamber and corresponding to the bottom of fissures. Local tertiary dentine formation was layered in the upper pulp chamber, corresponding to occlusal attrition of the cusp. In several molars a local formation of irregular tertiary dentine was observed cervically in the mesial pulp chamber. After 1 year, a distinct protrusion of irregular dentine extended into the mesiocervical pulp, apparently corresponding to a denudation of cervical root dentine. Experimental pulp-capping studies frequently use first upper rat molars with perforations made through the mesial aspect of the crown; such perforations might be close to the irregular dentine in the mesiocervical region. In conclusion, this study identifies age-associated and regional changes of pulpodentinal morphology in first upper rat molars. Therefore, evaluation of morphological alterations following vital-pulp experiments should be done in

  10. Age-related changes in tissue macrophages precede cardiac functional impairment.

    PubMed

    Pinto, Alexander R; Godwin, James W; Chandran, Anjana; Hersey, Lucy; Ilinykh, Alexei; Debuque, Ryan; Wang, Lina; Rosenthal, Nadia A

    2014-05-01

    Cardiac tissue macrophages (cTMs) are abundant in the murine heart but the extent to which the cTM phenotype changes with age is unknown. This study characterizes aging-dependent phenotypic changes in cTM subsets. Using theCx3cr1(GFP/+) mouse reporter line where GFP marks cTMs, and the tissue macrophage marker Mrc1, we show that two major cardiac tissue macrophage subsets, Mrc1-GFP(hi) and Mrc1+GFP(hi) cTMs, are present in the young (<10 week old) mouse heart, and a third subset, Mrc1+GFP(lo), comprises ~50% of total Mrc1+ cTMs from 30 weeks of age. Immunostaining and functional assays show that Mrc1+ cTMs are the principal myeloid sentinels in the mouse heart and that they retain proliferative capacity throughout life. Gene expression profiles of the two Mrc1+ subsets also reveal that Mrc1+GFP(lo) cTMs have a decreased number of immune response genes (Cx3cr1, Lpar6, CD9, Cxcr4, Itga6 and Tgfβr1), and an increased number of fibrogenic genes (Ltc4s, Retnla, Fgfr1, Mmp9 and Ccl24), consistent with a potential role for cTMs in cardiac fibrosis. These findings identify early age-dependent gene expression changes in cTMs, with significant implications for cardiac tissue injury responses and aging-associated cardiac fibrosis. PMID:24861132

  11. Effects of Geroprotectors on Age-Related Changes in Proteolytic Digestive Enzyme Activities at Different Lighting Conditions.

    PubMed

    Morozov, A V; Khizhkin, E A; Svechkina, E B; Vinogradova, I A; Ilyukha, V A; Anisimov, V N; Khavinson, V Kh

    2015-10-01

    We studied the effect of melatonin and epithalon on age-related changes in proteolytic digestive enzyme activity in the pancreas and gastric mucosa of rats kept under different lighting conditions. In rats kept under standard illumination, pepsin activity and the total proteolytic activity in the stomach and pancreas increased by the age of 12 months, but then decreased. Constant and natural lighting disturbed the age dynamics of proteolytic digestive enzyme activity. Administration of melatonin and epithalon to animals exposed to constant lighting restored age dynamics of pepsin activity and little affected total proteolytic activity.

  12. Endopolyploidy Changes with Age-Related Polyethism in the Honey Bee, Apis mellifera

    PubMed Central

    Rangel, Juliana; Strauss, Kim; Seedorf, Kaileah; Hjelmen, Carl E.; Johnston, J. Spencer

    2015-01-01

    Honey bees (Apis mellifera) exhibit age polyethism, whereby female workers assume increasingly complex colony tasks as they age. While changes in DNA methylation accompany age polyethism, other DNA modifications accompanying age polyethism are less known. Changes in endopolyploidy (DNA amplification in the absence of cell division) with increased larval age are typical in many insect cells and are essential in adults for creating larger cells, more copies of essential loci, or greater storage capacity in secretory cells. However, changes in endopolyploidy with increased adult worker age and polyethism are unstudied. In this study, we examined endopolyploidy in honey bee workers ranging in age from newly emerged up to 55 days old. We found a nonsignificant increase in ploidy levels with age (P < 0.1) in the most highly endopolyploid secretory cells, the Malpighian tubules. All other cell types decreased ploidy levels with age. Endopolyploidy decreased the least amount (nonsignificant) in neural (brain) cells and the stinger (P < 0.1). There was a significant reduction of endopolyploidy with age in leg (P < 0.05) and thoracic (P < 0.001) muscles. Ploidy in thoracic muscle dropped from an average of 0.5 rounds of replication in newly emerged workers to essentially no rounds of replication (0.125) in the oldest workers. Ploidy reduction in flight muscle cells is likely due to the production of G1 (2C) nuclei by amitotic division in the multinucleate striated flight muscles that are essential to foragers, the oldest workers. We suggest that ploidy is constrained by the shape, size and makeup of the multinucleate striated muscle cells. Furthermore, the presence of multiple 2C nuclei might be optimal for cell function, while higher ploidy levels might be a dead-end strategy of some aging adult tissues, likely used to increase cell size and storage capacity in secretory cells. PMID:25881205

  13. Salivary antimicrobial proteins associate with age-related changes in streptococcal composition in dental plaque.

    PubMed

    Malcolm, J; Sherriff, A; Lappin, D F; Ramage, G; Conway, D I; Macpherson, L M D; Culshaw, S

    2014-12-01

    Secretion of antimicrobial proteins (AMPs) and salivary antibodies can modify biofilm formation at host body surfaces. In adolescents, associations have been reported between dental caries and salivary AMPs. AMPs demonstrate direct antimicrobial effects at high concentrations, and at lower more physiological concentrations they mediate changes in host cell defenses, which may alter the local environment and indirectly shape local biofilm formation. The expression of salivary AMPs in preschool children, at an age when the oral bacteria are known to change, has not been investigated. We sought to investigate salivary AMP expression in the context of previously well-documented changes in the oral cavities of this age group including salivary immunoglobulin A (IgA), oral bacteria and dental caries. Dental plaque and saliva were collected from 57 children aged 12-24 months at baseline, of whom 23 children were followed-up at 3 years of age. At each time, saliva was assessed for LL37, human neutrophil peptides 1-3, calprotectin, lactoferrin, salivary IgA, total plaque bacteria and Streptococcus mutans. Over time, concentrations of AMPs, S. mutans and bacteria-specific salivary IgA increased. Caries experience was also recorded when children were 3 years old. Concentrations of AMPs were highest in the saliva of 3-year-old children with the greatest burden of S. mutans. These data suggest that salivary AMPs are variable over time and between individuals, and are linked with bacterial colonization. At follow up, the majority of children remained caries free. Larger longitudinal studies are required to confirm whether salivary AMP levels are predictive of caries and whether their modulation offers therapeutic benefit.

  14. Age-Related Change in Mobility: Perspectives From Life Course Epidemiology and Geroscience.

    PubMed

    Ferrucci, Luigi; Cooper, Rachel; Shardell, Michelle; Simonsick, Eleanor M; Schrack, Jennifer A; Kuh, Diana

    2016-09-01

    Mobility is the most studied and most relevant physical ability affecting quality of life with strong prognostic value for disability and survival. Natural selection has built the "engine" of mobility with great robustness, redundancy, and functional reserve. Efficient patterns of mobility can be acquired during development even by children affected by severe impairments. Analogously, age-associated impairments in mobility-related physiological systems are compensated and overt limitations of mobility only occur when the severity can no longer be compensated. Mobility loss in older persons usually results from multiple impairments in the central nervous system, muscles, joints, and energetic and sensory physiological systems. Early preclinical changes in these physiological systems that precede mobility loss have been poorly studied. Peak performance, rate of decline, compensatory behaviors, or subclinical deterioration of physiological resources may cumulatively influence both timing of mobility loss and chances of recovery, but their role as risk factors has not been adequately characterized. Understanding the natural history of these early changes and intervening on them would likely be the most effective strategy to reduce the burden of disability in the population. For example, young women with low bone peak mass could be counseled to start strength resistance exercise to reduce their high risk of developing osteoporosis and fracture later in life. Expanding this approach to other physiological domains requires collecting and interpreting data from life course epidemiological studies, establishing normative measures of mobility, physical function, and physical activity, and connecting them with life course trajectories of the mobility-relevant physiological domains. PMID:26975983

  15. Age-related changes in dating aggression in Spanish high school students.

    PubMed

    Fernández-González, Liria; O'Leary, K Daniel; Muñoz-Rivas, Marina Julia

    2014-04-01

    Prevention programs for dating partner aggression should be based on knowledge about when such aggression starts and how it changes. Given the very few studies regarding such trends, changes in physical, psychological, and sexual aggression against dating partners were examined in 14- to 20-year-old Spanish high school students (N = 2,016). Overall, psychological aggression increased linearly, whereas physical aggression had a negative quadratic association, peaking at 16 to 17 years for males and females. Sexual aggression was infrequent, but it spiked at age 16 for males. Although physical aggression diminished in late adolescence, injuries as a consequence of such aggression increased linearly for females, and they were also significantly higher for females (14.9%) than for males (3%) at ages 18 to 20 years. The findings support the hypothesis that dating physical aggression for males and females peaks during middle-to-late adolescence and shows a similar developmental pattern to other antisocial and criminal behaviors. Prevention of dating aggression, escalation of such aggression, and prevention of injury should consider developmental trends in dating aggression.

  16. Age-Related Change in Mobility: Perspectives From Life Course Epidemiology and Geroscience.

    PubMed

    Ferrucci, Luigi; Cooper, Rachel; Shardell, Michelle; Simonsick, Eleanor M; Schrack, Jennifer A; Kuh, Diana

    2016-09-01

    Mobility is the most studied and most relevant physical ability affecting quality of life with strong prognostic value for disability and survival. Natural selection has built the "engine" of mobility with great robustness, redundancy, and functional reserve. Efficient patterns of mobility can be acquired during development even by children affected by severe impairments. Analogously, age-associated impairments in mobility-related physiological systems are compensated and overt limitations of mobility only occur when the severity can no longer be compensated. Mobility loss in older persons usually results from multiple impairments in the central nervous system, muscles, joints, and energetic and sensory physiological systems. Early preclinical changes in these physiological systems that precede mobility loss have been poorly studied. Peak performance, rate of decline, compensatory behaviors, or subclinical deterioration of physiological resources may cumulatively influence both timing of mobility loss and chances of recovery, but their role as risk factors has not been adequately characterized. Understanding the natural history of these early changes and intervening on them would likely be the most effective strategy to reduce the burden of disability in the population. For example, young women with low bone peak mass could be counseled to start strength resistance exercise to reduce their high risk of developing osteoporosis and fracture later in life. Expanding this approach to other physiological domains requires collecting and interpreting data from life course epidemiological studies, establishing normative measures of mobility, physical function, and physical activity, and connecting them with life course trajectories of the mobility-relevant physiological domains.

  17. Age-related changes in executive control and their relationships with activity performance in handwriting.

    PubMed

    Rosenblum, Sara; Engel-Yeger, Batya; Fogel, Yael

    2013-04-01

    Deterioration in the frontal and prefrontal cortex associated with executive functions (EF) occurs with age and may be associated with changes in daily performance. The aim of the present study was to describe changes occurring with age in Executive Functions (EF) and handwriting activity, as well as to analyze relationships between age, EF and handwriting performance. The study population included 80 healthy participants (aged 31 to 76+) living in the community. After answering five questions about their writing habits, the participants completed the Behavioral Assessment of the Dysexecutive Syndrome (BADS). In addition, they performed a handwriting task on a digitizer included in the Computerized Penmanship Evaluation Tool (ComPET), which provides kinematic measures of the handwriting process. Significant differences were found between the four age groups for both EF and temporal and spatial handwriting measures. A series of regressions indicated that age predicted 35% of the variance of the BADS profile score (EF control) and 32% of the variance of in-air time while writing. The results of this study indicated age effect on both EF control and handwriting performance. Possible implications for further research and clinical evaluation and intervention are discussed. PMID:23558056

  18. Age-related changes in human vestibulo-ocular and optokinetic reflexes: Pseudorandom rotation tests

    NASA Technical Reports Server (NTRS)

    Peterka, R. J.; Black, F. O.; Schoenhoff, M. B.

    1989-01-01

    The dynamic response properties of horizontal vestibulo-ocular reflex (VOR) and optokinetic reflex (OKR) were characterized in 216 human subjects ranging in age from 7 to 81 years. The object of this cross-sectional study was to determine the effects of aging on VOR and OKR reflex dynamics, and to identify the distributions of parameters which describe VOR and OKR responses to pseudorandom stimuli in a putatively normal population. In general, VOR and OKR response parameters changed in a manner consistent with declining function with increasing age. For the VOR this was reflected in declining response amplitudes, although the magnitude of the decline was small relative to the variability of the data. For the OKR the lag time of the response, probably associated with the time required for visual information processing, increased linearly with age at a rate of about 1 ms per year.

  19. Age related changes in the bone tissue under conditions of hypokinesia

    NASA Technical Reports Server (NTRS)

    Podrushnyak, E. P.; Suslov, E. I.

    1980-01-01

    Microroentgenography of nine young people, aged 24-29, before and after hypokinesia (16-37 days strict bed rest), showed that the heel bone density of those with initially high bone density generally decreased and that of those with initially low bone density generally increased. X-ray structural analysis of the femurs of 25 corpses of accidentally killed healthy people, aged 18-70, data are presented and discussed, with the conclusion that the bone hydroxyapatite crystal structure stabilizes by ages 20 to 25, is stable from ages 25 to 60 and decreases in density after age 60. It is concluded that bone tissue structure changes, both with age, and in a comparatively short time in hypokinesia.

  20. Maternal inflammation linearly exacerbates offspring age-related changes of spatial learning and memory, and neurobiology until senectitude.

    PubMed

    Li, Xue-Wei; Cao, Lei; Wang, Fang; Yang, Qi-Gang; Tong, Jing-Jing; Li, Xue-Yan; Chen, Gui-Hai

    2016-06-01

    Maternal inflammation during pregnancy can elevate the risk of neurodegenerative disorders in offspring. However, how it affects age-related impairments of spatial learning and memory and changes in the neurobiological indictors in the offspring in later adulthood is still elusive. In this study, the CD-1 mice with maternal gestational inflammation due to receiving lipopolysaccharide (LPS, i.p. 50 or 25μg/kg) were divided into 3-, 12-, 18-, and 22-month-old groups. The spatial learning and memory were evaluated using a six-radial arm water maze and the levels of presynaptic proteins (synaptotagmin-1 and syntaxin-1) and histone acetylation (H3K9ac and H4K8ac) in the dorsal hippocampus were detected using the immunohistochemical method. The results indicated that there were significant age-related impairments of spatial learning and memory, decreased levels of H4K8ac, H3K9ac, and syntaxin-1, and increased levels of synaptotagmin-1 in the offspring mice from 12 months old to 22 months old compared to the same-age controls. Maternal LPS treatment significantly exacerbated the offspring impairments of spatial learning and memory, the reduction of H3K9ac, H4K8ac, and syntaxin-1, and the increment of synaptotagmin-1 from 12 months old to 22 months old compared to the same-age control groups. The changes in the neurobiological indicators significantly correlated with the impairments of spatial learning and memory. Furthermore, this correlation, besides the age and LPS-treatment effects, also showed a dose-dependent effect. Our results suggest that maternal inflammation during pregnancy could exacerbate age-related impairments of spatial learning and memory, and neurobiochemical indicators in the offspring CD-1 mice from midlife to senectitude.

  1. Henle Fiber Layer Phase Retardation Changes Associated With Age-Related Macular Degeneration

    PubMed Central

    VanNasdale, Dean A.; Elsner, Ann E.; Peabody, Todd D.; Kohne, Kimberly D.; Malinovsky, Victor E.; Haggerty, Bryan P.; Weber, Anke; Clark, Christopher A.; Burns, Stephen A.

    2015-01-01

    Purpose. To quantify and compare phase retardation amplitude and regularity associated with the Henle fiber layer (HFL) between nonexudative AMD patients and age-matched controls using scanning laser polarimetry (SLP) imaging. Methods. A scanning laser polarimeter was used to collect 15 × 15° macular-centered images in 25 patients with nonexudative AMD and 25 age-matched controls. Raw image data were used to compute macular phase retardation maps associated with the HFL. Consecutive, annular regions of interest from 0.5 to 3.0° eccentricity, centered on the fovea, were used to generate intensity profiles from phase retardation data and analyzed with two complementary techniques: a normalized second harmonic frequency (2f) of the fast Fourier Transform (FFT) analysis and a curve fitting analysis using a 2f sine function. Paired t-tests were used to compare the normalized 2f FFT magnitude at each eccentricity between the two groups, the eccentricity that yielded the maximum normalized 2f FFT between paired individuals across the two groups, and curve fitting RMS error at each eccentricity between the two groups. Results. Normalized 2f FFT components were lower in the AMD group at each eccentricity, with no difference between the two groups in the maximum normalized 2f FFT component eccentricity. The root-mean-square (RMS) error from curve fitting was significantly higher in the AMD group. Conclusions. Phase retardation changes in the central macula indicate loss and/or structural alterations to central cone photoreceptors in nonexudative AMD patients. Scanning laser polarimetry imaging is a noninvasive method for quantifying cone photoreceptor changes associated with central macular disease. PMID:25525166

  2. The age-related quantitative ultrastructural changes in pinealocytes of gerbils.

    PubMed

    Swietoslawski, Jacek

    1999-01-01

    OBJECTIVES. Relatively few ultrastructural studies of the pineal gland of aging animals have been published. The pineal gland of the gerbil is especially interesting in respect to aging because of its progressive calcification with age, and this species has been considered as an excellent model for research on aging. Therefore, the aim of the present study was to examine the quantitative ultrastructure of pinealocytes of the gerbil in three different age groups. METHODS. Three groups of animals were included in the study: 1-month-old, 3-month-old, and 14-month-old. Cross-sectional areas of the pinealocyte and its nucleus and relative volumes of the following cell organelles: mitochondria, lysosomes, Golgi apparatus, granular endoplasmic reticulum and calcareous concretions as well as the number of dense-core vesicles and "synaptic" ribbons were analyzed. RESULTS. No age-dependent changes were observed in the size of pinealocytes and their nuclei. The relative volume of mitochondria and the number of dense-core vesicles increased progressively with age, and that of lysosomes was lowest in the 1-month-old animals and increased at age of 3 and 14 months, whereas a decrease in the relative volume of granular endoplasmic reticulum was observed in 3- and 14-month-old gerbils in comparison with 1-month-old animals. No difference was observed in relative volume of Golgi apparatus and in the number of "synaptic" ribbons. The most striking change was observed in the formation of calcareous concretion within the pineal with age. The pineal gland of 1-month-old gerbils was essentially devoid of these structures, their number and size in 3-month-old animals were moderate, and increased dramatically in 14-month-old animals. CONCLUSION. The ultrastructural features of the gerbil pinealocyte in all examined age groups point to high metabolic activity of these cells. PMID:11458204

  3. Proteomic analyses of age related changes in A.BY/SnJ mouse hearts

    PubMed Central

    2013-01-01

    Background A.BY/SnJ mice are used to study pathological alterations in the heart due to enteroviral infections. Since age is a well-known factor influencing the susceptibility of mice to infection, response to stress and manifestation of cardiovascular diseases, the myocardial proteome of A.BY/SnJ mice aged 1 and 4 months was comparatively studied using two dimensional-differential in-gel electrophoresis (2D-DIGE) and liquid chromatography tandem mass spectrometry (LC-MS/MS). Results Complementary analyses by 2D-DIGE and gel-free LC-MS/MS revealed 96 distinct proteins displaying age associated alterations in their levels. Proteins related to protein transport, and transport chain, lipid metabolism and fatty acid transport showed significant changes in 4 months old mouse hearts compared to juvenile hearts. Proteins involved in lipid metabolism and transport were identified at significantly higher levels in older mice and dysregulation of proteins of the respiratory transport chain were observed. Conclusion The current proteomics study discloses age dependent changes occurring in the hearts already in young mice of the strain A.BY/SnJ. Besides alterations in protein transport, we provide evidence that a decrease of ATP synthase in murine hearts starts already in the first months of life, leading to well-known low expression levels manifested in old mice thereby raising the possibility of reduced energy supply. In the first few months of murine life this seems to be compensated by an increased lipid metabolism. The functional alterations described should be considered during experimental setups in disease related studies. PMID:23816347

  4. Age-related changes in the cellular, mechanical, and contractile properties of rat tail tendons.

    PubMed

    Lavagnino, Michael; Gardner, Keri; Arnoczky, Steven P

    2013-01-01

    Tendon laxity following injury, cyclic creep, or repair has been shown to alter the normal homeostasis of tendon cells, which can lead to degenerative changes in the extracellular matrix. While tendon cells have been shown to have an inherent contractile mechanism that gives them some ability to retighten lax tendons and reestablish a homeostatic cellular environment, the effect of age on this process is unknown. To determine the effect of aging on cell number, cell shape, and tensile modulus on tendons as well as the rate of cell-mediated contraction of lax tendons, tail tendon fascicles from 1-, 3-, and 12-month-old rats were analyzed. Aging results in a decrease (p < 0.001) in cell number per mm(2): 1 m (981 ± 119), 3 m (570 ± 108), and 12 m (453 ± 23), a more flattened (p < 0.001) cell nuclei shape and a higher (p < 0.001) tensile modulus (MPa) of the tendons: 1 m (291 ± 2), 3 m (527 ± 38), and 12 m (640 ± 102). Both the extent and rate of contraction over 7 days decreased with age (p = 0.007). This decrease in contraction rate with age correlates to the observed changes seen in aging tendons [increased modulus (r(2) = 0.95), decreased cell number (r(2) = 0.89)]. The ability of tendons to regain normal tension following injury or exercise-induced laxity is a key factor in the recovery of tendon function. The decreased contraction rate as a function of age observed in the current study may limit the ability of tendon cells to retighten lax tendons in older individuals. This, in turn, may place these structures at further risk for injury or altered function.

  5. Age-related Hearing Loss: GABA, Nicotinic Acetylcholine and NMDA Receptor Expression Changes in Spiral Ganglion Neurons of the Mouse

    PubMed Central

    Tang, Xiaolan; Zhu, Xiaoxia; Ding, Bo; Walton, Joseph P.; Frisina, Robert D.; Su, Jiping

    2014-01-01

    Age-related hearing loss – presbycusis – is the number one communication disorder and most prevalent neurodegenerative condition of our aged population. Although speech understanding in background noise is quite difficult for those with presbycusis, there are currently no biomedical treatments to prevent, delay or reverse this condition. A better understanding of the cochlear mechanisms underlying presbycusis will help lead to future treatments. Objectives of the present study were to investigate gamma-amino butyric acid A (GABAA) receptor subunit α1, nicotinic acetylcholine (nACh) receptor subunit β2, and N-methyl-D-aspartate (NMDA) receptor subunit NR1 mRNA and protein expression changes in spiral ganglion neurons of the CBA/CaJ mouse cochlea, that occur in age-related hearing loss, utilizing quantitative immunohistochemistry and semi-quantitative RT-PCR techniques. We found that auditory brainstem response (ABR) thresholds shifted over 40 dB from 3–48 kHz in old mice compared to young adults. DPOAE thresholds also shifted over 40 dB from 6–49 kHz in old mice, and their amplitudes were significantly decreased or absent in the same frequency range. Spiral ganglion neuron (SGN) density decreased with age in basal, middle and apical turns, and SGN density of the basal turn declined the most. A positive correlation was observed between SGN density and ABR wave 1 amplitude. mRNA and protein expression of GABAAR α1 and AChR β2 decreased with age in SGNs in the old mouse cochlea. mRNA and protein expression of NMDAR NR1 increased with age in SGNs of the old mice. These findings demonstrate that there are functionally-relevant age-related changes of GABAAR, nAChR, NMDAR expression in CBA mouse SGNs reflecting their degeneration, which may be related to functional changes in cochlear synaptic transmission with age, suggesting biological mechanisms for peripheral age-related hearing loss. PMID:24316061

  6. Age-related changes in modular organization of human brain functional networks.

    PubMed

    Meunier, David; Achard, Sophie; Morcom, Alexa; Bullmore, Ed

    2009-02-01

    Graph theory allows us to quantify any complex system, e.g., in social sciences, biology or technology, that can be abstractly described as a set of nodes and links. Here we derived human brain functional networks from fMRI measurements of endogenous, low frequency, correlated oscillations in 90 cortical and subcortical regions for two groups of healthy (young and older) participants. We investigated the modular structure of these networks and tested the hypothesis that normal brain aging might be associated with changes in modularity of sparse networks. Newman's modularity metric was maximised and topological roles were assigned to brain regions depending on their specific contributions to intra- and inter-modular connectivity. Both young and older brain networks demonstrated significantly non-random modularity. The young brain network was decomposed into 3 major modules: central and posterior modules, which comprised mainly nodes with few inter-modular connections, and a dorsal fronto-cingulo-parietal module, which comprised mainly nodes with extensive inter-modular connections. The mean network in the older group also included posterior, superior central and dorsal fronto-striato-thalamic modules but the number of intermodular connections to frontal modular regions was significantly reduced, whereas the number of connector nodes in posterior and central modules was increased.

  7. Age-related changes of muscle and plasma amino acids in healthy children.

    PubMed

    Hammarqvist, Folke; Angsten, Gertrud; Meurling, Staffan; Andersson, Kerstin; Wernerman, Jan

    2010-07-01

    The aim of the study was to explore if changes in muscle and plasma amino acid concentrations developed during growth and differed from levels seen in adults. The gradient and concentrations of free amino acids in muscle and plasma were investigated in relation to age in metabolic healthy children. Plasma and specimens from the abdominal muscle were obtained during elective surgery. The children were grouped into three groups (group 1: < 1 year, n = 8; group 2: 1-4 years, n = 13 and group 3: 5-15 years, n = 15). A reference group of healthy adults (21-38 years, n = 22) was included in their comparisons and reflected specific differences between children and adults. In muscle the concentrations of 8 out of 19 amino acids analysed increased with age, namely taurine, aspartate, threonine, alanine, valine, isoleucine, leucine, histidine, as well as the total sums of branched chain amino acids (BCAA), basic amino acids (BAA) and total sum of amino acids (P < 0.05). In plasma the concentrations of threonine, glutamine, valine, cysteine, methionine, leucine, lysine, tryptophane, arginine, BCAA, BAA and the essential amino acids correlated with age (P < 0.05). These results indicate that there is an age dependency of the amino acid pattern in skeletal muscle and plasma during growth.

  8. Age-related Changes in the Sleep-dependent Reorganization of Declarative Memories.

    PubMed

    Baran, Bengi; Mantua, Janna; Spencer, Rebecca M C

    2016-06-01

    Consolidation of declarative memories has been associated with slow wave sleep in young adults. Previous work suggests that, in spite of changes in sleep, sleep-dependent consolidation of declarative memories may be preserved with aging, although reduced relative to young adults. Previous work on young adults shows that, with consolidation, retrieval of declarative memories gradually becomes independent of the hippocampus. To investigate whether memories are similarly reorganized over sleep at the neural level, we compared functional brain activation associated with word pair recall following a nap and equivalent wake in young and older adults. SWS during the nap predicted better subsequent memory recall and was negatively associated with retrieval-related hippocampal activation in young adults. In contrast, in older adults there was no relationship between sleep and memory performance or with retrieval-related hippocampal activation. Furthermore, compared with young adults, postnap memory retrieval in older adults required strong functional connectivity of the hippocampus with the PFC, whereas there were no differences between young and older adults in the functional connectivity of the hippocampus following wakefulness. These results suggest that, although neural reorganization takes place over sleep in older adults, the shift is unique from that seen in young adults, perhaps reflecting memories at an earlier stage of stabilization.

  9. Age-related changes in the control of finger force vectors.

    PubMed

    Kapur, Shweta; Zatsiorsky, Vladimir M; Latash, Mark L

    2010-12-01

    We explored changes in finger interaction in the process of healthy aging as a window into neural control strategies of natural movements. In particular, we quantified the amount of force produced by noninstructed fingers in different directions, the amount of force produced by the instructed finger orthogonally to the task direction, and the strength of multifinger synergies stabilizing the total force magnitude and direction during accurate force production. Healthy elderly participants performed accurate isometric force production tasks in five directions by individual fingers and by all four fingers acting together. Their data were compared with a dataset obtained in a similar earlier study of young subjects. Finger force vectors were measured using six-component force/torque sensors. Multifinger synergies were quantified using the framework of the uncontrolled manifold hypothesis. The elderly participants produced lower force magnitudes by noninstructed fingers and higher force magnitudes by instructed fingers in nontask directions. They showed strong synergies stabilizing the magnitude and direction of the total force vector. However, the synergy indexes were significantly lower than those observed in the earlier study of young subjects. The results are consistent with an earlier hypothesis of preferential weakening of intrinsic hand muscles with age. We interpret the findings as a shift in motor control from synergic to element-based, which may be causally linked to the documented progressive neuronal death at different levels of the neural axis. PMID:20829494

  10. Age-related changes in the control of finger force vectors

    PubMed Central

    Kapur, Shweta; Zatsiorsky, Vladimir M.

    2010-01-01

    We explored changes in finger interaction in the process of healthy aging as a window into neural control strategies of natural movements. In particular, we quantified the amount of force produced by noninstructed fingers in different directions, the amount of force produced by the instructed finger orthogonally to the task direction, and the strength of multifinger synergies stabilizing the total force magnitude and direction during accurate force production. Healthy elderly participants performed accurate isometric force production tasks in five directions by individual fingers and by all four fingers acting together. Their data were compared with a dataset obtained in a similar earlier study of young subjects. Finger force vectors were measured using six-component force/torque sensors. Multifinger synergies were quantified using the framework of the uncontrolled manifold hypothesis. The elderly participants produced lower force magnitudes by noninstructed fingers and higher force magnitudes by instructed fingers in nontask directions. They showed strong synergies stabilizing the magnitude and direction of the total force vector. However, the synergy indexes were significantly lower than those observed in the earlier study of young subjects. The results are consistent with an earlier hypothesis of preferential weakening of intrinsic hand muscles with age. We interpret the findings as a shift in motor control from synergic to element-based, which may be causally linked to the documented progressive neuronal death at different levels of the neural axis. PMID:20829494

  11. Age-related changes in cellular electrophysiology and calcium handling for atrial fibrillation

    PubMed Central

    Xu, Guo-Jun; Gan, Tian-Yi; Tang, Bao-Peng; Chen, Zu-Heng; Jiang, Tao; Song, Jian-Guo; Guo, Xia; Li, Jin-xin

    2013-01-01

    This study was to investigate whether or not the dysfunction of atrial repolarization and abnormality of the intracellular Ca2+ handling protein was augmented with ageing. Four groups of dogs were studied, adult and aged dogs in sinus rhythm (SR) and atrial fibrillation (AF) induced by rapid atrial pacing. We used whole cell patch clamp recording techniques to measure L-type Ca2+ current in cardiomyocytes dispersed from the left atria. Expressions of the Ca2+ handling protein were measured by real-time quantitative reverse transcription-polymerase chain reaction and Western blot methods. Cardiomyocytes from old atria showed longer action potential (AP) duration to 90% repolarization, lower AP plateau potential and peak L-type Ca2+ current densities at both age groups in SR. AF led to a higher maximum diastolic potential, an increase of amplitude of phase 0, decreases of AP duration to 90% repolarization, plateau potential and peak L-type Ca2+ current densities. Compared to the adult group, mRNA and protein expressions of the L-type calcium channel a1c were decreased, whereas expressions of calcium adenosine triphosphatase were increased in the aged group. Compared to SR group, expressions of Ca2+ handling protein except for phospholamban were significantly decreased in both age groups with AF. We conclude that these ageing-induced electrophysiological and molecular changes showed that general pathophysiological adaptations might provide a substrate conducive to AF. PMID:23837844

  12. Age-Related Changes in Population of Stromal Precursor Cells in Hematopoietic and Lymphoid Organs.

    PubMed

    Gorskaya, Yulia F.; Latzinik, Natalia V.; Shuklina, Ekaterina U.; Nesterenko, Vladimir G.

    2000-07-01

    It is shown that the content of precursor cells of stromal tissue (CFC-F) in the hemopoietic and lymphoid organs of SAMP (rapidly-ageing mice) and SAMR mice (mice with a normal ageing rate) decreases as the animals grow older. However the decrease in the content of CFC-F in SAMP mice begins substantially earlier - in the age group of 9-11 months, while in the SAMR mice - only in the age group of 16-19 months. It was found that the age reduction of the number to an equal degree relates to the whole population of CFC-F, in particular both the fraction of weakly-linked CFC-F, which is isolated by means of mechanical disaggregation of the tissue, and the fraction which may only be isolated using trypsin. It is shown that the concentration of inducible osteogenic precursor cells (IOPC) in the spleen of guinea pigs does not change with age, but their content in that organ in old animals (2-3 years old) drops by two times. It was found that in elderly animals the mass of the ectopic osseous tissue, formed by the implantation of an osteoinductor (autologous epithelium of the urinary bladder) in a system open for entrance of cells, decreases by two times. After curettage of the medullary cavity of guinea pig tibia (i.e. under conditions of an increased demand for osteogenic cells) the mass of induced ectopic osseous tissue decreases by 4 times, which indicates to the possible functional relationship between the pool of determined and inducible osteogenic precursor cells. On the whole, the obtained data show that during ageing there is a reduction in the number of stromal precursor cells (CFC-F and IOPC), which form a specific microenvironment for hemopoietic and lymphoid organs, which is important to understand the role of these cells in the development of age pathologies, in particular senile osteoporosis. PMID:12687170

  13. Age-related changes of serum mitochondrial uncoupling 1, rumen and rectal temperature in goats.

    PubMed

    Arfuso, Francesca; Rizzo, Maria; Giannetto, Claudia; Giudice, Elisabetta; Fazio, Francesco; Piccione, Giuseppe

    2016-07-01

    Thermoregulatory processes are induced not only by exposure to cold or heat but also by a variety of physiological situations including age, fasting and food intake that result in changes in body temperature. The aim of the present study was to evaluate the differences in serum mitochondrial uncoupling protein 1 (UCP1), rumen temperature (TRUMEN) and rectal temperature (TRECTAL) values between adult and kids goats. Ten adult male Maltese goats aged 3-5 years old (Group A) and 30 male kids, raised for meat, were enrolled in this study. The kids were equally divided into 3 groups according to their age: Group B included kids aged 3 months, Group C included kids aged 4 months and Group D included kids aged 5 months. Blood samples and measurements of TRUMEN and TRECTAL were obtained from each animal. One-way repeated measures analysis of variance (ANOVA) was applied to evaluate the effect of age on the studied parameters. Statistically significant higher serum UCP1 levels (P<0.001) were found in Group A as compared to Groups B, C and D. Higher TRUMEN values (P<0.001) were found in Group A than in Groups B, C and D, and in Group B than in Groups C and D. Group A showed lower TRECTAL values (P<0.001) than Groups B, C and D. The Pearson's Correlation test was applied to assess significant relationship among studied parameters showing a statistically significant negative correlation between the values of TRECTAL and serum UCP1 in all studied Groups (P<0.001). These results indicate that goats have good control of body temperature suggesting that further details about the thermogenic capacity and the function of UCP1 in kids and adult goats are worth exploring. PMID:27264887

  14. Selenosugar and trimethylselenonium among urinary Se metabolites: dose- and age-related changes

    SciTech Connect

    Suzuki, Kazuo T. . E-mail: ktsuzuki@p.chiba-u.ac.jp; Kurasaki, Kazuki; Okazaki, Natsuko; Ogra, Yasumitsu

    2005-08-01

    Once selenium (Se) is absorbed by the body, it is excreted mostly into the urine and the major metabolite is 1{beta}-methylseleno-N-acetyl-D-galactosamine (selenosugar) within the required to low-toxic range. Selenosugar plateaus with a dose higher than 2.0 {mu}g Se/ml water or g diet, and trimethylselenonium (TMSe) starts to increase, indicating that TMSe can be a biomarker of excessive and toxic doses of Se. Here, we show dose-related changes in the two urinary Se metabolites to clarify the relationship between the dose and urinary metabolites by feeding selenite to rats. It was also examined whether the metabolites are related to age, and further whether a possible exogenous source of the N-acetyl-D-galactosamine moiety, chondroitin 4-sulfate, affects the urinary metabolites. Selenite in drinking water was fed ad libitum to male Wistar rats of 36 and 5 weeks of age, and the concentrations of Se in the urine and organs were determined together with speciation of the urinary Se metabolites. In young rats, selenosugar was always the major urinary metabolite and TMSe increased with a dose higher than 2.0 {mu}g Se/ml drinking water. On the other hand, in adult rats, TMSe increased only marginally despite that the rats suffered much more greatly from the Se toxicity, suggesting that TMSe cannot be a biomarker of Se toxicity. The results suggest that sources of the sugar moiety of selenosugar are more abundant in adult rats than in young rats. Chondroitin 4-sulfate did not affect the ratio of the two urinary metabolites, suggesting that the sugar source is of endogenous origin and that it increases with age.

  15. Age-related changes of serum mitochondrial uncoupling 1, rumen and rectal temperature in goats.

    PubMed

    Arfuso, Francesca; Rizzo, Maria; Giannetto, Claudia; Giudice, Elisabetta; Fazio, Francesco; Piccione, Giuseppe

    2016-07-01

    Thermoregulatory processes are induced not only by exposure to cold or heat but also by a variety of physiological situations including age, fasting and food intake that result in changes in body temperature. The aim of the present study was to evaluate the differences in serum mitochondrial uncoupling protein 1 (UCP1), rumen temperature (TRUMEN) and rectal temperature (TRECTAL) values between adult and kids goats. Ten adult male Maltese goats aged 3-5 years old (Group A) and 30 male kids, raised for meat, were enrolled in this study. The kids were equally divided into 3 groups according to their age: Group B included kids aged 3 months, Group C included kids aged 4 months and Group D included kids aged 5 months. Blood samples and measurements of TRUMEN and TRECTAL were obtained from each animal. One-way repeated measures analysis of variance (ANOVA) was applied to evaluate the effect of age on the studied parameters. Statistically significant higher serum UCP1 levels (P<0.001) were found in Group A as compared to Groups B, C and D. Higher TRUMEN values (P<0.001) were found in Group A than in Groups B, C and D, and in Group B than in Groups C and D. Group A showed lower TRECTAL values (P<0.001) than Groups B, C and D. The Pearson's Correlation test was applied to assess significant relationship among studied parameters showing a statistically significant negative correlation between the values of TRECTAL and serum UCP1 in all studied Groups (P<0.001). These results indicate that goats have good control of body temperature suggesting that further details about the thermogenic capacity and the function of UCP1 in kids and adult goats are worth exploring.

  16. In vivo study of age-related changes in the optical properties of the skin.

    PubMed

    Calin, Mihaela Antonina; Parasca, S V

    2010-03-01

    The optical properties of the skin (absorption coefficient, scattering coefficient, refractive index) may serve to characterize the skin and are important for correct light dosimetry in many optical diagnostic procedures and laser treatments especially photodynamic therapy and laser therapy. We determined in vivo the optical properties of tissues near the wrist, elbow and knee in subjects of different ages using diffuse reflectance spectroscopy, having in view the establishment of laser system types for the laser treatment of posttraumatic lesions in subjects of different ages. Diffuse reflection of light from biological tissue is due to the variation in refractive index of tissular and cellular components and the surrounding medium and depends on the wavelength of the incident optical radiation. The diffuse reflectance spectrum of the tissues tested showed two maxima localized at lamda(M1) is approximately 610 nm and lambda(M2) is approximately 675 nm. Laser systems which emit radiation at these wavelengths are not efficient for the treatment of joints, regardless of the subject's age. The deep tissues have a strong absorption in the range 630-700 nm, which indicates that for treating posttraumatic lesions we can use laser systems such as the He-Ne laser, the GaAlAs laser, and the InGaAlAs laser. Using Kramers-Kronig analysis of the diffuse reflectance spectra, the optical parameters n(omega) and k(omega) were determined. The age-dependent changes in these optical parameters of tissue must be taken into consideration and the use of laser treatments or optical diagnosis methods must be based on a knowledge of these properties and of the optical radiation parameters.

  17. Age-related cognitive decline and electroencephalogram slowing in Down's syndrome as a model of Alzheimer's disease.

    PubMed

    Soininen, H; Partanen, J; Jousmäki, V; Helkala, E L; Vanhanen, M; Majuri, S; Kaski, M; Hartikainen, P; Riekkinen, P

    1993-03-01

    We studied quantitative electroencephalogram and neuropsychological performance in an aging series of 31 patients with Down's syndrome and compared the findings with those of 36 patients with probable Alzheimer's disease and age-matched controls. We found an age-related decline of cortical functions and slowing of the electroencephalogram in Down's syndrome patients aged from 20 to 60 years. Slowing of the electroencephalogram, i.e. the decrease of the peak frequency, was significantly related to Mini-Mental status scores, and visual, praxic and speech functions, as well as memory in the Down patients, similar to the Alzheimer patients. Similar correlations were not demonstrated for young or elderly controls. This study provides neuropsychological and electrophysiological data to suggest that studying Down's syndrome patients of different ages can serve as a model for progression of Alzheimer's disease. PMID:8469312

  18. Age-related kinematic changes in late visual-cueing during obstacle circumvention.

    PubMed

    Paquette, Maxime R; Vallis, Lori Ann

    2010-06-01

    On a daily basis, we are challenged by common environmental obstacles (e.g. street posts) that require simple and often rapid modifications to our gait patterns to avoid collisions. Poor vision appears to be responsible for important reductions in postural stability during gait; and therefore, individuals with impaired vision, such as the elderly, may be at a greater risk of falling, especially under conditions where stepping avoidance strategies may be constrained by the environment. The purpose of the current study was to examine the body segment and eye-gaze reorientation strategy, role of base of support, as well as visual areas of interest attended to by healthy young (YA) and older adults (OA) when only given limited time, one stride, to prepare for an obstacle circumvention task. Six YA and six OA were asked to perform ten walking trials which required them to circumvent an obstacle in their travel path. Participants used one of two avoidance strategies, either lead leg crossing-over trail leg (narrow base of support) or lead leg stepping-out (wide base of support). Results indicate that base of support constraints did not affect segment reorientation sequence in either age group. The general segment reorientation sequence in YA was initiated by trunk yaw and head yaw, followed by gaze and finally, by M-L foot deviation. No trunk roll deviations were observed. In OA, the general segment reorientation sequence was the following: trunk yaw and trunk roll, gaze and finally, M-L foot deviation. No head yaw deviations were observed. Our findings suggest that YA utilized a foot placement strategy to perform the transient change in travel direction while OA relied on a hip strategy. In addition, YA spent more time gazing straight ahead at the obstacle and the wall, while OA spent more time looking at the ground. This strategy indicates that OA use a more cautious strategy to safely avoid the obstacle. Findings from the present work contribute further knowledge

  19. Using the gradient of human cortical bone properties to determine age-related bone changes via ultrasonic guided waves.

    PubMed

    Baron, Cécile

    2012-06-01

    Bone fragility depends not only on bone mass but also on bone quality (structure and material). To accurately evaluate fracture risk or propose therapeutic treatment, clinicians need a criterion, which reflects the determinants of bone strength: geometry, structure and material. In human long bone, the changes due to aging, accentuated by osteoporosis are often revealed through the trabecularization of cortical bone, i.e., increased porosity of endosteal bone inducing a thinning of the cortex. Consequently, the intracortical porosity gradient corresponding to the spatial variation in porosity across the cortical thickness is representative of loss of mass, changes in geometry (thinning) and variations in structure (porosity). This article examines the gradient of material properties and its age-related evolution as a relevant parameter to assess bone geometry, structure and material. By applying a homogenization process, cortical bone can be considered as an anisotropic functionally graded material with variations in material properties. A semi-analytical method based on the sextic Stroh formalism is proposed to solve the wave equation in an anisotropic functionally graded waveguide for two geometries, a plate and a tube, without using a multilayered model to represent the structure. This method provides an analytical solution called the matricant and explicitly expressed under the Peano series expansion form. Our findings indicate that ultrasonic guided waves are sensitive to the age-related evolution of realistic gradients in human bone properties across the cortical thickness and have their place in a multimodal clinical protocol.

  20. Age-Related Changes following In Vitro Stimulation with Rhodococcus equi of Peripheral Blood Leukocytes from Neonatal Foals

    PubMed Central

    Kachroo, Priyanka; Ivanov, Ivan; Seabury, Ashley G.; Liu, Mei; Chowdhary, Bhanu P.; Cohen, Noah D.

    2013-01-01

    Rhodococcus equi is an intracellular bacterium primarily known as an equine pathogen that infects young foals causing a pyogranulomatuous pneumonia. The molecular mechanisms mediating the immune response of foals to R. equi are not fully elucidated. Hence, global genomic high-throughput tools like gene expression microarrays might identify age-related gene expression signatures and molecular pathways that contribute to the immune mechanisms underlying the inherent susceptibility of foals to disease caused by R. equi. The objectives of this study were 2-fold: 1) to compare the expression profiles at specific ages of blood leukocytes from foals stimulated with virulent R. equi with those of unstimulated leukocytes; and, 2) to characterize the age-related changes in the gene expression profile associated with blood leukocytes in response to stimulation with virulent R. equi. Peripheral blood leukocytes were obtained from 6 foals within 24 hours (h) of birth (day 1) and 2, 4, and 8 weeks after birth. The samples were split, such that half were stimulated with live virulent R. equi, and the other half served as unstimulated control. RNA was extracted and the generated cDNA was labeled with fluorescent dyes for microarray hybridizations using an equine microarray. Our findings suggest that there is age-related differential expression of genes involved in host immune response and immunity. We found induction of genes critical for host immunity against pathogens (MHC class II) only at the later time-points (compared to birth). While it appears that foals up to 8-weeks of age are able to initiate a protective inflammatory response against the bacteria, relatively decreased expression of various other immune-related genes points toward inherent diminished immune responses closer to birth. These genes and pathways may contribute to disease susceptibility in foals if infected early in life, and might thus be targeted for developing preventative or therapeutic strategies. PMID

  1. Age-Related Cognitive Impairment as a Sign of Geriatric Neurocardiovascular Interactions: May Polyphenols Play a Protective Role?

    PubMed Central

    Jagla, Fedor; Pechanova, Olga

    2015-01-01

    It is known that endothelial dysfunction plays an important role in the development and progression of cardiovascular diseases implicated also in cognitive decline. Experimental studies pointed to the fact that the modification of NO levels via NOS activity may affect the blood pressure level as well as several higher nervous functions—for example, learning and memory. There are emerging evidences from in vitro and animal studies suggesting that polyphenols may potentially have a protective effect on the development of neurodegenerative diseases and may improve cognitive function as well as positively affecting the blood pressure regulatory mechanisms. This review accentuates the need for precisely defined clinically controlled studies as well as for use of adequate experimental procedures discriminating between the human higher brain functions and the only overall activation of the brain cortex. The physiological neurocardiovascular interactions are implicated in the increased healthy life span as well. PMID:26180593

  2. Age-related changes in anterior cingulate cortex glutamate in schizophrenia: A (1)H MRS Study at 7 Tesla.

    PubMed

    Brandt, Allison S; Unschuld, Paul G; Pradhan, Subechhya; Lim, Issel Anne L; Churchill, Gregory; Harris, Ashley D; Hua, Jun; Barker, Peter B; Ross, Christopher A; van Zijl, Peter C M; Edden, Richard A E; Margolis, Russell L

    2016-04-01

    The extent of age-related changes in glutamate and other neurometabolites in the anterior cingulate cortex (ACC) in individuals with schizophrenia remain unclear. Magnetic resonance spectroscopy (MRS) at 7 T, which yields precise measurements of various metabolites and can distinguish glutamate from glutamine, was used to determine levels of ACC glutamate and other metabolites in 24 individuals with schizophrenia and 24 matched controls. Multiple regression analysis revealed that ACC glutamate decreased with age in patients but not controls. No changes were detected in levels of glutamine, N-acetylaspartate, N-acetylaspartylglutamic acid, myo-inositol, GABA, glutathione, total creatine, and total choline. These results suggest that age may be an important modifier of ACC glutamate in schizophrenia. PMID:26925800

  3. Age-related changes in miR-143-3p:Igfbp5 interactions affect muscle regeneration.

    PubMed

    Soriano-Arroquia, Ana; McCormick, Rachel; Molloy, Andrew P; McArdle, Anne; Goljanek-Whysall, Katarzyna

    2016-04-01

    A common characteristic of aging is defective regeneration of skeletal muscle. The molecular pathways underlying age-related decline in muscle regenerative potential remain elusive. microRNAs are novel gene regulators controlling development and homeostasis and the regeneration of most tissues, including skeletal muscle. Here, we use satellite cells and primary myoblasts from mice and humans and an in vitro regeneration model, to show that disrupted expression of microRNA-143-3p and its target gene, Igfbp5, plays an important role in muscle regeneration in vitro. We identified miR-143 as a regulator of the insulin growth factor-binding protein 5 (Igfbp5) in primary myoblasts and show that the expression of miR-143 and its target gene is disrupted in satellite cells from old mice. Moreover, we show that downregulation of miR-143 during aging may act as a compensatory mechanism aiming at improving myogenesis efficiency; however, concomitant upregulation of miR-143 target gene, Igfbp5, is associated with increased cell senescence, thus affecting myogenesis. Our data demonstrate that dysregulation of miR-143-3p:Igfbp5 interactions in satellite cells with age may be responsible for age-related changes in satellite cell function. PMID:26762731

  4. Characteristics of age-related behavioral changes in senescence-accelerated mouse SAMP8 and SAMP10.

    PubMed

    Miyamoto, M

    1997-01-01

    Senescence-Accelerated Mouse (SAM), a murine model of accelerated senescence, has been established by Takeda et al. (1981). SAM consists of senescence-accelerated-prone mouse (SAMP) and senescence-accelerated-resistant mouse (SAMR), the latter of which shows normal aging characteristics. In 1991 there were eight different substrains in the P-series, which commonly exhibited accelerated aging with a shortened life span (Takeda et al., 1991). Among the P-series, we have found that SAMP8 mice show significant impairments in a variety of learning tasks when compared with SAMR1 mice (Miyamoto et al., 1986). Further studies suggest that SAMP8 exhibits an age-related emotional disorder characterized by reduced anxiety-like behavior (Miyamoto et al., 1992). On the other hand, it has been shown that SAMP10 exhibits brain atrophy and learning impairments in an avoidance task (Shimada et al., 1992, 1993). Here, characteristics of age-related deficits in learning and memory, changes in emotional behavior, and abnormality of circadian rhythms in SAMP8 and SAMP10 mice are described. In the experiments, SAMP8/Ta (SAMP8), SAMP10/(/)Ta (SAMP10) and SAMR1TA (SAMR1) reared under specific pathogen-free conditions at Takeda Chemical Industries were used. PMID:9088911

  5. Age-related changes in the brain antioxidant status: modulation by dietary supplementation of Decalepis hamiltonii and physical exercise.

    PubMed

    Ravikiran, Tekupalli; Sowbhagya, Ramachandregowda; Anupama, Sindhghatta Kariyappa; Anand, Santosh; Bhagyalakshmi, Dundaiah

    2016-08-01

    The synergistic effects of physical exercise and diet have profound benefits on brain function. The present study was aimed to determine the effects of exercise and Decalepis hamiltonii (Dh) on age-related responses on the antioxidant status in discrete regions of rat brain. Male Wistar albino rats of 4 and 18 months old were orally supplemented with Dh extract and swim trained at 3 % intensity for 30 min/day, 5 days/week, for a period of 30 days. Supplementation of 100 mg Dh aqueous extract/kg body weight and its combination with exercise significantly elevated the antioxidant enzyme activities irrespective of age. Age-related and region-specific changes were observed in superoxide levels, and protein carbonyl and malondialdehyde contents, and were found to be decreased in both trained and supplemented groups. Levels of total thiols, protein, and nonprotein thiols decreased with age and significantly increased in the SW-T(+100 mg) groups. Our results demonstrated that the interactive effects of two treatments enhanced the antioxidant status and decreased the risk of protein and lipid oxidation in the rat brain. PMID:27379504

  6. Age-related hearing loss: aquaporin 4 gene expression changes in the mouse cochlea and auditory midbrain.

    PubMed

    Christensen, Nathan; D'Souza, Mary; Zhu, Xiaoxia; Frisina, Robert D

    2009-02-01

    Presbycusis -- age-related hearing loss, is the number one communication disorder, and one of the top three chronic medical conditions of our aged population. Aquaporins, particularly aquaporin 4 (Aqp4), are membrane proteins with important roles in water and ion flux across cell membranes, including cells of the inner ear and pathways of the brain used for hearing. To more fully understand the biological bases of presbycusis, 39 CBA mice, a well-studied animal model of presbycusis, underwent non-invasive hearing testing as a function of sound frequency (auditory brainstem response -- ABR thresholds, and distortion-product otoacoustic emission -- DPOAE magnitudes), and were clustered into four groups based on age and hearing ability. Aqp4 gene expression, as determined by genechip microarray analysis and quantitative real-time PCR, was compared to the young adult control group in the three older groups: middle aged with good hearing, old age with mild presbycusis, and old age with severe presbycusis. Linear regression and ANOVA showed statistically significant changes in Aqp4 gene expression and ABR and DPOAE hearing status in the cochlea and auditory midbrain -- inferior colliculus. Down-regulation in the cochlea was seen, and an initial down-, then up-regulation was discovered for the inferior colliculus Aqp4 expression. It is theorized that these changes in Aqp4 gene expression represent an age-related disruption of ion flux in the fluids of the cochlea that are responsible for ionic gradients underlying sound transduction in cochlear hair cells necessary for hearing. In regard to central auditory processing at the level of the auditory midbrain, aquaporin gene expression changes may affect neurotransmitter cycling involving supporting cells, thus impairing complex sound neural processing with age.

  7. Polarization sensitive changes in the human macula associated with normal aging and age-related macular degeneration

    NASA Astrophysics Data System (ADS)

    VanNasdale, Dean Allan, Jr.

    2011-12-01

    The human macula occupies a relatively small, but crucial retinal area, as it is the location responsible for our most acute spatial vision and best color discrimination. Localizing important landmarks in the retina is difficult even in normal eyes where morphological inter-individual variability is high. This becomes even more challenging in the presence of sight-threatening pathology. With respect to the human macula, there remains a significant gap in the understanding of normal structure and function. Even less is known about the pathological mechanisms that occur in sight-threatening diseases including age-related macular degeneration. Because relatively little is known about normal aging changes, it is also difficult to differentiate those changes from changes associated with retinal disease. To better understand normal and pathological changes in the macula, imaging techniques using specific optical signatures are required. Structural features in the macula can be distinguished based on their intrinsic properties using specific light/tissue interactions. Because of the high degree of structural regularity in the macula, polarization sensitive imaging is potentially a useful tool for evaluating the morphology and integrity of the cellular architecture for both normal individuals and those affected by disease. In our investigations, we used polarization sensitive imaging to determining normal landmarks that are important clinically and for research investigations. We found that precision and accuracy in localizing the central macula was greatly improved through the use of polarization sensitive imaging. We also found that specific polarization alterations can be used to demonstrate systematic changes as a function of age, disproportionately affecting the central macular region. When evaluating patients with age-related macular degeneration, we found that precision and accuracy of localizing the central macula was also improved, even when significant pathology

  8. Age-related changes in the content of the C-terminal region of aggrecan in human articular cartilage.

    PubMed Central

    Dudhia, J; Davidson, C M; Wells, T M; Vynios, D H; Hardingham, T E; Bayliss, M T

    1996-01-01

    The content of the C-terminal region of aggrecan was investigated in samples of articular cartilage from individuals ranging in age from newborn to 65 years. This region contains the globular G3 domain which is known to be removed from aggrecan in mature cartilage, probably by proteolytic cleavage, but the age-related changes in its abundance in human cartilage have not been described previously. The analysis was performed by immunosorbant assay using an antiserum (JD5) against recombinant amino acid residues of human aggrecan, on crude extracts of cartilage without further purification of aggrecan. The results showed that the content of the C-terminal region decreased with age relative to the G1 domain content (correlation coefficient = 0.463). This represented a 92% fall in the content of this region of the molecule from newborn to 65 years of age. furthermore, when the G1 content of the cartilage extracts was corrected to only include the G1 attached to aggrecan and to exclude the G1 fragments which accumulate as a by-product of normal aggrecan turnover (free G1), the age-related decrease in the C-terminal region remained very pronounced. Analysis by composite agarose/PAGE showed that the number of subpopulations of aggrecan resolved increased from one in newborn to three in adult cartilage. All of these reacted with an antiserum to the human G1 domain, but only the slowest migrating species reacted with the C-terminal region antiserum (JD5). Similar analysis by SDS/PAGE confirmed the presence of high-molecular-mass (200 kDa) proteins reactive with JD5, but no reactive fragments of lower electrophoretic mobility were detected. In contrast, when probed with the antiserum to the human G1 domain, the immunoblots showed protein species corresponding to the free G1 and G1-G2 fragments, which were present at high concentrations in adult cartilage. The results suggest that the loss of the C-terminal region is not directly part of the process of aggrecan turnover, but

  9. Discovering novel microRNAs and age-related nonlinear changes in rat brains using deep sequencing.

    PubMed

    Yin, Lanxuan; Sun, Yubai; Wu, Jinfeng; Yan, Siyu; Deng, Zhenglu; Wang, Jun; Liao, Shenke; Yin, Dazhong; Li, Guolin

    2015-02-01

    Elucidating the molecular mechanisms of brain aging remains a significant challenge for biogerontologists. The discovery of gene regulation by microRNAs (miRNAs) has added a new dimension for examining this process; however, the full complement of miRNAs involved in brain aging is still not known. In this study, miRNA profiles of young, adult, and old rats were obtained to evaluate molecular changes during aging. High-throughput deep sequencing revealed 547 known and 171 candidate novel miRNAs that were differentially expressed among groups. Unexpectedly, miRNA expression did not decline progressively with advancing age; moreover, genes targeted by age-associated miRNAs were predicted to be involved in biological processes linked to aging and neurodegenerative diseases. These findings provide novel insight into the molecular mechanisms underlying brain aging and a resource for future studies on age-related brain disorders.

  10. Tocopherol-mediated modulation of age-related changes in microglial cells: turnover of extracellular oxidized protein material.

    PubMed

    Stolzing, Alexandra; Widmer, Rebecca; Jung, Tobias; Voss, Peter; Grune, Tilman

    2006-06-15

    Proteins accumulate during aging and form insoluble protein aggregates. Microglia are responsible for their removal from the brain. During aging, changes within the microglia might play a crucial role in the malfunctioning of these cells. Therefore, we isolated primary microglial cells from adult rats and compared their activation status and their ability to degrade proteins to that of microglial cells isolated from newborn animals. The ability of adult microglial cells to degrade proteins is substantially decreased. However, the preincubation of microglial cells with vitamin E improves significantly the degradation of such modified proteins. The degradation of proteins from apoptotic vesicles is decreased in microglia isolated from adult rats. This might be the result of a suppression of the CD36 receptor due to vitamin E treatment. We concluded that microglial cells isolated from adult organisms have different metabolic properties and seem to be a more valuable model to study age-related diseases.

  11. Autism Spectrum Disorder in Children and Adolescents with Fragile X Syndrome: Within-Syndrome Differences and Age-Related Changes

    PubMed Central

    McDuffie, Andrea; Abbeduto, Leonard; Lewis, Pamela; Kim, Jee-Seon; Kover, Sara T.; Weber, Ann; Brown, W. Ted

    2010-01-01

    The Autism Diagnostic Interview-Revised was used to examine diagnostic profiles and age-related changes in autism symptoms for a group of verbal children and adolescents with FXS, with and without autism. After controlling for nonverbal IQ, statistically significant between-group differences for lifetime and current autism symptoms were found for the Communication and Restricted Interests/Repetitive Behaviors domains, but not the Reciprocal Social Interaction domain. Effect sizes for differences in Reciprocal Social Interaction also were smaller than effect sizes for the other domains with one exception. Overall, severity of autism symptoms improved with age for all participants, with the least improvement noted for Restricted Interests and Repetitive Behaviors. FMRP did not account for unique variance in autism symptoms over and above nonverbal IQ. PMID:20567604

  12. Long-term ginsenoside Rg1 supplementation improves age-related cognitive decline by promoting synaptic plasticity associated protein expression in C57BL/6J mice.

    PubMed

    Yang, Lumeng; Zhang, Jing; Zheng, Kunmu; Shen, Hui; Chen, Xiaochun

    2014-03-01

    In aging individuals, age-related cognitive decline is the most common cause of memory impairment. Among the remedies, ginsenoside Rg1, a major active component of ginseng, is often recommended for its antiaging effects. However, its role in improving cognitive decline during normal aging remains unknown and its molecular mechanism partially understood. This study employed a scheme of Rg1 supplementation for female C57BL/6J mice, which started at the age of 12 months and ended at 24 months, to investigate the effects of Rg1 supplementation on the cognitive performance. We found that Rg1 supplementation improved the performance of aged mice in behavior test and significantly upregulated the expression of synaptic plasticity-associated proteins in hippocampus, including synaptophysin, N-methyl-D-aspartate receptor subunit 1, postsynaptic density-95, and calcium/calmodulin-dependent protein kinase II alpha, via promoting mammalian target of rapamycin pathway activation. These data provide further support for Rg1 treatment of cognitive degeneration during aging.

  13. Age-related changes in meat tenderness and tissue pentosidine: effect of diet restriction and aminoguanidine in broiler breeder hens.

    PubMed

    Iqbal, M; Kenney, P B; Klandorf, H

    1999-09-01

    The nonenzymatic glycosylation of tissue protein contributes to the formation of crosslinks that leads to structural and functional deterioration in the long-lived tissue protein, collagen. The accumulation of these crosslinks thus contributes to the objectionable toughness of meat from aged animals, decreases its economic value, and limits its use in whole muscle foods. The objectives of this study were to determine the effectiveness of diet restriction and the crosslinking inhibitor, aminoguanidine (AG), on reducing the accumulation of crosslinks, thereby improving meat tenderness in broiler breeder hens. The glycoxidation product, pentosidine, was also measured in skin (Ps) to determine whether changes in its concentrations correlated with the changes in shear value (SV). Chicks (n = 450) were randomly assigned to four treatment groups from 8 to 125 wk after hatch: ad libitum (AL), diet restricted (DR), AL and DR groups supplemented with 400 ppm AG each (AL+AG and DR+AG, respectively). Shear value was measured with an Instron Universal Mechanical Machine. Skin pentosidine was isolated by reverse phase HPLC. There was an age-related, linear increase in SV (P<0.0001, r = 0.96), which correlated (r = 0.86) with the age-related increase in Ps in AL hens. Diet restriction retarded SV (P<0.0001) over the sampling period. In general, SV values for AL+AG were similar to those measured in DR, whereas no additive effect was observed for AG in DR birds. It was concluded that there was a linear increase in meat toughness (SV) with age that correlates with the accumulation of Ps, and that the decline in meat tenderness can be retarded by DR or AG. Secondly, the effect of DR on accumulation of Ps was so pronounced that AG supplementation did not further enhance this effect.

  14. Age-related changes in the morphology and protein expression of the thymus of healthy yaks (Bos grunniens).

    PubMed

    Zhang, Qian; Yang, Kun; Yangyang, Pan; He, Junfeng; Yu, Sijiu; Cui, Yan

    2016-06-01

    OBJECTIVE To evaluate age-related changes in the morphology and expression of cluster of differentiation 3 (CD3), S100 β, and caspase-3 of the thymus of healthy yaks (Bos grunniens). ANIMALS 15 healthy male yaks of various ages from highland plateaus. PROCEDURES Yaks were allocated to 3 groups on the basis of age (newborn [1 to 7 days old; n = 5], juvenile [5 to 7 months old, 5], and adult [3 to 4 years old; 5]) and euthanized. The thymus was harvested from each yak within 10 minutes after euthanasia. Morphological characteristics were assessed by histologic examination and transmission electron microscopy. Expression of CD3, S100 β, and caspase-3 mRNA and protein was measured by quantitative real-time PCR assay, Western blot analysis, and immunohistochemical staining. RESULTS As age increased, functional thymic tissue was replaced with adipose and connective tissues and the thymic capsule thickened. Expression of CD3 and S100 β mRNA and protein decreased with age, whereas expression of caspase-3 mRNA and protein increased with age. Immunohistochemical staining revealed that CD3-positive thymocytes were located within both the thymic cortex and medulla, S100 β-positive thymic dendritic cells were located in the corticomedullary junction and medulla, and caspase-3-positive thymocytes were diffusely scattered throughout the cortex and medulla. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that age-related thymic changes in yaks that live on highland plateaus were similar to those observed in humans and other mammals. Thus, yaks might serve as a model to study thymic immune system adaptations to high elevations. PMID:27227493

  15. Age-Related Changes in Antioxidant and Glutathione S-Transferase Enzyme Activities in the Asian Clam.

    PubMed

    Vranković, J

    2016-03-01

    Aging is accompanied by increased production of free oxygen radicals and impairment of normal cellular functions. The aim of this work was to provide preliminary data on age-related differences in the activities of antioxidant enzymes and phase II biotransformation enzyme glutathione S-transferase (GST) in a wild population of the Asian clam Corbicula fluminea. The antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR), and GST were assessed in visceral mass of four age classes (0+-, 1+-, 2+-, and 3+-year-old) of C. fluminea clams. Age-related changes were seen in antioxidant enzyme status: levels of total SOD (totSOD) (P < 0.05), MnSOD, and CuZnSOD (P < 0.05) activities increased progressively during aging from younger to older clams. Changes in CAT and GR activities with advancing age were found, the levels being the highest in age class II, then being lower in age classes III and IV (P < 0.05). Activities of GPX and GST were lower in the senescent individuals (2+- and 3+-year-old clams) compared with young individuals (0+- and 1+-year-old clams). Overall, the decline of glutathione-dependent enzyme activities, coupled with higher and lower activities of totSOD and CAT, respectively, as the individual grows older, may render the older animals more susceptible to oxidative stress. Data reported here are not intended to be exhaustive since they concern only age/size structure of the population at one locality, so more detailed studies on both the developmental stages and levels of antioxidant enzymes of this new alien species in Serbian rivers are required. PMID:27262191

  16. Gene Expression Changes for Antioxidants Pathways in the Mouse Cochlea: Relations to Age-related Hearing Deficits

    PubMed Central

    Tadros, Sherif F.; D'Souza, Mary; Zhu, Xiaoxia; Frisina, Robert D.

    2014-01-01

    Age-related hearing loss – presbycusis – is the number one neurodegenerative disorder and top communication deficit of our aged population. Like many aging disorders of the nervous system, damage from free radicals linked to production of reactive oxygen and/or nitrogen species (ROS and RNS, respectively) may play key roles in disease progression. The efficacy of the antioxidant systems, e.g., glutathione and thioredoxin, is an important factor in pathophysiology of the aging nervous system. In this investigation, relations between the expression of antioxidant-related genes in the auditory portion of the inner ear – cochlea, and age-related hearing loss was explored for CBA/CaJ mice. Forty mice were classified into four groups according to age and degree of hearing loss. Cochlear mRNA samples were collected and cDNA generated. Using Affymetrix® GeneChip, the expressions of 56 antioxidant-related gene probes were analyzed to estimate the differences in gene expression between the four subject groups. The expression of Glutathione peroxidase 6, Gpx6; Thioredoxin reductase 1, Txnrd1; Isocitrate dehydrogenase 1, Idh1; and Heat shock protein 1, Hspb1; were significantly different, or showed large fold-change differences between subject groups. The Gpx6, Txnrd1 and Hspb1 gene expression changes were validated using qPCR. The Gpx6 gene was upregulated while the Txnrd1 gene was downregulated with age/hearing loss. The Hspb1 gene was found to be downregulated in middle-aged animals as well as those with mild presbycusis, whereas it was upregulated in those with severe presbycusis. These results facilitate development of future interventions to predict, prevent or slow down the progression of presbycusis. PMID:24587312

  17. Gene expression changes for antioxidants pathways in the mouse cochlea: relations to age-related hearing deficits.

    PubMed

    Tadros, Sherif F; D'Souza, Mary; Zhu, Xiaoxia; Frisina, Robert D

    2014-01-01

    Age-related hearing loss - presbycusis - is the number one neurodegenerative disorder and top communication deficit of our aged population. Like many aging disorders of the nervous system, damage from free radicals linked to production of reactive oxygen and/or nitrogen species (ROS and RNS, respectively) may play key roles in disease progression. The efficacy of the antioxidant systems, e.g., glutathione and thioredoxin, is an important factor in pathophysiology of the aging nervous system. In this investigation, relations between the expression of antioxidant-related genes in the auditory portion of the inner ear - cochlea, and age-related hearing loss was explored for CBA/CaJ mice. Forty mice were classified into four groups according to age and degree of hearing loss. Cochlear mRNA samples were collected and cDNA generated. Using Affymetrix® GeneChip, the expressions of 56 antioxidant-related gene probes were analyzed to estimate the differences in gene expression between the four subject groups. The expression of Glutathione peroxidase 6, Gpx6; Thioredoxin reductase 1, Txnrd1; Isocitrate dehydrogenase 1, Idh1; and Heat shock protein 1, Hspb1; were significantly different, or showed large fold-change differences between subject groups. The Gpx6, Txnrd1 and Hspb1 gene expression changes were validated using qPCR. The Gpx6 gene was upregulated while the Txnrd1 gene was downregulated with age/hearing loss. The Hspb1 gene was found to be downregulated in middle-aged animals as well as those with mild presbycusis, whereas it was upregulated in those with severe presbycusis. These results facilitate development of future interventions to predict, prevent or slow down the progression of presbycusis.

  18. Age-related changes in the effects of stress in pregnancy on infant motor development by maternal report: The Queensland Flood Study.

    PubMed

    Simcock, Gabrielle; Kildea, Sue; Elgbeili, Guillaume; Laplante, David P; Stapleton, Helen; Cobham, Vanessa; King, Suzanne

    2016-07-01

    The current study examined the effects of a natural disaster (a sudden onset flood) as a stressor in pregnancy on infant fine and gross motor development at 2, 6, and 16 months of age. Whether the timing of the stressor in pregnancy or sex of the infant moderated the impact of the prenatal maternal stress on motor development was also explored. Mothers' objective experiences of the flood, emotional reactions and distress, and their cognitive appraisal of the event were assessed retrospectively. Infants' fine and gross motor skills were assessed with the Ages and Stages Questionnaire, and results showed age-related changes in the effects of prenatal maternal stress on these domains. At 2 months, higher levels of prenatal maternal stress was positively related to infant motor development, yet at 6 and 16 months of age there was a negative association, particularly if flood exposure occurred later in pregnancy and if mothers had negative cognitive appraisals of the event. Results also showed differential effects of the maternal stress responses to the floods on infants' fine and gross motor development at each age and that infant sex did not buffer these effects. © 2016 Wiley Periodicals, Inc. Dev Psychobiol 58: 640-659, 2016. PMID:27004939

  19. Circadian regulation of human sleep and age-related changes in its timing, consolidation and EEG characteristics.

    PubMed

    Dijk, D J; Duffy, J F

    1999-04-01

    The light-entrainable circadian pacemaker located in the suprachiasmatic nucleus of the hypothalamus regulates the timing and consolidation of sleep by generating a paradoxical rhythm of sleep propensity; the circadian drive for wakefulness peaks at the end of the day spent awake, ie close to the onset of melatonin secretion at 21.00-22.00 h and the circadian drive for sleep crests shortly before habitual waking-up time. With advancing age, ie after early adulthood, sleep consolidation declines, and time of awakening and the rhythms of body temperature, plasma melatonin and cortisol shift to an earlier clock hour. The variability of the phase relationship between the sleep-wake cycle and circadian rhythms increases, and in old age sleep is more susceptible to internal arousing stimuli associated with circadian misalignment. The propensity to awaken from sleep advances relative to the body temperature nadir in older people, a change that is opposite to the phase delay of awakening relative to internal circadian rhythms associated with morningness in young people. Age-related changes do not appear to be associated with a shortening of the circadian period or a reduction of the circadian drive for wake maintenance. These changes may be related to changes in the sleep process itself, such as reductions in slow-wave sleep and sleep spindles as well as a reduced strength of the circadian signal promoting sleep in the early morning hours. Putative mediators and modulators of circadian sleep regulation are discussed. PMID:10344586

  20. Circadian regulation of human sleep and age-related changes in its timing, consolidation and EEG characteristics

    NASA Technical Reports Server (NTRS)

    Dijk, D. J.; Duffy, J. F.

    1999-01-01

    The light-entrainable circadian pacemaker located in the suprachiasmatic nucleus of the hypothalamus regulates the timing and consolidation of sleep by generating a paradoxical rhythm of sleep propensity; the circadian drive for wakefulness peaks at the end of the day spent awake, ie close to the onset of melatonin secretion at 21.00-22.00 h and the circadian drive for sleep crests shortly before habitual waking-up time. With advancing age, ie after early adulthood, sleep consolidation declines, and time of awakening and the rhythms of body temperature, plasma melatonin and cortisol shift to an earlier clock hour. The variability of the phase relationship between the sleep-wake cycle and circadian rhythms increases, and in old age sleep is more susceptible to internal arousing stimuli associated with circadian misalignment. The propensity to awaken from sleep advances relative to the body temperature nadir in older people, a change that is opposite to the phase delay of awakening relative to internal circadian rhythms associated with morningness in young people. Age-related changes do not appear to be associated with a shortening of the circadian period or a reduction of the circadian drive for wake maintenance. These changes may be related to changes in the sleep process itself, such as reductions in slow-wave sleep and sleep spindles as well as a reduced strength of the circadian signal promoting sleep in the early morning hours. Putative mediators and modulators of circadian sleep regulation are discussed.

  1. Prevalence of Age-Related Changes in Ovine Lumbar Intervertebral Discs during Computed Tomography and Magnetic Resonance Imaging.

    PubMed

    Nisolle, Jean-François; Bihin, Benoît; Kirschvink, Nathalie; Neveu, Fabienne; Clegg, Peter; Dugdale, Alexandra; Wang, Xiaoqing; Vandeweerd, Jean-Michel

    2016-01-01

    Ovine models are used to study intervertebral disc (IVD) degeneration. The objective of the current study was to assess the naturally occurring age-related changes of the IVD that can be diagnosed by CT and MRI in the lumbar spine of sheep. We used CT and T2-weighted MR images to score the IVD (L6S1 to L1L2) in 41 sheep (age, 6 mo to 11 y) that were euthanized for reasons not related to musculoskeletal disease. T2 mapping and measurement of T2 time of L6S1 to L2L3 were performed in 22 of the sheep. Degenerative changes manifested as early as 2 y of age and occurred at every IVD level. Discs were more severely damaged in older sheep. The age effect of the L6S1 IVD was larger than the average age effect for the other IVD. The current study provides evidence that lesions similar to those encountered in humans can be identified by CT and MRI in lumbar spine of sheep. Ideally, research animals should be assessed at the initiation of preclinical trials to determine the extent of prevalent degenerative changes. The ovine lumbosacral disc seems particularly prone to degeneration and might be a favorable anatomic site for studying IVD degeneration.

  2. Pairing Cholinergic Enhancement with Perceptual Training Promotes Recovery of Age-Related Changes in Rat Primary Auditory Cortex

    PubMed Central

    Voss, Patrice; Thomas, Maryse; Chou, You Chien; Cisneros-Franco, José Miguel; Ouellet, Lydia; de Villers-Sidani, Etienne

    2016-01-01

    We used the rat primary auditory cortex (A1) as a model to probe the effects of cholinergic enhancement on perceptual learning and auditory processing mechanisms in both young and old animals. Rats learned to perform a two-tone frequency discrimination task over the course of two weeks, combined with either the administration of a cholinesterase inhibitor or saline. We found that while both age groups learned the task more quickly through cholinergic enhancement, the young did so by improving target detection, whereas the old did so by inhibiting erroneous responses to nontarget stimuli. We also found that cholinergic enhancement led to marked functional and structural changes within A1 in both young and old rats. Importantly, we found that several functional changes observed in the old rats, particularly those relating to the processing and inhibition of nontargets, produced cortical processing features that resembled those of young untrained rats more so than those of older adult rats. Overall, these findings demonstrate that combining auditory training with neuromodulation of the cholinergic system can restore many of the auditory cortical functional deficits observed as a result of normal aging and add to the growing body of evidence demonstrating that many age-related perceptual and neuroplastic changes are reversible. PMID:27057359

  3. Prevalence of Age-Related Changes in Ovine Lumbar Intervertebral Discs during Computed Tomography and Magnetic Resonance Imaging.

    PubMed

    Nisolle, Jean-François; Bihin, Benoît; Kirschvink, Nathalie; Neveu, Fabienne; Clegg, Peter; Dugdale, Alexandra; Wang, Xiaoqing; Vandeweerd, Jean-Michel

    2016-01-01

    Ovine models are used to study intervertebral disc (IVD) degeneration. The objective of the current study was to assess the naturally occurring age-related changes of the IVD that can be diagnosed by CT and MRI in the lumbar spine of sheep. We used CT and T2-weighted MR images to score the IVD (L6S1 to L1L2) in 41 sheep (age, 6 mo to 11 y) that were euthanized for reasons not related to musculoskeletal disease. T2 mapping and measurement of T2 time of L6S1 to L2L3 were performed in 22 of the sheep. Degenerative changes manifested as early as 2 y of age and occurred at every IVD level. Discs were more severely damaged in older sheep. The age effect of the L6S1 IVD was larger than the average age effect for the other IVD. The current study provides evidence that lesions similar to those encountered in humans can be identified by CT and MRI in lumbar spine of sheep. Ideally, research animals should be assessed at the initiation of preclinical trials to determine the extent of prevalent degenerative changes. The ovine lumbosacral disc seems particularly prone to degeneration and might be a favorable anatomic site for studying IVD degeneration. PMID:27538861

  4. Sensorimotor and cognitive factors associated with the age-related increase of visual field dependence: a cross-sectional study.

    PubMed

    Agathos, Catherine P; Bernardin, Delphine; Huchet, Delphine; Scherlen, Anne-Catherine; Assaiante, Christine; Isableu, Brice

    2015-08-01

    Reliance on the visual frame of reference for spatial orientation (or visual field dependence) has been reported to increase with age. This has implications on old adults' daily living tasks as it affects stability, attention, and adaptation capacities. However, the nature and underlying mechanisms of this increase are not well defined. We investigated sensorimotor and cognitive factors possibly associated with increased visual field dependence in old age, by considering functions that are both known to degrade with age and important for spatial orientation and sensorimotor control: reliance on the (somatosensory-based) egocentric frame of reference, visual fixation stability, and attentional processing of complex visual scenes (useful field of view, UFOV). Twenty young, 18 middle-aged, and 20 old adults completed a visual examination, three tests of visual field dependence (RFT, RDT, and GEFT), a test of egocentric dependence (subjective vertical estimation with the body erect and tilted at 70°), a visual fixation task, and a test of visual attentional processing (UFOV®). Increased visual field dependence with age was associated with reduced egocentric dependence, visual fixation stability, and visual attentional processing. In addition, visual fixation instability and reduced UFOV were correlated. Results of middle-aged adults fell between those of the young and old, revealing the progressive nature of the age effects we evaluated. We discuss results in terms of reference frame selection with respect to ageing as well as visual and non-visual information processing. Inter-individual differences amongst old adults are highlighted and discussed with respect to the functionality of increased visual field dependence.

  5. Age-related changes in cerebellar and hypothalamic function accompany non-microglial immune gene expression, altered synapse organization, and excitatory amino acid neurotransmission deficits

    PubMed Central

    Bonasera, Stephen J.; Arikkath, Jyothi; Boska, Michael D.; Chaudoin, Tammy R.; DeKorver, Nicholas W.; Goulding, Evan H.; Hoke, Traci A.; Mojtahedzedah, Vahid; Reyelts, Crystal D.; Sajja, Balasrinivasa; Schenk, A. Katrin; Tecott, Laurence H.; Volden, Tiffany A.

    2016-01-01

    We describe age-related molecular and neuronal changes that disrupt mobility or energy balance based on brain region and genetic background. Compared to young mice, aged C57BL/6 mice exhibit marked locomotor (but not energy balance) impairments. In contrast, aged BALB mice exhibit marked energy balance (but not locomotor) impairments. Age-related changes in cerebellar or hypothalamic gene expression accompany these phenotypes. Aging evokes upregulation of immune pattern recognition receptors and cell adhesion molecules. However, these changes do not localize to microglia, the major CNS immunocyte. Consistent with a neuronal role, there is a marked age-related increase in excitatory synapses over the cerebellum and hypothalamus. Functional imaging of these regions is consistent with age-related synaptic impairments. These studies suggest that aging reactivates a developmental program employed during embryogenesis where immune molecules guide synapse formation and pruning. Renewed activity in this program may disrupt excitatory neurotransmission, causing significant behavioral deficits. PMID:27689748

  6. Age related increase in mTOR activity contributes to the pathological changes in ovarian surface epithelium

    PubMed Central

    Bajwa, Preety; Nagendra, Prathima B.; Nielsen, Sarah; Sahoo, Subhransu S.; Bielanowicz, Amanda; Lombard, Janine M.; Wilkinson, Erby J.; Miller, Richard A.; Tanwar, Pradeep S.

    2016-01-01

    Ovarian cancer is a disease of older women. However, the molecular mechanisms of ovarian aging and their contribution to the pathogenesis of ovarian cancer are currently unclear. mTOR signalling is a major regulator of aging as suppression of this pathway extends lifespan in model organisms. Overactive mTOR signalling is present in up to 80% of ovarian cancer samples and is associated with poor prognosis. This study examined the role of mTOR signalling in age-associated changes in ovarian surface epithelium (OSE). Histological examination of ovaries from both aged mice and women revealed OSE cell hyperplasia, papillary growth and inclusion cysts. These pathological lesions expressed bonafide markers of ovarian cancer precursor lesions, Pax8 and Stathmin 1, and were presented with elevated mTOR signalling. To understand whether overactive mTOR signalling is responsible for the development of these pathological changes, we analysed ovaries of the Pten trangenic mice and found significant reduction in OSE lesions compared to controls. Furthermore, pharmacological suppression of mTOR signalling significantly decreased OSE hyperplasia in aged mice. Treatment with mTOR inhibitors reduced human ovarian cancer cell viability, proliferation and colony forming ability. Collectively, we have established the role of mTOR signalling in age-related OSE pathologies and initiation of ovarian cancer. PMID:27036037

  7. Age related increase in mTOR activity contributes to the pathological changes in ovarian surface epithelium.

    PubMed

    Bajwa, Preety; Nagendra, Prathima B; Nielsen, Sarah; Sahoo, Subhransu S; Bielanowicz, Amanda; Lombard, Janine M; Wilkinson, J Erby; Miller, Richard A; Tanwar, Pradeep S

    2016-04-12

    Ovarian cancer is a disease of older women. However, the molecular mechanisms of ovarian aging and their contribution to the pathogenesis of ovarian cancer are currently unclear. mTOR signalling is a major regulator of aging as suppression of this pathway extends lifespan in model organisms. Overactive mTOR signalling is present in up to 80% of ovarian cancer samples and is associated with poor prognosis. This study examined the role of mTOR signalling in age-associated changes in ovarian surface epithelium (OSE). Histological examination of ovaries from both aged mice and women revealed OSE cell hyperplasia, papillary growth and inclusion cysts. These pathological lesions expressed bonafide markers of ovarian cancer precursor lesions, Pax8 and Stathmin 1, and were presented with elevated mTOR signalling. To understand whether overactive mTOR signalling is responsible for the development of these pathological changes, we analysed ovaries of the Pten trangenic mice and found significant reduction in OSE lesions compared to controls. Furthermore, pharmacological suppression of mTOR signalling significantly decreased OSE hyperplasia in aged mice. Treatment with mTOR inhibitors reduced human ovarian cancer cell viability, proliferation and colony forming ability. Collectively, we have established the role of mTOR signalling in age-related OSE pathologies and initiation of ovarian cancer.

  8. Influence of metabolic syndrome on arterial stiffness and its age-related change in young adults: the Bogalusa Heart Study.

    PubMed

    Li, Shengxu; Chen, Wei; Srinivasan, Sathanur R; Berenson, Gerald S

    2005-06-01

    Increased arterial stiffness is associated with risk variables of metabolic syndrome in middle-aged and older adults. However, information regarding the influence of the metabolic syndrome on arterial stiffness and its rate of change with age in young adults is limited. These aspects were examined in a sample of 806 asymptomatic, healthy young adults aged 24-44 years from a black-white community. Brachial to ankle pulse wave velocity (baPWV) measured by an oscillometric method was used as an index of arterial stiffness. baPWV increased with the increasing number of metabolic syndrome components, defined by National Cholesterol Education Program Adult Treatment Panel III (1256, 1314, and 1422 cm/s for those with 0, 1-2, and 3-5 components, respectively, P for trend <0.001). Furthermore, the rate of change (slope) of baPWV with age increased as the number of metabolic syndrome components increased (4.1, 10.7, and 18.7 cm/s per year for those with 0, 1-2, and 3-5 components, respectively; P for comparison of slopes <0.001). These findings by showing the deleterious effects of metabolic syndrome on arterial stiffness and its age-related increase in young adults underscore the importance of this syndrome in cardiovascular risk assessment even in a younger population. Further longitudinal studies are needed to confirm the current cross-sectional findings.

  9. Litter size, age-related memory impairments, and microglial changes in rat dentate gyrus: stereological analysis and three dimensional morphometry.

    PubMed

    Viana, L C; Lima, C M; Oliveira, M A; Borges, R P; Cardoso, T T; Almeida, I N F; Diniz, D G; Bento-Torres, J; Pereira, A; Batista-de-Oliveira, M; Lopes, A A C; Silva, R F M; Abadie-Guedes, R; Amâncio Dos Santos, A; Lima, D S C; Vasconcelos, P F C; Cunningham, C; Guedes, R C A; Picanço-Diniz, C W

    2013-05-15

    It has been demonstrated that rat litter size affects the immune cell response, but it is not known whether the long-term effects aggravate age-related memory impairments or microglial-associated changes. To that end, we raised sedentary Wistar rats that were first suckled in small or large litters (6 or 12pups/dam, respectively), then separated into groups of 2-3 rats from the 21st post-natal day to study end. At 4months (young adult) or 23months (aged), all individual rats were submitted to spatial memory and object identity recognition tests, and then sacrificed. Brain sections were immunolabeled with anti-IBA-1 antibodies to selectively identify microglia/macrophages. Microglial morphological changes in the molecular layer of the dentate gyrus were estimated based on three-dimensional reconstructions. The cell number and laminar distribution in the dentate gyrus was estimated with the stereological optical fractionator method. We found that, compared to young rat groups, aged rats from large litters showed significant increases in the number of microglia in all layers of the dentate gyrus. Compared to the microglia in all other groups, microglia in aged individuals from large litters showed a significantly higher degree of tree volume expansion, branch base diameter thickening, and cell soma enlargement. These morphological changes were correlated with an increase in the number of microglia in the molecular layer. Young adult individuals from small litters exhibited preserved intact object identity recognition memory and all other groups showed reduced performance in both spatial and object identity recognition tasks. We found that, in large litters, brain development was, on average, associated with permanent changes in the innate immune system in the brain, with a significant impact on the microglial homeostasis of aged rats.

  10. Age-Related Changes in BOLD Activation Pattern in Phonemic Fluency Paradigm: An Investigation of Activation, Functional Connectivity and Psychophysiological Interactions

    PubMed Central

    La, Christian; Garcia-Ramos, Camille; Nair, Veena A.; Meier, Timothy B.; Farrar-Edwards, Dorothy; Birn, Rasmus; Meyerand, Mary E.; Prabhakaran, Vivek

    2016-01-01

    Healthy aging is associated with decline of cognitive functions. However, even before those declines become noticeable, the neural architecture underlying those mechanisms has undergone considerable restructuring and reorganization. During performance of a cognitive task, not only have the task-relevant networks demonstrated reorganization with aging, which occurs primarily by recruitment of additional areas to preserve performance, but the task-irrelevant network of the “default-mode” network (DMN), which is normally deactivated during task performance, has also consistently shown reduction of this deactivation with aging. Here, we revisited those age-related changes in task-relevant (i.e., language system) and task-irrelevant (i.e., DMN) systems with a language production paradigm in terms of task-induced activation/deactivation, functional connectivity, and context-dependent correlations between the two systems. Our task fMRI data demonstrated a late increase in cortical recruitment in terms of extent of activation, only observable in our older healthy adult group, when compared to the younger healthy adult group, with recruitment of the contralateral hemisphere, but also other regions from the network previously underutilized. Our middle-aged individuals, when compared to the younger healthy adult group, presented lower levels of activation intensity and connectivity strength, with no recruitment of additional regions, possibly reflecting an initial, uncompensated, network decline. In contrast, the DMN presented a gradual decrease in deactivation intensity and deactivation extent (i.e., low in the middle-aged, and lower in the old) and similar gradual reduction of functional connectivity within the network, with no compensation. The patterns of age-related changes in the task-relevant system and DMN are incongruent with the previously suggested notion of anti-correlation of the two systems. The context-dependent correlation by psycho

  11. Age-Related Differences and Cognitive Correlates of Self-Reported and Direct Navigation Performance: The Effect of Real and Virtual Test Conditions Manipulation.

    PubMed

    Taillade, Mathieu; N'Kaoua, Bernard; Sauzéon, Hélène

    2015-01-01

    The present study investigated the effect of aging on direct navigation measures and self-reported ones according to the real-virtual test manipulation. Navigation (wayfinding tasks) and spatial memory (paper-pencil tasks) performances, obtained either in real-world or in virtual-laboratory test conditions, were compared between young (n = 32) and older (n = 32) adults who had self-rated their everyday navigation behavior (SBSOD scale). Real age-related differences were observed in navigation tasks as well as in paper-pencil tasks, which investigated spatial learning relative to the distinction between survey-route knowledge. The manipulation of test conditions (real vs. virtual) did not change these age-related differences, which are mostly explained by age-related decline in both spatial abilities and executive functioning (measured with neuropsychological tests). In contrast, elderly adults did not differ from young adults in their self-reporting relative to everyday navigation, suggesting some underestimation of navigation difficulties by elderly adults. Also, spatial abilities in young participants had a mediating effect on the relations between actual and self-reported navigation performance, but not for older participants. So, it is assumed that the older adults carried out the navigation task with fewer available spatial abilities compared to young adults, resulting in inaccurate self-estimates.

  12. Age-Related Differences and Cognitive Correlates of Self-Reported and Direct Navigation Performance: The Effect of Real and Virtual Test Conditions Manipulation

    PubMed Central

    Taillade, Mathieu; N'Kaoua, Bernard; Sauzéon, Hélène

    2016-01-01

    The present study investigated the effect of aging on direct navigation measures and self-reported ones according to the real-virtual test manipulation. Navigation (wayfinding tasks) and spatial memory (paper-pencil tasks) performances, obtained either in real-world or in virtual-laboratory test conditions, were compared between young (n = 32) and older (n = 32) adults who had self-rated their everyday navigation behavior (SBSOD scale). Real age-related differences were observed in navigation tasks as well as in paper-pencil tasks, which investigated spatial learning relative to the distinction between survey-route knowledge. The manipulation of test conditions (real vs. virtual) did not change these age-related differences, which are mostly explained by age-related decline in both spatial abilities and executive functioning (measured with neuropsychological tests). In contrast, elderly adults did not differ from young adults in their self-reporting relative to everyday navigation, suggesting some underestimation of navigation difficulties by elderly adults. Also, spatial abilities in young participants had a mediating effect on the relations between actual and self-reported navigation performance, but not for older participants. So, it is assumed that the older adults carried out the navigation task with fewer available spatial abilities compared to young adults, resulting in inaccurate self-estimates. PMID:26834666

  13. Age-related changes to spectral voice characteristics affect judgments of prosodic, segmental, and talker attributes for child and adult speech

    PubMed Central

    Dilley, Laura C.; Wieland, Elizabeth A.; Gamache, Jessica L.; McAuley, J. Devin; Redford, Melissa A.

    2013-01-01

    Purpose As children mature, changes in voice spectral characteristics covary with changes in speech, language, and behavior. Spectral characteristics were manipulated to alter the perceived ages of talkers’ voices while leaving critical acoustic-prosodic correlates intact, to determine whether perceived age differences were associated with differences in judgments of prosodic, segmental, and talker attributes. Method Speech was modified by lowering formants and fundamental frequency, for 5-year-old children’s utterances, or raising them, for adult caregivers’ utterances. Next, participants differing in awareness of the manipulation (Exp. 1a) or amount of speech-language training (Exp. 1b) made judgments of prosodic, segmental, and talker attributes. Exp. 2 investigated the effects of spectral modification on intelligibility. Finally, in Exp. 3 trained analysts used formal prosody coding to assess prosodic characteristics of spectrally-modified and unmodified speech. Results Differences in perceived age were associated with differences in ratings of speech rate, fluency, intelligibility, likeability, anxiety, cognitive impairment, and speech-language disorder/delay; effects of training and awareness of the manipulation on ratings were limited. There were no significant effects of the manipulation on intelligibility or formally coded prosody judgments. Conclusions Age-related voice characteristics can greatly affect judgments of speech and talker characteristics, raising cautionary notes for developmental research and clinical work. PMID:23275414

  14. The mechanical properties of ex vivo bovine and porcine crystalline lenses: age-related changes and location-dependent variations.

    PubMed

    Yoon, Sangpil; Aglyamov, Salavat; Karpiouk, Andrei; Emelianov, Stanislav

    2013-06-01

    The mechanical properties of ex vivo animal lenses from three groups were evaluated: old bovine (25-30 mo old, n = 4), young bovine (6 mo old, n = 4) and young porcine (6 mo old, n = 4) eye globes. We measured the dynamics of laser-induced microbubbles created at different locations within the crystalline lenses. An impulsive acoustic radiation force was applied to the microbubble, and the microbubble displacements were measured using a custom-built high pulse repetition frequency ultrasound system. Based on the measured dynamics of the microbubbles, Young's moduli of bovine and porcine lens tissue in the vicinity of the microbubbles were reconstructed. Age-related changes and location-dependent variations in the Young's modulus of the lenses were observed. Near the center, the old bovine lenses had a Young's modulus approximately fivefold higher than that of young bovine and porcine lenses. The gradient of Young's modulus with respect to radial distance was observed in the lenses from three groups.

  15. Age-related changes in phagocytic activity and production of pro-inflammatory cytokines by lipopolysaccharide stimulated porcine alveolar macrophages.

    PubMed

    Islam, Mohammad Ariful; Uddin, Muhammad Jasim; Tholen, Ernst; Tesfaye, Dawit; Looft, Christian; Schellander, Karl; Cinar, Mehmet Ulas

    2012-12-01

    The aim of the present study was to determine the age-related changes of phagocytic capacity and the kinetic production of cytokines in lipopolysaccharide-stimulated porcine alveolar macrophages. For this purpose, AMs were isolated from 5 (newborn), 40 (post-weaned) and 120 (young) day old pigs. Results of phagocytosis assay showed that AMs from newborn piglets had less phagocytic capacity than those of young pigs (P<0.05). For the kinetics study, cells and supernatant were collected at 1, 6, 12, 24, 36 and 48 h after LPS stimulation for quantification of cytokine mRNA and protein by quantitative real-time PCR and ELISA, respectively. The kinetics results showed that AMs from newborn piglets were significantly less capable of producing IL1β, IL6, IL12β, TNFα and IL8 than post-weaned piglets or young pigs. IL18 mRNA did not show significant differences between ages. MIP2 and MCP1 mRNA was higher in young pigs. Hence, higher production of cytokines by AMs may be the surfactant factors in the pulmonary host defense system. These results indicate that AMs from newborn piglets might be functionally immature, which may lead to increased susceptibility to lung infections. Future studies of cytokine kinetics in more animals are clearly needed to confirm these results across a wider age range.

  16. Age-related changes in serological susceptibility patterns to measles: results from a seroepidemiological study in Dongguan, China.

    PubMed

    Xiong, Yongzhen; Wang, Dong; Lin, Weiyan; Tang, Hao; Chen, Shaoli; Ni, Jindong

    2014-01-01

    The present study was performed to determine the seroprevalence of IgG measles antibodies in Dongguan residents (irrespective of vaccination status), to analyze the changes in age-related serological susceptibility patterns. A total of 1960 residents aged 0-60 years and 315 mother-infant pairs were studied. Serum IgG antibodies against measles virus were measured by ELISA. The overall seroprevalence was 93.4% in the general population in Dongguan, China. In subgroups aged 1-29 years who were likely vaccinated, there was a declining trend of seropositivity with age from 98.6% at 1-4 years to 85.7% at 20-29 years (P<0.0001). Seroprevalence were near or>95% in the older population (30-39 years and ≥ 40 years) who had not been immunized against measles. Age and sex were independent factors associated with seropositivity. Seroprevalence in pregnant women and their newborns was 87.0% and 84.1%, respectively. Our results suggest that the waning vaccine-induced immunity may be the main cause of increased serological susceptibility in young adults and young infants. An additional vaccination strategy that targets young adults is important for elimination of measles. PMID:24448194

  17. Aging-related anatomical and biochemical changes in lymphatic collectors impair lymph transport, fluid homeostasis, and pathogen clearance

    PubMed Central

    Zolla, Valerio; Nizamutdinova, Irina Tsoy; Scharf, Brian; Clement, Cristina C; Maejima, Daisuke; Akl, Tony; Nagai, Takashi; Luciani, Paola; Leroux, Jean-Christophe; Halin, Cornelia; Stukes, Sabriya; Tiwari, Sangeeta; Casadevall, Arturo; Jacobs, William R; Entenberg, David; Zawieja, David C; Condeelis, John; Fooksman, David R; Gashev, Anatoliy A; Santambrogio, Laura

    2015-01-01

    The role of lymphatic vessels is to transport fluid, soluble molecules, and immune cells to the draining lymph nodes. Here, we analyze how the aging process affects the functionality of the lymphatic collectors and the dynamics of lymph flow. Ultrastructural, biochemical, and proteomic analysis indicates a loss of matrix proteins, and smooth muscle cells in aged collectors resulting in a decrease in contraction frequency, systolic lymph flow velocity, and pumping activity, as measured in vivo in lymphatic collectors. Functionally, this impairment also translated into a reduced ability for in vivo bacterial transport as determined by time-lapse microscopy. Ultrastructural and proteomic analysis also indicates a decrease in the thickness of the endothelial cell glycocalyx and loss of gap junction proteins in aged lymph collectors. Redox proteomic analysis mapped an aging-related increase in the glycation and carboxylation of lymphatic’s endothelial cell and matrix proteins. Functionally, these modifications translate into apparent hyperpermeability of the lymphatics with pathogen escaping from the collectors into the surrounding tissue and a decreased ability to control tissue fluid homeostasis. Altogether, our data provide a mechanistic analysis of how the anatomical and biochemical changes, occurring in aged lymphatic vessels, compromise lymph flow, tissue fluid homeostasis, and pathogen transport. PMID:25982749

  18. Age-related changes in distribution of body weight on soles of feet for selected actions and postures.

    PubMed

    Yanagida, T; Asami, T

    1997-12-01

    We investigated age-related changes in the distribution of body weight on soles of feet in 878 healthy subjects ranging from 5 to 80 years of age. By modifying Morton's Staticometer, we constructed an instrument for measuring body-weight distribution over three areas of soles of the feet, the big toe (inner forefoot), the other four toes combined (outer forefoot) and the heels for both feet, thus a total of six areas. The weights in the six areas were recorded at the completion of nine selected actions and postures. We observed that for inhaling and exhaling standing postures, generally younger subjects had a ratio close to 1:2:3 for weights recorded for the inner toe:outer toes:heels as observed by Morton, but elderly subjects had a smaller value than 3 for the heel. The body-weight distribution tended to shift from heels to outer toes across age groups, which was more distinctly observed in women than in men.

  19. Age-related and depot-specific changes in white adipose tissue of growth hormone receptor-null mice.

    PubMed

    Sackmann-Sala, Lucila; Berryman, Darlene E; Lubbers, Ellen R; Zhang, Han; Vesel, Clare B; Troike, Katie M; Gosney, Elahu S; List, Edward O; Kopchick, John J

    2014-01-01

    Growth hormone receptor-null (GHR(-/-)) mice are dwarf, insulin sensitive, and long-lived in spite of increased adiposity. However, their adiposity is not uniform, with select white adipose tissue (WAT) depots enlarged. To study WAT depot-specific effects on insulin sensitivity and life span, we analyzed individual WAT depots of 12- and 24-month-old GHR(-) (/-) and wild-type (WT) mice, as well as their plasma levels of selected hormones. Adipocyte sizes and plasma insulin, leptin, and adiponectin levels decreased with age in both GHR(-) (/-) and WT mice. Two-dimensional gel electrophoresis proteomes of WAT depots were similar among groups, but several proteins involved in endocytosis and/or cytoskeletal organization (Ehd2, S100A10, actin), anticoagulation (S100A10, annexin A5), and age-related conditions (alpha2-macroglobulin, apolipoprotein A-I, transthyretin) showed significant differences between genotypes. Because Ehd2 may regulate endocytosis of Glut4, we measured Glut4 levels in the WAT depots of GHR(-) (/-) and WT mice. Inguinal WAT of 12-month-old GHR(-) (/-) mice displayed lower levels of Glut4 than WT. Overall, the protein changes detected in this study offer new insights into possible mechanisms contributing to enhanced insulin sensitivity and extended life span in GHR(-) (/-) mice. PMID:23873966

  20. Membrane lipid rafts and neurobiology: age-related changes in membrane lipids and loss of neuronal function.

    PubMed

    Egawa, Junji; Pearn, Matthew L; Lemkuil, Brian P; Patel, Piyush M; Head, Brian P

    2016-08-15

    A better understanding of the cellular physiological role that plasma membrane lipids, fatty acids and sterols play in various cellular systems may yield more insight into how cellular and whole organ function is altered during the ageing process. Membrane lipid rafts (MLRs) within the plasma membrane of most cells serve as key organizers of intracellular signalling and tethering points of cytoskeletal components. MLRs are plasmalemmal microdomains enriched in sphingolipids, cholesterol and scaffolding proteins; they serve as a platform for signal transduction, cytoskeletal organization and vesicular trafficking. Within MLRs are the scaffolding and cholesterol binding proteins named caveolin (Cav). Cavs not only organize a multitude of receptors including neurotransmitter receptors (NMDA and AMPA receptors), signalling proteins that regulate the production of cAMP (G protein-coupled receptors, adenylyl cyclases, phosphodiesterases (PDEs)), and receptor tyrosine kinases involved in growth (Trk), but also interact with components that modulate actin and tubulin cytoskeletal dynamics (e.g. RhoGTPases and actin binding proteins). MLRs are essential for the regulation of the physiology of organs such as the brain, and age-related loss of cholesterol from the plasma membrane leads to loss of MLRs, decreased presynaptic vesicle fusion, and changes in neurotransmitter release, all of which contribute to different forms of neurodegeneration. Thus, MLRs provide an active membrane domain that tethers and reorganizes the cytoskeletal machinery necessary for membrane and cellular repair, and genetic interventions that restore MLRs to normal cellular levels may be exploited as potential therapeutic means to reverse the ageing and neurodegenerative processes.

  1. Beat-induced fluctuations in auditory cortical beta-band activity: using EEG to measure age-related changes

    PubMed Central

    Cirelli, Laura K.; Bosnyak, Dan; Manning, Fiona C.; Spinelli, Christina; Marie, Céline; Fujioka, Takako; Ghahremani, Ayda; Trainor, Laurel J.

    2014-01-01

    People readily extract regularity in rhythmic auditory patterns, enabling prediction of the onset of the next beat. Recent magnetoencephalography (MEG) research suggests that such prediction is reflected by the entrainment of oscillatory networks in the brain to the tempo of the sequence. In particular, induced beta-band oscillatory activity from auditory cortex decreases after each beat onset and rebounds prior to the onset of the next beat across tempi in a predictive manner. The objective of the present study was to examine the development of such oscillatory activity by comparing electroencephalography (EEG) measures of beta-band fluctuations in 7-year-old children to adults. EEG was recorded while participants listened passively to isochronous tone sequences at three tempi (390, 585, and 780 ms for onset-to-onset interval). In adults, induced power in the high beta-band (20–25 Hz) decreased after each tone onset and rebounded prior to the onset of the next tone across tempo conditions, consistent with MEG findings. In children, a similar pattern was measured in the two slower tempo conditions, but was weaker in the fastest condition. The results indicate that the beta-band timing network works similarly in children, although there are age-related changes in consistency and the tempo range over which it operates. PMID:25071691

  2. Age-related changes in natural killer cell repertoires: impact on NK cell function and immune surveillance.

    PubMed

    Manser, Angela R; Uhrberg, Markus

    2016-04-01

    A key feature of human natural killer (NK) cells, which enables efficient recognition of infected and malignant target cells, is the expression of HLA class I-specific receptors of the KIR and NKG2 gene families. Cell-to-cell variability in receptor expression leads to the formation of complex NK cell repertoires. As outlined here, NK cells go through major changes from newborns to adults characterized by downregulation of the inhibitory NKG2A receptor and concomitant upregulation of KIR family members. This process is completed in young adults, and in the majority of individuals, KIR/NKG2A repertoires remain remarkably stable until old age. Nonetheless, age-related factors have the potential to majorly influence the complexity of NK cell repertoires: Firstly infection with HCMV is associated with major clonal expansions of terminally differentiated NKG2C- and KIR-expressing NK cells in certain individuals. Secondly, ineffective hematopoiesis can lead to immature and less diversified NK cell repertoires as observed in myelodysplastic syndrome (MDS), a malignant disease of the elderly. Thus, whereas in the majority of elderly the NK cell compartment appears to be highly stable in terms of function and phenotype, in a minority of subjects a breakdown of NK cell repertoire diversity is observed that might influence immune surveillance and healthy aging.

  3. Children’s Internal Attributions of Anxiety-Related Physical Symptoms: Age-Related Patterns and the Role of Cognitive Development and Anxiety Sensitivity

    PubMed Central

    Mayer, Birgit; Freher, Nancy Kramer; Duncan, Sylvana; van den Hout, Annemiek

    2010-01-01

    The present study examined age-related patterns in children’s anxiety-related interpretations and internal attributions of physical symptoms. A large sample of 388 children aged between 4 and 13 years completed a vignette paradigm during which they had to explain the emotional response of the main character who experienced anxiety-related physical symptoms in a variety of daily situations. In addition, children completed measures of cognitive development and anxiety sensitivity. Results demonstrated that age, cognitive development, and anxiety sensitivity were all positively related to children’s ability to perceive physical symptoms as a signal of anxiety and making internal attributions. Further, while a substantial proportion of the younger children (i.e., <7 years) were able to make a valid anxiety-related interpretation of a physical symptom, very few were capable of making an internal attribution, which means that children of this age lack the developmental prerequisites for applying physical symptoms-based theories of childhood anxiety. PMID:20440551

  4. Age-Related Changes in Dynamic Postural Control and Attentional Demands are Minimally Affected by Local Muscle Fatigue

    PubMed Central

    Remaud, Anthony; Thuong-Cong, Cécile; Bilodeau, Martin

    2016-01-01

    Normal aging results in alterations in the visual, vestibular and somtaosensory systems, which in turn modify the control of balance. Muscle fatigue may exacerbate these age-related changes in sensory and motor functions, and also increase the attentional demands associated with dynamic postural control. The purpose of this study was to investigate the effect of aging on dynamic postural control and posture-related attentional demands before and after a plantar flexor fatigue protocol. Participants (young adults: n = 15; healthy seniors: n = 13) performed a dynamic postural task along the antero-posterior (AP) and the medio-lateral (ML) axes, with and without the addition of a simple reaction time (RT) task. The dynamic postural task consisted in following a moving circle on a computer screen with the representation of the center of pressure (COP). This protocol was repeated before and after a fatigue task where ankle plantar flexor muscles were targeted. The mean COP-target distance and the mean COP velocity were calculated for each trial. Cross-correlation analyses between the COP and target displacements were also performed. RTs were recorded during dual-task trials. Results showed that while young adults adopted an anticipatory control mode to move their COP as close as possible to the target center, seniors adopted a reactive control mode, lagging behind the target center. This resulted in longer COP-target distance and higher COP velocity in the latter group. Concurrently, RT increased more in seniors when switching from static stance to dynamic postural conditions, suggesting potential alterations in the central nervous system (CNS) functions. Finally, plantar flexor muscle fatigue and dual-tasking had only minor effects on dynamic postural control of both young adults and seniors. Future studies should investigate why the fatigue-induced changes in quiet standing postural control do not seem to transfer to dynamic balance tasks. PMID:26834626

  5. Age-related changes in the rate of disease transmission: implications for the design of vaccination programmes.

    PubMed Central

    Anderson, R. M.; May, R. M.

    1985-01-01

    Mathematical models are developed to aid in the investigation of the implications of heterogeneity in contact with infection within a community, on the design of mass vaccination programmes for the control of childhood viral and bacterial infections in developed countries. Analyses are focused on age-dependency in the rate at which individuals acquire infection, the question of 'who acquires infection from whom', and the implications of genetic variability in susceptibility to infection. Throughout, theoretical predictions are based on parameter estimates obtained from epidemiological studies and are compared with observed temporal trends in disease incidence and age-stratified serological profiles. Analysis of case notification records and serological data suggest that the rate at which individuals acquire many common infections changes from medium to high and then to low levels in the infant, child and teenage plus adult age groups respectively. Such apparent age-dependency in attack rate acts to reduce slightly the predicted levels of herd immunity required for the eradication of infections such as measles, when compared with the predictions of models based on age-independent transmission. The action of maternally derived immunity in prohibiting vaccination in infants, and the broad span of age classes over which vaccination currently takes place in the U.K., however, argue that levels of herd immunity of between 90 and 94% would be required to eliminate measles. Problems surrounding the interpretation of apparent age-related trends in the acquisition of infection and their relevance to the design of vaccination programmes, are discussed in relation to the possible role of genetically based variation in susceptibility to infection and observations on epidemics in 'virgin' populations. Heterogeneous mixing models provide predictions of changes in serology and disease incidence under the impact of mass vaccination which well mirror observed trends in England and

  6. Age-Related Changes of Intraocular Pressure in Elderly People in Southern China: Lingtou Eye Cohort Study

    PubMed Central

    Han, Xiaotong; Niu, Yong; Guo, Xinxing; Hu, Yin; Yan, William; He, Mingguang

    2016-01-01

    Purpose To study age-related changes of intraocular pressure (IOP) and assess the cohort effect in both cross-sectional and longitudinal settings among elderly Chinese adults. Methods Participants were enrolled from the Lingtou Eye Cohort Study with Chinese government officials aged 40 years and older at baseline and received physical check-up and ocular examinations from 2010 to 2012. IOP was measured using a non-contact tonometer according to standardized protocols, as well as systolic blood pressure (SBP), diastolic blood pressure (DBP) and body mass index (BMI). Participants who had attended IOP measurements in both 2010 and 2012 were included in this study. Cross-sectional association of IOP with age was assessed using multivariate liner regression analyses and based on the data of 2010. Longitudinal changes in IOP were assessed by paired t-test. Results A total of 3372 subjects were enrolled in the current analysis (2010 mean [SD] age, 61.9 [7.1] years; 60.2% men). The mean IOP in 2010 was 15.4±2.3 mmHg for women and 15.2±2.3 mmHg for men with an intersex difference (P = 0.029). Cross-sectional analysis showed that IOP was negatively associated with age (P = 0.003, β = -0.033 for women and P<0.001, β = -0.061 for men) adjusted for baseline SBP, DBP and BMI. Paired t-test suggested that IOP was higher in the year 2012 than 2010 in women (P = 0.006) but did not change significantly in men within 2 years (P = 0.345). In addition, the 2-year changes of IOP were not associated with age adjusted for baseline IOP in 2010 (P = 0.249). Conclusion Cross-sectional data suggests that IOP is lower in people with older age. Longitudinal data does not support such findings and thus the identified decreasing pattern with age in cross-sectional analysis is likely caused by cohort effects. PMID:26986222

  7. Automated Retinal Image Analysis for Evaluation of Focal Hyperpigmentary Changes in Intermediate Age-Related Macular Degeneration

    PubMed Central

    Schmitz-Valckenberg, Steffen; Göbel, Arno P.; Saur, Stefan C.; Steinberg, Julia S.; Thiele, Sarah; Wojek, Christian; Russmann, Christoph; Holz, Frank G.; for the MODIAMD-Study Group

    2016-01-01

    Purpose To develop and evaluate a software tool for automated detection of focal hyperpigmentary changes (FHC) in eyes with intermediate age-related macular degeneration (AMD). Methods Color fundus (CFP) and autofluorescence (AF) photographs of 33 eyes with FHC of 28 AMD patients (mean age 71 years) from the prospective longitudinal natural history MODIAMD-study were included. Fully automated to semiautomated registration of baseline to corresponding follow-up images was evaluated. Following the manual circumscription of individual FHC (four different readings by two readers), a machine-learning algorithm was evaluated for automatic FHC detection. Results The overall pixel distance error for the semiautomated (CFP follow-up to CFP baseline: median 5.7; CFP to AF images from the same visit: median 6.5) was larger as compared for the automated image registration (4.5 and 5.7; P < 0.001 and P < 0.001). The total number of manually circumscribed objects and the corresponding total size varied between 637 to 1163 and 520,848 pixels to 924,860 pixels, respectively. Performance of the learning algorithms showed a sensitivity of 96% at a specificity level of 98% using information from both CFP and AF images and defining small areas of FHC (“speckle appearance”) as “neutral.” Conclusions FHC as a high-risk feature for progression of AMD to late stages can be automatically assessed at different time points with similar sensitivity and specificity as compared to manual outlining. Upon further development of the research prototype, this approach may be useful both in natural history and interventional large-scale studies for a more refined classification and risk assessment of eyes with intermediate AMD. Translational Relevance Automated FHC detection opens the door for a more refined and detailed classification and risk assessment of eyes with intermediate AMD in both natural history and future interventional studies. PMID:26966639

  8. Visceral adipose tissue inflammation is associated with age-related brain changes and ischemic brain damage in aged mice.

    PubMed

    Shin, Jin A; Jeong, Sae Im; Kim, Minsuk; Yoon, Joo Chun; Kim, Hee-Sun; Park, Eun-Mi

    2015-11-01

    Visceral adipose tissue is accumulated with aging. An increase in visceral fat accompanied by low-grade inflammation is associated with several adult-onset diseases. However, the effects of visceral adipose tissue inflammation on the normal and ischemic brains of aged are not clearly defined. To examine the role of visceral adipose tissue inflammation, we evaluated inflammatory cytokines in the serum, visceral adipose tissue, and brain as well as blood-brain barrier (BBB) permeability in aged male mice (20 months) underwent sham or visceral fat removal surgery compared with the young mice (2.5 months). Additionally, ischemic brain injury was compared in young and aged mice with sham and visceral fat removal surgery. Interleukin (IL)-1β, IL-6, and tumor necrosis factor-α levels in examined organs were increased in aged mice compared with the young mice, and these levels were reduced in the mice with visceral fat removal. Increased BBB permeability with reduced expression of tight junction proteins in aged sham mice were also decreased in mice with visceral fat removal. After focal ischemic injury, aged mice with visceral fat removal showed a reduction in infarct volumes, BBB permeability, and levels of proinflammatory cytokines in the ischemic brain compared with sham mice, although the neurological outcomes were not significantly improved. In addition, further upregulated visceral adipose tissue inflammation in response to ischemic brain injury was attenuated in mice with visceral fat removal. These results suggest that visceral adipose tissue inflammation is associated with age-related changes in the brain and contributes to the ischemic brain damage in the aged mice. We suggest that visceral adiposity should be considered as a factor affecting brain health and ischemic brain damage in the aged population.

  9. Membrane lipid rafts and neurobiology: age-related changes in membrane lipids and loss of neuronal function.

    PubMed

    Egawa, Junji; Pearn, Matthew L; Lemkuil, Brian P; Patel, Piyush M; Head, Brian P

    2016-08-15

    A better understanding of the cellular physiological role that plasma membrane lipids, fatty acids and sterols play in various cellular systems may yield more insight into how cellular and whole organ function is altered during the ageing process. Membrane lipid rafts (MLRs) within the plasma membrane of most cells serve as key organizers of intracellular signalling and tethering points of cytoskeletal components. MLRs are plasmalemmal microdomains enriched in sphingolipids, cholesterol and scaffolding proteins; they serve as a platform for signal transduction, cytoskeletal organization and vesicular trafficking. Within MLRs are the scaffolding and cholesterol binding proteins named caveolin (Cav). Cavs not only organize a multitude of receptors including neurotransmitter receptors (NMDA and AMPA receptors), signalling proteins that regulate the production of cAMP (G protein-coupled receptors, adenylyl cyclases, phosphodiesterases (PDEs)), and receptor tyrosine kinases involved in growth (Trk), but also interact with components that modulate actin and tubulin cytoskeletal dynamics (e.g. RhoGTPases and actin binding proteins). MLRs are essential for the regulation of the physiology of organs such as the brain, and age-related loss of cholesterol from the plasma membrane leads to loss of MLRs, decreased presynaptic vesicle fusion, and changes in neurotransmitter release, all of which contribute to different forms of neurodegeneration. Thus, MLRs provide an active membrane domain that tethers and reorganizes the cytoskeletal machinery necessary for membrane and cellular repair, and genetic interventions that restore MLRs to normal cellular levels may be exploited as potential therapeutic means to reverse the ageing and neurodegenerative processes. PMID:26332795

  10. Age-related changes in glucose utilization and fatty acid oxidation in a muscle-specific manner during rabbit growth.

    PubMed

    Gondret, Florence; Damon, Marie; Jadhao, Sanjay B; Houdebine, Louis-Marie; Herpin, Patrick; Hocquette, Jean-François

    2004-01-01

    The optimal utilization of energy substrates in muscle fibers is of primary importance for muscle contraction and whole body physiology. This study aimed to investigate the age-related changes in some indicators of glucose catabolism and fatty acid oxidation in muscles of growing rabbits. Longissimus lumborum (fast-twitch, LL) and semimembranosus proprius (slow-twitch, SMP) muscles were collected at 10 or 20 weeks of age ( n=6 per age). Glucose transporter GLUT4 content was investigated by immunoblot assay. Activity levels of five enzymes were measured: lactate dehydrogenase (LDH) and phosphofructokinase (PFK) for glycolysis; citrate synthase (CS), isocitrate dehydrogenase (ICDH) and -3-hydroxyacyl-coenzyme A dehydrogenase (HAD) for oxidation. Mitochondrial and peroxisomal oxidation rates were assessed on fresh homogenates using [1-14C]-oleate as substrate. At both ages, mitochondrial and peroxisomal oxidations rates, as well as activities of oxidative enzymes were higher in SMP than in LL. In both muscles, the apparent rate of fatty acid oxidation by the mitochondria did not differ between the two ages. However, a decrease in the activities of the three oxidative enzymes was observed in LL, whereas activities of CS and HAD and peroxisomal oxidation rate of oleate increased between the two ages in SMP muscle. In both muscles, LDH activity increased between 10 and 20 weeks, without variations in glucose uptake (GLUT4 transporter content) and in the first step of glucose utilization (PFK activity). In conclusion, mitochondrial oxidation rate of fatty acids and activities of selected mitochondrial enzymes were largely unrelated. Moreover, regulation of energy metabolism with advancing age differed between muscle types.

  11. SATB2-Nanog axis links age-related intrinsic changes of mesenchymal stem cells from craniofacial bone

    PubMed Central

    Xu, Rongyao; Ge, Jie; Fu, Yu; Zhang, Yuchao; Du, Yifei; Ye, Jinhai; Cheng, Jie; Jiang, Hongbing

    2016-01-01

    Bone mesenchymal stem cells (BMSCs) senescence contributes to age-related bone loss. The alveolar bone in jaws originates from neural crest cells and possesses significant site- and age-related properties. However, such intrinsic characteristics of BMSCs from alveolar bone (AB-BMSCs) and the underlying regulatory mechanisms still remain unknown. Here, we found that the expression of special AT-rich binding protein 2 (SATB2) in human AB-BMSCs significantly decreased with aging. SATB2 knockdown on AB-BMSCs from young donors displayed these aging-related phenotypes in vitro. Meanwhile, enforced SATB2 overexpression could rejuvenate AB-BMSCs from older donors. Importantly, satb2 gene- modified BMSCs therapy could prevent the alveolar bone loss during the aging of rats. Mechanistically, the stemness regulator Nanog was identified as the direct transcriptional target of SATB2 in BMSCs and functioned as a downstream mediator of SATB2. Collectively, our data reveal that SATB2 in AB-BMSCs associates with their age-related properties, and prevents AB-BMSCs senescence via maintaining Nanog expression. These findings highlight the translational potential of transcriptional factor-based cellular reprogramming for anti-aging therapy. PMID:27632702

  12. Treadmill exercise induces age-related changes in aversive memory, neuroinflammatory and epigenetic processes in the rat hippocampus.

    PubMed

    Lovatel, Gisele Agustini; Elsner, Viviane Rostirola; Bertoldi, Karine; Vanzella, Cláudia; Moysés, Felipe Dos Santos; Vizuete, Adriana; Spindler, Christiano; Cechinel, Laura Reck; Netto, Carlos Alexandre; Muotri, Alysson Renato; Siqueira, Ionara Rodrigues

    2013-03-01

    It has been described that exercise can modulate both inflammatory response and epigenetic modifications, although the effect of exercise on these parameters during the normal brain aging process yet remains poorly understood. Here, we investigated the effect of aging and treadmill exercise on inflammatory and epigenetic parameters specifically pro and anti-inflammatory cytokines levels, activation of NF-kB and histone H4 acetylation levels in hippocampus from Wistar rats. Additionally, we evaluated aversive memory through inhibitory avoidance task. Rats of 3 and 20 months of age were assigned to non-exercised (sedentary) and exercised (running daily for 20 min for 2 weeks) groups. The effect of daily forced exercise in the treadmill was assessed. The levels of inflammatory and epigenetic parameters were determined 1h, 18 h, 3 days or 7 days after the last training session of exercise. It was observed an age-related decline on aversive memory, as well as aged rats showed increased hippocampal levels of inflammatory markers, such as TNFα, IL1-β and NF-kB and decreased IL-4 levels, an anti-inflammatory cytokine. Moreover, lower levels of global histone H4 acetylation were also observed in hippocampi from aged rats. Interestingly, there was a significant correlation between the biochemical markers and the inhibitory avoidance test performance. The forced exercise protocol ameliorated aging-related memory decline, decreased pro-inflammatory markers and increased histone H4 acetylation levels in hippocampi 20-months-old rats, while increased acutely IL-4 levels in hippocampi from young adult rats. Together, these results suggest that an imbalance of inflammatory markers might be involved to the aging-related aversive memory impairment. Additionally, our exercise protocol may reverse aging-related memory decline through improving cytokine profile.

  13. Glutamatergic treatment strategies for age-related memory disorders.

    PubMed

    Müller, W E; Scheuer, K; Stoll, S

    1994-01-01

    Age-related changes of N-methyl-D-aspartate (NMDA) receptors have been found in cortical areas and in the hippocampus of many species. On the basis of a variety of experimental observations it has been suggested that the decrease of NMDA receptor density might be one of the causative factors of the cognitive decline with aging. Based on these findings several strategies have been developed to improve cognition by compensating the NMDA receptor deficits in aging. The most promising approaches are the indirect activation of glutamatergic neurotransmission by agonists of the glycine site or the restoration of the age-related deficit of receptor density by several nootropics. PMID:7997073

  14. Age-Related Change of the Mean Level and Intraindividual Variability of Saccadic Reaction Time Performance in Persons with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Haishi, Koichi; Okuzumi, Hideyuki; Kokubun, Mitsuru

    2013-01-01

    The current study examined age-related change of saccadic reaction time (SRT) in persons with intellectual disabilities (ID). Participants were 29 persons with intellectual disabilities aged between 14 and 34 years whose IQs were between 14 and 70. Participants were divided into Group I (IQ greater than or equal to 35) and Group II (IQ less than…

  15. A Prospective Longitudinal Study of Shyness from Infancy to Adolescence: Stability, Age-Related Changes, and Prediction of Socio-Emotional Functioning

    ERIC Educational Resources Information Center

    Karevold, Evalill; Ystrom, Eivind; Coplan, Robert J.; Sanson, Ann V.; Mathiesen, Kristin S.

    2012-01-01

    This longitudinal, population-based and prospective study investigated the stability, age-related changes, and socio-emotional outcomes of shyness from infancy to early adolescence. A sample of 921 children was followed from ages 1.5 to 12.5 years. Parent-reported shyness was assessed at five time points and maternal- and self-reported social…

  16. [Presbycusis - Age Related Hearing Loss].

    PubMed

    Fischer, N; Weber, B; Riechelmann, H

    2016-07-01

    Presbycusis or age related hearing loss can be defined as a progressive, bilateral and symmetrical sensorineural hearing loss due to age related degeneration of inner ear structures. It can be considered a multifactorial complex disorder with environmental and genetic factors. The molecular, electrophysiological and histological damage at different levels of the inner ear cause a progressive hearing loss, which usually affects the high frequencies of hearing. The resulting poor speech recognition has a negative impact on cognitive, emotional and social function in older adults. Recent investigations revealed an association between hearing impairment and social isolation, anxiety, depression and cognitive decline in elderly. These findings emphasize the importance of diagnosis and treating hearing loss in the elderly population. Hearing aids are the most commonly used devices for treating presbycusis. The technical progress of implantable hearing devices allows an effective hearing rehabilitation even in elderly with severe hearing loss. However, most people with hearing impairments are not treated adequately. PMID:27392191

  17. Future Global Change and Cognition.

    PubMed

    Lewandowsky, Stephan

    2016-01-01

    The 11 articles in this issue explore how people respond to climate change and other global challenges. The articles pursue three broad strands of enquiry that relate (1) to the effects and causes of "skepticism" about climate change, (2) the purely cognitive challenges that are posed by a complex scientific issue, and (3) the ways in which climate change can be communicated to a wider audience. Cognitive science can contribute to understanding people's responses to global challenges in many ways, and it may also contribute to implementing solutions to those problems. PMID:26749304

  18. Future Global Change and Cognition.

    PubMed

    Lewandowsky, Stephan

    2016-01-01

    The 11 articles in this issue explore how people respond to climate change and other global challenges. The articles pursue three broad strands of enquiry that relate (1) to the effects and causes of "skepticism" about climate change, (2) the purely cognitive challenges that are posed by a complex scientific issue, and (3) the ways in which climate change can be communicated to a wider audience. Cognitive science can contribute to understanding people's responses to global challenges in many ways, and it may also contribute to implementing solutions to those problems.

  19. Age related changes in pancreatic beta cells: A putative extra-cerebral site of Alzheimer’s pathology

    PubMed Central

    Maj, Magdalena; Ilhan, Aysegul; Neziri, Dashurie; Gartner, Wolfgang; Berggard, Tord; Attems, Johannes; Base, Wolfgang; Wagner, Ludwig

    2011-01-01

    Frequent concomitant manifestation of type 2 diabetes mellitus (T2DM) and Alzheimer’s disease (AD) has been recently demonstrated by epidemiological studies. This might be due to functional similarities between β-cells and neurons, such as secretion on demand of highly specific molecules in a tightly controlled fashion. An additional similarity represents the age-related alteration of hyperphosphorylated tau in AD patients. Similarly, alterations have been identified in β-cells of T2DM patients. The islet amyloid polypeptide has been associated with β-cell apoptosis. As a consequence of increasing age, the accumulation of highly modified proteins together with decreased regenerative potential might lead to increasing rates of apoptosis. Moreover, reduction of β-cell replication capabilities results in reduction of β-cell mass in mammals, simultaneously with impaired glucose tolerance. The new challenge is to learn much more about age-related protein modifications. This can lead to new treatment strategies for reducing the incidence of T2DM and AD. PMID:21537460

  20. A review of the equine age-related changes in the immune system: comparisons between human and equine aging, with focus on lung-specific immune-aging.

    PubMed

    Hansen, S; Baptiste, K E; Fjeldborg, J; Horohov, D W

    2015-03-01

    The equine aging process involves many changes to the immune system that may be related to genetics, the level of nutrition, the environment and/or an underlying subclinical disease. Geriatric horses defined as horses above the age of 20, exhibit a decline in body condition, muscle tone and general well-being. It is not known whether these changes contribute to decreased immune function or are the result of declining immune function. Geriatric years are characterized by increased susceptibility to infections and a reduced antibody response to vaccination as a result of changes in the immune system. Humans and horses share many of these age-related changes, with only a few differences. Thus, inflamm-aging and immunosenescence are well-described phenomena in both human and equine research, particularly in relation to the peripheral blood and especially the T-cell compartment. However, the lung is faced with unique challenges because of its constant interaction with the external environment and thus may not share similarities to peripheral blood when considering age-related changes in immune function. Indeed, recent studies have shown discrepancies in cytokine mRNA and protein expression between the peripheral blood and bronchoalveolar lavage immune cells. These results provide important evidence that age-related immune changes or 'dys-functions' are organ-specific.

  1. Cytogenetic study of some tissues and age-related changes in cell proportions in a goat-sheep chimera.

    PubMed

    Jaszczak, K; Parada, R; Guszkiewicz, A

    1999-01-01

    Different percentages of cells with a female sheep or male goat karyotype were found in kidney (12.0% vs. 88.0%) and lung (42.6% vs. 57.4%) cell cultures from a 10-year-old chimera. Skin biopsies from patches with goat hair or sheep wool showed different, age-related goat-to-sheep fibroblast ratios. Karyotypic analysis of lymphocytes obtained from peripheral blood of the chimera at 6 and 10 yr of age showed no chimerism. Two weeks after birth, however, lymphocytes with both sheep (54,XX) and goat (60,XY) karyotypes were apparent in the blood of this chimera. Twenty percent of the blood cells examined at 2 wk had a caprine karyotype; this proportion declined with time, until it was totally eliminated at age 6. PMID:10343103

  2. Low levels of aluminum can lead to behavioral and morphological changes associated with Alzheimer's disease and age-related neurodegeneration.

    PubMed

    Bondy, Stephen C

    2016-01-01

    Aluminum (Al) is a very common component of the earth's mineral composition. It is not essential element for life and is a constituent of rather inert minerals. Therefore, it has often been regarded as not presenting a significant health hazard. As a result, aluminum-containing agents been used in the preparation of many foodstuffs processing steps and also in elimination of particulate organic matter from water. More recently, the reduced pH of bodies of water resulting from acid rain has led to mobilization of aluminum-containing minerals into a more soluble form, and these have thus entered residential drinking water resources. By this means, the body burden of aluminum in humans has increased. Epidemiological and experimental findings indicate that aluminum is not as harmless as was previously thought, and that aluminum may contribute to the inception and advancement of Alzheimer's disease. Epidemiological data is reinforced by indications that aluminum exposure can result in excess inflammatory activity within the brain. Activation of the immune system not initiated by an infectious agent, typifies the aging brain and is even more augmented in several neurodegenerative diseases. The origin of most age-related neurological disorders is generally not known but as they are largely not of genetic derivation, their development is likely triggered by unknown environmental factors. There is a growing and consistent body of evidence that points to aluminum as being one such significant influence. Evidence is presented that reinforces the likelihood that aluminum is a factor speeding the rate of brain aging. Such acceleration would inevitably enlarge the incidence of age-related neurological diseases.

  3. Low levels of aluminum can lead to behavioral and morphological changes associated with Alzheimer's disease and age-related neurodegeneration.

    PubMed

    Bondy, Stephen C

    2016-01-01

    Aluminum (Al) is a very common component of the earth's mineral composition. It is not essential element for life and is a constituent of rather inert minerals. Therefore, it has often been regarded as not presenting a significant health hazard. As a result, aluminum-containing agents been used in the preparation of many foodstuffs processing steps and also in elimination of particulate organic matter from water. More recently, the reduced pH of bodies of water resulting from acid rain has led to mobilization of aluminum-containing minerals into a more soluble form, and these have thus entered residential drinking water resources. By this means, the body burden of aluminum in humans has increased. Epidemiological and experimental findings indicate that aluminum is not as harmless as was previously thought, and that aluminum may contribute to the inception and advancement of Alzheimer's disease. Epidemiological data is reinforced by indications that aluminum exposure can result in excess inflammatory activity within the brain. Activation of the immune system not initiated by an infectious agent, typifies the aging brain and is even more augmented in several neurodegenerative diseases. The origin of most age-related neurological disorders is generally not known but as they are largely not of genetic derivation, their development is likely triggered by unknown environmental factors. There is a growing and consistent body of evidence that points to aluminum as being one such significant influence. Evidence is presented that reinforces the likelihood that aluminum is a factor speeding the rate of brain aging. Such acceleration would inevitably enlarge the incidence of age-related neurological diseases. PMID:26687397

  4. The Canine Sand Maze: An Appetitive Spatial Memory Paradigm Sensitive to Age-Related Change in Dogs

    ERIC Educational Resources Information Center

    Salvin, Hannah E.; McGreevy, Paul D.; Sachdev, Perminder S.; Valenzuela, Michael J.

    2011-01-01

    Aged dogs exhibit a spectrum of cognitive abilities including a syndrome similar to Alzheimer's disease. A major impediment to research so far has been the lack of a quick and accurate test of visuospatial memory appropriate for community-based animals. We therefore report on the development and validation of the Canine Sand Maze. A 4.5-m-diameter…

  5. Age-related changes in skin blood flow at four anatomic sites of the body in males studied by xenon-133

    SciTech Connect

    Tsuchida, Y.

    1990-04-01

    The normal skin blood flow in healthy subjects consisting of 28 males whose ages ranged from 20 to 72 years was measured by the xenon-133 clearance method at four different sites of the body to determine the presence of any age-related changes. The following results were obtained: Significant age-related changes were observed in the skin blood flow of the deltoid region, anterior chest, dorsum of the hand, and dorsum of the foot. Normal skin blood flow was demonstrated to be highly dependent on age and to significantly decrease with age. Average skin blood flow at these four regions of those 70 years of age decreased by 30 to 40 percent when compared to that of those 20 years of age. The skin blood flow at the deltoid region of healthy subjects was higher by 6.3 ml/100 gm per minute than that of patients in poor condition with cancer of the head and neck.

  6. Possible Mechanisms Underlying Aging-Related Changes in Early Diastolic Filling and Long Axis Motion—Left Ventricular Length and Blood Pressure

    PubMed Central

    Peverill, Roger E.; Chou, Bon; Donelan, Lesley; Mottram, Philip M.; Gelman, John S.

    2016-01-01

    Background The transmitral E wave and the peak velocity of early diastolic mitral annular motion (e`) both decrease with age, but the mechanisms underlying these age-related changes are incompletely understood. This study investigated the possible contributions of blood pressure (BP) and left ventricular end-diastolic length (LVEDL) to age-related reductions in E and e`. Methods The study group were 82 healthy adult subjects <55 years of age who were not obese or hypertensive. Transmitral flow and mitral annular motion were recorded using pulsed-wave Doppler. LVEDL was measured from the mitral annular plane to the apical endocardium. Results Age was positively correlated with diastolic BP and septal wall thickness (SWT), inversely correlated with LVEDL (β = -0.25) after adjustment for sex and body surface area, but was not related to left ventricular end-diastolic diameter (LVEDD). Age was also inversely correlated with E (r = -0.36), septal e`(r = -0.53) and lateral e`(r = -0.53). On multivariable analysis, E was inversely correlated with diastolic BP and LVEDD, septal e`was inversely correlated with diastolic BP and positively correlated with SWT and LVEDL, after adjusting for body mass index, whilst lateral e`was inversely correlated with diastolic BP and positively correlated with LVEDL. Conclusion The above findings are consistent with higher BP being a contributor to age-related reductions in both E and e`and shortening of LVEDL with age being a contributor to the age-related reduction in e`. An implication of these findings is that slowing of myocyte relaxation is unlikely to be the sole, and may not be the main, mechanism underlying age-related decreases in E and e`. PMID:27351745

  7. Neural correlates of the age-related changes in motor sequence learning and motor adaptation in older adults.

    PubMed

    King, Bradley R; Fogel, Stuart M; Albouy, Geneviève; Doyon, Julien

    2013-01-01

    As the world's population ages, a deeper understanding of the relationship between aging and motor learning will become increasingly relevant in basic research and applied settings. In this context, this review aims to address the effects of age on motor sequence learning (MSL) and motor adaptation (MA) with respect to behavioral, neurological, and neuroimaging findings. Previous behavioral research investigating the influence of aging on motor learning has consistently reported the following results. First, the initial acquisition of motor sequences is not altered, except under conditions of increased task complexity. Second, older adults demonstrate deficits in motor sequence memory consolidation. And, third, although older adults demonstrate deficits during the exposure phase of MA paradigms, the aftereffects following removal of the sensorimotor perturbation are similar to young adults, suggesting that the adaptive ability of older adults is relatively intact. This paper will review the potential neural underpinnings of these behavioral results, with a particular emphasis on the influence of age-related dysfunctions in the cortico-striatal system on motor learning.

  8. Age-related changes in prosodic features of maternal speech to prelingually deaf infants with cochlear implants

    PubMed Central

    Kondaurova, Maria V.; Bergeson, Tonya R.; Xu, Huipuing

    2012-01-01

    This study investigated prosodic and structural characteristics of infant-directed speech to hearing-impaired infants as they gain hearing experience with a cochlear implant over a 12-month period of time. Mothers were recorded during a play interaction with their HI infants (N = 27, mean age 18.4 months) at 3, 6, and 12 months post-implantation. Two separate control groups of mothers with age-matched normal-hearing infants (NH-AM) (N = 21, mean age 18.1 months) and hearing experience-matched normal-hearing infants (NH-EM) (N = 24, mean age 3.1 months) were recorded at three testing sessions. Mothers produced less exaggerated pitch characteristics, a larger number of syllables per utterance, and faster speaking rate when interacting with NH-AM as compared to HI infants. Mothers also produced more syllables and demonstrated a trend suggesting faster speaking rate in speech to NH-EM relative to HI infants. Age-related modifications included decreased pitch standard deviation and increased number of syllables in speech to NH-AM infants and increased number of syllables in speech to HI and NH-EM infants across the 12-month period. These results suggest that mothers are sensitive to the hearing status of their infants and modify characteristics of infant-direct speech over time. PMID:24244108

  9. Glycolytic fast-twitch muscle fiber restoration counters adverse age-related changes in body composition and metabolism.

    PubMed

    Akasaki, Yuichi; Ouchi, Noriyuki; Izumiya, Yasuhiro; Bernardo, Barbara L; Lebrasseur, Nathan K; Walsh, Kenneth

    2014-02-01

    Aging is associated with the development of insulin resistance, increased adiposity, and accumulation of ectopic lipid deposits in tissues and organs. Starting in mid-life there is a progressive decline in lean muscle mass associated with the preferential loss of glycolytic, fast-twitch myofibers. However, it is not known to what extent muscle loss and metabolic dysfunction are causally related or whether they are independent epiphenomena of the aging process. Here, we utilized a skeletal-muscle-specific, conditional transgenic mouse expressing a constitutively active form of Akt1 to examine the consequences of glycolytic, fast-twitch muscle growth in young vs. middle-aged animals fed standard low-fat chow diets. Activation of the Akt1 transgene led to selective skeletal muscle hypertrophy, reversing the loss of lean muscle mass observed upon aging. The Akt1-mediated increase in muscle mass led to reductions in fat mass and hepatic steatosis in older animals, and corrected age-associated impairments in glucose metabolism. These results indicate that the loss of lean muscle mass is a significant contributor to the development of age-related metabolic dysfunction and that interventions that preserve or restore fast/glycolytic muscle may delay the onset of metabolic disease.

  10. Age-related profiling of DNA methylation in CD8+ T cells reveals changes in immune response and transcriptional regulator genes.

    PubMed

    Tserel, Liina; Kolde, Raivo; Limbach, Maia; Tretyakov, Konstantin; Kasela, Silva; Kisand, Kai; Saare, Mario; Vilo, Jaak; Metspalu, Andres; Milani, Lili; Peterson, Pärt

    2015-01-01

    Human ageing affects the immune system resulting in an overall decline in immunocompetence. Although all immune cells are affected during aging, the functional capacity of T cells is most influenced and is linked to decreased responsiveness to infections and impaired differentiation. We studied age-related changes in DNA methylation and gene expression in CD4+ and CD8+ T cells from younger and older individuals. We observed marked difference between T cell subsets, with increased number of methylation changes and higher methylome variation in CD8+ T cells with age. The majority of age-related hypermethylated sites were located at CpG islands of silent genes and enriched for repressive histone marks. Specifically, in CD8+ T cell subset we identified strong inverse correlation between methylation and expression levels in genes associated with T cell mediated immune response (LGALS1, IFNG, CCL5, GZMH, CCR7, CD27 and CD248) and differentiation (SATB1, TCF7, BCL11B and RUNX3). Our results thus suggest the link between age-related epigenetic changes and impaired T cell function. PMID:26286994

  11. Age-Related Changes in the Cardiometabolic Profiles in Singapore Resident Adult Population: Findings from the National Health Survey 2010

    PubMed Central

    Loh, Tze Ping; Ma, Stefan; Heng, Derrick; Khoo, Chin Meng

    2016-01-01

    We describe the centile trends of the blood pressure, glycemia and lipid profiles as well as renal function of a representative population who participated in the Singapore National Health Survey in 2010. Representative survey population was sampled in two phases, first using geographical/ residential dwelling type stratification, followed up ethnicity. 2,407 survey participants without any self-reported medical or medication history for diabetes mellitus, hypertension and dyslipidemia were included in this analysis. All biochemistry analyses were performed on Roche platforms. After excluding outliers using Tukey's criteria, the results of the remaining participants were subjected to lambda-mu-sigma (LMS) analysis. In men, systolic blood pressure increased linearly with age. By contrast, an upward inflection around late 40s was seen in women. The diastolic blood pressure was highest in men in the late 30s-50s age group, and in women in the late 50s-60s age group. All glycemia-related parameters, i.e. fasting and 2-hour plasma glucose and HbA1c concentrations increased with age, although the rate of increase differed between the tests. Total cholesterol and LDL-cholesterol concentrations increased with age, which became attenuated between the early 30s and late 50s in men, and declined thereafter. In women, total cholesterol and LDL-cholesterol concentrations gradually increased with age until late 30s, when there is an upward inflection, plateauing after late 50s. Our findings indicate that diagnostic performance of laboratory tests for diabetes may be age-sensitive. Unfavourable age-related cardiovascular risk profiles suggest that the burden of cardiovascular disease in this population will increase with aging population. PMID:27570971

  12. Quantification of age-related changes of α-tocopherol in lysosomal membranes in murine tissues and human fibroblasts.

    PubMed

    König, Jeannette; Besoke, Fabian; Stuetz, Wolfgang; Malarski, Angelika; Jahreis, Gerhard; Grune, Tilman; Höhn, Annika

    2016-05-01

    Considering the biological function of α-tocopherol (α-Toc) as a potent protective factor against oxidative stress, this antioxidant is in the focus of aging research. To understand the role of α-Toc during aging we investigated α-Toc concentrations in young and aged primary human fibroblasts after supplementation with RRR-α-Toc. Additionally, α-Toc contents were determined in brain, kidney, and liver tissue of 10 week-, 18 month-, and 24 month-old mice, which were fed a standard diet containing 100 mg/kg dl-α-tocopheryl acetate. α-Toc concentrations in isolated lysosomes and the expression of the α-Toc transport proteins Niemann Pick C1 (NPC1), Niemann Pick C2 (NPC2), and lipoprotein lipase were also analyzed. Obtained data show a significant age-related increase of α-Toc in murine liver, kidney, and brain tissue as well as in human dermal fibroblasts. Also liver and kidney lysosomes are marked by elevated α-Toc contents with aging. NPC1 and NPC2 protein amounts are significantly decreased in adult and aged murine kidney tissue. Also aged human dermal fibroblasts show decreased NPC1 amounts. Supplementation of young and aged fibroblasts led also to decreased NPC1 amounts, suggesting a direct role of this protein in α-Toc distribution. Our results indicate an age-dependent increase of α-Toc in different murine tissues as well as in human fibroblasts. Furthermore saturation and intracellular distribution of α-Toc seem to be strongly dependent on the availability of this vitamin as well as on the presence of the lysosomal protein NPC1. © 2016 BioFactors, 42(3):307-315, 2016.

  13. Age-Related Changes in the Cardiometabolic Profiles in Singapore Resident Adult Population: Findings from the National Health Survey 2010.

    PubMed

    Loh, Tze Ping; Ma, Stefan; Heng, Derrick; Khoo, Chin Meng

    2016-01-01

    We describe the centile trends of the blood pressure, glycemia and lipid profiles as well as renal function of a representative population who participated in the Singapore National Health Survey in 2010. Representative survey population was sampled in two phases, first using geographical/ residential dwelling type stratification, followed up ethnicity. 2,407 survey participants without any self-reported medical or medication history for diabetes mellitus, hypertension and dyslipidemia were included in this analysis. All biochemistry analyses were performed on Roche platforms. After excluding outliers using Tukey's criteria, the results of the remaining participants were subjected to lambda-mu-sigma (LMS) analysis. In men, systolic blood pressure increased linearly with age. By contrast, an upward inflection around late 40s was seen in women. The diastolic blood pressure was highest in men in the late 30s-50s age group, and in women in the late 50s-60s age group. All glycemia-related parameters, i.e. fasting and 2-hour plasma glucose and HbA1c concentrations increased with age, although the rate of increase differed between the tests. Total cholesterol and LDL-cholesterol concentrations increased with age, which became attenuated between the early 30s and late 50s in men, and declined thereafter. In women, total cholesterol and LDL-cholesterol concentrations gradually increased with age until late 30s, when there is an upward inflection, plateauing after late 50s. Our findings indicate that diagnostic performance of laboratory tests for diabetes may be age-sensitive. Unfavourable age-related cardiovascular risk profiles suggest that the burden of cardiovascular disease in this population will increase with aging population. PMID:27570971

  14. Analysis of Age-Related Changes in Asian Facial Skeletons Using 3D Vector Mathematics on Picture Archiving and Communication System Computed Tomography

    PubMed Central

    Kim, Soo Jin; Kim, So Jung; Park, Jee Soo; Byun, Sung Wan

    2015-01-01

    Purpose There are marked differences in facial skeletal characteristics between Asian and Caucasian. However, ethnic differences in age-related facial skeletal changes have not yet been fully established. The aims of this study were to evaluate age-related changes in Asian midfacial skeletons and to explore ethnic differences in facial skeletal structures with aging between Caucasian and Asian. Materials and Methods The study included 108 men (aged 20-79 years) and 115 women (aged 20-81 years). Axial CT images with a gantry tilt angle of 0 were analyzed. We measured three-dimensional (3D) coordinates at each point with a pixel lens cursor in a picture archiving and communication system (PACS), and angles and widths between the points were calculated using 3D vector mathematics. We analyzed angular changes in 4 bony regions, including the glabellar, orbital, maxillary, and pyriform aperture regions, and changes in the orbital aperture width (distance from the posterior lacrimal crest to the frontozygomatic suture) and the pyriform width (between both upper margins of the pyriform aperture). Results All 4 midfacial angles in females and glabellar and maxillary angles in males showed statistically significant decreases with aging. On the other hand, the orbital and pyriform widths did not show statistically significant changes with aging. Conclusion The results of this study suggest that Asian midfacial skeletons may change continuously throughout life, and that there may be significant differences in the midfacial skeleton between both sexes and between ethnic groups. PMID:26256986

  15. Children's Internal Attributions of Anxiety-Related Physical Symptoms: Age-Related Patterns and the Role of Cognitive Development and Anxiety Sensitivity

    ERIC Educational Resources Information Center

    Muris, Peter; Mayer, Birgit; Freher, Nancy Kramer; Duncan, Sylvana; van den Hout, Annemiek

    2010-01-01

    The present study examined age-related patterns in children's anxiety-related interpretations and internal attributions of physical symptoms. A large sample of 388 children aged between 4 and 13 years completed a vignette paradigm during which they had to explain the emotional response of the main character who experienced anxiety-related physical…

  16. Principal component structuring of the non-REM Sleep EEG spectrum in older adults yields age-related changes in the sleep and wake drives.

    PubMed

    Putilov, Arcady A; Münch, Mirjam Y; Cajochen, Christian

    2013-12-01

    Age-related disturbances of the sleep-wake cycle can reflect ontogenetic changes in regulatory mechanisms underlying normal and pathological aging, but the exact nature of these changes remains unclear. The present report is the first attempt to apply principal component analysis to the electroencephalographic (EEG) spectrum to examine of whether the observed age-related changes in the objective sleep measures can be linked to the opponent sleep-promoting and wake-promoting processes. The EEG indicators of these processes--scores on the 1st and 2nd principal components of the EEG spectrum, respectively--were compared in 15 older (57-74 years) and 16 younger (20-31 years) healthy volunteers. The scores were calculated for non-REM sleep episodes which occurred during ten 75-min naps scheduled every 150 min throughout a 40-h constant routine protocol. Both, a decrease of the 1st principal component score and an increase of the 2nd principal component score were found to contribute to such most obvious age-related modification of the sleep EEG spectrum as attenuation of EEG slow-wave activity in older people. Therefore, we concluded that the normal aging process can reflect both a weakening of the sleep-promoting process and a strengthening of the wake-promoting process, respectively. Such bidirectional changes in chronoregulatory processes may explain why sleep of older people is characterized by the few profitable and a number of detrimental features (i.e., a better ability to cope with daytime sleepiness and sleep loss vs. difficulty of falling asleep, decreased total nighttime sleep, "lightened" and fragmentized sleep, unwanted early morning awakenings, etc.).

  17. The senescence-accelerated prone mouse (SAMP8): a model of age-related cognitive decline with relevance to alterations of the gene expression and protein abnormalities in Alzheimer's disease.

    PubMed

    Butterfield, D Allan; Poon, H Fai

    2005-10-01

    The senescence-accelerated mouse (SAM) is an accelerated aging model that was established through phenotypic selection from a common genetic pool of AKR/J strain of mice. The SAM model was established in 1981, including nine major senescence-accelerated mouse prone (SAMP) substrains and three major senescence-accelerated mouse resistant (SAMR) substrains, each of which exhibits characteristic disorders. Recently, SAMP8 have drawn attention in gerontological research due to its characteristic learning and memory deficits at old age. Many recent reports provide insight into mechanisms of the cognitive impairment and pathological changes in SAMP8. Therefore, this mini review examines the recent findings of SAMP8 mice abnormalities at the gene and protein levels. The genes and proteins described in this review are functionally categorized into neuroprotection, signal transduction, protein folding/degradation, cytoskeleton/transport, immune response and reactive oxygen species (ROS) production. All of these processes are involved in learning and memory. Although these studies provide insight into the mechanisms that contribute to the learning and memory decline in aged SAMP8 mice, higher throughput techniques of proteomics and genomics are necessary to study the alterations of gene expression and protein abnormalities in SAMP8 mice brain in order to more completely understand the central nervous system dysfunction in this mouse model. The SAMP8 is a good animal model to investigate the fundamental mechanisms of age-related learning and memory deficits at the gene and protein levels. PMID:16026957

  18. Patient’s self-evaluation of two education programs for age-related skin changes in the face: a prospective, randomized, controlled study

    PubMed Central

    Williams, Linda M; Alderman, Jane E; Cussell, Garry; Goldston, John; Hamilton, Neal; Lim, Adrian C; Goodman, Greg J; Halstead, Michael B; Rogers, John D

    2011-01-01

    Background: An interactive software program (HOYS) has been developed utilizing a database of digital images depicting various aspects and degrees of aging of exposed skin across seven geographic regions, representing a total of 35 facial and extrafacial subregions. A five-point photonumeric rating scale, which portrays age-related skin changes across five decades for each of these subregions, underpins this patient-based interactive self-assessment program. Based on the resulting outputs from this program, an individualized treatment prioritization list is generated for each region where significant differences between the patient’s chronological and esthetic ages exist. This provides guidance for the patient and the treating physician on treatment options. Methods: To evaluate the utility of HOYS in the clinic, relative to education programs currently used in Australian private esthetic clinics, a total of 95 esthetically-orientated patients were enrolled in a prospective, randomized, controlled, multicenter study. Results: Compared with a prospective cohort of patients completing a standard education program commonly utilized in Australian esthetic clinics, patients receiving the HOYS education program reported greater empowerment through improved knowledge of specific age-related skin changes. This was associated with a clearer understanding of treatment options available to them, and a perceived ability to participate in the selection of the treatments potentially administered to improve their appearance. These differences between the two education groups were highly significant. Conclusion: Patients completing the HOYS patient education program have an improved understanding of age-related changes to exposed skin of their face, neck, décolletage, and hands. Due to the patient-specific nature of the program, these patients perceive a greater role in the deciding which esthetic treatments should be subsequently administered to enhance their appearance

  19. Oxidative stress and age-related changes in T cells: is thalassemia a model of accelerated immune system aging?

    PubMed Central

    Ghatreh-Samani, Mahdi; Esmaeili, Nafiseh; Soleimani, Masoud; Asadi-Samani, Majid; Ghatreh-Samani, Keihan

    2016-01-01

    Iron overload in β-thalassemia major occurs mainly due to blood transfusion, an essential treatment for β-thalassemia major patients, which results in oxidative stress. It has been thought that oxidative stress causes elevation of immune system senescent cells. Under this condition, cells normally enhance in aging, which is referred to as premature immunosenescence. Because there is no animal model for immunosenescence, most knowledge on the immunosenescence pattern is based on induction of immunosenescence. In this review, we describe iron overload and oxidative stress in β-thalassemia major patients and how they make these patients a suitable human model for immunosenescence. We also consider oxidative stress in some kinds of chronic virus infections, which induce changes in the immune system similar to β-thalassemia major. In conclusion, a therapeutic approach used to improve the immune system in such chronic virus diseases, may change the immunosenescence state and make life conditions better for β-thalassemia major patients. PMID:27095931

  20. Oxidative stress and age-related changes in T cells: is thalassemia a model of accelerated immune system aging?

    PubMed

    Ghatreh-Samani, Mahdi; Esmaeili, Nafiseh; Soleimani, Masoud; Asadi-Samani, Majid; Ghatreh-Samani, Keihan; Shirzad, Hedayatolah

    2016-01-01

    Iron overload in β-thalassemia major occurs mainly due to blood transfusion, an essential treatment for β-thalassemia major patients, which results in oxidative stress. It has been thought that oxidative stress causes elevation of immune system senescent cells. Under this condition, cells normally enhance in aging, which is referred to as premature immunosenescence. Because there is no animal model for immunosenescence, most knowledge on the immunosenescence pattern is based on induction of immunosenescence. In this review, we describe iron overload and oxidative stress in β-thalassemia major patients and how they make these patients a suitable human model for immunosenescence. We also consider oxidative stress in some kinds of chronic virus infections, which induce changes in the immune system similar to β-thalassemia major. In conclusion, a therapeutic approach used to improve the immune system in such chronic virus diseases, may change the immunosenescence state and make life conditions better for β-thalassemia major patients.

  1. Age-related transcriptional changes in gene expression in different organs of mice support the metabolic stability theory of aging.

    PubMed

    Brink, Thore C; Demetrius, Lloyd; Lehrach, Hans; Adjaye, James

    2009-10-01

    Individual differences in the rate of aging are determined by the efficiency with which an organism transforms resources into metabolic energy thus maintaining the homeostatic condition of its cells and tissues. This observation has been integrated with analytical studies of the metabolic process to derive the following principle: The metabolic stability of regulatory networks, that is the ability of cells to maintain stable concentrations of reactive oxygen species (ROS) and other critical metabolites is the prime determinant of life span. The metabolic stability of a regulatory network is determined by the diversity of the metabolic pathways or the degree of connectivity of genes in the network. These properties can be empirically evaluated in terms of transcriptional changes in gene expression. We use microarrays to investigate the age-dependence of transcriptional changes of genes in the insulin signaling, oxidative phosphorylation and glutathione metabolism pathways in mice. Our studies delineate age and tissue specific patterns of transcriptional changes which are consistent with the metabolic stability-longevity principle. This study, in addition, rejects the free radical hypothesis which postulates that the production rate of ROS, and not its stability, determines life span.

  2. Predicting cognitive change within domains

    PubMed Central

    Duff, Kevin; Beglinger, Leigh J.; Moser, David J.; Paulsen, Jane S.

    2010-01-01

    Standardized regression based (SRB) formulas, a method for predicting cognitive change across time, traditionally use baseline performance on a neuropsychological measure to predict future performance on that same measure. However, there are instances in which the same tests may not be given at follow-up assessments (e.g., lack of continuity of provider, avoiding practice effects). The current study sought to expand this methodology by developing SRBs to predict performance on different tests within the same cognitive domain. Using a sample of 127 non-demented community-dwelling older adults assessed at baseline and after one year, two sets of SRBs were developed: 1. those predicting performance on the same test, and 2. those predicting performance on a different test within the same cognitive domain. The domains examined were learning and memory, processing speed, and language. Across both sets of SRBs, one year scores were significantly predicted by baseline scores, especially for the learning and memory and processing speed measures. Although SRBs developed for the same test were comparable to those developed for different tests within the same domain, less variance was accounted for as tests became less similar. The current results lend preliminary support for additional development of SRBs, both for same- and different-tests, as well as beginning to examine domain-based SRBs. PMID:20358479

  3. Aging related changes in mixed basal saliva concentration of sodium, potassium and chloride in healthy non medicated humans.

    PubMed

    De Oliveira, Rui; Navas, Eunice; Duran, Carolina; Pinto, Maria; Gutierrez, Jose; Eblen-Zajjur, Antonio

    2014-01-01

    It is well known that the salivary flow is reduced by aging but ionic composition changes associated to aging have been less evaluated. To measure salivary and plasmatic [Na(+)], [K(+)] and [Cl(-)] and to correlate with age in healthy, non-medicated subjects of any gender, 165 healthy participating subjects (over 15 years old) were asked to give sample of 5 mL mix basal saliva in a plastic vial without any stimulation technique, additionally, 5 mL of venous blood was collected. Samples [Na(+)] and [K(+)] were measured by flame photometry (Corning™ M-405) and [Cl(-)] by voltametric chlorometry (Corning™ M-920). Ionic concentrations were expressed as (X±DE; meq.L⁻¹). All three ionic concentrations progressively increased with age, with the lineal regression equation being: [Na(+)] mEq=17.76 + 0.26(Age); r=+0.42; F=31.5; P=0.00001; [K(+)] mEq=13.2+0.15(Age); r=+0.32; F=16.5; P=0.00001; [Cl(-)] mEq=9.05+0.18(Age); r=+0.35; F=7.8; P=0.0071. Age induced changes in salivary ionic concentrations were not associated to blood ionic changes. However, saliva and blood [Na(+)] and [K(+)] were correlated (r=+0.25; F=4.49; P=0.04 and r=+0.30; F=6.98; P=0.01, respectively). Significant association was found among salivary ions: [Na(+)] mEq=9.14+0.99[K(+)] (r=+0.79; F=95.2; P=0.000001); [Cl(-)] mEq=0.95+0.56[Na(+)] (r=0.79; F=106.6; P=0.000001) and [Cl(-)] mEq=3.45+0.69[K(+)] (r=0.73; F=72.5; P=0.000001). These results confirm and measure the impact of aging over the mixed and resting salivary secretion process and suggest that local changes are not related to blood ionic composition. PMID:25101709

  4. Age-related changes of the noradrenergic and acetylcholinesterase reactive nerve fibres innervating the pigeon bursa of Fabricius.

    PubMed

    Ciriaco, E; Ricci, A; Bronzetti, E; Mammola, C L; Germanà, G; Vega, J A

    1995-05-01

    Age-dependent changes in the innervation of the pigeon (Columba livia, L.) bursa of Fabricius, from hatching to 120 days of age, were studied by fluorescence-histochemical and neurochemical methods for demonstrating noradrenergic and acetylcholinesterase (AChE)-reactive nerve fibres respectively. The distribution of both nerve fibre types was largely perivascular. Furthermore, a few isolated nerve fiber profiles were observed beneath the bursal epithelium, in the interfollicular septa and in the follicular cortex. No nerve fibre profiles reaching the medulla of the lymphoid follicles were observed. In addition to nerve fibres, AChE reactive neuron-like cells were encountered within the capsule and interfollicular septa. AChE reactivity was also found in dendritic-like cells localized in the cortical and cortico-medullary border. No changes in the density of perivascular noradrenergic innervation were noticeable during the ages studied, whereas the density of AChE-reactive fibres supplying vessels reached the adult pattern at 30 days, and then remained unvaried. The density of non-perivascular nerve fiber profiles, specially the AChE reactive type, increased until 30 days, remained unchanged until 75 days and then increased with aging (90-120 days). The interrelationship between the autonomic nervous system and the immune system is discussed.

  5. Age-related changes in intramuscular and subcutaneous fat content and fatty acid composition in growing pigs using longitudinal data.

    PubMed

    Bosch, L; Tor, M; Reixach, J; Estany, J

    2012-07-01

    The evolution of intramuscular fat (IMF) and subcutaneous backfat (SB) content and fatty acid composition with age was investigated. A repeated sampling scheme (n=517) for longissimus dorsi (LM) and SB specimens was performed from 160 to 220 days on 216 purebred Duroc barrows. IMF content increased linearly with age at a rate of 0.05%/day, with major compositional changes occurring in C18:1 and C18.2, which increased and decreased by around 4%, respectively. Backfat thickness increase rate declined with age, showing similar compositional changes to IMF but halved in magnitude. Fat content itself also influenced fat composition. At a fixed age, both saturated (SFA) (C16:0) and monounsaturated (MUFA) (C18:1) increased with IMF but only SFA (C16:0 and C18:0) with SB. Aging mostly affected MUFA while fatness SFA. A delay in age at slaughter will enhance IMF and C18:1 in relation to overall fatness but at expense of decreasing body and loin growth rate.

  6. Characterization of stroke- and aging-related changes in the complexity of EMG signals during tracking tasks.

    PubMed

    Ao, Di; Sun, Rui; Tong, Kai-Yu; Song, Rong

    2015-04-01

    To explore the stroke- and aging-induced neurological changes in paretic muscles from an entropy point of view, fuzzy approximate entropy (fApEn) was utilized to represent the complexity of EMG signals in elbow-tracking tasks. In the experiment, 11 patients after stroke and 20 healthy control subjects (10 young and 10 age-matched adults) were recruited and asked to perform elbow sinusoidal trajectory tracking tasks. During the tests, the elbow angle and electromyographic (EMG) signals of the biceps brachii and triceps brachii were recorded simultaneously. The results showed significant differences in fApEn values of both biceps and triceps EMG among four groups at six velocities (p < 0.01), with fApEn values in the following order: affected sides of stroke patients < unaffected sides of stroke patients < age-matched controls < young controls. A possible mechanism underlying the smaller fApEn values in the affected sides in comparison with aged-matched controls and in the aged individuals in comparison with young controls might be the reduction in the number and firing rate of active motor units. This method and index provide evidence of neurological changes after stroke and aging by complexity analysis of the surface EMG signals. Further studies are needed to validate and facilitate the application in clinic.

  7. Season- and Age-related Reproductive Changes Based on Fecal Androgen Concentrations in Male Koalas, Phascolarctos cinereus

    PubMed Central

    KUSUDA, Satoshi; HASHIKAWA, Hisashi; TAKEDA, Masato; ITO, Hideki; GOTO, Atsushi; OGUCHI, Jun; DOI, Osamu

    2013-01-01

    Abstract The purposes of the present study were to clarify age- and season- related androgen patterns, and to compare the reproductive physiology between Japanese captive koala populations and Australian populations. To measure fecal androgens, feces were collected from male koalas (4.2 to 13.8 years of age) kept in Japanese zoos. Fecal androgens were extracted with methanol from the lyophilized samples and determined by enzyme immunoassay using 4-androstene-3,17-dione antibody. Fecal androgen concentration in male koalas increased after sexual maturation and remained relatively high until old age. In the survey with the Japanese zoo studbook of koalas, copulation (conception) month showed a pyramid shape with a peak in March to June (60.7%) in koalas born and reared in Japanese zoos and from July to April with the highest concentration in September to January (69.7%) in Australian institutes. Japanese zoo koala populations have a characteristic physiological cycle adapted to Japan's seasonal changes. The suitable month of year for copulation or conception in Japan is diametrically opposed to that in Australia. Mean fecal androgen concentrations by month in the males born and reared in Japan indicated annual changes with the highest concentration in May and the lowest value in November. Fecal androgen analysis may be a noninvasive alternative tool to monitor circulating testosterone and may be helpful in understanding reproductive activity and physiology in male koalas. PMID:23502854

  8. Developmental changes in the perception of syllable-final stop voicing are not explained by age-related differences in auditory sensitivity

    NASA Astrophysics Data System (ADS)

    Nittrouer, Susan

    2001-05-01

    Two cues to voicing decisions for syllable-final stops are vocalic duration and formant transitions, especially F1, at syllable offset. Developmental studies show that children weight vocalic duration less and formant transitions more than adults. This study tested the hypothesis that age-related differences in auditory sensitivity can explain these developmental changes by measuring adults' and children's sensitivities to changes in the duration of nonspeech, complex tones and analogous speech stimuli. The durations of three-tone sinusoidal stimuli and natural cob and cop were varied. Duration difference limens (DLs) were similar for listeners across ages, and similar for nonspeech and speech. Also, the extent of frequency fall was varied in three-tone sinusoidal stimuli for the first tone (T1) only or for all three tones, as well as for F1 only in synthetic buck/bug. DLs for frequency extent were similar for listeners across ages for nonspeech stimuli when all three tones fell, but children had larger DLs than adults when only T1 or F1 fell, a finding contrary to labeling results showing that children weight this very property more than adults. Overall the evidence contradicted the hypothesis that age-related differences in auditory sensitivity can explain developmental changes in the perception of syllable-final stop voicing.

  9. [FTIR microspectroscopic investigation of the age-related changes of subchondral bone of the knee in guinea pig].

    PubMed

    Yang, Li-ping; Liu, Jian-ling; Song, Qing-hui; Zhu, Jia; Zhang, Wan-qiang; Kong, Huan-yu; Zhao, Tie-jun

    2013-09-01

    Fourier transform infrared (FTIR) microspectroscopy was applied to in-situ analyse the chemical change of tibial articular subchondral bone of female Hartley guinea pigs with age increase. Three infrared absorption regions (a, b, c) of trabecular bone and central marrow region of the subchondral bone were measured for guinea pigs of different ages (1 months, 2 months and 3 months) using the infrared spectrum. Results show that (1) with months increasing, the total area of trabecular bone is increasing, meanwhile, the region a which is similar to normal trabecular bone spectra is decreasing, and region d waveform has the same trend as region a. (2) In the second and third month, region b & c show amide Ill redshift and the red shift in region c shows a shoulder peak, showing the absorption peak intensity on behalf of nucleic acid and polysaccharide in region b & c is 7 times that in region a. (3) beta glycosidic bond absorption peak appears at region c in 3 different old pigs. (4) I(amide III) / I(amide II) is the highest in region b in the second month but lowest in the third month; I(amide III) / I(amide II) reduces from a to c in the second and third month; I(upsilon3)PO2- / I(amide II) in region b & c is 7 times higher than region a in the second and third Month These results are consistent with the regular pattern of change rule of osteoarthritis subchondral bone's organization structure and chemical composition in different stages. Our primary result illustrated that FTIR microspectroscopy can be used for in-situ analysis of the molecular organization of subchondral trabecular bone and bone marrow. It provides reliable pathology information for osteoarthritis subchondral bone tissue at molecular level.

  10. [FTIR microspectroscopic investigation of the age-related changes of subchondral bone of the knee in guinea pig].

    PubMed

    Yang, Li-ping; Liu, Jian-ling; Song, Qing-hui; Zhu, Jia; Zhang, Wan-qiang; Kong, Huan-yu; Zhao, Tie-jun

    2013-09-01

    Fourier transform infrared (FTIR) microspectroscopy was applied to in-situ analyse the chemical change of tibial articular subchondral bone of female Hartley guinea pigs with age increase. Three infrared absorption regions (a, b, c) of trabecular bone and central marrow region of the subchondral bone were measured for guinea pigs of different ages (1 months, 2 months and 3 months) using the infrared spectrum. Results show that (1) with months increasing, the total area of trabecular bone is increasing, meanwhile, the region a which is similar to normal trabecular bone spectra is decreasing, and region d waveform has the same trend as region a. (2) In the second and third month, region b & c show amide Ill redshift and the red shift in region c shows a shoulder peak, showing the absorption peak intensity on behalf of nucleic acid and polysaccharide in region b & c is 7 times that in region a. (3) beta glycosidic bond absorption peak appears at region c in 3 different old pigs. (4) I(amide III) / I(amide II) is the highest in region b in the second month but lowest in the third month; I(amide III) / I(amide II) reduces from a to c in the second and third month; I(upsilon3)PO2- / I(amide II) in region b & c is 7 times higher than region a in the second and third Month These results are consistent with the regular pattern of change rule of osteoarthritis subchondral bone's organization structure and chemical composition in different stages. Our primary result illustrated that FTIR microspectroscopy can be used for in-situ analysis of the molecular organization of subchondral trabecular bone and bone marrow. It provides reliable pathology information for osteoarthritis subchondral bone tissue at molecular level. PMID:24369633

  11. Age related changes in pelvis size among adolescent and adult females with reference to parturition from Naraingarh, Haryana (India).

    PubMed

    Sharma, Krishan; Gupta, Puneet; Shandilya, Shailza

    2016-08-01

    This research examines the ontogenic patterns of changes in growth during adolescence, pelvis variations and growth during twenties and thirties of age, structural remodeling of pelvis related to childbirth and relationship of pelvis area with physique based on the cross-sectional data on 391 females from the state of Haryana. Peak growth velocity for body height and breadths of skeletal traits occurred between 11 and 12 years, much before mean age of menarche at 13.5 years; while for body weight and body mass index (BMI) occurred between 14 and 15 years, after the mean age of menarche. Untill the age 11 years, 11.87% of growth in stature was remaining, 19.37% for bi-cristal breadth, 25.96% for bi-ischial breadth and 35.82% for pelvic area. The hypothesis of critical value of pelvic width of 240mm at iliocristale for menarche to occur has been only a statistical association. Higher prevalence of malnutrition during pubertal phase than pre- and post-pubertal phases was due to greater nutritional needs during puberty. Among adult females, BMI was very poorly correlated with stature but very strongly correlated with body breadths, body breadth-stature indices and body weight. The body mass and pelvis size continued to change during 20s and first half of 30s. The continued increase of BMI was due to increase in body fat and muscle mass in females 18 years and older. To tease apart age and parturition effects on pelvis variations, the analysis showed that pelvic bones remodeling took place after the first child was born and not after the subsequent births, and it was a sign of childbirth phenotypic plasticity rather than age. Pelvis area was strongly associated with stature, BMI and age. Mean pelvic area of tall females was greater than those of medium and short stature. Females with broad shoulders had significantly greater mean pelvis area than those with narrow shoulders and medium shoulders. Females having thin/lean physique had the smallest mean pelvis area

  12. Ginkgo biloba extract EGb 761® in the context of current developments in the diagnosis and treatment of age-related cognitive decline and Alzheimer's disease: a research perspective.

    PubMed

    Lautenschlager, Nicola T; Ihl, Ralf; Müller, Walter E

    2012-08-01

    In June 2011 a two-day expert meeting "The Ageing Brain" took place in Amsterdam, The Netherlands. The main aim was to discuss the available preclinical and clinical data on Ginkgo biloba special extract EGb 761® in the context of current developments in the diagnosis and treatment of age-related cognitive decline and Alzheimer's disease. 19 dementia experts covering the disciplines bio- and neurochemistry, gerontology, neurology, pharmacology, and psychiatry from Australia, Asia, Europe and North America reviewed available preclinical and clinical data for EGb 761® and identified core topics for future research. Based on a wide range of preclinical effects demonstrated for Ginkgo biloba, EGb 761® can be conceptualized as a multi-target compound with activity on distinct pathophysiological pathways in Alzheimer's disease (AD) and age-related cognitive decline. While symptomatic efficacy in dementia and mild cognitive impairment (MCI) has been demonstrated, interpretation of data from dementia prevention trials is complicated by important methodological issues. Bridging pre-clinical research and clinical research as well as deciding on suitable study designs for future trials with EGb 761® remain important questions. The participants of the "Ageing Brain" meeting on Ginkgo biloba special extract EGb 761® concluded that there is plenty of promising data, both pre-clinical and clinical, to consider future research with the compound targeting cognitive impairment in old age as a worthwhile activity.

  13. Age-related changes in soma size of neurons in the spinal cord motor column of the cat.

    PubMed

    Liu, R H; Bertolotto, C; Engelhardt, J K; Chase, M H

    1996-06-28

    The present study was undertaken to examine the effect of the aging process on the soma size and number of motoneurons and interneurons in the motor column of the spinal cord of old cats. Neurons in the motor column were divided into small and large populations based on a bimodal distribution of their soma cross-sectional areas. A 17% decrease in the cross-sectional area of small neurons was observed, this decrease was statistically significant (P < 0.0001). The cross-sectional area of large neurons decreased by only 6%, which was statistically significant (P < 0.05). On the other hand, there was no significant difference in the number of large, small or of these combined population of ventral horn neurons in the aged cats compared with the control animals. This data suggest that neurons in the motor column are not uniformly affected by the aging process because morphological changes are proportionally greater in small neurons than in large neurons. PMID:8817566

  14. Progressive age-related changes in sleep and EEG profiles in the PLB1Triple mouse model of Alzheimer's disease.

    PubMed

    Jyoti, Amar; Plano, Andrea; Riedel, Gernot; Platt, Bettina

    2015-10-01

    Sleep disturbances are common in Alzheimer's disease (AD) and now assumed to contribute to disease onset and progression. Here, we investigated whether activity, sleep/wake pattern, and electroencephalogram (EEG) profiles are altered in the knock-in PLB1Triple mouse model from 5 to 21 months of age. PLB1Triple mice displayed a progressive increase in wakefulness and non-rapid eye movement sleep fragmentation from 9 months onward, whereas PLB1WT wild type controls showed such deterioration only at 21 months. Impaired habituation to spatial novelty was also detected in PLB1Triple mice. Hippocampal power spectra of transgenic mice revealed progressive, vigilance stage-, brain region-, and age-specific changes. Age had an impact on EEG spectra in both cohorts but led to accelerated genotype-dependent differences, ultimately affecting all bands at 21 months. Overall, although PLB1Triple animals display only subtle amyloid and tau pathologies, robust sleep-wake and EEG abnormalities emerged. We hypothesize that such endophenotypes are sensitive, noninvasive, and reliable biomarker to identify onset and progression of AD.

  15. A preliminary study of pores on epidermal ridges: Are there any sex differences and age related changes?

    PubMed

    Nagesh, K R; Bathwal, Shikha; Ashoka, B

    2011-10-01

    The pore characteristics on the epidermal friction ridges are individualistic and thereby useful in the process of identification when used along with other minutiae details. The present work was undertaken with the objective of studying the sex difference and influence of age on the pore morphology. The study included 230 Indians belonging to various age groups. There was no significant difference in the pore characteristics between both the sexes. The average number of pores per centimeter of friction ridge was 8.40 in males and 8.83 in females. The closed type was the commonest type of pores seen. The size of pores varied from 69 μm to 284 μm in males and 66 μm-287 μm in females. The medium-sized pores were more common than the small and large-sized pores. The majority of the pores were situated in the periphery of the ridge. The commonest shape of pores seen was circular and oval shaped pores. As the age advances, the number of pores does not significantly vary. But, the size gradually increases, and the position and shape of pores changes with the age.

  16. Age-related change in the multiple unit activity of the rat brain parietal cortex and the effect of centrophenoxine.

    PubMed

    Roy, D; Singh, R

    1988-01-01

    In this study, spontaneous multiple unit activity (MUA, action potentials derived simultaneously from a number of neurons in a given brain region) was recorded through electrodes chronically implanted in the parietal cerebral cortex of the rats of 1, 3, 6, 9, 12, and 26 months of age (cross-sectional study). Electrophysiological recordings were obtained from unrestrained conscious rats using standard techniques. The results indicated that multiple unit activity was decreased with aging (senescence). Maximum firing rate (MUA counts) was found at the age of 3 months. At 6 months of age, the MUA was decreased by about 30%, while during 6 to 12 months of age the activity seemed to remain unchanged. At 26 months of age the firing rate was, however, further decreased (about 40%). Centrophenoxine administration led to an increase in MUA in the rats of 12 and 26 months of age. The results, thus, further showed that centrophenoxine, a nootropic drug known for its antiaging effects in experimental animals as well as in humans, also manifested beneficial effects electrophysiologically. The data presented in this work are new and significant, since although age effects on gross electrophysiological signals (EEG, evoked potentials, etc.) are known, the aging changes in cellular level electrophysiological signals (action potentials) have not been generally studied particularly in conscious animals.

  17. Age-Related Changes to Human Stratum Corneum Lipids Detected Using Time-of-Flight Secondary Ion Mass Spectrometry Following in Vivo Sampling.

    PubMed

    Starr, Nichola J; Johnson, Daniel J; Wibawa, Judata; Marlow, Ian; Bell, Mike; Barrett, David A; Scurr, David J

    2016-04-19

    This work demonstrates the ability to detect changes in both quantity and spatial distribution of human stratum corneum (SC) lipids from samples collected in vivo. The SC functions as the predominant barrier to the body, protecting against the penetration of xenobiotic substances. Changes to the SC lipid composition have been associated with barrier impairment and consequent skin disorders, and it is therefore important to monitor and quantify changes to this structure. This work demonstrates the first reported use of time-of-flight secondary ion mass spectrometry (ToF-SIMS) to assess physiological changes to human SC as a function of depth. This technique provides exceptional sensitivity and chemical specificity, allowing analysis of single tape stripped samples taken from volunteers. Using this methodology we were able to successfully identify chemical differences in human SC resulting from both intrinsic and extrinsic (photo) aging. Samples were collected from women of two age groups (under 27 and postmenopausal) and from two body sites with varying UV exposure (inner forearm and dorsal hand), and differences were identified using multivariate data analysis. The key finding was the significant aged-related increase and change in spatial distribution of the sterol cholesterol sulfate, a membrane stabilizing lipid. Significant changes in the prevalence of both lignoceric acid (C24:0) and hexacosanoic acid (C26:0) were also observed. This work describes previously unreported age-related chemical changes to human SC, providing an insight into aging mechanisms which may improve the design of both pharmaceutical and cosmetic topical products. PMID:27010630

  18. Age-related neuroinflammation and changes in AKT-GSK-3β and WNT/ β-CATENIN signaling in rat hippocampus

    PubMed Central

    Orellana, Ana Maria Marques; Vasconcelos, Andrea Rodrigues; Leite, Jacqueline Alves; de Sá Lima, Larissa; Andreotti, Diana Zukas; Munhoz, Carolina Demarchi; Kawamoto, Elisa Mitiko; Scavone, Cristoforo

    2015-01-01

    Aging is a multifactorial process associated with an increased susceptibility to neurodegenerative disorders which can be related to chronic inflammation. Chronic inflammation, however, can be characterized by the persistent elevated glucocorticoid (GCs) levels, activation of the proinflammatory transcription factor NF-кB, as well as an increase in cytokines. Interestingly, both NF-кB and cytokines can be even modulated by Glycogen Synthase Kinase 3 beta (GSK-3β) activity, which is a key protein that can intermediate inflammation and metabolism, once it has a critical role in AKT signaling pathway, and can also intermediate WNT/β-CATENIN signaling pathway. The aim of this study was to verify age-related changes in inflammatory status, as well as in the AKT and WNT signaling pathways. Results showed an age-related increase in neuroinflammation as indicated by NF-кB activation, TNF-α and GCs increased levels, a decrease in AKT activation and an increase in GSK-3β activity in both 12- and 24- month old animals. Aging also seems to induce a progressive decrease in canonical WNT/β-CATENIN signaling pathway once there is a decrease in DVL-2 levels and in the transcription of Axin2 gene. Little is known about the DVL-2 regulation as well as its roles in WNT signaling pathway, but for the first time it was suggested that DVL-2 expression can be changed along aging. PMID:26647069

  19. Age-related neuroinflammation and changes in AKT-GSK-3β and WNT/ β-CATENIN signaling in rat hippocampus.

    PubMed

    Orellana, Ana Maria Marques; Vasconcelos, Andrea Rodrigues; Leite, Jacqueline Alves; de Sá Lima, Larissa; Andreotti, Diana Zukas; Munhoz, Carolina Demarchi; Kawamoto, Elisa Mitiko; Scavone, Cristoforo

    2015-12-01

    Aging is a multifactorial process associated with an increased susceptibility to neurodegenerative disorders which can be related to chronic inflammation. Chronic inflammation, however, can be characterized by the persistent elevated glucocorticoid (GCs) levels, activation of the proinflammatory transcription factor NF-кB, as well as an increase in cytokines. Interestingly, both NF-кB and cytokines can be even modulated by Glycogen Synthase Kinase 3 beta (GSK-3β) activity, which is a key protein that can intermediate inflammation and metabolism, once it has a critical role in AKT signaling pathway, and can also intermediate WNT/β-CATENIN signaling pathway. The aim of this study was to verify age-related changes in inflammatory status, as well as in the AKT and WNT signaling pathways. Results showed an age-related increase in neuroinflammation as indicated by NF-кB activation, TNF-α and GCs increased levels, a decrease in AKT activation and an increase in GSK-3β activity in both 12- and 24- month old animals. Aging also seems to induce a progressive decrease in canonical WNT/β-CATENIN signaling pathway once there is a decrease in DVL-2 levels and in the transcription of Axin2 gene. Little is known about the DVL-2 regulation as well as its roles in WNT signaling pathway, but for the first time it was suggested that DVL-2 expression can be changed along aging.

  20. Self-serving appraisal as a cognitive coping strategy to deal with age-related limitations: an empirical study with elderly adults in a real-life stressful situation.

    PubMed

    De Raedt, Rudi; Ponjaert-Kristoffersen, I

    2006-03-01

    Elderly people are often confronted with stressful events that threaten psychological homeostasis. Nevertheless, the lack of a general age-related drop in life satisfaction remains intriguing. The objective of this study was to analyze the basic mechanisms of perceived control and self-protective processes. Eighty-four elderly adults who underwent a fitness-to-drive evaluation were asked how they appraised their performance in a driving simulation task and were classified as over-estimators versus people who estimated their performance correctly and people who didn't overestimate their performance. Decreased physical resources were related to self-serving appraisal and less depressive feelings. The results are in line with theories on self-immunizing processes and provide support for the use of cognitive therapies in dealing with age-related limitations.

  1. Dopaminergic modulation of incentive motivation in adolescence: age-related changes in signaling, individual differences, and implications for the development of self-regulation

    PubMed Central

    Luciana, Monica; Wahlstrom, Dustin; Porter, James N.; Collins, Paul F.

    2012-01-01

    Behavioral activation that is associated with incentive-reward motivation increases in adolescence relative to childhood and adulthood. This quadratic developmental pattern is generally supported by behavioral and experimental neuroscience findings. We suggest that a focus on changes in dopamine neurotransmission is informative in understanding the mechanism for this adolescent increase in reward-related behavioral activation and subsequent decline into adulthood. We present evidence to indicate that incentive-reward motivation is modulated by mesoaccumbens dopamine and that it increases in adolescence before declining into adulthood due to normative developmental changes at the molecular level. Potential mechanisms of variation in functional mesoaccumbens dopamine transmission are discussed with a focus on the interplay between tonic and phasic modes of DA transmission in modulating both general incentive-motivational biases and the efficacy of reward learning during exposure to novel reward experiences. Interactions between individual difference factors and these age-related trends are discussed. PMID:22390660

  2. Comparison of age-related changes in in vivo and in vitro measures of testicular steroidogenesis after acute cadmium exposure in the sprague-dawley rat

    SciTech Connect

    Phelps, P.V.; Laskey, J.W.

    1989-01-01

    Previous reports have demonstrated that cadmium- induced testicular necrosis is an age-dependent process. However, little information exists on age-related intestitial cell (IC) damage in the rat after acute exposure to Cd. In-vitro and in-vivo measures of testicular damage were utilized to compare the sensitivity of these measures and to further investigate age-related Cd-induced testicular damage. Testes, epididymides, and seminal-vesicle weights, serum testosterone (sT), hCG-stimulated sT, and basal and stimulated IC testosterone (T) production were compared in rats 21 d following an injection of 2 mg Cd/kg at 9, 37, 67, and 97 d of age. The only Cd-related change noted for immature rats was an 84% reduction in sT. In rats injected when 37 d old, hCG-stimulated sT and epididymides and seminal-vesicle weights, although depressed, were not significantly altered. However, all other measurements were significantly depressed. All measures of testicular damage were significantly depressed in rats injected at 67 and 97 d of age. Overall, in vitro measures were more sensitive indicators of Cd-induced testicular damage than in vivo measures.

  3. Effects of intermittent fasting on age-related changes on Na,K-ATPase activity and oxidative status induced by lipopolysaccharide in rat hippocampus.

    PubMed

    Vasconcelos, Andrea Rodrigues; Kinoshita, Paula Fernanda; Yshii, Lidia Mitiko; Marques Orellana, Ana Maria; Böhmer, Ana Elisa; de Sá Lima, Larissa; Alves, Rosana; Andreotti, Diana Zukas; Marcourakis, Tania; Scavone, Cristoforo; Kawamoto, Elisa Mitiko

    2015-05-01

    Chronic neuroinflammation is a common characteristic of neurodegenerative diseases, and lipopolysaccharide (LPS) signaling is linked to glutamate-nitric oxide-Na,K-ATPase isoforms pathway in central nervous system (CNS) and also causes neuroinflammation. Intermittent fasting (IF) induces adaptive responses in the brain that can suppress inflammation, but the age-related effect of IF on LPS modulatory influence on nitric oxide-Na,K-ATPase isoforms is unknown. This work compared the effects of LPS on the activity of α1,α2,3 Na,K-ATPase, nitric oxide synthase gene expression and/or activity, cyclic guanosine monophosphate, 3-nitrotyrosine-containing proteins, and levels of thiobarbituric acid-reactive substances in CNS of young and older rats submitted to the IF protocol for 30 days. LPS induced an age-related effect in neuronal nitric oxide synthase activity, cyclic guanosine monophosphate, and levels of thiobarbituric acid-reactive substances in rat hippocampus that was linked to changes in α2,3-Na,K-ATPase activity, 3-nitrotyrosine proteins, and inducible nitric oxide synthase gene expression. IF induced adaptative cellular stress-response signaling pathways reverting LPS effects in rat hippocampus of young and older rats. The results suggest that IF in both ages would reduce the risk for deficits on brain function and neurodegenerative disorders linked to inflammatory response in the CNS. PMID:25818175

  4. High resolution magnetic resonance imaging of the calcaneus: age-related changes in trabecular structure and comparison with dual X-ray absorptiometry measurements

    NASA Technical Reports Server (NTRS)

    Ouyang, X.; Selby, K.; Lang, P.; Engelke, K.; Klifa, C.; Fan, B.; Zucconi, F.; Hottya, G.; Chen, M.; Majumdar, S.; Genant, H. K.

    1997-01-01

    A high-resolution magnetic resonance imaging (MRI) protocol, together with specialized image processing techniques, was applied to the quantitative measurement of age-related changes in calcaneal trabecular structure. The reproducibility of the technique was assessed and the annual rates of change for several trabecular structure parameters were measured. The MR-derived trabecular parameters were compared with calcaneal bone mineral density (BMD), measured by dual X-ray absorptiometry (DXA) in the same subjects. Sagittal MR images were acquired at 1.5 T in 23 healthy women (mean age: 49.3 +/- 16.6 [SD]), using a three-dimensional gradient echo sequence. Image analysis procedures included internal gray-scale calibration, bone and marrow segmentation, and run-length methods. Three trabecular structure parameters, apparent bone volume (ABV/TV), intercept thickness (I.Th), and intercept separation (I.Sp) were calculated from the MR images. The short- and long-term precision errors (mean %CV) of these measured parameters were in the ranges 1-2% and 3-6%, respectively. Linear regression of the trabecular structure parameters vs. age showed significant correlation: ABV/TV (r2 = 33.7%, P < 0.0037), I.Th (r2 = 26.6%, P < 0.0118), I.Sp (r2 = 28.9%, P < 0.0081). These trends with age were also expressed as annual rates of change: ABV/TV (-0.52%/year), I.Th (-0.33%/year), and I.Sp (0.59%/year). Linear regression analysis also showed significant correlation between the MR-derived trabecular structure parameters and calcaneal BMD values. Although a larger group of subjects is needed to better define the age-related changes in trabecular structure parameters and their relation to BMD, these preliminary results demonstrate that high-resolution MRI may potentially be useful for the quantitative assessment of trabecular structure.

  5. Lithocholic bile acid accumulated in yeast mitochondria orchestrates a development of an anti-aging cellular pattern by causing age-related changes in cellular proteome

    PubMed Central

    Beach, Adam; Richard, Vincent R; Bourque, Simon; Boukh-Viner, Tatiana; Kyryakov, Pavlo; Gomez-Perez, Alejandra; Arlia-Ciommo, Anthony; Feldman, Rachel; Leonov, Anna; Piano, Amanda; Svistkova, Veronika; Titorenko, Vladimir I

    2015-01-01

    We have previously revealed that exogenously added lithocholic bile acid (LCA) extends the chronological lifespan of the yeast Saccharomyces cerevisiae, accumulates in mitochondria and alters mitochondrial membrane lipidome. Here, we use quantitative mass spectrometry to show that LCA alters the age-related dynamics of changes in levels of many mitochondrial proteins, as well as numerous proteins in cellular locations outside of mitochondria. These proteins belong to 2 regulons, each modulated by a different mitochondrial dysfunction; we call them a partial mitochondrial dysfunction regulon and an oxidative stress regulon. We found that proteins constituting these regulons (1) can be divided into several “clusters”, each of which denotes a distinct type of partial mitochondrial dysfunction that elicits a different signaling pathway mediated by a discrete set of transcription factors; (2) exhibit 3 different patterns of the age-related dynamics of changes in their cellular levels; and (3) are encoded by genes whose expression is regulated by the transcription factors Rtg1p/Rtg2p/Rtg3p, Sfp1p, Aft1p, Yap1p, Msn2p/Msn4p, Skn7p and Hog1p, each of which is essential for longevity extension by LCA. Our findings suggest that LCA-driven changes in mitochondrial lipidome alter mitochondrial proteome and functionality, thereby enabling mitochondria to operate as signaling organelles that orchestrate an establishment of an anti-aging transcriptional program for many longevity-defining nuclear genes. Based on these findings, we propose a model for how such LCA-driven changes early and late in life of chronologically aging yeast cause a stepwise development of an anti-aging cellular pattern and its maintenance throughout lifespan. PMID:25839782

  6. Age-related changes in frequency of mind-wandering and task-related interferences during memory encoding and their impact on retrieval.

    PubMed

    Maillet, David; Rajah, M Natasha

    2013-01-01

    During the performance of cognitive tasks such as memory encoding, attention can become decoupled from the external environment and instead focused on internal thoughts related to the appraisal of the current task (task-related interferences; TRI), or personal thoughts unrelated to the task at hand (mind-wandering; MW). However, the association between the frequency of these thoughts experienced at encoding and retrieval accuracy in young and older adults remains poorly understood. In this study young and older adults encoded lists of words using one of two encoding tasks: judging whether words are man-made/natural (objective task), or whether they are pleasant/neutral (subjective task). We measured the frequency of TRI and MW at encoding, and related them to retrieval accuracy in both age groups. We found that encoding task influenced the type of internal thoughts experienced by young, but not older, adults: young exhibited greater MW in the subjective vs the objective task, and greater TRI in the objective vs subjective encoding task. Second, across both tasks we found marked age-related decreases in both MW and TRI at encoding, and frequency of these thoughts negatively impacted memory retrieval in young adults only. We discuss these findings in relation to current theories of ageing, attention and memory.

  7. The Role of Sensory Modality in Age-Related Distraction: A Critical Review and a Renewed View

    ERIC Educational Resources Information Center

    Guerreiro, Maria J. S.; Murphy, Dana R.; Van Gerven, Pascal W. M.

    2010-01-01

    Selective attention requires the ability to focus on relevant information and to ignore irrelevant information. The ability to inhibit irrelevant information has been proposed to be the main source of age-related cognitive change (e.g., Hasher & Zacks, 1988). Although age-related distraction by irrelevant information has been extensively…

  8. Current evidence for the clinical use of long-chain polyunsaturated n-3 fatty acids to prevent age-related cognitive decline and Alzheimer's disease.

    PubMed

    Dacks, P A; Shineman, D W; Fillit, H M

    2013-03-01

    An NIH State of the Science Conference panel concluded in 2010 that insufficient evidence is available to recommend the use of any primary prevention therapy for Alzheimer's disease or cognitive decline with age. Despite the insufficient evidence, candidate therapies with varying levels of evidence for safety and efficacy are taken by the public and discussed in the media. One example is the long-chain n-3 (omega-3) polyunsaturated fatty acids (n-3 LC-PUFA), DHA and EPA, found in some fish and dietary supplements. With this report, we seek to provide a practical overview and rating of the level and type of available evidence that n-3 LC-PUFA supplements are safe and protective against cognitive aging and Alzheimer's disease, with additional discussion of the evidence for effects on quality of life, vascular aging, and the rate of aging. We discuss available sources, dose, bioavailability, and variables that may impact the response to n-3 LC-PUFA treatment such as baseline n-3 LC-PUFA status, APOE ε4 genotype, depression, and background diet. Lastly, we list ongoing clinical trials and propose next research steps to validate these fatty acids for primary prevention of cognitive aging and dementia. Of particular relevance, epidemiology indicates a higher risk of cognitive decline in people in the lower quartile of n-3 LC-PUFA intake or blood levels but these populations have not been specifically targeted by RCTs. PMID:23459977

  9. Current evidence for the clinical use of long-chain polyunsaturated n-3 fatty acids to prevent age-related cognitive decline and Alzheimer's disease.

    PubMed

    Dacks, P A; Shineman, D W; Fillit, H M

    2013-03-01

    An NIH State of the Science Conference panel concluded in 2010 that insufficient evidence is available to recommend the use of any primary prevention therapy for Alzheimer's disease or cognitive decline with age. Despite the insufficient evidence, candidate therapies with varying levels of evidence for safety and efficacy are taken by the public and discussed in the media. One example is the long-chain n-3 (omega-3) polyunsaturated fatty acids (n-3 LC-PUFA), DHA and EPA, found in some fish and dietary supplements. With this report, we seek to provide a practical overview and rating of the level and type of available evidence that n-3 LC-PUFA supplements are safe and protective against cognitive aging and Alzheimer's disease, with additional discussion of the evidence for effects on quality of life, vascular aging, and the rate of aging. We discuss available sources, dose, bioavailability, and variables that may impact the response to n-3 LC-PUFA treatment such as baseline n-3 LC-PUFA status, APOE ε4 genotype, depression, and background diet. Lastly, we list ongoing clinical trials and propose next research steps to validate these fatty acids for primary prevention of cognitive aging and dementia. Of particular relevance, epidemiology indicates a higher risk of cognitive decline in people in the lower quartile of n-3 LC-PUFA intake or blood levels but these populations have not been specifically targeted by RCTs.

  10. Age-related changes in the dynamics of potassium-evoked L-glutamate release in the striatum of Fischer 344 rats.

    PubMed

    Nickell, J; Pomerleau, F; Allen, J; Gerhardt, G A

    2005-01-01

    In the present studies we used a multisite ceramic-based microelectrode for rapid (800 ms) and low level measures of L-glutamate in vivo. We measured the amplitude and clearance rate of phasic changes in L-glutamate release produced by local application of potassium by a micropipette placed adjacent to the recording sites in the striatum of young (6 month), late middle aged (18 month) and aged (24 month) Fischer 344 rats. Our results showed that the amplitudes and clearance rates of potassium-evoked release of L-glutamate in the striatum were significantly decreased in aged rats as compared to the other age groups. In addition, the sensitivity of glutamate fibers to depolarization with potassium was significantly decreased in the aged rats as compared to young animals. Taken together, these data are consistent with age-related alterations in glutamate release dynamics, which may involve a compensatory mechanism for maintaining static glutamate concentrations within the striatum.

  11. Thyroid metabolism in the recessive sex-linked dwarf female chicken. 1. Age related changes in thyroid hormone synthesis and circulating thyroid hormone levels.

    PubMed

    Grandhi, R R; Brown, R G

    1975-03-01

    Age related changes in the levels of circulating thyroid hormones as well as the type of hormones synthesized in the thyroid glands from normal and sex-linked recessive dwarf, female chickens were studied. The impact of the presence of the dwarf gene on the parameters measured was minimal but significant alterations in the types of hormones produced in the thyroid gland with increasing age were observed. As the birds approached sexual maturity, the synthesis of triiodothyronine increased sharply such that the ratio of triiodothyronine (T3): tetraiodothyronine (T4) was approximately 15:1. This was in contrast to the T3:T4 ratio of younger birds which was approximately 0.7:1.0. This shift in hormone synthesis was reflected in relatively more circulating T3 in laying hens when compared with younger birds. It was also noted that four week old dwarf birds had higher circulating T3 values than those found for the normals.

  12. Age-related Changes in Acoustic Modifications of Mandarin Maternal Speech to Preverbal Infants and Five-Year-Old Children: A Longitudinal Study

    PubMed Central

    Liu, Huei-Mei; Tsao, Feng-Ming; Kuhl, Patricia K.

    2010-01-01

    Acoustic-phonetic exaggeration of infant-directed speech (IDS) is well documented, but few studies address whether these features are modified with a child's age. Mandarin-speaking mothers were recorded while addressing an adult and their child at two ages (7-12 months and 5 years) to examine the acoustic-phonetic differences between IDS and child–directed speech (CDS). CDS exhibits an exaggeration pattern resembling that of IDS—expanded vowel space, longer vowels, higher pitch, and greater lexical tone differences—when compared to ADS. Longitudinal analysis demonstrated that the extent of acoustic exaggeration is significantly smaller in CDS than in IDS. Age-related changes in maternal speech provide some support for the hypothesis that mothers adjust their speech directed toward children as a function of the child's language ability. PMID:19232142

  13. Assessment of Age-Related Morphometric Changes of Subcortical Structures in Healthy People Using Ultra-High Field 7 Tesla Magnetic Resonance Imaging

    PubMed Central

    Wang, Xue-Yuan; Zhao, Lei; Yu, Tao; Qiao, Liang; Ni, Duan-Yu; Zhang, Guo-Jun; Li, Yong-Jie

    2016-01-01

    Objective: To assess the age-related morphometric changes of subcortical structures in healthy people. Materials and Methods: Ultra-high field 7 tesla magnetic resonance (MR) imaging in humans was used to visualize the subcortical structures of healthy young, middle-aged and elderly participants. Using the magnetization-prepared two rapid acquisition gradient echo (MP2RAGE) sequence, we assessed the visibility of the margins of the thalamus and white matter in the thalamus, as well as the anterior commissure (AC) and posterior commissure (PC) length, the maximal height of the thalamus, the half width of the third ventricle and the distance between the AC and the center of the mammillothalamic tract (MTT) at the level of the AC-PC plane. All quantitative data were statistically evaluated. Results: The AC-PC length did not differ significantly among the three groups. The maximal height of the thalamus decreased with age (rs(53) = −0.719, p < 0.001). The half width of the third ventricle (rs(53) = 0.705, p < 0.001) and the distance between the AC and the center of the MTT (rs(53) = 0.485, p < 0.001) increased with age. The distance between the AC and the center of the MTT of the young and the elderly participants differed significantly (p = 0.007). Conclusion: The AC-PC length is not a good candidate for proportional correction during atlas-to-patient registration. The maximal height of the thalamus and the half width of the third ventricle correlated strongly with age, and the MTT position in relation to the AC shifted posteriorly as age increased. These age-related morphometric changes of subcortical structures should be considered in targeting for functional neurosurgery. PMID:27725800

  14. Aging, frailty and age-related diseases.

    PubMed

    Fulop, T; Larbi, A; Witkowski, J M; McElhaney, J; Loeb, M; Mitnitski, A; Pawelec, G

    2010-10-01

    The concept of frailty as a medically distinct syndrome has evolved based on the clinical experience of geriatricians and is clinically well recognizable. Frailty is a nonspecific state of vulnerability, which reflects multisystem physiological change. These changes underlying frailty do not always achieve disease status, so some people, usually very elderly, are frail without a specific life threatening illness. Current thinking is that not only physical but also psychological, cognitive and social factors contribute to this syndrome and need to be taken into account in its definition and treatment. Together, these signs and symptoms seem to reflect a reduced functional reserve and consequent decrease in adaptation (resilience) to any sort of stressor and perhaps even in the absence of extrinsic stressors. The overall consequence is that frail elderly are at higher risk for accelerated physical and cognitive decline, disability and death. All these characteristics associated with frailty can easily be applied to the definition and characterization of the aging process per se and there is little consensus in the literature concerning the physiological/biological pathways associated with or determining frailty. It is probably true to say that a consensus view would implicate heightened chronic systemic inflammation as a major contributor to frailty. This review will focus on the relationship between aging, frailty and age-related diseases, and will highlight possible interventions to reduce the occurrence and effects of frailty in elderly people. PMID:20559726

  15. APOL1 Risk Alleles Are Associated with Exaggerated Age-Related Changes in Glomerular Number and Volume in African-American Adults: An Autopsy Study.

    PubMed

    Hoy, Wendy E; Hughson, Michael D; Kopp, Jeffrey B; Mott, Susan A; Bertram, John F; Winkler, Cheryl A

    2015-12-01

    APOL1 genetic variants contribute to kidney disease in African Americans. We assessed correlations between APOL1 profiles and renal histological features in subjects without renal disease. Glomerular number (N glom) and mean glomerular volume (V glom) were measured by the dissector/fractionator method in kidneys of African-American and non-African-American adults without renal disease, undergoing autopsies in Jackson, Mississippi. APOL1 risk alleles were genotyped and the kidney findings were evaluated in the context of those profiles. The proportions of African Americans with none, one, and two APOL1 risk alleles were 38%, 43%, and 19%, respectively; 38% of African Americans had G1 allele variants and 31% of African Americans had G2 allele variants. Only APOL1-positive African Americans had significant reductions in N glom and increases in V glom with increasing age. Regression analysis predicted an annual average loss of 8834 (P=0.03, sex adjusted) glomeruli per single kidney over the first 38 years of adult life in African Americans with two risk alleles. Body mass index above the group medians, but below the obesity definition of ≥ 30 kg/m(2), enhanced the expression of age-related changes in N glom in African Americans with either one or two APOL1 risk alleles. These findings indicate that APOL1 risk alleles are associated with exaggerated age-related nephron loss, probably decaying from a larger pool of smaller glomeruli in early adult life, along with enlargement of the remaining glomeruli. These phenomena might mark mechanisms of accentuated susceptibility to kidney disease in APOL1-positive African Americans.

  16. Comparison of age-related changes in in vivo and in vitro measures of testicular steroidogenesis after acute cadmium exposure in the sprague-dawley rat

    SciTech Connect

    Phelps, P.V.; Laskey, J.W. )

    1989-01-01

    Previous reports have demonstrated that cadmium- (Cd-) induced testicular necrosis is an age-dependent process. However, little information exists on age-related intestitial cell (IC) damage in the rat after acute exposure to Cd. In this study in vitro and in vivo measures of testicular damage were utilized to compare the sensitivity of these measures and to further investigate age-related Cd-induced testicular damage. Testes, epididymides, and seminal vesicle weights, serum testosterone (sT), hCG-stimulated sT, and basal and stimulated IC testosterone (T) production were production were compared in rats 21 d following an injection of 2 mg Cd/kg at 9, 37, 67, and 97 d of age. The only Cd-related change noted for immature rats was an 84% reduction in sT. In rats injected when 37 d old, hCG-stimulated sT and epididymides and seminal vesicle weights, although depressed, were not significantly altered. However, all other measurements were significantly depressed. All measures of testicular damage were significantly depressed in rats injected at 67 and 97 d of age. Overall, in vitro measures were more sensitive indicators of Cd-induced testicular damage than in vivo measures. However, sT and hCG-stimulated sT appeared to be useful indicators of Cd effects on the pituitary-gonadal axis. ICs from immature rats (9 d old) were unaffected by Cd exposure, while stimulated T reproduction in ICs from 37-, 67-, and 97-d-old animals was reduced at least 50%. The severity of Cd-induced testicular damage increases with age for all variables measured.

  17. Age-related changes in insulin sensitivity and β-cell function among European-American and African-American women.

    PubMed

    Chandler-Laney, Paula C; Phadke, Radhika P; Granger, Wesley M; Fernández, José R; Muñoz, Julian A; Man, Chiara Dalla; Cobelli, Claudio; Ovalle, Fernando; Gower, Barbara A

    2011-03-01

    Type 2 diabetes (T2D) is more prevalent among African-American (AA) than European-American (EA) women for reasons that are unknown. Ethnic differences in physiological processes related to insulin sensitivity (S(I)) and secretion, and age-related changes in these processes, may play a role. The purpose of this study was to identify ethnicity- and age-related differences in S(I) and β-cell responsivity among AA and EA females, and to determine whether these differences are independent of body composition and fat distribution. Healthy, normoglycemic females aged 7-12 years (n = 62), 18-32 years (n = 57), and 40-70 years (n = 49) were recruited for entry into this study. Following an overnight fast, S(I), intravenous glucose tolerance (Kg), acute C-peptide secretion (X0), and basal, first-phase, second-phase, and total β-cell responsivity to glucose (PhiB, Phi1, Phi2, and Phi(TOT), respectively) were measured by an intravenous glucose tolerance test. Total % body fat was assessed by dual-energy X-ray absorptiometry, and intra-abdominal adiposity (IAAT) by computed tomography. Main effects of age group and ethnicity were measured with analysis of covariance, adjusting for % fat, IAAT, and S(I) as indicated. AA had lower S(I), and higher Kg, X0, Phi1, and Phi(TOT) (P < 0.05), which remained after adjustment for % fat and IAAT. Greater X0, Phi1, and Phi(TOT) among AA were independent of S(I). Advancing age was associated with greater Phi2 among both EA and AA. To conclude, inherent ethnic differences in β-cell function exist independently of adiposity and S(I). Future research should examine whether ethnic differences in β-cell physiology contribute to disparities in T2D risk.

  18. Altered Hippocampal Transcript Profile Accompanies an Age-Related Spatial Memory Deficit in Mice

    ERIC Educational Resources Information Center

    Verbitsky, Miguel; Yonan, Amanda L.; Malleret, Gael; Kandel, Eric R.; Gilliam, T. Conrad; Pavlidis, Paul

    2004-01-01

    We have carried out a global survey of age-related changes in mRNA levels in the 57BL/6NIA mouse hippocampus and found a difference in the hippocampal gene expression profile between 2-month-old young mice and 15-month-old middle-aged mice correlated with an age-related cognitive deficit in hippocampal-based explicit memory formation. Middle-aged…

  19. Age-related changes in the concentrations of cytosol receptors for sex steroid hormones in the hypothalamus and pituitary gland of the rat.

    PubMed

    Haji, M; Kato, K I; Nawata, H; Ibayashi, H

    1981-01-12

    Estrogen and androgen receptors were measured in cytosols from hypothalamus, pituitary and uterus or prostate of rats at 3 stages in life, from 90 to 650 days old in females and from 90 to 550 days old in males. Saturation analysis of cytosol 17 beta-estradiol receptors in females demonstrated a significant age-associated reduction in maximum binding capacity in hypothalamus and uterus already at 300-330 days of life, but there was no significant change in pituitary gland. However, there was no difference in binding affinity, steroid specificity, sedimentation coefficient, chemical nature and heat lability of cytosol 17 beta-estradiol binding of these tissues among the 3 age groups. In males, each receptor for 17 beta-estradiol, testosterone and 5 alpha-dihydrotestosterone was isolated by sucrose density gradient centrifugation from hypothalamic, pituitary and prostate cytosols. These receptors showed the same sedimentation coefficient of 8-9S in all age groups. Androgen binding by cytosols already decreased at 300-330 days of life, but estrogen binding was lower at 500-550 days of life than in younger adults. The increase in the serum luteinizing hormone level after gonadectomy was significantly depressed with aging in both females and males. These findings suggested that the age-associated reduction in cytosol sex steroid hormone receptors was ascribable to changes of numbers of binding sites. These age-related changes may be concerned with feedback system dysfunction of hypothalamic-pituitary-gonadal axis in aged rats.

  20. Age-related Multiscale Changes in Brain Signal Variability in Pre-task versus Post-task Resting-state EEG.

    PubMed

    Wang, Hongye; McIntosh, Anthony R; Kovacevic, Natasa; Karachalios, Maria; Protzner, Andrea B

    2016-07-01

    Recent empirical work suggests that, during healthy aging, the variability of network dynamics changes during task performance. Such variability appears to reflect the spontaneous formation and dissolution of different functional networks. We sought to extend these observations into resting-state dynamics. We recorded EEG in young, middle-aged, and older adults during a "rest-task-rest" design and investigated if aging modifies the interaction between resting-state activity and external stimulus-induced activity. Using multiscale entropy as our measure of variability, we found that, with increasing age, resting-state dynamics shifts from distributed to more local neural processing, especially at posterior sources. In the young group, resting-state dynamics also changed from pre- to post-task, where fine-scale entropy increased in task-positive regions and coarse-scale entropy increased in the posterior cingulate, a key region associated with the default mode network. Lastly, pre- and post-task resting-state dynamics were linked to performance on the intervening task for all age groups, but this relationship became weaker with increasing age. Our results suggest that age-related changes in resting-state dynamics occur across different spatial and temporal scales and have consequences for information processing capacity. PMID:26942319

  1. "Older is always better": Age-related differences in vocabulary scores across 16 years.

    PubMed

    Ben-David, Boaz M; Erel, Hadas; Goy, Huiwen; Schneider, Bruce A

    2015-12-01

    Cross-sectional studies of cognitive aging compare age groups at 1 time point. It is unclear from such studies whether age-related cognitive differences remain stable across time. We present a cross-sectional investigation of vocabulary scores of 2,000 younger and older adults collected across 16 years, using the same laboratory and protocol. We found a steady decrease with year of testing and an advantage for older adults. An additive relation between age group and year of testing implied that age-related differences in vocabulary are independent of changes over time, suggesting that younger and older adults are similarly affected by changes in word usage.

  2. Cognition through the lifespan: mechanisms of change.

    PubMed

    Craik, Fergus I M; Bialystok, Ellen

    2006-03-01

    Cognitive abilities rise steeply from infancy to young adulthood and then are either maintained or decline to old age, depending on the specific ability. This pattern suggests corresponding continuities of mechanism and process, but it is striking that the fields of cognitive development and cognitive aging make little contact with each other's methods and theories. In this review we examine reasons for this cultural separation, and show how recent findings from both areas fit a framework couched in terms of cognitive representation and control. These two broad factors have very different lifespan trajectories; consideration of their relative growth and decline makes it clear that cognitive aging is not simply 'development in reverse'. This framework is offered in light of recent interest in finding greater continuity throughout the lifespan and creating a more comprehensive explanation of cognitive function and cognitive change.

  3. Age-related changes in the behavioural response of honeybees to Apiguard®, a thymol-based treatment used to control the mite Varroa destructor.

    PubMed

    Mondet, Fanny; Goodwin, Mark; Mercer, Alison

    2011-11-01

    The parasitic mite Varroa destructor is responsible for heavy losses in honey bee colonies and represents a major threat to the beekeeping industry. Essential oils offer an attractive alternative to the use of synthetic chemicals for the control of varroa. Amongst them, thymol appears to be particularly promising. However, treatments using thymol as their active substance, such as the gel formulation Apiguard(®), are suspected to have adverse effects on honey bee colonies. In this study, laboratory assays are used to investigate the effects of Apiguard(®) exposure on honey bee behaviour. Our results reveal that honey bee responses to this anti-varroa treatment change with honey bee age. While 2-day-old bees respond neutrally to Apiguard(®), older bees generally avoid the Apiguard(®) gel. Responses of forager bees were particularly striking. Foragers appear to be repelled by Apiguard(®). Touching their antennae with Apiguard(®) induces robust fanning behaviour. Our data suggest, however, that forager bees exposed to Apiguard(®) in the hive can become habituated to this treatment. These results offer interesting new perspectives on the effects of Apiguard(®) on honey bee behaviour and serve to highlight age-related changes in honey bee responses to gustatory, as well as olfactory cues.

  4. Cognitive training-related changes in hippocampal activity associated with recollection in older adults

    PubMed Central

    Kirchhoff, Brenda A.; Anderson, Benjamin A.; Smith, Staci E.; Barch, Deanna M.; Jacoby, Larry L.

    2013-01-01

    Impairments in the ability to recollect specific details of personally experienced events are one of the main cognitive changes associated with aging. Cognitive training can improve older adults’ recollection. However, little is currently known regarding the neural correlates of these training-related changes in recollection. Prior research suggests that the hippocampus plays a central role in supporting recollection in young and older adults, and that age-related changes in hippocampal function may lead to age-related changes in recollection. The present study investigated whether cognitive training-related increases in older adults’ recollection are associated with changes in their hippocampal activity during memory retrieval. Older adults’ hippocampal activity during retrieval was examined before and after they were trained to use semantic encoding strategies to intentionally encode words. Training-related changes in recollection were positively correlated with training-related changes in activity for old words in the hippocampus bilaterally. Positive correlations were also found between training-related changes in activity in prefrontal and left lateral temporal regions associated with self-initiated semantic strategy use during encoding and training-related changes in right hippocampal activity associated with recollection during retrieval. These results suggest that cognitive training-related improvements in older adults’ recollection can be supported by changes in their hippocampal activity during retrieval. They also suggest that age differences in cognitive processes engaged during encoding are a significant contributor to age differences in recollection during retrieval. PMID:22728150

  5. Cognitive Impairment and Age-Related Vision Disorders: Their Possible Relationship and the Evaluation of the Use of Aspirin and Statins in a 65 Years-and-Over Sardinian Population

    PubMed Central

    Mandas, Antonella; Mereu, Rosa Maria; Catte, Olga; Saba, Antonio; Serchisu, Luca; Costaggiu, Diego; Peiretti, Enrico; Caminiti, Giulia; Vinci, Michela; Casu, Maura; Piludu, Stefania; Fossarello, Maurizio; Manconi, Paolo Emilio; Dessí, Sandra

    2014-01-01

    Neurological disorders (Alzheimer’s disease, vascular and mixed dementia) and visual loss (cataract, age-related macular degeneration, glaucoma, and diabetic retinopathy) are among the most common conditions that afflict people of at least 65 years of age. An increasing body of evidence is emerging, which demonstrates that memory and vision impairment are closely, significantly, and positively linked and that statins and aspirin may lessen the risk of developing age-related visual and neurological problems. However, clinical studies have produced contradictory results. Thus, the intent of the present study was to reliably establish whether a relationship exist between various types of dementia and age-related vision disorders, and to establish whether statins and aspirin may or may not have beneficial effects on these two types of disorders. We found that participants with dementia and/or vision problems were more likely to be depressed and displayed worse functional ability in basic and instrumental activities of daily living than controls. Mini mental state examination scores were significantly lower in patients with vision disorders compared to subjects without vision disorders. A closer association with macular degeneration was found in subjects with Alzheimer’s disease than in subjects without dementia or with vascular dementia, mixed dementia, or other types of age-related vision disorders. When we considered the associations between different types of dementia and vision disorders and the use of statins and aspirin, we found a significant positive association between Alzheimer’s disease and statins on their own or in combination with aspirin, indicating that these two drugs do not appear to reduce the risk of Alzheimer’s disease or improve its clinical evolution and may, on the contrary, favor its development. No significant association in statin use alone, aspirin use alone, or the combination of these was found in subjects without vision

  6. Cognitive Impairment and Age-Related Vision Disorders: Their Possible Relationship and the Evaluation of the Use of Aspirin and Statins in a 65 Years-and-Over Sardinian Population.

    PubMed

    Mandas, Antonella; Mereu, Rosa Maria; Catte, Olga; Saba, Antonio; Serchisu, Luca; Costaggiu, Diego; Peiretti, Enrico; Caminiti, Giulia; Vinci, Michela; Casu, Maura; Piludu, Stefania; Fossarello, Maurizio; Manconi, Paolo Emilio; Dessí, Sandra

    2014-01-01

    Neurological disorders (Alzheimer's disease, vascular and mixed dementia) and visual loss (cataract, age-related macular degeneration, glaucoma, and diabetic retinopathy) are among the most common conditions that afflict people of at least 65 years of age. An increasing body of evidence is emerging, which demonstrates that memory and vision impairment are closely, significantly, and positively linked and that statins and aspirin may lessen the risk of developing age-related visual and neurological problems. However, clinical studies have produced contradictory results. Thus, the intent of the present study was to reliably establish whether a relationship exist between various types of dementia and age-related vision disorders, and to establish whether statins and aspirin may or may not have beneficial effects on these two types of disorders. We found that participants with dementia and/or vision problems were more likely to be depressed and displayed worse functional ability in basic and instrumental activities of daily living than controls. Mini mental state examination scores were significantly lower in patients with vision disorders compared to subjects without vision disorders. A closer association with macular degeneration was found in subjects with Alzheimer's disease than in subjects without dementia or with vascular dementia, mixed dementia, or other types of age-related vision disorders. When we considered the associations between different types of dementia and vision disorders and the use of statins and aspirin, we found a significant positive association between Alzheimer's disease and statins on their own or in combination with aspirin, indicating that these two drugs do not appear to reduce the risk of Alzheimer's disease or improve its clinical evolution and may, on the contrary, favor its development. No significant association in statin use alone, aspirin use alone, or the combination of these was found in subjects without vision disorders but

  7. Age-related changes in the induction of tyrosine aminotransferase by dexamethasone: correlation with the low-affinity glucocorticoid binding sites.

    PubMed

    Chirino, R; Fernández, L; López-Guerra, A; Valerón, P F; Navarro, D; Díaz-Chico, J C; Díaz-Chico, B N

    1994-09-01

    Rat liver membranes contain Low-affinity glucocorticoid binding sites (LAGS), capable of binding with low affinity (Kd approximately 100 nM) endogenous glucocorticoids. Unlike the glucocorticoid receptor (GR), the LAGS level undergoes abrupt changes throughout life. The investigation of these changes may be useful in determining whether the LAGS are involved in the cellular response to glucocorticoids. For this purpose, we have studied glucocorticoid induction of tyrosine aminotransferase (TAT), and its relationship with the LAGS level in adrenalectomized and fasted rats of different ages. No significant differences in the GR level, or in its Kd and activation, were observed among rats of 1, 3, and 12 months of age. On the other hand, the LAGS level showed an important variation with age, from almost undetectable in 1-month-old rats, to a maximum value in 3-month-old rats. With respect to TAT activity, an increase with age in the threshold of response to dexamethasone (DEX) administration was observed. The smallest dose of DEX capable of provoking a significant TAT induction rose from 0.1 microgram/kg body wt. in 1-month-old rats to 10 micrograms/kg body wt. in 12-month-old rats. However, the smallest dose of DEX able to elicit the maximal response was 10 micrograms/kg body wt. in all the assayed ages. This dose provoked a 40% decrease in the GR level, but did not significantly modify the LAGS content. From these results, we conclude that there is an age-related change in the threshold of response to DEX that cannot be explained by the GR-glucocorticoid interaction. The possibility that the LAGS modulate the cell response to glucocorticoids arises from the coincidence of this change with that observed in the LAGS concentration throughout life.

  8. Age-related changes of vertical and horizontal lumbar vertebral trabecular 3D bone microstructure is different in women and men.

    PubMed

    Thomsen, Jesper Skovhus; Niklassen, Andreas Steenholt; Ebbesen, Ebbe Nils; Brüel, Annemarie

    2013-11-01

    The study presents a 3D method for subdividing a trabecular network into horizontal and vertical oriented bone. This method was used to investigate the age related changes of the bone volume fraction and thickness of horizontal and vertical trabeculae in human lumbar vertebral bone estimated with unbiased 3D methods in women and men over a large age-range. The study comprised second lumbar vertebral body bone samples from 40 women (aged 21.7-96.4years, median 56.6years) and 39 men (aged 22.6-94.6years, median 55.6years). The bone samples were μCT scanned and the 3D microstructure was quantified. A voxel based algorithm inspecting the local neighborhood is presented and used to segment the trabecular network into horizontal and vertical oriented bone. For both women and men BV/TV decreased significantly with age, Tb.Th* was independent of age, while SMI increased significantly with age. Vertical (BV.vert/TV) and horizontal (BV.horz/TV) bone volume fraction decreased significantly with age for both sexes. BV.vert/TV decreased significantly faster with age for women than for men. Vertical (Tb.Th*.vert) and horizontal (Tb.Th*.horz) trabecular thickness were independent of age, while Tb.Th*.horz/Tb.Th*.vert decreased significantly with age for both sexes. Additionally, the 95th percentile of the trabecular thickness distribution increased significantly with age for vertical trabeculae in women, whereas it was independent of age in men. In conclusion, we have shown that vertical and horizontal oriented bone density decreases with age in both women and men, and that vertical oriented bone is lost more quickly in women than in men. Furthermore, vertical and horizontal trabecular thickness were independent of age, whereas the horizontal to vertical trabecular thickness ratio decreased significantly with age indicating a relatively more pronounced thinning of horizontal trabeculae. Finally, the age-related loss of trabecular elements appeared to result in a compensatory

  9. Age-related change of the mean level and intraindividual variability of saccadic reaction time performance in persons with intellectual disabilities.

    PubMed

    Haishi, Koichi; Okuzumi, Hideyuki; Kokubun, Mitsuru

    2013-03-01

    The current study examined age-related change of saccadic reaction time (SRT) in persons with intellectual disabilities (ID). Participants were 29 persons with intellectual disabilities aged between 14 and 34 years whose IQs were between 14 and 70. Participants were divided into Group I (IQ≧35) and Group II (IQ≦34). The mean and the standard deviation of SRT (SRTM and SRTSD, respectively) reduced through adolescence in both groups. This result suggests that the speed and stability of information processing develops during adolescence irrespective of the level of ID. Although SRTM and SRTSD of Group I stabilized after adolescence, those of Group II increased after their thirties. This outcome indicates that persons with severe ID may show signs of the aging process. The results of multiple regression analyses and path analyses indicated that SRTM was influenced by both the speed of information processing and the variability of the response. However, given that the extent of increase of SRTSD in Group II was smaller as compared with that of SRTM, this increase of SRTM after the thirties in Group II appears to be mainly affected by the slowness of information processing. PMID:23291514

  10. Age-related changes in executive function: A normative study with the Dutch version of the Behavior Rating Inventory of Executive Function (BRIEF).

    PubMed

    Huizinga, Mariëtte; Smidts, Diana P

    2011-01-01

    This study examined age-related change in executive function by using a Dutch translation of the Behavior Rating Inventory of Executive Function (BRIEF; Gioia et al., 2000) that was applied to a normative sample (age range 5-18 years). In addition, we examined the reliability and factorial structures of the Dutch BRIEF. Results with respect to age revealed a decrease in reported executive function problems with increasing age. On the Behavior Regulation Index (BRI), 5- to 8-year-olds showed significantly more executive function problems than 9- to 11-year-olds, as did the 12- to 14-year-olds compared to 15- to 18-year-olds (except on the Shift subscale). On the Metacognition Index, we found that 9- to 11-year-olds differed significantly from 5- to 8-year-olds on the Working Memory subscale. In addition, the current study showed that the internal consistency of the Dutch BRIEF is very high, and that this version of the BRIEF has a high test-retest stability. Item factor analysis confirmed the expected eight common factor model, and factor analysis of the eight test scores confirmed the two-factor model, as proposed by Gioia et al., in the Dutch data.

  11. Assessing Age-Related Changes in the Biomechanical Properties of Rabbit Lens Using a Coaligned Ultrasound and Optical Coherence Elastography System

    PubMed Central

    Wu, Chen; Han, Zhaolong; Wang, Shang; Li, Jiasong; Singh, Manmohan; Liu, Chih-hao; Aglyamov, Salavat; Emelianov, Stanislav; Manns, Fabrice; Larin, Kirill V.

    2015-01-01

    Purpose. To evaluate the capability of a novel, coaligned focused ultrasound and phase-sensitive optical coherence elastography (US-OCE) system to assess age-related changes in biomechanical properties of the crystalline lens in situ. Methods. Low-amplitude elastic deformations in young and mature rabbit lenses were measured by an US-OCE system consisting of a spectral-domain optical coherence tomography (OCT) system coaligned with a focused ultrasound system used to produce a transient force on the lens surface. Uniaxial compressional tests were used to validate the OCE data. Results. The OCE measurements showed that the maximum displacements of the young rabbit lenses were significantly larger than those of the mature lenses, indicating a gradual increase of the lens stiffness with age. Temporal analyses of the displacements also demonstrate a similar trend of elastic properties in these lenses. The stress-strain measurements using uniaxial mechanical tests confirmed the results obtained by the US-OCE system. Conclusions. The results demonstrate that the US-OCE system can be used for noninvasive analysis and quantification of lens biomechanical properties in situ and possibly in vivo. PMID:25613945

  12. Cognitive Status and Change among Iowa Centenarians

    ERIC Educational Resources Information Center

    Margrett, Jennifer A.; Hsieh, Wen-Hua; Heinz, Melinda; Martin, Peter

    2012-01-01

    Equivocal evidence exists regarding the degree of cognitive stability and prevalence of cognitive impairment in very late life. The objective of the current study was to examine mental status performance and change over time within a sample of Iowa centenarians. The baseline sample consisted of 152 community-dwelling and institutionalized…

  13. Cognitive decline is mediated by gray matter changes during middle age.

    PubMed

    Ferreira, Daniel; Molina, Yaiza; Machado, Alejandra; Westman, Eric; Wahlund, Lars-Olof; Nieto, Antonieta; Correia, Rut; Junqué, Carme; Díaz-Flores, Lucio; Barroso, José

    2014-05-01

    The present theoretical framework of Alzheimer's disease proposes that pathophysiological changes occur 10-20 years before the diagnosis of dementia. We addressed the question of how age-related changes in gray matter mediate the cognitive performance during middle age. Eighty-two participants (40-50 years, ±2) were assessed with a comprehensive neuropsychological battery covering a broad spectrum of cognitive domains and components. Mediation effects were studied with hierarchical regression and bootstrapping analysis. Results showed that more vulnerable cognitive components were related to executive functioning and in a lesser degree to processing speed. Age-related differences in gray matter mainly involved the frontal lobes. Moreover, age-related differences in visuoconstructive, visuospatial functions, reaction time, and mental flexibility and executive control were mediated by several gray matter regions. It is important to increase the knowledge of the impact of brain changes on cognitive function during middle age. To define the early stages of the aging process may allow early detection of pathologic changes and therapeutic interventions.

  14. Cognitive Development and Down Syndrome: Age-Related Change on the Stanford-Binet Test (Fourth Edition)

    ERIC Educational Resources Information Center

    Couzens, Donna; Cuskelly, Monica; Haynes, Michele

    2011-01-01

    Growth models for subtests of the Stanford-Binet Intelligence Scale, 4th edition (R. L. Thorndike, E. P. Hagen, & J. M. Sattler, 1986a, 1986b) were developed for individuals with Down syndrome. Models were based on the assessments of 208 individuals who participated in longitudinal and cross-sectional research between 1987 and 2004. Variation in…

  15. Cognitive development and Down syndrome: age-related change on the Stanford-Binet test (fourth edition).

    PubMed

    Couzens, Donna; Cuskelly, Monica; Haynes, Michele

    2011-05-01

    Growth models for subtests of the Stanford-Binet Intelligence Scale, 4th edition ( R. L. Thorndike, E. P. Hagen, & J. M. Sattler, 1986a , 1986b ) were developed for individuals with Down syndrome. Models were based on the assessments of 208 individuals who participated in longitudinal and cross-sectional research between 1987 and 2004. Variation in performance among individuals was large and significant across all subtests except Memory for Sentences. Scores on the Memory for Sentences subtest remained low between ages 4 to 30 years. Greatest variation was found on the Pattern Analysis subtest, where scores continued to rise into adulthood. Turning points for scores on the Vocabulary and Comprehension subtests appeared premature relative to normative patterns of development. The authors discuss development at the subdomain level and analyze both individual and group trajectories.

  16. Developmental Change and the Multidimensional Cognitive System

    ERIC Educational Resources Information Center

    Kearsley, Greg P.; And Others

    1977-01-01

    Theoretical concepts from multivariate developmental psychology and systems theory are used to describe qualitative and quantitative change in three cognitive subsystems: perceiving, conceptualizing, and symbolizing. Available from: Ablex Publishing Corporation, 355 Chestnut Street, Norwood, New Jersey 07648. (CL)

  17. Age-Related Changes in the Functional Network Underlying Specific and General Autobiographical Memory Retrieval: A Pivotal Role for the Anterior Cingulate Cortex

    PubMed Central

    Martinelli, Pénélope; Sperduti, Marco; Devauchelle, Anne-Dominique; Kalenzaga, Sandrine; Gallarda, Thierry; Lion, Stéphanie; Delhommeau, Marion; Anssens, Adèle; Amado, Isabelle; Meder, Jean François; Krebs, Marie-Odile; Oppenheim, Catherine; Piolino, Pascale

    2013-01-01

    Age-related changes in autobiographical memory (AM) recall are characterized by a decline in episodic details, while semantic aspects are spared. This deleterious effect is supposed to be mediated by an inefficient recruitment of executive processes during AM retrieval. To date, contrasting evidence has been reported on the neural underpinning of this decline, and none of the previous studies has directly compared the episodic and semantic aspects of AM in elderly. We asked 20 young and 17 older participants to recall specific and general autobiographical events (i.e., episodic and semantic AM) elicited by personalized cues while recording their brain activity by means of fMRI. At the behavioral level, we confirmed that the richness of episodic AM retrieval is specifically impoverished in aging and that this decline is related to the reduction of executive functions. At the neural level, in both age groups, we showed the recruitment of a large network during episodic AM retrieval encompassing prefrontal, cortical midline and posterior regions, and medial temporal structures, including the hippocampus. This network was very similar, but less extended, during semantic AM retrieval. Nevertheless, a greater activity was evidenced in the dorsal anterior cingulate cortex (dACC) during episodic, compared to semantic AM retrieval in young participants, and a reversed pattern in the elderly. Moreover, activity in dACC during episodic AM retrieval was correlated with inhibition and richness of memories in both groups. Our findings shed light on the direct link between episodic AM retrieval, executive control, and their decline in aging, proposing a possible neuronal signature. They also suggest that increased activity in dACC during semantic AM retrieval in the elderly could be seen as a compensatory mechanism underpinning successful AM performance observed in aging. These results are discussed in the framework of recently proposed models of neural reorganization in aging

  18. Change of retinal pigment epithelial atrophy after anti-vascular endothelial growth factor treatment in exudative age-related macular degeneration

    PubMed Central

    Kim, Moosang; Kim, Eung Suk; Seo, Kyung Hoon; Yu, Seung-Young; Kwak, Hyung-Woo

    2016-01-01

    Purpose: The study aimed to investigate the quantitative changes of retinal pigment epithelial (RPE) atrophy during a 24-month follow-up period of anti-vascular endothelial growth factor (VEGF) for exudative age-related macular degeneration (AMD). Materials and Methods: This is a retrospective study. Sixty-five eyes of 62 consecutive patients with naïve exudative AMD who had received treatment with anti-VEGF therapy and followed for more 24 months were enrolled. All patients received three initial monthly injections of anti-VEGF (ranibizumab or bevacizumab), followed by pro re nata or treat-and-extend protocol. Color fundus image, optical coherence tomography, and fundus autofluorescence were evaluated for RPE atrophy. Multiple regression analysis was performed to investigate the predictive factors found during univariate analysis to identify an association with increased RPE atrophic areas. Results: The mean number of anti-VEGF treatments was 9.18. RPE atrophic area was 1.293 ± 1.298 mm2 at baseline and enlarged to 2.394 ± 1.940 mm2 after 24 months, which differed significantly (P = 0.001). Multiple regression analysis revealed that larger areas of RPE atrophy at month 4 and larger numbers of anti-VEGF treatments were associated with increased RPE atrophic areas. Conclusions: RPE atrophy progresses in eyes with exudative AMD during anti-VEGF treatment. Larger areas of RPE atrophy at month 4 and larger numbers of anti-VEGF injections were associated with an increased risk of progression of RPE atrophy the following treatment. These findings may be useful to clinicians using intravitreal anti-VEGF for the treatment of exudative AMD, both for selecting an appropriate treatment plan and for predicting the progression of RPE atrophy. PMID:27488150

  19. Age-related changes in thirst, salt appetite, and arterial blood pressure in response to aldosterone-dexamethasone combination in rats

    PubMed Central

    Xue, Baojian; Beltz, Terry G.; Johnson, Alan Kim

    2015-01-01

    This work examined the effects of age on daily water and sodium ingestion and cardiovascular responses to chronic administration of the mineralocorticoid, aldosterone (ALDO) either alone or together with the glucocorticoid, dexamethasone (DEX). Young (4 mo), adult (12 mo), and aged (30 mo) male Brown Norway rats were prepared for continuous telemetry recording of blood pressure (BP) and heart rate (HR). Baseline water and sodium (i.e., 0.3 M NaCl) intake, BP, and HR were established for 10 days. Then ALDO (60 μg/day sc) was infused alone, or together with DEX (2.5 or 20 μg/day sc), for another 10 days. Compared with baseline levels, ALDO stimulated comparable increases in daily saline intake at all ages. ALDO together with the higher dose of DEX (i.e., ALDO/DEX20) increased daily saline intake more than did ALDO, but less so in aged rats. Infusion of ALDO/DEX20 increased mean arterial pressure (MAP), and decreased HR, more than did infusion of ALDO. The changes in MAP in response to both treatments depended on age. For all ages, MAP and saline intake increased simultaneously during ALDO, while MAP always increased before saline intake did during ALDO/DEX20. Contrary to our predictions, MAP did not increase more in old rats in response to either treatment. We speculate that age-related declines in cardiovascular responses to glucocorticoids contributed to the attenuated increases in sodium intake in response to glucocorticoids that were observed in older animals. PMID:25833938

  20. Age-related changes in the distributions of depressive symptom items in the general population: a cross-sectional study using the exponential distribution model.

    PubMed

    Tomitaka, Shinichiro; Kawasaki, Yohei; Ide, Kazuki; Yamada, Hiroshi; Furukawa, Toshiaki A; Ono, Yutaka

    2016-01-01

    Background. Previous research has reported inconsistent evidence of the trajectory of depressive symptoms across the adult lifespan. We investigated how the distributions of each item score change with age and determined whether the trajectory of depressive symptoms varied with the scoring methods of the questionnaire. Methods. We analyzed data collected from 21,040 subjects who participated in the national survey in Japan. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale (CES-D). The CES-D has 20 items, each of which is scored in four grades of "rarely," "some," "much," and "most of the time." We used the exponential distribution model which fits the distributions of 16 negative symptom items of CES-D, with the probabilities of "some," "much," "most," and "rarely" expressed as P, Pr, Pr (2), and 1 - P × (r (2) + r + 1). Results. The distributions of the responses to 16 negative symptom items followed the common exponential model across all age groups. The mean of the estimated parameter r of 16 negative items showed a U-shape pattern, being high during 12-29 years, remaining low during 30-50 years, and then increasing again over 60 years. The trajectory of depressive symptom scores simulating the binary method was different from that of the empirical scores using the Likert method. Conclusions. Our findings show that the increase in the depressive symptoms score during older age is based on the increase of the parameter r. The differences in the scoring method may contribute to the different age-related patterns across the adult lifespan. PMID:26788427

  1. Nutritional interventions protect against age-related deficits in behavior: from animals to humans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aged rats show impaired performance on motor and cognitive tasks. Similar changes in behavior occur in humans with age, and the development of methods to retard or reverse these age-related neuronal and behavioral deficits could increase healthy aging and decrease health care costs. In the present s...

  2. Growth curves and age-related changes in carcass characteristics, organs, serum parameters, and intestinal transporter gene expression in domestic pigeon (Columba livia).

    PubMed

    Gao, C Q; Yang, J X; Chen, M X; Yan, H C; Wang, X Q

    2016-04-01

    Two experiments were conducted to fit growth curves, and determine age-related changes in ca