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Sample records for age related variations

  1. Tooth Size Variation Related to Age in Amboseli Baboons

    PubMed Central

    Galbany, Jordi; Dotras, Laia; Alberts, Susan C.; Pérez-Pérez, Alejandro

    2011-01-01

    We measured the molar size from a single population of wild baboons from Amboseli (Kenya), both females (n = 57) and males (n = 50). All the females were of known age; the males represented a mix of known-age individuals (n = 31) and individuals with ages estimated to within 2 years (n = 19). The results showed a significant reduction in the mesiodistal length of teeth in both sexes as a function of age. Overall patterns of age-related change in tooth size did not change whether we included or excluded the individuals of estimated age, but patterns of statistical significance changed as a result of changed sample sizes. Our results demonstrate that tooth length is directly related to age due to interproximal wearing caused by M2 and M3 compression loads. Dental studies in primates, including both fossil and extant species, are mostly based on specimens obtained from osteological collections of varying origins, for which the age at death of each individual in the sample is not known. Researchers should take into account the phenomenon of interproximal attrition leading to reduced tooth size when measuring tooth length for ondontometric purposes. PMID:21325862

  2. PETN: Variation in Physical and Chemical Characteristics Related to Aging.

    SciTech Connect

    Monroe, D. C.; Laintz, K. E.; Kramer, J. F.; Peterson, P. D.

    2006-01-01

    Physical and chemical analyses of five PETN (pentaerythritol tetranitrate) batches have been conducted to assist in defining powder acceptance criteria for qualification of newly manufactured powders, as well as for examination of potential changes related to aging and thus changes in performance. Results showed that (1) repeatable Fisher Sub-Sieve Sizer measurements (which relate well to historic performance data) could be obtained with consistent sample setup and measurement techniques; (2) BET nitrogen adsorption estimates of surface area correlate well with Fisher measurements and appear less variable; (3) PharmaVision particle size analyses show promise in discriminating among PETN batches; and (4) SEMs are extremely useful in semi-quantitative discrimination among batches. Physical and chemical data will be related to performance data (to be obtained) to develop quantitative physical and chemical tests useful in predicting performance over time, i.e., as powders age.

  3. Characterization of age-related variation in corneal biomechanical properties

    PubMed Central

    Elsheikh, Ahmed; Geraghty, Brendan; Rama, Paolo; Campanelli, Marino; Meek, Keith M.

    2010-01-01

    An experimental study has been conducted to determine the stress–strain behaviour of human corneal tissue and how the behaviour varies with age. Fifty-seven well-preserved ex vivo donor corneas aged between 30 and 99 years were subjected to cycles of posterior pressure up to 60 mm Hg while monitoring their behaviour. The corneas were mechanically clamped along their ring of scleral tissue and kept in physiological conditions of temperature and hydration. The tissue demonstrated hyper-elastic pressure-deformation and stress–strain behaviour that closely matched an exponential trend. Clear stiffening (increased resistance to deformation) with age was observed in all loading cycles, and the rate of stiffness growth was nonlinear with bias towards older specimens. With a strong statistical association between stiffness and age (p < 0.05), it was possible to develop generic stress–strain equations that were suitable for all ages between 30 and 99 years. These equations, which closely matched the experimental results, depicted corneal stiffening with age in a form suitable for implementation in numerical simulations of ocular biomechanical behaviour. PMID:20392712

  4. Age-Related and Heteroplasmy-Related Variation in Human mtDNA Copy Number

    PubMed Central

    Li, Mingkun; Madea, Burkhard; Stoneking, Mark

    2016-01-01

    The mitochondrial (mt) genome is present in many copies in human cells, and intra-individual variation in mtDNA sequences is known as heteroplasmy. Recent studies found that heteroplasmies are highly tissue-specific, site-specific, and allele-specific, however the functional implications have not been explored. This study investigates variation in mtDNA copy numbers (mtCN) in 12 different tissues obtained at autopsy from 152 individuals (ranging in age from 3 days to 96 years). Three different methods to estimate mtCN were compared: shotgun sequencing (in 4 tissues), capture-enriched sequencing (in 12 tissues) and droplet digital PCR (ddPCR, in 2 tissues). The highest precision in mtCN estimation was achieved using shotgun sequencing data. However, capture-enrichment data provide reliable estimates of relative (albeit not absolute) mtCNs. Comparisons of mtCN from different tissues of the same individual revealed that mtCNs in different tissues are, with few exceptions, uncorrelated. Hence, each tissue of an individual seems to regulate mtCN in a tissue-related rather than an individual-dependent manner. Skeletal muscle (SM) samples showed an age-related decrease in mtCN that was especially pronounced in males, while there was an age-related increase in mtCN for liver (LIV) samples. MtCN in SM samples was significantly negatively correlated with both the total number of heteroplasmic sites and with minor allele frequency (MAF) at two heteroplasmic sites, 408 and 16327. Heteroplasmies at both sites are highly specific for SM, accumulate with aging and are part of functional elements that regulate mtDNA replication. These data support the hypothesis that selection acting on these heteroplasmic sites is reducing mtCN in SM of older individuals. PMID:26978189

  5. Heterogeneity of variation of relative risk by age at exposure in the Japanese atomic bomb survivors.

    PubMed

    Little, Mark P

    2009-08-01

    General reductions in cancer relative risk with increasing age at exposure are observed in the Japanese atomic bomb survivors and in other groups. However, there has been little evidence of heterogeneity in such trends by cancer type within the Japanese cohort, nor for cancer-type variations in other factors (sex, attained age) that modify relative risk. A recent report on the Japanese atomic bomb survivors published by Preston et al. in 2007 suggests that solid cancer relative risk exhibits a U-shaped relationship with age at exposure, and is initially decreasing and then increasing at older exposure ages. In this report, we reanalyse the latest Japanese atomic bomb survivor solid cancer mortality and incidence data analysed by Preston and co-workers, stratifying by cancer subtype where possible, the stratification being both in relation to the baseline and the radiation-associated excess. We find highly statistically significant (P < 0.001) variations of relative risk by cancer type, and statistically significant variations by cancer type in the adjustments for sex (P = 0.010) and age at exposure (P = 0.013) to the relative risk. There is no statistically significant (P > 0.2) variation by cancer type in the adjustment of relative risk for attained age. Although, for all incident solid cancers, there is marginally statistically significant (P = 0.033) variation of relative risk with a quadratic log-linear function of age at exposure, there is much weaker variation in the relative risk of solid cancer mortality (P > 0.1). However, the manner in which relative risk varies with age at exposure is qualitatively similar for incidence and mortality, so one should not make too much of these differences between the two datasets. Stratification by solid cancer type slightly weakens the evidence for quadratic variation in relative risk by age at exposure (P = 0.060). PMID:19471953

  6. Multiple Brain Markers are Linked to Age-Related Variation in Cognition.

    PubMed

    Hedden, Trey; Schultz, Aaron P; Rieckmann, Anna; Mormino, Elizabeth C; Johnson, Keith A; Sperling, Reisa A; Buckner, Randy L

    2016-04-01

    Age-related alterations in brain structure and function have been challenging to link to cognition due to potential overlapping influences of multiple neurobiological cascades. We examined multiple brain markers associated with age-related variation in cognition. Clinically normal older humans aged 65-90 from the Harvard Aging Brain Study (N = 186) were characterized on a priori magnetic resonance imaging markers of gray matter thickness and volume, white matter hyperintensities, fractional anisotropy (FA), resting-state functional connectivity, positron emission tomography markers of glucose metabolism and amyloid burden, and cognitive factors of processing speed, executive function, and episodic memory. Partial correlation and mediation analyses estimated age-related variance in cognition shared with individual brain markers and unique to each marker. The largest relationships linked FA and striatum volume to processing speed and executive function, and hippocampal volume to episodic memory. Of the age-related variance in cognition, 70-80% was accounted for by combining all brain markers (but only ∼20% of total variance). Age had significant indirect effects on cognition via brain markers, with significant markers varying across cognitive domains. These results suggest that most age-related variation in cognition is shared among multiple brain markers, but potential specificity between some brain markers and cognitive domains motivates additional study of age-related markers of neural health. PMID:25316342

  7. A reexamination of age-related variation in body weight and morphometry of Maryland nutria

    USGS Publications Warehouse

    Sherfy, M.H.; Mollett, T.A.; McGowan, K.R.; Daugherty, S.L.

    2006-01-01

    Age-related variation in morphometry has been documented for many species. Knowledge of growth patterns can be useful for modeling energetics, detecting physiological influences on populations, and predicting age. These benefits have shown value in understanding population dynamics of invasive species, particularly in developing efficient control and eradication programs. However, development and evaluation of descriptive and predictive models is a critical initial step in this process. Accordingly, we used data from necropsies of 1,544 nutria (Myocastor coypus) collected in Maryland, USA, to evaluate the accuracy of previously published models for prediction of nutria age from body weight. Published models underestimated body weights of our animals, especially for ages <3. We used cross-validation procedures to develop and evaluate models for describing nutria growth patterns and for predicting nutria age. We derived models from a randomly selected model-building data set (n = 192-193 M, 217-222 F) and evaluated them with the remaining animals (n = 487-488 M, 642-647 F). We used nonlinear regression to develop Gompertz growth-curve models relating morphometric variables to age. Predicted values of morphometric variables fell within the 95% confidence limits of their true values for most age classes. We also developed predictive models for estimating nutria age from morphometry, using linear regression of log-transformed age on morphometric variables. The evaluation data set corresponded with 95% prediction intervals from the new models. Predictive models for body weight and length provided greater accuracy and less bias than models for foot length and axillary girth. Our growth models accurately described age-related variation in nutria morphometry, and our predictive models provided accurate estimates of ages from morphometry that will be useful for live-captured individuals. Our models offer better accuracy and precision than previously published models

  8. The eye lens: age-related trends and individual variations in refractive index and shape parameters.

    PubMed

    Pierscionek, Barbara; Bahrami, Mehdi; Hoshino, Masato; Uesugi, Kentaro; Regini, Justyn; Yagi, Naoto

    2015-10-13

    The eye lens grows throughout life by cell accrual on its surface and can change shape to adjust the focussing power of the eye. Varying concentrations of proteins in successive cell layers create a refractive index gradient. The continued growth of the lens and age-related changes in proteins render it less able to alter shape with loss of capacity by the end of the sixth decade of life. Growth and protein ageing alter the refractive index but as accurate measurement of this parameter is difficult, the nature of such alterations remains uncertain. The most accurate method to date for measuring refractive index in intact lenses has been developed at the SPring-8 synchrotron. The technique, based on Talbot interferometry, has an X-ray source and was used to measure refractive index in sixty-six human lenses, aged from 16 to 91 years. Height and width were measured for forty-five lenses. Refractive index contours show decentration in some older lenses but individual variations mask age-related trends. Refractive index profiles along the optic axis have relatively flat central sections with distinct micro-fluctuations and a steep gradient in the cortex but do not exhibit an age-related trend. The refractive index profiles in the equatorial aspect show statistical significance with age, particularly for lenses below the age of sixty that had capacity to alter shape in vivo. The maximum refractive index in the lens centre decreases slightly with age with considerable scatter in the data and there are age-related variations in sagittal thickness and equatorial height. PMID:26416418

  9. The eye lens: age-related trends and individual variations in refractive index and shape parameters

    PubMed Central

    Pierscionek, Barbara; Bahrami, Mehdi; Hoshino, Masato; Uesugi, Kentaro; Regini, Justyn; Yagi, Naoto

    2015-01-01

    The eye lens grows throughout life by cell accrual on its surface and can change shape to adjust the focussing power of the eye. Varying concentrations of proteins in successive cell layers create a refractive index gradient. The continued growth of the lens and age-related changes in proteins render it less able to alter shape with loss of capacity by the end of the sixth decade of life. Growth and protein ageing alter the refractive index but as accurate measurement of this parameter is difficult, the nature of such alterations remains uncertain. The most accurate method to date for measuring refractive index in intact lenses has been developed at the SPring-8 synchrotron. The technique, based on Talbot interferometry, has an X-ray source and was used to measure refractive index in sixty-six human lenses, aged from 16 to 91 years. Height and width were measured for forty-five lenses. Refractive index contours show decentration in some older lenses but individual variations mask age-related trends. Refractive index profiles along the optic axis have relatively flat central sections with distinct micro-fluctuations and a steep gradient in the cortex but do not exhibit an age-related trend. The refractive index profiles in the equatorial aspect show statistical significance with age, particularly for lenses below the age of sixty that had capacity to alter shape in vivo. The maximum refractive index in the lens centre decreases slightly with age with considerable scatter in the data and there are age-related variations in sagittal thickness and equatorial height. PMID:26416418

  10. Spatial variation in osteonal bone properties relative to tissue and animal age.

    PubMed

    Gourion-Arsiquaud, Samuel; Burket, Jayme C; Havill, Lorena M; DiCarlo, Edward; Doty, Stephen B; Mendelsohn, Richard; van der Meulen, Marjolein C H; Boskey, Adele L

    2009-07-01

    Little is known about osteonal bone mineral and matrix properties, although these properties are of major importance for the understanding of bone alterations related to age and bone diseases such as osteoporosis. During aging, bone undergoes modifications that compromise their structural integrity as shown clinically by the increase of fracture incidence with age. Based on Fourier transform infrared (FTIR) analysis from baboons between 0 and 32 yr of age, consistent systematic variations in bone properties as a function of tissue age are reported within osteons. The patterns observed were independent of animal age and positively correlated with bone tissue elastic behavior measured by nano-indentation. As long as tissue age is expressed as a percentage of the entire osteon radius, osteonal analyses can be used to characterize disease changes independent of the size of the osteon. These mineral and matrix analyses can be used to explain bone fragility. The mineral content (mineral-to-matrix ratio) was correlated with the animal age in both old (interstitial) and newly formed bone tissue, showing for the first time that age-related changes in BMC can be explain by an alteration in the mineralization process itself and not only by an imbalance in the remodeling process. PMID:19210217

  11. Serum osteocalcin in dairy cows: age-related changes and periparturient variation.

    PubMed

    Sato, Reiichiro; Onda, Ken; Ochiai, Hideharu; Iriki, Tsunenori; Yamazaki, Yukio; Wada, Yasunori

    2011-10-01

    We evaluated age-related changes in serum osteocalcin concentrations in non-periparturient cows and variations in serum osteocalcin concentration in periparturient primiparous and multiparous cows. The serum osteocalcin levels were evaluated in 144 non-periparturient Holstein dairy cows aged 11 days to 10 years; these levels were the highest in the youngest cows, appeared to steadily decrease with age until the time of the first calving, and were subsequently maintained at low levels. Between 14 days before calving and 21 days after calving, the serum osteocalcin levels were significantly higher in the primiparous cows than in the multiparous cows. A comparison between age-matched non-periparturient and periparturient cows showed that serum osteocalcin levels were significantly lowered during late gestation in both primiparous and multiparous cows. These results suggest that serum osteocalcin measurement might be useful for the detection of mineral imbalances at the time of parturition in cows. PMID:21300389

  12. Sex- and age-related variations of the somatotype in a Chuvasha population.

    PubMed

    Kalichman, L; Kobyliansky, E

    2006-01-01

    The aim of this large, cross-sectional study was to describe the age- and sex-related variations of the somatotype, employing Heath and Carter's method, in a Chuvasha population residing in a rural region in central Russia. The investigated sample included 802 males aged 18-89 years (mean 46.9) and 738 females aged 18-90 years (mean 48.6). We evaluated the age and sex differences by one-way ANOVA with somatotype components as dependent variables and sex or age groups as grouping variables. Sex differences of somatotypes appear to be the strongest for endomorphy, with generally higher values in women. Endomorphy in males remained virtually unchanged after 30 years of age, but endomorphy in females kept increasing up to the 6th decade, and then subsequently decreased. Virtually no differences were noted in mesomorphy and a very small difference in ectomorphy between males and females aged 18-30 years. A reduction of sexual dimorphism in all somatotype components after age 70 was also observed. The largest difference of all somatotype components appeared between age groups 18-30 and 31-40 years. Thereafter, somatotypes remained practically unchanged. Mesomorphy continued to increase until the 5th decade in both sexes, while in females, endomorphy continuously increased until their 6th decade. In the 7th and 8th decades, a decrease in mean values was observed. Mesomorphy and ectomorphy showed opposite age-related trends. Results of our study clearly suggest that in physique investigations, the somatotypes need to be studied in each sex separately, and in studies of young people, they need also to be adjusted to age. PMID:16574118

  13. Variation of the Anthropometric Index for pectus excavatum relative to age, race, and sex

    PubMed Central

    Rebeis, Eduardo Baldassari; de Campos, Jose Ribas Milanez; Moreira, Luis Felipe Pinho; Pastorino, Antonio Carlos; Pêgo-Fernandes, Paulo Manuel; Jatene, Fabio Biscegli

    2013-01-01

    OBJECTIVES: To determine possible variations in the Anthropometric Index for pectus excavatum relative to age, race, and sex in individuals free of thoracic wall deformities. METHODS: Between 2002 and 2012, 166 individuals with morphologically normal thoracic walls consented to have their chests and the perimeter of the lower third of the thorax measured according to the Anthropometric Index for pectus excavatum. The participant characteristics are presented (114 men and 52 women; 118 Caucasians and 48 people of African descent). RESULTS: Measurements of the Anthropometric Index for pectus excavatum were statistically significantly different between men and women (11–40 years old); however, no significant difference was found between Caucasians and people of African descent. For men, the index measurements were not significantly different across all of the age groups. For women, the index measurements were significantly lower for individuals aged 3 to 10 years old than for individuals aged 11 to 20 years old and 21 to 40 years old; however, no such difference was observed between women aged 11 to 20 years old and those aged 21 to 40 years old. CONCLUSION: In the sample, significant differences were observed between women aged 11 to 40 years old and the other age groups; however, there was no difference between Caucasian and people of African descent. PMID:24141837

  14. MITOCHONDRIAL VARIATION AND THE RISK OF AGE-RELATED MACULAR DEGENERATION ACROSS DIVERSE POPULATIONS

    PubMed Central

    RESTREPO, NICOLE A.; MITCHELL, SABRINA L.; GOODLOE, ROBERT J.; MURDOCK, DEBORAH G.; HAINES, JONANTHAN L.; CRAWFORD, DANA C.

    2014-01-01

    Substantial progress has been made in identifying susceptibility variants for age-related macular degeneration (AMD). The majority of research to identify genetic variants associated with AMD has focused on nuclear genetic variation. While there is some evidence that mitochondrial genetic variation contributes to AMD susceptibility, to date, these studies have been limited to populations of European descent resulting in a lack of data in diverse populations. A major goal of the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) study is to describe the underlying genetic architecture of common, complex diseases across diverse populations. This present study sought to determine if mitochondrial genetic variation influences risk of AMD across diverse populations. We performed a genetic association study to investigate the contribution of mitochondrial DNA variation to AMD risk. We accessed samples from the National Health and Nutrition Examination Surveys, a U.S population-based, cross-sectional survey collected without regard to health status. AMD cases and controls were selected from the Third NHANES and NHANES 2007-2008 datasets which include non-Hispanic whites, non-Hispanic blacks, and Mexican Americans. AMD cases were defined as those > 60 years of age with early/late AMD, as determined by fundus photography. Targeted genotyping was performed for 63 mitochondrial SNPs and participants were then classified into mitochondrial haplogroups. We used logistic regression assuming a dominant genetic model adjusting for age, sex, body mass index, and smoking status (ever vs. never). Regressions and meta-analyses were performed for individual SNPs and mitochondrial haplogroups J, T, and U. We identified five SNPs associated with AMD in Mexican Americans at p < 0.05, including three located in the control region (mt16111, mt16362, and mt16319), one in MT-RNR2 (mt1736), and one in MT-ND4 (mt12007). No mitochondrial variant or haplogroup was significantly

  15. Age-related variation in EEG complexity to photic stimulation: A multiscale entropy analysis

    PubMed Central

    Takahashi, Tetsuya; Cho, Raymond Y.; Murata, Tetsuhito; Mizuno, Tomoyuki; Kikuchi, Mitsuru; Mizukami, Kimiko; Kosaka, Hirotaka; Takahashi, Koichi; Wada, Yuji

    2010-01-01

    Objective This study was intended to examine variations in electroencephalographic (EEG) complexity in response to photic stimulation (PS) during aging to test the hypothesis that the aging process reduces physiologic complexity and functional responsiveness. Methods Multiscale entropy (MSE), an estimate of time-series signal complexity associated with long-range temporal correlation, is used as a recently proposed method for quantifying EEG complexity with multiple coarse-grained sequences. We recorded EEG in 13 healthy elderly subjects and 12 healthy young subjects during pre-PS and post-PS conditions and estimated their respective MSE values. Results For the pre-PS condition, no significant complexity difference was found between the groups. However, a significant MSE change (complexity increase) was found post-PS only in young subjects, thereby revealing a power-law scaling property, which means long-range temporal correlation. Conclusions Enhancement of long-range temporal correlation in young subjects after PS might reflect a cortical response to stimuli, which was absent in elderly subjects. These results are consistent with the general “loss of complexity/diminished functional response to stimuli” theory of aging. Significance Our findings demonstrate that application of MSE analysis to EEG is a powerful approach for studying age-related changes in brain function. PMID:19231279

  16. Variation among individuals in photoperiod responses: Effects of breeding schedule, photoperiod, and age-related photoperiodic experience in birds.

    PubMed

    Watts, Heather E; MacDougall-Shackleton, Scott A; Hahn, Thomas P

    2015-07-01

    Many organisms use environmental cues to regulate reproductive function in order to time reproduction to coincide with favorable environmental conditions. Whereas we understand much about how environmental cues are used to time reproduction, we know relatively little about variation among individuals in responsiveness to environmental cues. However, this variation among individuals may represent a crucial component of a population's capacity to respond to changing environmental conditions. In this study, we quantify variation among individuals in photoperiod responsiveness of the avian reproductive system and investigate three potential underlying sources of this variation in environmental cue responsiveness. Specifically, we tested whether age-related photoperiodic experience, strength of the photoperiodic cue (day length), and degree of flexibility in breeding schedule influenced the degree of variation observed in experimental studies of seven species of cardueline finches. Overall, we found a high degree of variation among individuals in photoperiod response, and this was influenced by experimental photoperiod and breeding schedule. As experimental photoperiod became longer, the degree of variation declined. Opportunistic breeders showed greater variation in response compared with more seasonal breeders. We found no effect of age-related photoperiodic experience in one species for which we could examine this factor. The results of this study highlight the extent to which individuals can vary in their response to environmental cues and point to both species ecology and characteristics of the cue as important influences on the degree of this variation. PMID:25865942

  17. Age-related variation in foraging behaviour in the wandering albatross at South Georgia: no evidence for senescence.

    PubMed

    Froy, Hannah; Lewis, Sue; Catry, Paulo; Bishop, Charles M; Forster, Isaac P; Fukuda, Akira; Higuchi, Hiroyoshi; Phalan, Ben; Xavier, Jose C; Nussey, Daniel H; Phillips, Richard A

    2015-01-01

    Age-related variation in demographic rates is now widely documented in wild vertebrate systems, and has significant consequences for population and evolutionary dynamics. However, the mechanisms underpinning such variation, particularly in later life, are less well understood. Foraging efficiency is a key determinant of fitness, with implications for individual life history trade-offs. A variety of faculties known to decline in old age, such as muscular function and visual acuity, are likely to influence foraging performance. We examine age-related variation in the foraging behaviour of a long-lived, wide-ranging oceanic seabird, the wandering albatross Diomedea exulans. Using miniaturised tracking technologies, we compared foraging trip characteristics of birds breeding at Bird Island, South Georgia. Based on movement and immersion data collected during the incubation phase of a single breeding season, and from extensive tracking data collected in previous years from different stages of the breeding cycle, we found limited evidence for age-related variation in commonly reported trip parameters, and failed to detect signs of senescent decline. Our results contrast with the limited number of past studies that have examined foraging behaviour in later life, since these have documented changes in performance consistent with senescence. This highlights the importance of studies across different wild animal populations to gain a broader perspective on the processes driving variation in ageing rates. PMID:25574995

  18. Age-Related Variation in Foraging Behaviour in the Wandering Albatross at South Georgia: No Evidence for Senescence

    PubMed Central

    Froy, Hannah; Lewis, Sue; Catry, Paulo; Bishop, Charles M.; Forster, Isaac P.; Fukuda, Akira; Higuchi, Hiroyoshi; Phalan, Ben; Xavier, Jose C.; Nussey, Daniel H.; Phillips, Richard A.

    2015-01-01

    Age-related variation in demographic rates is now widely documented in wild vertebrate systems, and has significant consequences for population and evolutionary dynamics. However, the mechanisms underpinning such variation, particularly in later life, are less well understood. Foraging efficiency is a key determinant of fitness, with implications for individual life history trade-offs. A variety of faculties known to decline in old age, such as muscular function and visual acuity, are likely to influence foraging performance. We examine age-related variation in the foraging behaviour of a long-lived, wide-ranging oceanic seabird, the wandering albatross Diomedea exulans. Using miniaturised tracking technologies, we compared foraging trip characteristics of birds breeding at Bird Island, South Georgia. Based on movement and immersion data collected during the incubation phase of a single breeding season, and from extensive tracking data collected in previous years from different stages of the breeding cycle, we found limited evidence for age-related variation in commonly reported trip parameters, and failed to detect signs of senescent decline. Our results contrast with the limited number of past studies that have examined foraging behaviour in later life, since these have documented changes in performance consistent with senescence. This highlights the importance of studies across different wild animal populations to gain a broader perspective on the processes driving variation in ageing rates. PMID:25574995

  19. Variations in Students' School- and Teacher-Related Attitudes across Gender, Ethnicity, and Age

    ERIC Educational Resources Information Center

    Sullivan, Jeremy R.; Riccio, Cynthia A.; Reynolds, Cecil R.

    2008-01-01

    The present study examined differences across gender, ethnicity, and age with regard to the nature of participants' self-reported attitudes toward school and teachers, based on previous research suggesting that students' school- and teacher-related attitudes appear to have an influence on academic achievement. This study employed an archival…

  20. Age-related variation in reproductive traits in the wandering albatross: evidence for terminal improvement following senescence.

    PubMed

    Froy, Hannah; Phillips, Richard A; Wood, Andrew G; Nussey, Daniel H; Lewis, Sue

    2013-05-01

    The processes driving age-related variation in demographic rates are central to understanding population and evolutionary ecology. An increasing number of studies in wild vertebrates find evidence for improvements in reproductive performance traits in early adulthood, followed by senescent declines in later life. However, life history theory predicts that reproductive investment should increase with age as future survival prospects diminish, and that raised reproductive investment may have associated survival costs. These non-mutually exclusive processes both predict an increase in breeding performance at the terminal breeding attempt. Here, we use a 30-year study of wandering albatrosses (Diomedea exulans) to disentangle the processes underpinning age-related variation in reproduction. Whilst highlighting the importance of breeding experience, we reveal senescent declines in performance are followed by a striking increase in breeding success and a key parental investment trait at the final breeding attempt. PMID:23438213

  1. Sex- and age-related variation in metal content of penguin feathers.

    PubMed

    Squadrone, Stefania; Abete, Maria Cesarina; Brizio, Paola; Monaco, Gabriella; Colussi, Silvia; Biolatti, Cristina; Modesto, Paola; Acutis, Pier Luigi; Pessani, Daniela; Favaro, Livio

    2016-03-01

    The presence of xenobiotics, such as metals, in ecosystems is concerning due to their durability and they pose a threat to the health and life of organisms. Moreover, mercury can biomagnify in many marine food chains and, therefore, organisms at higher trophic levels can be adversely impacted. Although feathers have been used extensively as a bio-monitoring tool, only a few studies have addressed the effect of both age and sex on metal accumulation. In this study, the concentrations of trace elements were determined in the feathers of all members of a captive colony of African Penguins (Spheniscus demersus) housed in a zoological facility in Italy. Tests were performed by inductively coupled plasma-mass spectrometry to detect aluminum, arsenic, cadmium, cobalt, chromium, copper, iron, manganese, nickel, lead, selenium, tin, vanadium, and zinc. Mercury was detected by a direct mercury analyzer. Sexing was performed by a molecular approach based on analyzing the chromo-helicase-DNA-binding1 gene, located on the sex chromosomes. Sex- and age-related differences were studied in order to investigate the different patterns of metal bioaccumulation between male and female individuals and between adults and juveniles. Juvenile females had significantly higher arsenic levels than males, while selenium levels increased significantly with age in both sexes. Penguins kept in controlled environments-given that diet and habitat are under strict control-represent a unique opportunity to determine if and how metal bioaccumulation is related to sex and age. PMID:26597735

  2. Variations in relative age effects in individual sports: skiing, figure skating and gymnastics.

    PubMed

    Baker, Joseph; Janning, Christina; Wong, Harmonie; Cobley, Stephen; Schorer, Jörg

    2014-01-01

    In many sports, policy-makers and administrators employ annual cohorts to reduce differences between athletes during childhood and youth. Although well-intended, unintended relative age effects (RAEs) usually occur. RAEs refer to the specific selection, participation and attainment disadvantages associated with participants' birthdates relative to an arbitrary 'cutoff' date used to group participants within annual age groups. To date, we have little understanding of RAEs in individual sports. In this article, Study 1 considered the presence of RAEs in 1474 ski jumping, 7501 cross-country skiing, 15,565 alpine skiing, 4179 snowboarders and 713 Nordic combined athletes. Chi-square analyses revealed significant RAEs for most of these contexts across sexes. In Study 2, RAEs in the aesthetic sports of figure skating (n=502) and female gymnastics (n=612) were considered. There was no effect for the figure skaters and an atypical effect for the gymnasts. The significant effects across most ski sports coupled with the null effects in figure skating and atypical effect in gymnastics suggest that sport-specific contextual factors are important elements in understanding the mechanisms of RAEs, although further work is necessary to validate these findings. PMID:24444205

  3. No Association between Variation in Longevity Candidate Genes and Aging-related Phenotypes in Oldest-old Danes.

    PubMed

    Soerensen, Mette; Nygaard, Marianne; Debrabant, Birgit; Mengel-From, Jonas; Dato, Serena; Thinggaard, Mikael; Christensen, Kaare; Christiansen, Lene

    2016-06-01

    In this study we explored the association between aging-related phenotypes previously reported to predict survival in old age and variation in 77 genes from the DNA repair pathway, 32 genes from the growth hormone 1/ insulin-like growth factor 1/insulin (GH/IGF-1/INS) signalling pathway and 16 additional genes repeatedly considered as candidates for human longevity: APOE, APOA4, APOC3, ACE, CETP, HFE, IL6, IL6R, MTHFR, TGFB1, SIRTs 1, 3, 6; and HSPAs 1A, 1L, 14. Altogether, 1,049 single nucleotide polymorphisms (SNPs) were genotyped in 1,088 oldest-old (age 92-93 years) Danes and analysed with phenotype data on physical functioning (hand grip strength), cognitive functioning (mini mental state examination and a cognitive composite score), activity of daily living and self-rated health. Five SNPs showed association to one of the phenotypes; however, none of these SNPs were associated with a change in the relevant phenotype over time (7 years of follow-up) and none of the SNPs could be confirmed in a replication sample of 1,281 oldest-old Danes (age 94-100). Hence, our study does not support association between common variation in the investigated longevity candidate genes and aging-related phenotypes consistently shown to predict survival. It is possible that larger sample sizes are needed to robustly reveal associations with small effect sizes. PMID:26946122

  4. Age- and sex-related variations in vocal-tract morphology and voice acoustics during adolescence.

    PubMed

    Markova, Diana; Richer, Louis; Pangelinan, Melissa; Schwartz, Deborah H; Leonard, Gabriel; Perron, Michel; Pike, G Bruce; Veillette, Suzanne; Chakravarty, M Mallar; Pausova, Zdenka; Paus, Tomáš

    2016-05-01

    Distinct differences in the human voice emerge during adolescence, with males producing deeper and more resonant voices than females by the end of sexual maturation. Using magnetic resonance images of heads and voice recordings obtained in 532 typically developing adolescents, we investigate what might be the drivers of this change in voice, and the subjective judgment of the voice "maleness" and "femaleness". We show clear sex differences in the morphology of voice-related structures during adolescence, with males displaying strong associations between age (and puberty) and both vocal-fold and vocal-tract length; this was not the case in female adolescents. At the same time, males (compared with females) display stronger associations between age (and puberty) with both fundamental frequency and formant position. In males, vocal morphology was a mediator in the relationship between bioavailable testosterone and acoustic indices. Subjective judgment of the voice sex could be predicted by the morphological and acoustic parameters in males only: the length of vocal folds and its acoustic counterpart, fundamental frequency, is a larger predictor of subjective "maleness" of a voice than vocal-tract length and formant position. PMID:27062936

  5. Age-Related Variation in Health Service Use and Associated Expenditures among Children with Autism

    ERIC Educational Resources Information Center

    Cidav, Zuleyha; Lawer, Lindsay; Marcus, Steven C.; Mandell, David S.

    2013-01-01

    This study examined differences by age in service use and associated expenditures during 2005 for Medicaid-enrolled children with autism spectrum disorders. Aging was associated with significantly higher use and costs for restrictive, institution-based care and lower use and costs for community-based therapeutic services. Total expenditures…

  6. Better stay together: pair bond duration increases individual fitness independent of age-related variation.

    PubMed

    Sánchez-Macouzet, Oscar; Rodríguez, Cristina; Drummond, Hugh

    2014-07-01

    Prolonged pair bonds have the potential to improve reproductive performance of socially monogamous animals by increasing pair familiarity and enhancing coordination and cooperation between pair members. However, this has proved very difficult to test robustly because of important confounds such as age and reproductive experience. Here, we address limitations of previous studies and provide a rigorous test of the mate familiarity effect in the socially monogamous blue-footed booby, Sula nebouxii, a long-lived marine bird with a high divorce rate. Taking advantage of a natural disassociation between age and pair bond duration in this species, and applying a novel analytical approach to a 24 year database, we found that those pairs which have been together for longer establish their clutches five weeks earlier in the season, hatch more of their eggs and produce 35% more fledglings, regardless of age and reproductive experience. Our results demonstrate that pair bond duration increases individual fitness and further suggest that synergistic effects between a male and female's behaviour are likely to be involved in generating a mate familiarity effect. These findings help to explain the age- and experience-independent benefits of remating and their role in life-history evolution. PMID:24827435

  7. Better stay together: pair bond duration increases individual fitness independent of age-related variation

    PubMed Central

    Sánchez-Macouzet, Oscar; Rodríguez, Cristina; Drummond, Hugh

    2014-01-01

    Prolonged pair bonds have the potential to improve reproductive performance of socially monogamous animals by increasing pair familiarity and enhancing coordination and cooperation between pair members. However, this has proved very difficult to test robustly because of important confounds such as age and reproductive experience. Here, we address limitations of previous studies and provide a rigorous test of the mate familiarity effect in the socially monogamous blue-footed booby, Sula nebouxii, a long-lived marine bird with a high divorce rate. Taking advantage of a natural disassociation between age and pair bond duration in this species, and applying a novel analytical approach to a 24 year database, we found that those pairs which have been together for longer establish their clutches five weeks earlier in the season, hatch more of their eggs and produce 35% more fledglings, regardless of age and reproductive experience. Our results demonstrate that pair bond duration increases individual fitness and further suggest that synergistic effects between a male and female's behaviour are likely to be involved in generating a mate familiarity effect. These findings help to explain the age- and experience-independent benefits of remating and their role in life-history evolution. PMID:24827435

  8. Metabonomic investigations of age- and batch-related variations in female NMRI mice using proton nuclear magnetic resonance spectroscopy.

    PubMed

    Li, Jia V; Saric, Jasmina; Yap, Ivan K S; Utzinger, Jürg; Holmes, Elaine

    2013-12-01

    The NMRI outbred mouse model is widely used for studying metabolic disease, toxicity, and infection, yet information regarding baseline metabolism of this murine strain is relatively sparse. Using different batches of female NMRI mice, we assessed the stability of the metabolic phenotype with increasing age and weight, and determined the influence of acclimatization on the metabolic profile of biofluids (urine, plasma, and faecal water). Differences in urinary concentrations of 3-ureidopropionate, 2-oxoisocaproate, trimethylamine, and glycine were detected between three batches of 9-week-old female NMRI mice using proton nuclear magnetic resonance ((1)H NMR) spectroscopy coupled with multivariate statistical analysis. An acclimatization period of 2 weeks was imposed after the mice entered the laboratory environment. Strong differences in the faecal metabolome pre- and post-acclimatization were found (reduction in amino acid concentrations), whilst the urine metabolome showed increased levels of trimethylamine-N-oxide, phenylacetyl glycine, and hippurate with decreased excretion of formate and betaine post-acclimatization. Temporal variation in the metabolite profiles over a 16-week study stabilized around 7-week-old animals. The results from this study strongly argue for inclusion of an acclimatization period prior to starting an investigative procedure, and suggest that the metabolic phenotypes of female NMRI mice are more stable at around 7 weeks of age. We have also identified a set of metabolites that are more susceptible to variation in concentration. This information can serve as a benchmark in order to establish confidence in systematic variation attributable to pathology or therapeutic intervention above the background metabolic variation in the NMRI mouse. PMID:24121299

  9. Dialysable and non-dialysable hydroxyproline in the rat's urine: age related and diurnal variations

    PubMed Central

    Gaggi, Renato; Gianni, Anna Maria; Montanaro, Nicola

    1982-01-01

    1. Urinary dialysable and non-dialysable hydroxyproline, which are considered good indices of bone resorption and neoformation respectively, were determined in rats under conditions that modify skeleton metabolism, such as body growth and parathyroid or calcitonin administration. It was also investigated whether dialysable and non-dialysable hydroxyproline excretions showed significant circadian fluctuations in rats of different ages. 2. Dialysable hydroxyproline excretion sharply decreased from the first to the fifth months of age and underwent further gradual reduction up to the fourteenth month of life. Non-dialysable hydroxyproline excretion followed a smoother decrease up to the fifth month, then remained constant. Urinary excretion of non-dialysable hydroxyproline expressed as a percentage of the total hydroxyprolinuria (n.d.%) slowly increased with advancing rat age. 3. In 2-, 4- and 6-month old rats, dialysable hydroxyproline excretion showed significant circadian fluctuations with minima and maxima at the end of the dark and light fraction of the cycle respectively. Daily fluctuations were greater in young and adult rats (50-65% of the respective average levels) than in 4-month old rats (25%). Non-dialysable hydroxyproline excretion followed similar but less pronounced patterns. Significant circadian fluctuations of n.d.% were detectable only in 2- and 4-month old rats, with peaks at 04.00-05.00 hr, thus indicating that the bone formation/resorption ratio increased in the nocturnal fraction of the cycle. 4. Young rats administered with calcitonin exhibited reduced levels of urinary dialysable but not of non-dialysable hydroxyproline when the hormone was given at 13.30 hr. No changes were observed when calcitonin was injected at 19.30 hr. On the contrary, both diurnal and nocturnal parathyroid hormone administration to young rats caused increased levels of dialysable and non-dialysable hydroxyproline of the same magnitude. PMID:7202048

  10. Individual, Contextual, and Age-Related Acoustic Variation in Simakobu (Simias concolor) Loud Calls

    PubMed Central

    Erb, Wendy M.; Hodges, J. Keith; Hammerschmidt, Kurt

    2013-01-01

    Primate loud calls have the potential to encode information about the identity, arousal, age, or physical condition of the caller, even at long distances. In this study, we conducted an analysis of the acoustic features of the loud calls produced by a species of Asian colobine monkey (simakobu, Simias concolor). Adult male simakobu produce loud calls spontaneously and in response to loud sounds and other loud calls, which are audible more than 500 m. Individual differences in calling rates and durations exist, but it is unknown what these differences signal and which other acoustic features vary among individuals. We aimed to describe the structure and usage of calls and to examine acoustic features that vary within and among individuals. We determined the context of 318 loud calls and analyzed 170 loud calls recorded from 10 adult males at an undisturbed site, Pungut, Siberut Island, Indonesia. Most calls (53%) followed the loud call of another male, 31% were spontaneous, and the remaining 16% followed a loud environmental disturbance. The fundamental frequency (F0) decreased while inter-unit intervals (IUI) increased over the course of loud call bouts, possibly indicating caller fatigue. Discriminant function analysis indicated that calls were not well discriminated by context, but spontaneous calls had higher peak frequencies, suggesting a higher level of arousal. Individual calls were distinct and individuals were mainly discriminated by IUI, call duration, and F0. Loud calls of older males had shorter IUI and lower F0, while middle-aged males had the highest peak frequencies. Overall, we found that calls were individually distinct and may provide information about the age, stamina, and arousal of the calling male, and could thus be a way for males and females to assess competitors and mates from long distances. PMID:24376651

  11. Femoral neck-shaft angle in humans: variation relating to climate, clothing, lifestyle, sex, age and side.

    PubMed

    Gilligan, Ian; Chandraphak, Supichya; Mahakkanukrauh, Pasuk

    2013-08-01

    The femoral neck-shaft angle (NSA) varies among modern humans but measurement problems and sampling limitations have precluded the identification of factors contributing to its variation at the population level. Potential sources of variation include sex, age, side (left or right), regional differences in body shape due to climatic adaptation, and the effects of habitual activity patterns (e.g. mobile and sedentary lifestyles and foraging, agricultural, and urban economies). In this study we addressed these issues, using consistent methods to assemble a global NSA database comprising over 8000 femora representing 100 human groups. Results from the analyses show an average NSA for modern humans of 127° (markedly lower than the accepted value of 135°); there is no sex difference, no age-related change in adults, but possibly a small lateral difference which could be due to right leg dominance. Climatic trends consistent with principles based on Bergmann's rule are evident at the global and continental levels, with the NSA varying in relation to other body shape indices: median NSA, for instance, is higher in warmer regions, notably in the Pacific (130°), whereas lower values (associated with a more stocky body build) are found in regions where ancestral populations were exposed to colder conditions, in Europe (126°) and the Americas (125°). There is a modest trend towards increasing NSA with the economic transitions from forager to agricultural and urban lifestyles and, to a lesser extent, from a mobile to a sedentary existence. However, the main trend associated with these transitions is a progressive narrowing in the range of variation in the NSA, which may be attributable to thermal insulation provided by improved cultural buffering from climate, particularly clothing. PMID:23781912

  12. Femoral neck-shaft angle in humans: variation relating to climate, clothing, lifestyle, sex, age and side

    PubMed Central

    Gilligan, Ian; Chandraphak, Supichya; Mahakkanukrauh, Pasuk

    2013-01-01

    The femoral neck-shaft angle (NSA) varies among modern humans but measurement problems and sampling limitations have precluded the identification of factors contributing to its variation at the population level. Potential sources of variation include sex, age, side (left or right), regional differences in body shape due to climatic adaptation, and the effects of habitual activity patterns (e.g. mobile and sedentary lifestyles and foraging, agricultural, and urban economies). In this study we addressed these issues, using consistent methods to assemble a global NSA database comprising over 8000 femora representing 100 human groups. Results from the analyses show an average NSA for modern humans of 127° (markedly lower than the accepted value of 135°); there is no sex difference, no age-related change in adults, but possibly a small lateral difference which could be due to right leg dominance. Climatic trends consistent with principles based on Bergmann's rule are evident at the global and continental levels, with the NSA varying in relation to other body shape indices: median NSA, for instance, is higher in warmer regions, notably in the Pacific (130°), whereas lower values (associated with a more stocky body build) are found in regions where ancestral populations were exposed to colder conditions, in Europe (126°) and the Americas (125°). There is a modest trend towards increasing NSA with the economic transitions from forager to agricultural and urban lifestyles and, to a lesser extent, from a mobile to a sedentary existence. However, the main trend associated with these transitions is a progressive narrowing in the range of variation in the NSA, which may be attributable to thermal insulation provided by improved cultural buffering from climate, particularly clothing. PMID:23781912

  13. Clinical and surgical implications regarding morphometric variations of the medial wall of the orbit in relation to age and gender.

    PubMed

    Morales-Avalos, Rodolfo; Santos-Martínez, Arlette Gabriela; Ávalos-Fernández, Cesia Gisela; Mohamed-Noriega, Karim; Sánchez-Mejorada, Gabriela; Montemayor-Alatorre, Adolfo; Martínez-Fernández, David A; Espinosa-Uribe, Abraham G; Mohamed-Noriega, Jibran; Cuervo-Lozano, Edgar E; Mohamed-Hamsho, Jesús; Quiroga-García, Oscar; Lugo-Guillen, Roberto A; Guzmán-López, Santos; Elizondo-Omaña, Rodrigo E

    2016-09-01

    The ethmoidal foramens are located on the medial wall of the orbit and are key reference points for intraoperative orientation. Detailed knowledge of the anatomy, bony landmarks and morphometric characteristics of the medial wall of the orbit is essential for various surgical procedures. The aim of this study was to determine the morphometric variations in the medial wall of the orbit and establish significant variations regarding age and gender. A total of 110 orbits were analyzed and subdivided by age (over or under 40 years) and gender. The distances of the medial wall of the orbit between the anterior lacrimal crest, the ethmoidal foramen, the optic canal and the interforamina were determined. Safe surgical areas were sought. Statistical tests were used to determine the differences between groups. In men, there is a safe surgical area proximal to the anterior and posterior ethmoidal foramen. In women, this area is in the posterior third of the medial wall of the orbit between the posterior ethmoidal foramen and the optic canal. Regarding variation according to age, the results of this study suggested that the anteroposterior diameter of the medial wall increases with age. This study showed that the anteroposterior total length of the medial orbit wall is similar between genders of similar age, increases with age, and has significant variations in the distances between the various structures that make up the medial orbit wall with regard to gender and age. PMID:26683469

  14. Age-related variations of protein carbonyls in human saliva and plasma: is saliva protein carbonyls an alternative biomarker of aging?

    PubMed

    Wang, Zhihui; Wang, Yanyi; Liu, Hongchen; Che, Yuwei; Xu, Yingying; E, Lingling

    2015-06-01

    Free radical hypothesis which is one of the most acknowledged aging theories was developed into oxidative stress hypothesis. Protein carbonylation is by far one of the most widely used markers of protein oxidation. We studied the role of age and gender in protein carbonyl content of saliva and plasma among 273 Chinese healthy subjects (137 females and 136 males aged between 20 and 79) and discussed the correlation between protein carbonyl content of saliva and plasma. Protein carbonyl content of saliva and plasma were, respectively, 2.391 ± 0.639 and 0.838 ± 0.274 nmol/mg. Variations of saliva and plasma different age groups all reached significant differences in both male and female (all p < 0.05) while both saliva and plasma protein carbonyls were found to be significantly correlated with age (r = 0.6582 and r = 0.5176, all p < 0.001). Gender was discovered to be unrelated to saliva and plasma protein carbonyl levels (all p > 0.05). Saliva and plasma protein carbonyls were positively related (r = 0.4405, p < 0.001). Surprisingly, saliva and plasma protein carbonyls/ferric reducing ability of plasma (FRAP) ratios were proved to be significantly correlated with age (r = 0.7796 and r = 0.6938, all p < 0.001) while saliva protein carbonyls/FRAP ratio and plasma protein carbonyls/FRAP ratio were also correlated (r = 0.5573, p < 0.001). We concluded that saliva protein carbonyls seem to be an alternative biomarker of aging while the mechanisms of protein carbonylation and oxidative stress and the relationship between saliva protein carbonyls and diseases need to be further investigated. PMID:25943699

  15. Age-related differences in the neural correlates of trial-to-trial variations of reaction time.

    PubMed

    Adleman, Nancy E; Chen, Gang; Reynolds, Richard C; Frackman, Anna; Razdan, Varun; Weissman, Daniel H; Pine, Daniel S; Leibenluft, Ellen

    2016-06-01

    Intra-subject variation in reaction time (ISVRT) is a developmentally-important phenomenon that decreases from childhood through young adulthood in parallel with the development of executive functions and networks. Prior work has shown a significant association between trial-by-trial variations in reaction time (RT) and trial-by-trial variations in brain activity as measured by the blood-oxygenated level-dependent (BOLD) response in functional magnetic resonance imaging (fMRI) studies. It remains unclear, however, whether such "RT-BOLD" relationships vary with age. Here, we determined whether such trial-by-trial relationships vary with age in a cross-sectional design. We observed an association between age and RT-BOLD relationships in 11 clusters located in visual/occipital regions, frontal and parietal association cortex, precentral/postcentral gyrus, and thalamus. Some of these relationships were negative, reflecting increased BOLD associated with decreased RT, manifesting around the time of stimulus presentation and positive several seconds later. Critically for present purposes, all RT-BOLD relationships increased with age. Thus, RT-BOLD relationships may reflect robust, measurable changes in the brain-behavior relationship across development. PMID:27239972

  16. Age-Related Declines and Disease-Associated Variation in Immune Cell Telomere Length in a Wild Mammal

    PubMed Central

    Beirne, Christopher; Delahay, Richard; Hares, Michelle; Young, Andrew

    2014-01-01

    Immunosenescence, the deterioration of immune system capability with age, may play a key role in mediating age-related declines in whole-organism performance, but the mechanisms that underpin immunosenescence are poorly understood. Biomedical research on humans and laboratory models has documented age and disease related declines in the telomere lengths of leukocytes (‘immune cells’), stimulating interest their having a potentially general role in the emergence of immunosenescent phenotypes. However, it is unknown whether such observations generalise to the immune cell populations of wild vertebrates living under ecologically realistic conditions. Here we examine longitudinal changes in the mean telomere lengths of immune cells in wild European badgers (Meles meles). Our findings provide the first evidence of within-individual age-related declines in immune cell telomere lengths in a wild vertebrate. That the rate of age-related decline in telomere length appears to be steeper within individuals than at the overall population level raises the possibility that individuals with short immune cell telomeres and/or higher rates of immune cell telomere attrition may be selectively lost from this population. We also report evidence suggestive of associations between immune cell telomere length and bovine tuberculosis infection status, with individuals detected at the most advanced stage of infection tending to have shorter immune cell telomeres than disease positive individuals. While male European badgers are larger and show higher rates of annual mortality than females, we found no evidence of a sex difference in either mean telomere length or the average rate of within-individual telomere attrition with age. Our findings lend support to the view that age-related declines in the telomere lengths of immune cells may provide one potentially general mechanism underpinning age-related declines in immunocompetence in natural populations. PMID:25268841

  17. Examining methodological variation in response inhibition: The effects of outcome measures and task characteristics on age-related differences.

    PubMed

    Klenberg, Liisa; Närhi, Vesa; Korkman, Marit; Hokkanen, Laura

    2015-01-01

    This study addressed methodological issues common to developmental studies on response inhibition. Age-related differences were investigated using two Stroop-like tasks with different levels of complexity and comparing different outcome measures in a sample of 340 children and adolescents aged 7-15 years. First, speed and accuracy of task performance were examined; the results showing that improvement in speed continued until age 13 in both the basic naming task and the two inhibition tasks. Improvement in accuracy was less consistent and continued until age 9 or 13 years. Second, two different algorithms were employed to control for the effects of basic processes in inhibition tasks. The difference algorithm indicated age-related differences similar to those for speed. The ratio algorithm, however, suggested earlier deceleration of development of response inhibition at 9 or 11 years of age. Factors related to the cognitive requirements and presented stimuli also had an effect on the results. The present findings shed light on the inconsistencies in the developmental studies of response inhibition and demonstrated that the selection of outcome measures and task characteristics are critical because they affect the way development is depicted. PMID:25175830

  18. Visual Capacity, Out-of-Home Activities and Emotional Well-Being in Old Age: Basic Relations and Contextual Variation

    ERIC Educational Resources Information Center

    Heyl, Vera; Wahl, Hans-Werner; Mollenkopf, Heidrun

    2005-01-01

    This work examined the role of visual capacity in connection with psychological, social network related, and socio-structural predictors of out-of-home everyday functioning and emotional well-being. The results are based on a sample of 1519 community dwelling elderly (55-98 years; mean age 70.8 years), 757 of them were living in urban, and 762…

  19. Genetic variations in GJA3, GJA8, LIM2, and age-related cataract in the Chinese population: a mutation screening study

    PubMed Central

    Zhou, Zhou; Wang, Binbin; Hu, Shanshan; Zhang, Chunmei; Ma, Xu

    2011-01-01

    Purpose To investigate the role of genetic variations in three known cataract-associated genes, gap junction protein α3 (GJA3), gap junction protein α8 (GJA8), lens intrinsic membrane protein 2 (LIM2), encoding lens fiber cell membrane proteins in the development of age-related cataracts. Methods One hundred and forty-five sporadic age-related cataract patients and one hundred and fifty-six unrelated random healthy controls participated in this study. Genomic DNA was extracted from peripheral blood leukocytes. All exons of GJA3, GJA8, and LIM2 were sequenced after being amplified by polymerase chain reaction (PCR). The functional consequences of the mutations were analyzed using PolyPhen. Results We found five novel variations in 145 patients and none of them presented in the 156 controls. There are two variations in GJA3 (c.-39C>G, c. 415G>A); one in GJA8 (c. 823G>A), and two in LIM2 (c.57G>A, c.67A>C). PolyPhen predicted that the LIM2 c.67A>C mutation may have potential pathogenicity. Conclusions The genetic mutation in GJA3, GJA8, and LIM2 may slightly contribute to the development of age-related cataracts. This study showed a potential relationship between lens fiber cell membrane protein genes and the development of age-related cataracts in the Chinese population. PMID:21386927

  20. Age-related variation in the adrenocortical response to stress in nestling white storks (Ciconia ciconia) supports the developmental hypothesis.

    PubMed

    Blas, Julio; Baos, Raquel; Bortolotti, Gary R; Marchant, Tracy A; Hiraldo, Fernando

    2006-09-01

    The post-natal development of the adrenocortical response to stress was investigated in European white storks. Sixty wild nestlings aged 24-59 days old were subjected to a standardized capture and restraint protocol, and the time-course pattern of the response to stress was assessed through determination of circulating corticosterone in blood samples collected at five fixed times during the 45-min period following capture. The time course of the response was best fit to a third-order function of handling time, and showed a strong effect of age. Although age did not affect baseline titers and all birds showed a positive post-capture increase in circulating corticosterone, age had a positive effect on the relative increase from baseline titer, the recorded time to reach maximum level, and the acute concentration after 10 min following capture and restraint. While young nestlings displayed very little response to capture, the response near fledging resembled the typical adrenocortical pattern widely reported in fully developed birds. Our results concur with those found in altricial and semi-altricial species, and suggest that non-precocial birds follow a similar mode of development of the hypothalamic-pituitary-adrenal (HPA) axis. The fact that HPA sensitivity to stress is functional suggests that young storks gradually develop emergency responses of adaptive value and are able to overcome acute perturbations in spite of their parental dependence, at least during the last two-thirds of post-natal development. According to the Developmental Hypothesis, such gradual changes would allow nestlings to respond to perturbations as a function of the specific behavioral and physiological abilities of their age. The potential sources of stress that nestlings have to face during development (i.e., weather conditions, dietary restrictions, and social competition) are discussed according to developmental changes in behavioral and physiological abilities. PMID:16624312

  1. PREDICTING STEEP ESCALATIONS IN ALCOHOL USE OVER THE TEENAGE YEARS: AGE-RELATED VARIATIONS IN KEY SOCIAL INFLUENCES

    PubMed Central

    Chan, Gary C. K.; Kelly, Adrian B.; Toumbourou, John W.; Hemphill, Sheryl A.; Young, Ross McD.; Haynes, Michele A.; Catalano, Richard F.

    2013-01-01

    Aims This study examined how family, peer and school factors are related to different trajectories of adolescent alcohol use at key developmental periods. Design Latent Class Growth Analysis was used to identify trajectories based on five waves of data (from Grade 6 - age 12 to Grade 11 – age 17), with predictors at Grade 5, Grade 7, and Grade 9 included as covariates. Setting Adolescents completed surveys during school hours. Participants 808 students in Victoria, Australia. Measurements Alcohol use trajectories were based on self-reports of 30 day frequency of alcohol use. Predictors included sibling alcohol use, attachment to parents, parental supervision, parental attitudes favorable to adolescent alcohol use, peer alcohol use, and school commitment. Findings 8.2% showed steep escalation in alcohol use. Relative to non-users, steep escalators were predicted by age-specific effects for low school commitment at Grade 7 (p = .031) and parental attitudes at Grade 5 (p = .003), and age-generalized effects for sibling alcohol use (ps = .001/.012/.033 at Grade 5/7/9) and peer alcohol use (ps = .041/.001/.001 at Grade 5/7/9). Poor parental supervision was associated with steep escalators at Grade 9 (p < .001) but not the other grades. Attachment to parents was unrelated to alcohol trajectories. Conclusions Parental disapproval of alcohol use before transition to high school, low school commitment at transition to high school, and sibling and peer alcohol use during adolescence are associated with higher risk of steep escalations in alcohol use. PMID:23834266

  2. Aging and Intergenerational Relations.

    ERIC Educational Resources Information Center

    Lee, Gary R.

    1987-01-01

    Considers the rapid aging of the American population and the changing age structure of society. Discusses the needs of older adults, the role of the family in providing support to older members, and issues of intergenerational relations. (NB)

  3. How often does deliberate self-harm occur relative to each suicide? A study of variations by gender and age.

    PubMed

    Hawton, Keith; Harriss, Louise

    2008-12-01

    Deliberate self-harm (DSH; i.e., nonfatal self-poisoning or self-injury) occurs much more frequently than suicide, yet there has been little detailed investigation of the comparative rates of DSH and suicide. We conducted a study of how rates of DSH relate to suicide rates across the life cycle by gender and by method of estimation of DSH rates, using 10 years of data from a local system for monitoring DSH presentations to a general hospital and national and local suicide statistics. The rate-ratio of DSH to suicide was 36 (95% CI 34.9-37.1) based on annual person-based rates of DSH episodes and was nearly five times higher in females (87.9; 95% CI 84.4-91.6) than in males (18.7; 95% CI 17.9-19.6). The ratio varied markedly across the life cycle, decreasing from more than 200 in teenagers to less than 10 in persons aged 60 years and over. The difference in the ratio between females and males also decreased over the life cycle. There were very similar findings when local suicide rates were used. These patterns were replicated when the data were analyzed, first, on the basis of all episodes of DSH during the study period, but with expectedly larger DSH:suicide ratios (e.g., overall 52.7; 95% CI 51.4-54.1), and second, on the basis of individual persons only engaging in DSH during the study period, but with smaller ratios (e.g., overall 26.2; 95% CI 25.4-27.2). The DSH:suicide rate ratios for those with high and low suicidal intent were similar within age groups except for those aged 60 years and over, in whom there was a greater proportion of high intent acts. These findings illustrate how the nature of self-harming behavior may vary in intention across the life cycle and between the genders, and provide a basis for further comparative work of this kind. PMID:19152296

  4. Variations in highway stormwater runoff quality and stormwater treatment performance in relation to the age of porous friction courses.

    PubMed

    Moores, Jonathan P; Pattinson, Peter E; Hyde, Christian R

    2013-09-01

    A program of highway runoff sampling was conducted at four sites in Auckland, New Zealand. Concentrations of suspended solids, particulate copper, and zinc were significantly lower in runoff from a highway paved with a 1-year-old porous friction course (PFC) than in runoff at the other sites. Differences in total metal concentrations were less marked, reflecting relatively high concentrations of dissolved copper and zinc in runoff from the 1-year-old PFC. Runoff quality at a highway site that had been paved with a PFC 6 years previously was similar to that discharged from two impermeable roads, indicating a reduction over time in the quality of runoff discharged from PFCs. Runoff from the highways paved with 1- and 6-year-old PFCs was treated by a grass swale and wet pond, respectively. Both treatments were effective, the former predominantly through the lowering of dissolved metal concentrations and the latter through the lowering of particulate metal concentrations. These results indicate that stormwater treatment can improve the quality of runoff discharged from PFCs, irrespective of their age, provided that treatment is targeted to the predominant contaminant phase present. PMID:24175407

  5. Aging-related viscoelasticity variation of tendon stem cells (TSCs) characterized by quartz thickness shear mode (TSM) resonators

    PubMed Central

    Wu, Huiyan; Zhao, Guangyi; Zu, Hongfei; Wang, James H.-C.; Wang, Qing-Ming

    2015-01-01

    Aging not only affects the whole body performance but also alters cellular biological properties, including cell proliferation and differentiation. This study was designed to determine the effect of aging on the mechanical properties of tendon stem cells (TSCs), a newly discovered stem cell type in tendons, using quartz thickness shear mode (TSM) resonators. TSCs were isolated from both old and young rats, and allowed to grow to confluency on the surface of TSM resonators. The admittance spectrums of TSM with TSC monolayer were acquired, and a series of complex shear modulus G′ + jG″ as well as average thickness hTSC were calculated based on a two-layer-loading transmission line model (TLM) for TSM resonator sensor. The results showed an overall increase in G′, G″ and hTSC during aging process. Specifically, the storage modulus G′ of aging TSCs was over ten times than that of young, revealing an important increase in stiffness of aging TSCs. Additionally, through phase-contrast and scanning electronic microscopy, it was shown that aging TSCs were large, flat and heterogeneous in morphologies while young TSCs were uniformly elongated. Increased cell size and irregular cell shape might be associated with the dense cytoskeleton organization, which could lead to an increase in both stiffness and viscosity. These results are in agreement with previously published data using different measurement methods, indicating TSM resonator sensor as a promising tool to measure the mechanical properties of cells. PMID:26251564

  6. Variation of the lunar highland surface roughness at baseline 0.15-100 km and the relationship to relative age

    NASA Astrophysics Data System (ADS)

    Yokota, Y.; Gwinner, K.; Oberst, J.; Haruyama, J.; Matsunaga, T.; Morota, T.; Noda, H.; Araki, H.; Ohtake, M.; Yamamoto, S.; Gläser, P.; Ishihara, Y.; Honda, C.; Hirata, N.; Demura, H.

    2014-03-01

    We report the surface roughness analysis of the lunar highlands for the baseline range 0.15-100 km. We use the Median Differential Slope αm to investigate the scale dependency of the roughness and derive the global αm distribution from SELENE Laser Altimeter and Terrain Camera data. While αm(l) versus baseline l (km) plots vary among different highland types, all highlands commonly show a peak at 3-30 km. The Pre-Nectarian surface shows a relatively large αm(20-30 km). Our analysis is supported by the simulation of synthetic surface cratering models and crater statistics. In our simulation, a peak of αm(30 km) is successfully reproduced. The actual crater density shows good correlation with an empirical roughness indicator. However, a large part of the Nectarian surface shows a peak at 6-9 km baseline. This peak may be caused by secondary craters and ejecta deposit textures from the Nectarian system basins.

  7. The face of appearance-related social pressure: gender, age and body mass variations in peer and parental pressure during adolescence

    PubMed Central

    2013-01-01

    Background Appearance-related social pressure plays an important role in the development of a negative body image and self-esteem as well as severe mental disorders during adolescence (e.g. eating disorders, depression). Identifying who is particularly affected by social pressure can improve targeted prevention and intervention, but findings have either been lacking or controversial. Thus the aim of this study is to provide a detailed picture of gender, weight, and age-related variations in the perception of appearance-related social pressure by peers and parents. Methods 1112 German students between grades 7 and 9 (mean age: M = 13.38, SD = .81) filled in the Appearance-Related Social Pressure Questionnaire (German: FASD), which considers different sources (peers, parents) as well as various kinds of social pressure (e.g. teasing, modeling, encouragement). Results Girls were more affected by peer pressure, while gender differences in parental pressure seemed negligible. Main effects of grade-level suggested a particular increase in indirect peer pressure (e.g. appearance-related school and class norms) from early to middle adolescence. Boys and girls with higher BMI were particularly affected by peer teasing and exclusion as well as by parental encouragement to control weight and shape. Conclusion The results suggest that preventive efforts targeting body concerns and disordered eating should bring up the topic of appearance pressure in a school-based context and should strengthen those adolescents who are particularly at risk - in our study, girls and adolescents with higher weight status. Early adolescence and school transition appear to be crucial periods for these efforts. Moreover, the comprehensive assessment of appearance-related social pressure appears to be a fruitful way to further explore social risk-factors in the development of a negative body image. PMID:23680225

  8. Costs and Benefits of Children's Physical and Relational Aggression Trajectories on Peer Rejection, Acceptance, and Friendships: Variations by Aggression Subtypes, Gender, and Age

    ERIC Educational Resources Information Center

    Ettekal, Idean; Ladd, Gary W.

    2015-01-01

    This study examined the associations between children's co-occurring relational and physical aggression trajectories and their peer relations (i.e., peer rejection, peer acceptance, and reciprocated friendships) from late childhood (Grade 4; M[subscript age] = 10.0) to early adolescence (Grade 8; M[subscript age] = 13.9). Using a sample of 477…

  9. Pharmacogenetic effects of angiotensin-converting enzyme inhibitors over age-related urea and creatinine variations in patients with dementia due to Alzheimer disease

    PubMed Central

    Berretta, Juliana Marília; Suchi Chen, Elizabeth; Cardoso Smith, Marilia; Ferreira Bertolucci, Paulo Henrique

    2016-01-01

    Background: Renal function declines according to age and vascular risk factors, whereas few data are available regarding genetically-mediated effects of anti-hypertensives over renal function. Objective: To estimate urea and creatinine variations in dementia due to Alzheimer disease (AD) by way of a pharmacogenetic analysis of the anti-hypertensive effects of angiotensin-converting enzyme inhibitors (ACEis). Methods: Consecutive outpatients older than 60 years-old with AD and no history of kidney transplant or dialytic therapy were recruited for prospective correlations regarding variations in fasting blood levels of urea and creatinine in one year, considering ACE genotypes of rs1800764 and rs4291 and their respective haplotypes, and treatment with ACEis along with blood pressure variations. Results: For 190 patients, 152 had arterial hypertension, and 122 used ACEis. Minor allele frequencies were 0.492 for rs1800764-C and 0.337 for rs4291-T, both in Hardy-Weinberg equilibrium. There were no overall significant yearly variations in levels of urea and creatinine, but their concurrent variations were positively correlated (ρ <0.0001). Each A allele of rs4291 led to an yearly urea increase of 3,074 mg/dL, and an yearly creatinine increase of 0.044 mg/dL, while the use of ACEis was protective regarding creatinine variations. The use of ACEis was also protective for carriers of rs1800764-CT/rs4291-AA, while carriers of rs1800764-CT/rs4291-AT had steeper reductions in creatinine levels, particularly when they were treated with ACEis. Conclusions: Effects of ACEis over creatinine variations are genetically mediated and independent of blood pressure variations in older people with AD. PMID:27546928

  10. Age-Related Macular Degeneration

    MedlinePlus

    ... this page please turn Javascript on. Age-related Macular Degeneration What is AMD? Click for more information Age-related macular degeneration, ... the macula allows you to see fine detail. AMD Blurs Central Vision AMD blurs the sharp central ...

  11. Memory Development: Sources of the Age Variation.

    ERIC Educational Resources Information Center

    von Eye, Alexander; Hussy, Walter

    Research has not clearly determined whether memory development in childhood and adulthood can be accounted for by the age variation of cognitive processes other than memory. To examine this issue, a study was conducted based on a model of structures and processes in complex information processing. Subjects (N=162) were presented with two lists of…

  12. A Comprehensive Survey of Sequence Variation in the ABCA4 (ABCR) Gene in Stargardt Disease and Age-Related Macular Degeneration

    PubMed Central

    Rivera, Andrea; White, Karen; Stöhr, Heidi; Steiner, Klaus; Hemmrich, Nadine; Grimm, Timo; Jurklies, Bernhard; Lorenz, Birgit; Scholl, Hendrik P. N.; Apfelstedt-Sylla, Eckhart; Weber, Bernhard H. F.

    2000-01-01

    Stargardt disease (STGD) is a common autosomal recessive maculopathy of early and young-adult onset and is caused by alterations in the gene encoding the photoreceptor-specific ATP-binding cassette (ABC) transporter (ABCA4). We have studied 144 patients with STGD and 220 unaffected individuals ascertained from the German population, to complete a comprehensive, population-specific survey of the sequence variation in the ABCA4 gene. In addition, we have assessed the proposed role for ABCA4 in age-related macular degeneration (AMD), a common cause of late-onset blindness, by studying 200 affected individuals with late-stage disease. Using a screening strategy based primarily on denaturing gradient gel electrophoresis, we have identified in the three study groups a total of 127 unique alterations, of which 90 have not been previously reported, and have classified 72 as probable pathogenic mutations. Of the 288 STGD chromosomes studied, mutations were identified in 166, resulting in a detection rate of ∼58%. Eight different alleles account for 61% of the identified disease alleles, and at least one of these, the L541P-A1038V complex allele, appears to be a founder mutation in the German population. When the group with AMD and the control group were analyzed with the same methodology, 18 patients with AMD and 12 controls were found to harbor possible disease-associated alterations. This represents no significant difference between the two groups; however, for detection of modest effects of rare alleles in complex diseases, the analysis of larger cohorts of patients may be required. PMID:10958763

  13. Confidant Relations of the Aged.

    ERIC Educational Resources Information Center

    Tigges, Leann M.; And Others

    The confidant relationship is a qualitatively distinct dimension of the emotional support system of the aged, yet the composition of the confidant network has been largely neglected in research on aging. Persons (N=940) 60 years of age and older were interviewed about their socio-environmental setting. From the enumeration of their relatives,…

  14. The Variation with Age of 67 Macro- and Microelement Contents in Nonhyperplastic Prostate Glands of Adult and Elderly Males Investigated by Nuclear Analytical and Related Methods.

    PubMed

    Zaichick, Vladimir

    2015-11-01

    To clarify age-related changes of 67 macro- and microelement contents in prostate gland of adult and geriatric males, a quantitative measurement by five analytical methods was performed. The nonhyperplastic prostate glands of 65 subjects (European-Caucasian aged 21-87 years) were investigated by energy dispersive X-ray fluorescence (EDXRF), instrumental neutron activation analysis with high resolution spectrometry of short-lived radionuclides (INAA-SLR), instrumental neutron activation analysis with high resolution spectrometry of long-lived radionuclides (INAA-LLR), inductively coupled plasma atomic emission spectrometry (ICP-AES), and inductively coupled plasma mass spectrometry (ICP-MS). The prostates were obtained at autopsy from subjects who died from acute illness (cardiac insufficiency, stroke, embolism of pulmonary artery, alcohol poisoning) and trauma. None of the subjects had any symptoms of prostatic disease, and all prostates were classified as histologically normal. The combination of nuclear (EDXRF, INAA-SLR, and INAA-LLR) and inductively coupled plasma (ICP-AES and ICP-MS) analytical methods allowed estimation of the contents of 67 chemical elements and precisely determined the mass fraction of 54 elements in the tissue samples of nonhyperplastic adult and geriatric prostate glands. This work's results reveal that there is a significant increase with age of Bi, Cd, Co, Fe, Hg, Pb, Sc, Sn, Th, U, and Zn mass fractions in the prostate tissue of healthy individuals of ages from 21 to 60 years, as well as an increase in Ba from age 61 up to 87 years. It implies that an age-related increase and excess in Ba, Bi, Cd, Co, Fe, Hg, Pb, Sc, Sn, Th, U, and Zn mass fraction in prostatic tissue may be one of the main factors in the etiology of benign prostatic hyperplasia (BPH) and prostate carcinoma (PCa). PMID:25940729

  15. Variation of DNA methylation in candidate age-related targets on the mitochondrial-telomere axis in cord blood and placenta

    PubMed Central

    Janssen, B.G.; Byun, HM.; Cox, B.; Gyselaers, W.; Izzi, B.; Baccarelli, A.A.; Nawrot, T.S.

    2015-01-01

    Background Epigenetics is tissue-specific and potentially even cell-specific, but little information is available from human reproductive studies about the concordance of DNA methylation patterns in cord blood and placenta, as well as within-placenta variations. We evaluated methylation levels at promoter regions of candidate genes in biological ageing pathways (SIRT1, TP53, PPARG, PPARGC1A, and TFAM), a subtelomeric region (D4Z4) and the mitochondrial genome (MT-RNR1, D-loop). Methods Ninety individuals were randomly chosen from the ENVIRONAGE birth cohort to evaluate methylation concordance between cord blood and placenta using highly quantitative bisulfite-PCR pyrosequencing. In a subset of nineteen individuals, a more extensive sampling scheme was performed to examine within-placenta variation. Results The DNA methylation levels of the subtelomeric region and mitochondrial genome showed concordance between cord blood and placenta with correlation coefficients ranging from r = 0.31 to 0.43, p ≤ 0.005, and also between the maternal and foetal sides of placental tissue (r = 0.53 to 0.72, p ≤ 0.05). For the majority of targets, an agreement in methylation levels between four foetal biopsies was found (with intra-class correlation coefficients ranging from 0.16 to 0.72), indicating small within-placenta variation. Conclusions The methylation levels of the subtelomeric region (D4Z4) and mitochondrial genome (MT-RNR1, D-loop) showed concordance between cord blood and placenta, suggesting a common epigenetic signature of these targets between tissues. Concordance was lacking between the other genes that were studied. In placental tissue, methylation patterns of most targets on the mitochondrial-telomere axis were not strongly influenced by sample location. PMID:25047690

  16. Macular degeneration - age-related

    MedlinePlus

    Age-related macular degeneration (ARMD); AMD ... distorted and wavy. There may be a small dark spot in the center of your vision that ... leafy vegetables, may also decrease your risk of age-related macular degeneration. If you have wet AMD, ...

  17. Normal Genetic Variation, Cognition, and Aging

    PubMed Central

    Greenwood, P. M.; Parasuraman, Raja

    2005-01-01

    This article reviews the modulation of cognitive function by normal genetic variation. Although the heritability of “g” is well established, the genes that modulate specific cognitive functions are largely unidentified. Application of the allelic association approach to individual differences in cognition has begun to reveal the effects of single nucleotide polymorphisms on specific and general cognitive functions. This article proposes a framework for relating genotype to cognitive phenotype by considering the effect of genetic variation on the protein product of specific genes within the context of the neural basis of particular cognitive domains. Specificity of effects is considered, from genes controlling part of one receptor type to genes controlling agents of neuronal repair, and evidence is reviewed of cognitive modulation by polymorphisms in dopaminergic and cholinergic receptor genes, dopaminergic enzyme genes, and neurotrophic genes. Although allelic variation in certain genes can be reliably linked to cognition—specifically to components of attention, working memory, and executive function in healthy adults—the specificity, generality, and replicability of the effects are not fully known. PMID:15006290

  18. [Age-related macular degeneration].

    PubMed

    Budzinskaia, M V

    2014-01-01

    The review provides an update on the pathogenesis and new treatment modalities for neovascular age-related macular degeneration (AMD). The impact of polymorphism in particular genes, including complement factor H (CFH), age-related maculopathy susceptibility 2 (ARMS2/LOC387715), and serine peptidase (HTRA1), on AMD development is discussed. Clinical presentations of different forms of exudative AMD, that is classic, occult, or more often mixed choroidal neovascularization, retinal angiomatous proliferation, and choroidal polypoidal vasculopathy, are described. Particular attention is paid to the results of recent clinical trials and safety issues around the therapy. PMID:25715554

  19. Diurnal and temporal variations of water-soluble dicarboxylic acids and related compounds in aerosols from the northern vicinity of Beijing: implication for photochemical aging during atmospheric transport.

    PubMed

    He, Nannan; Kawamura, Kimitaka; Okuzawa, K; Pochanart, P; Liu, Y; Kanaya, Y; Wang, Z F

    2014-11-15

    Aerosol samples were collected in autumn 2007 on day- and nighttime basis in the northern receptor site of Beijing, China. The samples were analyzed for total carbon (TC) and water-soluble dicarboxylic acids (C2-C12), oxocarboxylic acids (C2-C9), glyoxal and methylglyoxal to better understand the photochemical aging of organic aerosols in the vicinity of Beijing. Concentrations of TC are 50% greater in daytime when winds come from Beijing than in nighttime when winds come from the northern forest areas. Most diacids showed higher concentrations in daytime, suggesting that the organics emitted from the urban Beijing and delivered to the northern vicinity in daytime are subjected to photo-oxidation to result in diacids. However, oxalic acid (C2), which is the most abundant diacid followed by C3 or C4, became on average 30% more abundant in nighttime together with azelaic, ω-oxooctanoic and ω-oxononanoic acids, which are specific oxidation products of biogenic unsaturated fatty acids. Methylglyoxal, an oxidation product of isoprene and a precursor of oxalic acid, also became 29% more abundant in nighttime. Based on a positive correlation between C2 and glyoxylic acid (ωC2) in nighttime when relative humidity significantly enhanced, we propose a nighttime aqueous phase production of C2 via the oxidation of ωC2. We found an increase in the contribution of diacids to TC by 3 folds during consecutive clear days. This study demonstrates that diacids and related compounds are largely produced in the northern vicinity of Beijing via photochemical processing of organic precursors emitted from urban center and forest areas. PMID:25181047

  20. Age-related hearing loss

    MedlinePlus

    ... is no known single cause of age-related hearing loss. Most commonly, it is caused by changes in the inner ear that occur as you grow older. Your genes and loud noise (from rock concerts or music headphones) may play a large role. The following ...

  1. Effect of High-Density Lipoprotein Metabolic Pathway Gene Variations and Risk Factors on Neovascular Age-Related Macular Degeneration and Polypoidal Choroidal Vasculopathy in China

    PubMed Central

    Sun, Yaoyao; Bai, Yujing; Wang, Bin; Yu, Wenzhen; Zhao, Mingwei; Li, Xiaoxin

    2015-01-01

    Purpose To investigate the effect of genetic variants in the high-density lipoprotein (HDL) metabolic pathway and risk factors on neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV) in China. Methods A total of 742 Chinese subjects, including 221 controls, 230 cases with nAMD, and 291 cases with PCV, were included in the present study. Five single nucleotide polymorphisms (SNPs) from three genes in the HDL metabolic pathway (HDLMP) including cholesteryl ester transfer protein (CETP), hepatic lipase (LIPC) and lipoprotein lipase (LPL) were genotyped in all study subjects with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Risk factors including gender, hypertension, hyperlipidemia, diabetes mellitus, and coronary artery disease were identified. Chi-square tests or Fisher’s exact tests were applied to discover associations between SNPs and risk factors for PCV and nAMD. Gene-gene interactions and gene-environment interactions were evaluated by the multifactor-dimensionality reduction (MDR) method. Results CETP rs3764261 were significantly associated with an increased risk for PCV (odds ratio (OR) = 1.444, P = 0.0247). LIPC rs1532085 conferred an increased risk for PCV (OR = 1.393, P = 0.0094). We found no association between PCV and LPL rs12678919, LIPC rs10468017 or CETP rs173539. No association was found between five SNPs with nAMD. Regarding risk factors, females were found to have significantly decreased risks for both PCV and nAMD (P = 0.006 and 0.001, respectively). Coronary artery disease (CAD) was a risk factor in PCV patients but played a protective role in nAMD patients. Hyperlipidemia was associated with PCV but not with nAMD. Neither hypertension nor diabetes mellitus was associated with PCV or nAMD. The MDR analysis revealed that a three-locus model with rs12678919, rs1532085, and gender was the best model for nAMD, while a five-locus model consisting of rs

  2. [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

  3. [Age-related macular degeneration].

    PubMed

    Garcia Layana, A

    1998-01-01

    Age-related macular degeneration (ARMD) is the leading cause of blindness in the occidental world. Patients suffering this process have an important reduction on their quality of life being handicapped to read, to write, to recognise faces of their friends, or even to watch the television. One of the main problems of that disease is the absence of an effective treatment able to revert the process. Laser treatment is only useful in a limited number of patients, and even in these cases recurrent lesions are frequent. These facts and the progressive ageing of our society establish the ARMD as one of the biggest aim of medical investigations for the next century, and currently is focus of attention in the most industrialised countries. One of the most promising pieces of research is focused in the investigation of the risk factors associated with the age-related macular degeneration, in order to achieve a prophylactic treatment avoiding its appearance. Diet elements such as fat ingestion or reduced antioxidant intakes are being investigated as some of these factors, what open a new possibility for a prophylactic treatment. Finally, research is looking for new therapeutic modalities such as selective radiotherapy in order to improve or maintain the vision of these patients. PMID:10420956

  4. Costs and benefits of children's physical and relational aggression trajectories on peer rejection, acceptance, and friendships: Variations by aggression subtypes, gender, and age.

    PubMed

    Ettekal, Idean; Ladd, Gary W

    2015-12-01

    This study examined the associations between children's co-occurring relational and physical aggression trajectories and their peer relations (i.e., peer rejection, peer acceptance, and reciprocated friendships) from late childhood (Grade 4; Mage = 10.0) to early adolescence (Grade 8; Mage = 13.9). Using a sample of 477 children (240 girls), the findings indicated there were multiple heterogeneous subgroups of children who followed distinct co-occurring aggression trajectories. For each of these subgroups, multiple indices of their relational development were assessed and findings revealed notable group differences. These results have implications about the potential costs and benefits of aggression, and how its associations with children's peer relationships may vary as a function of aggression subtype, developmental timing, and gender. PMID:26414097

  5. Spatial Variation in the Storages and Age-Related Dynamics of Forest Carbon Sequestration in Different Climate Zones—Evidence from Black Locust Plantations on the Loess Plateau of China

    PubMed Central

    Li, Taijun; Ren, Bowen; Wang, Dahui; Liu, Guobin

    2015-01-01

    Knowledge about the long-term influences of climate change on the amount of potential carbon (C) sequestration in forest ecosystems, including age-related dynamics, remains unclear. This study used two similar age-sequences of black locust forests (Robinia pseudoacacia L.) in the semi-arid and semi-humid zones of China’s Loess Plateau to assess the variation in C stocks and age-related dynamics. Our results demonstrated that black locust forests of the semi-humid zone stored significantly more C than did forests in the semi-arid zone, across the chronosequence (p < 0.001). The C carrying capacity of the plantations was measured at 166.4 Mg C ha−1 (1 Mg = 106 g) in the semi-humid zone, while the semi-arid zone had a capacity of only 79.4 Mg C ha−1. Soil organic C (SOC) increased continuously with stand age in the semi-arid zone (R2 = 0.84, p = 0.010). However, in the semi-humid zone, SOC declined sharply by 47.8% after the initial stage (5 to 10 y). The C stock in trees increased continuously with stand age in the semi-humid zone (R2 = 0.83, p = 0.011), yet in the semi-arid zone, it decreased dramatically from 43.0 Mg C ha−1 to 28.4 Mg C ha−1 during the old forest stage (38 to 56 y). The shift from being a net C sink to a net C source occurred at the initial stage in the semi-humid zone versus at the old forest stage in the semi-arid zone after reforestation. Surprisingly, with the exception of the initial and later stages (55 y), the patterns of C allocation among trees, soils, understory and litter were not statistically different between the two climate zones. Our results suggest that climate factors can alter the potential amount and age-related dynamics of forest C sequestration. PMID:25799100

  6. Spatial variation in the storages and age-related dynamics of forest carbon sequestration in different climate zones-evidence from black locust plantations on the Loess Plateau of China.

    PubMed

    Li, Taijun; Ren, Bowen; Wang, Dahui; Liu, Guobin

    2015-01-01

    Knowledge about the long-term influences of climate change on the amount of potential carbon (C) sequestration in forest ecosystems, including age-related dynamics, remains unclear. This study used two similar age-sequences of black locust forests (Robinia pseudoacacia L.) in the semi-arid and semi-humid zones of China's Loess Plateau to assess the variation in C stocks and age-related dynamics. Our results demonstrated that black locust forests of the semi-humid zone stored significantly more C than did forests in the semi-arid zone, across the chronosequence (p < 0.001). The C carrying capacity of the plantations was measured at 166.4 Mg C ha-1 (1 Mg = 106 g) in the semi-humid zone, while the semi-arid zone had a capacity of only 79.4 Mg C ha-1. Soil organic C (SOC) increased continuously with stand age in the semi-arid zone (R2 = 0.84, p = 0.010). However, in the semi-humid zone, SOC declined sharply by 47.8% after the initial stage (5 to 10 y). The C stock in trees increased continuously with stand age in the semi-humid zone (R2 = 0.83, p = 0.011), yet in the semi-arid zone, it decreased dramatically from 43.0 Mg C ha-1 to 28.4 Mg C ha-1 during the old forest stage (38 to 56 y). The shift from being a net C sink to a net C source occurred at the initial stage in the semi-humid zone versus at the old forest stage in the semi-arid zone after reforestation. Surprisingly, with the exception of the initial and later stages (55 y), the patterns of C allocation among trees, soils, understory and litter were not statistically different between the two climate zones. Our results suggest that climate factors can alter the potential amount and age-related dynamics of forest C sequestration. PMID:25799100

  7. Pathophysiology of ageing, longevity and age related diseases

    PubMed Central

    Bürkle, Alexander; Caselli, Graziella; Franceschi, Claudio; Mariani, Erminia; Sansoni, Paolo; Santoni, Angela; Vecchio, Giancarlo; Witkowski, Jacek M; Caruso, Calogero

    2007-01-01

    On April 18, 2007 an international meeting on Pathophysiology of Ageing, Longevity and Age-Related Diseases was held in Palermo, Italy. Several interesting topics on Cancer, Immunosenescence, Age-related inflammatory diseases and longevity were discussed. In this report we summarize the most important issues. However, ageing must be considered an unavoidable end point of the life history of each individual, nevertheless the increasing knowledge on ageing mechanisms, allows envisaging many different strategies to cope with, and delay it. So, a better understanding of pathophysiology of ageing and age-related disease is essential for giving everybody a reasonable chance for living a long and enjoyable final part of the life. PMID:17683521

  8. Age, geochemistry and melt flux variations for the Hawaiian Ridge

    NASA Astrophysics Data System (ADS)

    Garcia, M. O.; Weis, D. A.; Greene, A. R.; Wessel, P.; Harrison, L.; Tree, J.

    2012-12-01

    The Hawaiian Ridge portion of the Hawaiian-Emperor Chain, the classic example of a mantle plume produced linear island chain, is 6000 km in length, active for 80+ Myr, and tectonically simple. Despite its importance to our understanding of mantle plumes and Cenozoic plate motion, there are large data gaps for the age and geochemistry of lavas from volcanoes along the Hawaiian Ridge (HR) portion of the Chain. Ages: Only volcanoes near the Hawaiian-Emperor bend and in the Hawaiian Islands have modern Ar-Ar ages, leaving a gap of 2000 km where existing K-Ar ages suggest synchronous volcanism over a 1000 km section. Geochemistry: There is a 2900 km gap in high precision geochemical data for the HR. The Emperor Seamounts (>45 Ma) have better regional coverage of recent isotopic data and show a correlation of Sr isotope composition with age of the underlying oceanic lithosphere (Regelous et al. 2003). The HR has an unexplained, exponential increase in magma flux over the last 30 Myr (Vidal & Bonneville 2004). Potential explanations for the increase in magma flux include: changes in melting conditions (temperature and/or pressure), change in source fertility related to rock type (pyroxenite vs. peridotite) or previous melting history, and/or changes in plate stresses resulting from reconfigurations of plate motion. Our new multi-disciplinary project will: 1) Determine 40Ar/39Ar ages, and whole-rock major, trace element, and Pb, Sr, Nd and Hf isotopic geochemistry for lavas from 20 volcanoes spanning ~2150 km of the HR (NW of the Hawaiian Islands). 2) Use the geochemical data to determine the long-term evolution of the Hawaiian mantle plume source components and to evaluate whether there have been systematic variations in mantle potential temperature, melting pressure, and/or source lithology during the creation of the HR. If so, are they responsible for the 300% variation in melt production along the Ridge? Also, we will assess when the more fertile Loa source component

  9. Overcoming Age-Related Differences

    ERIC Educational Resources Information Center

    Agullo, Gloria Luque

    2006-01-01

    One of the most controversial issues in foreign language (FL) teaching is the age at which language learning should start. Nowadays it is recognized that in second language contexts maturational constraints make an early start advisable, but there is still disagreement regarding the problem of when to start or the best way to learn in foreign…

  10. Nutrition and age-related eye diseases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vision loss among the elderly is an important health problem. Approximately one person in three has some form of vision-reducing eye disease by the age of 65 [1]. Age-related cataract, age-related macular degeneration (AMD), diabetic retinopathy and glaucoma are the major diseases resulting in visu...

  11. Age-Related Declines Evident Before 60

    MedlinePlus

    ... Services, or federal policy. More Health News on: Exercise for Seniors Healthy Aging Recent Health News Related MedlinePlus Health Topics Exercise for Seniors Healthy Aging About MedlinePlus Site Map FAQs Contact Us Get ...

  12. Glycoconjugate changes in aging and age-related diseases.

    PubMed

    Ando, Susumu

    2014-01-01

    The significance of glycosphingolipids and glycoproteins is discussed in their relation to normal aging and pathological aging, aging with diseases. Healthy myelin that looks stable is found to be gradually degraded and reconstructed throughout life for remodeling. An exciting finding is that myelin P0 protein is located in neurons and glycosylated in aging brains. In pathological aging, the roles of glycosphingolipids and glycoproteins as risk factors or protective agents for Alzheimer's and Parkinson's diseases are discussed. Intensive studies have been performed aiming to remove the risks from and to restore the functional deficits of the brain. Some of them are expected to be translated to therapeutic means. PMID:25151390

  13. Long noncoding RNAs in aging and age-related diseases.

    PubMed

    Kour, Sukhleen; Rath, Pramod C

    2016-03-01

    Aging is the universal, intrinsic, genetically-controlled, evolutionarily-conserved and time-dependent intricate biological process characterised by the cumulative decline in the physiological functions and their coordination in an organism after the attainment of adulthood resulting in the imbalance of neurological, immunological and metabolic functions of the body. Various biological processes and mechanisms along with altered levels of mRNAs and proteins have been reported to be involved in the progression of aging. It is one of the major risk factors in the patho-physiology of various diseases and disorders. Recently, the discovery of pervasive transcription of a vast pool of heterogeneous regulatory noncoding RNAs (ncRNAs), including small ncRNAs (sncRNAs) and long ncRNAs (lncRNAs), in the mammalian genome have provided an alternative way to study and explore the missing links in the aging process, its mechanism(s) and related diseases in a whole new dimension. The involvement of small noncoding RNAs in aging and age-related diseases have been extensively studied and recently reviewed. However, lncRNAs, whose function is far less explored in relation to aging, have emerged as a class of major regulators of genomic functions. Here, we have described some examples of known as well as novel lncRNAs that have been implicated in the progression of the aging process and age-related diseases. This may further stimulate research on noncoding RNAs and the aging process. PMID:26655093

  14. Heredity vs. Environment: The Effects of Genetic Variation with Age

    ERIC Educational Resources Information Center

    Gourlay, N.

    1978-01-01

    Major problems in the field are presented through a brief review of Burt's work and a critical account of the Hawaiian and British schools of biometrical genetics. The merits and demerits of Christopher Jencks' study are also discussed. There follows an account of the principle of genetic variation with age, a new concept to the…

  15. Sports-Related Eye Injuries by Age

    MedlinePlus

    Sports-Related Eye Injuries by Age Activity Estimated Injuries* Ages 0–14 Ages 15+ Basketball 5,237 ... Exercise, Weightlifting) 1,697 401 1,297 Racquet Sports 1,241 233 1,008 Ball Sports, Unspecified ...

  16. 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…

  17. Variations of relative humidity in relation to meningitis in Africa

    NASA Astrophysics Data System (ADS)

    Seefeldt, M. W.; Hopson, T. M.

    2011-12-01

    The meningitis belt is a region covering Sub-Saharan Africa from the Sahel of West Africa eastward to western Ethiopia. The region is prone to meningitis epidemics during the dry season extending from approximately January to May, depending on the region. Relative humidity has been found to be a critical environmental factor indicating the susceptibility of a region to meningitis epidemics. This study evaluates the variation of relative humidity across West Africa over 30 dry-seasons (1979 - 2009) using the NASA-MERRA dataset. The method of self-organizing maps is employed to characterize the changes in relative humidity patterns across the region within a given dry season as well as changes over the 30 years. A general pattern of changes in relative humidity is indicated as the rainbelt retreats to the south at the onset of the dry season and then returns to the region at the end of the dry season. Within each dry season there is a unique pattern. The climatological conditions of relative humidity at the onset of the dry season provide an indication of the moisture environment for the entire dry season. Year to year variation in the relative humidity patterns are found to be gradual. Future applications involve using the results from the SOM evaluation to be used for future decisions involving prevention of meningitis epidemics.

  18. Morphometric analysis of variation in the sternum with sex and age.

    PubMed

    Weaver, Ashley A; Schoell, Samantha L; Nguyen, Callistus M; Lynch, Sarah K; Stitzel, Joel D

    2014-11-01

    Age and sex-related variations in sternum morphology may affect the thoracic injury tolerance. Male and female sternum size and shape variation was characterized for ages 0-100 from landmarks collected from 330 computed tomography scans. Homologous landmarks were analyzed using Procrustes superimposition to produce age and sex-specific functions of 3D-sternum morphology representing the combined size and shape variation and the isolated shape variation. Significant changes in the combined size and shape variation and isolated shape variation of the sternum were found to occur with age in both sexes. Sternal size increased from birth through age 30 and retained a similar size for ages 30-100. The manubrium expanded laterally from birth through age 30, becoming wider in relation to the sternal body. In infancy, the manubrium was 1.1-1.2 times the width of the sternal body and this width ratio increased to 1.6-1.8 for adults. The manubrium transformed from a circular shape in infancy to an oval shape in early childhood. The distal sternal body became wider in relation to the proximal sternal body from birth through age 30 and retained this characteristic throughout adulthood. The most dramatic changes in sternum morphology occur in childhood and young adulthood when the sternum is undergoing ossification. The lesser degree of ossification in the pediatric sternum may be partly responsible for the prevalence of thoracic organ injuries as opposed to thoracic skeletal injuries in pediatrics. Sternum fractures make up a larger portion of thoracic injury patterns in adults with fully ossified sternums. The lack of substantial size or shape changes in the sternum from age 30-100 suggests that the increased incidence of sternal fracture seen in the elderly may be due to cortical thickness or bone mineral density changes in the sternum as opposed to morphological changes. PMID:24935890

  19. Age-Related Changes in Creative Thinking

    ERIC Educational Resources Information Center

    Roskos-Ewoldsen, Beverly; Black, Sheila R.; Mccown, Steven M.

    2008-01-01

    Age-related differences in cognitive processes were used to understand age-related declines in creativity. According to the Geneplore model (Finke, Ward, & Smith, 1992), there are two phases of creativity--generating an idea and exploring the implications of the idea--each with different underlying cognitive processes. These two phases are…

  20. Seasonal Variations of Stratospheric Age Spectra in GEOSCCM

    NASA Technical Reports Server (NTRS)

    Li, Feng; Waugh, Darryn; Douglass, Anne R.; Newman, Paul A.; Pawson, Steven; Stolarski, Richard S.; Strahan, Susan E.; Nielsen, J. Eric

    2011-01-01

    There are many pathways for an air parcel to travel from the troposphere to the stratosphere, each of which takes different time. The distribution of all the possible transient times, i.e. the stratospheric age spectrum, contains important information on transport characteristics. However, it is computationally very expensive to compute seasonally varying age spectra, and previous studies have focused mainly on the annual mean properties of the age spectra. To date our knowledge of the seasonality of the stratospheric age spectra is very limited. In this study we investigate the seasonal variations of the stratospheric age spectra in the Goddard Earth Observing System Chemistry Climate Model (GEOSCCM). We introduce a method to significantly reduce the computational cost for calculating seasonally dependent age spectra. Our simulations show that stratospheric age spectra in GEOSCCM have strong seasonal cycles and the seasonal cycles change with latitude and height. In the lower stratosphere extratropics, the average transit times and the most probable transit times in the winter/early spring spectra are more than twice as old as those in the summer/early fall spectra. But the seasonal cycle in the subtropical lower stratosphere is nearly out of phase with that in the extratropics. In the middle and upper stratosphere, significant seasonal variations occur in the sUbtropics. The spectral shapes also show dramatic seasonal change, especially at high latitudes. These seasonal variations reflect the seasonal evolution of the slow Brewer-Dobson circulation (with timescale of years) and the fast isentropic mixing (with timescale of days to months).

  1. 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

  2. Disconnected aging: cerebral white matter integrity and age-related differences in cognition.

    PubMed

    Bennett, I J; Madden, D J

    2014-09-12

    Cognition arises as a result of coordinated processing among distributed brain regions and disruptions to communication within these neural networks can result in cognitive dysfunction. Cortical disconnection may thus contribute to the declines in some aspects of cognitive functioning observed in healthy aging. Diffusion tensor imaging (DTI) is ideally suited for the study of cortical disconnection as it provides indices of structural integrity within interconnected neural networks. The current review summarizes results of previous DTI aging research with the aim of identifying consistent patterns of age-related differences in white matter integrity, and of relationships between measures of white matter integrity and behavioral performance as a function of adult age. We outline a number of future directions that will broaden our current understanding of these brain-behavior relationships in aging. Specifically, future research should aim to (1) investigate multiple models of age-brain-behavior relationships; (2) determine the tract-specificity versus global effect of aging on white matter integrity; (3) assess the relative contribution of normal variation in white matter integrity versus white matter lesions to age-related differences in cognition; (4) improve the definition of specific aspects of cognitive functioning related to age-related differences in white matter integrity using information processing tasks; and (5) combine multiple imaging modalities (e.g., resting-state and task-related functional magnetic resonance imaging; fMRI) with DTI to clarify the role of cerebral white matter integrity in cognitive aging. PMID:24280637

  3. Age-related preferences and age weighting health benefits.

    PubMed

    Tsuchiya, A

    1999-01-01

    This paper deals with the relevance of age in the paradigm of quality adjusted life years (QALYs). The first section outlines two rationales for incorporating age weights into QALYs. One of them is based on efficiency concerns; and the other on equity concerns. Both of these are theoretical constructs. The main purpose of this paper is to examine the extent of published empirical support for such age weighting. The second section is a brief survey of nine empirical studies that elicited age-related preferences from the general public. Six of these quantified the strength of the preferences, and these are discussed in more detail in the third section. The analysis distinguishes three kinds of age-related preference: productivity ageism, utilitarian ageism and egalitarian ageism. The relationship between them and their relevance to the two different rationales for age weighting are then explored. It is concluded that, although there is strong prima facie evidence of public support for both types of age weighting, the empirical evidence to support any particular set of weights is at present weak. PMID:10048783

  4. Aging male bodies, health and the reproduction of age relations.

    PubMed

    Pietilä, Ilkka; Ojala, Hanna; King, Neal; Calasanti, Toni

    2013-08-01

    This article explores the ways in which a group of male factory workers uses bodies as bases for hierarchical categorization of men by age in their talk of mundane aspects of their lives. Analysis of interviews about health (4 focus groups and 5 personal interviews) with Finnish working-class men under 40 years old shows that they portray age groups to which they do not belong as careless, even irresponsible toward health and its maintenance. As they categorize youth and old people by age, they leave themselves unmarked by it, providing no vocabulary to describe their own group. Despite their tendency to distance themselves particularly from old people, they also distinguish among older men by familiarity, providing relatively nuanced accounts of their fathers' aging. We discuss the marking of age groups in terms of social inequality and talk of fathers in terms of intergenerational relations. Even family ties among men of diverse ages involve ageism, which familiarity serves both to mitigate and to make less visible. This article documents the maintenance of age inequality in everyday, mundane behavior. PMID:23849422

  5. Stratospheric age of air variations between 1600 and 2100

    NASA Astrophysics Data System (ADS)

    Muthers, S.; Kuchar, A.; Stenke, A.; Schmitt, J.; Anet, J. G.; Raible, C. C.; Stocker, T. F.

    2016-05-01

    The current understanding of preindustrial stratospheric age of air (AoA), its variability, and the potential natural forcing imprint on AoA is very limited. Here we assess the influence of natural and anthropogenic forcings on AoA using ensemble simulations for the period 1600 to 2100 and sensitivity simulations for different forcings. The results show that from 1900 to 2100, CO2 and ozone-depleting substances are the dominant drivers of AoA variability. With respect to natural forcings, volcanic eruptions cause the largest AoA variations on time scales of several years, reducing the age in the middle and upper stratosphere and increasing the age below. The effect of the solar forcing on AoA is small and dominated by multidecadal total solar irradiance variations, which correlate negatively with AoA. Additionally, a very weak positive relationship driven by ultraviolett variations is found, which is dominant for the 11 year cycle of solar variability.

  6. Age-Related White Matter Changes

    PubMed Central

    Xiong, Yun Yun; Mok, Vincent

    2011-01-01

    Age-related white matter changes (WMC) are considered manifestation of arteriolosclerotic small vessel disease and are related to age and vascular risk factors. Most recent studies have shown that WMC are associated with a host of poor outcomes, including cognitive impairment, dementia, urinary incontinence, gait disturbances, depression, and increased risk of stroke and death. Although the clinical relevance of WMC has been extensively studied, to date, only very few clinical trials have evaluated potential symptomatic or preventive treatments for WMC. In this paper, we reviewed the current understanding in the pathophysiology, epidemiology, clinical importance, chemical biomarkers, and treatments of age-related WMC. PMID:21876810

  7. Incentive relativity in middle aged rats.

    PubMed

    Justel, N; Mustaca, A; Boccia, M; Ruetti, E

    2014-01-24

    Response to a reinforcer is affected by prior experience with different reward values of that reward, a phenomenon known as incentive relativity. Two different procedures to study this phenomenon are the incentive downshift (ID) and the consummatory anticipatory negative contrast (cANC), the former is an emotional-cognitive protocol and the latter cognitive one. Aged rodents, as also well described in aged humans, exhibit alterations in cognitive functions. The main goal of this work was to evaluate the effect of age in the incentive' assessment using these two procedures. The results indicated that aged rats had an adequate assessment of the rewards but their performance is not completely comparable to that of young subjects. They recover faster from the ID and they had a cognitive impairment in the cANC. The results are discussed in relation to age-related changes in memory and emotion. PMID:24315974

  8. X-82 to Treat Age-related Macular Degeneration

    ClinicalTrials.gov

    2016-08-16

    Age-Related Macular Degeneration (AMD); Macular Degeneration; Exudative Age-related Macular Degeneration; AMD; Macular Degeneration, Age-related, 10; Eye Diseases; Retinal Degeneration; Retinal Diseases

  9. Health-and disease-related biomarkers in aging research.

    PubMed

    Thompson, Hilaire J; Voss, Joachim G

    2009-04-01

    This article focuses on a synthesis of knowledge about healthy aging research in human beings and then synthesized nurse-led research in gerontology and geriatrics that use biomarkers. Healthy aging research has attracted considerable attention in the biomedical and basic sciences within the context of four major areas: (a) genetic variations as an expression of successful or unsuccessful aging; (b) caloric restriction as an intervention to slow the progression of aging; (c) immunological aging; (d) neurobiology of the aging brain. A systematic review of the literature was performed to identify nurse-led geriatric-related biomarker research. Nurse researchers who have chosen to integrate biomarkers as part of their research studies have been working in six focal areas, which are reviewed: health promotion within risk populations, cancer, vascular disease, Alzheimer's disease, caregiving, and complementary therapies. The article provides a discussion of contributions to date, identifying existing gaps and future research opportunities. PMID:20077975

  10. Translational strategies in aging and age-related disease.

    PubMed

    Armanios, Mary; de Cabo, Rafael; Mannick, Joan; Partridge, Linda; van Deursen, Jan; Villeda, Saul

    2015-12-01

    Aging is a risk factor for several of the world's most prevalent diseases, including neurodegenerative disorders, cancer, cardiovascular disease and metabolic disease. Although our understanding of the molecular pathways that contribute to the aging process and age-related disease is progressing through the use of model organisms, how to apply this knowledge in the clinic is less clear. In September, Nature Medicine, in collaboration with the Volkswagen Foundation, hosted a conference at the beautiful Herrenhausen Palace in Hannover, Germany with the goal of broadening our understanding of the aging process and its meaning as a 'risk factor' in disease. Here, several of the speakers at that conference answer questions posed by Nature Medicine. PMID:26646495

  11. Inflammatory networks in ageing, age-related diseases and longevity.

    PubMed

    Vasto, Sonya; Candore, Giuseppina; Balistreri, Carmela Rita; Caruso, Marco; Colonna-Romano, Giuseppina; Grimaldi, Maria Paola; Listi, Florinda; Nuzzo, Domenico; Lio, Domenico; Caruso, Calogero

    2007-01-01

    Inflammation is considered a response set by the tissues in response to injury elicited by trauma or infection. It is a complex network of molecular and cellular interactions that facilitates a return to physiological homeostasis and tissue repair. The individual response against infection and trauma is also determined by gene variability. Ageing is accompanied by chronic low-grade inflammation state clearly showed by 2-4-fold increase in serum levels of inflammatory mediators. A wide range of factors has been claimed to contribute to this state; however, the most important role seems to be played by the chronic antigenic stress, which affects immune system thorough out life with a progressive activation of macrophages and related cells. This pro-inflammatory status, interacting with the genetic background, potentially triggers the onset of age-related inflammatory diseases as atherosclerosis. Thus, the analysis of polymorphisms of the genes that are key nodes of the natural immunity response might clarify the patho-physiology of age-related inflammatory diseases as atherosclerosis. On the other hand, centenarians are characterized by marked delay or escape from age-associated diseases that, on average, cause mortality at earlier ages. In addition, centenarian offspring have increased likelihood of surviving to 100 years and show a reduced prevalence of age-associated diseases, as cardiovascular disease (CVD) and less prevalence of cardiovascular risk factors. So, genes involved in CVD may play an opposite role in human longevity. Thus, the model of centenarians can be used to understand the role of these genes in successful and unsuccessful ageing. Accordingly, we report the results of several studies in which the frequencies of pro-inflammatory alleles were significantly higher in patients affected by infarction and lower in centenarians whereas age-related controls displayed intermediate values. These findings point to a strong relationship between the genetics

  12. Relative age effect in Japanese male athletes.

    PubMed

    Nakata, Hiroki; Sakamoto, Kiwako

    2011-10-01

    The present study investigated the relative age effect, a biased distribution of elite athletes' birthdates, in Japanese male athletes. Japan applies a unique annual-age grouping for sport and education, which is from April 1 to March 31 of the following year. A total of 4,318 male athletes was evaluated from 12 sports: baseball, soccer, basketball, volleyball, handball, golf, horse racing, rugby, American football, sumo, Ekiden (track and field in long distance), and badminton. They played in the top level of Japanese leagues for each sport in 2010. The distribution of the birth dates was examined in each sport and showed significant relative age effect in baseball, soccer, volleyball, Ekiden, basketball, sumo, and horse racing, but not in all sports. The findings suggest that although the school year in Japan starts on April 1, significant relative age effects are observed in some sporting events. PMID:22185072

  13. 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

  14. Gender Relations and Applied Research on Aging

    ERIC Educational Resources Information Center

    Calasanti, Toni

    2010-01-01

    As a concept in gerontology, gender appears as lists of traits learned through socialization when theorized at all. I argue for a framework that theorizes the intersections of relations of gender inequality with those of age. This framework holds that men and women gain resources and bear responsibilities, in relation to one another, by virtue of…

  15. Post-traumatic stress and age variation in amygdala volumes among youth exposed to trauma.

    PubMed

    Weems, Carl F; Klabunde, Megan; Russell, Justin D; Reiss, Allan L; Carrión, Victor G

    2015-12-01

    Theoretically, normal developmental variation in amygdala volumes may be altered under conditions of severe stress. The purpose of this article was to examine whether posttraumatic stress moderates the association between age and amygdala volumes in youth exposed to traumatic events who are experiencing symptoms of post-traumatic stress disorder (PTSD). Volumetric imaging was conducted on two groups of youth aged 9-17 years: 28 with exposure to trauma and PTSD symptoms (boys = 15, girls = 13) and 26 matched (age, IQ) comparison youth (Controls; boys = 12, girls = 14). There was a significant group by age interaction in predicting right amygdala volumes. A positive association between age and right amygdala volumes was observed, but only in PTSD youth. These associations with age remained when controlling for IQ, total brain volumes and sex. Moreover, older youth with PTSD symptoms had relatively larger right amygdala volumes than controls. Findings provide evidence that severe stress may influence age-related variation in amygdala volumes. Results further highlight the importance of utilizing age as an interactive variable in pediatric neuroimaging research, in so far as age may act as an important moderator of group differences. PMID:25964500

  16. Proinflammatory cytokines, aging, and age-related diseases.

    PubMed

    Michaud, Martin; Balardy, Laurent; Moulis, Guillaume; Gaudin, Clement; Peyrot, Caroline; Vellas, Bruno; Cesari, Matteo; Nourhashemi, Fati

    2013-12-01

    Inflammation is a physiological process that repairs tissues in response to endogenous or exogenous aggressions. Nevertheless, a chronic state of inflammation may have detrimental consequences. Aging is associated with increased levels of circulating cytokines and proinflammatory markers. Aged-related changes in the immune system, known as immunosenescence, and increased secretion of cytokines by adipose tissue, represent the major causes of chronic inflammation. This phenomenon is known as "inflamm-aging." High levels of interleukin (IL)-6, IL-1, tumor necrosis factor-α, and C-reactive protein are associated in the older subject with increased risk of morbidity and mortality. In particular, cohort studies have indicated TNF-α and IL-6 levels as markers of frailty. The low-grade inflammation characterizing the aging process notably concurs at the pathophysiological mechanisms underlying sarcopenia. In addition, proinflammatory cytokines (through a variety of mechanisms, such as platelet activation and endothelial activation) may play a major role in the risk of cardiovascular events. Dysregulation of the inflammatory pathway may also affect the central nervous system and be involved in the pathophysiological mechanisms of neurodegenerative disorders (eg, Alzheimer disease).The aim of the present review was to summarize different targets of the activity of proinflammatory cytokines implicated in the risk of pathological aging. PMID:23792036

  17. Relative Attribute SVM+ Learning for Age Estimation.

    PubMed

    Wang, Shengzheng; Tao, Dacheng; Yang, Jie

    2016-03-01

    When estimating age, human experts can provide privileged information that encodes the facial attributes of aging, such as smoothness, face shape, face acne, wrinkles, and bags under-eyes. In automatic age estimation, privileged information is unavailable to test images. To overcome this problem, we hypothesize that asymmetric information can be explored and exploited to improve the generalizability of the trained model. Using the learning using privileged information (LUPI) framework, we tested this hypothesis by carefully defining relative attributes for support vector machine (SVM+) to improve the performance of age estimation. We term this specific setting as relative attribute SVM+ (raSVM+), in which the privileged information enables separation of outliers from inliers at the training stage and effectively manipulates slack variables and age determination errors during model training, and thus guides the trained predictor toward a generalizable solution. Experimentally, the superiority of raSVM+ was confirmed by comparing it with state-of-the-art algorithms on the face and gesture recognition research network (FG-NET) and craniofacial longitudinal morphological face aging databases. raSVM+ is a promising development that improves age estimation, with the mean absolute error reaching 4.07 on FG-NET. PMID:25850101

  18. Middle-aged adults exhibit altered spatial variations in Achilles tendon wave speed

    PubMed Central

    Slane, Laura Chernak; DeWall, Ryan; Martin, Jack; Lee, Kenneth; Thelen, Darryl G.

    2016-01-01

    The purpose of this study was to investigate spatial variations in measured wave speed in the relaxed and stretched Achilles tendons of young and middle-aged adults. Wave speed was measured from the distal Achilles tendon, soleus aponeurosis, medial gastrocnemius aponeurosis and medial gastrocnemius muscle in healthy young (n = 15, aged 25 ± 4 years) and middle-aged (n = 10, aged 49 ± 4 years) adults in resting, dorsiflexed and plantarflexed postures. In both age groups, Achilles tendon wave speed decreased proximally, with the lowest wave speed measured in the gastrocnemius aponeurosis. Measured wave speed increased with passive dorsiflexion, reflecting the strain-stiffening behavior of tendons. There were no significant aging effects on wave speed in the free tendon or soleus aponeurosis. However, a significant, inverse relationship between gastrocnemius aponeurosis wave speed and age was observed in the dorsiflexed posture. We also observed significantly lower wave speeds in the gastrocnemius muscles of middle-aged adults when compared with young adults. These results suggest that Achilles tendon compliance increases in a distal-to-proximal pattern, with middle-aged adults exhibiting greater compliance in the distal gastrocnemius muscle and tendinous structures. An age-related change in the spatial variation in Achilles tendon compliance could affect localised tissue deformation patterns and injury potential within the triceps surae muscle-tendon units. PMID:26020294

  19. Thunderstorm related variations in stratospheric conductivity measurements

    NASA Technical Reports Server (NTRS)

    Hu, Hua; Holzworth, Robert H.; Li, Ya QI

    1989-01-01

    The vector electric field and polar conductivities were measured by zero-pressure balloon-borne payloads launched from Wallops Island, Virgina during the summers of 1987 and 1988. Data were collected over thunderstorms (or electrified clouds) during 6-hour flights at altitudes near 30 km. The vector electric field measurements were made with the double Langmuir probe high-impedance method, and the direct conductivity measurements were obtained with the relaxation technique. Evidence is presented for conductivity variations over thunderstorms (or electrified clouds). It is found that both positive and negative polar conductivity data do show variations of up to a factor of 2 from ambient values associated with the disturbed periods. Some ideas for possible physical mechanisms which may be responsible for the conductivity variations over thunderstorms are also discussed in this paper.

  20. Pharmacogenetics and age-related macular degeneration.

    PubMed

    Schwartz, Stephen G; Brantley, Milam A

    2011-01-01

    Pharmacogenetics seeks to explain interpatient variability in response to medications by investigating genotype-phenotype correlations. There is a small but growing body of data regarding the pharmacogenetics of both nonexudative and exudative age-related macular degeneration. Most reported data concern polymorphisms in the complement factor H and age-related maculopathy susceptibility 2 genes. At this time, the data are not consistent and no definite conclusions may be drawn. As clinical trials data continue to accumulate, these relationships may become more apparent. PMID:22046503

  1. Age-related hair pigment loss.

    PubMed

    Tobin, Desmond J

    2015-01-01

    Humans are social animals that communicate disproportionately via potent genetic signals imbued in the skin and hair, including racial, ethnic, health, gender, and age status. For the vast majority of us, age-related hair pigment loss becomes the inescapable signal of our disappearing youth. The hair follicle (HF) pigmentary unit is a wonderful tissue for studying mechanisms generally regulating aging, often before this becomes evident elsewhere in the body. Given that follicular melanocytes (unlike those in the epidermis) are regulated by the hair growth cycle, this cycle is likely to impact the process of aging in the HF pigmentary unit. The formal identification of melanocyte stem cells in the mouse skin has spurred a flurry of reports on the potential involvement of melanocyte stem cell depletion in hair graying (i.e., canities). Caution is recommended, however, against simple extrapolation of murine data to humans. Regardless, hair graying in both species is likely to involve an age-related imbalance in the tissue's oxidative stress handling that will impact not only melanogenesis but also melanocyte stem cell and melanocyte homeostasis and survival. There is some emerging evidence that the HF pigmentary unit may have regenerative potential, even after it has begun to produce white hair fibers. It may therefore be feasible to develop strategies to modulate some aging-associated changes to maintain melanin production for longer. PMID:26370651

  2. Variations in Human Capital Investment Activity by Age.

    ERIC Educational Resources Information Center

    Simpson, Patricia A.; Greller, Martin M.; Stroh, Linda K.

    2002-01-01

    Late-career workers (ages 50-65) were more likely to participate in credentialing programs, targeted job-related courses, and on-the-job computer training than younger adults and received similar employer support. However, participation might be a consequence of support received. Human capital investment thus is more complex than conventional…

  3. Phylogeny of Aging and Related Phenoptotic Phenomena.

    PubMed

    Libertini, G

    2015-12-01

    The interpretation of aging as adaptive, i.e. as a phenomenon genetically determined and modulated, and with an evolutionary advantage, implies that aging, as any physiologic mechanism, must have phylogenetic connections with similar phenomena. This review tries to find the phylogenetic connections between vertebrate aging and some related phenomena in other species, especially within those phenomena defined as phenoptotic, i.e. involving the death of one or more individuals for the benefit of other individuals. In particular, the aim of the work is to highlight and analyze similarities and connections, in the mechanisms and in the evolutionary causes, between: (i) proapoptosis in prokaryotes and apoptosis in unicellular eukaryotes; (ii) apoptosis in unicellular and multicellular eukaryotes; (iii) aging in yeast and in vertebrates; and (iv) the critical importance of the DNA subtelomeric segment in unicellular and multicellular eukaryotes. In short, there is strong evidence that vertebrate aging has clear similarities and connections with phenomena present in organisms with simpler organization. These phylogenetic connections are a necessary element for the sustainability of the thesis of aging explained as an adaptive phenomenon, and, on the contrary, are incompatible with the opposite view of aging as being due to the accumulation of random damages of various kinds. PMID:26638678

  4. [Age-related changes of sensory system].

    PubMed

    Iwamoto, Toshihiko; Hanyu, Haruo; Umahara, Takahiko

    2013-10-01

    Pathological processes usually superimpose on physiological aging even in the sensory system including visual, hearing, olfactory, taste and somatosensory functions. Representative changes of age-related changes are presbyopia, cataracts, and presbyacusis. Reduced sense of smell is seen in normal aging, but the prominent reduction detected by the odor stick identification test is noticed especially in early stage of Alzheimer or Parkinson disease. Reduced sense of taste is well-known especially in salty sense, while the changes of sweet, bitter, and sour tastes are different among individuals. Finally, deep sensation of vibration and proprioception is decreased with age as well as superficial sensation (touch, temperature, pain). As a result, impaired sensory system could induce deterioration of the activities of daily living and quality of life in the elderly. PMID:24261198

  5. Work related injury among aging women.

    PubMed

    Harrison, Tracie; Legarde, Brittany; Kim, Sunhun; Walker, Janiece; Blozis, Shelley; Umberson, Debra

    2013-02-01

    This article reports the experiences of women aged 55 to 75 with mobility impairments who attributed aspects of their limitations to workplace injuries and provides insight into worker's compensation policies. The study sample includes Mexican American (MA) and non-Hispanic White (NHW) women aged 55 to 75 who participated in a 4-year ethnographic study of disablement. Ninety-two of the 122 participants in the study attributed aspects of their functional limitations to employment, and their experiences were analyzed using data from 354 meetings. Using Lipscomb and colleagues' conceptual model of work and health disparities, the women's experiences were grouped into three categories according to type of injury, assistance gained, and the consequences of a workplace injury; the results have broad implications for policies that influence aging outcomes. Workplace injuries causing permanent functional limitations compound the effects of age and gender on employment outcomes. Policies addressing health disparities should consider work related influences. PMID:23528432

  6. Work Related Injury among Aging Women

    PubMed Central

    LeGarde, Brittany; Kim, SungHun; Walker, Janiece; Blozis, Shelley; Umberson, Debra

    2013-01-01

    This article reports the experiences of women age 55 to 75 with mobility impairments who attributed aspects of their limitations to workplace injuries and provides insight into worker’s compensation policies. The study sample includes Mexican American and non-Hispanic White women ages 55–75 who participated in a 4-year ethnographic study of disablement. Ninety-two of the 122 participants in the study attributed aspects of their functional limitations to employment, and their experiences were analyzed using data from 354 meetings. Using Lipscomb and colleagues’ conceptual model of work and health disparities, the women’s experiences were grouped into three categories according to type of injury, assistance gained, and the consequences of a workplace injury; the results have broad implications for policies that influence aging outcomes. Workplace injuries causing permanent functional limitations compound the effects of age and gender on employment outcomes. Policies addressing health disparities should consider work related influences. PMID:23528432

  7. Spatial and temporal variations in the age structure of Arctic sea ice

    USGS Publications Warehouse

    Belchansky, G.I.; Douglas, D.C.; Platonov, N.G.

    2005-01-01

    Spatial and temporal variations in the age structure of Arctic sea ice are investigated using a new reverse chronology algorithm that tracks ice-covered pixels to their location and date of origin based on ice motion and concentration data. The Beaufort Gyre tends to harbor the oldest (>10 years old) sea ice in the western Arctic while direct ice advection pathways toward the Transpolar Drift Stream maintain relatively young (10 years old (10+ year age class) were observed during 1989-2003. Since the mid-1990s, losses to the 10+ year age class lacked compensation by recruitment due to a prior depletion of all mature (6-10 year) age classes. Survival of the 1994 and 1996-1998 sea ice generations reestablished most mature age classes, and thereby the potential to increase extent of the 10+ year age class during the mid-2000s.

  8. Morphometric analysis of variation in the ribs with age and sex.

    PubMed

    Weaver, Ashley A; Schoell, Samantha L; Stitzel, Joel D

    2014-08-01

    Rib cage morphology changes with age and sex are expected to affect thoracic injury mechanisms and tolerance, particularly for vulnerable populations such as pediatrics and the elderly. The size and shape variation of the external geometry of the ribs was characterized for males and females aged 0-100 years. Computed tomography (CT) scans from 339 subjects were analyzed to collect between 2700 and 10 400 homologous landmarks from each rib. Rib landmarks were analyzed using the geometric morphometric technique known as Procrustes superimposition. Age- and sex-specific functions of 3D rib morphology were produced representing the combined size and shape variation and the isolated shape variation. Statistically significant changes in the size and shape variation (P < 0.0001) and shape variation (P < 0.0053) of all 24 ribs were found to occur with age in males and females. Rib geometry, location, and orientation varied according to the rib level. From birth through adolescence, the rib cage experienced an increase in size, a decrease in thoracic kyphosis, and inferior rotation of the ribs relative to the spine within the sagittal plane. From young adulthood into elderly age, the rib cage experienced increased thoracic kyphosis and superior rotation of the ribs relative to the spine within the sagittal plane. The increased roundedness of the rib cage and horizontal angling of the ribs relative to the spine with age influences the biomechanical response of the thorax. With the plane of the rib oriented more horizontally, loading applied in the anterior-posterior direction will result in increased deformation within the plane of the rib and an increased risk for rib fractures. Thus, morphological changes may be a contributing factor to the increased incidence of rib fractures in the elderly. The morphological functions derived in this study capture substantially more information on thoracic skeleton morphology variation with age and sex than is currently available

  9. Morphometric analysis of variation in the ribs with age and sex

    PubMed Central

    Weaver, Ashley A; Schoell, Samantha L; Stitzel, Joel D

    2014-01-01

    Rib cage morphology changes with age and sex are expected to affect thoracic injury mechanisms and tolerance, particularly for vulnerable populations such as pediatrics and the elderly. The size and shape variation of the external geometry of the ribs was characterized for males and females aged 0–100 years. Computed tomography (CT) scans from 339 subjects were analyzed to collect between 2700 and 10 400 homologous landmarks from each rib. Rib landmarks were analyzed using the geometric morphometric technique known as Procrustes superimposition. Age- and sex-specific functions of 3D rib morphology were produced representing the combined size and shape variation and the isolated shape variation. Statistically significant changes in the size and shape variation (P < 0.0001) and shape variation (P < 0.0053) of all 24 ribs were found to occur with age in males and females. Rib geometry, location, and orientation varied according to the rib level. From birth through adolescence, the rib cage experienced an increase in size, a decrease in thoracic kyphosis, and inferior rotation of the ribs relative to the spine within the sagittal plane. From young adulthood into elderly age, the rib cage experienced increased thoracic kyphosis and superior rotation of the ribs relative to the spine within the sagittal plane. The increased roundedness of the rib cage and horizontal angling of the ribs relative to the spine with age influences the biomechanical response of the thorax. With the plane of the rib oriented more horizontally, loading applied in the anterior-posterior direction will result in increased deformation within the plane of the rib and an increased risk for rib fractures. Thus, morphological changes may be a contributing factor to the increased incidence of rib fractures in the elderly. The morphological functions derived in this study capture substantially more information on thoracic skeleton morphology variation with age and sex than is currently available in

  10. Driving and Age-Related Macular Degeneration

    ERIC Educational Resources Information Center

    Owsley, Cynthia; McGwin, Gerald, Jr.

    2008-01-01

    This article reviews the research literature on driving and age-related macular degeneration, which is motivated by the link between driving and the quality of life of older adults and their increased collision rate. It addresses the risk of crashes, driving performance, driving difficulty, self-regulation, and interventions to enhance, safety,…

  11. Depression in Age-Related Macular Degeneration

    ERIC Educational Resources Information Center

    Casten, Robin; Rovner, Barry

    2008-01-01

    Age-related macular degeneration (AMD) is a major cause of disability in the elderly, substantially degrades the quality of their lives, and is a risk factor for depression. Rates of depression in AMD are substantially greater than those found in the general population of older people, and are on par with those of other chronic and disabling…

  12. Driving and Age-Related Macular Degeneration

    PubMed Central

    Owsley, Cynthia; McGwin, Gerald

    2009-01-01

    This article reviews the research literature on driving and age-related macular degeneration, which is motivated by the link between driving and the quality of life of older adults and their increased collision rate. It addresses the risk of crashes, driving performance, driving difficulty, self-regulation, and interventions to enhance, safety, and considers directions for future research. PMID:20046818

  13. Neuromuscular contributions to age-related weakness

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Age-related physiological change of neuromuscular function is not a linear process and is likely influenced by various biological and behavioral factors (e.g., genetics, nutrition, physical activity level, comorbidities, etc.). These factors contribute to heterogeneity among older adults, which chal...

  14. Genetic and Environmental Variation in Lung Function Drives Subsequent Variation in Aging of Fluid Intelligence

    PubMed Central

    Reynolds, Chandra A.; Emery, Charles F.; Pedersen, Nancy L.

    2013-01-01

    Longitudinal studies document an association of pulmonary function with cognitive function in middle-aged and older adults. Previous analyses have identified a genetic contribution to the relationship between pulmonary function with fluid intelligence. The goal of the current analysis was to apply the biometric dual change score model to consider the possibility of temporal dynamics underlying the genetic covariance between aging trajectories for pulmonary function and fluid intelligence. Longitudinal data from the Swedish Adoption/Twin Study of Aging were available from 808 twins ranging in age from 50 to 88 years at the first wave. Participants completed up to six assessments covering a 19-year period. Measures at each assessment included spatial and speed factors and pulmonary function. Model-fitting indicated that genetic variance for FEV1 was a leading indicator of variation in age changes for spatial and speed factors. Thus, these data indicate a genetic component to the directional relationship from decreased pulmonary function to decreased function of fluid intelligence. PMID:23760789

  15. Statistical physics of age related macular degeneration

    NASA Astrophysics Data System (ADS)

    Family, Fereydoon; Mazzitello, K. I.; Arizmendi, C. M.; Grossniklaus, H. E.

    Age-related macular degeneration (AMD) is the leading cause of blindness beyond the age of 50 years. The most common pathogenic mechanism that leads to AMD is choroidal neovascularization (CNV). CNV is produced by accumulation of residual material caused by aging of retinal pigment epithelium cells (RPE). The RPE is a phagocytic system that is essential for renewal of photoreceptors (rods and cones). With time, incompletely degraded membrane material builds up in the form of lipofuscin. Lipofuscin is made of free-radical-damaged protein and fat, which forms not only in AMD, but also Alzheimer disease and Parkinson disease. The study of lipofuscin formation and growth is important, because of their association with cellular aging. We introduce a model of non-equilibrium cluster growth and aggregation that we have developed for studying the formation and growth of lipofuscin in the aging RPE. Our results agree with a linear growth of the number of lipofuscin granules with age. We apply the dynamic scaling approach to our model and find excellent data collapse for the cluster size distribution. An unusual feature of our model is that while small particles are removed from the RPE the larger ones become fixed and grow by aggregation.

  16. The age of astronomy-related organizations

    NASA Astrophysics Data System (ADS)

    Heck, A.

    1999-03-01

    The age of currently active astronomy-related organizations is investigated from comprehensive and up-to-date samples. Results for professional institutions, associations, planetariums, and public observatories are commented, as well as specific distributions for astronomy-related publishers and software producers. Some events had a clear impact on the rate of foundation of astronomy-related organizations, such as World War I and II, the beginning of space exploration and the landing of man on the Moon, but not all of them affected in the same way Western Europe and North America. It is still premature to assess the impact of the end of the Cold War. A category such as the software producers would of course not exist nor prosper without the advent of the computer age and the subsequent electronic networking of the planet. Other aspects are discussed in the paper.

  17. [Aged woman's vulnerability related to AIDS].

    PubMed

    Silva, Carla Marins; Lopes, Fernanda Maria do Valle Martins; Vargens, Octavio Muniz da Costa

    2010-09-01

    This article is a systhematic literature review including the period from 1994 to 2009, whose objective was to discuss the aged woman's vulnerability in relation to Acquired Imunodeficiency Syndrome (Aids). The search for scientific texts was accomplished in the following databases: Biblioteca Virtual em Saúde, Scientific Eletronic Library Online (SciELO), Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS) and Medical Literature Analysis and Retrieval System Online (MEDLINE). The descriptors used were vulnerability, woman and Aids. Eighteen texts were analyzed, including articles in scientific journals, thesis and dissertations. As a conclusion, it was noted that aged women and vulnerability to Aids are directly related, through gender characteristics including submission and that were built historical and socially. We consider as fundamental the development of studies which may generate publications accessible to women, in order to help them see themselves as persons vulnerable to Aids contagion just for being women. PMID:21574329

  18. The Correlation of Age and Postoperative Visual Acuity for Age-Related Cataract

    PubMed Central

    Li, Xiaochun; Cao, Xiaoguang; Hou, Xianru; Bao, Yongzhen

    2016-01-01

    Purpose. Clinically, what is the best time for age-related cataract (ARC) patients to receive surgeries and get the most benefits is important. We explored the relationship between age and presenting postoperative visual acuity (POVA) in patients from rural China. Methods. Three Lifeline Express Hospital Eye-Train missions of Peking University People's Hospital were chosen. At the first day after surgery, 3452 ARC eyes with the presenting POVA ≥ 6/60 were enrolled. The relationship between age and POVA was analyzed statistically. Results. In these three missions, there were more female patients than males; the ratio of females to males was 1.71. The average age of females was older than males. Overall, the percentages of patients with good visual outcomes (≥6/18) were significantly decreased with aging. Different regions had variations, but the trends were the same. There was weak linear correlation between age and POVA. The correlations of females were stronger than males in Yuncheng and Sanmenxia and weaker than males in Zhoukou. Conclusion. The good visual outcomes of presenting POVA were significantly decreased with aging and there were weak linear correlations between age and POVA in rural China. The linear correlation might be influenced by the difference of gender and region. PMID:26881225

  19. Physics of Age Related Macular Degeneration

    NASA Astrophysics Data System (ADS)

    Family, Fereydoon

    2009-11-01

    Age-related macular degeneration (AMD) is the leading cause of blindness beyond the age of 50 years. The most common pathogenic mechanism that leads to AMD is choroidal neovascularization (CNV). CNV is produced by accumulation of residual material caused by aging of retinal pigment epithelium cells (RPE). The RPE is a phagocytic system that is essential for renewal of photoreceptors (rods and cones). With time, incompletely degraded membrane material builds up in the form of lipofuscin. Lipofuscin is made of free-radical-damaged protein and fat, which forms not only in AMD, but also Alzheimer's disease, and Parkinson's disease. The study of lipofuscin formation and growth is important, because of their association with cellular aging. In this talk I will discuss a model of non-equilibrium cluster growth that we have developed for studying the formation and growth of lipofuscin in AMD [K.I. Mazzitello, C.M. Arizmendi, Fereydoon Family, H. E. Grossniklaus, Physical Review E (2009)]. I will also present an overview of our theoretical and computational efforts in modeling some other aspects of the physics of AMD, including CNV and the breakdown of Bruch's membrane [Ongoing collaboration with Abbas Shirinifard and James A. Glazier, Biocomplexity Institute and Department of Physics, Indiana University, Y. Jiang, Los Alamos, and Hans E. Grossniklaus, Department of Ophthalmology, Emory University].

  20. Age-related crosslink in skin collagen

    SciTech Connect

    Yamauchi, M.; Mechanic, G.

    1986-05-01

    A stable crosslinking amino acid was isolated from mature bovine skin collagen and its structure was identified as histidinohydroxylysinonorleucine (HHL) using fast atom bombardment mass spectrometry and /sup 1/H, /sup 13/C-NMR. This newly identified crosslink has a linkage between C-2 histidine and C-6 of lysine in the latter's portion of hydroxylysinonorleucine. Quantitative studies using various aged samples of cow and human skin collagen indicated that this acid-heat stable nonreducible compound was the major age-related crosslink. In case of cow skin collagen, for example, during early embryonic development (3 and 5 month old embryos) the content of HHL stayed less than 0.01 residue/mole of collagen, however from the middle of gestation period (7 month old embryo) through the maturation stage it showed rapid increase with age and reached approximately 0.5 residues/mole of collagen in the 3 year old animal. Small increments (up to 0.65 res/mole of collagen) were observed in the 9 year old cow. The amounts of the crosslink unlike pyridinoline do not decrease with aging. Similar patterns were observed in human skin collagen.

  1. Age-related differences in arithmetic strategy sequential effects.

    PubMed

    Lemaire, Patrick

    2016-03-01

    In this article, I review a series of new findings concerning how age-related changes in strategic variations are modulated by sequential effects. Sequential effects refer to how strategy selection and strategy execution on current problems are influenced by which strategy is used on immediately preceding problems. Two sequential effects during strategy selection (i.e., strategy revisions and strategy perseverations) and during strategy execution (i.e., strategy switch costs and modulations of poorer strategy effects) are presented. I also discuss how these effects change with age during adulthood. These phenomena are important, as they shed light on arithmetic processes and how these processes change with age during adulthood. In particular, they speak to the role of executive control while participants select and execute arithmetic strategies. Finally, I discuss the implications of sequential effects for theories of strategies and of arithmetic. (PsycINFO Database Record PMID:26372058

  2. Risk Factors for Age-Related Maculopathy

    PubMed Central

    Connell, Paul P.; Keane, Pearse A.; O'Neill, Evelyn C.; Altaie, Rasha W.; Loane, Edward; Neelam, Kumari; Nolan, John M.; Beatty, Stephen

    2009-01-01

    Age-related maculopathy (ARM) is the leading cause of blindness in the elderly. Although beneficial therapeutic strategies have recently begun to emerge, much remains unclear regarding the etiopathogenesis of this disorder. Epidemiologic studies have enhanced our understanding of ARM, but the data, often conflicting, has led to difficulties with drawing firm conclusions with respect to risk for this condition. As a consequence, we saw a need to assimilate the published findings with respect to risk factors for ARM, through a review of the literature appraising results from published cross-sectional studies, prospective cohort studies, case series, and case control studies investigating risk for this condition. Our review shows that, to date, and across a spectrum of epidemiologic study designs, only age, cigarette smoking, and family history of ARM have been consistently demonstrated to represent risk for this condition. In addition, genetic studies have recently implicated many genes in the pathogenesis of age-related maculopathy, including Complement Factor H, PLEKHA 1, and LOC387715/HTRA1, demonstrating that environmental and genetic factors are important for the development of ARM suggesting that gene-environment interaction plays an important role in the pathogenesis of this condition. PMID:20339564

  3. Communication variations related to leader personality

    NASA Technical Reports Server (NTRS)

    Kanki, Barbara G.; Palmer, Mark T.; Veinott, Elizabeth S.

    1991-01-01

    While communication and captain personality type have been separately shown to relate to overall crew performance, this study attempts to establish a link between communication and personality among 12 crews whose captains represent three pre-selected personality profiles (IE+, I-, Ec-). Results from analyzing transcribed speech from one leg of a full-mission simulation study, so far indicate several discriminating patterns involving ratios of total initiating speech (captain to crew members); in particular commands, questions and observations.

  4. GENETICS OF HUMAN AGE RELATED DISORDERS.

    PubMed

    Srivastava, I; Thukral, N; Hasija, Y

    2015-01-01

    Aging is an inevitable biological phenomenon. The incidence of age related disorders (ARDs) such as cardiovascular diseases, cancer, arthritis, dementia, osteoporosis, diabetes, neurodegenerative diseases increase rapidly with aging. ARDs are becoming a key social and economic trouble for the world's elderly population (above 60 years), which is expected to reach 2 billion by 2050. Advancement in understanding of genetic associations, particularly through genome wide association studies (GWAS), has revealed a substantial contribution of genes to human aging and ARDs. In this review, we have focused on the recent understanding of the extent to which genetic predisposition may influence the aging process. Further analysis of the genetic association studies through pathway analysis several genes associated with multiple ARDs have been highlighted such as apolipoprotein E (APOE), brain-derived neurotrophic factor (BDNF), cadherin 13 (CDH13), CDK5 regulatory subunit associated protein 1 (CDKAL-1), methylenetetrahydrofolate reductase (MTHFR), disrupted in schizophrenia 1 (DISC1), nitric oxide synthase 3 (NOS3), paraoxonase 1 (PON1), indicating that these genes could play a pivotal role in ARD causation. These genes were found to be significantly enriched in Jak-STAT signalling pathway, asthma and allograft rejection. Further, interleukin-6 (IL-6), insulin (INS), vascular endothelial growth factor A (VEGFA), estrogen receptor1 (ESR1), transforming growth factor, beta 1(TGFB1) and calmodulin 1 (CALM1) were found to be highly interconnected in network analysis. We believe that extensive research on the presence of common genetic variants among various ARDs may facilitate scientists to understand the biology behind ARDs causation. PMID:26856084

  5. Age and seasonal-dependent variations in the biochemical composition of boar semen.

    PubMed

    Fraser, L; Strzeżek, J; Filipowicz, K; Mogielnicka-Brzozowska, M; Zasiadczyk, L

    2016-08-01

    This study investigated the effect of age- and seasonal-related variations in the composition of boar semen over a 3-year period. At the onset of 8 months of age, ejaculates were collected from four boars and allocated into three groups: 8 to 18, 19 to 30, and 31 to 42 months and were divided into two seasonal periods: autumn-winter and spring-summer. Boar variability had a significant effect on most of the analyzed semen parameters. Significantly, higher ejaculate volumes were observed in the boars older than 18 months of age during the autumn-winter period. Sperm concentration was higher in boars less than the age of 18 months of age, whereas the total sperm numbers were significantly higher during the autumn-winter period, regardless of the age group. Seasonal effects in sperm motility were more marked in boars at the age of 19 to 30 months, being significantly higher during the autumn-winter period. The proportions of spermatozoa with intact, normal apical ridge acrosome, and osmotically tolerant acrosomal membranes were markedly higher in boars at the age of 19 to 30 months during the autumn-winter period. Spermatozoa harvested during the spring-summer period were more susceptible to lipid peroxidation, irrespective of the age group. Significantly, higher levels of protein content and concentrations of nonthiol-containing antioxidant components of the seminal plasma (SP) were detected in boars less than 18 months of age during the autumn-winter period. Seasonal effects on the pH and proteinase inhibitory activity in the SP were more marked in boars less than 18 months of age, whereas alkaline phosphatase activity was greater in boars at the age of 19 to 30 months during the autumn-winter period. Substantial amounts of the thiol-containing antioxidants of the SP were detected in boars older than 18 months of age during the spring-summer period. Neither osmolality nor total antioxidant status was affected by differences in the seasonal periods or age

  6. Variation of Ginsenosides in Ginseng of Different Ages.

    PubMed

    He, Jian-Ming; Zhang, Yi-Zhen; Luo, Jian-Ping; Zhang, Wen-Ju; Mu, Qing

    2016-06-01

    Panax ginseng has been used in traditional oriental medicine for thousands of years. Ginsenosides, the major chemical components of the roots, are considered to be responsible for the medicinal properties of ginseng. Ginsenosides increase with the age of ginseng root in general knowledge, and in this study the content of ginsenosides in ginseng of different ages was quantified. Separation and determination of eight main ginsenosides, Rg1, Re, Rb1, Rc, Rg2, Rb2, Rb3 and Rd, was performed by high performance liquid chromatography with UV detection at 203 nm. The content of Rg1, Re, Rb1, Rc, Rg2 and Rd increased from 5 to 16-year-old ginseng and then decreased, while Rb2 and Rb3 increased in the range of 5-12 years, but then slowly decreased. However, the total eight ginsenosides in 16 year old ginseng had a higher content than that in any other from 5-18 years old. As a result, the content of ginsenosides and total ginsenosides was not positively related to age from 5-18 years, which is not in full agreement with the general knowledge of ginseng. Thus, this study suggests that the older wild ginseng may not result in better medicinal ginseng for herbal medicines. PMID:27534105

  7. Age-related macular degeneration: choroidal ischaemia?

    PubMed Central

    Coleman, D Jackson; Silverman, Ronald H; Rondeau, Mark J; Lloyd, Harriet O; Khanifar, Aziz A; Chan, R V Paul

    2013-01-01

    Aim Our aim is to use ultrasound to non-invasively detect differences in choroidal microarchitecture possibly related to ischaemia among normal eyes and those with wet and dry age-related macular degeneration (AMD). Design Prospective case series of subjects with dry AMD, wet AMD and age-matched controls. Methods Digitised 20 MHz B-scan radiofrequency ultrasound data of the region of the macula were segmented to extract the signal from the retina and choroid. This signal was processed by a wavelet transform, and statistical modelling was applied to the wavelet coefficients to examine differences among dry, wet and non-AMD eyes. Receiver operating characteristic (ROC) analysis was used to evaluate a multivariate classifier. Results In the 69 eyes of 52 patients, 18 did not have AMD, 23 had dry AMD and 28 had wet AMD. Multivariate models showed statistically significant differences between groups. Multiclass ROC analysis of the best model showed an excellent volume-under-curve of 0.892±0.17. The classifier is consistent with ischaemia in dry AMD. Conclusions Wavelet augmented ultrasound is sensitive to the organisational elements of choroidal microarchitecture relating to scatter and fluid tissue boundaries such as seen in ischaemia and inflammation, allowing statistically significant differentiation of dry, wet and non-AMD eyes. This study further supports the association of ischaemia with dry AMD and provides a rationale for treating dry AMD with pharmacological agents to increase choroidal perfusion. ClinicalTrials.gov registration NCT00277784. PMID:23740965

  8. Gender relations and applied research on aging.

    PubMed

    Calasanti, Toni

    2010-12-01

    As a concept in gerontology, gender appears as lists of traits learned through socialization when theorized at all. I argue for a framework that theorizes the intersections of relations of gender inequality with those of age. This framework holds that men and women gain resources and bear responsibilities, in relation to one another, by virtue of mundane categorization into naturalized stratified groups. Current research shows that this approach allows explanation of gender differences, which appear in many reports but which usually go untheorized, as responses to social inequality. I illustrate applications to research and practice in relation to three areas of old age experiences: financial security, spousal care work, and health. Throughout, I discuss implications of focusing on inequality to enhance our abilities to engage in effective research, practice, and policy for older people, women and men alike. For instance, an understanding of the gender division of labor and workplace discrimination makes clear that financial status in later life cannot be reduced to individual choices concerning paid labor or retirement planning. And understanding that people orient their behaviors to gender ideals allows us to see that men and women perform spousal care in similar and different ways that require varied responses from practitioners; it also reveals contexts in which men engage in positive health behaviors. Finally, I argue that gerontologists interested in facilitating favorable outcomes for old people should consider research and practice that would disrupt, not reinforce, the bases of gender inequalities in later life. PMID:20956798

  9. Age-related eye disease and gender.

    PubMed

    Zetterberg, Madeleine

    2016-01-01

    Worldwide, the prevalence of moderate to severe visual impairment and blindness is 285 millions, with 65% of visually impaired and 82% of all blind people being 50 years and older. Meta-analyses have shown that two out of three blind people are women, a gender discrepancy that holds true for both developed and developing countries. Cataract accounts for more than half of all blindness globally and gender inequity in access to cataract surgery is the major cause of the higher prevalence of blindness in women. In addition to gender differences in cataract surgical coverage, population-based studies on the prevalence of lens opacities indicate that women have a higher risk of developing cataract. Laboratory as well as epidemiologic studies suggest that estrogen may confer antioxidative protection against cataractogenesis, but the withdrawal effect of estrogen in menopause leads to increased risk of cataract in women. For the other major age-related eye diseases; glaucoma, age-related macular degeneration (AMD) and diabetic retinopathy, data are inconclusive. Due to anatomic factors, angle closure glaucoma is more common in women, whereas the dominating glaucoma type; primary open-angle glaucoma (POAG), is more prevalent in men. Diabetic retinopathy also has a male predominance and vascular/circulatory factors have been implied both in diabetic retinopathy and in POAG. For AMD, data on gender differences are conflicting although some studies indicate increased prevalence of drusen and neovascular AMD in women. To conclude, both biologic and socioeconomic factors must be considered when investigating causes of gender differences in the prevalence of age-related eye disease. PMID:26508081

  10. Historical variation in young adult binge drinking trajectories and its link to historical variation in social roles and minimum legal drinking age.

    PubMed

    Jager, Justin; Keyes, Katherine M; Schulenberg, John E

    2015-07-01

    This study examines historical variation in age 18 to 26 binge drinking trajectories, focusing on differences in both levels of use and rates of change (growth) across cohorts of young adults over 3 decades. As part of the national Monitoring the Future Study, over 64,000 youths from the high school classes of 1976 to 2004 were surveyed at biennial intervals between ages 18 and 26. We found that, relative to past cohorts, recent cohorts both enter the 18 to 26 age band engaging in lower levels and exit the 18 to 26 age band engaging in higher levels of binge drinking. The reason for this reversal is that, relative to past cohorts, binge drinking among recent cohorts accelerates more quickly across ages 18 to 22 and decelerates more slowly across ages 22 to 26. Moreover, we found that historical increases in minimum legal drinking age account for a portion of the historical decline in age 18 level, whereas historical variation in social role acquisition (e.g., marriage, parenthood, and employment) accounts for a portion of the historical acceleration in age 18 to 22 growth. We also found that historical variation in the age 18 to 22 and age 22 to 26 growth rates was strongly and positively connected, suggesting common mechanism(s) underlie historical variation of both growth rates. Findings were generally consistent across gender and indicate that historical time is an important source of individual differences in young adult binge drinking trajectories. Beyond binge drinking, historical time may also inform the developmental course of other young adult risk behaviors, highlighting the interplay of epidemiology and etiology. PMID:26010381

  11. Relative age effect: implications for effective practice.

    PubMed

    Andronikos, Georgios; Elumaro, Adeboye Israel; Westbury, Tony; Martindale, Russell J J

    2016-06-01

    Physical and psychological differences related to birthdate amongst athletes of the same selection year have been characterised as the "relative age effects" (RAEs). RAEs have been identified in a variety of sports, both at youth and adult level, and are linked with dropout of athletes and a reduction of the talent pool. This study examined the existence, mechanisms and possible solutions to RAEs using qualitative methodology. Seven experts in the field of talent identification and development were interviewed. Inductive analysis of the data showed that, while there was mixed evidence for the existence of RAEs across sports, the eradication of RAEs was attributed to controllable features of the development environment. The factors reported included the structure of "categories" used to group athletes within the sport (e.g. age, weight, size, skills), recognition and prioritisation of long-term development over "short term win focus." Education of relevant parties (e.g. coaches, scouts, clubs) about RAEs and the nature of "talent" within a long-term context was suggested, along with careful consideration of the structure of the development environment (e.g. delayed selection, provision for late developers, focus on skills not results, use of challenge). Implications for research and practice are discussed. PMID:26417709

  12. Variations of CT-Based Trunk Muscle Attenuation by Age, Sex, and Specific Muscle

    PubMed Central

    Anderson, Dennis E.

    2013-01-01

    Background. Fat accumulation in muscle may contribute to age-related declines in muscle function and is indicated by reduced attenuation of x-rays by muscle tissue in computed tomography scans. Reduced trunk muscle attenuation is associated with poor physical function, low back pain, and increased hyperkyphosis in older adults. However, variations in trunk muscle attenuation with age, sex and between specific muscles have not been investigated. Methods. A cross-sectional examination of trunk muscle attenuation in computed tomography scans was performed in 60 younger (35–50 years) and 60 older (75–87 years) adults randomly selected from participants in the Framingham Heart Study Offspring and Third Generation Multidetector Computed Tomography Study. Computed tomography attenuation of 11 trunk muscles was measured at vertebral levels T8 and L3, and the effects of age, sex, and specific muscle on computed tomography attenuation of trunk muscles were determined. Results. Muscle attenuation varied by specific muscle (p < .001), was lower in older adults (p < .001), and was generally lower in women than in men (p < .001), although not in all muscles. Age-related differences in muscle attenuation varied with specific muscle (p < .001), with the largest age differences occurring in the paraspinal and abdominal muscles. Conclusions. Trunk muscle attenuation is lower in older adults than in younger adults in both women and men, but such age-related differences vary widely between muscle groups. The reasons that some muscles exhibit larger age-related differences in fat content than others should be further explored to better understand age-related changes in functional capacity and postural stability. PMID:22904095

  13. Age-dependent morphological and compositional variations on Ceres

    NASA Astrophysics Data System (ADS)

    Jaumann, Ralf

    2016-04-01

    Extended smooth plains cover the interior of a number of craters on Ceres. Smooth plains appear on different topographic levels associated with pits and flow-like features that overrun crater rims. The material forming these plains also ponds in depressions and smaller craters and cover the pre-existing surface creating distinct geological boundaries. Ikapati crater shows smooth plains on different topographic levels associated with pits and flow-like features that overrun crater rims. The material forming these plains, ponds in depressions and smaller craters and cover the pre-existing surface creating a distinct geological boundary. The interior of Occator also exhibits extended plains of ponded material, multiple flows originating from the center overwhelming the mass wasting deposits from the rim, dome-like features, vents cracks and fissures. Furthermore, crater densities on Occator's floor are lower than those on the ejecta blanket indicating a post-impact formation age of the flows. The flows to the northeast appear to originate from the central region and move slightly uphill. This indicates either a feeding zone that pushes the flows forward by supplying low-viscosity material or a depression of the crater center, possibly after discharging a subsurface reservoir. The plains and flows as well as some areas surrounding the craters appear spectrally blue. Both plains and flow material are characterized in camera and spectrometer visible spectra by a slightly negative slope with a gradual drop off up to 10% in reflectance from 0.5μm to 1μm. Although the spectral variations in the visible are subtle, they are clearly expressed in the color ratio composite. The crater densities of 20 locations across the surface of Ceres with different spectral behavior were analyzed in order to investigate the age dependence of spectral surface features. The results indicate that bluish material is mainly associated with the youngest impact craters on Ceres (< 0.5 Ga) while

  14. Animal models of age related macular degeneration

    PubMed Central

    Pennesi, Mark E.; Neuringer, Martha; Courtney, Robert J.

    2013-01-01

    Age related macular degeneration (AMD) is the leading cause of vision loss of those over the age of 65 in the industrialized world. The prevalence and need to develop effective treatments for AMD has lead to the development of multiple animal models. AMD is a complex and heterogeneous disease that involves the interaction of both genetic and environmental factors with the unique anatomy of the human macula. Models in mice, rats, rabbits, pigs and non-human primates have recreated many of the histological features of AMD and provided much insight into the underlying pathological mechanisms of this disease. In spite of the large number of models developed, no one model yet recapitulates all of the features of human AMD. However, these models have helped reveal the roles of chronic oxidative damage, inflammation and immune dysregulation, and lipid metabolism in the development of AMD. Models for induced choroidal neovascularization have served as the backbone for testing new therapies. This article will review the diversity of animal models that exist for AMD as well as their strengths and limitations. PMID:22705444

  15. Distraction can reduce age-related forgetting.

    PubMed

    Biss, Renée K; Ngo, K W Joan; Hasher, Lynn; Campbell, Karen L; Rowe, Gillian

    2013-04-01

    In three experiments, we assessed whether older adults' generally greater tendency to process distracting information can be used to minimize widely reported age-related differences in forgetting. Younger and older adults studied and recalled a list of words on an initial test and again on a surprise test after a 15-min delay. In the middle (Experiments 1a and 2) or at the end (Experiment 3) of the delay, participants completed a 1-back task in which half of the studied words appeared as distractors. Across all experiments, older adults reliably forgot unrepeated words; however, older adults rarely or never forgot the words that had appeared as distractors, whereas younger adults forgot words in both categories. Exposure to distraction may serve as a rehearsal episode for older adults, and thus as a method by which general distractibility may be co-opted to boost memory. PMID:23426890

  16. Macular carotenoids and age-related maculopathy.

    PubMed

    O'Connell, Eamonn; Neelam, Kumari; Nolan, John; Au Eong, Kah-Guan; Beatty, Stephan

    2006-11-01

    Lutein (L) and zeaxanthin (Z) are concentrated at the macula, where they are collectively known as macular pigment (MP), and where they are believed to play a major role in protecting retinal tissues against oxidative stress. Whilst the exact pathogenesis of age-related maculopathy (ARM) remains unknown, the disruption of cellular processes by oxidative stress may play an important role. Manipulation of dietary intake of L and Z has been shown to augment MP, thereby raising hopes that dietary supplementation with these carotenoids might prevent, delay, or modify the course of ARM. This article discusses the scientific rationale supporting the hypothesis that L and Z are protective against ARM, and presents the recent evidence germane to this theory. PMID:17160199

  17. Medical bioremediation of age-related diseases

    PubMed Central

    Mathieu, Jacques M; Schloendorn, John; Rittmann, Bruce E; Alvarez, Pedro JJ

    2009-01-01

    Catabolic insufficiency in humans leads to the gradual accumulation of a number of pathogenic compounds associated with age-related diseases, including atherosclerosis, Alzheimer's disease, and macular degeneration. Removal of these compounds is a widely researched therapeutic option, but the use of antibodies and endogenous human enzymes has failed to produce effective treatments, and may pose risks to cellular homeostasis. Another alternative is "medical bioremediation," the use of microbial enzymes to augment missing catabolic functions. The microbial genetic diversity in most natural environments provides a resource that can be mined for enzymes capable of degrading just about any energy-rich organic compound. This review discusses targets for biodegradation, the identification of candidate microbial enzymes, and enzyme-delivery methods. PMID:19358742

  18. [Epidemiology of age-related macular degeneration].

    PubMed

    Brandl, C; Stark, K J; Wintergerst, M; Heinemann, M; Heid, I M; Finger, R P

    2016-09-01

    Age-related macular degeneration (AMD) is the main cause of blindness in industrialized societies. Population-based epidemiological investigations generate important data on prevalence, incidence, risk factors, and future trends. This review summarizes the most important epidemiological studies on AMD with a focus on their transferability to Germany including existing evidence for the main risk factors for AMD development and progression. Future tasks, such as the standardization of grading systems and the use of recent retinal imaging technology in epidemiological studies are discussed. In Germany, epidemiological data on AMD are scarce. However, the need for epidemiological research in ophthalmology is currently being addressed by several recently started population-based studies. PMID:27541733

  19. Age-related macular degeneration: current treatments

    PubMed Central

    Hubschman, Jean Pierre; Reddy, Shantan; Schwartz, Steven D

    2009-01-01

    Purpose: Although important progress has been made in understanding age-related macular degeneration (AMD), management of the disease continues to be a challenge. AMD research has led to a widening of available treatment options and improved prognostic perspectives. This essay reviews these treatment options. Design: Interpretative essay. Methods: Literature review and interpretation. Results: Current treatments to preserve vision in patients with non-exudative AMD include antioxidant vitamins and mineral supplementations. Exudative AMD is currently most often treated monthly with anti-VEGF intravitreal injections. However, investigators are beginning to experiment with combination therapy and surgical approaches in an attempt to limit the number of treatment and reduce the financial burden on the health care system. Conclusion: By better understanding the basis and pathogenesis of AMD, newer therapies will continue to be developed that target specific pathways in patients with AMD, with the hoped for outcome of better management of the disease and improved visual acuity. PMID:19668560

  20. Age-related consequences of childhood obesity.

    PubMed

    Kelsey, Megan M; Zaepfel, Alysia; Bjornstad, Petter; Nadeau, Kristen J

    2014-01-01

    The severity and frequency of childhood obesity has increased significantly over the past three to four decades. The health effects of increased body mass index as a child may significantly impact obese youth as they age. However, many of the long-term outcomes of childhood obesity have yet to be studied. This article examines the currently available longitudinal data evaluating the effects of childhood obesity on adult outcomes. Consequences of obesity include an increased risk of developing the metabolic syndrome, cardiovascular disease, type 2 diabetes and its associated retinal and renal complications, nonalcoholic fatty liver disease, obstructive sleep apnea, polycystic ovarian syndrome, infertility, asthma, orthopedic complications, psychiatric disease, and increased rates of cancer, among others. These disorders can start as early as childhood, and such early onset increases the likelihood of early morbidity and mortality. Being obese as a child also increases the likelihood of being obese as an adult, and obesity in adulthood also leads to obesity-related complications. This review outlines the evidence for childhood obesity as a predictor of adult obesity and obesity-related disorders, thereby emphasizing the importance of early intervention to prevent the onset of obesity in childhood. PMID:24434909

  1. Nut consumption and age-related disease.

    PubMed

    Grosso, G; Estruch, R

    2016-02-01

    Current knowledge on the effects of nut consumption on human health has rapidly increased in recent years and it now appears that nuts may play a role in the prevention of chronic age-related diseases. Frequent nut consumption has been associated with better metabolic status, decreased body weight as well as lower body weight gain over time and thus reduce the risk of obesity. The effect of nuts on glucose metabolism, blood lipids, and blood pressure is still controversial. However, significant decreased cardiovascular risk has been reported in a number of observational and clinical intervention studies. Thus, findings from cohort studies show that increased nut consumption is associated with a reduced risk of cardiovascular disease and mortality (especially that due to cardiovascular-related causes). Similarly, nut consumption has been also associated with reduced risk of certain cancers, such as colorectal, endometrial, and pancreatic neoplasms. Evidence regarding nut consumption and neurological or psychiatric disorders is scarce, but a number of studies suggest significant protective effects against depression, mild cognitive disorders and Alzheimer's disease. The underlying mechanisms appear to include antioxidant and anti-inflammatory actions, particularly related to their mono- and polyunsaturated fatty acids (MUFA and PUFA, as well as vitamin and polyphenol content). MUFA have been demonstrated to improve pancreatic beta-cell function and regulation of postprandial glycemia and insulin sensitivity. PUFA may act on the central nervous system protecting neuronal and cell-signaling function and maintenance. The fiber and mineral content of nuts may also confer health benefits. Nuts therefore show promise as useful adjuvants to prevent, delay or ameliorate a number of chronic conditions in older people. Their association with decreased mortality suggests a potential in reducing disease burden, including cardiovascular disease, cancer, and cognitive impairments

  2. Spatial and temporal variations in the age structure of Arctic sea ice

    USGS Publications Warehouse

    Belchansky, G.I.; Douglas, D.C.; Platonov, N.G.

    2005-01-01

    Spatial and temporal variations in the age structure of Arctic sea ice are investigated using a new reversechronology algorithm that tracks ice-covered pixels to their location and date of origin based on ice motion and concentration data. The Beaufort Gyre tends to harbor the oldest (>10 years old) sea ice in the western Arctic while direct ice advection pathways toward the Transpolar Drift Stream maintain relatively young (???5 years) ice in the eastern Arctic. Persistent net losses (-4.2% yr-1) in extent of ice >10 years old (10+ year age class) were observed during 1989-2003. Since the mid-1990s, losses to the 10+ year age class lacked compensation by recruitment due to a prior depletion of all mature (6-10 year) age classes. Survival of the 1994 and 1996-1998 sea ice generations reestablished most mature age classes, and thereby the potential to increase extent of the 10+ year age class during the mid-2000s. Copyright 2005 by the American Geophysical Union.

  3. 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…

  4. 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.…

  5. Association of Age Related Macular Degeneration and Age Related Hearing Impairment

    PubMed Central

    Ghasemi, Hassan; Pourakbari, Malihe Shahidi; Entezari, Morteza; Yarmohammadi, Mohammad Ebrahim

    2016-01-01

    Purpose: To evaluate the association between age-related macular degeneration (ARMD) and sensory neural hearing impairment (SHI). Methods: In this case-control study, hearing status of 46 consecutive patients with ARMD were compared with 46 age-matched cases without clinical ARMD as a control group. In all patients, retinal involvements were confirmed by clinical examination, fluorescein angiography (FA) and optical coherence tomography (OCT). All participants were examined with an otoscope and underwent audiological tests including pure tone audiometry (PTA), speech reception threshold (SRT), speech discrimination score (SDS), tympanometry, reflex tests and auditory brainstem response (ABR). Results: A significant (P = 0.009) association was present between ARMD, especially with exudative and choroidal neovascularization (CNV) components, and age-related hearing impairment primarily involving high frequencies. Patients had higher SRT and lower SDS against anticipated presbycusis than control subjects. Similar results were detected in exudative, CNV and scar patterns supporting an association between late ARMD with SRT and SDS abnormalities. ABR showed significantly prolonged wave I and IV latency times in ARMD (P = 0.034 and 0.022, respectively). Average latency periods for wave I in geographic atrophy (GA) and CNV, and that for wave IV in drusen patterns of ARMD were significantly higher than controls (P = 0.030, 0.007 and 0.050, respectively). Conclusion: The association between ARMD and age-related SHI may be attributed to common anatomical components such as melanin in these two sensory organs. PMID:27195086

  6. Age-related hypoxia in CNS pathology.

    PubMed

    Bădescu, George Mihai; Fîlfan, Mădălina; Ciobanu, Ovidiu; Dumbravă, DănuŢ Adrian; Popa-Wagner, Aurel

    2016-01-01

    Although neuropathological conditions differ in the etiology of the inflammatory response, cellular and molecular mechanisms of neuroinflammation are probably similar in aging, hypertension, depression and cognitive impairment. Moreover, a number of common risk factors such as obesity, hypertension, diabetes and atherosclerosis are increasingly understood to act as "silent contributors" to neuroinflammation and can underlie the development of disorders such as cerebral small vessel disease (cSVD) and subsequent dementia. On the other hand, acute neuroinflammation, such as in response to traumatic or cerebral ischemia, aggravates the acute damage and can lead to a number of pathological such as depression, post-stroke dementia and potentially neurodegeneration. All of those sequelae impair recovery and most of them provide the ground for further cerebrovascular events and a vicious cycle develops. Therefore, understanding the mechanisms associated with vascular dementia, stroke and related complications is of paramount importance in improving current preventive and therapeutic interventions. Likewise, understanding of molecular factors and pathways associated with neuroinflammation will eventually enable the discovery and implementation of new diagnostic and therapeutic strategies indicated in a wide range of neurological conditions. PMID:27151686

  7. Molecular mechanisms of ageing and related diseases.

    PubMed

    Liu, Jun-Ping

    2014-07-01

    Human and other multicellular life species age, and ageing processes become dominant during the late phase of life. Recent studies challenge this dogma, suggesting that ageing does not occur in some animal species. In mammals, cell replicative senescence occurs as early as before birth (i.e. in embryos) under physiological conditions. How the molecular machinery operates and why ageing cells dominate under some circumstances are intriguing questions. Recent studies show that cell ageing involves extensive cellular remodelling, including telomere attrition, heterochromatin formation, endoplasmic reticulum stress, mitochondrial disorders and lysosome processing organelles and chromatins. This article provides an update on the molecular mechanisms underlying the ageing of various cell types, the newly described developmental and programmed replicative senescence and the critical roles of cellular organelles and effectors in Parkinson's disease, diabetes, hypertension and dyskeratosis congenita. PMID:24798238

  8. Tract-specific and age-related variations of the spinal cord microstructure: a multi-parametric MRI study using diffusion tensor imaging (DTI) and inhomogeneous magnetization transfer (ihMT).

    PubMed

    Taso, Manuel; Girard, Olivier M; Duhamel, Guillaume; Le Troter, Arnaud; Feiweier, Thorsten; Guye, Maxime; Ranjeva, Jean-Philippe; Callot, Virginie

    2016-06-01

    Being able to finely characterize the spinal cord (SC) microstructure and its alterations is a key point when investigating neural damage mechanisms encountered in different central nervous system (CNS) pathologies, such as multiple sclerosis, amyotrophic lateral sclerosis or myelopathy. Based on novel methods, including inhomogeneous magnetization transfer (ihMT) and dedicated SC probabilistic atlas post-processing, the present study focuses on the in vivo characterization of the healthy SC tissue in terms of regional microstructure differences between (i) upper and lower cervical vertebral levels and (ii) sensory and motor tracts, as well as differences attributed to normal aging. Forty-eight healthy volunteers aged from 20 to 70 years old were included in the study and scanned at 3 T using axial high-resolution T2 *-w imaging, diffusion tensor imaging (DTI) and ihMT, at two vertebral levels (C2 and C5). A processing pipeline with minimal user intervention, SC segmentation and spatial normalization into a reference space was implemented in order to assess quantitative morphological and structural parameters (cross-sectional areas, scalar DTI and MT/ihMT metrics) in specific white and gray matter regions of interest. The multi-parametric MRI metrics collected allowed upper and lower cervical levels to be distinguished, with higher ihMT ratio (ihMTR), higher axial diffusivity (λ∥ ) and lower radial diffusivity (λ⊥ ) at C2 compared with C5. Significant differences were also observed between white matter fascicles, with higher ihMTR and lower λ∥ in motor tracts compared with posterior sensory tracts. Finally, aging was found to be associated with significant metric alterations (decreased ihMTR and λ∥ ). The methodology proposed here, which can be easily transferred to the clinic, provides new insights for SC characterization. It bears great potential to study focal and diffuse SC damage in neurodegenerative and demyelinating diseases. Copyright

  9. 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…

  10. Growth factors, aging and age-related diseases.

    PubMed

    Balasubramanian, Priya; Longo, Valter D

    2016-06-01

    Simple organisms including yeast and flies with mutations in the IGF-1 and Tor-S6K pathways are dwarfs, are highly protected from toxins, and survive up to 3 times longer. Similarly, dwarf mice with deficiencies in the growth hormone-IGF-I axis are also long lived and protected from diseases. We recently reported that humans with Growth Hormone Receptor Deficiency (GHRD) rarely develop cancer or diabetes. These findings are in agreement with the effect of defects in the Tor-S6K pathways in causing dwarfism and protection of DNA. Because protein restriction reduces both GHR-IGF-1 axis and Tor-S6K activity, we examined links between protein intake, disease, and mortality in over 6000 US subjects in the NHANES CDC database. Respondents aged 50-65 reporting a high protein intake displayed an increase in IGF-I levels, a 75% increased risk of overall mortality and a 3-4 fold increased risk of cancer mortality in agreement with findings in mouse experiments. These studies point to a conserved link between proteins and amino acids, GHR-IGF-1/insulin, Tor-S6k signaling, aging, and diseases. PMID:26883276

  11. Aging Is Not a Disease: Distinguishing Age-Related Macular Degeneration from Aging

    PubMed Central

    Ardeljan, Daniel; Chan, Chi-Chao

    2013-01-01

    Age-related macular degeneration (AMD) is a disease of the outer retina, characterized most significantly by atrophy of photoreceptors and retinal pigment epithelium accompanied with or without choroidal neovascularization. Development of AMD has been recognized as contingent on environmental and genetic risk factors, the strongest being advanced age. In this review, we highlight pathogenic changes that destabilize ocular homeostasis and promote AMD development. With normal aging, photoreceptors are steadily lost, Bruch's membrane thickens, the choroid thins, and hard drusen may form in the periphery. In AMD, many of these changes are exacerbated in addition to the development of disease-specific factors such as soft macular drusen. Para-inflammation, which can be thought of as an intermediate between basal and robust levels of inflammation, develops within the retina in an attempt to maintain ocular homeostasis, reflected by increased expression of the anti-inflammatory cytokine IL-10 coupled with shifts in macrophage plasticity from the pro-inflammatory M1 to the anti-inflammatory M2 polarization. In AMD, imbalances in the M1 and M2 populations together with activation of retinal microglia are observed and potentially contribute to tissue degeneration. Nonetheless, the retina persists in a state of chronic inflammation and increased expression of certain cytokines and inflammasomes is observed. Since not everyone develops AMD, the vital question to ask is how the body establishes a balance between normal age-related changes and the pathological phenotypes in AMD. PMID:23933169

  12. Relative Age Effect in Masters Sports: Replication and Extension

    ERIC Educational Resources Information Center

    Medic, Nikola; Starkes, Janet L.; Weir, Patricia L.; Young, Bradley W.; Grove, J. Robert

    2009-01-01

    The relative age effect refers to the performance-related advantage of being born early in a cohort or selection year. Until recently it was unknown whether the relative age effect generalizes across the lifespan. Medic, Starkes, and Young (2007) reasoned that the 5-year age categories that are widely used in masters-level sports to organize…

  13. Anatomic variations of the root canal of the rat according to age.

    PubMed

    Gómez, Paula A; Cabrini, Rómulo L

    2004-01-01

    The mesial canal of the first lower molar of the rat has been used as an experimental model in Endodontics. The present study involves a detailed analysis of its structural variations as a function of age and thus contributes to its characterization and adequate use as an experimental model. We evaluated 60 molars of Wistar rats of different body weight: (group 1: 300-399 g, n=22; group 2: 400-499 g, n=16; group 3: 600-700 g, n=22). The samples were radiographed employing a standardized system. Total canal length and volume were measured on enlarged projections of the radiographs. Canal diameter was measured at coronary, middle and apical levels and employed to estimate the area of canal cross-section as an indicator of potential flow or metabolic interchange. From the second age group onwards, we detected radicular hypercementosis that increased canal length and resulted in the formation of a complex apical delta. The canal diameter decreased very significantly in the apical third. The estimated flow expressed in terms of the area of cross-section on the projection decreased from 1.2 mm2 in Group 1 to 0.05 mm2 in Group 2. Group 3 did not differ significantly from Group 2. The present results reveal that the spontaneous, age-related variations in canal anatomy described herein must be considered when performing experimental endodontics in rats. PMID:15584260

  14. Age-related elemental change in bones

    NASA Astrophysics Data System (ADS)

    Wang, C.; Eisa, M. H.; Jin, W.; Shen, H.; Mi, Y.; Gao, J.; Zhou, Y.; Yao, H.; Zhao, Y.

    2008-04-01

    To investigate age dependence of the bone element contents and structure, lumbar and femur from Sprague-Dawley (SD) rats were chosen for their more susceptibility to fracture. These rats were divided into to 5 age groups: 1, 4, 7, 11 and 25 month-age, corresponding human beings from the young to the old. The elements contents were detected by external Proton Induced X-ray emission (PIXE) technique. X-ray Absorption Fine Structure (XAFS) method was also applied to obtain information about calcium (Ca) and phosphor (P) structure. It was found that Ca content, Ca/P ratio, valance state of Ca and P and their coordinate structure remains unaltered with age variance, whereas the content of strontium (Sr) was significantly decreasing. Sr concentration may provide a new parameter for diagnosis of bone disorder.

  15. Age Related Changes in Autonomic Functions

    PubMed Central

    Amir, Mohammed; Pakhare, Abhijit; Rathi, Preeti; Chaudhary, Lalita

    2016-01-01

    Introduction Autonomic Nervous System (ANS) imbalance may trigger or enhance pathology in different organ systems that varies in different age groups hence objective of present study was to evaluate association of different Age-groups with autonomic functions. Materials and Methods A cross-sectional study was conducted in 62 healthy volunteers in Department of Physiology LLRM Medical College Meerut, India. Volunteers were divided into three groups as younger (15-45 years), middle (45-60) and elder age (above 60), Autonomic functions were tested in three domains viz. Cardio-vagal, adrenergic and sudomotor functions. Numerical data was summarized as mean and standard deviation and categorical data as count and percentage. ANOVA and Chi-square test were used to find difference among groups, p<0.05 was considered statistically significant. Results Mean ± standard deviation OHT(Orthostatic Hypotension Test) among of younger, middle and elder age groups were 8.80±2.28, 13.40±4.64 and 21.82±6.04 respectively which represent decrease in sympathetic functions with age (p<0.001). Cardio-vagal or parasympathetic responses indicated by DBT (Deep Breathing Test) Valsalva and 30:15 ratio of HR response to standing tests has shown statistically significant (p<0.001) decrease in mean response with increasing age. Sudomotor response appeared normal in younger and middle group but was interrupted in more than half of elderly people (p<0.001). Conclusion Sympathetic responses & para-sympathetic responses have shown the significant decline with increasing age group. Sudomotor responses were partially interrupted in elderly age group. PMID:27134865

  16. Variation of ocean sediment thickness with crustal age

    NASA Astrophysics Data System (ADS)

    Olson, Peter; Reynolds, Evan; Hinnov, Linda; Goswami, Arghya

    2016-04-01

    Global ocean sediment thickness and present-day ocean sediment accumulation rates are analyzed with respect to the age of the underlying ocean crust. Trends in average sediment thickness and present-day accumulation rate are well fit by cubic polynomials in crustal age for the global ocean and for individual ocean basins. Sediment thickness and accumulation rates are larger in the North and South Atlantic and Indian Oceans compared to the Pacific Ocean, primarily because the anomalous sediment accumulations that followed continental rifting and collision in the Atlantic and Indian Ocean basins are missing in the Pacific Ocean. Modern ocean sediment accumulation rates, extrapolated into the past assuming steady state conditions, account within uncertainties for the global average sediment thickness on 0-65 Ma (Cenozoic age) ocean crust, while the profile of anomalously thick sediments on older (Mesozoic age) ocean crust is well fit by adding localized, diffusive sediment transport from a steady state source referenced to the adjacent continental margin. Apart from a distinct 0-5 Ma (Quaternary age) sediment pulse, deviations in average sediment thickness from this simple model are generally small and are uncorrelated across ocean basins.

  17. Bodacious Berry, Potency Wood and the Aging Monster: Gender and Age Relations in Anti-Aging Ads

    ERIC Educational Resources Information Center

    Calasanti, Toni

    2007-01-01

    This paper situates age discrimination within a broader system of age relations that intersects with other inequalities, and then uses that framework to analyze internet advertisements for the anti-aging industry. Such ads reinforce age and gender relations by positing old people as worthwhile only to the extent that they look and act like those…

  18. Molecular pathology of age-related macular degeneration

    PubMed Central

    Ding, Xiaoyan; Patel, Mrinali; Chan, Chi-Chao

    2009-01-01

    Age-related macular degeneration (AMD) is a leading cause of irreversible blindness in the world. Although the etiology and pathogenesis of AMD remain largely unclear, a complex interaction of genetic and environmental factors is thought to exist. AMD pathology is characterized by degeneration involving the retinal photoreceptors, retinal pigment epithelium, and Bruch’s membrane, as well as, in some cases, alterations in choroidal capillaries. Recent research on the genetic and molecular underpinnings of AMD brings to light several basic molecular pathways and pathophysiological processes that might mediate AMD risk, progression, and/or response to therapy. This review summarizes, in detail, the molecular pathological findings in both humans and animal models, including genetic variations in CFH, CX3CR1, and ARMS2/HtrA1, as well as the role of numerous molecules implicated in inflammation, apoptosis, cholesterol trafficking, angiogenesis, and oxidative stress. PMID:19026761

  19. 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

  20. Statins for age-related macular degeneration

    PubMed Central

    Gehlbach, Peter; Li, Tianjing; Hatef, Elham

    2016-01-01

    Background Age-related macular degeneration (AMD) is a progressive late onset disorder of the macula affecting central vision. Age-related macular degeneration is the leading cause of blindness in people over 65 years in industrialized countries. Recent epidemiologic, genetic, and pathological evidence has shown AMD shares a number of risk factors with atherosclerosis, leading to the hypothesis that statins may exert protective effects in AMD. Objectives The objective of this review was to examine the effectiveness of statins compared with other treatments, no treatment, or placebo in delaying the onset and progression of AMD. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2014, Issue 6), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to June 2014), EMBASE (January 1980 to June 2014), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to June 2014), PubMed (January 1946 to June 2014), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov), and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 5 June 2014. Selection criteria We included randomized controlled trials (RCTs) that compared statins with other treatments, no treatment, or placebo in participants who were either susceptible to or diagnosed as having early stages of AMD. Data collection and analysis We used standard methodological procedures expected by The Cochrane Collaboration. Two authors independently evaluated the search results against the selection criteria, abstracted data, and assessed risk of bias. We did not perform meta-analysis due to heterogeneity in the interventions and outcomes among the

  1. 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%.

  2. AGE-RELATED SUSCEPTIBILITY: A GENOMICS APPROACH.

    EPA Science Inventory

    By the year 2030 more than 70 million Americans will be over the age of 65. These older adults are a subpopulation that may have special susceptibility to toxic insult due to critical characteristics of their life-stage. Current EPA testing guidelines do not identify the elderl...

  3. Age-Related Changes in Visual Pseudoneglect

    ERIC Educational Resources Information Center

    Schmitz, Remy; Peigneux, Philippe

    2011-01-01

    Pseudoneglect is a slight but consistent leftward attentional bias commonly observed in healthy young populations, purportedly explained by right hemispheric dominance. It has been suggested that normal aging might be associated with a decline of the right hemisphere. According to this hypothesis, a few studies have shown that elderly tend to…

  4. Variations on Fibrinogen-Erythrocyte Interactions during Cell Aging

    PubMed Central

    Carvalho, Filomena A.; de Oliveira, Sofia; Freitas, Teresa; Gonçalves, Sónia; Santos, Nuno C.

    2011-01-01

    Erythrocyte hyperaggregation, a cardiovascular risk factor, is considered to be caused by an increase in plasma adhesion proteins, particularly fibrinogen. We have recently reported a specific binding between fibrinogen and an erythrocyte integrin receptor with a β3 or β3-like subunit. In this study we evaluate the influence of erythrocyte aging on the fibrinogen binding. By atomic force microscopy-based force spectroscopy measurements we found that increasing erythrocyte age, there is a decrease of the binding to fibrinogen by decreasing the frequency of its occurrence but not its force. This observation is reinforced by zeta-potential and fluorescence spectroscopy measurements. We conclude that upon erythrocyte aging the number of fibrinogen molecules bound to each cell decreases significantly, due to the progressive impairment of the specific fibrinogen-erythrocyte receptor interaction. Knowing that younger erythrocytes bind more to fibrinogen, we could presume that this population is the main contributor to the cardiovascular diseases associated with increased fibrinogen content in blood, which could disturb the blood flow. Our data also show that the sialic acids exposed on the erythrocyte membrane contribute for the interaction with fibrinogen, possibly by facilitating its binding to the erythrocyte membrane receptor. PMID:21464904

  5. 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. PMID:27119585

  6. Age-related forgetting in locomotor adaptation

    PubMed Central

    Malone, Laura A.; Bastian, Amy J.

    2016-01-01

    The healthy aging process affects the ability to learn and remember new facts and tasks. Prior work has shown that motor learning can be adversely affected by non-motor deficits, such as time. Here we investigated how age, and a dual task influence the learning and forgetting of a new walking pattern. We studied healthy younger (<30 yo) and older adults (>50 yo) as they alternated between 5-minute bouts of split-belt treadmill walking and resting. Older subjects learned a new walking pattern at the same rate as younger subjects, but forgot some of the new pattern during the rest breaks. We tested if forgetting was due to reliance on a cognitive strategy that was not fully engaged after rest breaks. When older subjects performed a dual cognitive task to reduce strategic control of split-belt walking, their adaptation rate slowed, but they still forgot much of the new pattern during the rest breaks. Our results demonstrate that the healthy aging process weakens motor memories during rest breaks and that this phenomenon cannot be explained solely by reliance on a conscious strategy in older adults. PMID:26589520

  7. International variation in reported livebirth prevalence rates of Down syndrome, adjusted for maternal age.

    PubMed

    Carothers, A D; Hecht, C A; Hook, E B

    1999-05-01

    Reported livebirth prevalence of Down syndrome (DS) may be affected by the maternal age distribution of the population, completeness of ascertainment, accuracy of diagnosis, extent of selective prenatal termination of affected pregnancies, and as yet unidentified genetic and environmental factors. To search for evidence of the latter, we reviewed all published reports in which it was possible to adjust both for effects of maternal age and for selective termination (where relevant). We constructed indices that allowed direct comparisons of prevalence rates after standardising for maternal age. Reference rates were derived from studies previously identified as having near complete ascertainment. An index value significantly different from 1 may result from random fluctuations, as well as from variations in the factors listed above. We found 49 population groups for which an index could be calculated. Methodological descriptions suggested that low values could often be attributed to under-ascertainment. A possible exception concerned African-American groups, though even among these most acceptable studies were compatible with an index value of 1. As we have reported elsewhere, there was also a suggestive increase in rates among US residents of Mexican or Central American origin. Nevertheless, our results suggest that "real" variation between population groups reported to date probably amounts to no more than +/-25%. However, reliable data in many human populations are lacking including, surprisingly, some jurisdictions with relatively advanced health care systems. We suggest that future reports of DS livebirth prevalence should routinely present data that allow calculation of an index standardised for maternal age and adjusted for elective prenatal terminations. PMID:10353785

  8. Mitochondrial DNA variation in the Viking age population of Norway

    PubMed Central

    Krzewińska, Maja; Bjørnstad, Gro; Skoglund, Pontus; Olason, Pall Isolfur; Bill, Jan; Götherström, Anders; Hagelberg, Erika

    2015-01-01

    The medieval Norsemen or Vikings had an important biological and cultural impact on many parts of Europe through raids, colonization and trade, from about AD 793 to 1066. To help understand the genetic affinities of the ancient Norsemen, and their genetic contribution to the gene pool of other Europeans, we analysed DNA markers in Late Iron Age skeletal remains from Norway. DNA was extracted from 80 individuals, and mitochondrial DNA polymorphisms were detected by next-generation sequencing. The sequences of 45 ancient Norwegians were verified as genuine through the identification of damage patterns characteristic of ancient DNA. The ancient Norwegians were genetically similar to previously analysed ancient Icelanders, and to present-day Shetland and Orkney Islanders, Norwegians, Swedes, Scots, English, German and French. The Viking Age population had higher frequencies of K*, U*, V* and I* haplogroups than their modern counterparts, but a lower proportion of T* and H* haplogroups. Three individuals carried haplotypes that are rare in Norway today (U5b1b1, Hg A* and an uncommon variant of H*). Our combined analyses indicate that Norse women were important agents in the overseas expansion and settlement of the Vikings, and that women from the Orkneys and Western Isles contributed to the colonization of Iceland. PMID:25487335

  9. Mitochondrial DNA variation in the Viking age population of Norway.

    PubMed

    Krzewińska, Maja; Bjørnstad, Gro; Skoglund, Pontus; Olason, Pall Isolfur; Bill, Jan; Götherström, Anders; Hagelberg, Erika

    2015-01-19

    The medieval Norsemen or Vikings had an important biological and cultural impact on many parts of Europe through raids, colonization and trade, from about AD 793 to 1066. To help understand the genetic affinities of the ancient Norsemen, and their genetic contribution to the gene pool of other Europeans, we analysed DNA markers in Late Iron Age skeletal remains from Norway. DNA was extracted from 80 individuals, and mitochondrial DNA polymorphisms were detected by next-generation sequencing. The sequences of 45 ancient Norwegians were verified as genuine through the identification of damage patterns characteristic of ancient DNA. The ancient Norwegians were genetically similar to previously analysed ancient Icelanders, and to present-day Shetland and Orkney Islanders, Norwegians, Swedes, Scots, English, German and French. The Viking Age population had higher frequencies of K*, U*, V* and I* haplogroups than their modern counterparts, but a lower proportion of T* and H* haplogroups. Three individuals carried haplotypes that are rare in Norway today (U5b1b1, Hg A* and an uncommon variant of H*). Our combined analyses indicate that Norse women were important agents in the overseas expansion and settlement of the Vikings, and that women from the Orkneys and Western Isles contributed to the colonization of Iceland. PMID:25487335

  10. Low Calorie Diet Affects Aging-Related Factors

    MedlinePlus

    ... Research News From NIH Low Calorie Diet Affects Aging-Related Factors Past Issues / Summer 2006 Table of ... project sponsored by the NIH's National Institute on Aging (NIA) to learn more about the effects of ...

  11. Low Calorie Diet Affects Aging-Related Factors

    MedlinePlus

    ... Issue Past Issues Research News From NIH Low Calorie Diet Affects Aging-Related Factors Past Issues / Summer ... learn more about the effects of sustained low-calorie diets in humans on factors affecting aging. This ...

  12. Variations in Community Prevalence and Determinants of Recreational and Utilitarian Walking in Older Age

    PubMed Central

    Procter-Gray, Elizabeth; Leveille, Suzanne G.; Hannan, Marian T.; Cheng, Jie; Kane, Kevin; Li, Wenjun

    2015-01-01

    Background. Regular walking is critical to maintaining health in older age. We examined influences of individual and community factors on walking habits in older adults. Methods. We analyzed walking habits among participants of a prospective cohort study of 745 community-dwelling men and women, mainly aged 70 years or older. We estimated community variations in utilitarian and recreational walking, and examined whether the variations were attributable to community differences in individual and environmental factors. Results. Prevalence of recreational walking was relatively uniform while prevalence of utilitarian walking varied across the 16 communities in the study area. Both types of walking were associated with individual health and physical abilities. However, utilitarian walking was also strongly associated with several measures of neighborhood socioeconomic status and access to amenities while recreational walking was not. Conclusions. Utilitarian walking is strongly influenced by neighborhood environment, but intrinsic factors may be more important for recreational walking. Communities with the highest overall walking prevalence were those with the most utilitarian walkers. Public health promotion of regular walking should take this into account. PMID:26339507

  13. THE RELATIONSHIP BETWEEN CIRCADIAN BLOOD PRESSURE VARIATION AND AGE ANALYSED FROM 7-DAY MONITORING

    PubMed Central

    SIEGELOVÁ, J.; DUŠEK, J.; FIŠER, B.; HOMOLKA, P.; VANK, P.; MAŠEK, M.; HAVELKOVÁ, A.; CORNÉLISSEN, G.; HALBERG, F.

    2009-01-01

    The relationship between age and circadian blood pressure (BP) variation was the aim of the present study. One hundred and eighty-seven subjects (130 males, 57 females), 20-77 years old, were recruited for seven-day BP monitoring. Colin medical instruments (Komaki, Japan) were used for ambulatory BP monitoring (oscillation method, 30-minute interval between measurements). A sinusoidal curve was fitted (minimum square method) and the mean value and amplitude of the curve (double amplitude corresponds to the night-day difference) were evaluated on every day of monitoring. The average 7-day values of the mean (M) and of double amplitude (2A) for systolic BP (SBP), diastolic BP (DBP), and heart rate (HR) were determined in each subject. The mean values of M (±SD) for the whole group were: SBP- 127±8, DBP - 79±6 mmHg, HR - 70±6 bpm; of 2A: SBP - 21±7, DBP - 15±5 mmHg, HR - 15±6 bpm. A linear relationship between M of SBP and age (r=0.341, p< 0.001) and DBP and age (r=0.384, p<0.001) was found (difference between 20 and 77 years: SBP - 16, DBP - 12 mmHg). 2A of SBP and DBP was increasing with age up to 35 years, then the curve remained relatively flat up to 55 years (maximum at 45 years), and then it decreased again (difference between 45 and 77 years: SBP - 13mmHg, DBP - 12 mmHg). Heart rate M and 2A were age-independent. The mean values of SBP and DBP were increasing with age up to 75 years, but the night-day difference of SBP and DBP reached its maximum value at 45 years and then decreased. PMID:19436777

  14. Density variations of plastic carriers in metallic glasses during aging

    NASA Astrophysics Data System (ADS)

    Fan, Yue; Iwashita, Takuya; Egami, Takeshi

    Thermally induced deformation in metallic glasses was investigated by sampling the potential energy landscape (PEL) and probing the changes in the atomic properties (e.g. energy, displacement, stress). We demonstrate that there exists a universal plastic carrier in amorphous materials, which corresponds to the hopping between local minima on PEL. However very interestingly, the density of plastic carrier is largely affected by the aging history of the glasses. The higher fictive temperature (i . e . fast cooling rate), the larger density of plastic carrier is contained in the system. In particular, we observe a scaling of ρ~exp(- α/Tfic) , which is consistent with the prediction of shear transformation zone theory. The work is supported by U.S. Department of Energy.

  15. Age variations in judgments of 'great' art works.

    PubMed

    North, Adrian C; Hargreaves, David J

    2002-08-01

    This paper reports the results of two large-scale surveys concerning nominations of 'greatness' in the arts. In Study 1, 1088 respondents to a national newspaper survey nominated the greatest art works of the past 1000 years. Analyses indicated that there was some, albeit limited, evidence that older respondents nominated older art works, but no evidence of a tendency to nominate works produced during the participants' adolescence/early adulthood. In Study 2, a very brief questionnaire distributed through a CD retail chain, a national newspaper, and a national TV station asked 12,502 participants to nominate up to three of the greatest pop musicians of all time. Analyses indicated a tendency to nominate musicians who were successful while the participants themselves were in adolescence/early adulthood. These results are discussed in terms of the extent to which age can explain judgments of artistic 'greatness' within different art forms. PMID:12230837

  16. The precession constant of the Earth: Variations through the ice-age

    SciTech Connect

    Peltier, W.R.; Jiang, X.

    1994-10-01

    We directly calculate the history of variations in Earth`s precession constant H that are forced by variations in surface mass associated with late Pleistocene ice-age glaciation and deglaciation events. Our analyses show that the magnitude of Delta H/H(sub zero) is lower than that required to cause the recently hypothesized resonant reduction of the precession period.

  17. 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

  18. Variation in habitat suitability does not always relate to variation in species' plant functional traits

    PubMed Central

    Thuiller, Wilfried; Albert, Cécile H.; Dubuis, Anne; Randin, Christophe; Guisan, Antoine

    2010-01-01

    Habitat suitability models, which relate species occurrences to environmental variables, are assumed to predict suitable conditions for a given species. If these models are reliable, they should relate to change in plant growth and function. In this paper, we ask the question whether habitat suitability models are able to predict variation in plant functional traits, often assumed to be a good surrogate for a species' overall health and vigour. Using a thorough sampling design, we show a tight link between variation in plant functional traits and habitat suitability for some species, but not for others. Our contrasting results pave the way towards a better understanding of how species cope with varying habitat conditions and demonstrate that habitat suitability models can provide meaningful descriptions of the functional niche in some cases, but not in others. PMID:19793738

  19. Review: Axon pathology in age-related neurodegenerative disorders.

    PubMed

    Adalbert, R; Coleman, M P

    2013-02-01

    'Dying back' axon degeneration is a prominent feature of many age-related neurodegenerative disorders and is widespread in normal ageing. Although the mechanisms of disease- and age-related losses may differ, both contribute to symptoms. Here, we review recent advances in understanding axon pathology in age-related neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis and glaucoma. In particular, we highlight the importance of axonal transport, autophagy, traumatic brain injury and mitochondrial quality control. We then place these disease mechanisms in the context of changes to axons and dendrites that occur during normal ageing. We discuss what makes ageing such an important risk factor for many neurodegenerative disorders and conclude that the processes of normal ageing and disease combine at the molecular, cellular or systems levels in a range of disorders to produce symptoms. Pathology identical to disease also occurs at the cellular level in most elderly individuals. Thus, normal ageing and age-related disease are inextricably linked and the term 'healthy ageing' downplays the important contributions of cellular pathology. For a full understanding of normal ageing or age-related disease we must study both processes. PMID:23046254

  20. Age-related regulation of genes: slow homeostatic changes and age-dimension technology

    NASA Astrophysics Data System (ADS)

    Kurachi, Kotoku; Zhang, Kezhong; Huo, Jeffrey; Ameri, Afshin; Kuwahara, Mitsuhiro; Fontaine, Jean-Marc; Yamamoto, Kei; Kurachi, Sumiko

    2002-11-01

    Through systematic studies of pro- and anti-blood coagulation factors, we have determined molecular mechanisms involving two genetic elements, age-related stability element (ASE), GAGGAAG and age-related increase element (AIE), a unique stretch of dinucleotide repeats (AIE). ASE and AIE are essential for age-related patterns of stable and increased gene expression patterns, respectively. Such age-related gene regulatory mechanisms are also critical for explaining homeostasis in various physiological reactions as well as slow homeostatic changes in them. The age-related increase expression of the human factor IX (hFIX) gene requires the presence of both ASE and AIE, which apparently function additively. The anti-coagulant factor protein C (hPC) gene uses an ASE (CAGGAG) to produce age-related stable expression. Both ASE sequences (G/CAGAAG) share consensus sequence of the transcriptional factor PEA-3 element. No other similar sequences, including another PEA-3 consensus sequence, GAGGATG, function in conferring age-related gene regulation. The age-regulatory mechanisms involving ASE and AIE apparently function universally with different genes and across different animal species. These findings have led us to develop a new field of research and applications, which we named “age-dimension technology (ADT)”. ADT has exciting potential for modifying age-related expression of genes as well as associated physiological processes, and developing novel, more effective prophylaxis or treatments for age-related diseases.

  1. Climatic variation and age-specific survival in Asian elephants from Myanmar.

    PubMed

    Mumby, Hannah S; Courtiol, Alexandre; Mar, Khyne U; Lummaa, Virpi

    2013-05-01

    Concern about climate change has intensified interest in understanding how climatic variability affects animal life histories. Despite such effects being potentially most dramatic in large, long-lived, and slowly reproducing terrestrial mammals, little is known of the effects of climatic variation on survival in those species. Asian elephants (Elephas maximus) are endangered across their distribution, and inhabit regions characterized by high seasonality of temperature and rainfall. We investigated the effects of monthly climatic variation on survival and causes of death in Asian elephants using a unique demographic data set of 1024 semi-captive, longitudinally monitored elephants from four sites in Myanmar between 1965 and 2000. Temperature had a significant effect on survival in both sexes and across all ages. For elephants between 1 month and 17 years of age, maximal survival was reached at -24 degrees C, and any departures from this temperature increased mortality, whereas neonates and mature elephants had maximal survival at even lower temperatures. Although males experienced higher mortality overall, sex differences in these optimal temperatures were small. Because the elephants spent more time during a year in temperatures above 24 degrees C than in temperatures below it, most deaths occurred at hot (temperatures>24 degrees C) rather than cold periods. Decreased survival at higher temperatures resulted partially from increased deaths from infectious disease and heat stroke, whereas the lower survival in the coldest months was associated with an increase in noninfectious diseases and poor health in general. Survival was also related to rainfall, with the highest survival rates during the wettest months for all ages and sexes. Our results show that even the normal-range monsoon variation in climate can exert a large impact on elephant survival in Myanmar, leading to extensive absolute differences in mortality; switching from favorable to unfavorable climatic

  2. Age Related Decline in Postural Control Mechanisms.

    ERIC Educational Resources Information Center

    Stelmach, George E.; And Others

    1989-01-01

    Studied voluntary and reflexive mechanisms of postural control of young (N=8) and elderly (N=8) adults through measurement of reflexive reactions to large-fast and small-slow ankle rotation postural disturbances. Found reflexive mechanisms relatively intact for both groups although elderly appeared more disadvantaged when posture was under the…

  3. Age-Related Differences in Incidental Learning.

    ERIC Educational Resources Information Center

    Barrett, Terry R.

    Research has suggested that memory performance may be related to the extent of stimulus processing during acquisition. To examine processing efficiency and processing deficiency differences between younger and older adults, four studies were conducted. In the first study, young and old adults rated word lists, manipulated for generation specific…

  4. Evaluation of between- and within-breed variation in measures of weight-age relationships.

    PubMed

    Jenkins, T G; Kaps, M; Cundiff, L V; Ferrell, C L

    1991-08-01

    Variation between- and within-breeds was evaluated for accretion of weight from birth to 7 yr of age and hip height at 7 yr for 1,577 cows sired by Angus, Brahman, Brown Swiss, Charolais, Chianina, Gelbvieh, Hereford, Jersey, Limousin, Maine Anjou, Pinzgauer, Sahiwal, Simmental, South Devon, and Tarentaise and from either Angus or Hereford dams. Parameters from Wt = A (1 - Be-kt) were estimated by nonlinear regressions and provided estimates of mature body weight (A) and rate of weight accretion relative to change in age (k) for each cow. Actual weight at birth, linear adjusted weights at 200, 365, and 500 d of age, ratios of these weights to mature weight, and height at the hip at 7 yr were analyzed. Beyond 20 mo, weights were adjusted to a constant condition score within breed of sire. Variance and covariance components were derived for breed (sigma 2 b), sires within breed (sigma 2 s), and progeny within sire (sigma 2 w). For all traits, the sigma 2 b estimate of genetic variance ranged from two to four times greater than the variance component for sigma 2 s. Between-breed heritabilities were .91 +/- .27 and .54 +/- .17 for A and k, respectively. Estimates of within-breed heritability for these two traits were .61 +/- .11 and .27 +/- .09. Estimates, both between- and within-breed, of the genetic correlation between A and k were moderate to large and negative; those between A and weights at 200, 365, and 500 d and height at maturity were large and positive. Selection for immediate change in measures of growth would be most effective among breeds. Sufficient direct genetic variation exists between breeds to enhance breed improvement of growth characters through breed substitution. Greater opportunity to alter the shape of the growth curve exists through selection for within-breed selection than through breed substitution. PMID:1894547

  5. Age-Related Differences in the Production of Textual Descriptions

    ERIC Educational Resources Information Center

    Marini, Andrea; Boewe, Anke; Caltagirone, Carlo; Carlomagno, Sergio

    2005-01-01

    Narratives produced by 69 healthy Italian adults were analyzed for age-related changes of microlinguistic, macrolinguistic and informative aspects. The participants were divided into five age groups (20-24, 25-39, 40-59, 60-74, 75-84). One single-picture stimulus and two cartoon sequences were used to elicit three stories per subject. Age-related…

  6. APOLIPOPROTEIN E GENE AND EARLY AGE-RELATED MACULOPATHY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    OBJECTIVE: To examine the association between the apolipoprotein E (APOE) gene and early age-related maculopathy (ARM) in middle-aged persons. DESIGN: Population-based cross-sectional study. PARTICIPANTS: Participants from the Atherosclerosis Risk in Communities Study (n = 10139; age range, 49-73 ye...

  7. The Relative Age Effect among Female Brazilian Youth Volleyball Players

    ERIC Educational Resources Information Center

    Okazaki, Fabio H. A.; Keller, Birgit; Fontana, Fabio E.; Gallagher, Jere D.

    2011-01-01

    In sports, the relative age effect (RAE) refers to performance disadvantages of children born late in the competition year compared to those with birthdays soon after the cutoff date. This effect is derived from age grouping, a strategy commonly used in youth sport programs. The purpose of age grouping is to decrease possible cognitive, physical,…

  8. Aging as an emergent factor that contributes to phenotypic variation in Cryptococcus neoformans.

    PubMed

    Bouklas, Tejas; Fries, Bettina C

    2015-05-01

    Cryptococcus neoformans, similar to other eukaryotes, undergoes replicative aging. Replicative life spans have been determined for clinical C. neoformans strains, and although they are a reproducible trait, life spans vary considerably among strains. C. neoformans has been proposed as an ideal model organism to investigate the contribution of replicative aging in a fungal pathogen population to emerging phenotypic variation during chronic cryptococcal infections. C. neoformans cells of advanced generational age manifest a distinct phenotype; specifically, a larger cell size, a thicker cell wall, drug resistance, as well as resistance to hydrogen peroxide-mediated killing. Consequently, old cells are selected in the host environment during chronic infection and aging could be an unanticipated mechanism of pathogen adaptation that contributes to persistent disease. Aging as a natural process of phenotypic variation should be further studied as it likely is also relevant for other eukaryotic pathogen populations that undergo asymmetric replicative aging. PMID:25307541

  9. Neuroimaging explanations of age-related differences in task performance

    PubMed Central

    Steffener, Jason; Barulli, Daniel; Habeck, Christian; Stern, Yaakov

    2014-01-01

    Advancing age affects both cognitive performance and functional brain activity and interpretation of these effects has led to a variety of conceptual research models without always explicitly linking the two effects. However, to best understand the multifaceted effects of advancing age, age differences in functional brain activity need to be explicitly tied to the cognitive task performance. This work hypothesized that age-related differences in task performance are partially explained by age-related differences in functional brain activity and formally tested these causal relationships. Functional MRI data was from groups of young and old adults engaged in an executive task-switching experiment. Analyses were voxel-wise testing of moderated-mediation and simple mediation statistical path models to determine whether age group, brain activity and their interaction explained task performance in regions demonstrating an effect of age group. Results identified brain regions whose age-related differences in functional brain activity significantly explained age-related differences in task performance. In all identified locations, significant moderated-mediation relationships resulted from increasing brain activity predicting worse (slower) task performance in older but not younger adults. Findings suggest that advancing age links task performance to the level of brain activity. The overall message of this work is that in order to understand the role of functional brain activity on cognitive performance, analysis methods should respect theoretical relationships. Namely, that age affects brain activity and brain activity is related to task performance. PMID:24672481

  10. Age at Natural Menopause and Related Factors in Isfahan, Iran

    PubMed Central

    Golshiri, Parastoo; Abdollahzadeh, Mohammad Reza

    2016-01-01

    Objective This study was aimed to evaluate the age at natural menopause and related factors among women in a population based study in 2015 in Isfahan, Islamic Republic of Iran. Methods In this cross-sectional study 960 menopausal women were selected by cluster sampling. Demographic, socioeconomic, lifestyle behavior and reproductive history aspects were collected using a structured questionnaire. Woman and her husband's educational level and occupation with family income were the variables to construct socioeconomic status using principal component analysis. Results Mean and median of natural menopause age were 48.66 and 48 years, respectively. Women body mass index (BMI) more than 30 kg/m2 had significantly higher menopausal age than women with lower BMI (P value = 0.022). The mean of menopausal age was not statistically significant in regard to marital status, physical activity, smoking status, menarche age, age at first pregnancy and history of abortion. Menopause age with pregnancy numbers and age at last pregnancy had a significant positive association. Women with better socioeconomic status had significantly higher natural menopause age. Multiple linear regression shows significant relationship between lower age at menopause with higher age at marriage, higher number of pregnancy and lower socioeconomic status. Conclusion Age at menopause in our studied sample is similar to previous estimates reported for other Iranian populations. Age at marriage, higher number of pregnancy and lower socioeconomic status were the significant factors in relations to age at menopause.

  11. Relative Age Effects in Dutch Adolescents: Concurrent and Prospective Analyses

    PubMed Central

    Jeronimus, Bertus F.; Stavrakakis, Nikolaos; Veenstra, René; Oldehinkel, Albertine J.

    2015-01-01

    The literature on relative age position effects is rather inconsistent. In this study we examined intra-classroom age position (or relative age) effects on Dutch adolescents’ school progress and performance (as rated by teachers), physical development, temperamental development (fear and frustration), and depressive symptoms, all adjusted for age at the time of measurement. Data were derived from three waves of Tracking Adolescents' Individuals Lives Survey (TRAILS) of 2230 Dutch adolescents (baseline mean age 11.1, SD = 0.6, 51% girls). Albeit relative age predicted school progress (grade retention ORs = 0.83 for each month, skipped grade OR = 1.47, both p<.001), our key observation is the absence of substantial developmental differences as a result of relative age position in Dutch adolescents with a normative school trajectory, in contrast to most literature. For adolescents who had repeated a grade inverse relative age effects were observed, in terms of physical development and school performance, as well as on depressive symptoms, favoring the relatively young. Cross-cultural differences in relative age effect may be partly explained by the decision threshold for grade retention. PMID:26076384

  12. Parainflammation, chronic inflammation, and age-related macular degeneration.

    PubMed

    Chen, Mei; Xu, Heping

    2015-11-01

    Inflammation is an adaptive response of the immune system to noxious insults to maintain homeostasis and restore functionality. The retina is considered an immune-privileged tissue as a result of its unique anatomic and physiologic properties. During aging, the retina suffers from a low-grade chronic oxidative insult, which sustains for decades and increases in level with advancing age. As a result, the retinal innate-immune system, particularly microglia and the complement system, undergoes low levels of activation (parainflammation). In many cases, this parainflammatory response can maintain homeostasis in the healthy aging eye. However, in patients with age-related macular degeneration, this parainflammatory response becomes dysregulated and contributes to macular damage. Factors contributing to the dysregulation of age-related retinal parainflammation include genetic predisposition, environmental risk factors, and old age. Dysregulated parainflammation (chronic inflammation) in age-related macular degeneration damages the blood retina barrier, resulting in the breach of retinal-immune privilege, leading to the development of retinal lesions. This review discusses the basic principles of retinal innate-immune responses to endogenous chronic insults in normal aging and in age-related macular degeneration and explores the difference between beneficial parainflammation and the detrimental chronic inflammation in the context of age-related macular degeneration. PMID:26292978

  13. 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

  14. [Depression in Patients with Age-Related Macular Degeneration].

    PubMed

    Narváez, Yamile Reveiz; Gómez-Restrepo, Carlos

    2012-09-01

    Age-related macular degeneration is a cause for disability in the elderly since it greatly affects their quality of life and increases depression likelihood. This article discusses the negative effect depression has on patients with age-related macular degeneration and summarizes the interventions available for decreasing their depression index. PMID:26572116

  15. Relative Weights of the Backpacks of Elementary-Aged Children

    ERIC Educational Resources Information Center

    Bryant, Benjamin P.; Bryant, Judith B.

    2014-01-01

    The purpose of the study was to describe the range of relative backpack weights of one group of elementary-aged children and the extent to which they exceeded recommended levels. A second purpose was to explore whether gender and age help predict the relative weight of children's backpacks. Ninety-five 8- to 12-year-old elementary school…

  16. Unique Relations of Age and Delinquency with Cognitive Control

    ERIC Educational Resources Information Center

    Iselin, Anne-Marie R.; DeCoster, Jamie

    2012-01-01

    Context processing has significant empirical support as an explanation of age- and psychopathology-related deficiencies in cognitive control. We examined whether context processing generalizes to younger individuals who are in trouble with the law. We tested whether age and delinquency might have unique relations to context processing skills in…

  17. Age- and gender-dependent heterogeneous proportion of variation explained by SNPs in quantitative traits reflecting human health.

    PubMed

    Lee, Dain; Lee, Chaeyoung

    2015-01-01

    Age-related effects are often included as covariates in the analytical model for genome-wide association analysis of quantitative traits reflecting human health. Nevertheless, previous studies have hardly examined the effects of age on the proportion of variation explained by single nucleotide polymorphisms (PVSNP) in these traits. In this study, the PVSNP estimates of body mass index (BMI), waist-to-hip ratio, pulse pressure, high-density lipoprotein cholesterol level, triglyceride level (TG), low-density lipoprotein cholesterol level, and glucose level were obtained from Korean consortium metadata partitioned by gender or by age. Restricted maximum likelihood estimates of the PVSNP were obtained in a mixed model framework. Previous studies using pedigree data suggested possible differential heritability of certain traits with regard to gender, which we observed in our current study (BMI and TG; P < 0.05). However, the PVSNP analysis based on age revealed that, with respect to every trait tested, individuals aged 40 to 49 exhibited significantly lower PVSNP estimates than individuals aged 50 to 59 or 60 to 69 (P < 0.05). The consistent heterogeneous PVSNP with respect to age may be due to degenerated genetic functions in individuals between the ages of 50 and 69. Our results suggest the genetic mechanism of age- and gender-dependent PVSNP of quantitative traits related to human health should be further examined. PMID:25701395

  18. Brain-derived neurotrophic factor is associated with age-related decline in hippocampal volume.

    PubMed

    Erickson, Kirk I; Prakash, Ruchika Shaurya; Voss, Michelle W; Chaddock, Laura; Heo, Susie; McLaren, Molly; Pence, Brandt D; Martin, Stephen A; Vieira, Victoria J; Woods, Jeffrey A; McAuley, Edward; Kramer, Arthur F

    2010-04-14

    Hippocampal volume shrinks in late adulthood, but the neuromolecular factors that trigger hippocampal decay in aging humans remains a matter of speculation. In rodents, brain-derived neurotrophic factor (BDNF) promotes the growth and proliferation of cells in the hippocampus and is important in long-term potentiation and memory formation. In humans, circulating levels of BDNF decline with advancing age, and a genetic polymorphism for BDNF has been related to gray matter volume loss in old age. In this study, we tested whether age-related reductions in serum levels of BDNF would be related to shrinkage of the hippocampus and memory deficits in older adults. Hippocampal volume was acquired by automated segmentation of magnetic resonance images in 142 older adults without dementia. The caudate nucleus was also segmented and examined in relation to levels of serum BDNF. Spatial memory was tested using a paradigm in which memory load was parametrically increased. We found that increasing age was associated with smaller hippocampal volumes, reduced levels of serum BDNF, and poorer memory performance. Lower levels of BDNF were associated with smaller hippocampi and poorer memory, even when controlling for the variation related to age. In an exploratory mediation analysis, hippocampal volume mediated the age-related decline in spatial memory and BDNF mediated the age-related decline in hippocampal volume. Caudate nucleus volume was unrelated to BDNF levels or spatial memory performance. Our results identify serum BDNF as a significant factor related to hippocampal shrinkage and memory decline in late adulthood. PMID:20392958

  19. 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. PMID:22255816

  20. Fruits, Nuts, and Brain Aging: Nutritional Interventions Targeting Age-Related Neuronal and Behavioral Deficits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    By the year 2050, 30% of the total population of the US will be over 65 years of age. As the aged population expands, the economic burden of care and treatment of those with age-related health disorders also increases, necessitating the immediate implementation of therapeutics to prevent or even rev...

  1. Undergraduate Students' Perceptions and Behaviors Related to the Aged and to Aging Processes

    ERIC Educational Resources Information Center

    Van Dussen, Daniel J.; Weaver, Robert R.

    2009-01-01

    Aging education is relatively new to the university, and our understanding of the perspectives students bring to aging populations is correspondingly limited. This investigation surveys 546 students at a midsized, Midwestern university to explore students' views toward elders, toward serving elders, and toward the relevance of aging education for…

  2. Topography of age-related changes in sleep spindles.

    PubMed

    Martin, Nicolas; Lafortune, Marjolaine; Godbout, Jonathan; Barakat, Marc; Robillard, Rebecca; Poirier, Gaétan; Bastien, Célyne; Carrier, Julie

    2013-02-01

    Aging induces multiple changes to sleep spindles, which may hinder their alleged functional role in memory and sleep protection mechanisms. Brain aging in specific cortical regions could affect the neural networks underlying spindle generation, yet the topography of these age-related changes is currently unknown. In the present study, we analyzed spindle characteristics in 114 healthy volunteers aged between 20 and 73 years over 5 anteroposterior electroencephalography scalp derivations. Spindle density, amplitude, and duration were higher in young subjects than in middle-aged and elderly subjects in all derivations, but the topography of age effects differed drastically. Age-related decline in density and amplitude was more prominent in anterior derivations, whereas duration showed a posterior prominence. Age groups did not differ in all-night spindle frequency for any derivation. These results show that age-related changes in sleep spindles follow distinct topographical patterns that are specific to each spindle characteristic. This topographical specificity may provide a useful biomarker to localize age-sensitive changes in underlying neural systems during normal and pathological aging. PMID:22809452

  3. Diurnal variation of tropospheric relative humidity in tropical regions

    NASA Astrophysics Data System (ADS)

    Moradi, Isaac; Arkin, Philip; Ferraro, Ralph; Eriksson, Patrick; Fetzer, Eric

    2016-06-01

    Despite the importance of water vapor especially in the tropical region, the diurnal variations of water vapor have not been completely investigated in the past due to the lack of adequate observations. Measurements from Sondeur Atmosphérique du Profil d'Humidité Intertropicale par Radiométrie (SAPHIR) onboard the low inclination Megha-Tropiques satellite with frequent daily revisits provide a valuable dataset for investigating the diurnal and spatial variation of tropospheric relative humidity in the tropical region. In this study, we first transformed SAPHIR observations into layer-averaged relative humidity, then partitioned the data based on local observation time into 24 bins with a grid resolution of one degree. Afterwards, we fitted Fourier series to the binned data. Finally, the mean, amplitude, and diurnal peak time of relative humidity in tropical regions were calculated for each grid point using either the measurements or Fourier series. The results were separately investigated for different SAPHIR channels as well as for relative humidity with respect to both liquid and ice phases. The results showed that the wet and dry regions are, respectively, associated with convective and subsidence regions which is consistent with the previous studies. The mean tropospheric humidity values reported in this study are generally 10 to 15 % higher than those reported using infrared observations which is because of strict cloud screening for infrared measurements. The results showed a large inhomogeneity in diurnal variation of tropospheric relative humidity in tropical region. The diurnal amplitude was larger over land than over ocean and the oceanic amplitude was larger over convective regions than over subsidence regions. The results showed that the diurnal amplitude is less than 10 % in middle and upper troposphere, but it is up to 30 % in lower troposphere over land. Although the peak of RH generally occurs over night or in early morning, there are several

  4. [Seasonal variations in creole heifer cyclicity: effect of growth, age and emotivity].

    PubMed

    Gauthier, D; Thimonier, J

    1982-01-01

    The ovarian and estrous activities in creole heifers have been studied in Guadeloupe in a tropical environment. We carried out two experiments. In the first one, all the heifers from the research station's herd were blood-sampled twice every 2 months at a 10-day interval to determine their ovarian activity. The observations were ranked in order of ascending live weight, and the percentage of heifers showing ovarian activity was calculated for consecutive 10-kg increments in live weight from 115 to 275 kg. The percentage showing ovarian activity (Y) was subjected to probit transformation and related to live weight (X); probit Y = 12.4 log10 X - 23.7. The equation for observations ranked in order of ascending age and the percentage of heifers showing ovarian activity calculated for age increments over 2 consecutive months was: probit Y = 7.06 log10 X - 3.9. Furthermore, the percentage of cyclic heifers in the herd varied from 40 p. 100 in September 1979 to 0 p. 100 in July 1980 and then to 30 p. 100 in September 1980. The percentage of cyclic heifers at a given period of observation was highly correlated with the mean daily increase in body weight (r = 0.86). In the second experiment, 12 heifers with a high feed level were blood-sampled weekly and checked for estrous daily with an androgenized female with a chin ball mating harness. The mean duration of a "normal cycle" (interval between two estruses: more than 15 but less than 31 days) was 21 days. There was no variation of ovarian activity with the month of the year, but the incidence of silent ovulation was high (23.7 p. 100). The seasonal variation of this percentage is shown. Female emotivity was also an important factor: emotional heifers had a higher percentage of silent ovulations than unemotional heifers (27 vs 17 p. 100) and a smaller mean daily gain (180 vs 280 g). PMID:6891832

  5. 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

  6. Anatomic Alterations in Aging and Age-Related Diseases of the Eye

    PubMed Central

    Grossniklaus, Hans E.; Nickerson, John M.; Edelhauser, Henry F.; Bergman, Louise A. M. K.; Berglin, Lennart

    2013-01-01

    Purpose. We described anatomic age-related changes in the human eye to determine potential areas of investigation that may lead to identifying eyes at risk for age-related disease. Methods. A descriptive review of anatomic changes in the eye related to aging was performed in the context of current areas of investigation. The review was performed specifically for differing anatomic ocular structures, including cornea, trabecular meshwork, lens, uveal tract, Bruch's membrane, retina, RPE, vitreous, sclera, and optic nerve. Results. Age-related changes occur in all ocular tissues. The cornea flattens and there is an attrition of endothelial cells. The shape of the trabecular meshwork changes and there is a loss of trabecular endothelium. The lens grows and becomes cataractous. The ciliary body becomes collagenized, there are choroidal vascular changes, and Bruch's membrane thickens. Retinal vessels become hyalinized and there is a loss of rods before cones in the macula. RPE morphometric changes occur with aging. The vitreous becomes liquefied and there is a loss of vitreous compartmentalization. The sclera becomes rigid and may become calcified. The optic nerve exhibits structural changes with age. Conclusions. There are numerous anatomic age-related changes in the human eye. Current areas of investigation related to these changes include adaptive optics scanning laser ophthalmoscopy imaging of the RPE mosaic in the context of aging, and drug delivery devices that overcome age-related alterations to retinal and macular perfusion. PMID:24335063

  7. Geographic, temporal, and age-specific variation in diets of Glaucous Gulls in western Alaska

    USGS Publications Warehouse

    Schmutz, J.A.; Hobson, K.A.

    1998-01-01

    We collected boluses and food remains of adult Glaucous Gulls (Larus hyperboreus) at or near nests and chicks, and digestive tracts from adults at three sites on the Yukon-Kuskokwim Delta, Alaska that differed in proximity to marine and terrestrial foods. We observed both geographic and temporal variation in diet; gulls consumed proportionately more terrestrial prey after peak hatch in late June, and gulls near the coast consumed proportionately more marine prey than gulls at two inland areas. Goslings occurred in > 60% of all samples from these inland areas. We compared these data to those from a previous study in western Alaska and found no marked differences. Evidence for similar patterns of geographic and temporal variation in diet was found using measurements of stable-carbon and nitrogen isotopes in gull and prey tissues. Stable isotope analysis further revealed that adult gulls consumed proportionately more marine prey (saffron cod, Eleginus gracilis) than they fed to their young. Using isotopic models, we estimated that 7-22% and 10-23% of the diet of adult and juvenile Glaucous Gulls, respectively, was comprised of terrestrial species. In addition to significant age-related variation, dietary estimates varied among geographic areas and between pre- and post-hatch periods. Overall, our isotopic estimates of the contribution of terrestrial prey to the diet of Glaucous Gulls was less than what may be inferred from conventional methods of diet analysis. Our study emphasizes the benefit of combining stable-isotope and conventional analyses to infer temporal and geographic changes in diet of wild birds and other organisms.

  8. Life spanning murine gene expression profiles in relation to chronological and pathological aging in multiple organs.

    PubMed

    Jonker, Martijs J; Melis, Joost P M; Kuiper, Raoul V; van der Hoeven, Tessa V; Wackers, Paul F K; Robinson, Joke; van der Horst, Gijsbertus T J; Dollé, Martijn E T; Vijg, Jan; Breit, Timo M; Hoeijmakers, Jan H J; van Steeg, Harry

    2013-10-01

    Aging and age-related pathology is a result of a still incompletely understood intricate web of molecular and cellular processes. We present a C57BL/6J female mice in vivo aging study of five organs (liver, kidney, spleen, lung, and brain), in which we compare genome-wide gene expression profiles during chronological aging with pathological changes throughout the entire murine life span (13, 26, 52, 78, 104, and 130 weeks). Relating gene expression changes to chronological aging revealed many differentially expressed genes (DEGs), and altered gene sets (AGSs) were found in most organs, indicative of intraorgan generic aging processes. However, only ≤ 1% of these DEGs are found in all organs. For each organ, at least one of 18 tested pathological parameters showed a good age-predictive value, albeit with much inter- and intraindividual (organ) variation. Relating gene expression changes to pathology-related aging revealed correlated genes and gene sets, which made it possible to characterize the difference between biological and chronological aging. In liver, kidney, and brain, a limited number of overlapping pathology-related AGSs were found. Immune responses appeared to be common, yet the changes were specific in most organs. Furthermore, changes were observed in energy homeostasis, reactive oxygen species, cell cycle, cell motility, and DNA damage. Comparison of chronological and pathology-related AGSs revealed substantial overlap and interesting differences. For example, the presence of immune processes in liver pathology-related AGSs that were not detected in chronological aging. The many cellular processes that are only found employing aging-related pathology could provide important new insights into the progress of aging. PMID:23795901

  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. Variation in rubber chemistry and dynamic mechanical properties of the milking liner barrel with age.

    PubMed

    Boast, D; Hale, M; Turner, D; Hillerton, J E

    2008-06-01

    The milking liner is the interface between the milking machine and the cow. Liner properties important to milking performance were investigated for liners of different ages using discriminating tests rather than the normal, rubber-industry quality control-based tests. Large variations in the liner mechanical properties occurred depending on where the sample was taken; stiffness increased 4-fold 40 to 50 mm below the top of the liner. This was related to changes in the chemistry of the rubber created by absorption of milk-derived products (MDP) into the rubber and losses of formulation components, particularly 50% of the plasticizer and all of the antidegradent 40 to 50 mm below the top of the liner, with age and use. The presence of MDP leads to calcium and phosphate deposits on the inner surface of the liner barrel where the MDP was absorbed. The detailed liner properties can be used to explain the forces on the cow's teat and its reactions and effects on milk flow behavior, and to guide future liner development. PMID:18487647

  11. Epigenome-Wide Scans Identify Differentially Methylated Regions for Age and Age-Related Phenotypes in a Healthy Ageing Population

    PubMed Central

    Yang, Tsun-Po; Pidsley, Ruth; Nisbet, James; Glass, Daniel; Mangino, Massimo; Zhai, Guangju; Zhang, Feng; Valdes, Ana; Shin, So-Youn; Dempster, Emma L.; Murray, Robin M.; Grundberg, Elin; Hedman, Asa K.; Nica, Alexandra; Small, Kerrin S.; Dermitzakis, Emmanouil T.; McCarthy, Mark I.; Mill, Jonathan; Spector, Tim D.; Deloukas, Panos

    2012-01-01

    Age-related changes in DNA methylation have been implicated in cellular senescence and longevity, yet the causes and functional consequences of these variants remain unclear. To elucidate the role of age-related epigenetic changes in healthy ageing and potential longevity, we tested for association between whole-blood DNA methylation patterns in 172 female twins aged 32 to 80 with age and age-related phenotypes. Twin-based DNA methylation levels at 26,690 CpG-sites showed evidence for mean genome-wide heritability of 18%, which was supported by the identification of 1,537 CpG-sites with methylation QTLs in cis at FDR 5%. We performed genome-wide analyses to discover differentially methylated regions (DMRs) for sixteen age-related phenotypes (ap-DMRs) and chronological age (a-DMRs). Epigenome-wide association scans (EWAS) identified age-related phenotype DMRs (ap-DMRs) associated with LDL (STAT5A), lung function (WT1), and maternal longevity (ARL4A, TBX20). In contrast, EWAS for chronological age identified hundreds of predominantly hyper-methylated age DMRs (490 a-DMRs at FDR 5%), of which only one (TBX20) was also associated with an age-related phenotype. Therefore, the majority of age-related changes in DNA methylation are not associated with phenotypic measures of healthy ageing in later life. We replicated a large proportion of a-DMRs in a sample of 44 younger adult MZ twins aged 20 to 61, suggesting that a-DMRs may initiate at an earlier age. We next explored potential genetic and environmental mechanisms underlying a-DMRs and ap-DMRs. Genome-wide overlap across cis-meQTLs, genotype-phenotype associations, and EWAS ap-DMRs identified CpG-sites that had cis-meQTLs with evidence for genotype–phenotype association, where the CpG-site was also an ap-DMR for the same phenotype. Monozygotic twin methylation difference analyses identified one potential environmentally-mediated ap-DMR associated with total cholesterol and LDL (CSMD1). Our results suggest that in a

  12. Age-related differences in multiple task monitoring.

    PubMed

    Todorov, Ivo; Del Missier, Fabio; Mäntylä, Timo

    2014-01-01

    Coordinating multiple tasks with narrow deadlines is particularly challenging for older adults because of age related decline in cognitive control functions. We tested the hypothesis that multiple task performance reflects age- and gender-related differences in executive functioning and spatial ability. Young and older adults completed a multitasking session with four monitoring tasks as well as separate tasks measuring executive functioning and spatial ability. For both age groups, men exceeded women in multitasking, measured as monitoring accuracy. Individual differences in executive functioning and spatial ability were independent predictors of young adults' monitoring accuracy, but only spatial ability was related to sex differences. For older adults, age and executive functioning, but not spatial ability, predicted multitasking performance. These results suggest that executive functions contribute to multiple task performance across the adult life span and that reliance on spatial skills for coordinating deadlines is modulated by age. PMID:25215609

  13. Age-Related Psychophysiological Vulnerability to Phenylalanine in Phenylketonuria

    PubMed Central

    Leuzzi, Vincenzo; Mannarelli, Daniela; Manti, Filippo; Pauletti, Caterina; Locuratolo, Nicoletta; Carducci, Carla; Carducci, Claudia; Vanacore, Nicola; Fattapposta, Francesco

    2014-01-01

    Background: Phenylketonuria (PKU) is caused by the inherited defect of the phenylalanine hydroxylase enzyme, which converts phenylalanine (Phe) into tyrosine (Tyr). Neonatal screening programs and early treatment have radically changed the natural history of PKU. Nevertheless, an increased risk of neurocognitive and psychiatric problems in adulthood remains a challenging aspect of the disease. In order to assess the vulnerability of complex skills to Phe, we explored: (a) the effect of a rapid increase in blood Phe levels on event-related potentials (ERP) in PKU subjects during their second decade of life; (b) the association (if existing) between psychophysiological and neurocognitive features. Methods: Seventeen early-treated PKU subjects, aged 10–20, underwent ERP [mismatch negativity, auditory P300, contingent negative variation (CNV), and Intensity Dependence of Auditory Evoked Potentials] recording before and 2 h after an oral loading of Phe. Neurocognitive functioning, historical and concurrent biochemical values of blood Phe, Tyr, and Phe/Tyr ratio, were all included in the statistical analysis. Results: Event-related potential components were normally detected in all the subjects. In subjects younger than 13 CNV amplitude, W2-CNV area, P3b latency, and reaction times in motor responses were negatively influenced by Phe-loading. Independently from the psychophysiological vulnerability, some neurocognitive skills were more impaired in younger patients. No correlation was found between biochemical alterations and neurocognitive and psychophysiological findings. Conclusion: The vulnerability of the emerging neurocognitive functions to Phe suggests a strict metabolic control in adolescents affected by PKU and a neurodevelopmental approach in the study of neurocognitive outcome in PKU. PMID:25003100

  14. Age-Related Differences in Moral Identity across Adulthood

    ERIC Educational Resources Information Center

    Krettenauer, Tobias; Murua, Lourdes Andrea; Jia, Fanli

    2016-01-01

    In this study, age-related differences in adults' moral identity were investigated. Moral identity was conceptualized a context-dependent self-structure that becomes differentiated and (re)integrated in the course of development and that involves a broad range of value-orientations. Based on a cross-sectional sample of 252 participants aged 14 to…

  15. Birth Order, Age-Spacing, IQ Differences, and Family Relations.

    ERIC Educational Resources Information Center

    Pfouts, Jane H.

    1980-01-01

    Very close age spacing was an obstacle to high academic performance for later borns. In family relations and self-esteem, first borns scored better and performed in school as well as their potentially much more able younger siblings, regardless of age spacing. (Author)

  16. The Role of Social Activity in Age-Cognition Relations

    ERIC Educational Resources Information Center

    Soubelet, Andrea

    2013-01-01

    The goal of the current project was to examine whether engaging in social activity may moderate or mediate the relation between age and cognitive functioning. A large age range sample of adults performed a variety of cognitive tests and completed a social activities questionnaire. Results did not support the moderator hypothesis, as age…

  17. Nutritional modulation of age-related macular degeneration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly worldwide. It affects 30-50 million individuals and clinical hallmarks of AMD are observed in at least one third of persons over the age of 75 in industrialized countries (Gehrs et al., 2006). Costs associated wi...

  18. Computer Use and the Relation between Age and Cognitive Functioning

    ERIC Educational Resources Information Center

    Soubelet, Andrea

    2012-01-01

    This article investigates whether computer use for leisure could mediate or moderate the relations between age and cognitive functioning. Findings supported smaller age differences in measures of cognitive functioning for people who reported spending more hours using a computer. Because of the cross-sectional design of the study, two alternative…

  19. Nutritional influences on epigenetics and age-related disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nutritional epigenetics has emerged as a novel mechanism underlying gene–diet interactions, further elucidating the modulatory role of nutrition in aging and age-related disease development. Epigenetics is defined as a heritable modification to the DNA that regulates chromosome architecture and modu...

  20. Genetic Variance in Processing Speed Drives Variation in Aging of Spatial and Memory Abilities

    PubMed Central

    Finkel, Deborah; McArdle, John J.; Reynolds, Chandra A.; Hamagami, Fumiaki; Pedersen, Nancy L.

    2013-01-01

    Previous analyses have identified a genetic contribution to the correlation between declines with age in processing speed and higher cognitive abilities. The goal of the current analysis was to apply the biometric dual change score model to consider the possibility of temporal dynamics underlying the genetic covariance between aging trajectories for processing speed and cognitive abilities. Longitudinal twin data from the Swedish Adoption/Twin Study of Aging, including up to 5 measurement occasions covering a 16-year period, were available from 806 participants ranging in age from 50 to 88 years at the 1st measurement wave. Factors were generated to tap 4 cognitive domains: verbal ability, spatial ability, memory, and processing speed. Model-fitting indicated that genetic variance for processing speed was a leading indicator of variation in age changes for spatial and memory ability, providing additional support for processing speed theories of cognitive aging. PMID:19413434

  1. Age-related changes in the misinformation effect.

    PubMed

    Sutherland, R; Hayne, H

    2001-08-01

    In these experiments, we examined the relation between age-related changes in retention and age-related changes in the misinformation effect. Children (5- and 6- and 11- and 12-year-olds) and adults viewed a video, and their memory was assessed immediately, 1 day, or 6 weeks later (Experiment 1). There were large age-related differences in retention when participants were interviewed immediately and after 1 day, but after the 6-week delay, age-related differences in retention were minimal. In Experiment 2, 11- and 12-year-olds and adults were exposed to neutral, leading, and misleading postevent information 1 day or 6 weeks after they viewed the video. Exposure to misleading information increased the number of commission errors, particularly when participants were asked about peripheral aspects of the video. At both retention intervals, children were more likely than adults to incorporate the misleading postevent information into their subsequent verbal accounts. These findings indicate that age-related changes in the misinformation effect are not predicted by age-related changes in retention. PMID:11511130

  2. BOLD Variability is Related to Dopaminergic Neurotransmission and Cognitive Aging.

    PubMed

    Guitart-Masip, Marc; Salami, Alireza; Garrett, Douglas; Rieckmann, Anna; Lindenberger, Ulman; Bäckman, Lars

    2016-05-01

    Dopamine (DA) losses are associated with various aging-related cognitive deficits. Typically, higher moment-to-moment brain signal variability in large-scale patterns of voxels in neocortical regions is linked to better cognitive performance and younger adult age, yet the physiological mechanisms regulating brain signal variability are unknown. We explored the relationship among adult age, DA availability, and blood oxygen level-dependent (BOLD) signal variability, while younger and older participants performed a spatial working memory (SWM) task. We quantified striatal and extrastriatal DA D1 receptor density with [(11)C]SCH23390 and positron emission tomography in all participants. We found that BOLD variability in a neocortical region was negatively related to age and positively related to SWM performance. In contrast, BOLD variability in subcortical regions and bilateral hippocampus was positively related to age and slower responses, and negatively related to D1 density in caudate and dorsolateral prefrontal cortex. Furthermore, BOLD variability in neocortical regions was positively associated with task-related disengagement of the default-mode network, a network whose activation needs to be suppressed for efficient SWM processing. Our results show that age-related DA losses contribute to changes in brain signal variability in subcortical regions and suggest a potential mechanism, by which neocortical BOLD variability supports cognitive performance. PMID:25750252

  3. Aging-related episodic memory decline: are emotions the key?

    PubMed Central

    Kinugawa, Kiyoka; Schumm, Sophie; Pollina, Monica; Depre, Marion; Jungbluth, Carolin; Doulazmi, Mohamed; Sebban, Claude; Zlomuzica, Armin; Pietrowsky, Reinhard; Pause, Bettina; Mariani, Jean; Dere, Ekrem

    2013-01-01

    Episodic memory refers to the recollection of personal experiences that contain information on what has happened and also where and when these events took place. Episodic memory function is extremely sensitive to cerebral aging and neurodegerative diseases. We examined episodic memory performance with a novel test in young (N = 17, age: 21–45), middle-aged (N = 16, age: 48–62) and aged but otherwise healthy participants (N = 8, age: 71–83) along with measurements of trait and state anxiety. As expected we found significantly impaired episodic memory performance in the aged group as compared to the young group. The aged group also showed impaired working memory performance as well as significantly decreased levels of trait anxiety. No significant correlation between the total episodic memory and trait or state anxiety scores was found. The present results show an age-dependent episodic memory decline along with lower trait anxiety in the aged group. Yet, it still remains to be determined whether this difference in anxiety is related to the impaired episodic memory performance in the aged group. PMID:23378831

  4. Relative weights of the backpacks of elementary-aged children.

    PubMed

    Bryant, Benjamin P; Bryant, Judith B

    2014-02-01

    The purpose of the study was to describe the range of relative backpack weights of one group of elementary-aged children and the extent to which they exceeded recommended levels. A second purpose was to explore whether gender and age help predict the relative weight of children's backpacks. Ninety-five 8- to 12-year-old elementary school students (56% girls; 88% car or bus riders) participated. Their school backpacks were weighed, and their age, gender, and mode of transportation to school were recorded. Only 40% of the sample carried backpacks that were less than 10% of their body weights. Five percent of the students' backpacks exceeded 20% of their body weights. Neither age group nor gender significantly predicted relative backpack weight or relative weight levels. Recommendations are made for ways to reduce the weight these young children carry. PMID:23811534

  5. Relative age effect revisited: findings from the dance domain.

    PubMed

    van Rossum, Jacques H A

    2006-04-01

    The relative age effect is a worldwide phenomenon. While there is solid empirical evidence for the existence in sports like soccer and ice hockey, there are also some findings indicating the absence of the phenomenon. In an earlier study, no support was found with Dutch top-level athletes in table tennis and in volleyball. The explanation was that in athletic tasks which depend heavily on the technical ability (or motor skill) of the participant, a relative age effect will not be observed. In the present study this supposition was tested again with three samples of Dutch preprofessional dance students (overall number of subjects: 546). Again no support was obtained for the relative age effect. Therefore, a case is being built that the relative age effect is not an omnipresent phenomenon. PMID:16826648

  6. THE IMPACT OF ENHANCED He AND CNONa ABUNDANCES ON GLOBULAR CLUSTER RELATIVE AGE-DATING METHODS

    SciTech Connect

    MarIn-Franch, Antonio; Aparicio, Antonio; Cassisi, Santi; Pietrinferni, Adriano E-mail: antapaj@iac.e E-mail: pietrinferni@oa-teramo.inaf.i

    2010-05-10

    The impact that unrecognized differences in the chemical patterns of Galactic globular clusters (GGCs) have on their relative age determinations is studied. The two most widely used relative age-dating methods, horizontal and vertical, together with the more recent relative MS-fitting method, were carefully analyzed on a purely theoretical basis. The BaSTI library was adopted to perform the present analysis. We find that relative ages derived using the horizontal and vertical methods are largely dependent on the initial He content and heavy element distribution. Unrecognized cluster-to-cluster chemical abundance differences can lead to an error in the derived relative ages as large as {approx}0.5 (or {approx}6 Gyr if an age of 12.8 Gyr is adopted for normalization) and even larger for some extreme cases. It is shown that the relative MS-fitting method is by far the age-dating technique for which undetected cluster-to-cluster differences in the He abundance have less impact. Present results are used in order to pose constraints on the maximum possible spread in the He and CNONa elements abundances on the basis of the estimates-taken from the literature-of the GGCs relative age dispersion obtained with the various relative age-dating techniques. Finally, it is shown that the age-metallicity relation found for young GGCs by the GC Treasury program is a real age sequence and cannot be produced by variations in the He and/or heavy element distribution.

  7. Macular xanthophylls, lipoprotein-related genes, and age-related macular degeneration1234

    PubMed Central

    Koo, Euna; Neuringer, Martha; SanGiovanni, John Paul

    2014-01-01

    Plant-based macular xanthophylls (MXs; lutein and zeaxanthin) and the lutein metabolite meso-zeaxanthin are the major constituents of macular pigment, a compound concentrated in retinal areas that are responsible for fine-feature visual sensation. There is an unmet need to examine the genetics of factors influencing regulatory mechanisms and metabolic fates of these 3 MXs because they are linked to processes implicated in the pathogenesis of age-related macular degeneration (AMD). In this work we provide an overview of evidence supporting a molecular basis for AMD-MX associations as they may relate to DNA sequence variation in AMD- and lipoprotein-related genes. We recognize a number of emerging research opportunities, barriers, knowledge gaps, and tools offering promise for meaningful investigation and inference in the field. Overviews on AMD- and high-density lipoprotein (HDL)–related genes encoding receptors, transporters, and enzymes affecting or affected by MXs are followed with information on localization of products from these genes to retinal cell types manifesting AMD-related pathophysiology. Evidence on the relation of each gene or gene product with retinal MX response to nutrient intake is discussed. This information is followed by a review of results from mechanistic studies testing gene-disease relations. We then present findings on relations of AMD with DNA sequence variants in MX-associated genes. Our conclusion is that AMD-associated DNA variants that influence the actions and metabolic fates of HDL system constituents should be examined further for concomitant influence on MX absorption, retinal tissue responses to MX intake, and the capacity to modify MX-associated factors and processes implicated in AMD pathogenesis. PMID:24829491

  8. The role of mitochondria in age-related hearing loss.

    PubMed

    Chen, Hengchao; Tang, Jianguo

    2014-02-01

    Age-related hearing loss (ARHL), the hearing loss associated with aging, is a vital problem in present society. The severity of hearing loss is possibly associated with the degeneration of cochlear cells. Mitochondria play a key role in the energy supply, cellular redox homeostasis, signaling, and regulation of programmed cell death. In this review, we focus on the central role of mitochondria in ARHL. The mitochondrial redox imbalance and mitochondrial DNA mutation might collaboratively involve in the process of cochlear senescence in response to the aging stress. Subsequent responses, including alteration of mitochondrial biogenesis, mitophagy, apoptosis and paraptosis, participate in the aging process from different respects. PMID:24202185

  9. Spectral evaluation of aging effects on blood pressure and heart rate variations in healthy subjects.

    PubMed

    Singh, D; Vinod, K; Saxena, S C; Deepak, K K

    2006-01-01

    The background to heart rate variability (HRV) and blood pressure variability (BPV), and their determinants and physiological correlates, remain obscure. The impact of age must be taken into account if HRV and BPV are used for predictive purposes in clinical settings. Healthy subjects show wide inter-individual variation in their heart rate behaviour and the factors affecting heart rate dynamics are not well known. This paper has undertaken to evaluate heart rate variability (HRV) and baroreflex sensitivity (BRS) in a random sample of subjects without evidence of heart disease, and to estimate the relation of HRV and BPV behaviour to age. The aim of this study was to analyse the effects of ageing on HRV and BPV for simultaneous recordings of electrocardiograph (ECG) and blood pressure (BP) signals at rest in healthy subjects. We studied eight young (21-34 years old) and eight elderly (68-85 years old) rigorously screened subjects from the Fantasia Database to make the reproducibility and comparability of the results more extensive. Time- and frequency-domain analysis of HRV and BPV was performed on 5-minute ectopic-free recordings. BRS on the heart was estimated by frequency-domain analysis of spontaneous variability of systolic blood pressure (SBP) and RR interval. It has been observed that compared to young the elderly subjects have (i) diminished HRV; (ii) a shift in the power spectral density and median frequency to low frequency side for HRV and to higher frequency side for BPV; and (iii) increased low-frequency alpha index and decreased high-frequency alpha index of BRS with overall alpha index augmented. The results convey that normal ageing in the absence of disease is associated with lesser parasympathetic regulation of heart rate. Thus it is concluded that the age is an important factor to be considered for prognosis and diagnosis by HRV and BPV. For reliable clinical applications, more research needs to be done on a broad spectrum of subjects. In

  10. Do weight categories prevent athletes from relative age effect?

    PubMed

    Delorme, Nicolas

    2014-01-01

    The aim of this study was to investigate whether weight categories prevent young athletes from being exposed to a relative age effect. The dates of birth of all French female (n = 727) and male (n = 5440) amateur boxers who participated in the 2010-2011 season were collected from the federation database. The dates of birth of all French male professional boxers (n = 354) were also collected. The results show an absence of a relative age effect among French female and male amateur boxers. The results also show an absence of this phenomenon among French male professional boxers. The male 18-18+ age category reveal an inverse relative age effect. This inverse relative age effect might be interpreted as the result of a strategic adaptation from relatively younger children who shift from one sport to another where there are weight categories in order to ensure fair competition. The results of this study suggest that the weight category system is a possible solution within the relative age effect phenomenon. PMID:23879217

  11. Cultural Orientation in Asian American Adolescents: Variation by Age and Ethnic Density

    ERIC Educational Resources Information Center

    Ying, Yu-Wen; Han, Meekyung; Wong, Sandra L.

    2008-01-01

    The study assessed variation in cultural orientation among Asian American adolescents by age and ethnic density in the community. A total of 128 students at a public high school in Oakland, California, participated in the study. Of these early and middle adolescents, 86 were Chinese American and 42 were Southeast Asian American. They completed the…

  12. Aging assessment of reactor instrumentation and protection system components. Aging-related operating experiences

    SciTech Connect

    Gehl, A.C.; Hagen, E.W.

    1992-07-01

    A study of the aging-related operating experiences throughout a five-year period (1984--1988) of six generic instrumentation modules (indicators, sensors, controllers, transmitters, annunciators, and recorders) was performed as a part of the Nuclear Plant Aging Research Program. The effects of aging from operational and environmental stressors were characterized from results depicted in Licensee Event Reports (LERs). The data are graphically displayed as frequency of events per plant year for operating plant ages from 1 to 28 years to determine aging-related failure trend patterns. Three main conclusions were drawn from this study: (1) Instrumentation and control (I&C) modules make a modest contribution to safety-significant events: 17% of LERs issued during 1984--1988 dealt with malfunctions of the six I&C modules studied, and 28% of the LERs dealing with these I&C module malfunctions were aging related (other studies show a range 25--50%); (2) Of the six modules studied, indicators, sensors, and controllers account for the bulk (83%) of aging-related failures; and (3) Infant mortality appears to be the dominant aging-related failure mode for most I&C module categories (with the exception of annunciators and recorders, which appear to fail randomly).

  13. The suprachiasmatic nucleus: age-related decline in biological rhythms.

    PubMed

    Nakamura, Takahiro J; Takasu, Nana N; Nakamura, Wataru

    2016-09-01

    Aging is associated with changes in sleep duration and quality, as well as increased rates of pathologic/disordered sleep. While several factors contribute to these changes, emerging research suggests that age-related changes in the mammalian central circadian clock within the suprachiasmatic nucleus (SCN) may be a key factor. Prior work from our group suggests that circadian output from the SCN declines because of aging. Furthermore, we have previously observed age-related infertility in female mice, caused by a mismatch between environmental light-dark cycles and the intrinsic, internal biological clocks. In this review, we address regulatory mechanisms underlying circadian rhythms in mammals and summarize recent literature describing the effects of aging on the circadian system. PMID:26915078

  14. Polysaccharides from Medicinal Herbs As Potential Therapeutics for Aging and Age-Related Neurodegeneration

    PubMed Central

    Li, Haifeng; Ma, Fangli; Hu, Minghua; Xiao, Lingyun; Zhang, Ju; Xiang, Yanxia

    2014-01-01

    Abstract Recent studies have uncovered important aging clues, including free radicals, inflammation, telomeres, and life span pathways. Strategies to regulate aging-associated signaling pathways are expected to be effective in the delay and prevention of age-related disorders. For example, herbal polysaccharides with considerable anti-oxidant and anti-inflammation capacities have been shown to be beneficial in aging and age-related neurodegenerative diseases. Polysaccharides capable of reducing cellular senescence and modulating life span via telomere and insulin pathways have also been found to have the potential to inhibit protein aggregation and aggregation-associated neurodegeneration. Here we present the current status of polysaccharides in anti-aging and anti-neurodegenerative studies. PMID:24125569

  15. [The genetic variability of complement system in pathogenesis of age-related macular degeneration].

    PubMed

    Kubicka-Trząska, Agnieszka; Karska-Basta, Izabella; Dziedzina, Sylwia; Sanak, Marek

    2015-01-01

    Age-related macular degeneration is the leading cause of irreversible central vision impairment in people aged over 50 in developed countries. Age-related macular degeneration is a complex disease derived from environmental, immune and genetic factors. The complement pathway has been implicated in the pathogenesis of many diseases. Recently, variants in several genes, such as complement H (CFH), complement factor B (CFB), complement 2 (C2), and complement 3 (C3), encoding complement pathway proteins, have been identified as associated with age-related macular degeneration. However, the associations between these genes and age-related macular degeneration varied due to genetic variation within populations and various ethnics groups. The strongest association was found between the age-related macular degeneration and SNP Y402H rs 1061170 variant of CFH gene, which is present in 30% to 50% of age-related macular degeneration patients in Caucasian population and which is a risk factor for the development of age-related macular degeneration. Cohort studies showed that polymorphism Arg102Gly (SNP rs 2230199) of C3 protein could serve as a high-risk genetic marker for the development of age-related macular degeneration. Other rare variants of C3 (Lys155Gln, Lys65Gln, Arg735Trp, Ser1619Arg), may also be associated with a high incidence of age-related macular degeneration in some ethnic groups. A protective haplotype of variants E318D and IVS10 in the C2 gene as well as L9H and R320 in the BF were associated with age-related macular degeneration but only in Caucasians. The genetic findings in age-related macular degeneration patients stress the importance of detailed phenotyping to identify age-related macular degeneration subtypes, which may be associated with the presence of different polymorphisms and various environmental risk factors in any population. Further studies may be helpful to improve the effectiveness of prophylaxis and therapeutic options in age-related

  16. PPARα agonist, fenofibrate, ameliorates age-related renal injury.

    PubMed

    Kim, Eun Nim; Lim, Ji Hee; Kim, Min Young; Kim, Hyung Wook; Park, Cheol Whee; Chang, Yoon Sik; Choi, Bum Soon

    2016-08-01

    The kidney ages quickly compared with other organs. Expression of senescence markers reflects changes in the energy metabolism in the kidney. Two important issues in aging are mitochondrial dysfunction and oxidative stress. Peroxisome proliferator-activated receptor α (PPARα) is a member of the ligand-activated nuclear receptor superfamily. PPARα plays a major role as a transcription factor that regulates the expression of genes involved in various processes. In this study, 18-month-old male C57BL/6 mice were divided into two groups, the control group (n=7) and the fenofibrate-treated group (n=7) was fed the normal chow plus fenofibrate for 6months. The PPARα agonist, fenofibrate, improved renal function, proteinuria, histological change (glomerulosclerosis and tubular interstitial fibrosis), inflammation, and apoptosis in aging mice. This protective effect against age-related renal injury occurred through the activation of AMPK and SIRT1 signaling. The activation of AMPK and SIRT1 allowed for the concurrent deacetylation and phosphorylation of their target molecules and decreased the kidney's susceptibility to age-related changes. Activation of the AMPK-FOXO3a and AMPK-PGC-1α signaling pathways ameliorated oxidative stress and mitochondrial dysfunction. Our results suggest that activation of PPARα and AMPK-SIRT1 signaling may have protective effects against age-related renal injury. Pharmacological targeting of PPARα and AMPK-SIRT1 signaling molecules may prevent or attenuate age-related pathological changes in the kidney. PMID:27130813

  17. 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

  18. Cellular senescence in aging and age-related disease: from mechanisms to therapy

    PubMed Central

    Childs, Bennett G; Durik, Matej; Baker, Darren J; van Deursen, Jan M

    2016-01-01

    Cellular senescence, a process that imposes permanent proliferative arrest on cells in response to various stressors, has emerged as a potentially important contributor to aging and age-related disease, and it is an attractive target for therapeutic exploitation. A wealth of information about senescence in cultured cells has been acquired over the past half century; however, senescence in living organisms is poorly understood, largely because of technical limitations relating to the identification and characterization of senescent cells in tissues and organs. Furthermore, newly recognized beneficial signaling functions of senescence suggest that indiscriminately targeting senescent cells or modulating their secretome for anti-aging therapy may have negative consequences. Here we discuss current progress and challenges in understanding the stressors that induce senescence in vivo, the cell types that are prone to senesce, and the autocrine and paracrine properties of senescent cells in the contexts of aging and age-related diseases as well as disease therapy. PMID:26646499

  19. Can DRYAD explain age-related associative memory deficits?

    PubMed

    Smyth, Andrea C; Naveh-Benjamin, Moshe

    2016-02-01

    A recent interesting theoretical account of aging and memory judgments, the DRYAD (density of representations yields age-related deficits; Benjamin, 2010; Benjamin, Diaz, Matzen, & Johnson, 2012), attributes the extensive findings of disproportional age-related deficits in memory for source, context, and associations, to a global decline in memory fidelity. It is suggested that this global deficit, possibly due to a decline in attentional processes, is moderated by weak representation of contextual information to result in disproportional age-related declines. In the current article, we evaluate the DRYAD model, comparing it to specific age-related deficits theories, in particular, the ADH (associative deficit hypothesis, Naveh-Benjamin, 2000). We question some of the main assumptions/hypotheses of DRYAD in light of data reported in the literature, and we directly assess the role of attention in age-related deficits by manipulations of divided attention and of the instructions regarding what to pay attention to in 2 experiments (one from the literature and a new one). The results of these experiments fit the predictions of the ADH and do not support the main assumption/hypotheses of DRYAD. PMID:25961878

  20. Lens opacity based modelling of the age-related straylight increase.

    PubMed

    Rozema, Jos J; Sanchez, Victoria; Artal, Natalia; Gramajo, Ana L; Torres, Eduardo; Luna, Jose D; Iribarren, Rafael; Tassignon, Marie-José; Juarez, Claudio P

    2015-12-01

    This work studies ethnic and geographical differences in the age-related straylight increase by means of a stochastic model and unpublished lens opacity data of 559 residents of Villa Maria (Argentina), as well as data of 912 Indonesian subjects published previously by Husain et al. For both cohorts the prevalence of each type and grade of lens opacity was determined as a function of age, from which a stochastic model was derived capable of simulating the lens opacity prevalence for both populations. These simulated lens opacity data were then converted to estimated straylight by means of an equation derived from previously recorded data of 107 eyes with varying degrees of cataract. Based on these opacity templates 2500 random sets of subject age and lens opacity data were generated by the stochastic model for each dataset, from which estimated straylight could be calculated. For the Argentinian data the estimated straylight was found to closely resemble the published models for age-related straylight increase. For younger eyes the straylight variation of the model was the same as what was previously published (in both cases ±0.200logunits), which doubled in size for older eyes. For the Indonesian data, however, this age-related straylight increase was found to be fundamentally different from the published age model. This suggests that current normative curves for age-related straylight increase may not always be appropriate for non-European populations, and that the inter-individual straylight variations in young, healthy eyes may possibly be due to variations in lens opacities. PMID:26459146

  1. Aging Affects Neural Synchronization to Speech-Related Acoustic Modulations

    PubMed Central

    Goossens, Tine; Vercammen, Charlotte; Wouters, Jan; van Wieringen, Astrid

    2016-01-01

    As people age, speech perception problems become highly prevalent, especially in noisy situations. In addition to peripheral hearing and cognition, temporal processing plays a key role in speech perception. Temporal processing of speech features is mediated by synchronized activity of neural oscillations in the central auditory system. Previous studies indicate that both the degree and hemispheric lateralization of synchronized neural activity relate to speech perception performance. Based on these results, we hypothesize that impaired speech perception in older persons may, in part, originate from deviances in neural synchronization. In this study, auditory steady-state responses that reflect synchronized activity of theta, beta, low and high gamma oscillations (i.e., 4, 20, 40, and 80 Hz ASSR, respectively) were recorded in young, middle-aged, and older persons. As all participants had normal audiometric thresholds and were screened for (mild) cognitive impairment, differences in synchronized neural activity across the three age groups were likely to be attributed to age. Our data yield novel findings regarding theta and high gamma oscillations in the aging auditory system. At an older age, synchronized activity of theta oscillations is increased, whereas high gamma synchronization is decreased. In contrast to young persons who exhibit a right hemispheric dominance for processing of high gamma range modulations, older adults show a symmetrical processing pattern. These age-related changes in neural synchronization may very well underlie the speech perception problems in aging persons. PMID:27378906

  2. Age-related Cardiac Disease Model of Drosophila

    PubMed Central

    Ocorr, Karen; Akasaka, Takeshi; Bodmer, Rolf

    2007-01-01

    We have begun to study the genetic basis of deterioration of cardiac function in the fruit fly Drosophila melanogaster as an age-related cardiac disease model. For this purpose we have developed heart function assays in Drosophila and found that the fly's cardiac performance, as that of the human heart, deteriorates with age: aging fruit flies exhibit a progressive increase in electrical pacing-induced heart failure as well as in arrhythmias. The insulin receptor and associated pathways have a dramatic and heart-autonomous influence on age-related cardiac performance in flies, suggestive of potentially similar mechanisms in regulating cardiac aging in vertebrates. Compromised KCNQ and KATP ion channel functions also seem to contribute to the decline in heart performance in aging flies, suggesting that the corresponding vertebrate gene functions may similarly decline with age, in addition to their conserved role in protecting against arrhythmias and hypoxia/ischemia, respectively. The fly heart is thus emerging as a promising genetic model for studying the age-dependent decline in organ function. PMID:17125816

  3. 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.

  4. Age-related changes in the adaptability of neuromuscular output.

    PubMed

    Morrison, Steven; Sosnoff, Jacob J

    2009-05-01

    The aging process is associated with a general decline in biological function. One characteristic that researchers believe represents this diminished functioning of the aging neuromuscular system is increased physiological tremor. The present study is constructed to assess what age-related differences exist in the dynamics of tremor and forearm muscle activity under postural conditions in which the number of arm segments involved in the task was altered. The authors predicted that any alteration in the tremor or electromyographic (EMG) output of these two groups would provide a clearer understanding of the differential effects of aging or task dynamics on physiological function. Results reveal no age-related differences in finger tremor or forearm extensor muscle EMG activity under conditions in which participants were only required to extend their index finger against gravity. However, when participants had to hold their entire upper limb steady against gravity, the authors observed significant increases in forearm EMG activity, finger-tremor amplitude, power in the 8-12-Hz range, and signal regularity between the 2 age groups. The selective changes in signal regularity, EMG activity, and 8-12-Hz tremor amplitude under more challenging postural demands support the view that the age-related changes in neuromuscular dynamics are not fully elucidated when single task demands are utilized. PMID:19366659

  5. Dietary Approaches that Delay Age-Related Diseases

    PubMed Central

    Everitt, Arthur V; Hilmer, Sarah N; Brand-Miller, Jennie C; Jamieson, Hamish A; Truswell, A Stewart; Sharma, Anita P; Mason, Rebecca S; Morris, Brian J; Le Couteur, David G

    2006-01-01

    Reducing food intake in lower animals such as the rat decreases body weight, retards many aging processes, delays the onset of most diseases of old age, and prolongs life. A number of clinical trials of food restriction in healthy adult human subjects running over 2–15 years show significant reductions in body weight, blood cholesterol, blood glucose, and blood pressure, which are risk factors for the development of cardiovascular disease and diabetes. Lifestyle interventions that lower energy balance by reducing body weight such as physical exercise can also delay the development of diabetes and cardiovascular disease. In general, clinical trials are suggesting that diets high in calories or fat along with overweight are associated with increased risk for cardiovascular disease, type 2 diabetes, some cancers, and dementia. There is a growing literature indicating that specific dietary constituents are able to influence the development of age-related diseases, including certain fats (trans fatty acids, saturated, and polyunsaturated fats) and cholesterol for cardiovascular disease, glycemic index and fiber for diabetes, fruits and vegetables for cardiovascular disease, and calcium and vitamin D for osteoporosis and bone fracture. In addition, there are dietary compounds from different functional foods, herbs, and neutraceuticals such as ginseng, nuts, grains, and polyphenols that may affect the development of age-related diseases. Long-term prospective clinical trials will be needed to confirm these diet—disease relationships. On the basis of current research, the best diet to delay age-related disease onset is one low in calories and saturated fat and high in wholegrain cereals, legumes, fruits and vegetables, and which maintains a lean body weight. Such a diet should become a key component of healthy aging, delaying age-related diseases and perhaps intervening in the aging process itself. Furthermore, there are studies suggesting that nutrition in childhood

  6. Dietary approaches that delay age-related diseases.

    PubMed

    Everitt, Arthur V; Hilmer, Sarah N; Brand-Miller, Jennie C; Jamieson, Hamish A; Truswell, A Stewart; Sharma, Anita P; Mason, Rebecca S; Morris, Brian J; Le Couteur, David G

    2006-01-01

    Reducing food intake in lower animals such as the rat decreases body weight, retards many aging processes, delays the onset of most diseases of old age, and prolongs life. A number of clinical trials of food restriction in healthy adult human subjects running over 2-15 years show significant reductions in body weight, blood cholesterol, blood glucose, and blood pressure, which are risk factors for the development of cardiovascular disease and diabetes. Lifestyle interventions that lower energy balance by reducing body weight such as physical exercise can also delay the development of diabetes and cardiovascular disease. In general, clinical trials are suggesting that diets high in calories or fat along with overweight are associated with increased risk for cardiovascular disease, type 2 diabetes, some cancers, and dementia. There is a growing literature indicating that specific dietary constituents are able to influence the development of age-related diseases, including certain fats (trans fatty acids, saturated, and polyunsaturated fats) and cholesterol for cardiovascular disease, glycemic index and fiber for diabetes, fruits and vegetables for cardiovascular disease, and calcium and vitamin D for osteoporosis and bone fracture. In addition, there are dietary compounds from different functional foods, herbs, and neutraceuticals such as ginseng, nuts, grains, and polyphenols that may affect the development of age-related diseases. Long-term prospective clinical trials will be needed to confirm these diet-disease relationships. On the basis of current research, the best diet to delay age-related disease onset is one low in calories and saturated fat and high in wholegrain cereals, legumes, fruits and vegetables, and which maintains a lean body weight. Such a diet should become a key component of healthy aging, delaying age-related diseases and perhaps intervening in the aging process itself. Furthermore, there are studies suggesting that nutrition in childhood and

  7. The Relation Between Instrumental Musical Activity and Cognitive Aging

    PubMed Central

    Hanna-Pladdy, Brenda; MacKay, Alicia

    2015-01-01

    Objective Intensive repetitive musical practice can lead to bilateral cortical reorganization. However, whether musical sensorimotor and cognitive abilities transfer to nonmusical cognitive abilities that are maintained throughout the life span is unclear. In an attempt to identify modifiable lifestyle factors that may potentially enhance successful aging, we evaluated the association between musical instrumental participation and cognitive aging. Method Seventy older healthy adults (ages 60–83) varying in musical activity completed a comprehensive neuropsychological battery. The groups (nonmusicians, low and high activity musicians) were matched on age, education, history of physical exercise, while musicians were matched on age of instrumental acquisition and formal years of musical training. Musicians were classified in the low (1–9 years) or high (>10 years) activity group based on years of musical experience throughout their life span. Results The results of this preliminary study revealed that participants with at least 10 years of musical experience (high activity musicians) had better performance in nonverbal memory (η2 = .106), naming (η2 = .103), and executive processes (η2 = .131) in advanced age relative to nonmusicians. Several regression analyses evaluated how years of musical activity, age of acquisition, type of musical training, and other variables predicted cognitive performance. Conclusions These correlational results suggest a strong predictive effect of high musical activity throughout the life span on preserved cognitive functioning in advanced age. A discussion of how musical participation may enhance cognitive aging is provided along with other alternative explanations. PMID:21463047

  8. Caspase-2 Deficiency Enhances Aging-Related Traits in Mice

    PubMed Central

    Zhang, Yingpei; Padalecki, Susan S; Chaudhuri, Asish R; Waal, Eric De; Goins, Beth A; Grubbs, Barry; Ikeno, Yuji; Richardson, Arlan; Mundy, Gregory R; Herman, Brian

    2007-01-01

    Alteration of apoptotic activity has been observed in a number of tissues in aging mammals, but it remains unclear whether and/or how apoptosis may affect aging. Caspase-2 is a member of the cysteine protease family that plays a critical role in apoptosis. To understand the impact of compromised apoptosis function on mammalian aging, we conducted a comparative study on caspase-2 deficient mice and their wild-type littermates with a specific focus on the aging-related traits at advanced ages. We found that caspase-2 deficiency enhanced a number of traits commonly seen in premature aging animals. Loss of caspase-2 was associated with shortened maximum lifespan, impaired hair growth, increased bone loss, and reduced body fat content. In addition, we found that the livers of caspase-2 deficient mice had higher levels of oxidized proteins than those of age-matched wild-type mice, suggesting that caspase-2 deficiency compromised the animal's ability to clear oxidatively damaged cells. Collectively, these results suggest that caspase-2 deficiency affects aging in the mice. This study thus demonstrates for the first time that disruption of a key apoptotic gene has a significant impact on aging. PMID:17188333

  9. eNOS-uncoupling in age-related erectile dysfunction

    PubMed Central

    Johnson, JM; Bivalacqua, TJ; Lagoda, GA; Burnett, AL; Musicki, B

    2011-01-01

    Aging is associated with ED. Although age-related ED is attributed largely to increased oxidative stress and endothelial dysfunction in the penis, the molecular mechanisms underlying this effect are not fully defined. We evaluated whether endothelial nitric oxide synthase (eNOS) uncoupling in the aged rat penis is a contributing mechanism. Correlatively, we evaluated the effect of replacement with eNOS cofactor tetrahydrobiopterin (BH4) on erectile function in the aged rats. Male Fischer 344 ‘young’ (4-month-old) and ‘aged’ (19-month-old) rats were treated with a BH4 precursor sepiapterin (10 mg/kg intraperitoneally) or vehicle for 4 days. After 1-day washout, erectile function was assessed in response to electrical stimulation of the cavernous nerve. Endothelial dysfunction (eNOS uncoupling) and oxidative stress (thiobarbituric acid reactive substances, TBARS) were measured by conducting western blot in penes samples. Erectile response was significantly reduced in aged rats, whereas eNOS uncoupling and TBARS production were significantly increased in the aged rat penis compared with young rats. Sepiapterin significantly improved erectile response in aged rats and prevented increase in TBARS production, but did not affect eNOS uncoupling in the penis of aged rats. These findings suggest that aging induces eNOS uncoupling in the penis, resulting in increased oxidative stress and ED. PMID:21289638

  10. Streamwater ages derived from tritium show power law variation with discharge like silica concentrations

    NASA Astrophysics Data System (ADS)

    Stewart, Michael; Morgenstern, Uwe

    2013-04-01

    Understanding runoff generation is important for management of freshwater systems. Determining transit time distributions of streamwaters and how they change with discharge gives information on the flowpaths and recharge sources of streams - vital information for determining the responses of streams to stressors such as pollution, landuse change, or climate change. This work takes a first look at unique information on how transit time distributions change with discharge in some New Zealand catchments. Transit time distributions of streamwaters have been determined from tritium measurements on single samples in this work. This allows changes with stream discharge to be observed, in contrast to previous isotope studies which have given averaged transit time distributions based on series of samples. In addition, tritium reveals the wide spectrum of ages present in streams whereas oxygen-18 or chloride variations only show the younger ages (Stewart et al., 2010). It was found that the mean transit time (MTT) data could be reasonably represented by straight lines in log-log plots, indicating power law relationships between MTT and discharge. Similar power law behaviour has been observed for the rock forming elements such as silica in streamwaters (Godsey et al., 2009). Case studies are presented for two New Zealand catchments, both with volcanic ash substrates. Toenepi is a dairy catchment near Hamilton, which shows well-constrained power law relationships between MTT and discharge, and between silica concentration and discharge (Morgenstern et al., 2010). Baseflow MTTs vary from 2.5 to 157 years. Tutaeuaua is a pastoral farming catchment near Taupo. Results for nested catchments along the stream also show power law relationships for both MTT and silica with discharge. Streamwater MTTs vary from 1 to 11 years. The results indicate that (1) relatively old waters dominate many streams, (2) streamwater ages vary with discharge, and (3) age, like silica, varies according to

  11. Glycosaminoglycans in the Human Cornea: Age-Related Changes

    PubMed Central

    Pacella, Elena; Pacella, Fernanda; De Paolis, Giulio; Parisella, Francesca Romana; Turchetti, Paolo; Anello, Giulia; Cavallotti, Carlo

    2015-01-01

    AIM To investigate possible age-related changes in glycosaminoglycans (GAGs) in the human cornea. The substances today called GAGs were previously referred to as mucopolysaccharides. METHODS Samples of human cornea were taken from 12 younger (age 21 ± 1.2) and 12 older (age 72 ± 1.6) male subjects. Samples were weighed, homogenized, and used for biochemical and molecular analyses. All the quantitative results were statistically analyzed. RESULTS The human cornea appears to undergo age-related changes, as evidenced by our biochemical and molecular results. The total GAG and hyaluronic acid counts were significantly higher in the younger subjects than in the older subjects. The sulfated heavy GAGs, such as chondroitin, dermatan, keratan, and heparan sulfate, were lower in the younger subjects than in the older subjects. DISCUSSION GAGs of the human cornea undergo numerous age-related changes. Their quantity is significantly altered in the elderly in comparison with younger subjects. GAGs play an important role in age-related diseases of the human cornea. PMID:25674020

  12. Awareness, Knowledge, and Concern about Age-Related Macular Degeneration

    ERIC Educational Resources Information Center

    Cimarolli, Verena R.; Laban-Baker, Allie; Hamilton, Wanda S.; Stuen, Cynthia

    2012-01-01

    Age-related macular degeneration (AMD)--a common eye disease causing vision loss--can be detected early through regular eye-health examinations, and measures can be taken to prevent visual decline. Getting eye examinations requires certain levels of awareness, knowledge, and concern related to AMD. However, little is known about AMD-related…

  13. Basin-Specific Variations in the Thermal Aging of Oceanic Asthenosphere

    NASA Astrophysics Data System (ADS)

    Paulson, E.; Jordan, T. H.

    2014-12-01

    To investigate the depth extent of mantle thermal aging beneath ocean basins, we project 3D Voigt averaged S-velocity variations from an ensemble of global tomographic models onto a 1º x 1º degree age-based regionalization and average each major ocean basin (Pacific, Atlantic, and Indian) in equal increments of the square-root of crustal age. By comparing the age averaged S-wave profiles, we estimate convergence depths, the minimum depths where age variations become statistically insignificant. Following Jordan & Paulson (JGR, doi:10.1002/jgrb.50263, 2013), we estimate aleatory variability in the S-wave profiles, correct for vertical smearing bias, and estimate epistemic uncertainties over the model ensemble. We can assert with 90% confidence that the age-correlated variations in Voigt-averaged S velocities persist to depths greater than 170 km. Given the strong evidence that the G discontinuity (~70 km) approximates the lithosphere-asthenosphere boundary (LAB) beneath ocean basins, we conclude that the upper part of the oceanic asthenosphere participates in the cooling that forms the kinematic plates. Age-averaged profiles show significant differences among the ocean basins. To quantify this, we fit age-dependent vertical travel times through the uppermost mantle of the models with an idealized Earth model having a strict square-root of age velocity structure in the ocean basins, suitably filtered to mimic tomographic smoothing. Good fits can be obtained for the Atlantic and Indian ocean basins out to 170 My, although the travel-time slopes for the former are steeper than the latter, implying more rapid cooling in the Atlantic. The Pacific basin shows significant deviations from simple conductive cooling for ages greater than about 50 My, in general agreement with previously published surface-wave models, indicating perturbations associated with small-scale convective processes. We conclude that large-scale flow advects small-scale heterogeneities due to

  14. Aging on a different scale – chronological versus pathology-related aging

    PubMed Central

    Melis, Joost P.M.; Jonker, Martijs J.; Vijg, Jan; Hoeijmakers, Jan H.J.; Breit, Timo M.; van Steeg, Harry

    2013-01-01

    In the next decades the elderly population will increase dramatically, demanding appropriate solutions in health care and aging research focusing on healthy aging to prevent high burdens and costs in health care. For this, research targeting tissue-specific and individual aging is paramount to make the necessary progression in aging research. In a recently published study we have attempted to make a step interpreting aging data on chronological as well as pathological scale. For this, we sampled five major tissues at regular time intervals during the entire C57BL/6J murine lifespan from a controlled in vivo aging study, measured the whole transcriptome and incorporated temporal as well as physical health aspects into the analyses. In total, we used 18 different age-related pathological parameters and transcriptomic profiles of liver, kidney, spleen, lung and brain and created a database that can now be used for a broad systems biology approach. In our study, we focused on the dynamics of biological processes during chronological aging and the comparison between chronological and pathology-related aging. PMID:24131799

  15. Discover the network mechanisms underlying the connections between aging and age-related diseases

    PubMed Central

    Yang, Jialiang; Huang, Tao; Song, Won-min; Petralia, Francesca; Mobbs, Charles V.; Zhang, Bin; Zhao, Yong; Schadt, Eric E.; Zhu, Jun; Tu, Zhidong

    2016-01-01

    Although our knowledge of aging has greatly expanded in the past decades, it remains elusive why and how aging contributes to the development of age-related diseases (ARDs). In particular, a global mechanistic understanding of the connections between aging and ARDs is yet to be established. We rely on a network modelling named “GeroNet” to study the connections between aging and more than a hundred diseases. By evaluating topological connections between aging genes and disease genes in over three thousand subnetworks corresponding to various biological processes, we show that aging has stronger connections with ARD genes compared to non-ARD genes in subnetworks corresponding to “response to decreased oxygen levels”, “insulin signalling pathway”, “cell cycle”, etc. Based on subnetwork connectivity, we can correctly “predict” if a disease is age-related and prioritize the biological processes that are involved in connecting to multiple ARDs. Using Alzheimer’s disease (AD) as an example, GeroNet identifies meaningful genes that may play key roles in connecting aging and ARDs. The top modules identified by GeroNet in AD significantly overlap with modules identified from a large scale AD brain gene expression experiment, supporting that GeroNet indeed reveals the underlying biological processes involved in the disease. PMID:27582315

  16. Discover the network mechanisms underlying the connections between aging and age-related diseases.

    PubMed

    Yang, Jialiang; Huang, Tao; Song, Won-Min; Petralia, Francesca; Mobbs, Charles V; Zhang, Bin; Zhao, Yong; Schadt, Eric E; Zhu, Jun; Tu, Zhidong

    2016-01-01

    Although our knowledge of aging has greatly expanded in the past decades, it remains elusive why and how aging contributes to the development of age-related diseases (ARDs). In particular, a global mechanistic understanding of the connections between aging and ARDs is yet to be established. We rely on a network modelling named "GeroNet" to study the connections between aging and more than a hundred diseases. By evaluating topological connections between aging genes and disease genes in over three thousand subnetworks corresponding to various biological processes, we show that aging has stronger connections with ARD genes compared to non-ARD genes in subnetworks corresponding to "response to decreased oxygen levels", "insulin signalling pathway", "cell cycle", etc. Based on subnetwork connectivity, we can correctly "predict" if a disease is age-related and prioritize the biological processes that are involved in connecting to multiple ARDs. Using Alzheimer's disease (AD) as an example, GeroNet identifies meaningful genes that may play key roles in connecting aging and ARDs. The top modules identified by GeroNet in AD significantly overlap with modules identified from a large scale AD brain gene expression experiment, supporting that GeroNet indeed reveals the underlying biological processes involved in the disease. PMID:27582315

  17. A "concrete view" of aging: event related potentials reveal age-related changes in basic integrative processes in language.

    PubMed

    Huang, Hsu-Wen; Meyer, Aaron M; Federmeier, Kara D

    2012-01-01

    Normal aging is accompanied by changes in both structural and functional cerebral organization. Although verbal knowledge seems to be relatively stable across the lifespan, there are age-related changes in the rapid use of that knowledge during on-line language processing. In particular, aging has been linked to reduce effectiveness in preparing for upcoming words and building an integrated sentence-level representation. The current study assessed whether such age-related changes extend even to much simpler language units, such as modification relations between a centrally presented adjective and a lateralized noun. Adjectives were used to elicit concrete and abstract meanings of the same, polysemous lexical items (e.g., "green book" vs. "interesting book"). Consistent with findings that lexical information is preserved with age, older adults, like younger adults, exhibited concreteness effects at the adjectives, with more negative responses to concrete adjectives over posterior (300-500 ms; N400) and frontal (300-900 ms) channels. However, at the noun, younger adults exhibited concreteness-based predictability effects linked to left hemisphere processing and imagery effects linked to right hemisphere processing, contingent on whether the adjectives and nouns formed a cohesive conceptual unit. In contrast, older adults showed neither effect, suggesting that they were less able to rapidly link the adjective-noun meaning to form an integrated conceptual representation. Age-related changes in language processing may thus be more pervasive than previously realized. PMID:22044648

  18. 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...

  19. Paleomagnetic secular variation and environmental magnetism of Holocene-age sediments from Tulare Lake, CA

    NASA Astrophysics Data System (ADS)

    Roza, Janine; Jackson, Brandon; Heaton, Eric; Negrini, Rob

    2016-05-01

    The lake-level record from Tulare Lake, CA has been shown to provide valuable constraints on late Pleistocene and Holocene runoff from the Sierra Nevada mountain range into the San Joaquin Valley of California, one of the world's most prolific agricultural centers. This project uses the magnetic properties of the Tulare Lake sediments in order to date the sediments and to constrain the relative lake level at the time of deposition. Shallowing lake conditions were identified leading up to a prominent unconformity; magnetic mineralogy and grain size indicators, primarily decreasing ARM/IRM and S-Ratio values suggest coarser grain sizes and more oxidizing conditions. Approximately half of the samples possessed well-behaved paleomagnetic directions suitable for paleomagnetic secular variation dating. The results indicate that the sediments below the unconformity were deposited approximately 7600-8500 cal yr BP, and the sediments above the unconformity were deposited approximately 2500-800 cal yr BP. The ages of the corresponding sediments are consistent with the time intervals during which previous studies indicate that lake level was above the elevation of this site, before and after a mid Holocene regression.

  20. Paleomagnetic Secular Variation and Environmental Magnetism of Holocene-aged Sediments from Tulare Lake, CA

    NASA Astrophysics Data System (ADS)

    Roza, J.; Jackson, B.; Heaton, E.; Negrini, R. M.

    2015-12-01

    The lake-level record from Tulare Lake, CA has been shown to provide valuable constraints on late Pleistocene and Holocene channelized runoff from the Sierra Nevada mountain range into the San Joaquin Valley of California, one of the world's most prolific agricultural centers. This project focuses on the use of magnetic properties of the Tulare Lake sediments in order to test previous results by dating the sediments and determining the relative lake level at the time of deposition. Shallowing lake conditions were identified leading up to a prominent unconformity from magnetic mineralogy and grain size indicators, primarily decreasing ARM/IRM and S-Ratio values suggesting coarser grain sizes and more oxidizing conditions. Approximately half of the samples possessed well-behaved paleomagnetic directions suitable for paleomagnetic secular variation dating. The results indicate that the sediments below the unconformity were deposited approximately 7600-6700 14C years ago (~7600 to 8500 cal yr B.P.), and the sediments above the unconformity were deposited approximately 2200-500 14C years ago. The ages of the corresponding sediments are consistent with the time intervals during which lake level was predicted to be above the elevation of the Poso Canal site before and after a mid-Holocene regression.

  1. Relational learning and transitive expression in aging and amnesia.

    PubMed

    Ryan, Jennifer D; D'Angelo, Maria C; Kamino, Daphne; Ostreicher, Melanie; Moses, Sandra N; Rosenbaum, R Shayna

    2016-02-01

    Aging has been associated with a decline in relational memory, which is critically supported by the hippocampus. By adapting the transitivity paradigm (Bunsey and Eichenbaum (1996) Nature 379:255-257), which traditionally has been used in nonhuman animal research, this work examined the extent to which aging is accompanied by deficits in relational learning and flexible expression of relational information. Older adults' performance was additionally contrasted with that of amnesic case DA to understand the critical contributions of the medial temporal lobe, and specifically, the hippocampus, which endures structural and functional changes in healthy aging. Participants were required to select the correct choice item (B versus Y) based on the presented sample item (e.g., A). Pairwise relations must be learned (A->B, B->C, C->D) so that ultimately, the correct relations can be inferred when presented with a novel probe item (A->C?Z?). Participants completed four conditions of transitivity that varied in terms of the degree to which the stimuli and the relations among them were known pre-experimentally. Younger adults, older adults, and DA performed similarly when the condition employed all pre-experimentally known, semantic, relations. Older adults and DA were less accurate than younger adults when all to-be-learned relations were arbitrary. However, accuracy improved for older adults when they could use pre-experimentally known pairwise relations to express understanding of arbitrary relations as indexed through inference judgments. DA could not learn arbitrary relations nor use existing knowledge to support novel inferences. These results suggest that while aging has often been associated with an emerging decline in hippocampal function, prior knowledge can be used to support novel inferences. However, in case DA, significant damage to the hippocampus likely impaired his ability to learn novel relations, while additional damage to ventromedial prefrontal and

  2. The neural architecture of age-related dual-task interferences

    PubMed Central

    Chmielewski, Witold X.; Yildiz, Ali; Beste, Christian

    2014-01-01

    In daily life elderly adults exhibit deficits when dual-tasking is involved. So far these deficits have been verified on a behavioral level in dual-tasking. Yet, the neuronal architecture of these deficits in aging still remains to be explored especially when late-middle aged individuals around 60 years of age are concerned. Neuroimaging studies in young participants concerning dual-tasking were, among others, related to activity in middle frontal (MFG) and superior frontal gyrus (SFG) and the anterior insula (AI). According to the frontal lobe hypothesis of aging, alterations in these frontal regions (i.e., SFG and MFG) might be responsible for cognitive deficits. We measured brain activity using fMRI, while examining age-dependent variations in dual-tasking by utilizing the PRP (psychological refractory period) test. Behavioral data showed an increasing PRP effect in late-middle aged adults. The results suggest the age-related deteriorated performance in dual-tasking, especially in conditions of risen complexity. These effects are related to changes in networks involving the AI, the SFG and the MFG. The results suggest that different cognitive subprocesses are affected that mediate the observed dual-tasking problems in late-middle aged individuals. PMID:25132818

  3. Towards age/rotation/magnetic activity relation with seismology

    NASA Astrophysics Data System (ADS)

    Mathur, Savita

    2015-09-01

    The knowledge of stellar ages directly impacts the characterization of a planetary system as it puts strong constraints on the moment when the system was born. Unfortunately, the determination of precise stellar ages is a very difficult task. Different methods can be used to do so (based on isochrones or chemical element abundances) but they usually provide large uncertainties. During its evolution a star goes through processes leading to loss of angular momentum but also changes in its magnetic activity. Building rotation, magnetic, age relations would be an asset to infer stellar ages model independently. Several attempts to build empirical relations between rotation and age (namely gyrochronology) were made with a focus on cluster stars where the age determination is easier and for young stars on the main sequence. For field stars, we can now take advantage of high-precision photometric observations where we can perform asteroseismic analyses to improve the accuracy of stellar ages. Furthermore, the variability in the light curves allow us to put strong constraints on the stellar rotation and magnetic activity. By combining these precise measurements, we are on the way of understanding and improving relations between magnetic activity, rotation, and age, in particular at different stages of stellar evolution. I will review the status on gyrochronology relationships based on observations of young cluster stars. Then I will focus on solar-like stars and describe the inferences on stellar ages, rotation, and magnetism that can be provided by high-quality photometric observations such as the ones of the Kepler mission, in particular through asteroseismic analyses.

  4. The Prevalence of Age-Related Eye Diseases and Visual Impairment in Aging: Current Estimates

    PubMed Central

    Klein, Ronald; Klein, Barbara E. K.

    2013-01-01

    Purpose. To examine prevalence of five age-related eye conditions (age-related cataract, AMD, open-angle glaucoma, diabetic retinopathy [DR], and visual impairment) in the United States. Methods. Review of published scientific articles and unpublished research findings. Results. Cataract, AMD, open-angle glaucoma, DR, and visual impairment prevalences are high in four different studies of these conditions, especially in people over 75 years of age. There are disparities among racial/ethnic groups with higher age-specific prevalence of DR, open-angle glaucoma, and visual impairment in Hispanics and blacks compared with whites, higher prevalence of age-related cataract in whites compared with blacks, and higher prevalence of late AMD in whites compared with Hispanics and blacks. The estimates are based on old data and do not reflect recent changes in the distribution of age and race/ethnicity in the United States population. There are no epidemiologic estimates of prevalence for many visually-impairing conditions. Conclusions. Ongoing prevalence surveys designed to provide reliable estimates of visual impairment, AMD, age-related cataract, open-angle glaucoma, and DR are needed. It is important to collect objective data on these and other conditions that affect vision and quality of life in order to plan for health care needs and identify areas for further research. PMID:24335069

  5. Conceptual Structure and Semantic Variation for Spatial Relations

    ERIC Educational Resources Information Center

    Khetarpal, Naveen Mohan

    2012-01-01

    Semantic categories across languages appear to reflect both universal conceptual tendencies and linguistic convention. To accommodate this pattern of constrained variation, many theories assume the existence of a universal conceptual space and explain cross-language variation in category extension as language-specific partitions of that space.…

  6. Age-Related and Sex-Related Differences in Hand and Pinch Grip Strength in Adults

    ERIC Educational Resources Information Center

    Puh, Urska

    2010-01-01

    The purpose of the study was to quantify age-related changes in hand grip strength and three types of pinch grip strength (key pinch, tip pinch, and palmar pinch) among male and female participants. The study included 199 healthy participants (100 females, 99 males) aged 20-79 years, who were divided into four age groups. The Baseline Hydraulic…

  7. Variation Principles and Applications in the Study of Cell Structure and Aging

    NASA Technical Reports Server (NTRS)

    Economos, Angelos C.; Miquel, Jaime; Ballard, Ralph C.; Johnson, John E., Jr.

    1981-01-01

    In this report we have attempted to show that "some reality lies concealed in biological variation". This "reality" has its principles, laws, mechanisms, and rules, only a few of which we have sketched. A related idea we pursued was that important information may be lost in the process of ignoring frequency distributions of physiological variables (as is customary in experimental physiology and gerontology). We suggested that it may be advantageous to expand one's "statistical field of vision" beyond simple averages +/- standard deviations. Indeed, frequency distribution analysis may make visible some hidden information not evident from a simple qualitative analysis, particularly when the effect of some external factor or condition (e.g., aging, dietary chemicals) is being investigated. This was clearly illustrated by the application of distribution analysis in the study of variation in mouse liver cellular and fine structure, and may be true of fine structural studies in general. In living systems, structure and function interact in a dynamic way; they are "inseparable," unlike in technological systems or machines. Changes in fine structure therefore reflect changes in function. If such changes do not exceed a certain physiologic range, a quantitative analysis of structure will provide valuable information on quantitative changes in function that may not be possible or easy to measure directly. Because there is a large inherent variation in fine structure of cells in a given organ of an individual and among individuals, changes in fine structure can be analyzed only by studying frequency distribution curves of various structural characteristics (dimensions). Simple averages +/- S.D. do not in general reveal all information on the effect of a certain factor, because often this effect is not uniform; on the contrary, this will be apparent from distribution analysis because the form of the curves will be affected. We have also attempted to show in this chapter that

  8. Relative age-related participation and dropout trends in German youth sports clubs.

    PubMed

    Wattie, Nick; Tietjens, Maike; Cobley, Stephen; Schorer, Jörg; Baker, Joseph; Kurz, Dietrich

    2014-01-01

    Relative age describes a youth's age within their age group cohort. Compared to relatively younger peers, relatively older youth in an annual age group cohort have been found more likely to be selected to sports teams, and to receive higher grades in education. This study examined the influence of youth sport participants' relative age on participation and dropout. Using data from the 1995 German Youth Sport Survey (N total=2612), comparisons (stratified by gender and sport type) were made between the relative age of current and former participants. Analyses also considered the type of school youths were enrolled in while exploring the influence of relative age on sport participations. No relative age effects for dropout emerged among males in team or individual sport contexts. Female dropouts were more likely to be relatively older (Q1, OR adjusted: 0.52, 95% CI: 0.34-0.80; Q2, OR adjusted: 0.55, 95% CI: 0.36-0.84; Q3, OR adjusted: 0.59, 95% CI: 0.39-0.89), an effect that was mirrored among 'artistic' sport participants. Boys and girls in schools that were for children of higher academic proficiency were more likely to be currently participating in sport. Findings suggest that relative age-related dropout effects may be context sensitive and different for males and females. For the most part, relative age did not appear to have any relationship with dropout in this sample, with some notable exceptions for females. Overall, factors such as the type of school youths were enrolled in appear to be a more salient influence on sport participation than relative age. PMID:24444209

  9. 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

  10. 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

  11. Parainflammation, chronic inflammation and age-related macular degeneration

    PubMed Central

    Chen, Mei; Xu, Heping

    2016-01-01

    Inflammation is an adaptive response of the immune system to noxious insults to maintain homeostasis and restore functionality. The retina is considered an immune privileged tissue due to its unique anatomical and physiological properties. During aging, the retina suffers from a low-grade chronic oxidative insult, which sustains for decades and increases in level with advancing age. As a result, the retinal innate immune system, particularly microglia and the complement system, undergo low levels of activation (para-inflammation). In many cases, this para-inflammatory response can maintain homeostasis in the healthy aging eye. However, in patients with age-related macular degeneration (AMD), this para-inflammatory response becomes dysregulated and contributes to macular damage. Factors contributing to the dysregulation of age-related retinal para-inflammation include genetic predisposition, environmental risk factors and old age. Dysregulated para-inflammation (chronic inflammation) in AMD damages the blood retina barrier (BRB), resulting in the breach of retinal immune privilege leading to the development of retinal lesions. This review discusses the basic principles of retinal innate immune responses to endogenous chronic insults in normal aging and in AMD, and explores the difference between beneficial para-inflammation and the detrimental chronic inflammation in the context of AMD. PMID:26292978

  12. The effects of gender and age on health related behaviors

    PubMed Central

    Deeks, Amanda; Lombard, Catherine; Michelmore, Janet; Teede, Helena

    2009-01-01

    Background Lifestyle-related diseases, including diabetes, cardiovascular disease, and some cancers represent the greatest global health threat. Greater insight into health needs and beliefs, using broad community samples, is vital to reduce the burden of chronic disease. This study aimed to investigate gender, age, screening practices, health beliefs, and perceived future health needs for healthy ageing. Methods Random probability sampling using self-completion surveys in 1456 adults residing in Australia. Results Screening behaviors were associated with gender and age. Men and women >51 years were more likely (27%) to have screening health checks than those <50 years (2%). Factors nominated to influence health were lifestyle (92%), relationships (82%), and environment (80%). Women were more likely to nominate preparedness to have an annual health check, willingness to seek advice from their medical practitioner and to attend education sessions. Numerous health fears were associated with ageing, however participants were more likely to have a financial (72%) rather than a health plan (42%). More women and participants >51 years wanted information regarding illness prevention than men or those aged <30 years. Conclusion Age and gender are associated with health related behaviors. Optimal health is perceived as a priority, yet often this perception is not translated into preventative action. These findings will inform future research and policy makers as we strive towards a healthier ageing society and the prevention of chronic disease. PMID:19563685

  13. Sources of tooth wear variation early in life among known-aged wild ring-tailed lemurs (Lemur catta) at the Bezà Mahafaly Special Reserve, Madagascar.

    PubMed

    Cuozzo, Frank P; Head, Brian R; Sauther, Michelle L; Ungar, Peter S; O'Mara, M Teague

    2014-11-01

    Ring-tailed lemurs (Lemur catta) at the Bezà Mahafaly Special Reserve (BMSR), Madagascar display a high frequency of individuals with notable and sometimes extreme tooth wear. Adult lemurs display a range of tooth wear even among individuals of the same age, but we do not know at what age this variation first appears. This study's goal was to determine whether wear variation occurs in younger wild lemurs. Based on the decade-long study of ring-tailed lemur feeding and dental ecology at BMSR, we hypothesized that younger, natal lemurs (under 5 years of age), would display variation in their degree of tooth wear that would correspond to microhabitat differences, given differences in food availability in different troops' home ranges. We also hypothesized that wear would differ between sexes at this young age, given differences in feeding between males and females in this population. Hypotheses were tested using dental topographic analyses using dental impressions collected from known-aged lemurs across 10 years at BMSR. Results illustrate significant differences in wear-related tooth topography (i.e., relief and slope, presented here as "occlusal lift") for microhabitat, sex and troop affiliation among lemurs under 5 years of age in this population. Although, all lemurs in this population consume mechanically challenging tamarind fruit, those in more disturbed habitats eat additional introduced foods, some of which are also mechanically challenging. Thus, dietary variation is the likely cause of variation in tooth wear. The wear variation we show at a young age suggests caution when assigning age based on tooth wear in living and fossil primates. These wear-related tooth shape changes early in life, which reflects sex, habitat variation and levels of anthropogenic disturbance, may potentially impact reproductive fitness later in life. PMID:24953664

  14. Age-related mutations and chronic myelomonocytic leukemia.

    PubMed

    Mason, C C; Khorashad, J S; Tantravahi, S K; Kelley, T W; Zabriskie, M S; Yan, D; Pomicter, A D; Reynolds, K R; Eiring, A M; Kronenberg, Z; Sherman, R L; Tyner, J W; Dalley, B K; Dao, K-H; Yandell, M; Druker, B J; Gotlib, J; O'Hare, T; Deininger, M W

    2016-04-01

    Chronic myelomonocytic leukemia (CMML) is a hematologic malignancy nearly confined to the elderly. Previous studies to determine incidence and prognostic significance of somatic mutations in CMML have relied on candidate gene sequencing, although an unbiased mutational search has not been conducted. As many of the genes commonly mutated in CMML were recently associated with age-related clonal hematopoiesis (ARCH) and aged hematopoiesis is characterized by a myelomonocytic differentiation bias, we hypothesized that CMML and aged hematopoiesis may be closely related. We initially established the somatic mutation landscape of CMML by whole exome sequencing followed by gene-targeted validation. Genes mutated in ⩾10% of patients were SRSF2, TET2, ASXL1, RUNX1, SETBP1, KRAS, EZH2, CBL and NRAS, as well as the novel CMML genes FAT4, ARIH1, DNAH2 and CSMD1. Most CMML patients (71%) had mutations in ⩾2 ARCH genes and 52% had ⩾7 mutations overall. Higher mutation burden was associated with shorter survival. Age-adjusted population incidence and reported ARCH mutation rates are consistent with a model in which clinical CMML ensues when a sufficient number of stochastically acquired age-related mutations has accumulated, suggesting that CMML represents the leukemic conversion of the myelomonocytic-lineage-biased aged hematopoietic system. PMID:26648538

  15. Age-related differences in working memory updating components.

    PubMed

    Linares, Rocío; Bajo, M Teresa; Pelegrina, Santiago

    2016-07-01

    The aim of this study was to investigate possible age-related changes throughout childhood and adolescence in different component processes of working memory updating (WMU): retrieval, transformation, and substitution. A set of numerical WMU tasks was administered to four age groups (8-, 11-, 14-, and 21-year-olds). To isolate the effect of each of the WMU components, participants performed different versions of a task that included different combinations of the WMU components. The results showed an expected overall decrease in response times and an increase in accuracy performance with age. Most important, specific age-related changes in the retrieval component were found, demonstrating that the effect of retrieval on accuracy was larger in children than in adolescents or young adults. These findings indicate that the availability of representations from outside the focus of attention may change with age. Thus, the retrieval component of updating could contribute to the age-related changes observed in the performance of many updating tasks. PMID:26985577

  16. Age-Related Changes in Electroencephalographic Signal Complexity

    PubMed Central

    Zappasodi, Filippo; Marzetti, Laura; Olejarczyk, Elzbieta; Tecchio, Franca; Pizzella, Vittorio

    2015-01-01

    The study of active and healthy aging is a primary focus for social and neuroscientific communities. Here, we move a step forward in assessing electrophysiological neuronal activity changes in the brain with healthy aging. To this end, electroencephalographic (EEG) resting state activity was acquired in 40 healthy subjects (age 16–85). We evaluated Fractal Dimension (FD) according to the Higuchi algorithm, a measure which quantifies the presence of statistical similarity at different scales in temporal fluctuations of EEG signals. Our results showed that FD increases from age twenty to age fifty and then decreases. The curve that best fits the changes in FD values across age over the whole sample is a parabola, with the vertex located around age fifty. Moreover, FD changes are site specific, with interhemispheric FD asymmetry being pronounced in elderly individuals in the frontal and central regions. The present results indicate that fractal dimension well describes the modulations of brain activity with age. Since fractal dimension has been proposed to be related to the complexity of the signal dynamics, our data demonstrate that the complexity of neuronal electric activity changes across the life span of an individual, with a steady increase during young adulthood and a decrease in the elderly population. PMID:26536036

  17. Variation in osteon histomorphometrics and their impact on age-at-death estimation in older individuals.

    PubMed

    Goliath, Jesse R; Stewart, Marissa C; Stout, Sam D

    2016-05-01

    Histomorphometric studies have reported relations between osteon size and age; however, data focused on the shape of osteons is sparse. The purpose of this study was to determine how osteon circularity (On.Cr) varies with age in different skeletal elements. Regression analysis was used to evaluate the relationship between age and osteon shape and size. We hypothesized that age would be negatively related to osteon size (area, On.Ar) and positively related to osteon shape (On.Cr). On.Cr and On.Ar were determined for the ribs and femora of 27 cadaveric specimens with known age-at-death. As predicted, age was significantly related to osteon size and shape for both the femur and rib. With age, there was a decrease in size and an increase in circularity. No relationship between sex and On.Cr was detected. An age predicting model, including On.Cr, On.Ar and OPD, is proposed to improve our ability to estimate age-at-death, especially for older individuals. PMID:27021159

  18. Age-related declines in immune response in a wild mammal are unrelated to immune cell telomere length.

    PubMed

    Beirne, Christopher; Waring, Laura; McDonald, Robbie A; Delahay, Richard; Young, Andrew

    2016-02-24

    Senescence has been hypothesized to arise in part from age-related declines in immune performance, but the patterns and drivers of within-individual age-related changes in immunity remain virtually unexplored in natural populations. Here, using a long-term epidemiological study of wild European badgers (Meles meles), we (i) present evidence of a within-individual age-related decline in the response of a key immune-signalling cytokine, interferon-gamma (IFNγ), to ex vivo lymphocyte stimulation, and (ii) investigate three putative drivers of individual variation in the rate of this decline (sex, disease and immune cell telomere length; ICTL). That the within-individual rate of age-related decline markedly exceeded that at the population level suggests that individuals with weaker IFNγ responses are selectively lost from this population. IFNγ responses appeared to decrease with the progression of bovine tuberculosis infection (independent of age) and were weaker among males than females. However, neither sex nor disease influenced the rate of age-related decline in IFNγ response. Similarly, while ICTL also declines with age, variation in ICTL predicted neither among- nor within-individual variation in IFNγ response. Our findings provide evidence of within-individual age-related declines in immune performance in a wild mammal and highlight the likely complexity of the mechanisms that generate them. PMID:26888036

  19. Age-related declines in immune response in a wild mammal are unrelated to immune cell telomere length

    PubMed Central

    Waring, Laura; McDonald, Robbie A.; Delahay, Richard; Young, Andrew

    2016-01-01

    Senescence has been hypothesized to arise in part from age-related declines in immune performance, but the patterns and drivers of within-individual age-related changes in immunity remain virtually unexplored in natural populations. Here, using a long-term epidemiological study of wild European badgers (Meles meles), we (i) present evidence of a within-individual age-related decline in the response of a key immune-signalling cytokine, interferon-gamma (IFNγ), to ex vivo lymphocyte stimulation, and (ii) investigate three putative drivers of individual variation in the rate of this decline (sex, disease and immune cell telomere length; ICTL). That the within-individual rate of age-related decline markedly exceeded that at the population level suggests that individuals with weaker IFNγ responses are selectively lost from this population. IFNγ responses appeared to decrease with the progression of bovine tuberculosis infection (independent of age) and were weaker among males than females. However, neither sex nor disease influenced the rate of age-related decline in IFNγ response. Similarly, while ICTL also declines with age, variation in ICTL predicted neither among- nor within-individual variation in IFNγ response. Our findings provide evidence of within-individual age-related declines in immune performance in a wild mammal and highlight the likely complexity of the mechanisms that generate them. PMID:26888036

  20. 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

  1. ROS, Cell Senescence, and Novel Molecular Mechanisms in Aging and Age-Related Diseases

    PubMed Central

    Davalli, Pierpaola; Mitic, Tijana; Caporali, Andrea; Lauriola, Angela; D'Arca, Domenico

    2016-01-01

    The aging process worsens the human body functions at multiple levels, thus causing its gradual decrease to resist stress, damage, and disease. Besides changes in gene expression and metabolic control, the aging rate has been associated with the production of high levels of Reactive Oxygen Species (ROS) and/or Reactive Nitrosative Species (RNS). Specific increases of ROS level have been demonstrated as potentially critical for induction and maintenance of cell senescence process. Causal connection between ROS, aging, age-related pathologies, and cell senescence is studied intensely. Senescent cells have been proposed as a target for interventions to delay the aging and its related diseases or to improve the diseases treatment. Therapeutic interventions towards senescent cells might allow restoring the health and curing the diseases that share basal processes, rather than curing each disease in separate and symptomatic way. Here, we review observations on ROS ability of inducing cell senescence through novel mechanisms that underpin aging processes. Particular emphasis is addressed to the novel mechanisms of ROS involvement in epigenetic regulation of cell senescence and aging, with the aim to individuate specific pathways, which might promote healthy lifespan and improve aging. PMID:27247702

  2. Physiological Antioxidative Network of the Bilirubin System in Aging and Age-Related Diseases

    PubMed Central

    Kim, Sung Young; Park, Sang Chul

    2012-01-01

    Oxidative stress is detrimental to life process and is particularly responsible for aging and age-related diseases. Thus, most organisms are well equipped with a spectrum of biological defense mechanisms against oxidative stress. The major efficient antioxidative mechanism is the glutathione system, operating a redox cycling mechanism for glutathione utilization, which consists of glutathione and its peroxidase and reductase. However, this system is mainly effective for hydrophilic oxidants, while lipophilic oxidants require another scavenging system. Since many age-related pathological conditions are related to lipid peroxidation, especially in association with the aging process, the physiological role of the scavenging system for lipophilic oxidants should be considered. In this regard, the biliverdin to bilirubin conversion pathway, via biliverdin reductase (BVR), is suggested to be another major protective mechanism that scavenges lipophilic oxidants because of the lipophilic nature of bilirubin. The efficiency of this bilirubin system might be potentiated by operation of the intertwined bicyclic systems of the suggested redox metabolic cycle of biliverdin and bilirubin and the interactive control cycle of BVR and heme oxygenase. In order to combat oxidative stress, both antioxidative systems against hydrophilic and lipophilic oxidants are required to work cooperatively. In this regard, the roles of the bilirubin system in aging and age-related diseases are reassessed in this review, and their interacting networks are evaluated. PMID:22457648

  3. [Decline in renal function in old age : Part of physiological aging versus age-related disease].

    PubMed

    Braun, F; Brinkkötter, P T

    2016-08-01

    The incidence and prevalence of chronic renal disease (CKD) in elderly patients are continuously increasing worldwide. Loss of renal function is not only considered to be part of the aging process itself but also reflects the multimorbidity of many geriatric patients. Calculating the glomerular filtration rate using specific algorithms validated for the elderly population and measuring the amount of proteinuria allow an estimation of renal function in elderly patients with high accuracy. Chronic renal failure has many clinical consequences and not only results in a delayed excretion of toxins cleared by the kidneys but also affects hematogenesis, water and electrolyte balance as well as mineral bone metabolism. Furthermore, CKD directly leads to and aggravates geriatric syndromes and in particular the onset of frailty. Therapeutic strategies to halt progression of CKD not only comprise treatment of the underlying disease but also efficient blood pressure and diabetic control and the avoidance of nephrotoxic medications. PMID:27457360

  4. Oxidative stress and age-related neuronal deficits.

    PubMed

    Joseph, J A; Denisova, N; Villalobos-Molina, R; Erat, S; Strain, J

    1996-01-01

    Research from our laboratory has indicated that the loss of sensitivity that occurs in several receptor systems as a function of age may be an index of an increasing inability to respond to oxidative stress (OS). This loss occurs partially as a result of altered signal transduction (ST). Assessments have involved determining the nature of age-related reductions in oxotremorine enhancement of K(+)-evoked dopamine release (K(+)-ERDA) from superfused striatal slices. Using this model, we have found that 1. Reductions can be restored with in vivo administration of the free-radical trapping agent, N-tert-butyl-alpha-phenylnitrone (PBN); 2. Decrements in DA release induced by NO or H2O2 from striatal slices from both young and old animals could be restored with alpha-tocopherol or PBN; 3. ST decrements, such as those seen in aging, could be induced with radiation exposure; and 4. Pre-incubation of the striatal slices with cholesterol decreased subsequent deleterious effects of NO or OH. on DA release. Thus, cholesterol, which increases in neuronal membranes as a function of age, may function as a potent antioxidant and protectant against neuronal damage. These results suggest that therapeutic efforts to restore cognitive deficits in aging and age-related disease might begin with antioxidant reversal of ST decrements. PMID:8871939

  5. Dissecting simulated disc galaxies - II. The age-velocity relation

    NASA Astrophysics Data System (ADS)

    Martig, Marie; Minchev, Ivan; Flynn, Chris

    2014-09-01

    We study the relation between stellar ages and vertical velocity dispersion (the age-velocity relation, or AVR) in a sample of seven simulated disc galaxies. In our simulations, the shape of the AVR for stars younger than 9 Gyr depends strongly on the merger history at low redshift, with even 1:10-1:15 mergers being able to create jumps in the AVR (although these jumps might not be detectable if the errors on stellar ages are of the order of 30 per cent). For galaxies with a quiescent history at low redshift, we find that the vertical velocity dispersion rises smoothly for ages up to 8-9 Gyr, following a power law with a slope of ˜0.5, similar to what is observed in the solar neighbourhood by the Geneva-Copenhagen Survey. For these galaxies, we show that the slope of the AVR is not imprinted at birth, but is the result of subsequent heating. By contrast, in all our simulations, the oldest stars form a significantly different population, with a high velocity dispersion. These stars are usually born kinematically hot in a turbulent phase of intense mergers at high redshift, and also include some stars accreted from satellites. This maximum in σz is strongly decreased when age errors are included, suggesting that observations can easily miss such a jump with the current accuracy of age measurements.

  6. Age-related differences in moral identity across adulthood.

    PubMed

    Krettenauer, Tobias; Murua, Lourdes Andrea; Jia, Fanli

    2016-06-01

    In this study, age-related differences in adults' moral identity were investigated. Moral identity was conceptualized a context-dependent self-structure that becomes differentiated and (re)integrated in the course of development and that involves a broad range of value-orientations. Based on a cross-sectional sample of 252 participants aged 14 to 65 years (148 women, M = 33.5 years, SD = 16.9) and a modification of the Good Self-Assessment, it was demonstrated that mean-level of moral identity (averaged across the contexts of family, school/work, and community) significantly increased in the adult years, whereas cross-context differentiation showed a nonlinear trend peaking at the age of 25 years. Value-orientations that define individuals' moral identity shifted so that self-direction and rule-conformity became more important with age. Age-related differences in moral identity were associated with, but not fully attributable to changes in personality traits. Overall, findings suggest that moral identity development is a lifelong process that starts in adolescence but expands well into middle age. (PsycINFO Database Record PMID:27124654

  7. Clade age and diversification rate variation explain disparity in species richness among water scavenger beetle (Hydrophilidae) lineages.

    PubMed

    Bloom, Devin D; Fikáček, Martin; Short, Andrew E Z

    2014-01-01

    Explaining the disparity of species richness across the tree of life is one of the great challenges in evolutionary biology. Some lineages are exceptionally species rich, while others are relatively species poor. One explanation for heterogeneity among clade richness is that older clades are more species rich because they have had more time to accrue diversity than younger clades. Alternatively, disparity in species richness may be due to among-lineage diversification rate variation. Here we investigate diversification in water scavenger beetles (Hydrophilidae), which vary in species richness among major lineages by as much as 20 fold. Using a time-calibrated phylogeny and comparative methods, we test for a relationship between clade age and species richness and for shifts in diversification rate in hydrophilids. We detected a single diversification rate increase in Megasternini, a relatively young and species rich clade whose diversity might be explained by the stunning diversity of ecological niches occupied by this clade. We find that Amphiopini, an old clade, is significantly more species poor than expected, possibly due to its restricted geographic range. The remaining lineages show a correlation between species richness and clade age, suggesting that both clade age and variation in diversification rates explain the disparity in species richness in hydrophilids. We find little evidence that transitions between aquatic, semiaquatic, and terrestrial habitats are linked to shifts in diversification rates. PMID:24887453

  8. Clade Age and Diversification Rate Variation Explain Disparity in Species Richness among Water Scavenger Beetle (Hydrophilidae) Lineages

    PubMed Central

    Bloom, Devin D.; Fikáček, Martin; Short, Andrew E. Z.

    2014-01-01

    Explaining the disparity of species richness across the tree of life is one of the great challenges in evolutionary biology. Some lineages are exceptionally species rich, while others are relatively species poor. One explanation for heterogeneity among clade richness is that older clades are more species rich because they have had more time to accrue diversity than younger clades. Alternatively, disparity in species richness may be due to among-lineage diversification rate variation. Here we investigate diversification in water scavenger beetles (Hydrophilidae), which vary in species richness among major lineages by as much as 20 fold. Using a time-calibrated phylogeny and comparative methods, we test for a relationship between clade age and species richness and for shifts in diversification rate in hydrophilids. We detected a single diversification rate increase in Megasternini, a relatively young and species rich clade whose diversity might be explained by the stunning diversity of ecological niches occupied by this clade. We find that Amphiopini, an old clade, is significantly more species poor than expected, possibly due to its restricted geographic range. The remaining lineages show a correlation between species richness and clade age, suggesting that both clade age and variation in diversification rates explain the disparity in species richness in hydrophilids. We find little evidence that transitions between aquatic, semiaquatic, and terrestrial habitats are linked to shifts in diversification rates. PMID:24887453

  9. Effect of NCAM on aged-related deterioration in vision.

    PubMed

    Luke, Margaret Po-Shan; LeVatte, Terry L; O'Reilly, Amanda M; Smith, Benjamin J; Tremblay, François; Brown, Richard E; Clarke, David B

    2016-05-01

    The neural cell adhesion molecule (NCAM) is involved in developmental processes and age-associated cognitive decline; however, little is known concerning the effects of NCAM in the visual system during aging. Using anatomical, electrophysiological, and behavioral assays, we analyzed age-related changes in visual function of NCAM deficient (-/-) and wild-type mice. Anatomical analyses indicated that aging NCAM -/- mice had fewer retinal ganglion cells, thinner retinas, and fewer photoreceptor cell layers than age-matched controls. Electroretinogram testing of retinal function in young adult NCAM -/- mice showed a 2-fold increase in a- and b-wave amplitude compared with wild-type mice, but the retinal activity dropped dramatically to control levels when the animals reached 10 months. In behavioral tasks, NCAM -/- mice had no visual pattern discrimination ability and showed premature loss of vision as they aged. Together, these findings demonstrate that NCAM plays significant roles in the adult visual system in establishing normal retinal anatomy, physiology and function, and in maintaining vision during aging. PMID:27103522

  10. Modulation of cell death in age-related diseases.

    PubMed

    Tezil, Tugsan; Basaga, Huveyda

    2014-01-01

    Aging is a stage of life of all living organisms. According to the free-radical theory, aging cells gradually become unable to maintain cellular homeostasis due to the adverse effects of reactive oxygen species (ROS). ROS can cause irreversible DNA mutations, protein and lipid damage which are increasingly accumulated in the course of time if cells could not overcome these effects by the antioxidant defence system. Accrued damaged molecules in cells may either induce cellular death or contribute to develop various pathologies. Hence, programmed cell death mechanisms, apoptosis and autophagy, play a vital role in the aging process. Although they are strictly controlled by various interconnected signalling pathways, alterations in their regulations may contribute to severe pathologies including cancer, Alzheimer's and Parkinson's diseases. In this review, we summarized our current understanding and hypotheses regarding oxidative stress and age-related dysregulation of cell death signalling pathways. PMID:24079770

  11. The Age Related Properties of Solar Type Stars

    NASA Technical Reports Server (NTRS)

    Soderblom, David

    1999-01-01

    The studies of lithium in solar-type stars in clusters of a wide range of ages has provided critical information on a tracer of convective processes, especially among very young stars. Our most recent work has been on a pre-main sequence cluster (NGC 2264) that took place after this grant expired, but was founded on it. The spread seen in Li in Zero-Age Main Sequence clusters like the Pleiades is huge and possibly related to rotation. No clear spread in seen in NGC 2264, so it does not have its origins in the conditions of formation but is instead a result of processes occurring during PMS evolution. Our observations of M67 were particularly interesting because this cluster is the same age as the Sun, i.e.,very old. Clear evidence was seen for a spread in Li there too, indicating that the spread seen in very young stars perpetuates itself into old age.

  12. Variation in the Markers of Nutritional and Oxidative State in a Long-Lived Seabird: Associations with Age and Longevity.

    PubMed

    Urvik, Janek; Meitern, Richard; Rattiste, Kalev; Saks, Lauri; Hõrak, Peeter; Sepp, Tuul

    2016-01-01

    Age-related declines in life-history traits have been widely observed in free-living animals. Several theories link senescence to oxidative stress. The aim of this study was to measure several widely used markers of oxidative and nutritional state in a long-lived seabird, the common gull (Larus canus), in order to assess the suitability of these markers for describing deterioration in physiological condition associated with chronological age and survival. Associations with longevity and individual consistency of these parameters over the years (repeatability) were also assessed. Senescence in fitness parameters was observed during the study period: in females, laying date and clutch mass were related to bird age in a curvilinear manner, with middle-aged birds breeding earlier and laying heavier eggs. The only parameter associated with aging processes was glutathione concentration in erythrocytes, which was lower in female birds with longer life spans. Of indexes of nutritional state, plasma triglyceride concentration showed a between-individual increase with age, suggesting selective mortality of birds with low levels. Additionally, total plasma protein levels of individual males increased with age. The mostly negative results of this study hint that the commonly used parameters of physiological condition and oxidative state used in this study do not adequately reflect an individual's long-term health condition. Alternatively, it is possible that in common gulls, senescence occurs in reproductive mechanisms but not in mechanisms responsible for maintaining an organism's redox balance, consistent with the idea that different aspects of an organism's physiological condition age at different rates. Significant interannual repeatability was detected in three plasma constituents-carotenoids, uric acid, and total protein-all of which can possibly be linked to variation in dietary habits. PMID:27617362

  13. Hhip haploinsufficiency sensitizes mice to age-related emphysema.

    PubMed

    Lao, Taotao; Jiang, Zhiqiang; Yun, Jeong; Qiu, Weiliang; Guo, Feng; Huang, Chunfang; Mancini, John Dominic; Gupta, Kushagra; Laucho-Contreras, Maria E; Naing, Zun Zar Chi; Zhang, Li; Perrella, Mark A; Owen, Caroline A; Silverman, Edwin K; Zhou, Xiaobo

    2016-08-01

    Genetic variants in Hedgehog interacting protein (HHIP) have consistently been associated with the susceptibility to develop chronic obstructive pulmonary disease and pulmonary function levels, including the forced expiratory volume in 1 s (FEV1), in general population samples by genome-wide association studies. However, in vivo evidence connecting Hhip to age-related FEV1 decline and emphysema development is lacking. Herein, using Hhip heterozygous mice (Hhip(+/-)), we observed increased lung compliance and spontaneous emphysema in Hhip(+/-) mice starting at 10 mo of age. This increase was preceded by increases in oxidative stress levels in the lungs of Hhip(+/-) vs. Hhip(+/+) mice. To our knowledge, these results provide the first line of evidence that HHIP is involved in maintaining normal lung function and alveolar structures. Interestingly, antioxidant N-acetyl cysteine treatment in mice starting at age of 5 mo improved lung function and prevented emphysema development in Hhip(+/-) mice, suggesting that N-acetyl cysteine treatment limits the progression of age-related emphysema in Hhip(+/-) mice. Therefore, reduced lung function and age-related spontaneous emphysema development in Hhip(+/-) mice may be caused by increased oxidative stress levels in murine lungs as a result of haploinsufficiency of Hhip. PMID:27444019

  14. Senescent cells: SASPected drivers of age-related pathologies.

    PubMed

    Ovadya, Yossi; Krizhanovsky, Valery

    2014-12-01

    The progression of physiological ageing is driven by intracellular aberrations including telomere attrition, genomic instability, epigenetic alterations and loss of proteostasis. These in turn damage cells and compromise their functionality. Cellular senescence, a stable irreversible cell-cycle arrest, is elicited in damaged cells and prevents their propagation in the organism. Under normal conditions, senescent cells recruit the immune system which facilitates their removal from tissues. Nevertheless, during ageing, tissue-residing senescent cells tend to accumulate, and might negatively impact their microenvironment via profound secretory phenotype with pro-inflammatory characteristics, termed senescence-associated secretory phenotype (SASP). Indeed, senescent cells are mostly abundant at sites of age-related pathologies, including degenerative disorders and malignancies. Interestingly, studies on progeroid mice indicate that selective elimination of senescent cells can delay age-related deterioration. This suggests that chronic inflammation induced by senescent cells might be a main driver of these pathologies. Importantly, senescent cells accumulate as a result of deficient immune surveillance, and their removal is increased upon the use of immune stimulatory agents. Insights into mechanisms of senescence surveillance could be combined with current approaches for cancer immunotherapy to propose new preventive and therapeutic strategies for age-related diseases. PMID:25217383

  15. Age at first reproduction explains rate variation in the strepsirrhine molecular clock

    PubMed Central

    Tsantes, C.; Steiper, M. E.

    2009-01-01

    Although the molecular clock hypothesis posits that the rate of molecular change is constant over time, there is evidence that rates vary among lineages. Some of the strongest evidence for variable molecular rates comes from the primates; e.g., the “hominoid slowdown.” These rate differences are hypothesized to correlate with certain species attributes, such as generation time and body size. Here, we examine rates of molecular change in the strepsirrhine suborder of primates and test whether body size or age at first reproduction (a proxy for generation time) explains patterns of rate variation better than a null model where the molecular clock is independent of these factors. To examine these models, we analyzed DNA sequences from four pairs of recently diverged strepsirrhine sister taxa to estimate molecular rates by using sign tests, likelihood ratio tests, and regression analyses. Our analysis does not support a model where body weight or age at first reproduction strongly influences rates of molecular evolution across mitochondrial and nuclear sites. Instead, our analysis supports a model where age at first reproduction influences neutral evolution in the nuclear genome. This study supports the generation time hypothesis for rate variation in the nuclear molecular clock. Molecular clock variation due to generation time may help to resolve the discordance between molecular and paleontological estimates for divergence date estimates in primate evolution. PMID:19841267

  16. Aging-associated formaldehyde-induced norepinephrine deficiency contributes to age-related memory decline.

    PubMed

    Mei, Yufei; Jiang, Chun; Wan, You; Lv, Jihui; Jia, Jianping; Wang, Xiaomin; Yang, Xu; Tong, Zhiqian

    2015-08-01

    A norepinephrine (NE) deficiency has been observed in aged rats and in patients with Alzheimer's disease and is thought to cause cognitive disorder. Which endogenous factor induces NE depletion, however, is largely unknown. In this study, we investigated the effects of aging-associated formaldehyde (FA) on the inactivation of NE in vitro and in vivo, and on memory behaviors in rodents. The results showed that age-related DNA demethylation led to hippocampal FA accumulation, and when this occurred, the hippocampal NE content was reduced in healthy male rats of different ages. Furthermore, biochemical analysis revealed that FA rapidly inactivated NE in vitro and that an intrahippocampal injection of FA markedly reduced hippocampal NE levels in healthy adult rats. Unexpectedly, an injection of FA (at a pathological level) or 6-hydroxydopamine (6-OHDA, a NE depletor) can mimic age-related NE deficiency, long-term potentiation (LTP) impairments, and spatial memory deficits in healthy adult rats. Conversely, an injection of NE reversed age-related deficits in both LTP and memory in aged rats. In agreement with the above results, the senescence-accelerated prone 8 (SAMP8) mice also exhibited a severe deficit in LTP and memory associated with a more severe NE deficiency and FA accumulation, when compared with the age-matched, senescence-resistant 1 (SAMR1) mice. Injection of resveratrol (a natural FA scavenger) or NE into SAMP8 mice reversed FA accumulation and NE deficiency and restored the magnitude of LTP and memory. Collectively, these findings suggest that accumulated FA is a critical endogenous factor for aging-associated NE depletion and cognitive decline. PMID:25866202

  17. Aging-associated formaldehyde-induced norepinephrine deficiency contributes to age-related memory decline

    PubMed Central

    Mei, Yufei; Jiang, Chun; Wan, You; Lv, Jihui; Jia, Jianping; Wang, Xiaomin; Yang, Xu; Tong, Zhiqian

    2015-01-01

    A norepinephrine (NE) deficiency has been observed in aged rats and in patients with Alzheimer’s disease and is thought to cause cognitive disorder. Which endogenous factor induces NE depletion, however, is largely unknown. In this study, we investigated the effects of aging-associated formaldehyde (FA) on the inactivation of NE in vitro and in vivo, and on memory behaviors in rodents. The results showed that age-related DNA demethylation led to hippocampal FA accumulation, and when this occurred, the hippocampal NE content was reduced in healthy male rats of different ages. Furthermore, biochemical analysis revealed that FA rapidly inactivated NE in vitro and that an intrahippocampal injection of FA markedly reduced hippocampal NE levels in healthy adult rats. Unexpectedly, an injection of FA (at a pathological level) or 6-hydroxydopamine (6-OHDA, a NE depletor) can mimic age-related NE deficiency, long-term potentiation (LTP) impairments, and spatial memory deficits in healthy adult rats. Conversely, an injection of NE reversed age-related deficits in both LTP and memory in aged rats. In agreement with the above results, the senescence-accelerated prone 8 (SAMP8) mice also exhibited a severe deficit in LTP and memory associated with a more severe NE deficiency and FA accumulation, when compared with the age-matched, senescence-resistant 1 (SAMR1) mice. Injection of resveratrol (a natural FA scavenger) or NE into SAMP8 mice reversed FA accumulation and NE deficiency and restored the magnitude of LTP and memory. Collectively, these findings suggest that accumulated FA is a critical endogenous factor for aging-associated NE depletion and cognitive decline. PMID:25866202

  18. Age-related priming effects in social judgments.

    PubMed

    Hess, T M; McGee, K A; Woodburn, S M; Bolstad, C A

    1998-03-01

    Two experiments investigated adult age differences in the impact of previously activated (and thus easily accessible) trait-related information on judgments about people. The authors hypothesized that age-related declines in the efficiency of controlled processing mechanisms during adulthood would be associated with increased susceptibility to judgment biases associated with such information. In each study, different-aged adults made impression judgments about a target, and assimilation of these judgments to trait constructs activated in a previous, unrelated task were examined. Consistent with the authors' hypotheses, older adults were likely to form impressions that were biased toward the primed trait constructs. In contrast, younger adults exhibited greater awareness of the primed information and were more likely to correct for its perceived influence, especially when distinctive contextual cues regarding the source of the primes were available. PMID:9533195

  19. Age-related percutaneous penetration part 1: skin factors.

    PubMed

    Konda, S; Meier-Davis, S R; Cayme, B; Shudo, J; Maibach, H I

    2012-05-01

    Changes in the skin that occur in the elderly may put them at increased risk for altered percutaneous penetration from pharmacotherapy along with potential adverse effects. Skin factors that may have a role in age-related percutaneous penetration include blood flow, pH, skin thickness, hair and pore density, and the content and structure of proteins, glycosaminoglycans (GAGs), water, and lipids. Each factor is examined as a function of increasing age along with its potential impact on percutaneous penetration. Additionally, topical drugs that successfully overcome the barrier function of the skin can still fall victim to cutaneous metabolism, thereby producing metabolites that may have increased or decreased activity. This overview discusses the current data and highlights the importance of further studies to evaluate the impact of skin factors in age-related percutaneous penetration. PMID:22622279

  20. Age-related macular degeneration: Evidence of a major gene

    SciTech Connect

    Bhatt, S.; Warren, C.; Yang, H.

    1994-09-01

    Age-related macular degeneration is a major cause of blindness in developing countries. It remains a very poorly understood disorder. Although environmental and genetic factors have been implicated in its pathogenesis, none have been firmly implicated. The purpose of this study was to use pedigree analysis to evaluate the possible role of a major gene as a determinant of familial aggregation. Information was collected regarding occupation, smoking, sun exposure, associated medical problems and family history. 50 probands with age-related macular degeneration (ARMD) and 39 age, race and sex-matched controls were included in the study. In the ARMD group 15/50 (30%) of probands reported a positive family history; 22 out of 222 first degree relatives over age 60 were reported to be affected. In the control groups, none of the 138 first degree relatives over age 50 had a history of ARMD. This difference is statistically significant (p = 0.0003), indicating that genetic factors may play an important role in the pathogenesis of ARMD. In the ARMD group more siblings as compared to parents (16/127 vs. 5/82) were affected. 5/50 (10%) of the ARMD probands also gave a history of a second degree relative affected with ARMD, compared to none known among the relatives of controls. Data from 50 pedigrees were analyzed by complex segregation analysis under a class A regressive logistic model using the REGD program implemented in the SAGE package. Preliminary results allow rejection of a polygenic model and suggest there is a major gene for ARMD in these families. The inheritance model most compatible with the observed familial aggregation is autosomal recessive. In conclusion, these results are suggestive of a major gene effect in the etiology of ARMD. Identification of a major gene effect is a first step to further pursue linkage analysis and to search for the gene(s) involved in the causation of ARMD.

  1. Variation in the corticotropin-releasing hormone receptor 1 (CRHR1) gene modulates age effects on working memory.

    PubMed

    Grimm, Simone; Gärtner, Matti; Fuge, Philipp; Fan, Yan; Weigand, Anne; Feeser, Melanie; Aust, Sabine; Heekeren, Hauke R; Jacobs, Arthur; Heuser, Isabella; Bajbouj, Malek

    2015-02-01

    Decline in working memory (WM) functions during aging has been associated with hippocampal dysfunction mediated by age-related changes to the corticotropin-releasing hormone (CRH) system. Recent reports suggest that GG-homozygous individuals of single nucleotide polymorphisms (rs110402 and rs242924) in the CRH receptor 1 (CRHR1) gene show increased stress vulnerability and decreased BOLD responses in WM relevant regions. However, until now, no study investigated the interaction effects of variation in the CRHR1 gene and age on individual differences in WM. Here, young, middle-aged and old subjects (N = 466) were genotyped for rs110402 and rs242924 within the CRHR1 gene and an n-back task was used to investigate the hypothesis that vulnerable genotypes (GG-homozygotes) would show impaired WM functions that might be magnified by increased CRH production with advancing age. Our results show an impact of genotype already in middle-age with significantly better performance in AT-carriers. Working memory performance in AT-carriers did not differ between young and middle-aged subjects, but was significantly impaired in old age. In GG-homozygotes, severe working memory dysfunction occurred already in middle age. Our data indicate that GG-homozygotes of CRHR1 rs110402 and rs242924 represent a genetically driven subtype of early WM impairments due to alterations in hippocampal CRHR1 activation. Early interventions that have proven effective in delaying cognitive decline appear to be particularly important for these subjects at risk for premature memory decline, who are in the prime of their personal and professional lives. PMID:25541005

  2. The role of telomeres and vitamin D in cellular aging and age-related diseases.

    PubMed

    Pusceddu, Irene; Farrell, Christopher-John L; Di Pierro, Angela Maria; Jani, Erika; Herrmann, Wolfgang; Herrmann, Markus

    2015-10-01

    Aging is a complex biological process characterized by a progressive decline of organ functions leading to an increased risk of age-associated diseases and death. Decades of intensive research have identified a range of molecular and biochemical pathways contributing to aging. However, many aspects regarding the regulation and interplay of these pathways are insufficiently understood. Telomere dysfunction and genomic instability appear to be of critical importance for aging at a cellular level. For example, age-related diseases and premature aging syndromes are frequently associated with telomere shortening. Telomeres are repetitive nucleotide sequences that together with the associated sheltrin complex protect the ends of chromosomes and maintain genomic stability. Recent studies suggest that micronutrients, such as vitamin D, folate and vitamin B12, are involved in telomere biology and cellular aging. In particular, vitamin D is important for a range of vital cellular processes including cellular differentiation, proliferation and apoptosis. As a result of the multiple functions of vitamin D it has been speculated that vitamin D might play a role in telomere biology and genomic stability. Here we review existing knowledge about the link between telomere biology and cellular aging with a focus on the role of vitamin D. We searched the literature up to November 2014 for human studies, animal models and in vitro experiments that addressed this topic. PMID:25803084

  3. The Experience of Age-Related Macular Degeneration

    ERIC Educational Resources Information Center

    Wong, Elaine Y. H.; Guymer, Robyn H.; Hassell, Jennifer B.; Keeffe, Jill E.

    2004-01-01

    This qualitative article describes the impact of age-related macular degeneration (ARMD) among 15 participants: how a person makes sense of ARMD, the effect of ARMD on the person's quality of life, the psychological disturbances associated with the limitations of ARMD, and the influence of ARMD on social interactions. Such in-depth appreciation of…

  4. Soybean β-Conglycinin Prevents Age-Related Hearing Impairment

    PubMed Central

    Tanigawa, Tohru; Shibata, Rei; Kondo, Kazuhisa; Katahira, Nobuyuki; Kambara, Takahiro; Inoue, Yoko; Nonoyama, Hiroshi; Horibe, Yuichiro; Ueda, Hiromi; Murohara, Toyoaki

    2015-01-01

    Obesity-related complications are associated with the development of age-related hearing impairment. β-Conglycinin (β-CG), one of the main storage proteins in soy, offers multiple health benefits, including anti-obesity and anti-atherosclerotic effects. Here, to elucidate the potential therapeutic application of β-CG, we investigated the effect of β-CG on age-related hearing impairment. Male wild-type mice (age 6 months) were randomly divided into β-CG-fed and control groups. Six months later, the body weight was significantly lower in β-CG-fed mice than in the controls. Consumption of β-CG rescued the hearing impairment observed in control mice. Cochlear blood flow also increased in β-CG-fed mice, as did the expression of eNOS in the stria vascularis (SV), which protects vasculature. β-CG consumption also ameliorated oxidative status as assessed by 4-HNE staining. In the SV, lipofuscin granules of marginal cells and vacuolar degeneration of microvascular pericytes were decreased in β-CG-fed mice, as shown by transmission electron microscopy. β-CG consumption prevented loss of spiral ganglion cells and reduced the frequencies of lipofuscin granules, nuclear invaginations, and myelin vacuolation. Our observations indicate that β-CG ameliorates age-related hearing impairment by preserving cochlear blood flow and suppressing oxidative stress. PMID:26348726

  5. The Relative Age Effect in Elite Sport: The French Case

    ERIC Educational Resources Information Center

    Delorme, Nicolas; Boiche, Julie; Raspaud, Michel

    2009-01-01

    The relative age effect (RAE) is considered a common phenomenon in elite sport. However, it has not been examined systematically in previous research, and the mechanisms likely to generate or to limit such an effect are little understood. This paper investigates the prevalence of the RAE in French professional championship-level players, taking…

  6. Nutritional antioxidants and age-related cataract and maculopathy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Loss of vision is the second greatest, next to death, fear among the elderly. Age-related cataract (ARC) and maculopathy (ARM) are two major causes of blindness worldwide. There are several important reasons to study relationships between risk for ARC/ARM and nutrition: (1) because it is likely that...

  7. Age-Related Factors in Second Language Acquisition.

    ERIC Educational Resources Information Center

    Twyford, Charles William

    The convergence of several lines of psycholinguistic and sociolinguistic research suggests possible explanations for age-related influences on language acquisition. These factors, which include cognitive development, sociocultural context, affective factors, and language input, can be helpful to language educators. By being alert to the cognitive…

  8. Variation in body condition indices of crimson finches by sex, breeding stage, age, time of day, and year

    PubMed Central

    Milenkaya, Olga; Weinstein, Nicole; Legge, Sarah; Walters, Jeffrey R.

    2013-01-01

    Body condition indices are increasingly applied in conservation to assess habitat quality, identify stressed populations before they decline, determine effects of disturbances, and understand mechanisms of declines. To employ condition indices in this manner, we need first to understand their baseline variability and sources of variation. Here, we used crimson finches (Neochmia phaeton), a tropical passerine, to describe the variation in seven commonly used condition indices by sex, age, breeding stage, time of day, and year. We found that packed cell volume, haemoglobin, total plasma protein, and scaled mass were all significantly affected by an interaction between sex and breeding stage. Furcular fat varied by sex and breeding stage and also trended by year, scaled mass showed a positive trend with age and varied by time of day, and haemoglobin additionally varied by year. Pectoral muscle scores varied and heterophil to lymphocyte ratio trended only by year. Year effects might reflect a response to annual variation in environmental conditions; therefore, those indices showing year effects may be especially worthy of further investigation of their potential for conservation applications. Pectoral muscle scores and heterophil to lymphocyte ratio may be particularly useful due to the lack of influence of other variables on them. For the other indices, the large variation that can be attributed to individual covariates, such as sex and breeding stage, suggests that one should not interpret the physiological condition of an individual as measured by these indices from their absolute value. Instead, the condition of an individual should be interpreted relative to conspecifics by sex, breeding stage, and possibly age. PMID:27293604

  9. Frequency variations of the earth's obliquity and the 100-kyr ice-age cycles

    NASA Technical Reports Server (NTRS)

    Liu, Han-Shou

    1992-01-01

    Changes in the earth's climate are induced by variations in the earth's orbital parameters which modulate the seasonal distribution of solar radiation. Periodicities in the geological climate record with cycles of 100, 41, and 23 kyr have been linked with changes in obliquity, eccentricity, and precession of the equinoxes. The effect of variations of eccentricity during a 100 kyr period is weak relative to the signals from obliquity and precession variations and it may therefore be expected that the 100 kyr signal in the climate record would be of low intensity. However, this signal dominates the climate record and internal nonlinear processes within the climate system have previously been proposed to account for this fact. The author shows that variations in the frequency of the obliquity cycle can give rise to strong 100-kyr forcing of climate.

  10. Age-related penetrance of hereditary atypical hemolytic uremic syndrome.

    PubMed

    Sullivan, Maren; Rybicki, Lisa A; Winter, Aurelia; Hoffmann, Michael M; Reiermann, Stefanie; Linke, Hannah; Arbeiter, Klaus; Patzer, Ludwig; Budde, Klemens; Hoppe, Bernd; Zeier, Martin; Lhotta, Karl; Bock, Andreas; Wiech, Thorsten; Gaspert, Ariana; Fehr, Thomas; Woznowski, Magdalena; Berisha, Gani; Malinoc, Angelica; Goek, Oemer-Necmi; Eng, Charis; Neumann, Hartmut P H

    2011-11-01

    Hereditary atypical hemolytic uremic syndrome (aHUS), a dramatic disease frequently leading to dialysis, is associated with germline mutations of the CFH, CD46, or CFI genes. After identification of the mutation in an affected aHUS patient, single-site gene testing of relatives is the preventive care perspective. However, clinical data for family counselling are scarce. From the German-Speaking-Countries-aHUS-Registry, 33 index patients with mutations were approached for permission to offer relatives screening for their family-specific mutations and to obtain demographic and clinical data. Mutation screening was performed using direct sequencing. Age-adjusted penetrance of aHUS was calculated for each gene in index cases and in mutation-positive relatives. Sixty-one relatives comprising 41 parents and 20 other relatives were enrolled and mutations detected in 31/61. In total, 40 research participants had germline mutations in CFH, 19 in CD46 and in 6 CFI. Penetrance at age 40 was markedly reduced in mutation-positive relatives compared to index patients overall with 10% versus 67% (P < 0.001); 6% vs. 67% (P < 0.001) in CFH mutation carriers and 21% vs. 70% (P= 0.003) in CD46 mutation carriers. Age-adjusted penetrance for hereditary aHUS is important to understand the disease, and if replicated in the future, for genetic counselling. PMID:21906045

  11. Motor Control and Aging: Links to Age-Related Brain Structural, Functional, and Biochemical Effects

    PubMed Central

    Seidler, Rachael D.; Bernard, Jessica A.; Burutolu, Taritonye B.; Fling, Brett W.; Gordon, Mark T.; Gwin, Joseph T.; Kwak, Youngbin; Lipps, David B.

    2009-01-01

    Although connections between cognitive deficits and age-associated brain differences have been elucidated, relationships with motor performance are less well understood. Here, we broadly review age-related brain differences and motor deficits in older adults in addition to cognition-action theories. Age-related atrophy of the motor cortical regions and corpus callosum may precipitate or coincide with motor declines such as balance and gait deficits, coordination deficits, and movement slowing. Correspondingly, degeneration of neurotransmitter systems—primarily the dopaminergic system—may contribute to age-related gross and fine motor declines, as well as to higher cognitive deficits. In general, older adults exhibit involvement of more widespread brain regions for motor control than young adults, particularly the prefrontal cortex and basal ganglia networks. Unfortunately these same regions are the most vulnerable to age-related effects, resulting in an imbalance of “supply and demand”. Existing exercise, pharmaceutical, and motor training interventions may ameliorate motor deficits in older adults. PMID:19850077

  12. Prevalence of age-related macular degeneration among the elderly

    PubMed Central

    Rasoulinejad, Seyed Ahmad; Zarghami, Amin; Hosseini, Seyed Reza; Rajaee, Neda; Rasoulinejad, Seyed Elahe; Mikaniki, Ebrahim

    2015-01-01

    Background: Age-related macular degeneration (AMD) is the leading cause of visual impairment and blindness in elderly population in the developing countries. Previous epidemiological studies revealed various potential modifiable risk factors for this disease. The purpose of this study was to evaluate the prevalence of AMD among elderly living in Babol, North of Iran. Methods: The study population of this cross-sectional study came from the Amirkola Health and Ageing Project (AHAP), the first comprehensive cohort study of the health of people aged 60 years and over in Amirkola, North of Iran. The prevalence of AMD was estimated and its risk was determined using logistic regression analysis (LRA) with regard to variables such as smoking, hyperlipidemia, hypertension and diabetes. Results: Five hundred and five participants with mean age of 71.55±5.9 (ranged 60-89) years entered the study. The prevalence of AMD was 17.6%. There was a significant association between AMD and smoking (P<0.001) but no association was seen with AMD and age, level of education, history of hyperlipidemia, hypertension and diabetes. Multiple LRAs revealed that smoking increased AMD by odds ratio of 5.03 (95% confidence interval 2.47-10.23 p<0.001) as compared to nonsmokers Conclusion: According to our findings, the prevalence of AMD was relatively high and smoking increased the risk of AMD in the elderly population. PMID:26644880

  13. Age-related differences in electroencephalogram connectivity and network topology.

    PubMed

    Knyazev, Gennady G; Volf, Nina V; Belousova, Ludmila V

    2015-05-01

    To better understand age-related differences in brain function and behavior, connectivity between brain regions was estimated from electroencephalogram source time series in eyes closed versus eyes open resting condition. In beta band, decrease of connectivity upon eyes opening was more pronounced in younger than in older participants. The extent of this decrease was associated with reaction time in attention tasks, and this relationship was fully mediated by participants' age, implying that physiological processes, which lead to age-related slowing, include changes in beta reactivity. Graph-theoretical analysis showed a decrease of modularity and clustering in beta and gamma band networks in older adults, implying that age makes brain networks more random. The overall number of nodes identified as hubs in posterior cortical regions decreased in older participants. At the same time, increase of connectedness of anterior nodes, probably reflecting compensatory activation of the anterior attentional system, was observed in beta-band network of older adults. These findings show that normal aging mostly affects interactions in beta band, which are probably involved in attentional processes. PMID:25766772

  14. Striking effect of time variation in the estimation of groundwater age in the Wairarapa valley

    NASA Astrophysics Data System (ADS)

    Petrus, Karine; Toews, Michael; Daughney, Christopher; Cornaton, Fabien

    2014-05-01

    The Wairarapa Valley exhibits complex interactions between its rivers and shallow aquifers. With agriculture being an essential part of the region the risk of contamination and depletion of groundwater exists. In order to assist with water resource management in the region, we can do predictions with the help of numerical models. Among these predictions, the evaluation of groundwater age is critical for decision making. This project builds on work done by Greater Wellington Regional Council and will focus on the Wairarapa Valley. The aim of this study is to evaluate the age of the groundwater in the Wairarapa region. Investigations have already been done thanks to hydrochemistry. However radiometric age can be misleading in the sense that it does not consider the mixing process in the motion of groundwater particules. Therefore another approach can be considered .This latter is physic based by considering the age as a property that we transport through two main processes: advection at a macroscopic scale and diffusion at a microscopic scale. The determination of the distribution age by this approach has already been done for the Lake Rotorua but in the steady state case (cf Daughney). The unique contribution of the present study is to estimate the changes in groundwater age distribution through time within the region. Indeed transient simulations are needed to explicitly account for seasonally variable rainfall and pumping wells. This affects the simulated flow solution and then the simulated age solution. In order to solve numerically the transport of age distribution we have chosen to use the Time Marching Laplace Transform Galerkin technique which has been developed in a research code by Fabien Cornaton. The obtained results depict that temporal variations in groundwater age are present and have important implication for resource management

  15. Age-related somatic mutations in the cancer genome

    PubMed Central

    Milholland, Brandon; Auton, Adam; Suh, Yousin; Vijg, Jan

    2015-01-01

    Aging is associated with an increased risk of cancer, possibly in part because of an age-related increase in mutations in normal tissues. Due to their extremely low abundance, somatic mutations in normal tissues frequently escape detection. Tumors, as clonal expansions of single cells, can provide information about the somatic mutations present in these cells prior to tumorigenesis. Here, we used data from The Cancer Genome Atlas (TCGA), to systematically study the frequency and spectrum of somatic mutations in a total of 6,969 patients and 34 different tumor types as a function of the age of the patient. After using linear modeling to control for the age structure of different tumor types, we found that the number of identified somatic mutations increases exponentially with age. Using additional data from the literature, we found that accumulation of somatic mutations is associated with cell division rate, cancer risk and cigarette smoking, with the latter also associated with a distinct spectrum of mutations. Our results confirm that aging is associated with the accumulation of somatic mutations, and strongly suggest that the level of genome instability of normal cells, modified by both endogenous and environmental factors, is the main risk factor for cancer. PMID:26384365

  16. The origins of age-related proinflammatory state.

    PubMed

    Ferrucci, Luigi; Corsi, Annamaria; Lauretani, Fulvio; Bandinelli, Stefania; Bartali, Benedetta; Taub, Dennis D; Guralnik, Jack M; Longo, Dan L

    2005-03-15

    We hypothesized that the rising levels of inflammatory markers with aging is explained by cardiovascular risk factors and morbidity becoming progressively more prevalent in older persons. Information on inflammatory markers, cardiovascular risk factors, and diseases was collected in 595 men and 748 women sampled from the general population (age, 20-102 years). In both men and women, older age was associated with higher levels of interleukin-6 (IL-6), IL-1 receptor antagonist (IL-1ra), IL-18, C-reactive protein (CRP), and fibrinogen, while soluble IL-6 receptor (sIL-6r) increased significantly with age only in men. Adjusting for cardiovascular risk factors and morbidity, the age regression coefficients became substantially smaller in models predicting IL-6, IL-1ra, IL-18, and fibrinogen and larger in the model predicting sIL6r. Adjustment for cardiovascular morbidity substantially reduced the effect of age on CRP in men but not in women. Findings were confirmed in a subgroup of 51 men and 45 women with low risk profile and no cardiovascular morbidity. Part of the "proinflammatory state" in older persons is related to the high prevalence of cardiovascular risk factor and morbidity. PMID:15572589

  17. The Laboratory Rat: Relating Its Age With Human's

    PubMed Central

    Sengupta, Pallav

    2013-01-01

    By late 18th or early 19th century, albino rats became the most commonly used experimental animals in numerous biomedical researches, as they have been recognized as the preeminent model mammalian system. But, the precise correlation between age of laboratory rats and human is still a subject of debate. A number of studies have tried to detect these correlations in various ways, But, have not successfully provided any proper association. Thus, the current review attempts to compare rat and human age at different phases of their life. The overall findings indicate that rats grow rapidly during their childhood and become sexually mature at about the sixth week, but attain social maturity 5-6 months later. In adulthood, every day of the animal is approximately equivalent to 34.8 human days (i.e., one rat month is comparable to three human years). Numerous researchers performed experimental investigations in albino rats and estimated, in general, while considering their entire life span, that a human month resembles every-day life of a laboratory rat. These differences signify the variations in their anatomy, physiology and developmental processes, which must be taken into consideration while analyzing the results or selecting the dose of any research in rats when age is a crucial factor. PMID:23930179

  18. Age-related changes in mouse bone permeability.

    PubMed

    Rodriguez-Florez, Naiara; Oyen, Michelle L; Shefelbine, Sandra J

    2014-03-21

    The determination of lacunar-canalicular permeability is essential for understanding local fluid flow in bone, which may indicate how bone senses changes in the mechanical environment to regulate mechano-adaptation. The estimates of lacunar-canalicular permeability found in the literature vary by up to eight orders of magnitude, and age-related permeability changes have not been measured in non-osteonal mouse bone. The objective of this study is to use a poroelastic approach based on nanoindentation data to characterize lacunar-canalicular permeability in murine bone as a function of age. Nine wild type C57BL/6 mice of different ages (2, 7 and 12 months) were used. Three tibiae from each age group were embedded in epoxy resin, cut in half and indented in the longitudinal direction in the mid-cortex using two spherical fluid indenter tips (R=238 μm and 500 μm). Results suggest that the lacunar-canalicular intrinsic permeability of mouse bone decreases from 2 to 7 months, with no significant changes from 7 to 12 months. The large indenter tip imposed larger contact sizes and sampled larger ranges of permeabilities, particularly for the old bone. This age-related difference in the distribution was not seen for indents with the smaller radius tip. We conclude that the small tip effectively measured lacunar-canalicular permeability, while larger tip indents were influenced by vascular permeability. Exploring the age-related changes in permeability of bone measured by nanoindentation will lead to a better understanding of the role of fluid flow in mechano-transduction. This understanding may help indicate alterations in bone adaptation and remodeling. PMID:24433671

  19. Age and gender related differences in aortic blood flow

    NASA Astrophysics Data System (ADS)

    Enevoldsen, Marie Sand; Pedersen, Mads Møller; Hemmsen, Martin Christian; Lönn, Lars; Henneberg, Kaj-Åge; Jensen, Jørgen Arendt

    2012-03-01

    The abdominal aorta (AA) is predisposed to development of abdominal aneurysms (AAA), a focal dilatation with fatal consequences if left untreated. The blood flow patterns is thought to play an important role in the development of AAA. The purpose of this work is to investigate the blood flow patterns within a group of healthy volunteers (six females, eight males) aged 23 to 76 years to identify changes and differences related to age and gender. The healthy volunteers were categorized by gender (male/female) and age (below/above 35 years). Subject-specific flow and geometry data were acquired using the research interface on a Profocus ultrasound scanner (B-K Medical, Herlev, Denmark; segmentation of 3D magnetic resonance angiography (Magnetom Trio, Siemens Healthcare, Erlangen, Germany). The largest average diameter was among the elderly males (19.7 (+/- 1.33) mm) and smallest among the young females (12.4 (+/- 0.605) mm). The highest peak systolic velocity was in the young female group (1.02 (+/- 0.336) m/s) and lowest in the elderly male group (0.836 (+/- 0.127) m/s). A geometrical change with age was observed as the AA becomes more bended with age. This also affects the blood flow velocity patterns, which are markedly different from young to elderly. Thus, changes in blood flow patterns in the AA related to age and gender are observed. Further investigations are needed to determine the relation between changes in blood flow patterns and AAA development.

  20. Age-Related Changes in Skeletal Muscle of Cattle.

    PubMed

    Costagliola, A; Wojcik, S; Pagano, T B; De Biase, D; Russo, V; Iovane, V; Grieco, E; Papparella, S; Paciello, O

    2016-03-01

    Sarcopenia, the age-related loss of muscle mass and strength, is a multifactorial condition that represents a major healthcare concern for the elderly population. Although its morphologic features have been extensively studied in humans, animal models, and domestic and wild animals, only a few reports about spontaneous sarcopenia exist in other long-lived animals. In this work, muscle samples from 60 healthy Podolica-breed old cows (aged 15-23 years) were examined and compared with muscle samples from 10 young cows (3-6 years old). Frozen sections were studied through standard histologic and histoenzymatic procedures, as well as by immunohistochemistry, immunofluorescence, and Western blot analysis. The most prominent age-related myopathic features seen in the studied material included angular fiber atrophy (90% of cases), mitochondrial alterations (ragged red fibers, 70%; COX-negative fibers, 60%), presence of vacuolated fibers (75%), lymphocytic (predominantly CD8+) inflammation (40%), and type II selective fiber atrophy (40%). Immunohistochemistry revealed increased expression of major histocompatibility complex I in 36 cases (60%) and sarcoplasmic accumulations of β-amyloid precursor protein-positive material in 18 cases (30%). In aged cows, muscle atrophy was associated with accumulation of myostatin. Western blot analysis indicated increased amount of both proteins-myostatin and β-amyloid precursor protein-in muscles of aged animals compared with controls. These findings confirm the presence of age-related morphologic changes in cows similar to human sarcopenia and underline the possible role of amyloid deposition and subsequent inflammation in muscle senescence. PMID:26869152

  1. Hypermnesia: age-related differences between young and older adults.

    PubMed

    Widner, R L; Otani, H; Smith, A D

    2000-06-01

    Hypermnesia is a net improvement in memory performance that occurs across tests in a multitest paradigm with only one study session. Our goal was to identify possible age-related differences in hypermnesic recall. We observed hypermnesia for young adults using verbal (Experiment 1) as well as pictorial (Experiment 2) material, but no hypermnesia for older adults in either experiment. We found no age-related difference in reminiscence (Experiments 1 and 2), though there was a substantial difference in intertest forgetting (Experiments 1 and 2). Older, relative to young, adults produced more forgetting, most of which occurred between Tests 1 and 2 (Experiments 1 and 2). Furthermore, older, relative to young, adults produced more intrusions. We failed to identify a relationship between intrusions and intertest forgetting. We suggest that the age-related difference in intertest forgetting may be due to less efficient reinstatement of cues at test by older adults. The present findings reveal that intertest forgetting plays a critical role in hypermnesic recall, particularly for older adults. PMID:10946539

  2. Age-Related Effects on Future Mental Time Travel

    PubMed Central

    Anelli, Filomena; Ciaramelli, Elisa; Arzy, Shahar; Frassinetti, Francesca

    2016-01-01

    Mental time travel (MTT), the ability to travel mentally back and forward in time in order to reexperience past events and preexperience future events, is crucial in human cognition. As we move along life, MTT may be changed accordingly. However, the relation between re- and preexperiencing along the lifespan is still not clear. Here, young and older adults underwent a psychophysical paradigm assessing two different components of MTT: self-projection, which is the ability to project the self towards a past or a future location of the mental time line, and self-reference, which is the ability to determine whether events are located in the past or future in reference to that given self-location. Aged individuals performed worse in both self-projection to the future and self-reference to future events compared to young individuals. In addition, aging decreased older adults' preference for personal compared to nonpersonal events. These results demonstrate the impact of MTT and self-processing on subjective time processing in healthy aging. Changes in memory functions in aged people may therefore be related not only to memory per se, but also to the relations of memory and self. PMID:27144031

  3. Age and comorbidity considerations related to radiotherapy and chemotherapy administration.

    PubMed

    Rodrigues, George; Sanatani, Michael

    2012-10-01

    Oncological treatment decision-making is a highly complex enterprise integrating multiple patient, tumor, treatment, and professional factors with the available medical evidence. This management complexity can be exacerbated by the interplay of patient age and comorbid non-cancer conditions that can affect patient quality of life, treatment tolerance, and survival outcomes. Given the expected increase in median age (and associated comorbidity burden) of Western populations over the next few decades, the use of evidence-based therapies that appropriately balance treatment intensity and tolerability to achieve the desired goal of treatment (radical, adjuvant, salvage, or palliative) will be increasingly important to health care systems, providers, and patients. In this review, we highlight the evidence related to age and comorbidity, as it relates to radiotherapy and chemotherapy decision making. We will address evidence as it relates to age and comorbidity considerations separately and also the interplay between the factors. Clinical considerations to adapt radiation and/or chemotherapy treatment to deal with comorbidity challenges will be discussed. Knowledge gaps, future research, and clinical recommendation in this increasingly important field are highlighted as well. PMID:22985810

  4. The aging correlation (RH + t): Relative humidity (%) + temperature (deg C)

    NASA Technical Reports Server (NTRS)

    Cuddihy, E. F.

    1986-01-01

    An aging correlation between corrosion lifetime, and relative humidity RH (%) and temperature t (C) has been reported in the literature. This aging correlation is a semi-log plot of corrosion lifetime on the log scale versus the interesting summation term RH(%) + t(C) on the linear scale. This empirical correlation was derived from observation of experimental data trends and has been referred to as an experimental law. Using electrical resistivity data of polyvinyl butyral (PVB) measured as a function of relative humidity and temperature, it was found that the electrical resistivity could be expressed as a function of the term RH(%) t(C). Thus, if corrosion is related to leakage current through an organic insulator, which, in turn, is a function of RH and t, then some partial theoretical validity for the correlation is indicated. This article describes the derivation of the term RH(%) t(C) from PVB electrical resistivity data.

  5. Genetic and Environmental Underpinnings to Age-Related Ocular Diseases

    PubMed Central

    Seddon, Johanna M.

    2013-01-01

    Age-related macular degeneration (AMD), cataract, glaucoma and diabetic retinopathy are common causes of visual loss. Both environmental and genetic factors contribute to the development of these diseases. The modifiable factors related to some of these age-related and visually threatening diseases are smoking, obesity, and dietary factors, and a cardiovascular risk profile. Many common and a few rare genetic factors are associated with AMD. The role of genetic variants for the other diseases are less clear. Interactions between environmental, therapeutic, and genetic factors are being explored. Knowledge of genetic risk and environmental factors, especially for AMD, has grown markedly over the past 2.5 decades and has led to some sight-saving approaches in preventive management. PMID:24335064

  6. Age-related macular degeneration: Complement in action.

    PubMed

    van Lookeren Campagne, Menno; Strauss, Erich C; Yaspan, Brian L

    2016-06-01

    The complement system plays a key role in host-defense against common pathogens but must be tightly controlled to avoid inflammation and tissue damage. Polymorphisms in genes encoding two important negative regulators of the alternative complement pathway, complement factor H (CFH) and complement factor I (CFI), are associated with the risk for Age-Related Macular Degeneration (AMD), a leading cause of vision impairment in the ageing population. In this review, we will discuss the genetic basis of AMD and the potential impact of complement de-regulation on disease pathogenesis. Finally, we will highlight recent therapeutic approaches aimed at controlling complement activation in patients with AMD. PMID:26742632

  7. Present and Possible Therapies for Age-Related Macular Degeneration

    PubMed Central

    Kamal, Ahmed

    2014-01-01

    Age-related macular degeneration (AMD) is the most common cause of blindness in the elderly population worldwide and is defined as a chronic, progressive disorder characterized by changes occurring within the macula reflective of the ageing process. At present, the prevalence of AMD is currently rising and is estimated to increase by a third by 2020. Although our understanding of the several components underpinning the pathogenesis of this condition has increased significantly, the treatment options for this condition remain substantially limited. In this review, we outline the existing arsenal of therapies available for AMD and discuss the additional role of further novel therapies currently under investigation for this debilitating disease. PMID:25097787

  8. [Glaucoma and age-related macular degeneration intricacy].

    PubMed

    Valtot, F

    2008-07-01

    Age-related macular degeneration (AMD) is the leading cause of legal blindness among the elderly in Western nations. Age is also a well-known and well-evidenced risk factor for glaucoma. With increasing longevity and the rising prevalence of older people around the world, more and more patients will have glaucoma and AMD. Clinical evaluation of these patients still poses problems for clinicians. It is very important to order the right tests at the right time to distinguish glaucomatous defects from those caused by retinal lesions, because appropriate therapy has a beneficial effect on slowing or halting damage. PMID:18957915

  9. Copy number variations related to reproduction traits in Holstein cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Daughter pregnancy rate (DPR) is one of important reproduction traits that affect overall profitability in dairy industry. However, historical selection for production and conformation rather than reproduction has resulted in a decline in cow fertility. Genomic structural variation including copy nu...

  10. Age-Related Differences and Heterogeneity in Executive Functions: Analysis of NAB Executive Functions Module Scores.

    PubMed

    Buczylowska, Dorota; Petermann, Franz

    2016-05-01

    Normative data from the German adaptation of the Neuropsychological Assessment Battery were used to examine age-related differences in 6 executive function tasks. A multivariate analysis of variance was employed to investigate the differences in performance in 484 participants aged 18-99 years. The coefficient of variation was calculated to compare the heterogeneity of scores between 10 age groups. Analyses showed an increase in the dispersion of scores with age, varying from 7% to 289%, in all subtests. Furthermore, age-dependent heterogeneity appeared to be associated with age-dependent decline because the subtests with the greatest increase in dispersion (i.e., Mazes, Planning, and Categories) also exhibited the greatest decrease in mean scores. In contrast, scores for the subtests Letter Fluency, Word Generation, and Judgment had the lowest increase in dispersion with the lowest decrease in mean scores. Consequently, the results presented here show a pattern of age-related differences in executive functioning that is consistent with the concept of crystallized and fluid intelligence. PMID:26953227

  11. Innate immunity and inflammation in ageing: a key for understanding age-related diseases

    PubMed Central

    Licastro, Federico; Candore, Giuseppina; Lio, Domenico; Porcellini, Elisa; Colonna-Romano, Giuseppina; Franceschi, Claudio; Caruso, Calogero

    2005-01-01

    The process of maintaining life for the individual is a constant struggle to preserve his/her integrity. This can come at a price when immunity is involved, namely systemic inflammation. Inflammation is not per se a negative phenomenon: it is the response of the immune system to the invasion of viruses or bacteria and other pathogens. During evolution the human organism was set to live 40 or 50 years; today, however, the immune system must remain active for much a longer time. This very long activity leads to a chronic inflammation that slowly but inexorably damages one or several organs: this is a typical phenomenon linked to ageing and it is considered the major risk factor for age-related chronic diseases. Alzheimer's disease, atherosclerosis, diabetes and even sarcopenia and cancer, just to mention a few – have an important inflammatory component, though disease progression seems also dependent on the genetic background of individuals. Emerging evidence suggests that pro-inflammatory genotypes are related to unsuccessful ageing, and, reciprocally, controlling inflammatory status may allow a better chance of successful ageing. In other words, age-related diseases are "the price we pay" for a life-long active immune system: this system has also the potential to harm us later, as its fine tuning becomes compromised. Our immune system has evolved to control pathogens, so pro-inflammatory responses are likely to be evolutionarily programmed to resist fatal infections with pathogens aggressively. Thus, inflammatory genotypes are an important and necessary part of the normal host responses to pathogens in early life, but the overproduction of inflammatory molecules might also cause immune-related inflammatory diseases and eventually death later. Therefore, low responder genotypes involved in regulation of innate defence mechanisms, might better control inflammatory responses and age-related disease development, resulting in an increased chance of long life survival

  12. Cfh genotype interacts with dietary glycemic index to modulate age-related macular degeneration-like features in mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Age-related macular degeneration (AMD) is a leading cause of visual impairment worldwide. Genetics and diet contribute to the relative risk for developing AMD, but their interactions are poorly understood. Genetic variations in Complement Factor H (CFH), and dietary glycemic index (GI) are major ris...

  13. 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

  14. Aging Chart: a community resource for rapid exploratory pathway analysis of age-related processes

    PubMed Central

    Moskalev, Alexey; Zhikrivetskaya, Svetlana; Shaposhnikov, Mikhail; Dobrovolskaya, Evgenia; Gurinovich, Roman; Kuryan, Oleg; Pashuk, Aleksandr; Jellen, Leslie C.; Aliper, Alex; Peregudov, Alex; Zhavoronkov, Alex

    2016-01-01

    Aging research is a multi-disciplinary field encompassing knowledge from many areas of basic, applied and clinical research. Age-related processes occur on molecular, cellular, tissue, organ, system, organismal and even psychological levels, trigger the onset of multiple debilitating diseases and lead to a loss of function, and there is a need for a unified knowledge repository designed to track, analyze and visualize the cause and effect relationships and interactions between the many elements and processes on all levels. Aging Chart (http://agingchart.org/) is a new, community-curated collection of aging pathways and knowledge that provides a platform for rapid exploratory analysis. Building on an initial content base constructed by a team of experts from peer-reviewed literature, users can integrate new data into biological pathway diagrams for a visible, intuitive, top-down framework of aging processes that fosters knowledge-building and collaboration. As the body of knowledge in aging research is rapidly increasing, an open visual encyclopedia of aging processes will be useful to both the new entrants and experts in the field. PMID:26602690

  15. Aging Chart: a community resource for rapid exploratory pathway analysis of age-related processes.

    PubMed

    Moskalev, Alexey; Zhikrivetskaya, Svetlana; Shaposhnikov, Mikhail; Dobrovolskaya, Evgenia; Gurinovich, Roman; Kuryan, Oleg; Pashuk, Aleksandr; Jellen, Leslie C; Aliper, Alex; Peregudov, Alex; Zhavoronkov, Alex

    2016-01-01

    Aging research is a multi-disciplinary field encompassing knowledge from many areas of basic, applied and clinical research. Age-related processes occur on molecular, cellular, tissue, organ, system, organismal and even psychological levels, trigger the onset of multiple debilitating diseases and lead to a loss of function, and there is a need for a unified knowledge repository designed to track, analyze and visualize the cause and effect relationships and interactions between the many elements and processes on all levels. Aging Chart (http://agingchart.org/) is a new, community-curated collection of aging pathways and knowledge that provides a platform for rapid exploratory analysis. Building on an initial content base constructed by a team of experts from peer-reviewed literature, users can integrate new data into biological pathway diagrams for a visible, intuitive, top-down framework of aging processes that fosters knowledge-building and collaboration. As the body of knowledge in aging research is rapidly increasing, an open visual encyclopedia of aging processes will be useful to both the new entrants and experts in the field. PMID:26602690

  16. Age-related decline in global form suppression.

    PubMed

    Wiegand, Iris; Finke, Kathrin; Töllner, Thomas; Starman, Kornelija; Müller, Hermann J; Conci, Markus

    2015-12-01

    Visual selection of illusory 'Kanizsa' figures, an assembly of local elements that induce the percept of a whole object, is facilitated relative to configurations composed of the same local elements that do not induce a global form--an instance of 'global precedence' in visual processing. Selective attention, i.e., the ability to focus on relevant and ignore irrelevant information, declines with increasing age; however, how this deficit affects selection of global vs. local configurations remains unknown. On this background, the present study examined for age-related differences in a global-local task requiring selection of either a 'global' Kanizsa- or a 'local' non-Kanizsa configuration (in the presence of the respectively other configuration) by analyzing event-related lateralizations (ERLs). Behaviorally, older participants showed a more pronounced global-precedence effect. Electrophysiologically, this effect was accompanied by an early (150-225 ms) 'positivity posterior contralateral' (PPC), which was elicited for older, but not younger, participants, when the target was a non-Kanizsa configuration and the Kanizsa figure a distractor (rather than vice versa). In addition, timing differences in the subsequent (250-500 ms) posterior contralateral negativity (PCN) indicated that attentional resources were allocated faster to Kanizsa, as compared to non-Kanizsa, targets in both age groups, while the allocation of spatial attention seemed to be generally delayed in older relative to younger age. Our results suggest that the enhanced global-local asymmetry in the older age group originated from less effective suppression of global distracter forms on early processing stages--indicative of older observers having difficulties with disengaging from a global default selection mode and switching to the required local state of attentional resolution. PMID:26498865

  17. NADPH oxidases: key modulators in aging and age-related cardiovascular diseases?

    PubMed Central

    Sahoo, Sanghamitra; Meijles, Daniel N.; Pagano, Patrick J.

    2016-01-01

    Reactive oxygen species (ROS) and oxidative stress have long been linked to aging and diseases prominent in the elderly such as hypertension, atherosclerosis, diabetes and atrial fibrillation (AF). NADPH oxidases (Nox) are a major source of ROS in the vasculature and are key players in mediating redox signalling under physiological and pathophysiological conditions. In this review, we focus on the Nox-mediated ROS signalling pathways involved in the regulation of ‘longevity genes’ and recapitulate their role in age-associated vascular changes and in the development of age-related cardiovascular diseases (CVDs). This review is predicated on burgeoning knowledge that Nox-derived ROS propagate tightly regulated yet varied signalling pathways, which, at the cellular level, may lead to diminished repair, the aging process and predisposition to CVDs. In addition, we briefly describe emerging Nox therapies and their potential in improving the health of the elderly population. PMID:26814203

  18. Spatio-temporal variations in age structures of a partially re-established population of northern river otters (Lontra canadensis)

    USGS Publications Warehouse

    Barrett, Dominic A.; Leslie, David M., Jr.

    2012-01-01

    Examination of age structures and sex ratios is useful in the management of northern river otters (Lontra canadensis) and other furbearers. Reintroductions and subsequent recolonizations of river otters have been well documented, but changes in demographics between expanding and established populations have not been observed. As a result of reintroduction efforts, immigration from Arkansas and northeastern Texas, and other efforts, river otters have become partially reestablished throughout eastern and central Oklahoma. Our objective was to examine age structures of river otters in Oklahoma and identify trends that relate to space (watersheds, county) and time (USDA Animal and Plant Health Inspection Service county trapping records). We predicted that river otters in western areas of the state were younger than river otters occurring farther east. From 2005–2007, we obtained salvaged river otter carcasses from federal and state agencies, and we live-captured other river otters using leg hold traps. Seventy-two river otters were sampled. Overall, sex ratios were skewed toward females (1F∶0.8M), but they did not differ among spatiotemporal scales examined. Teeth were removed from salvaged and live-captured river otters (n  =  63) for aging. One-year old river otters represented the largest age class (30.2%). Proportion of juveniles (<1 y old) in Oklahoma (19.0%) was less than other states. Mean age of river otters decreased from east-to-west in the Arkansas River and its tributaries. Mean age of river otters differed between the Canadian River Watershed (0.8 y) and the Arkansas River Watershed (2.9 y) and the Canadian River Watershed and the Red River Watershed (2.4 y). Proportion of juveniles did not differ among spatiotemporal scales examined. Similar to age structure variations in other mammalian carnivores, colonizing or growing western populations of river otters in Oklahoma contained younger ages than more established eastern populations.

  19. Dietary compound score and risk of age-related macular degeneration in the Age-Related Eye Disease Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Purpose: Because foods provide many nutrients, which may interact with each other to modify risk for multifactorial diseases such as age-related macular degeneration (AMD), we sought to develop a composite scoring system to summarize the combined effect of multiple dietary nutrients on AMD risk. Th...

  20. Alarm signals of the great gerbil: Acoustic variation by predator context, sex, age, individual, and family group

    NASA Astrophysics Data System (ADS)

    Randall, Jan A.; McCowan, Brenda; Collins, Kellie C.; Hooper, Stacie L.; Rogovin, Konstantin

    2005-10-01

    The great gerbil, Rhombomys opinus, is a highly social rodent that usually lives in family groups consisting of related females, their offspring, and an adult male. The gerbils emit alarm vocalizations in the presence of diverse predators with different hunting tactics. Alarm calls were recorded in response to three predators, a monitor lizard, hunting dog, and human, to determine whether the most common call type, the rhythmic call, is functionally referential with regard to type of predator. Results show variation in the alarm calls of both adults and subadults with the type of predator. Discriminant function analysis classified an average of 70% of calls to predator type. Call variation, however, was not limited to the predator context, because signal structure also differed by sex, age, individual callers, and family groups. These variations illustrate the flexibility of the rhythmic alarm call of the great gerbil and how it might have multiple functions and communicate in multiple contexts. Three alarm calls, variation in the rhythmic call, and vibrational signals generated from foot-drumming provide the gerbils with a varied and multi-channel acoustic repertoire.

  1. Heterogeneity of Relational Backgrounds is Associated With Variation in Non-Suicidal Self-Injurious Behavior.

    PubMed

    Martin, Jodi; Bureau, Jean-François; Yurkowski, Kim; Lafontaine, Marie-France; Cloutier, Paula

    2016-04-01

    Non-suicidal self-injury (NSSI) is a self-destructive behavior of common prevalence in adolescence and young adulthood. Engagement in NSSI has been consistently linked in the literature with perceptions of one's parent-child relationships as negative or invalidating. However, the potential for multiple combinations of such relational characteristics to be associated with varying cognitive and behavioral manifestations of NSSI remains uninvestigated. In the current study, a person-centered approach to studying perceived parent-child relationship quality and NSSI was adopted; functions and behavioral severity of NSSI were then compared across the different relational profiles created. A latent profile analysis in a sample of 264 self-injuring university students (205 females; m(age) = 19.37 years, sd = 1.50) revealed four distinct profiles, two characterized by negative parent-child perceptions and two by positive parent-child perceptions. The perceived relational dimensions of these profiles were unique compared to a parallel group of 264 non-self-injurers (207 females; m(age) = 19.27 years, sd = 1.33). Participants reporting negative parent-child relationships endorsed more severe NSSI, and engaged in NSSI to regulate aggressive emotions. In contrast, individuals reporting positive parent-child relationships engaged in less extreme manifestations of NSSI overall, suggesting lower psychological deficits. Findings suggest that, although not all self-injurers perceive their relationships with parents negatively, variation in the perception of relational quality is implicated in behavioral and cognitive variation in NSSI engagement. PMID:26133094

  2. Relation of smoking to the incidence of age-related maculopathy. The Beaver Dam Eye Study.

    PubMed

    Klein, R; Klein, B E; Moss, S E

    1998-01-15

    To date, a number of reports have been published on the relation of cigarette smoking to age-related maculopathy, an important cause of blindness in the United States. However, few studies have examined the relation between smoking and the incidence of age-related maculopathy. In this report, the authors examine this association in persons aged 43-86 years (n = 3,583) at baseline who were participants in the baseline examination and 5-year follow-up of the Beaver Dam Eye Study, Beaver Dam, Wisconsin (1988-1990 and 1993-1995). Exposure data on cigarette smoking were obtained from questions about present and past smoking, duration of smoking, and the number of cigarettes smoked per day. Age-related maculopathy status was determined by grading stereoscopic color fundus photographs using the Wisconsin Age-related Maculopathy Grading System. After controlling for age, sex, vitamin supplement use, and beer consumption, men who smoked greater amounts of cigarettes were more likely to develop early age-related maculopathy (odds ratio (OR) per 10 pack-years smoked = 1.06, 95% confidence interval (CI) 1.00-1.13, p = 0.06) than men who had smoked less. This association was not observed in women. Men (OR = 3.21, 95% CI 1.09-9.45) and women (OR = 2.20, 95% CI 1.04-4.66) who were current smokers at the time of the baseline examination had significantly higher odds of developing large drusen (> or = 250 microns in diameter) after 5 years than those who had never smoked or who quit before the baseline study. Current or past history of cigarette smoking was not related to the incidence of retinal pigment epithelial depigmentation. The authors conclude that smoking appears to be related to the incidence of some lesions associated with early age-related maculopathy. PMID:9456998

  3. Examining genotypic variation in autism spectrum disorder and its relationship to parental age and phenotype

    PubMed Central

    Geier, David A; Kern, Janet K; Sykes, Lisa K; Geier, Mark R

    2016-01-01

    Background Previous studies on genetic testing of chromosomal abnormalities in individuals diagnosed with autism spectrum disorder (ASD) found that ~80% have negative genetic test results (NGTRs) and ~20% have positive genetic test results (PGTRs), of which ~7% were probable de novo mutations (PDNMs). Research suggests that parental age is a risk factor for an ASD diagnosis. This study examined genotypic variation in ASD and its relationship to parental age and phenotype. Methods Phenotype was derived from detailed clinical information, and genotype was derived from high-resolution blood chromosome and blood whole-genome copy number variant genetic testing on a consecutive cohort (born: 1983–2009) of subjects diagnosed with ASD (N=218). Results Among the subjects examined, 80.3% had NGTRs and 19.7% had PGTRs, of which 6.9% had PDNMs. NGTR subjects were born more recently (the risk of PDNMs decreasing by 12% per more recent birth year) and tended to have an increased male–female ratio compared to PDNM subjects. PDNM subjects had significantly increased mean parental age and paternal age at subject’s birth (the risk of a PDNM increasing by 7%–8% per year of parental or paternal age) compared to NGTR subjects. PGTR and NGTR subjects showed significant improvements in speech/language/communication with increasing age. PGTR subjects showed significant improvements in sociability, a core feature of an ASD diagnosis, with increasing age, whereas NGTR subjects showed significant worsening in sociability with increasing age. Conclusion This study helps to elucidate different phenotypic ASD subtypes and may even indicate the need for differential diagnostic classifications. PMID:27555794

  4. Treatment of neovascular age-related macular degeneration: Current therapies

    PubMed Central

    Augustin, Albert J; Scholl, Stefan; Kirchhof, Janna

    2009-01-01

    Choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD) is now the leading cause of blindness and severe vision loss among people over the age of 40 in the Western world. Its prevalence is certain to increase substantially as the population ages. Treatments currently available for the disease include laser photocoagulation, verteporfin photodynamic therapy, and intravitreal injections of corticosteroids and anti-angiogenic agents. Many studies have reported the benefits of each of these treatments, although none is without its risks. No intervention actually cures AMD, nor the neovascularization associated with it. However, its symptoms are treated with varying degrees of success. Some treatments stabilize or arrest the progress of the disease. Others have been shown to reverse some of the damage that has already been done. These treatments can even lead to visual improvement. This paper will review the major classes of drugs and therapies designed to treat this condition. PMID:19668562

  5. Age-Related Macular Degeneration: Insights into Inflammatory Genes

    PubMed Central

    Ragazzo, Michele; Missiroli, Filippo; Borgiani, Paola; Angelucci, Francesco; Marsella, Luigi Tonino; Cusumano, Andrea; Novelli, Giuseppe; Ricci, Federico; Giardina, Emiliano

    2014-01-01

    Age-related macular degeneration (AMD) is a progressive neurodegenerative disease that affects approximately 8.7% of elderly people worldwide (>55 years old). AMD is characterized by a multifactorial aetiology that involves several genetic and environmental risk factors (genes, ageing, smoking, family history, dietary habits, oxidative stress, and hypertension). In particular, ageing and cigarette smoking (including oxidative compounds and reactive oxygen species) have been shown to significantly increase susceptibility to the disease. Furthermore, different genes (CFH, CFI, C2, C3, IL-6, IL-8, and ARMS2) that play a crucial role in the inflammatory pathway have been associated with AMD risk. Several genetic and molecular studies have indicated the participation of inflammatory molecules (cytokines and chemokines), immune cells (macrophages), and complement proteins in the development and progression of the disease. Taking into consideration the genetic and molecular background, this review highlights the genetic role of inflammatory genes involved in AMD pathogenesis and progression. PMID:25478207

  6. Spatial variation in gender-biased parasitism: host-related, parasite-related and environment-related effects.

    PubMed

    Krasnov, Boris R; Matthee, Sonja

    2010-09-01

    The gender-biased pattern of parasite infestation has been shown to be a complicated phenomenon that cannot be explained by a single mechanism but rather involves several different mechanisms. We asked what are the factors that affect the manifestation and extent of gender-biased parasitism and studied the relationship between parasite-related (mean abundance, mean species richness and total species richness of all parasites), host-related (rodent density and proportion of reproductive males and females both separately and together) and environment-related (mean daily maximal and minimal temperatures, rainfall and relative humidity) factors and the magnitude of gender-biased infestation of a South African rodent Rhabdomys pumilio by ixodid ticks, gamasid mites, lice and fleas. We found that spatial variation in gender differences in parasite infestation was affected by parasite-, host- and environment-related factors, although the set of factors affecting gender differences in infestation differed among higher taxa of ectoparasites. Gender differences in infestation by fleas and lice were affected mainly by parasite-related factors, whereas gender differences in infestation by ticks and, in part, by mites were affected mainly by host-related and environmental factors. In addition, spatial variation in most measures of gender difference in mite infestation remained unexplained. PMID:20550754

  7. Age-Related Tissue Stiffening: Cause and Effect

    PubMed Central

    Sherratt, Michael J.

    2013-01-01

    Significance Tissue elasticity is severely compromised in aging skin, lungs, and blood vessels. In the vascular and pulmonary systems, respectively, loss of mechanical function is linked to hypertension, which in turn is a risk factor for heart and renal failure, stroke, and aortic aneurysms, and to an increased risk of mortality as a result of acute lung infections. Recent Advances Although cellular mechanisms were thought to play an important role in mediating tissue aging, the reason for the apparent sensitivity of elastic fibers to age-related degradation remained unclear. We have recently demonstrated that compared with type I collagen, a key component of the elastic fiber system, the cysteine-rich fibrillin microfibril is highly susceptible to direct UV exposure in a cell-free environment. We hypothesized therefore that, as a consequence of both their remarkable longevity and cysteine-rich composition, many elastic fiber-associated components will be susceptible to the accumulation of damage by both direct UV radiation and reactive oxygen species-mediated oxidation. Critical Issues Although elastic fiber remodeling is a common feature of aging dynamic tissues, the inaccessibility of most human tissues has hampered attempts to define the molecular causes. Clinical Care Relevance Although, currently, the localized repair of damaged elastic fibers may be effected by the topical application of retinoids and some cosmetic products, future studies may extend the application of systemic transforming growth factor β antagonists, which can prevent cardiovascular remodeling in murine Marfan syndrome, to aging humans. Acellular mechanisms may be key mediators of elastic fiber remodeling and hence age-related tissue stiffening. PMID:24527318

  8. Age-related changes in serological susceptibility patterns to measles

    PubMed Central

    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

  9. Nitroxide pharmaceutical development for age-related degeneration and disease

    PubMed Central

    Zarling, Jacob A.; Brunt, Vienna E.; Vallerga, Anne K.; Li, Weixing; Tao, Albert; Zarling, David A.; Minson, Christopher T.

    2015-01-01

    Nitroxide small molecule agents are in development as preventative or therapeutic pharmaceutical drugs for age-related macular degeneration (AMD) and cardiovascular disease, which are two major diseases of aging. These aging diseases are associated with patient genetics, smoking, diet, oxidative stress, and chronic inflammation. Nitroxide drugs preventing aging-, smoking-, high sugar or high fat diet-, or radiation- and other environmental-induced pathophysiological conditions in aging disease are reviewed. Tempol (TP), Tempol Hydroxylamine (TP-H), and TP-H prodrug (OT-551) are evaluated in (1) non-smokers versus smokers with cutaneous microvascular dysfunction, rapidly reversed by cutaneous TP; (2) elderly cancer patients at risk for radiation-induced skin burns or hair loss, prevented by topical TP; and (3) elderly smoker or non-smoker AMD patients at risk for vision loss, prevented by daily eye drops of OT-551. The human data indicates safety and efficacy for these nitroxide drugs. Both TP and TP-H topically penetrate and function in skin or mucosa, protecting and treating radiation burns and hair loss or smoking-induced cutaneous vascular dysfunction. TP and TP-H do not penetrate the cornea, while OT-551 does effectively penetrate and travels to the back of the eye, preserving visual acuity and preserving normal and low light luminance in dry AMD smokers and non-smoker patients. Topical, oral, or injectable drug formulations are discussed. PMID:26594225

  10. Age-related thermal response: the cellular resilience of juveniles.

    PubMed

    Clark, M S; Thorne, M A S; Burns, G; Peck, L S

    2016-01-01

    Understanding species' responses to environmental challenges is key to predicting future biodiversity. However, there is currently little data on how developmental stages affect responses and also whether universal gene biomarkers to environmental stress can be identified both within and between species. Using the Antarctic clam, Laternula elliptica, as a model species, we examined both the tissue-specific and age-related (juvenile versus mature adult) gene expression response to acute non-lethal warming (12 h at 3 °C). In general, there was a relatively muted response to this sub-lethal thermal challenge when the expression profiles of treated animals, of either age, were compared with those of 0 °C controls, with none of the "classical" stress response genes up-regulated. The expression profiles were very variable between the tissues of all animals, irrespective of age with no single transcript emerging as a universal biomarker of thermal stress. However, when the expression profiles of treated animals of the different age groups were directly compared, a very different pattern emerged. The profiles of the younger animals showed significant up-regulation of chaperone and antioxidant transcripts when compared with those of the older animals. Thus, the younger animals showed evidence of a more robust cellular response to warming. These data substantiate previous physiological analyses showing a more resilient juvenile population. PMID:26364303

  11. Mechanism of Inflammation in Age-Related Macular Degeneration

    PubMed Central

    Parmeggiani, Francesco; Romano, Mario R.; Costagliola, Ciro; Semeraro, Francesco; Incorvaia, Carlo; D'Angelo, Sergio; Perri, Paolo; De Palma, Paolo; De Nadai, Katia; Sebastiani, Adolfo

    2012-01-01

    Age-related macular degeneration (AMD) is a multifactorial disease that represents the most common cause of irreversible visual impairment among people over the age of 50 in Europe, the United States, and Australia, accounting for up to 50% of all cases of central blindness. Risk factors of AMD are heterogeneous, mainly including increasing age and different genetic predispositions, together with several environmental/epigenetic factors, that is, cigarette smoking, dietary habits, and phototoxic exposure. In the aging retina, free radicals and oxidized lipoproteins are considered to be major causes of tissue stress resulting in local triggers for parainflammation, a chronic status which contributes to initiation and/or progression of many human neurodegenerative diseases such as AMD. Experimental and clinical evidences strongly indicate the pathogenetic role of immunologic processes in AMD occurrence, consisting of production of inflammatory related molecules, recruitment of macrophages, complement activation, microglial activation and accumulation within those structures that compose an essential area of the retina known as macula lutea. This paper reviews some attractive aspects of the literature about the mechanisms of inflammation in AMD, especially focusing on those findings or arguments more directly translatable to improve the clinical management of patients with AMD and to prevent the severe vision loss caused by this disease. PMID:23209345

  12. Variations of immune parameters in terrestrial isopods: a matter of gender, aging and Wolbachia.

    PubMed

    Sicard, Mathieu; Chevalier, Frédéric; De Vlechouver, Mickaël; Bouchon, Didier; Grève, Pierre; Braquart-Varnier, Christine

    2010-09-01

    Ecological factors modulate animal immunocompetence and potentially shape the evolution of their immune systems. Not only environmental parameters impact on immunocompetence: Aging is one major cause of variability of immunocompetence between individuals, and sex-specific levels of immunocompetence have also been frequently described. Moreover, a growing core of data put in light that vertically transmitted symbionts can dramatically modulate the immunocompetence of their hosts. In this study, we addressed the influence of gender, age and the feminising endosymbiont Wolbachia (wVulC) on variations in haemocyte density, total PO activity and bacterial load in the haemolymph of the terrestrial isopod Armadillidium vulgare. This host-symbiont system is of particular interest to address this question since: (1) wVulC was previously shown as immunosuppressive in middle-aged females and (2) wVulC influences sex determination. We show that age, gender and Wolbachia modulate together immune parameters in A. vulgare. However, wVulC, which interacts with aging, appears to be the prominent factor interfering with both PO activity and haemocyte density. This interference with immune parameters is not the only aspect of wVulC virulence on its host, as reproduction and survival are also altered. PMID:20676599

  13. Variations of immune parameters in terrestrial isopods: a matter of gender, aging and Wolbachia

    NASA Astrophysics Data System (ADS)

    Sicard, Mathieu; Chevalier, Frédéric; de Vlechouver, Mickaël; Bouchon, Didier; Grève, Pierre; Braquart-Varnier, Christine

    2010-09-01

    Ecological factors modulate animal immunocompetence and potentially shape the evolution of their immune systems. Not only environmental parameters impact on immunocompetence: Aging is one major cause of variability of immunocompetence between individuals, and sex-specific levels of immunocompetence have also been frequently described. Moreover, a growing core of data put in light that vertically transmitted symbionts can dramatically modulate the immunocompetence of their hosts. In this study, we addressed the influence of gender, age and the feminising endosymbiont Wolbachia ( wVulC) on variations in haemocyte density, total PO activity and bacterial load in the haemolymph of the terrestrial isopod Armadillidium vulgare. This host-symbiont system is of particular interest to address this question since: (1) wVulC was previously shown as immunosuppressive in middle-aged females and (2) wVulC influences sex determination. We show that age, gender and Wolbachia modulate together immune parameters in A. vulgare. However, wVulC, which interacts with aging, appears to be the prominent factor interfering with both PO activity and haemocyte density. This interference with immune parameters is not the only aspect of wVulC virulence on its host, as reproduction and survival are also altered.

  14. Touchscreen-Based Cognitive Tasks Reveal Age-Related Impairment in a Primate Aging Model, the Grey Mouse Lemur (Microcebus murinus)

    PubMed Central

    2014-01-01

    Mouse lemurs are suggested to represent promising novel non-human primate models for aging research. However, standardized and cross-taxa cognitive testing methods are still lacking. Touchscreen-based testing procedures have proven high stimulus control and reliability in humans and rodents. The aim of this study was to adapt these procedures to mouse lemurs, thereby exploring the effect of age. We measured appetitive learning and cognitive flexibility of two age groups by applying pairwise visual discrimination (PD) and reversal learning (PDR) tasks. On average, mouse lemurs needed 24 days of training before starting with the PD task. Individual performances in PD and PDR tasks correlate significantly, suggesting that individual learning performance is unrelated to the respective task. Compared to the young, aged mouse lemurs showed impairments in both PD and PDR tasks. They needed significantly more trials to reach the task criteria. A much higher inter-individual variation in old than in young adults was revealed. Furthermore, in the PDR task, we found a significantly higher perseverance in aged compared to young adults, indicating an age-related deficit in cognitive flexibility. This study presents the first touchscreen-based data on the cognitive skills and age-related dysfunction in mouse lemurs and provides a unique basis to study mechanisms of inter-individual variation. It furthermore opens exciting perspectives for comparative approaches in aging, personality, and evolutionary research. PMID:25299046

  15. The emerging role of Notch pathway in ageing: Focus on the related mechanisms in age-related diseases.

    PubMed

    Balistreri, Carmela Rita; Madonna, Rosalinda; Melino, Gerry; Caruso, Calogero

    2016-08-01

    Notch signaling is an evolutionarily conserved pathway, which is fundamental for the development of all tissues, organs and systems of human body. Recently, a considerable and still growing number of studies have highlighted the contribution of Notch signaling in various pathological processes of the adult life, such as age-related diseases. In particular, the Notch pathway has emerged as major player in the maintenance of tissue specific homeostasis, through the control of proliferation, migration, phenotypes and functions of tissue cells, as well as in the cross-talk between inflammatory cells and the innate immune system, and in onset of inflammatory age-related diseases. However, until now there is a confounding evidence about the related mechanisms. Here, we discuss mechanisms through which Notch signaling acts in a very complex network of pathways, where it seems to have the crucial role of hub. Thus, we stress the possibility to use Notch pathway, the related molecules and pathways constituting this network, both as innovative (predictive, diagnostic and prognostic) biomarkers and targets for personalised treatments for age-related diseases. PMID:27328278

  16. 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

  17. Idiom understanding in adulthood: examining age-related differences.

    PubMed

    Hung, Pei-Fang; Nippold, Marilyn A

    2014-03-01

    Idioms are figurative expressions such as hold your horses, kick the bucket, and lend me a hand, which commonly occur in everyday spoken and written language. Hence, the understanding of these expressions is essential for daily communication. In this study, we examined idiom understanding in healthy adults in their 20s, 40s, 60s and 80s (n=30 per group) to determine if performance would show an age-related decline. Participants judged their own familiarity with a set of 20 idioms, explained the meaning of each, described a situation in which the idiom could be used, and selected the appropriate interpretation from a set of choices. There was no evidence of an age-related decline on any tasks. Rather, the 60s group reported greater familiarity and offered better explanations than did the 20s group. Moreover, greater familiarity with idioms was associated with better understanding in adults. PMID:24405225

  18. Calorie Restriction Alleviates Age-Related Decrease in Neural Progenitor Cell Division in the Aging Brain

    PubMed Central

    Park, June-Hee; Glass, Zachary; Sayed, Kasim; Michurina, Tatyana V.; Lazutkin, Alexander; Mineyeva, Olga; Velmeshev, Dmitry; Ward, Walter F.; Richardson, Arlan; Enikolopov, Grigori

    2013-01-01

    Production of new neurons from stem cells is important for cognitive function, and the reduction of neurogenesis in the aging brain may contribute to the accumulation of age-related cognitive deficits. Restriction of calorie intake and prolonged treatment with rapamycin have been shown to extend the lifespan of animals and delay the onset of age-related decline in tissue and organ function. Using a reporter line in which neural stem and progenitor cells are marked by the expression of GFP, we examined the effect of prolonged exposure to calorie restriction (CR) or rapamycin on hippocampal neural stem and progenitor cell proliferation in aging mice. We show that CR increases the number of dividing cells in the dentate gyrus (DG) of female mice. The majority of these cells corresponded to Nestin-GFP-expressing neural stem or progenitor cells; however, this increased proliferative activity of stem and progenitor cells did not result in a significant increase in the number of doublecortin-positive newborn neurons. Our results suggest that restricted calorie intake may increase the number of divisions that neural stem and progenitor cells undergo in the aging brain of females. PMID:23773068

  19. Age-Related Hyperkyphosis: Its Causes, Consequences, and Management

    PubMed Central

    Katzman, Wendy B.; Wanek, Linda; Shepherd, John A.; Sellmeyer, Deborah E.

    2010-01-01

    Age-related postural hyperkyphosis is an exaggerated anterior curvature of the thoracic spine, sometimes referred to as Dowager’s hump or gibbous deformity. This condition impairs mobility,2,31 and increases the risk of falls33 and fractures.26 The natural history of hyperkyphosis is not firmly established. Hyperkyphosis may develop from either muscle weakness and degenerative disc disease, leading to vertebral fractures and worsening hyperkyphosis, or from initial vertebral fractures that precipitate its development. PMID:20511692

  20. Smoking and Age-Related Macular Degeneration: Review and Update

    PubMed Central

    Velilla, Sara; García-Medina, José Javier; García-Layana, Alfredo; Pons-Vázquez, Sheila; Pinazo-Durán, M. Dolores; Gómez-Ulla, Francisco; Arévalo, J. Fernando; Díaz-Llopis, Manuel; Gallego-Pinazo, Roberto

    2013-01-01

    Age-related macular degeneration (AMD) is one of the main socioeconomical health issues worldwide. AMD has a multifactorial etiology with a variety of risk factors. Smoking is the most important modifiable risk factor for AMD development and progression. The present review summarizes the epidemiological studies evaluating the association between smoking and AMD, the mechanisms through which smoking induces damage to the chorioretinal tissues, and the relevance of advising patients to quit smoking for their visual health. PMID:24368940

  1. Sex-dependent dominance at a single locus maintains variation in age at maturity in salmon.

    PubMed

    Barson, Nicola J; Aykanat, Tutku; Hindar, Kjetil; Baranski, Matthew; Bolstad, Geir H; Fiske, Peder; Jacq, Céleste; Jensen, Arne J; Johnston, Susan E; Karlsson, Sten; Kent, Matthew; Moen, Thomas; Niemelä, Eero; Nome, Torfinn; Næsje, Tor F; Orell, Panu; Romakkaniemi, Atso; Sægrov, Harald; Urdal, Kurt; Erkinaro, Jaakko; Lien, Sigbjørn; Primmer, Craig R

    2015-12-17

    Males and females share many traits that have a common genetic basis; however, selection on these traits often differs between the sexes, leading to sexual conflict. Under such sexual antagonism, theory predicts the evolution of genetic architectures that resolve this sexual conflict. Yet, despite intense theoretical and empirical interest, the specific loci underlying sexually antagonistic phenotypes have rarely been identified, limiting our understanding of how sexual conflict impacts genome evolution and the maintenance of genetic diversity. Here we identify a large effect locus controlling age at maturity in Atlantic salmon (Salmo salar), an important fitness trait in which selection favours earlier maturation in males than females, and show it is a clear example of sex-dependent dominance that reduces intralocus sexual conflict and maintains adaptive variation in wild populations. Using high-density single nucleotide polymorphism data across 57 wild populations and whole genome re-sequencing, we find that the vestigial-like family member 3 gene (VGLL3) exhibits sex-dependent dominance in salmon, promoting earlier and later maturation in males and females, respectively. VGLL3, an adiposity regulator associated with size and age at maturity in humans, explained 39% of phenotypic variation, an unexpectedly large proportion for what is usually considered a highly polygenic trait. Such large effects are predicted under balancing selection from either sexually antagonistic or spatially varying selection. Our results provide the first empirical example of dominance reversal allowing greater optimization of phenotypes within each sex, contributing to the resolution of sexual conflict in a major and widespread evolutionary trade-off between age and size at maturity. They also provide key empirical evidence for how variation in reproductive strategies can be maintained over large geographical scales. We anticipate these findings will have a substantial impact on

  2. Variation in orbitofrontal cortex volume: relation to sex, emotion regulation and affect

    PubMed Central

    Welborn, B. Locke; Papademetris, Xenophon; Reis, Deidre L.; Rajeevan, Nallakkandi; Bloise, Suzanne M.

    2009-01-01

    Sex differences in brain structure have been examined extensively but are not completely understood, especially in relation to possible functional correlates. Our two aims in this study were to investigate sex differences in brain structure, and to investigate a possible relation between orbitofrontal cortex subregions and affective individual differences. We used tensor-based morphometry to estimate local brain volume from MPRAGE images in 117 healthy right-handed adults (58 female), age 18–40 years. We entered estimates of local brain volume as the dependent variable in a GLM, controlling for age, intelligence and whole-brain volume. Men had larger left planum temporale. Women had larger ventromedial prefrontal cortex (vmPFC), right lateral orbitofrontal (rlOFC), cerebellum, and bilateral basal ganglia and nearby white matter. vmPFC but not rlOFC volume covaried with self-reported emotion regulation strategies (reappraisal, suppression), expressivity of positive emotions (but not of negative), strength of emotional impulses, and cognitive but not somatic anxiety. vmPFC volume statistically mediated sex differences in emotion suppression. The results confirm prior reports of sex differences in orbitofrontal cortex structure, and are the first to show that normal variation in vmPFC volume is systematically related to emotion regulation and affective individual differences. PMID:20019072

  3. Cumulative Lead Exposure and Age-related Hearing Loss: The VA Normative Aging Study

    PubMed Central

    Park, Sung Kyun; Elmarsafawy, Sahar; Mukherjee, Bhramar; Spiro, Avron; Vokonas, Pantel S.; Nie, Huiling; Weisskopf, Marc G.; Schwartz, Joel; Hu, Howard

    2010-01-01

    Although lead has been associated with hearing loss in occupational settings and in children, little epidemiologic research has been conducted on the impact of cumulative lead exposure on age-related hearing loss in the general population. We determined whether bone lead levels, a marker of cumulative lead exposure, are associated with decreased hearing ability in 448 men from the Normative Aging Study, seen between 1962 and 1996 (2,264 total observations). Air conduction hearing thresholds were measured at 0.25 to 8 kHz and pure tone averages (PTA) (mean of 0.5, 1, 2 and 4 kHz) were computed. Tibia and patella lead levels were measured using K x-ray fluorescence between 1991 and 1996. In cross-sectional analyses, after adjusting for potential confounders including occupational noise, patella lead levels were significantly associated with poorer hearing thresholds at 2, 3, 4, 6 and 8 kHz and PTA. The odds of hearing loss significantly increased with patella lead levels. We also found significant positive associations between tibia lead and the rate change in hearing thresholds at 1, 2, and 8 kHz and PTA in longitudinal analyses. Our results suggest that chronic low-level lead exposure may be an important risk factor for age-related hearing loss and reduction of lead exposure could help prevent or delay development of age-related hearing loss. PMID:20638461

  4. [Diagnostic Criteria for Atrophic Age-related Macular Degeneration].

    PubMed

    Takahashi, Kanji; Shiraga, Fumio; Ishida, Susumu; Kamei, Motohiro; Yanagi, Yasuo; Yoshimura, Nagahisa

    2015-10-01

    Diagnostic criteria for dry age-related macular degeneration is described. Criteria include visual acuity, fundscopic findings, diagnostic image findings, exclusion criteria and classification of severity grades. Essential findings to make diagnosis as "geographic atrophy" are, 1) at least 250 μm in diameter, 2) round/oval/cluster-like or geographic in shape, 3) sharp delineation, 4) hypopigmentation or depigmentation in retinal pigment epithelium, 5) choroidal vessels are more visible than in surrounding area. Severity grades were classified as mild, medium and severe by relation of geographic atrophy to the fovea and attendant findings. PMID:26571627

  5. Age-related mate choice in the wandering albatross.

    PubMed

    Jouventin; Lequette; Dobson

    1999-05-01

    We studied mate choice in the wandering albatross, Diomedea exulans, using data from 32 years of banding returns in the population of the Crozet Islands. We studied mating choices in a single year, when the Crozet Islands population was male biased (8:5, males:females). Thus, we expected that females might show great flexibility of choice of partners. Because age and experience might influence mate choice, we tested the expectation that females would choose the oldest and most experienced males for pair bonding. Pair bonds usually last until one member of the pair dies (0.3% of the birds 'divorce'), so mate choice should be especially important. We found that the ages of males and females in both displaying and bonded (breeding) pairs were significantly correlated. These age-associated pairings were not a passive phenomenon, but appeared to be due to an active process of selection of mates of similar age. First-time breeders sought mates of similar age, but preferred those with the most experience. Remating, experienced birds whose mates had died did not pair with individuals of significantly similar age, but predominantly paired with other widowed birds that, on average, were also relatively old. Mate fidelity in wandering albatrosses may be due to the cost of finding and bonding with a new mate. Pair bonds, and thus breeding, took an average of 3.2 and 2.3 years to establish, for males and females, respectively. Thus, remating exerts a potential average reproductive cost of about 15% of lifetime reproductive success. Copyright 1999 The Association for the Study of Animal Behaviour. PMID:10328796

  6. 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.

  7. Influence of Age-Related Versus Non-Age-Related Renal Dysfunctionon Survival in Patients with Left Ventricular Dysfunction

    PubMed Central

    Testani, Jeffrey M.; Brisco, Meredith A.; Han, Gang; Laur, Olga; Kula, Alexander J.; Cheng, Susan J.; Tang, W. H. Wilson; Parikh, Chirag R.

    2013-01-01

    Normal aging results in a predictable decline in glomerular filtration rate (GFR) and low GFR is associated with worsened survival. If this survival disadvantage is directly caused by the low GFR, as opposed to the disease causing the low GFR, the risk should be similar regardless of the underlying mechanism. Our objective was to determine if age related declines in estimated GFR (eGFR) carry the same prognostic importance as disease attributable losses in patients with ventricular dysfunction. We analyzed the Studies Of Left Ventricular Dysfunction (SOLVD) limited data set (n=6337). The primary analysis focused on determining if the eGFR mortality relationship differed by the extent the eGFR was consistent with normal ageing. Mean eGFR was 65.7 ± 19.0ml/min/1.73m2. Across the range of age in the population (27 to 80 years), baseline eGFR decreased by 0.67 ml/min/1.73m2 per year (95% CI 0.63 to 0.71). The risk of death associated with eGFR was strongly modified by the degree to which the low eGFR could be explained by aging (p interaction <0.0001). For example, in a model incorporating the interaction, uncorrected eGFR was no longer significantly related to mortality (adjusted HR=1.0 per 10 ml/min/1.73m2, 95% CI 0.97–1.1, p=0.53) whereas a disease attributable decrease in eGFR above the median carried significant risk (adjusted HR=2.8, 95% CI 1.6–4.7, p<0.001). In conclusion, in the setting of LV dysfunction, renal dysfunction attributable to normal aging had a limited risk for mortality, suggesting that the mechanism underlying renal dysfunction is critical in determining prognosis. PMID:24216124

  8. Variations in Dream Recall Frequency and Dream Theme Diversity by Age and Sex

    PubMed Central

    Nielsen, Tore

    2012-01-01

    We assessed dream recall frequency (DRF) and dream theme diversity (DTD) with an internet questionnaire among a cohort of 28,888 male and female participants aged 10–79 years in a cross-sectional design. DRF increased from adolescence (ages 10–19) to early adulthood (20–29) and then decreased again for the next 20 years. The nature of this decrease differed for males and females. For males, it began earlier (30–39), proceeded more gradually, and reached a nadir earlier (40–49) than it did for females. For females, it began later (40–49), dropped more abruptly, and reached nadir later (50–59). Marked sex differences were observed for age strata 10–19 through 40–49 and year-by-year analyses estimated the window for these differences to be more precisely from 14 to 44 years. DTD decreased linearly with age for both sexes up to 50–59 and then dropped even more sharply for 60–79. There was a sex difference favoring males on this measure but only for ages 10–19. Findings replicate, in a single sample, those from several previous studies showing an increase in DRF from adolescence to early adulthood, a subsequent decrease primarily in early and middle adulthood, and different patterns of age-related decrease in the two sexes. Age-related changes in sleep structure, such as decreasing %REM sleep which parallel the observed dream recall changes, might help explain these findings, but these sleep changes are much smaller and more gradual in nature. Changes in the phase and amplitude of circadian rhythms of REM propensity and generational differences in life experiences may also account for some part of the findings. That decreases in DTD parallel known age-related decreases in episodic and autobiographical memory may signify that this new diversity measure indexes an aspect of autobiographical memory that also influences dream recall. PMID:22783222

  9. Pathogenesis of Age-Related Bone Loss in Humans

    PubMed Central

    2013-01-01

    Background. Although data from rodent systems are extremely useful in providing insights into possible mechanisms of age-related bone loss, concepts evolving from animal models need to ultimately be tested in humans. Methods. This review provides an update on mechanisms of age-related bone loss in humans based on the author’s knowledge of the field and focused literature reviews. Results. Novel imaging, experimental models, biomarkers, and analytic techniques applied directly to human studies are providing new insights into the patterns of bone mass acquisition and loss as well as the role of sex steroids, in particular estrogen, on bone metabolism and bone loss with aging in women and men. These studies have identified the onset of trabecular bone loss at multiple sites that begins in young adulthood and remains unexplained, at least based on current paradigms of the mechanisms of bone loss. In addition, estrogen appears to be a major regulator of bone metabolism not only in women but also in men. Studies assessing mechanisms of estrogen action on bone in humans have identified effects of estrogen on RANKL expression by several different cell types in the bone microenvironment, a role for TNF-α and IL-1β in mediating effects of estrogen deficiency on bone, and possible regulation of the Wnt inhibitor, sclerostin, by estrogen. Conclusions. There have been considerable advances in our understanding of age-related bone loss in humans. However, there are also significant gaps in knowledge, particularly in defining cell autonomous changes in bone in human studies to test or validate concepts emerging from studies in rodents. Decision Editor: Luigi Ferrucci, MD, PhD PMID:22923429

  10. Circulating miRNAs in Ageing and Ageing-Related Diseases

    PubMed Central

    Jung, Hwa Jin; Suh, Yousin

    2015-01-01

    MicroRNAs (miRNAs) are small non-coding RNAs that negatively regulate gene expression at the post-transcriptional level. They are involved in important biological processes including development, homeostasis, and ageing. Recently, extracellular miRNAs have been discovered in the bloodstream and bodily fluids. These miRNAs are shown to be secreted and circulating in microvesicles (MVs), or in complex with other factors such as RNA-binding proteins and high-density lipoprotein (HDL) particles. These cell-free, circulating miRNAs can be taken into and function as negative regulators of target genes in recipient cells. Here we review the biogenesis and uptake of circulating miRNAs as well as their profiles in ageing and ageing-related diseases. We discuss the emerging role of circulating miRNAs as biomarkers and therapeutic targets. PMID:25269672

  11. THE ENERGY-REDOX AXIS IN AGING AND AGE-RELATED NEURODEGENERATION

    PubMed Central

    Yap, Li-Peng; Garcia, Jerome V.; Han, Derick; Cadenas, Enrique

    2009-01-01

    Decrease in mitochondrial energy-transducing capacity is a feature of the aging process that accompanies redox alterations, such as increased generation of mitochondrial oxidants, altered GSH status, and increased protein oxidation. The decrease in mitochondrial energy-transducing capacity and altered redox status should be viewed as a concerted process that embodies the mitochondrial energy – redox axis and is linked through various mechanisms including: (a) an inter-convertible reducing equivalents pool (i.e., NAD(P)+/NAD(P)H) and (b) redox-mediated protein post-translational modifications involved in energy metabolism. The energy–redox axis provides the rationale for therapeutic approaches targeted to each or both component(s) of the axis that effectively preserves or improve mitochondrial function and that have implications for aging and age-related neurodegenerative disorders. PMID:19716388

  12. The Shergottite Age Paradox and the Relative Probabilities of Ejecting Martian Meteorites of Differing Ages

    NASA Technical Reports Server (NTRS)

    Borg, L. E.; Shih, C.-Y.; Nyquist, L. E.

    1998-01-01

    The apparent paradox that the majority of impacts yielding Martian meteorites appear to have taken place on only a few percent of the Martian surface can be resolved if all the shergottites were ejected in a single event rather than in multiple events as expected from variations in their cosmic ray exposure and crystallization ages. If the shergottite-ejection event is assigned to one of three craters in the vicinity of Olympus Mons that were previously identified as candidate source craters for the SNC (Shergottites, Nakhlites, Chassigny) meteorites, and the nakhlite event to another candidate crater in the vicinity of Ceraunius Tholus, the implied ages of the surrounding terranes agree well with crater density ages. EN,en for high cratering rates (minimum ages), the likely origin of the shergottites is in the Tharsis region, and the paradox of too many meteorites from too little terrane remains for multiple shergottite-ejection events. However, for high cratering rates it is possible to consider sources for the nakhlltes which are away from the Tharsis region. The meteorite-yielding impacts may have been widely dispersed with sources of the young SNC meteorites in the northern plains, and the source of the ancient orthopyroxenite, ALH84001, in the ancient southern uplands. Oblique-impact craters can be identified with the sources of the nakhlites and the orthopyroxenite,, respectively, in the nominal cratering rate model, and with the shergottites and orthopyroxenite, respectively, in the high cratering rate model. Thus, oblique impacts deserve renewed attention as an ejection mechanism for Martian meteorites.

  13. Temperature affects longevity and age-related locomotor and cognitive decay in the short-lived fish Nothobranchius furzeri.

    PubMed

    Valenzano, Dario R; Terzibasi, Eva; Cattaneo, Antonino; Domenici, Luciano; Cellerino, Alessandro

    2006-06-01

    Temperature variations are known to modulate aging and life-history traits in poikilotherms as different as worms, flies and fish. In invertebrates, temperature affects lifespan by modulating the slope of age-dependent acceleration in death rate, which is thought to reflect the rate of age-related damage accumulation. Here, we studied the effects of temperature on aging kinetics, aging-related behavioural deficits, and age-associated histological markers of senescence in the short-lived fish Nothobranchius furzeri. This species shows a maximum captive lifespan of only 3 months, which is tied with acceleration in growth and expression of aging biomarkers. These biological peculiarities make it a very convenient animal model for testing the effects of experimental manipulations on life-history traits in vertebrates. Here, we show that (i) lowering temperature from 25 degrees C to 22 degrees C increases both median and maximum lifespan; (ii) life extension is due to reduction in the slope of the age-dependent acceleration in death rate; (iii) lowering temperature from 25 degrees C to 22 degrees C retards the onset of age-related locomotor and learning deficits; and (iv) lowering temperature from 25 degrees C to 22 degrees C reduces the accumulation of the age-related marker lipofuscin. We conclude that lowering water temperature is a simple experimental manipulation which retards the rate of age-related damage accumulation in this short-lived species. PMID:16842500

  14. Age related susceptibility of pigs to Cryptosporidium scrofarum infection.

    PubMed

    Kváč, Martin; Němejc, Karel; Kestřánová, Michaela; Květoňová, Dana; Wagnerová, Pavla; Kotková, Michaela; Rost, Michael; Samková, Eva; McEvoy, John; Sak, Bohumil

    2014-05-28

    Piglets from 4 to 8 weeks of age originated from a Cryptosporidium-free research breed were orally inoculated with 1 × 10(6) infectious oocysts of Cryptosporidium scrofarum. The number of shed oocysts per gram of faeces served to describe the infection intensity and prepatent period. In addition, faecal samples collected daily and tissue samples of the small and large intestine collected at 30 days post-inoculation were examined for the C. scrofarum small subunit ribosomal RNA gene using PCR. The piglets inoculated at 4-weeks of age remained uninfected, whereas 5-week-old and older animals were fully susceptible with a prepatent period ranging from 4 to 8 days. Susceptible pigs shed oocysts intermittently, and shedding intensity, reaching a mean maximum of 6000 oocysts per gram, did not differ significantly among infected animals. This study demonstrates that pigs become susceptible to C. scrofarum infection as late as 5-weeks of age. The mechanisms of age related susceptibility remain unknown. PMID:24630710

  15. Relative age effects in professional German soccer: a historical analysis.

    PubMed

    Cobley, Stephen P; Schorer, Joerg; Baker, Joseph

    2008-12-01

    Relative age effects (RAEs) refer to the specific selection, participation and attainment (dis)advantages which occur as a result of physical and cognitive differences within annual age-grouped cohorts. The present study tracked the existence of RAEs in professional German soccer by examining RAEs in players, head coaches and referees who represented professional soccer clubs or officiated in the Bundesliga from 1963/64 to 2006/07. An additional objective was to consider the social-cultural mechanisms responsible for RAEs, so for a similar period, population and soccer participation information was also obtained. When players were categorised into half decade groups, chi-square analyses predominantly showed RAEs across the history of the Bundesliga, irrespective of dates used for annual age grouping in junior/youth soccer. RAEs were also apparent for head coaches but not for referees. Participation data indicated consistent and progressive growth from 1950 to 1990. RAEs influence the likelihood of attaining professional player and coaching status in German soccer. With many coaches being former players, inequalities associated with annual age-grouping appear to extend beyond a playing career. Officiating was not affected, with referees suggested to emerge from an alternative development pathway. Increased popularity of soccer may have propagated RAEs over time, through intensification of competition and selection mechanisms. PMID:19040189

  16. Structural basis of growth-related gain and age-related loss of bone strength

    PubMed Central

    2008-01-01

    If bone strength was the only requirement of skeleton, it could be achieved with bulk, but bone must also be light. During growth, bone modelling and remodelling optimize strength, by depositing bone where it is needed, and minimize mass, by removing it from where it is not. The population variance in bone traits is established before puberty and the position of an individual's bone size and mass tracks in the percentile of origin. Larger cross-sections have a comparably larger marrow cavity, which results in a lower volumetric BMD (vBMD), thereby avoiding bulk. Excavation of a marrow cavity thus minimizes mass and shifts the cortex radially, increasing rigidity. Smaller cross-sections are assembled by excavating a smaller marrow cavity leaving a relatively thicker cortex producing a higher vBMD, avoiding the fragility of slenderness. Variation in cellular activity around the periosteal and endocortical envelopes fashions the diverse shapes of adjacent cross-sections. Advancing age is associated with a decline in periosteal bone formation, a decline in the volume of bone formed by each basic multicellular unit (BMU), continued resorption by each BMU, and high remodelling after menopause. Bone loss in young adulthood has modest structural and biomechanical consequences because the negative BMU balance is driven by reduced bone formation, remodelling is slow and periosteal apposition continues shifting the thinned cortex radially. But after the menopause, increased remodelling, worsening negative BMU balance and a decline in periosteal apposition accelerate cortical thinning and porosity, trabecular thinning and loss of connectivity. Interstitial bone, unexposed to surface remodelling becomes more densely mineralized, has few osteocytes and greater collagen cross-linking, and accumulates microdamage. These changes produce the material and structural abnormalities responsible for bone fragility. PMID:18556646

  17. The effect of normal aging and age-related macular degeneration on perceptual learning.

    PubMed

    Astle, Andrew T; Blighe, Alan J; Webb, Ben S; McGraw, Paul V

    2015-01-01

    We investigated whether perceptual learning could be used to improve peripheral word identification speed. The relationship between the magnitude of learning and age was established in normal participants to determine whether perceptual learning effects are age invariant. We then investigated whether training could lead to improvements in patients with age-related macular degeneration (AMD). Twenty-eight participants with normal vision and five participants with AMD trained on a word identification task. They were required to identify three-letter words, presented 10° from fixation. To standardize crowding across each of the letters that made up the word, words were flanked laterally by randomly chosen letters. Word identification performance was measured psychophysically using a staircase procedure. Significant improvements in peripheral word identification speed were demonstrated following training (71% ± 18%). Initial task performance was correlated with age, with older participants having poorer performance. However, older adults learned more rapidly such that, following training, they reached the same level of performance as their younger counterparts. As a function of number of trials completed, patients with AMD learned at an equivalent rate as age-matched participants with normal vision. Improvements in word identification speed were maintained at least 6 months after training. We have demonstrated that temporal aspects of word recognition can be improved in peripheral vision with training across a range of ages and these learned improvements are relatively enduring. However, training targeted at other bottlenecks to peripheral reading ability, such as visual crowding, may need to be incorporated to optimize this approach. PMID:26605694

  18. The effect of normal aging and age-related macular degeneration on perceptual learning

    PubMed Central

    Astle, Andrew T.; Blighe, Alan J.; Webb, Ben S.; McGraw, Paul V.

    2015-01-01

    We investigated whether perceptual learning could be used to improve peripheral word identification speed. The relationship between the magnitude of learning and age was established in normal participants to determine whether perceptual learning effects are age invariant. We then investigated whether training could lead to improvements in patients with age-related macular degeneration (AMD). Twenty-eight participants with normal vision and five participants with AMD trained on a word identification task. They were required to identify three-letter words, presented 10° from fixation. To standardize crowding across each of the letters that made up the word, words were flanked laterally by randomly chosen letters. Word identification performance was measured psychophysically using a staircase procedure. Significant improvements in peripheral word identification speed were demonstrated following training (71% ± 18%). Initial task performance was correlated with age, with older participants having poorer performance. However, older adults learned more rapidly such that, following training, they reached the same level of performance as their younger counterparts. As a function of number of trials completed, patients with AMD learned at an equivalent rate as age-matched participants with normal vision. Improvements in word identification speed were maintained at least 6 months after training. We have demonstrated that temporal aspects of word recognition can be improved in peripheral vision with training across a range of ages and these learned improvements are relatively enduring. However, training targeted at other bottlenecks to peripheral reading ability, such as visual crowding, may need to be incorporated to optimize this approach. PMID:26605694

  19. Population-Based Age Group Specific Annual Incidence Rates of Symptomatic Age-Related Macular Degeneration

    PubMed Central

    Saari, Jukka M

    2014-01-01

    Purpose To study the population-based annual incidence rates of exudative, dry and all cases of symptomatic age-related macular degeneration (AMD) in different age and sex groups. Methods. This is a one year, prospective, population-based study on all consecutive new patients with AMD in the hospital district of Central Finland. The diagnosis was confirmed in all patients with slit lamp biomicroscopy, optical coherence tomography (OCT) using a Spectralis HRA + OCT device, and the Heidelberg Eye Explorer 1.6.2.0 program. Fluorescein angiograms were taken when needed. Results. The population-based annual incidence rates of all cases of symptomatic AMD increased from 0.03% (95% CI, 0.01-0.05%) in the age group 50-59 years to 0.82% (95% CI, 0.55-1.09%) in the age group 85-89 years and were 0.2% (95% CI, 0.17-0.24%) in exudative, 0.11% (95% CI, 0.09-0.14%) in dry, and 0.32% (95% CI, 0.28-0.36%) in all cases of AMD in the age group 60 years and older. During the next 20 years in Central Finland the population-based annual incidence rates can be estimated to increase to 0.27% (95% CI, 0.24-0.30%) in exudative, to 0.13% (95% CI, 0.11-0.15%) in dry, and to 0.41% (95% CI, 0.37-0.45%) in all cases of AMD in the age group 60 years and older. The population-based annual incidence of AMD did not show statistically significant differences between males and females (p>0.1). Conclusion: The population-based age-group specific annual incidence rates of symptomatic AMD of this study may help to plan health care provision for patients of AMD. PMID:25674187

  20. FENNOSTACK and FENNORPIS: Varve dated Holocene palaeomagnetic secular variation and relative palaeointensity stacks for Fennoscandia

    NASA Astrophysics Data System (ADS)

    Snowball, Ian; Zillén, Lovisa; Ojala, Antti; Saarinen, Timo; Sandgren, Per

    2007-03-01

    A Holocene palaeomagnetic secular variation master curve (FENNOSTACK) and a relative palaeointensity curve (FENNORPIS) for Fennoscandia are presented. These curves were produced by stacking palaeomagnetic data obtained from six annually laminated (varved) lake sediment sequences and one non-laminated sediment sequence. The six independent varve chronologies were combined to form a timescale, which extends between the present year and 10,200 Cal yr BP. Smoothed inclination and declination curves show trends that are similar to a palaeomagnetic secular variation curve for the United Kingdom, except that the ages of most of the statistically significant features are a few hundred years younger in the Fennoscandian data set. These differences are most likely due to excessively old ages of the United Kingdom features produced by the radiocarbon dating of bulk sediments. The standardized relative palaeointensity stack shows that the intensity of the geomagnetic field in Fennoscandia was highest at 2300 Cal yr BP and lowest at 7000 Cal yr BP. Three palaeointensity peaks (PIPs) and three palaeointensity lows (PILs) are identified in FENNORPIS and indicate that the intensity of geomagnetic field varied significantly on millennial scales in this region during the Holocene, but there is much scatter in the reconstruction prior to 8000 Cal yr BP. Higher frequency palaeointensity features present in individual records are not significant in the stacked data set, which implies that these are a result of local environmental bias. Significant discrepancies exist between the data and the output of the CALS7K.2 geomagnetic field model for the last 7000 yr. In particular, the largest declination swing observed in the data at 2670 Cal yr BP (feature "f") is not produced by the model, which is most likely due to the influence of an inaccurately dated Icelandic secular variation curve on the model result. Short term trends in standardized relative palaeointensity do differ from the

  1. Neural Alterations in Acquired Age-Related Hearing Loss

    PubMed Central

    Mudar, Raksha A.; Husain, Fatima T.

    2016-01-01

    Hearing loss is one of the most prevalent chronic health conditions in older adults. Growing evidence suggests that hearing loss is associated with reduced cognitive functioning and incident dementia. In this mini-review, we briefly examine literature on anatomical and functional alterations in the brains of adults with acquired age-associated hearing loss, which may underlie the cognitive consequences observed in this population, focusing on studies that have used structural and functional magnetic resonance imaging, diffusion tensor imaging, and event-related electroencephalography. We discuss structural and functional alterations observed in the temporal and frontal cortices and the limbic system. These neural alterations are discussed in the context of common cause, information-degradation, and sensory-deprivation hypotheses, and we suggest possible rehabilitation strategies. Although, we are beginning to learn more about changes in neural architecture and functionality related to age-associated hearing loss, much work remains to be done. Understanding the neural alterations will provide objective markers for early identification of neural consequences of age-associated hearing loss and for evaluating benefits of intervention approaches. PMID:27313556

  2. Deriving Age-Activity Relations in M Dwarf Stars Using Clusters of Known Ages

    NASA Astrophysics Data System (ADS)

    Andersen, J. M.; West, A. A.; Covey, K. R.; McDonald, M.; Veilleux, S.; Seth, A.

    2011-12-01

    We present preliminary results from a study of M dwarf magnetic activity in clusters of known ages with the ultimate goal of constraining the age-activity relation. The age-activity relation provides clues to the mechanisms generating magnetic dynamos, especially in late-type dwarfs where their stellar interiors become fully convective. Broadband griz photometry was obtained for four clusters with ages ranging from ˜110 Myrs to 4 Gyrs. Narrowband images of each cluster were acquired with the Maryland Magellan Tunable Filter, tuned to the frequency of Hα, including a correction for the cluster's radial velocity, and a nearby, similarly sized bandpass sampling the stellar pseudo-continuum. This permits a "photometric" measurement of the Hα emission for each star, and thus a measure of activity. Cluster membership is determined from broadband photometry and comparison to stellar positions from previous studies. We report on our findings for the cluster NGC 2516. Hα measurements are stronger for cluster stars than for field stars of the same magnitude. A clear correlation is seen between our Hα strengths measured by narrowband imaging and previous spectroscopic activity measurements for stars where spectra have been obtained.

  3. Plumage development and molt in Long-tailed Manakins (Chiroxiphia linearis): Variation according to sex and age

    USGS Publications Warehouse

    Doucet, S.M.; McDonald, D.B.; Foster, M.S.; Clay, R.P.

    2007-01-01

    Lek-mating Long-tailed Manakins (Chiroxiphia linearis) exhibit an unusual pattern of delayed plumage maturation. Each year, males progress through a series of predefinitive plumages before attaining definitive plumage in their fifth calendar year. Females also exhibit variation in plumage coloration, with some females displaying male-like plumage characteristics. Using data from mist-net captures in northwest Costa Rica (n = 1,315) and museum specimens from throughout the range of Long-tailed Manakins (n = 585), we documented the plumage sequence progression of males, explored variation in female plumage, and described the timing of molt in this species. Males progressed through a series of age-specific predefinitive plumages, which enabled the accurate aging of predefinitive-plumaged males in the field; this preclefinitive plumage sequence is the basis for age-related status- signaling in these males. Females tended to acquire red coloration in the crown as they aged. However, colorful plumage in females may be a byproduct of selection on bright male plumage. Females exhibited an early peak of molt activity from February to April, little molt from May through July, and a second, more pronounced peak of molt activity in October. By contrast, males in older predefinitive-plumage stages and males in definitive plumage exhibited comparable unimodal distributions in molt activity beginning in June and peaking between July and October. Our data are consistent with selective pressure to avoid the costs of molt-breeding overlap in females and older males. Our findings have important implications for social organization and signaling in Longtailed Manakins, and for the evolution of delayed plumage maturation in birds.

  4. Symplectic structures related with higher order variational problems

    NASA Astrophysics Data System (ADS)

    Kijowski, Jerzy; Moreno, Giovanni

    2015-06-01

    In this paper, we derive the symplectic framework for field theories defined by higher order Lagrangians. The construction is based on the symplectic reduction of suitable spaces of iterated jets. The possibility of reducing a higher order system of partial differential equations to a constrained first-order one, the symplectic structures naturally arising in the dynamics of a first-order Lagrangian theory, and the importance of the Poincaré-Cartan form for variational problems, are all well-established facts. However, their adequate combination corresponding to higher order theories is missing in the literature. Here we obtain a consistent and truly finite-dimensional canonical formalism, as well as a higher order version of the Poincaré-Cartan form. In our exposition, the rigorous global proofs of the main results are always accompanied by their local coordinate descriptions, indispensable to work out practical examples.

  5. Age related flow rate nomograms in a normal pediatric population.

    PubMed

    Gaum, L D; Wese, F X; Liu, T P; Wong, A K; Hardy, B E; Churchill, B M

    1989-01-01

    Uroflow studies in a normal pediatric population were analysed statistically. Single studies for 511 subjects (272 boys and 239 girls) were reviewed. Nomograms relating peak flow to volume voided and age were established. An acceptable lower limit for peak flow was obtained from the data and a volume voided range was calculated so that both criteria could be used with 90% probability to define the normal voiding situation. The mean values of peak flow rate increased with volume voided in both sexes and also with age in the male population. Different sets of nomograms, which are necessary for daily clinical evaluation, are given. They define the normal values in the normal population. PMID:2763925

  6. Age-related changes in skin barrier function - quantitative evaluation of 150 female subjects.

    PubMed

    Luebberding, S; Krueger, N; Kerscher, M

    2013-04-01

    The protection against water loss and the prevention of substances and bacteria penetrating into the body rank as the most important functions of the skin. This so-called 'skin barrier function' is the natural frontier between the inner organism and the environment, and is primarily formed by the epidermis. An impairment of the skin barrier function is often found in diseased and damaged skin. An influence of ageing on skin barrier function is widely accepted, but has not been conclusively evaluated yet. Therefore, the aim of this clinical study was to assess the potential influence of ageing on skin barrier function, including transepidermal water loss (TEWL), stratum corneum hydration, sebum content and pH value. One hundred and fifty healthy women aged 18-80, divided into five age groups with 30 subjects each, were evaluated in this study. TEWL, hydration level, sebum secretion and pH value of hydro-lipid acid film were measured with worldwide acknowledged biophysical measuring methods at cheek, neck, décolleté, volar forearm and dorsum of hand. Whereas TEWL and stratum corneum hydration showed only very low correlation with subject's age, the sebum production decreased significantly with age, resulting in the lowest skin surface lipids levels measured in subjects older than 70 years. The highest skin surface pH was measured in subjects between 50 and 60 years, whereas the eldest age group had the lowest mean pH. The dorsum of the hand was the location with the highest TEWL and lowest stratum corneum hydration in all age groups. The results show that only some parameters related to skin barrier function are influenced by ageing. Whereas sebum production decreases significantly over lifetime and skin surface pH is significantly increased in menopausal woman, TEWL and stratum corneum hydration show only minor variations with ageing. PMID:23113564

  7. Aging-related tau astrogliopathy (ARTAG): harmonized evaluation strategy.

    PubMed

    Kovacs, Gabor G; Ferrer, Isidro; Grinberg, Lea T; Alafuzoff, Irina; Attems, Johannes; Budka, Herbert; Cairns, Nigel J; Crary, John F; Duyckaerts, Charles; Ghetti, Bernardino; Halliday, Glenda M; Ironside, James W; Love, Seth; Mackenzie, Ian R; Munoz, David G; Murray, Melissa E; Nelson, Peter T; Takahashi, Hitoshi; Trojanowski, John Q; Ansorge, Olaf; Arzberger, Thomas; Baborie, Atik; Beach, Thomas G; Bieniek, Kevin F; Bigio, Eileen H; Bodi, Istvan; Dugger, Brittany N; Feany, Mel; Gelpi, Ellen; Gentleman, Stephen M; Giaccone, Giorgio; Hatanpaa, Kimmo J; Heale, Richard; Hof, Patrick R; Hofer, Monika; Hortobágyi, Tibor; Jellinger, Kurt; Jicha, Gregory A; Ince, Paul; Kofler, Julia; Kövari, Enikö; Kril, Jillian J; Mann, David M; Matej, Radoslav; McKee, Ann C; McLean, Catriona; Milenkovic, Ivan; Montine, Thomas J; Murayama, Shigeo; Lee, Edward B; Rahimi, Jasmin; Rodriguez, Roberta D; Rozemüller, Annemieke; Schneider, Julie A; Schultz, Christian; Seeley, William; Seilhean, Danielle; Smith, Colin; Tagliavini, Fabrizio; Takao, Masaki; Thal, Dietmar Rudolf; Toledo, Jon B; Tolnay, Markus; Troncoso, Juan C; Vinters, Harry V; Weis, Serge; Wharton, Stephen B; White, Charles L; Wisniewski, Thomas; Woulfe, John M; Yamada, Masahito; Dickson, Dennis W

    2016-01-01

    Pathological accumulation of abnormally phosphorylated tau protein in astrocytes is a frequent, but poorly characterized feature of the aging brain. Its etiology is uncertain, but its presence is sufficiently ubiquitous to merit further characterization and classification, which may stimulate clinicopathological studies and research into its pathobiology. This paper aims to harmonize evaluation and nomenclature of aging-related tau astrogliopathy (ARTAG), a term that refers to a morphological spectrum of astroglial pathology detected by tau immunohistochemistry, especially with phosphorylation-dependent and 4R isoform-specific antibodies. ARTAG occurs mainly, but not exclusively, in individuals over 60 years of age. Tau-immunoreactive astrocytes in ARTAG include thorn-shaped astrocytes at the glia limitans and in white matter, as well as solitary or clustered astrocytes with perinuclear cytoplasmic tau immunoreactivity that extends into the astroglial processes as fine fibrillar or granular immunopositivity, typically in gray matter. Various forms of ARTAG may coexist in the same brain and might reflect different pathogenic processes. Based on morphology and anatomical distribution, ARTAG can be distinguished from primary tauopathies, but may be concurrent with primary tauopathies or other disorders. We recommend four steps for evaluation of ARTAG: (1) identification of five types based on the location of either morphologies of tau astrogliopathy: subpial, subependymal, perivascular, white matter, gray matter; (2) documentation of the regional involvement: medial temporal lobe, lobar (frontal, parietal, occipital, lateral temporal), subcortical, brainstem; (3) documentation of the severity of tau astrogliopathy; and (4) description of subregional involvement. Some types of ARTAG may underlie neurological symptoms; however, the clinical significance of ARTAG is currently uncertain and awaits further studies. The goal of this proposal is to raise awareness of

  8. Age-related oxidative modifications of transthyretin modulate its amyloidogenicity

    PubMed Central

    Zhao, Lei; Buxbaum, Joel N; Reixach, Natàlia

    2013-01-01

    The transthyretin amyloidoses are diseases of protein misfolding characterized by the extracellular deposition of fibrils and other aggregates of the homotetrameric protein transthyretin (TTR) in peripheral nerves, heart and other tissues. Age is the major risk factor for the development of these diseases. We hypothesized that an age-associated increase in protein oxidation could be involved in the onset of the senile forms of the TTR amyloidoses. To test this hypothesis we have produced and characterized relevant age-related oxidative modifications of wild type (WT) and the Val122Ile (V122I) TTR variant, both involved in cardiac TTR deposition in the elderly. Our studies show that methionine/cysteine oxidized TTR and carbonylated TTR either from WT or the V122I variant, are thermodynamically less stable than their non-oxidized counterparts. Moreover, carbonylated WT and carbonylated V122I TTR have a greater propensity to form aggregates and fibrils than WT and V122I TTR, respectively, at physiologically attainable pH. It is well known that TTR tetramer dissociation, the limiting step for aggregation and amyloid fibril formation, can be prevented by small molecules that bind the TTR tetramer interface. Here, we report that carbonylated WT TTR is less amenable to resveratrol-mediated tetramer stabilization than WT TTR. All the oxidized forms of TTR tested are cytotoxic to a human cardiomyocyte cell line known to be a target for cardiac-specific TTR variants. Overall these studies demonstrate that age-related oxidative modifications of TTR can contribute to the onset of the senile forms of the TTR amyloidoses. PMID:23414091

  9. Age-related oxidative modifications of transthyretin modulate its amyloidogenicity.

    PubMed

    Zhao, Lei; Buxbaum, Joel N; Reixach, Natàlia

    2013-03-19

    The transthyretin amyloidoses are diseases of protein misfolding characterized by the extracellular deposition of fibrils and other aggregates of the homotetrameric protein transthyretin (TTR) in peripheral nerves, heart, and other tissues. Age is the major risk factor for the development of these diseases. We hypothesized that an age-associated increase in the level of protein oxidation could be involved in the onset of the senile forms of the TTR amyloidoses. To test this hypothesis, we have produced and characterized relevant age-related oxidative modifications of the wild type (WT) and the Val122Ile (V122I) TTR variant, both involved in cardiac TTR deposition in the elderly. Our studies show that methionine/cysteine-oxidized TTR and carbonylated TTR from either the WT or the V122I variant are thermodynamically less stable than their nonoxidized counterparts. Moreover, carbonylated WT and carbonylated V122I TTR have a stronger propensity to form aggregates and fibrils than WT and V122I TTR, respectively, at physiologically attainable pH values. It is well-known that TTR tetramer dissociation, the limiting step for aggregation and amyloid fibril formation, can be prevented by small molecules that bind the TTR tetramer interface. Here, we report that carbonylated WT TTR is less amenable to resveratrol-mediated tetramer stabilization than WT TTR. All the oxidized forms of TTR tested are cytotoxic to a human cardiomyocyte cell line known to be a target for cardiac-specific TTR variants. Overall, these studies demonstrate that age-related oxidative modifications of TTR can contribute to the onset of the senile forms of the TTR amyloidoses. PMID:23414091

  10. Age-related changes in the tiger salamander retina.

    PubMed

    Townes-Anderson, E; Colantonio, A; St Jules, R S

    1998-05-01

    Tiger salamanders have been used in visual science because of the large size of their cells and the ease of preparation and maintenance of in vitro retinal preparations. We have found that salamanders over 27 cm in length show a variety of visual abnormalities. Compared to smaller animals (15-23 cm), large animals exhibited a decrease in visual responses determined by tests of the optomotor reflex. Small animals responded correctly an average of 84.5% of the time in visual testing at three light levels compared to an average of 68.4% for the large animals with the poorest visual performance at the lowest level of illumination. In addition, large animals contained (i) histological degeneration of the outer retina, in particular, loss and disruption of outer segments and abnormalities of the retinal pigmented epithelium, (ii) loss of cells, including photoreceptors, by apoptosis as evaluated with the TUNEL technique, and (iii) an increase in the number of macrophages and lymphocytes within the retina as determined by morphological examination. These histological changes were present in all large animals and all quadrants of their retinas. In contrast, small animals showed virtually no retinal degeneration, no TUNEL-positive cells, and few immune-like cells in the retina. Since large animals are also older animals. the visual changes are age-related. Loss of visual function and histological degeneration in the outer retina also typify aged human eyes. Thus, we propose that large salamanders serve as an animal model for age-related retinal degeneration. In addition to providing a source of aging retina that is readily accessible to experimental manipulation, the salamander provides a pigmented retina with a mixed (2:1, rod:cone) population of photoreceptors, similar to the degeneration-prone parafoveal region of the human eye. PMID:9631666

  11. Circulating inflamma-miRs in aging and age-related diseases

    PubMed Central

    Olivieri, Fabiola; Rippo, Maria R.; Procopio, Antonio D.; Fazioli, Francesca

    2013-01-01

    Evidence on circulating microRNAs (miRNAs) is indisputably opening a new era in systemic and tissue-specific biomarker research, highlighting new inter-cellular and inter-organ communication mechanisms. Circulating miRNAs might be active messengers eliciting a systemic response as well as non-specific “by-products” of cell activity and even of cell death; in either case they have the potential to be clinically relevant biomarkers for a number of physiopathological processes, including inflammatory responses and inflammation-related conditions. A large amount of evidence indicates that miRNAs can exert two opposite roles, activating as well as inhibiting inflammatory pathways. The inhibitory action probably relates to the need for activating anti-inflammatory mechanisms to counter potent proinflammatory signals, like the nuclear factor kappaB (NF-κB) pathway, to prevent cell and tissue destruction. MiRNA-based anti-inflammatory mechanisms may acquire a crucial role during aging, where a chronic, low-level proinflammatory status is likely sustained by the cell senescence secretome and by progressive activation of immune cells over time. This process entails age-related changes, especially in extremely old age, in those circulating miRNAs that are capable of modulating the inflammatory status (inflamma-miRs). Interestingly, a number of such circulating miRNAs seem to be promising biomarkers for the major age-related diseases that share a common chronic, low-level proinflammatory status, such as cardiovascular disease (CVD), type 2 diabetes mellitus (T2DM), Alzheimer Disease (AD), rheumatoid arthritis (RA), and cancers. PMID:23805154

  12. Hypoxia-Inducible Histone Lysine Demethylases: Impact on the Aging Process and Age-Related Diseases

    PubMed Central

    Salminen, Antero; Kaarniranta, Kai; Kauppinen, Anu

    2016-01-01

    Hypoxia is an environmental stress at high altitude and underground conditions but it is also present in many chronic age-related diseases, where blood flow into tissues is impaired. The oxygen-sensing system stimulates gene expression protecting tissues against hypoxic insults. Hypoxia stabilizes the expression of hypoxia-inducible transcription factor-1α (HIF-1α), which controls the expression of hundreds of survival genes related to e.g. enhanced energy metabolism and autophagy. Moreover, many stress-related signaling mechanisms, such as oxidative stress and energy metabolic disturbances, as well as the signaling cascades via ceramide, mTOR, NF-κB, and TGF-β pathways, can also induce the expression of HIF-1α protein to facilitate cell survival in normoxia. Hypoxia is linked to prominent epigenetic changes in chromatin landscape. Screening studies have indicated that the stabilization of HIF-1α increases the expression of distinct histone lysine demethylases (KDM). HIF-1α stimulates the expression of KDM3A, KDM4B, KDM4C, and KDM6B, which enhance gene transcription by demethylating H3K9 and H3K27 sites (repressive epigenetic marks). In addition, HIF-1α induces the expression of KDM2B and KDM5B, which repress transcription by demethylating H3K4me2,3 sites (activating marks). Hypoxia-inducible KDMs support locally the gene transcription induced by HIF-1α, although they can also control genome-wide chromatin landscape, especially KDMs which demethylate H3K9 and H3K27 sites. These epigenetic marks have important role in the control of heterochromatin segments and 3D folding of chromosomes, as well as the genetic loci regulating cell type commitment, proliferation, and cellular senescence, e.g. the INK4 box. A chronic stimulation of HIF-1α can provoke tissue fibrosis and cellular senescence, which both are increasingly present with aging and age-related diseases. We will review the regulation of HIF-1α-dependent induction of KDMs and clarify their role in

  13. Hypoxia-Inducible Histone Lysine Demethylases: Impact on the Aging Process and Age-Related Diseases.

    PubMed

    Salminen, Antero; Kaarniranta, Kai; Kauppinen, Anu

    2016-03-01

    Hypoxia is an environmental stress at high altitude and underground conditions but it is also present in many chronic age-related diseases, where blood flow into tissues is impaired. The oxygen-sensing system stimulates gene expression protecting tissues against hypoxic insults. Hypoxia stabilizes the expression of hypoxia-inducible transcription factor-1α (HIF-1α), which controls the expression of hundreds of survival genes related to e.g. enhanced energy metabolism and autophagy. Moreover, many stress-related signaling mechanisms, such as oxidative stress and energy metabolic disturbances, as well as the signaling cascades via ceramide, mTOR, NF-κB, and TGF-β pathways, can also induce the expression of HIF-1α protein to facilitate cell survival in normoxia. Hypoxia is linked to prominent epigenetic changes in chromatin landscape. Screening studies have indicated that the stabilization of HIF-1α increases the expression of distinct histone lysine demethylases (KDM). HIF-1α stimulates the expression of KDM3A, KDM4B, KDM4C, and KDM6B, which enhance gene transcription by demethylating H3K9 and H3K27 sites (repressive epigenetic marks). In addition, HIF-1α induces the expression of KDM2B and KDM5B, which repress transcription by demethylating H3K4me2,3 sites (activating marks). Hypoxia-inducible KDMs support locally the gene transcription induced by HIF-1α, although they can also control genome-wide chromatin landscape, especially KDMs which demethylate H3K9 and H3K27 sites. These epigenetic marks have important role in the control of heterochromatin segments and 3D folding of chromosomes, as well as the genetic loci regulating cell type commitment, proliferation, and cellular senescence, e.g. the INK4 box. A chronic stimulation of HIF-1α can provoke tissue fibrosis and cellular senescence, which both are increasingly present with aging and age-related diseases. We will review the regulation of HIF-1α-dependent induction of KDMs and clarify their role in

  14. Mathematical morphologic analysis of aging-related epidermal changes.

    PubMed

    Moragas, A; Castells, C; Sans, M

    1993-04-01

    Fractographic techniques based on mathematical morphology were used to study aging-related epidermal changes in abdominal skin samples obtained from 96 autopsy cases. Three linear roughness indices were evaluated for the rete peg profile and the shrinkage effect on the basal layer and interface between the granular and horny layers. Elderly subjects had a 36.3% decrease in rete peg-related roughness index when compared with younger subjects. This roughness index has been corrected, with shrinkage due to skin elasticity taken into account. For females, fitting of a logistic decay function yielded a curve with right and left asymptotes and a steeper descent between 40 and 60 years. Half value time--i.e., the time when half rete peg profile flattening occurred--was 46.8 years. In contrast, males showed almost monotonical decay. Epidermal thickness measured between rete pegs showed the same exponential decline for both sexes, with values from 22.6 to 11.4 microns. Skin shrinkage in elderly subjects decreased 22% in superficial layers and only 6% in the lower epidermis. In both cases shrinkage had a linear relation with age, and no sex differences were found. PMID:8318130

  15. The Theory Behind the Age-Related Positivity Effect

    PubMed Central

    Reed, Andrew E.; Carstensen, Laura L.

    2012-01-01

    The “positivity effect” refers to an age-related trend that favors positive over negative stimuli in cognitive processing. Relative to their younger counterparts, older people attend to and remember more positive than negative information. Since the effect was initially identified and the conceptual basis articulated (Mather and Carstensen, 2005) scores of independent replications and related findings have appeared in the literature. Over the same period, a number of investigations have failed to observe age differences in the cognitive processing of emotional material. When findings are considered in theoretical context, a reliable pattern of evidence emerges that helps to refine conceptual tenets. In this article we articulate the operational definition and theoretical foundations of the positivity effect and review the empirical evidence based on studies of visual attention, memory, decision making, and neural activation. We conclude with a discussion of future research directions with emphasis on the conditions where a focus on positive information may benefit and/or impair cognitive performance in older people. PMID:23060825

  16. Rejuvenation of senescent cells-the road to postponing human aging and age-related disease?

    PubMed

    Sikora, Ewa

    2013-07-01

    Cellular senescence is the state of permanent inhibition of cell proliferation. Replicative senescence occurs due to the end replication problem and shortening telomeres with each cell division leading to DNA damage response (DDR). The number of short telomeres increases with age and age-related pathologies. Stress induced senescence, although not accompanied by attrition of telomeres, is also attributed to the DDR induced by irreparable DNA lesions in telomeric DNA. Senescent cells characterized by the presence of γH2AX, the common marker of double DNA strand breaks, and other senescence markers including activity of SA-β-gal, accumulate in tissues of aged animals and humans as well as at sites of pathology. It is believed that cellular senescence evolved as a cancer barrier since non-proliferating senescent cells cannot be transformed to neoplastic cells. On the other hand senescent cells favor cancer development, just like other age-related pathologies, by creating a low grade inflammatory state due to senescence associated secretory phenotype (SASP). Reversal/inhibition of cellular senescence could prolong healthy life span, thus many attempts have been undertaken to influence cellular senescence. The two main approaches are genetic and pharmacological/nutritional modifications of cell fate. The first one concerns cell reprogramming by induced pluripotent stem cells (iPSCs), which in vitro is effective even in cells undergoing senescence, or derived from very old or progeroid patients. The second approach concerns modification of senescence signaling pathways just like TOR-induced by pharmacological or with natural agents. However, knowing that aging is unavoidable we cannot expect its elimination, but prolonging healthy life span is a goal worth serious consideration. PMID:23064316

  17. Cervical spine geometry in the automotive seated posture: variations with age, stature, and gender.

    PubMed

    Desantis Klinich, Kathleen; Ebert, Sheila M; Van Ee, Chris A; Flannagan, Carol A C; Prasad, Monica; Reed, Matthew P; Schneider, Lawrence W

    2004-11-01

    In the mid 1970s, UMTRI investigated the biomechanical properties of the head and neck using 180 "normal" adult subjects selected to fill eighteen subject groups based on age (young, mid-aged, older), gender, and stature (short, medium, and tall by gender). Lateral-view radiographs of the subjects' cervical spines and heads were taken with the subjects seated in a simulated automotive neutral posture, as well as with their necks in full-voluntary flexion and full-voluntary extension. Although the cervical spine and lower head geometry were previously measured manually and documented, new technologies have enabled computer digitization of the scanned x-ray images and a more comprehensive and detailed analysis of the variation in cervical spine and lower head geometry with subject age, stature, and gender. After scanning the radiographic images, 108 skeletal landmarks on the cervical vertebrae and 10 head landmarks were digitized. The resulting database of cervical spine and head geometry was used to study cervical spine curvature, vertebral dimensions, and head/neck orientation as functions of age, gender, and stature. The data were used to characterize neutral posture cervical spine curvatures using two methods: a curvature index and Bézier spline functions. Lateral-view vertebral dimensions were also calculated for each subject, and a cascading series of equations was developed to estimate vertebral size and shape for a selected age, stature, and gender. The orientation of the cervical spine was defined using a neck chord angle, where the neck chord was varied to use different anatomical landmarks and estimates of joint centers for the top and bottom of the neck chord. Results from the study have been incorporated into a MS-Access based software package that allows researchers and modelers to generate cervical spine geometries for occupants of a specified age, gender, and stature. The program allows selection of individual occupants from the database that meet

  18. North Atlantic surface ocean radiocarbon reservoir age variation: links to rapid global climate change

    NASA Astrophysics Data System (ADS)

    Austin, W. E. N.; Brown, L.; Telford, R. J.; Ninnemann, U. S.; Wilson, L. J.; Bryant, C. L.

    2009-04-01

    High resolution palaeoclimate records show that the overall warming throughout the late glacial period to the present has been punctuated by repeated cooling events on decadal to centennial timescales. Reorganisation of the North Atlantic's deep water thermohaline circulation is often considered an important factor in triggering or controlling these abrupt climate change intervals. During the Younger Dryas (YD), the most significant of these late glacial climatic coolings, a large, positive anomaly in atmospheric radiocarbon concentration (Δ14Catm) is observed, which is not fully accounted for by changes in the production rate of 14C. Another potential source of Δ14Catm variation is the extent of carbon exchange between the atmosphere and other reservoirs, such as the deep ocean, and it has been suggested that the circulation changes which drove the YD cooling were also partially responsible for limiting air-sea CO2 exchange and hence increasing Δ14Catm. Reconstructions of North Atlantic surface ocean radiocarbon reservoir ages (Rt) during the Younger Dryas, based on known-age markers such as tephra horizons, demonstrate an increase in Rt from modern values of 400 y to >800 y, widely believed to be indicative of reduced carbon exchange between the atmosphere and the deep ocean. However, the limited temporal resolution of these measurements has thus far been insufficient to fully explore the connection between changing Rt and rapid, ocean circulation-induced climate change. Here we present a detailed reconstruction of changing Rt in the late glacial period, from a high resolution marine sediment record north of 50° N. Stable isotope records and radiocarbon chronologies from cores collected in the St Kilda Basin, Hebridean shelf, containing highly-expanded late glacial records, will be used to assess the importance and controlling mechanisms of reservoir age variation in the NE Atlantic.

  19. Age-Related Macular Degeneration: Advances in Management and Diagnosis.

    PubMed

    Yonekawa, Yoshihiro; Miller, Joan W; Kim, Ivana K

    2015-01-01

    Age-related macular degeneration (AMD) is the most common cause of irreversible visual impairment in older populations in industrialized nations. AMD is a late-onset deterioration of photoreceptors and retinal pigment epithelium in the central retina caused by various environmental and genetic factors. Great strides in our understanding of AMD pathogenesis have been made in the past several decades, which have translated into revolutionary therapeutic agents in recent years. In this review, we describe the clinical and pathologic features of AMD and present an overview of current diagnosis and treatment strategies. PMID:26239130

  20. Effects of Vitreomacular Adhesion on Age-Related Macular Degeneration

    PubMed Central

    Kang, Eui Chun; Koh, Hyoung Jun

    2015-01-01

    Herein, we review the association between vitreomacular adhesion (VMA) and neovascular age-related macular degeneration (AMD). Meta-analyses have shown that eyes with neovascular AMD are twice as likely to have VMA as normal eyes. VMA in neovascular AMD may induce inflammation, macular traction, decrease in oxygenation, sequestering of vascular endothelial growth factor (VEGF), and other cytokines or may directly stimulate VEGF production. VMA may also interfere with the treatment effects of anti-VEGF therapy, which is the standard treatment for neovascular AMD, and releasing VMA can improve the treatment response to anti-VEGF treatment in neovascular AMD. We also reviewed currently available methods of relieving VMA. PMID:26425354

  1. Age-Related Macular Degeneration: Advances in Management and Diagnosis

    PubMed Central

    Yonekawa, Yoshihiro; Miller, Joan W.; Kim, Ivana K.

    2015-01-01

    Age-related macular degeneration (AMD) is the most common cause of irreversible visual impairment in older populations in industrialized nations. AMD is a late-onset deterioration of photoreceptors and retinal pigment epithelium in the central retina caused by various environmental and genetic factors. Great strides in our understanding of AMD pathogenesis have been made in the past several decades, which have translated into revolutionary therapeutic agents in recent years. In this review, we describe the clinical and pathologic features of AMD and present an overview of current diagnosis and treatment strategies. PMID:26239130

  2. Squalamine lactate for exudative age-related macular degeneration.

    PubMed

    Connolly, Brian; Desai, Avinash; Garcia, Charles A; Thomas, Edgar; Gast, Michael J

    2006-09-01

    Squalamine lactate inhibits angiogenesis by a long-lived, intracellular mechanism of action. The drug is taken up into activated endothelial cells through caveolae, small invaginations in the cellular membrane. Subsequently, the drug binds to and "chaperones" calmodulin to an intracellular membrane compartment and blocks angiogenesis at several levels. A series of basic investigations, preclinical studies, and human clinical trials have begun to establish the proof of concept, efficacy, and safety parameters for use of squalamine lactate as a therapeutic agent for exudative age-related macular degeneration and several types of malignancies. PMID:16935213

  3. Progressive Age-Related Changes Similar to Age-Related Macular Degeneration in a Transgenic Mouse Model

    PubMed Central

    Rakoczy, Piroska Elizabeth; Zhang, Dan; Robertson, Terry; Barnett, Nigel L.; Papadimitriou, John; Constable, Ian Jeffrey; Lai, Chooi-May

    2002-01-01

    Age-related macular degeneration (AMD) is the major cause of blindness in the developed world. Its pathomechanism is unknown and its late onset, complex genetics and strong environmental components have all hampered investigations. Here we demonstrate the development of an animal model for AMD that reproduces features associated with geographic atrophy; a transgenic mouse line (mcd/mcd) expressing a mutated form of cathepsin D that is enzymatically inactive thus impairing processing of phagocytosed photoreceptor outer segments in the retinal pigment epithelial (RPE) cells. Pigmentary changes indicating RPE cell atrophy and a decreased response to flash electroretinograms were observed in 11- to 12-month-old mcd/mcd mice. Histological studies showed RPE cell proliferation, photoreceptor degeneration, shortening of photoreceptor outer segments, and accumulation of immunoreactive photoreceptor breakdown products in the RPE cells. An accelerated photoreceptor cell death was detected in 12-month-old mcd/mcd mice. Transmission electron microscopy demonstrated presence of basal laminar and linear deposits that are considered to be the hallmarks of AMD. Small hard drusen associated with human age-related maculopathy were absent in the mcd/mcd mouse model at the ages analyzed. In summary, this model presents several features of AMD, thus providing a valuable tool for investigating the underlying biological processes and pathomechanism of AMD. PMID:12368224

  4. Relative Age Effect in UEFA Championship Soccer Players

    PubMed Central

    González-Víllora, Sixto; Pastor-Vicedo, Juan C.; Cordente, David

    2015-01-01

    Relative Age Effect (RAE) is the breakdown by both age grouping and dates of birth of athletes. In the past 20 years the existence of this effect has been shown with higher or smaller impact in multiple sports, including soccer. The purpose of this study was to identify the existence of RAE in European soccer players. The sample included 841 elite soccer players who were participants in the UEFA European Soccer Championship in different categories. The professional category (n = 368), U-19 (n = 144) and U-17 (n = 145) were in 2012, and U-21 was in 2011 (n = 184). The Kolmogorov-Smirnov test and the Levene test recommended the use of nonparametric statistics. The results obtained by the square test ( the Kruskal-Wallis test and Cohen’s effect sizes revealed the existence of RAE (χ2 = 17.829, p < 0.001; d = 0.30), with the size of their different effects depending on their category or qualifying round achieved by the national team and the existence of significance in the observed differences by category. Therefore, we could continue examining RAE which is present in elite soccer, and could be considered a factor that influences performance of the national teams tested. RAE was not evident in the professional teams analysed, however it was present in the three lower categories analysed (youth categories), with its influence being greater on younger age categories (U-17). PMID:26557207

  5. Nutritional Risk Factors for Age-Related Macular Degeneration

    PubMed Central

    Ersoy, Lebriz; Lechanteur, Yara T.; Hoyng, Carel B.; Kirchhof, Bernd; den Hollander, Anneke I.

    2014-01-01

    Purpose. To evaluate the role of nutritional factors, serum lipids, and lipoproteins in late age-related macular degeneration (late AMD). Methods. Intake of red meat, fruit, fish, vegetables, and alcohol, smoking status, and body mass index (BMI) were ascertained questionnaire-based in 1147 late AMD cases and 1773 controls from the European Genetic Database. Serum levels of lipids and lipoproteins were determined. The relationship between nutritional factors and late AMD was assessed using logistic regression. Based on multivariate analysis, area-under-the-curve (AUC) was calculated by receiver-operating-characteristics (ROC). Results. In a multivariate analysis, besides age and smoking, obesity (odds ratio (OR): 1.44, P = 0.014) and red meat intake (daily: OR: 2.34, P = 8.22 × 10−6; 2–6x/week: OR: 1.67, P = 7.98 × 10−5) were identified as risk factors for developing late AMD. Fruit intake showed a protective effect (daily: OR: 0.52, P = 0.005; 2–6x/week: OR: 0.58, P = 0.035). Serum lipid and lipoprotein levels showed no significant association with late AMD. ROC for nutritional factors, smoking, age, and BMI revealed an AUC of 0.781. Conclusion. Red meat intake and obesity were independently associated with increased risk for late AMD, whereas fruit intake was protective. A better understanding of nutritional risk factors is necessary for the prevention of AMD. PMID:25101280

  6. Age-related changes in angiogenesis in human dermis.

    PubMed

    Gunin, Andrei G; Petrov, Vadim V; Golubtzova, Natalia N; Vasilieva, Olga V; Kornilova, Natalia K

    2014-07-01

    Present research is aimed to examine the number of dermal blood vessels, vascular endothelial growth factor (VEGF), delta-like ligand 4(Dll4) and Jagged-1 (Jag-1) in dermal blood vessels of human from 20weeks of pregnancy to 85years old. Numbers and proliferative activity of dermal fibroblast-like cells were also examined. Blood vessels were viewed with immunohistochemical staining for von Willebrand factor or CD31. VEGF, Dll4, Jag-1, and proliferating cell nuclear antigen (PCNA) were detected immunohistochemically. Results showed that the numbers of fibroblast-like cells, PCNA positive fibroblast-like cells, von Willebrand factor positive or CD31 positive blood vessels in dermis are dramatically decreased with age. The intensity of immunohistochemical staining for VEGF or Jag-1 in blood vessels of dermis is increased from antenatal to deep old period. The degree of immunohistochemical staining of dermal blood vessels for Dll4 has gone up from 20-40weeks of pregnancy to early life period (0-20years), and further decreased below antenatal values. Age-related decrease in the number of dermal blood vessels is suggested to be due to an impairment of VEGF signaling and to be mediated by Dll4 and Jag-1. It may be supposed that diminishing in blood supply of dermis occurring with age is a cause of a decrease in the number and proliferative pool of dermal fibroblasts. PMID:24768823

  7. Factors related to choosing oral contraception at age 15.

    PubMed

    Kosunen, E; Laippala, P

    1996-12-01

    This report aims to identify factors which are related to use of oral contraceptives at an early age. A self-administered questionnaire was completed at schools in 1988 and 1992 in southern and western Finland (N = 1339). Sexually experienced girls (mean age 15.8 years) who had answered the question concerning their oral contraceptive use were included (N = 389). Logistic regression analysis was used to compare oral contraceptive users (N = 121) with the group of non-users. Total number of coital experiences was associated with oral contraceptive use: the odds ratio for those having at least 10 coital experiences was 6.30 compared with those with only one intercourse. The proportion was 73% among oral contraceptive users and 30% among non-users. Girls using oral contraceptives perceived more often (67%) that parents accept their sexual relationship (30% among non-users). Oral contraceptive users were less afraid of getting pregnant (9% compared with 31% among non-users) and felt more often that sex was very important in their life (31 and 13%, respectively). Other factors that entered the model were age at menarche, having a steady partner and frequency of disco visits. When a young girl asks for oral contraceptives, she is probably at true risk of pregnancy, and regular contraception should be considered both in view of effective prevention of pregnancies and sexually transmitted diseases. PMID:10163954

  8. Variations of Weight of Prostate Gland in Different Age Groups of Bangladeshi Cadaver.

    PubMed

    Epsi, E Z; Khalil, M; Mannan, S; Azam, M S; Ahmed, Z; Farjan, S; Kabir, A; Ara, I; Ajmery, S; Zaman, U K; Amin, S

    2016-07-01

    Now a days, benign prostatic hyperplasia and carcinoma of the prostate are the most common disorders in men. A cross sectional descriptive study was conducted in Department of Anatomy, Mymensingh Medical College, Mymensingh to find out the difference in weight of the prostate gland of Bangladeshi people in relation to age. The present study was performed on 67 postmortem human prostate gland collected from the morgue in the Department of Forensic Medicine, Mymensingh Medical College by non random purposive sampling technique. The specimens were collected from Bangladeshi cadaver of age ranging from 10 to 80 years. All the specimens were grouped into three categories - Group A (upto 18 years), Group B (19 to 45 years) and Group C (above 45 years) according to age. Dissection was performed according to standard autopsy techniques. The weight of the prostate gland were measured and recorded. The mean weight of the prostate gland was 10.13gm in Group A, 17.27gm in Group B and 22.50gm in Group C. Variance analysis shows that mean differences of weight of the prostate were highly significant among all age groups. The weight of prostate gland was found to increase with increased age. For statistical analysis, differences between age groups were analyzed by using students unpaired 't' test. The present study will help to increase the information pool on the weight of prostate gland of Bangladeshi people. PMID:27612887

  9. Individual variability in human blood metabolites identifies age-related differences

    PubMed Central

    Murakami, Itsuo; Takada, Junko; Kondoh, Hiroshi; Yanagida, Mitsuhiro

    2016-01-01

    Metabolites present in human blood document individual physiological states influenced by genetic, epigenetic, and lifestyle factors. Using high-resolution liquid chromatography-mass spectrometry (LC-MS), we performed nontargeted, quantitative metabolomics analysis in blood of 15 young (29 ± 4 y of age) and 15 elderly (81 ± 7 y of age) individuals. Coefficients of variation (CV = SD/mean) were obtained for 126 blood metabolites of all 30 donors. Fifty-five RBC-enriched metabolites, for which metabolomics studies have been scarce, are highlighted here. We found 14 blood compounds that show remarkable age-related increases or decreases; they include 1,5-anhydroglucitol, dimethyl-guanosine, acetyl-carnosine, carnosine, ophthalmic acid, UDP-acetyl-glucosamine, N-acetyl-arginine, N6-acetyl-lysine, pantothenate, citrulline, leucine, isoleucine, NAD+, and NADP+. Six of them are RBC-enriched, suggesting that RBC metabolomics is highly valuable for human aging research. Age differences are partly explained by a decrease in antioxidant production or increasing inefficiency of urea metabolism among the elderly. Pearson’s coefficients demonstrated that some age-related compounds are correlated, suggesting that aging affects them concomitantly. Although our CV values are mostly consistent with those CVs previously published, we here report previously unidentified CVs of 51 blood compounds. Compounds having moderate to high CV values (0.4–2.5) are often modified. Compounds having low CV values, such as ATP and glutathione, may be related to various diseases because their concentrations are strictly controlled, and changes in them would compromise health. Thus, human blood is a rich source of information about individual metabolic differences. PMID:27036001

  10. Individual variability in human blood metabolites identifies age-related differences.

    PubMed

    Chaleckis, Romanas; Murakami, Itsuo; Takada, Junko; Kondoh, Hiroshi; Yanagida, Mitsuhiro

    2016-04-19

    Metabolites present in human blood document individual physiological states influenced by genetic, epigenetic, and lifestyle factors. Using high-resolution liquid chromatography-mass spectrometry (LC-MS), we performed nontargeted, quantitative metabolomics analysis in blood of 15 young (29 ± 4 y of age) and 15 elderly (81 ± 7 y of age) individuals. Coefficients of variation (CV = SD/mean) were obtained for 126 blood metabolites of all 30 donors. Fifty-five RBC-enriched metabolites, for which metabolomics studies have been scarce, are highlighted here. We found 14 blood compounds that show remarkable age-related increases or decreases; they include 1,5-anhydroglucitol, dimethyl-guanosine, acetyl-carnosine, carnosine, ophthalmic acid, UDP-acetyl-glucosamine,N-acetyl-arginine,N6-acetyl-lysine, pantothenate, citrulline, leucine, isoleucine, NAD(+), and NADP(+) Six of them are RBC-enriched, suggesting that RBC metabolomics is highly valuable for human aging research. Age differences are partly explained by a decrease in antioxidant production or increasing inefficiency of urea metabolism among the elderly. Pearson's coefficients demonstrated that some age-related compounds are correlated, suggesting that aging affects them concomitantly. Although our CV values are mostly consistent with those CVs previously published, we here report previously unidentified CVs of 51 blood compounds. Compounds having moderate to high CV values (0.4-2.5) are often modified. Compounds having low CV values, such as ATP and glutathione, may be related to various diseases because their concentrations are strictly controlled, and changes in them would compromise health. Thus, human blood is a rich source of information about individual metabolic differences. PMID:27036001

  11. Cerebral microbleeds and age-related macular degeneration: the AGES-Reykjavik Study.

    PubMed

    Qiu, Chengxuan; Cotch, Mary Frances; Sigurdsson, Sigurdur; Eiriksdottir, Gudny; Jonasson, Fridbert; Klein, Ronald; Klein, Barbara E K; Harris, Tamara B; van Buchem, Mark A; Gudnason, Vilmundur; Launer, Lenore J

    2012-12-01

    We test the hypothesis that cerebral microbleeds (CMB) and age-related macular degeneration (AMD), both linked to amyloid-β deposition, are correlated. This study includes 4205 participants (mean age 76.2; 57.8% women) in the Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study (2002-2006). CMB were assessed from magnetic resonance images, and AMD was assessed using digital retinal images. Data were analyzed with multinomial logistic models controlling for major confounders. Evidence of CMB was detected in 476 persons (272 with strict lobar CMB and 204 with nonlobar CMB). AMD was detected in 1098 persons (869 with early AMD, 140 with exudative AMD, and 89 with pure geographic atrophy). Early and exudative AMD were not associated with CMB. The adjusted odds ratio of pure geographic atrophy was 1.62 (95% confidence interval 0.93-2.82, p = 0.089) for having any CMB, 1.43 (0.66-3.06, p = 0.363) for strict lobar CMB, and 1.85 (0.89-3.87, p = 0.100) for nonlobar CMB. This study provides no evidence that amyloid deposits in the brain and AMD are correlated. However, the suggestive association of geographic atrophy with CMB warrants further investigation. PMID:22382405

  12. Weight Gain in Pregnancy, Maternal Age and Gestational Age in Relation to Fetal Macrosomia

    PubMed Central

    Li, Yi; Liu, Qi-Fei; Zhang, Dan; Shen, Ying; Ye, Kui; Lai, Han-Lin; Wang, Hai-Qing; Hu, Chuan-Lai; Zhao, Qi-Hong

    2015-01-01

    To investigate the possible risk factors related to macrosomia. Pregnant women and their newborns (n = 1041) were recruited from a cohort study in Maternal and Child Care Center of Hefei from January 2011 to July 2012. Questionnaires were applied to collect the demographic data besides the medical records. Detailed health records of the entire pregnancy were obtained using retrospective study. Meanwhile the data of neonatal outcomes was prospectively tracked. Associations between exposure risk factors and macrosomia were analyzed using Pearson's chi squared test. Logistic regression models were used to assess the independent association between these potential predictors and macrosomia. The incidence of macrosomia of this cohort was 11.24% of which male: female = 2.55:1. Male incidence (8.07%) of macrosomia was higher than female (3.17%), p < 0.001. Body mass index (BMI) before pregnancy (pre-BMI), maternal height, parity were not independently associated with macrosomia; multiple logistic regression analysis indicated that macrosomia was mainly independently associated with weight gain in pregnancy (OR=1.14, 95% CI [1.10-1.19]), maternal age (OR = 1.09, 95% CI [1.03-1.15]) and gestational age (OR = 1.62, 95% CI [1.31-1.99]), respectively. Our findings indicate that weight gain in pregnancy, maternal age and gestational age should be considered as independent risk factors for macrosomia. PMID:25954731

  13. The relative roles of climate variations and human activities in vegetation change in North China

    NASA Astrophysics Data System (ADS)

    Sun, Yanling; Yang, Yanli; Zhang, Li; Wang, Zhongliang

    Using SPOT-VEGETATION Normal Difference Vegetation Index (SPOT/NDVI) data from 1998 to 2011 and climate data obtained from 223 weather stations in or near North China, vegetation variation characteristics within North China were analyzed. Vegetation variation characteristics under the influence of climate variations and human activities were distinguished through a residual analysis. Based on the results of that analysis, the relative roles of climate variations and human activities in vegetation variation were calculated. The results showed that NDVI observed by remote sensing (SPOT/NDVI) increased from 1998 to 2011. The relative roles of climate variations and human activities in vegetation increase were 30.82% and 69.18%, respectively, indicating that human activities played a major role. And observed NDVI showed an increasing trend for different land cover types overall. While NDVI increase in shrub was mainly caused by climate variations, NDVI increases in forest, grassland, farmland, deserts and urban were all primarily caused by human activities. For areas with increasing vegetation, as identified by remote sensing observations in North China, the relative roles of climate variations and human activities in vegetation change were calculated at 14.85% and 85.15% respectively, again indicating that human activities played an important role in vegetation increase. For areas of decreasing vegetation, as identified by remote sensing observations in North China, the relative roles of climate variations and human activities in vegetation change were calculated at 87.72% and 12.28% respectively, indicating that climate variations had large negative effects on vegetation condition. In addition, the relative roles of climate variations and human activities on vegetation variation have obvious spatial differences in North China. Human activities played a positive role in vegetation growth in North China. However, we cannot ignore the function of human destruction on

  14. A twin study on age-related macular degeneration.

    PubMed Central

    Meyers, S M

    1994-01-01

    A prospective twin study on age-related macular degeneration (AMD) recruited 83 monozygotic pairs, 28 dizygotic pairs, and one triplet set from 1986 through 1993. Zygosity was determined by genetic testing of red cell markers, HLA antigens, or specific DNA loci. There were no twin pairs in which I collected data on only one twin. To decrease ascertainment bias, after 1991 the recruitment notice did not mention AMD, and I did not ask about a history of eye disease before the eye examination. Because of this, twin pairs recruited from 1986 through 1991 were statistically analyzed separately from those after January 1, 1992. From 1986 through 1991, 23 twin pairs were recruited; 11 monozygotic and 2 dizygotic pairs had nonAMD retinal changes or no retinal abnormalities, 9 monozygotic pairs with AMD were all concordant, and 1 dizygotic pair was discordant for basal laminar drusen. The concordance rate of AMD did not differ significantly between monozygotic and dizygotic twin pairs (P = .10) for 1986 through 1991. In 1992 and 1993, 88 twin pairs and one triplet set were recruited; 49 monozygotic and 19 dizygotic pairs had nonAMD retinal changes or no retinal abnormalities, 14 monozygotic pairs with AMD were all concordant, and 2 of 7 dizygotic pairs were concordant for AMD. The nonidentical triplets (1 with and 2 without AMD) were categorized as one of the discordant dizygotic pairs in the statistical evaluation. In nontwin age-matched (within 2 or 5 years of age) or age- and sex-matched sibling pairs the concordance rate of AMD ranged from 16% to 25%. The concordance rate of AMD was significantly higher in monozygotic than in dizygotic twins (P = .001) for 1992 and 1993. The concordance rate was higher for monozygotic twin pairs recruited in 1992 and 1993 than in any of the four subsets of nontwin age-method or age- and sex-matched sibling pairs (P < .0001). Overall, from 1986 through 1993, 23 of 23 monozygotic and 2 of 8 dizygotic twin pairs were concordant for AMD

  15. Variation in Prolactin Is Related to Variation in Sexual Behavior and Contact Affiliation

    PubMed Central

    2015-01-01

    Prolactin is associated with both maternal and paternal care and appears important in developing a bond between parent and infant. In contrast with oxytocin, another hormone important in infant care, there is scant information on the role of prolactin in maintaining adult heterosexual relationships. We present here the first results demonstrating a relationship between prolactin levels and sexual and contact affiliation behavior in a pair-bonded species. We studied cotton-top tamarins, a socially-monogamous, cooperatively-breeding primate. We measured chronic urinary prolactin levels over a four week period to include the entire female ovulatory cycle and correlated prolactin levels in males and females with simultaneous measures of contact affiliation and sexual behavior. Current mothers who were no longer nursing displayed lower amounts of sexual behavior and proximity than non-breeding females and also had marginally lower levels of prolactin. The prolactin levels of males and females were similar within pairs, and variation in prolactin levels for both sexes was explained both by the amount of sexual behavior and contact affiliation. The results parallel a previous study that compared oxytocin levels with sociosexual behavior in the same species, and supports the hypothesis that both prolactin and oxytocin are involved in pair-bonding as well as in infant care. PMID:25799436

  16. 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

  17. dbAARD & AGP: A computational pipeline for the prediction of genes associated with age related disorders.

    PubMed

    Srivastava, Isha; Gahlot, Lokesh Kumar; Khurana, Pooja; Hasija, Yasha

    2016-04-01

    The atrocious behavioral and physiological shift with aging accelerate occurrence of deleterious disorders. Contemporary research is focused at uncovering the role of genetic associations in age-related disorders (ARDs). While the completion of the Human Genome Project and the HapMap project has generated huge amount of data on genetic variations; Genome-Wide Association Studies (GWAS) have identified genetic variations, essentially SNPs associated with several disorders including ARDs. However, a repository that houses all such ARD associations is lacking. The present work is aimed at filling this void. A database, dbAARD (database of Aging and Age Related Disorders) has been developed which hosts information on more than 3000 genetic variations significantly (p-value <0.05) associated with 51 ARDs. Furthermore, a machine learning based gene prediction tool AGP (Age Related Disorders Gene Prediction) has been constructed by employing rotation forest algorithm, to prioritize genes associated with ARDs. The tool achieved an overall accuracy in terms of precision 75%, recall 76%, F-measure 76% and AUC 0.85. Both the web resources have been made available online at http://genomeinformatics.dce.edu/dbAARD/ and http://genomeinformatics.dce.edu/AGP/ respectively for easy retrieval and usage by the scientific community. We believe that this work may facilitate the analysis of plethora of variants associated with ARDs and provide cues for deciphering the biology of aging. PMID:26836976

  18. Varying variation: the effects of within- versus across-feature differences on relational category learning

    PubMed Central

    Livins, Katherine A.; Spivey, Michael J.; Doumas, Leonidas A. A.

    2015-01-01

    Learning of feature-based categories is known to interact with feature-variation in a variety of ways, depending on the type of variation (e.g., Markman and Maddox, 2003). However, relational categories are distinct from feature-based categories in that they determine membership based on structural similarities. As a result, the way that they interact with feature variation is unclear. This paper explores both experimental and computational data and argues that, despite its reliance on structural factors, relational category-learning should still be affected by the type of feature variation present during the learning process. It specifically suggests that within-feature and across-feature variation should produce different learning trajectories due to a difference in representational cost. The paper then uses the DORA model (Doumas et al., 2008) to discuss how this account might function in a cognitive system before presenting an experiment aimed at testing this account. The experiment was a relational category-learning task and was run on human participants and then simulated in DORA. Both sets of results indicated that learning a relational category from a training set with a lower amount of variation is easier, but that learning from a training set with increased within-feature variation is significantly less challenging than learning from a set with increased across-feature variation. These results support the claim that, like feature-based category-learning, relational category-learning is sensitive to the type of feature variation in the training set. PMID:25709595

  19. 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…

  20. Retinal phagocytes in age-related macular degeneration

    PubMed Central

    Kim, Soo-Young

    2015-01-01

    Age-related macular degeneration (AMD) is the leading cause of blindness in industrial countries. Vision loss caused by AMD results from geographic atrophy (dry AMD) and/or choroidal neovascularization (wet AMD). Presently, the etiology and pathogenesis of AMD is not fully understood and there is no effective treatment. Oxidative stress in retinal pigment epithelial (RPE) cells is considered to be one of the major factors contributing to the pathogenesis of AMD. Also retinal glia, as scavengers, are deeply related with diseases and could play a role. Therefore, therapeutic approaches for microglia and Müller glia, as well as RPE, may lead to new strategies for AMD treatment. This review summarizes the pathological findings observed in RPE cells, microglia and Müller glia of AMD murine models. PMID:26052551

  1. The Neural Consequences of Age-Related Hearing Loss.

    PubMed

    Peelle, Jonathan E; Wingfield, Arthur

    2016-07-01

    During hearing, acoustic signals travel up the ascending auditory pathway from the cochlea to auditory cortex; efferent connections provide descending feedback. In human listeners, although auditory and cognitive processing have sometimes been viewed as separate domains, a growing body of work suggests they are intimately coupled. Here, we review the effects of hearing loss on neural systems supporting spoken language comprehension, beginning with age-related physiological decline. We suggest that listeners recruit domain general executive systems to maintain successful communication when the auditory signal is degraded, but that this compensatory processing has behavioral consequences: even relatively mild levels of hearing loss can lead to cascading cognitive effects that impact perception, comprehension, and memory, leading to increased listening effort during speech comprehension. PMID:27262177

  2. The Relative Age Effect and Its Influence on Academic Performance

    PubMed Central

    Navarro, Juan-José; García-Rubio, Javier; Olivares, Pedro R.

    2015-01-01

    Introduction and Purpose The policy of school organisation for grouping students in the same academic year is based on date of birth. The differences in the experiences and maturation of older students involve a relatively better performance in academic settings, which is known as the relative age effect (RAE). This effect is more important the younger the student is. The goal of this study is to identify the connections of influence that RAE, socioeconomic status (SES), and type of institution have on academic performance in a school population of eighth graders. Methods The study is based on a population-based, representative sample of 15,234 8th graders (50.4% female; average age = 13.61 years) in the 2011 National System of Quality Assessment in Education Survey (SIMCE) from Chile. The SIMCE for global academic performance consists of 4 tests: reading, mathematics, social studies, and science. All tests consist of multiple-choice and closed questions. In addition, in order to have the information of general academic performance, an extra variable expressing the average score of each student was created. Also, the SIMCE includes additional variables for the evaluation process such as SES or type of school. Students were assigned to one of five age groups in terms of date of birth (G1, G2, G3, G4, and G5), in which students belonging to G1 are the oldest and students belonging to G5 are the youngest. Results The results achieved in the structural equation modelling indicate a good global fit. Individual relationships show significant effects of the three variables observed on academic performance, although SES received the highest values. The influence of RAE took place both in the full sample and sub-samples composed according to the SES and academic performance, showing higher values for students with lower scores. Although the influence of RAE decreases when SES is controlled, its effect is still significant and contributes to additionally explain the

  3. Genetic risk factors and age-related macular degeneration (AMD)

    PubMed Central

    Mousavi, Maryam; Armstrong, Richard A.

    2013-01-01

    Age related macular degeneration (AMD) is the leading cause of blindness in individuals older than 65 years of age. It is a multifactorial disorder and identification of risk factors enables individuals to make lifestyle choices that may reduce the risk of disease. Collaboration between geneticists, ophthalmologists, and optometrists suggests that genetic risk factors play a more significant role in AMD than previously thought. The most important genes are associated with immune system modulation and the complement system, e.g., complement factor H (CFH), factor B (CFB), factor C3, and serpin peptidase inhibitor (SERPING1). Genes associated with membrane transport, e.g., ATP-binding cassette protein (ABCR) and voltage-dependent calcium channel gamma 3 (CACNG3), the vascular system, e.g., fibroblast growth factor 2 (FGF2), fibulin-5, lysyl oxidase-like gene (LOXL1) and selectin-P (SELP), and with lipid metabolism, e.g., apolipoprotein E (APOE) and hepatic lipase (LIPC) have also been implicated. In addition, several other genes exhibit some statistical association with AMD, e.g., age-related maculopathy susceptibility protein 2 (ARMS2) and DNA excision repair protein gene (ERCC6) but more research is needed to establish their significance. Modifiable risk factors for AMD should be discussed with patients whose lifestyle and/or family history place them in an increased risk category. Furthermore, calculation of AMD risk using current models should be recommended as a tool for patient education. It is likely that AMD management in future will be increasingly influenced by assessment of genetic risk as such screening methods become more widely available.

  4. Inflammation and its role in age-related macular degeneration.

    PubMed

    Kauppinen, Anu; Paterno, Jussi J; Blasiak, Janusz; Salminen, Antero; Kaarniranta, Kai

    2016-05-01

    Inflammation is a cellular response to factors that challenge the homeostasis of cells and tissues. Cell-associated and soluble pattern-recognition receptors, e.g. Toll-like receptors, inflammasome receptors, and complement components initiate complex cellular cascades by recognizing or sensing different pathogen and damage-associated molecular patterns, respectively. Cytokines and chemokines represent alarm messages for leukocytes and once activated, these cells travel long distances to targeted inflamed tissues. Although it is a crucial survival mechanism, prolonged inflammation is detrimental and participates in numerous chronic age-related diseases. This article will review the onset of inflammation and link its functions to the pathogenesis of age-related macular degeneration (AMD), which is the leading cause of severe vision loss in aged individuals in the developed countries. In this progressive disease, degeneration of the retinal pigment epithelium (RPE) results in the death of photoreceptors, leading to a loss of central vision. The RPE is prone to oxidative stress, a factor that together with deteriorating functionality, e.g. decreased intracellular recycling and degradation due to attenuated heterophagy/autophagy, induces inflammation. In the early phases, accumulation of intracellular lipofuscin in the RPE and extracellular drusen between RPE cells and Bruch's membrane can be clinically detected. Subsequently, in dry (atrophic) AMD there is geographic atrophy with discrete areas of RPE loss whereas in the wet (exudative) form there is neovascularization penetrating from the choroid to retinal layers. Elevations in levels of local and systemic biomarkers indicate that chronic inflammation is involved in the pathogenesis of both disease forms. PMID:26852158

  5. Age-related vascular stiffening: causes and consequences

    PubMed Central

    Kohn, Julie C.; Lampi, Marsha C.; Reinhart-King, Cynthia A.

    2015-01-01

    Arterial stiffening occurs with age and is closely associated with the progression of cardiovascular disease. Stiffening is most often studied at the level of the whole vessel because increased stiffness of the large arteries can impose increased strain on the heart leading to heart failure. Interestingly, however, recent evidence suggests that the impact of increased vessel stiffening extends beyond the tissue scale and can also have deleterious microscale effects on cellular function. Altered extracellular matrix (ECM) architecture has been recognized as a key component of the pre-atherogenic state. Here, the underlying causes of age-related vessel stiffening are discussed, focusing on age-related crosslinking of the ECM proteins as well as through increased matrix deposition. Methods to measure vessel stiffening at both the macro- and microscale are described, spanning from the pulse wave velocity measurements performed clinically to microscale measurements performed largely in research laboratories. Additionally, recent work investigating how arterial stiffness and the changes in the ECM associated with stiffening contributed to endothelial dysfunction will be reviewed. We will highlight how changes in ECM protein composition contribute to atherosclerosis in the vessel wall. Lastly, we will discuss very recent work that demonstrates endothelial cells (ECs) are mechano-sensitive to arterial stiffening, where changes in stiffness can directly impact EC health. Overall, recent studies suggest that stiffening is an important clinical target not only because of potential deleterious effects on the heart but also because it promotes cellular level dysfunction in the vessel wall, contributing to a pathological atherosclerotic state. PMID:25926844

  6. Age-Related Macular Degeneration: A Scientometric Analysis

    PubMed Central

    Ramin, Shahrokh; Soheilian, Masoud; Habibi, Gholamreza; Ghazavi, Roghayeh; Gharebaghi, Reza; Heidary, Fatemeh

    2015-01-01

    Age-related macular degeneration (ARMD) is a major cause of central blindness among working aged adults across the world. Systematic research planning on any subject, including ARMD is in need of solid data regarding previous efforts in this field and to identify the gaps in the research. This study aimed to elucidate the most important trends, directions, and gap in this subject. The data extracted from the Institute for Scientific Information were used to perform a bibliometric analysis of the scientific productions (1993–2013) about ARMD. Specific parameters related to ARMD were analyzed to obtain a view of the topic’s structure, history, and document relationships. Additionally, the trends and authors in the most influential publications were analyzed. The number of articles in this field was found constantly increasing. Most highly cited articles addressed genetic epidemiology and clinical research topics in this field. During the past 3 years, there has been a trend toward biomarker research. Through performing the first scientometric survey on ARMD research, we analyzed the characteristics of papers and the trends in scientific production. We also identified some of the critical gaps in the current research efforts that would help in large-scale research strategic planning. PMID:26060829

  7. Age-Related Changes in Demand-Withdraw Communication Behaviors.

    PubMed

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

    2013-08-01

    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

  8. Fertility preservation for age-related fertility decline.

    PubMed

    Stoop, Dominic; Cobo, Ana; Silber, Sherman

    2014-10-01

    Cryopreservation of eggs or ovarian tissue to preserve fertility for patients with cancer has been studied since 1994 with R G Gosden's paper describing restoration of fertility in oophorectomised sheep, and for decades previously by others in smaller mammals. Clinically this approach has shown great success. Many healthy children have been born from eggs cryopreserved with the Kuwayama egg vitrification technique for non-medical (social) indications, but until now very few patients with cancer have achieved pregnancy with cryopreserved eggs. Often, oncologists do not wish to delay cancer treatment while the patient goes through multiple ovarian stimulation cycles to retrieve eggs, and the patient can only start using the oocytes after full recovery from cancer. Ovarian stimulation and egg retrieval is not a barrier for patients without cancer who wish to delay childbearing, which makes oocyte cryopreservation increasingly popular to overcome an age-related decline in fertility. Cryopreservation of ovarian tissue is an option if egg cryopreservation is ruled out. More than 35 babies have been born so far with cryopreserved ovarian tissue in patients with cancer who have had a complete return of hormonal function, and fertility to baseline. Both egg and ovarian tissue cryopreservation might be ready for application to the preservation of fertility not only in patients with cancer but also in countering the increasing incidence of age-related decline in female fertility. PMID:25283572

  9. Flavonoids and Age Related Disease: Risk, benefits and critical windows

    PubMed Central

    Prasain, JK; Carlson, SH; Wyss, JM

    2010-01-01

    Plant derived products are consumed by a large percentage of the population to prevent, delay and ameliorate disease burden; however, relatively little is known about the efficacy, safety and underlying mechanisms of these traditional health products, especially when taken in concert with pharmaceutical agents. The flavonoids are a group of plant metabolites that are common in the diet and appear to provide some health benefits. While flavonoids are primarily derived from soy, many are found in fruits, nuts and more exotic sources, e.g., kudzu. Perhaps the strongest evidence for the benefits of flavonoids in diseases of aging relates to their effect on components of the metabolic syndrome. Flavonoids from soy, grape seed, kudzu and other sources all lower arterial pressure in hypertensive animal models and in a limited number of tests in humans. They also decrease the plasma concentration of lipids and buffer plasma glucose. The underlying mechanisms appear to include antioxidant actions, central nervous system effects, gut transport alterations, fatty acid sequestration and processing, PPAR activation and increases in insulin sensitivity. In animal models of disease, dietary flavonoids also demonstrate a protective effect against cognitive decline, cancer and metabolic disease. However, research also indicates that the flavonoids can be detrimental in some settings and, therefore, are not universally safe. Thus, as the population ages, it is important to determine the impact of these agents on prevention/attenuation of disease, including optimal exposure (intake, timing/duration) and potential contraindications. PMID:20181448

  10. Current therapeutic developments in atrophic age-related macular degeneration.

    PubMed

    Hanus, Jakub; Zhao, Fangkun; Wang, Shusheng

    2016-01-01

    Age-related macular degeneration (AMD), a degenerative disorder of the central retina, is the leading cause of irreversible blindness in the elderly. The underlying mechanism of the advanced form of dry AMD, also named geographic atrophy (GA) or atrophic AMD, remains unclear. Consequently, no cure is available for dry AMD or GA. The only prevention option currently available is the Age-Related Eye Disease Study (AREDS) formulation, which has been demonstrated to slow down the progression of dry AMD. This review summarises recent advances in therapy for dry AMD and GA. Building on the new understanding of the disease and recent technological breakthroughs, numerous ongoing clinical trials have the goal of meeting the need to cure AMD. Therapeutic agents are being developed to target the key features of the disease, including inhibiting the complement pathway and other inflammatory pathways, reducing oxidative stress and protecting retinal pigment epithelial (RPE) cells, inhibiting lipofuscin and visual cycle, regenerating RPE cells from stem cells and restoring choroidal blood flow. Some of these therapeutic options, especially the stem cell-based therapy, hold great promise, which brings great hope for this devastating blinding disease. PMID:26553922

  11. 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

  12. Current Therapeutic Development for Atrophic Age-related Macular Degeneration

    PubMed Central

    Hanus, Jakub; Zhao, Fangkun; Wang, Shusheng

    2016-01-01

    Age-related macular degeneration (AMD), a degenerative disorder of the central retina, is the leading cause of irreversible blindness in the elderly. The underlying mechanism of the advanced form of dry AMD, also named geographic atrophy (GA) or atrophic AMD, remains unclear. Consequently, no cure is available for dry AMD or GA. The only prevention option currently available is the Age Related Eye Disease Study (AREDS) formulation which has been demonstrated to slow down the progression of dry AMD. This review summarizes recent advances in therapy for dry AMD and GA. Building on the new understanding of the disease and recent technological breakthroughs, numerous ongoing clinical trials have the goal of meeting the need to cure AMD. Therapeutic agents are being developed to target the key features of the disease, including inhibiting the complement pathway and other inflammatory pathways, reducing oxidative stress and protecting retinal pigment epithelial (RPE) cells, inhibiting lipofuscin and visual cycle, regenerating RPE cells from stem cells and restoring choroidal blood flow. Some of these therapeutic options, especially the stem-cell based therapy, hold great promise, which brings great hope for this devastating blinding disease. PMID:26553922

  13. Historical Variation in Young Adult Binge Drinking Trajectories and Its Link to Historical Variation in Social Roles and Minimum Legal Drinking Age

    ERIC Educational Resources Information Center

    Jager, Justin; Keyes, Katherine M.; Schulenberg, John E.

    2015-01-01

    This study examines historical variation in age 18 to 26 binge drinking trajectories, focusing on differences in both levels of use and rates of change (growth) across cohorts of young adults over 3 decades. As part of the national Monitoring the Future Study, over 64,000 youths from the high school classes of 1976 to 2004 were surveyed at…

  14. Age-dependent variation of the Gradient Index profile in human crystalline lenses

    PubMed Central

    de Castro, A.; Siedlecki, D.; Borja, David; Uhlhorn, Stephen; Parel, Jean-Marie; Manns, Fabrice; Marcos, S.

    2011-01-01

    Purpose To reconstruct the gradient index (GRIN) profile of human crystalline lenses ex-vivo using Optical Coherence Tomography (OCT) imaging with an optimization technique and to study the dependence of the GRIN profile with age. Methods Cross-sectional images of nine isolated human crystalline lenses with ages ranging from 6 to 72 (post mortem time 1 to 4 days) were obtained using a custom-made OCT system. Lenses were extracted from whole cadaver globes and placed in a measurement chamber filled with preservation medium (DMEM). Lenses were imaged with the anterior surface up and then flipped over and imaged again, to obtain posterior lens surface profiles both undistorted and distorted by the refraction through the anterior crystalline lens and GRIN. The GRIN distribution of the lens was described with three variables by means of power function, with variables being the nucleus and surface index, and a power coefficient that describes the decay of the refractive index from the nucleus to the surface. An optimization method was used to search for the parameters that produced the best match of the distorted posterior surface. Results The distorted surface was simulated with accuracy around the resolution of the OCT system (under 15 µm). The reconstructed refractive index values ranged from 1.356 to 1.388 for the surface, and from 1.396 to 1.434 for the nucleus. The power coefficient ranged between 3 and 18. The power coefficient increased significantly with age, at a rate of 0.24 per year. Conclusion Optical Coherence Tomography allowed optical, non-invasive measurement of the 2-D gradient index profile of the isolated human crystalline lens ex vivo. The age-dependent variation of the changes is consistent with previous data using magnetic resonance imaging, and the progressive formation of a refractive index plateau. PMID:22865954

  15. Age-dependent variation of the gradient index profile in human crystalline lenses

    NASA Astrophysics Data System (ADS)

    de Castro, Alberto; Siedlecki, Damian; Borja, David; Uhlhorn, Stephen; Parel, Jean-Marie; Manns, Fabrice; Marcos, Susana

    2011-11-01

    An investigation was carried out with the aim of reconstructing the gradient index (GRIN) profile of human crystalline lenses ex-vivo using optical coherence tomography (OCT) imaging with an optimization technique and to study the dependence of the GRIN profile with age. Cross-sectional images of nine isolated human crystalline lenses with ages ranging from 6 to 72 (post-mortem time 1 to 4 days) were obtained using a custom-made OCT system. Lenses were extracted from whole cadaver globes and placed in a measurement chamber filled with preservation medium (DMEM). Lenses were imaged with the anterior surface up and then flipped over and imaged again, to obtain posterior lens surface profiles both undistorted and distorted by the refraction through the anterior crystalline lens and GRIN. The GRIN distribution of the lens was described with three variables by means of power function, with variables being the nucleus and surface index, and a power coefficient that describes the decay of the refractive index from the nucleus to the surface. An optimization method was used to search for the parameters that produced the best match of the distorted posterior surface. The distorted surface was simulated with accuracy around the resolution of the OCT system (under 15 µm). The reconstructed refractive index values ranged from 1.356 to 1.388 for the surface, and from 1.396 to 1.434 for the nucleus. The power coefficient ranged between 3 and 18. The power coefficient increased significantly with age, at a rate of 0.24 per year. Optical coherence tomography allowed optical, non-invasive measurement of the 2D gradient index profile of the isolated human crystalline lens ex vivo. The age-dependent variation of the changes is consistent with previous data using magnetic resonance imaging, and the progressive formation of a refractive index plateau.

  16. Reproductive patterns result from age-related sensitivity to resources and reproductive costs in a mammalian carnivore.

    PubMed

    Rauset, Geir Rune; Low, Matthew; Persson, Jens

    2015-12-01

    Although the effects of individual age, resource availability, and reproductive costs have been extensively studied to understand the causes of variation in reproductive output, there are almost no studies showing how these factors interact in explaining this variation. To examine this interaction, we used longitudinal demographic data from an 18-year study of 53 breeding female wolverines (Gulo gulo), and corresponding environmental data from their individual home ranges. Females showed a typical age-related pattern in reproductive output, with an initial increase followed by a senescent decline in later years. This pattern was largely driven by four processes: (1) physiological/behavioral maturation between ages two and three; (2) age-related differences in the costs of reproduction resulting in an initial increase, and then a declining probability of breeding two years in a row as individuals aged; (3) resource availability (reindeer [Rangifer tarandus] carcass abundance; mostly Eurasian lynx [Lynx lynx] kills) in the months preceding parturition, which influenced the probability of having cubs, but only for individuals that had successfully bred in the previous year; and (4) resource availability also influenced the cost of reproduction in an age-dependent manner, as prime age females that had bred in the previous year were more responsive to resource availability than those at other ages. This study demonstrates that by examining how drivers of reproductive variation interact, we can get a much clearer understanding of the mechanisms responsible for age-related patterns of reproduction. This has implications not only for general ecological theory, but will also allow better predictions of population resnonses to environmental changes or management based on a population's age-structure. PMID:26909422

  17. Progress and Prospects in Human Genetic Research into Age-Related Hearing Impairment

    PubMed Central

    Sugiura, Saiko; Ueda, Hiromi; Nakashima, Tsutomu

    2014-01-01

    Age-related hearing impairment (ARHI) is a complex, multifactorial disorder that is attributable to confounding intrinsic and extrinsic factors. The degree of impairment shows substantial variation between individuals, as is also observed in the senescence of other functions. This individual variation would seem to refute the stereotypical view that hearing deterioration with age is inevitable and may indicate that there is ample scope for preventive intervention. Genetic predisposition could account for a sizable proportion of interindividual variation. Over the past decade or so, tremendous progress has been made through research into the genetics of various forms of hearing impairment, including ARHI and our knowledge of the complex mechanisms of auditory function has increased substantially. Here, we give an overview of recent investigations aimed at identifying the genetic risk factors involved in ARHI and of what we currently know about its pathophysiology. This review is divided into the following sections: (i) genes causing monogenic hearing impairment with phenotypic similarities to ARHI; (ii) genes involved in oxidative stress, biologic stress responses, and mitochondrial dysfunction; and (iii) candidate genes for senescence, other geriatric diseases, and neurodegeneration. Progress and prospects in genetic research are discussed. PMID:25140308

  18. Application of terahertz absorption spectroscopy to evaluation of aging variation of medicine.

    PubMed

    Kawase, Masaya; Saito, Tadashi; Ogawa, Masafumi; Uejima, Hideki; Hatsuda, Yasutoshi; Kawanishi, Sonoyo; Hirotani, Yoshihiko; Myotoku, Michiaki; Ikeda, Kenji; Konishi, Hiroki; Iga, Ikumi; Yamakawa, Junji; Nishizawa, Seizi; Yamamoto, Kohji; Tani, Masahiko

    2011-01-01

    The absorption spectra of three kinds of medicines both before and after the expiration date: Amlodin OD(®) (5 mg), Basen OD(®) (0.2 mg) and Gaster D(®) (10 mg) have been measured by terahertz time domain spectroscopy (THz-TDS). All the medicines show some differences in the THz absorption spectra between medicines before and after the expiration dates. X-Ray powder diffraction (XRD) studies of all medicines suggest that the polymorph of the main effective compound is not changed before and after the expiration date. Therefore, the differences in the THz spectra between medicines before and after the expiration dates arise from aging variation of diluting agents and/or from modifications of intermolecular interaction between the effective compounds and diluting agents. PMID:21321447

  19. Age-Related Differences in Judgments of Inappropriate Behavior are Related to Humor Style Preferences

    PubMed Central

    Stanley, Jennifer Tehan; Lohani, Monika; Isaacowitz, Derek M.

    2014-01-01

    Identifying social gaffes is important for maintaining relationships. Older adults are less able than young to discriminate between socially appropriate and inappropriate behavior in video clips. One open question is how these social appropriateness ratings relate to potential age differences in the perception of what is actually funny or not. In the present study, young, middle-aged, and older adults were equally able to discriminate between appropriate and inappropriate social behavior in a diverse set of clips relevant to both age groups. However, young and middle-aged adults rated the gaffe clips as funnier than control clips and young adults smiled more during the inappropriate clips than the control clips. Older adults did not show this pattern, suggesting that they did not find the inappropriate clips funny. Additionally, young adults endorsed a more aggressive humor style than middle-aged and older adults and aggressive humor style endorsement mediated age differences in social appropriateness ratings. Results are discussed in terms of possible mechanisms such as cohort differences in humor and developmental prioritization of certain humor styles, as well as the importance of investigating age differences in both abilities and preferences. PMID:25244473

  20. Variation of diabetes mellitus prevalence in general practice and its relation to deprivation.

    PubMed

    Meadows, P

    1995-08-01

    This is an observational study to compare age standardized diabetes prevalences and relate these to socio-economic measures of deprivation. It includes data from eight general (family) practices in the Bristol, UK, area with no ethnic minorities affecting diabetes prevalence. A total population of 71 599 was covered, including 181 Type 1 and 901 Type 2 diabetic patients, 91 of whom were controlled with insulin, 499 with oral hypoglycaemics, and 311 with diet alone. Actual Type 1 and Type 2 diabetes prevalences were standardized to what they would be if each practice had the UK national age profile. Total standardized diabetes prevalence varied from 1.31% to 2.51% (p < 0.001) and Type 2 diabetes prevalence from 0.97% to 2.29% (p < 0.001). There was no significant variation in the prevalence of Type 1 diabetes. The Spearman rank correlation coefficient indicated a significant association between standardized diabetes prevalence and two measures, the Jarman and Townsend indices, of deprivation in the electoral ward where each practice was situated. Total standardized diabetes prevalence was significantly correlated with each of the Jarman and Townsend indices (r = 0.76, p < 0.05). Standardized Type 2 diabetes prevalence was similarly significantly correlated to each deprivation index (rs = 0.74, p < 0.05). Type 2 diabetes prevalence is affected by socio-economic factors with implications for health targets and capitation based budgets. PMID:7587009

  1. Sex-related variation in human behavior and the brain

    PubMed Central

    Hines, Melissa

    2010-01-01

    Male and female fetuses differ in testosterone concentrations beginning as early as week 8 of gestation. This early hormone difference exerts permanent influences on brain development and behavior. Contemporary research shows that hormones are particularly important for the development of sex-typical childhood behavior, including toy choices, which until recently were thought to result solely from sociocultural influences. Prenatal testosterone exposure also appears to influence sexual orientation and gender identity, as well as some, but not all, sex-related cognitive, motor and personality characteristics. Neural mechanisms responsible for these hormone-induced behavioral outcomes are beginning to be identified, and current evidence suggests involvement of the hypothalamus and amygdala, as well as interhemispheric connectivity, and cortical areas involved in visual processing. PMID:20724210

  2. The influence of cone age on the relative longevity of Banksia seeds

    PubMed Central

    Crawford, A. D.; Plummer, J. A.; Probert, R. J.; Steadman, K. J.

    2011-01-01

    Background and Aims Serotiny is common in the genus Banksia, so any seed collection is likely to be comprised of seeds that were produced in many different years. This study aimed to determine the impact of cone age and degree of serotiny on longevity in ex situ storage. Methods Cones of identifiable age classes were collected from three species of Banksia. Seeds were extracted from cones and the degree of serotiny calculated. An estimate of initial viability (Ki), the time for viability to fall by one probit (σ) and the relative longevity of seeds (p50) for each species and cone age class was determined using a comparative longevity test (50 °C, 63 % relative humidity). Key Results The degree of serotiny ranged from moderate (7·9) for Banksia attenuata to strong (40·4) for B. hookeriana. Survival curves for all seed age classes within each species could be described by regressions with a common slope (1/σ), but with different values for Ki. The time taken for viability to fall by one probit (σ) could be described by a common value (29·1 d) for all three species. Conclusions Differences in seed longevity between cone age classes and species was related to variation in initial viability (Ki) rather than to differences in σ. While targeting the youngest mature seed cohort on a plant will maximize the viability of seeds collected, a wide range of age classes should be collected (but stored as separate cohorts if possible) for quality conservation/restoration seed collections where genetic diversity is important. PMID:21123185

  3. Relating Age Change and Behavior to Job Requirements.

    ERIC Educational Resources Information Center

    Schaie, K. Warner

    The Age Discrimination in Employment Act has been amended to outlaw mandatory retirement at any age. However, the act permits employers to impose a specific retirement age if there is a bona fide occupational qualification (BFOQ) which cannot be met by all or most individuals. Imposition of BFOQ mandatory retirement ages by employers has led to…

  4. Spatial and temporal variation in age and growth in juvenile Loligo forbesi and relationships with recruitment in the English Channel and Scottish waters

    NASA Astrophysics Data System (ADS)

    Challier, Laurence; Pierce, Graham J.; Robin, Jean-Paul

    2006-04-01

    In many cephalopod stocks, resource abundance and fishing yields depend on the recruitment of the annual cohort. Loliginid squids such as Loligo forbesi are present in the English Channel and in Scottish waters. Variation in age and growth in juvenile Loligo forbesi of these two areas was investigated at the spatial and temporal scale, and inter-annual differences in growth were related to recruitment variation to test density dependence in squid growth in both populations. Spatial and temporal differences in growth were analysed in five cohorts that showed marked differences in recruitment abundance. Biological sampling showed that recruitment occurred in late autumn and spring in Scottish waters and in summer in the English Channel. In both fishing seasons, monthly samples collected at fish markets were analysed and ages of juveniles (mantle length < 200 mm) were determined using daily statolith growth increments. Age determination indicated that recruits were older than previously thought (about 8 to 11 months). Back-calculated hatching dates were used to estimate growth variation during the pre-recruitment stage. Exponential growth models adequately described size-at-age data. Linear modelling demonstrated inter-annual and spatial significant differences in growth rates. Influence of the hatching month (within or between cohorts) on growth was detected. To improve our understanding of recruitment variability, this study addresses the question: Does early growth vary in relation with recruitment? Available recruitment estimates appeared to be related to annual growth rates; density dependence in squid growth is suggested for the English Channel population.

  5. Frequency variations of discrete cranial traits in major human populations. IV. Vessel and nerve related variations

    PubMed Central

    HANIHARA, TSUNEHIKO; ISHIDA, HAJIME

    2001-01-01

    This concludes a series of descriptive statistical reports on discrete cranial traits in 81 human populations from around the world. Four variants classified as vessel and nerve related characters were investigated: patent condylar canal; supraorbital foramen; accessory infraorbital foramen; and accessory mental foramen. A significant asymmetric occurrence without any side preference was detected for the accessory mental foramen. Significant intertrait associations were found between the accessory infraorbital and supraorbital foramina in the panPacific region and Subsaharan African samples. The intertrait associations between the accessory infraorbital foramen and some traits classified as hypostotic were found mainly in the samples from the western part of the Old World, and those as hyperostotic traits in the samples from eastern Asian and the related population samples. With a few exceptions, the occurrence of a patent condylar canal and a supraorbital foramen was predominant in females, but the accessory infraorbital and accessory mental foramina were predominant in males. The frequency distributions of the traits showed interregional clinality and intraregional discontinuity. A temporal trend was found in the Northeast Asian region in the frequencies of the accessory infraorbital and accessory mental foramina. The diversity of modern human discrete cranial traits may at least in part be attributable to differential retention or intensification from an ancestral pattern. PMID:11554505

  6. Familial Risk of Early Suicide: Variations by Age and Sex of Children and Parents

    ERIC Educational Resources Information Center

    Garssen, Joop; Deerenberg, Ingeborg; Mackenbach, Johan P.; Kerkhof, Ad; Kunst, Anton E.

    2011-01-01

    To determine familial risk of early suicide, data on cause of death of all Dutch residents aged 20-55 years who died between 1995 and 2001 were linked to data of their parents. Men whose father died by suicide had a higher odds of suicide themselves, relative to men whose father died of other causes (Odds Ratio (OR): 2.5; 95% confidence interval:…

  7. Ocular Surface Temperature in Age-Related Macular Degeneration

    PubMed Central

    Sodi, Andrea; Giacomelli, Giovanni; Corvi, Andrea; Menchini, Ugo

    2014-01-01

    Background. The aim of this study is to investigate the ocular thermographic profiles in age-related macular degeneration (AMD) eyes and age-matched controls to detect possible hemodynamic abnormalities, which could be involved in the pathogenesis of the disease. Methods. 32 eyes with early AMD, 37 eyes with atrophic AMD, 30 eyes affected by untreated neovascular AMD, and 43 eyes with fibrotic AMD were included. The control group consisted of 44 healthy eyes. Exclusion criteria were represented by any other ocular diseases other than AMD, tear film abnormalities, systemic cardiovascular abnormalities, diabetes mellitus, and a body temperature higher than 37.5°C. A total of 186 eyes without pupil dilation were investigated by infrared thermography (FLIR A320). The ocular surface temperature (OST) of three ocular points was calculated by means of an image processing technique from the infrared images. Two-sample t-test and one-way analysis of variance (ANOVA) test were used for statistical analyses. Results. ANOVA analyses showed no significant differences among AMD groups (P value >0.272). OST in AMD patients was significantly lower than in controls (P > 0.05). Conclusions. Considering the possible relationship between ocular blood flow and OST, these findings might support the central role of ischemia in the pathogenesis of AMD. PMID:25436140

  8. Age-related synthesis of glucocorticoids in thymocytes

    SciTech Connect

    Qiao Shengjun Chen Liying; Okret, Sam; Jondal, Mikael

    2008-10-01

    Glucocorticoids (GCs) are primarily synthesized in the adrenal glands but an ectopic production has also been reported in the brain, the gastrointestinal tract and in thymic epithelial cells (TEC). Here we show that thymocytes express genes encoding for all enzymes required for de novo GC synthesis and produce the hormone as demonstrated by both a GC specific reporter assay and a corticosterone specific ELISA assay. Interestingly, GC synthesis is detectable in cells from young mice (4 weeks) and thereafter increases during aging (14-22 weeks) together with an increased gene expression of the rate-limiting enzymes StAR and CYP11A1. Hormone production occurred at a thymocyte differentiation stage characterized by being double positive for the CD4 and CD8 surface markers but was found to be unrelated to CD69 expression, a marker for thymocytes undergoing positive selection. No GC synthesis was found in resting or anti-CD3 activated CD4 and CD8 positive T cells isolated from the spleen. Thymocyte-derived GC had an anti-proliferative effect on a GR-transfected cell line and induced apoptosis in thymocytes. The age- and differentiation stage-related GC synthesis in thymocytes may play a role in the involution process that the thymus gland undergoes.

  9. Angiofluorographic aspects in age-related macular degeneration

    PubMed Central

    Tomi, A; Marin, I

    2014-01-01

    Although AMD (age-related macular degeneration) has been described for over 100 years, there is neither a standard agreement on the definition of specific lesions nor a generally accepted classification system. For example, the age limits for AMD varied widely in different clinical studies; the methods used for examination also vary (visual acuity, perimetry, contrast sensitivity, slit lamp examination of the fundus, retinal photography, fluorescein angiography, indocyanine green angiography). We described the multitude of angiofluorographic aspects in patients with AMD and conceived a classification to be easily used in clinical practice. Although a detailed ophthalmoscopy can often identify the characteristic lesions of AMD, a complete picture is obtained by fluorescein angiography. The angiographic classification of AMD is structured similarly to the clinical one. It has two main patterns, non-exudative and exudative lesions, but it provides more information about the nature of the lesions. In the last three decades, an impressive amount of information regarding the prevalence, progression and risk factors for AMD has been published. The source of this information is mainly represented by the large population studies that are often multicenter studies. Recognizing the clinical signs of AMD and classifying them into different stages is important for the prognosis and the therapeutical decision, but also for conceiving study protocols. PMID:27057244

  10. Ocular surface temperature in age-related macular degeneration.

    PubMed

    Sodi, Andrea; Matteoli, Sara; Giacomelli, Giovanni; Finocchio, Lucia; Corvi, Andrea; Menchini, Ugo

    2014-01-01

    Background. The aim of this study is to investigate the ocular thermographic profiles in age-related macular degeneration (AMD) eyes and age-matched controls to detect possible hemodynamic abnormalities, which could be involved in the pathogenesis of the disease. Methods. 32 eyes with early AMD, 37 eyes with atrophic AMD, 30 eyes affected by untreated neovascular AMD, and 43 eyes with fibrotic AMD were included. The control group consisted of 44 healthy eyes. Exclusion criteria were represented by any other ocular diseases other than AMD, tear film abnormalities, systemic cardiovascular abnormalities, diabetes mellitus, and a body temperature higher than 37.5°C. A total of 186 eyes without pupil dilation were investigated by infrared thermography (FLIR A320). The ocular surface temperature (OST) of three ocular points was calculated by means of an image processing technique from the infrared images. Two-sample t-test and one-way analysis of variance (ANOVA) test were used for statistical analyses. Results. ANOVA analyses showed no significant differences among AMD groups (P value >0.272). OST in AMD patients was significantly lower than in controls (P > 0.05). Conclusions. Considering the possible relationship between ocular blood flow and OST, these findings might support the central role of ischemia in the pathogenesis of AMD. PMID:25436140

  11. Parabiosis for the study of age-related chronic disease

    PubMed Central

    Eggel, Alexander; Wyss-Coray, Tony

    2014-01-01

    Summary Modern medicine wields the power to treat large numbers of diseases and injuries most of us would have died from just a hundred years ago. In view of this tremendous achievement, it can seem as if progress has slowed, and we have been unable to impact the most devastating diseases of our time. Chronic diseases of age such as cardiovascular disease, diabetes, osteoarthritis, or Alzheimer’s disease turn out to be of a complexity that may require transformative ideas and paradigms to understand and treat them. Parabiosis, which mimics aspects of the naturally occurring shared blood supply in conjoined twins in humans and certain animals, may just have the power to be such a transformative experimental paradigm. Forgotten and now shunned in many countries, it has contributed to major breakthroughs in tumor biology, endocrinology, and transplantation research in the past century, and a set of new studies in the US and Britain report stunning advances in stem cell biology and tissue regeneration using parabiosis between young and old mice. We review here briefly the history of parabiosis and discuss its utility to study physiological and pathophysiological processes. We argue that parabiosis is a technique that should enjoy wider acceptance and application, and that policies should be revisited especially if one is to study complex age-related, chronic disorders. PMID:24496774

  12. Eye Conditions in Older Adults: Age-Related Macular Degeneration.

    PubMed

    Iroku-Malize, Tochi; Kirsch, Scott

    2016-06-01

    Age-related macular degeneration (AMD) causes a progressive loss of photoreceptors in the macula. It is the most common cause of legal blindness in the United States, and some form of AMD is thought to affect more than 9 million individuals. Risk factors include older age, smoking, dyslipidemia, obesity, white race, female sex, and a family history of AMD. There are two types of advanced AMD: nonexudative (dry or geographic atrophy) and exudative (wet or neovascular). Both cause progressive central vision loss with intact peripheral vision. Nonexudative AMD accounts for 80% to 90% of all advanced cases, and more than 90% of patients with severe vision loss have exudative AMD. On ophthalmoscopic examination, early findings include drusen (ie, yellow deposits in the retina). Prominent choroidal vessels, subretinal edema, and/or hemorrhage are seen in wet AMD. Regular eye examinations, visual field testing, fluorescein angiography, and optical coherence tomography are used for diagnosis and to guide management. There is no specific therapy for dry AMD, but antioxidant supplementation may be helpful. Intravitreal injection of a vascular endothelial growth factor inhibitor is the treatment of choice for wet AMD. Optical aids and devices can help to maximize function for patients with AMD. PMID:27348529

  13. Differences in cooperative behavior among Damaraland mole rats are consequences of an age-related polyethism.

    PubMed

    Zöttl, Markus; Vullioud, Philippe; Mendonça, Rute; Torrents Ticó, Miquel; Gaynor, David; Mitchell, Adam; Clutton-Brock, Tim

    2016-09-13

    In many cooperative breeders, the contributions of helpers to cooperative activities change with age, resulting in age-related polyethisms. In contrast, some studies of social mole rats (including naked mole rats, Heterocephalus glaber, and Damaraland mole rats, Fukomys damarensis) suggest that individual differences in cooperative behavior are the result of divergent developmental pathways, leading to discrete and permanent functional categories of helpers that resemble the caste systems found in eusocial insects. Here we show that, in Damaraland mole rats, individual contributions to cooperative behavior increase with age and are higher in fast-growing individuals. Individual contributions to different cooperative tasks are intercorrelated and repeatability of cooperative behavior is similar to that found in other cooperatively breeding vertebrates. Our data provide no evidence that nonreproductive individuals show divergent developmental pathways or specialize in particular tasks. Instead of representing a caste system, variation in the behavior of nonreproductive individuals in Damaraland mole rats closely resembles that found in other cooperatively breeding mammals and appears to be a consequence of age-related polyethism. PMID:27588902

  14. Measurement of dynamic variations of polarized light in processed meat due to aging

    NASA Astrophysics Data System (ADS)

    Abubaker, Hamed M.; Tománek, Pavel; Grmela, Lubomír

    2011-05-01

    The propagation of laser light in biological tissues is of growing importance in many medical and food applications. This problem is seriously studied in live science. The biological tissues consist of cells which dimensions are bigger than wavelength of visible light and display large compositional variations, inhomogeneities, and anisotropic structures. Therefore a Mie scattering of transmitted or backscattered light occurs and different polarization states arise. The changes of polarization state due to the multiple scattering of light in the biological cellular tissues also allow measure the freshness of processed victuals. The transmitted and backscattered laser light exhibits multiple scattering on the thin slice of sample. The phenomenon is different if the cellular tissues are living or dead. In the case of meat, there are temporal and dynamic changes not only as a result of chemical process, but also geometric deformations due to the water evaporation from intracellular and extracellular sites. The polarization measurement shows the changes in polarization orientation due to the muscle orientation and meat aging. Two types of measurements were provided: a) Measurement of polarized light reflected and twice transmitted forward and backward through the biological tissue samples - meat slice attached on sample holder mirror. b) Measurement of polarized light transmitted through the biological tissue sample. The relationship between polarization changes and meat freshness, and a dynamic temporal behavior of polarization states in the aged meat is reported.

  15. Radiation Therapy for Neovascular Age-related Macular Degeneration

    SciTech Connect

    Kishan, Amar U.; Modjtahedi, Bobeck S.; Morse, Lawrence S.; Lee, Percy

    2013-03-01

    In the enormity of the public health burden imposed by age-related macular degeneration (ARMD), much effort has been directed toward identifying effective and efficient treatments. Currently, anti-vascular endothelial growth factor (VEGF) injections have demonstrated considerably efficacy in treating neovascular ARMD, but patients require frequent treatment to fully benefit. Here, we review the rationale and evidence for radiation therapy of ARMD. The results of early photon external beam radiation therapy are included to provide a framework for the sequential discussion of evidence for the usage of stereotactic radiation therapy, proton therapy, and brachytherapy. The evidence suggests that these 3 modern modalities can provide a dose-dependent benefit in the treatment of ARMD. Most importantly, preliminary data suggest that all 3 can be used in conjunction with anti-VEGF therapeutics, thereby reducing the frequency of anti-VEGF injections required to maintain visual acuity.

  16. Complement Factor H Polymorphism in Age-Related Macular Degeneration

    PubMed Central

    Klein, Robert J.; Zeiss, Caroline; Chew, Emily Y.; Tsai, Jen-Yue; Sackler, Richard S.; Haynes, Chad; Henning, Alice K.; SanGiovanni, John Paul; Mane, Shrikant M.; Mayne, Susan T.; Bracken, Michael B.; Ferris, Frederick L.; Ott, Jurg; Barnstable, Colin; Hoh., Josephine

    2006-01-01

    Age-related macular degeneration (AMD) is a major cause of blindness in the elderly. We report a genome-wide screen of 96 cases and 50 controls for polymorphisms associated with AMD. Among 116,204 single-nucleotide polymorphisms genotyped, an intronic and common variant in the complement factor H gene (CFH) is strongly associated with AMD (nominal P value <10−7). In individuals homozygous for the risk allele, the likelihood of AMD is increased by a factor of 7.4 (95% confidence interval 2.9 to 19). Resequencing revealed a polymorphism in linkage disequilibrium with the risk allele representing a tyrosine-histidine change at amino acid 402. This polymorphism is in a region of CFH that binds heparin and C-reactive protein. The CFH gene is located on chromosome 1 in a region repeatedly linked to AMD in family-based studies. PMID:15761122

  17. Targeting MAPK Signaling in Age-Related Macular Degeneration

    PubMed Central

    Kyosseva, Svetlana V.

    2016-01-01

    Age-related macular degeneration (AMD) is a major cause of irreversible blindness affecting elderly people in the world. AMD is a complex multifactorial disease associated with demographic, genetics, and environmental risk factors. It is well established that oxidative stress, inflammation, and apoptosis play critical roles in the pathogenesis of AMD. The mitogen-activated protein kinase (MAPK) signaling pathways are activated by diverse extracellular stimuli, including growth factors, mitogens, hormones, cytokines, and different cellular stressors such as oxidative stress. They regulate cell proliferation, differentiation, survival, and apoptosis. This review addresses the novel findings from human and animal studies on the relationship of MAPK signaling with AMD. The use of specific MAPK inhibitors may represent a potential therapeutic target for the treatment of this debilitating eye disease. PMID:27385915

  18. A Revised Hemodynamic Theory of Age-Related Macular Degeneration.

    PubMed

    Gelfand, Bradley D; Ambati, Jayakrishna

    2016-08-01

    Age-related macular degeneration (AMD) afflicts one out of every 40 individuals worldwide, causing irreversible central blindness in millions. The transformation of various tissue layers within the macula in the retina has led to competing conceptual models of the molecular pathways, cell types, and tissues responsible for the onset and progression of AMD. A model that has persisted for over 6 decades is the hemodynamic, or vascular theory of AMD progression, which states that vascular dysfunction of the choroid underlies AMD pathogenesis. Here, we re-evaluate this hypothesis in light of recent advances on molecular, anatomic, and hemodynamic changes underlying choroidal dysfunction in AMD. We propose an updated, detailed model of hemodynamic dysfunction as a mechanism of AMD development and progression. PMID:27423265

  19. Complement factor H polymorphism and age-related macular degeneration.

    PubMed

    Edwards, Albert O; Ritter, Robert; Abel, Kenneth J; Manning, Alisa; Panhuysen, Carolien; Farrer, Lindsay A

    2005-04-15

    Age-related macular degeneration (AMD) is a common, late-onset, and complex trait with multiple risk factors. Concentrating on a region harboring a locus for AMD on 1q25-31, the ARMD1 locus, we tested single-nucleotide polymorphisms for association with AMD in two independent case-control populations. Significant association (P = 4.95 x 10(-10)) was identified within the regulation of complement activation locus and was centered over a tyrosine-402 --> histidine-402 protein polymorphism in the gene encoding complement factor H. Possession of at least one histidine at amino acid position 402 increased the risk of AMD 2.7-fold and may account for 50% of the attributable risk of AMD. PMID:15761121

  20. Gene Therapies for Neovascular Age-Related Macular Degeneration.

    PubMed

    Pechan, Peter; Wadsworth, Samuel; Scaria, Abraham

    2015-07-01

    Pathological neovascularization is a key component of the neovascular form (also known as the wet form) of age-related macular degeneration (AMD) and proliferative diabetic retinopathy. Several preclinical studies have shown that antiangiogenesis strategies are effective for treating neovascular AMD in animal models. Vascular endothelial growth factor (VEGF) is one of the main inducers of ocular neovascularization, and several clinical trials have shown the benefits of neutralizing VEGF in patients with neovascular AMD or diabetic macular edema. In this review, we summarize several preclinical and early-stage clinical trials with intraocular gene therapies, which have the potential to reduce or eliminate the repeated intravitreal injections that are currently required for the treatment of neovascular AMD. PMID:25524721

  1. Habitat-related variation in seedling recruitment of Gentiana pannonica

    NASA Astrophysics Data System (ADS)

    Ekrtová, Ester; Košnar, Jan

    2012-11-01

    Differences in seedling recruitment of Gentiana pannonica were investigated between the primary (relict) and the secondary (semi-natural) forest-free habitats of the Bohemian Forest (870-1200 m a.s.l.) and of the Alps (1045-1935 m a.s.l.) to understand the factors promoting the seedling recruitment of G. pannonica and their importance for species distribution, population structure, and conservation. In the communities with adult plants of G. pannonica, we recorded environmental variables (the slope, the altitude, and the covers of bare ground, litter, and rocks), estimated parameters of the vegetation (the covers of herbs, bryophytes, and dwarf shrubs), and counted the seedlings of G. pannonica. In a field experiment, we investigated seedling survival under different soil moisture regimes. We also observed seasonal dynamics of seedling recruitment in permanent plots over the course of three years. In the primary habitats of both regions, G. pannonica grew in a relatively wide range of communities, and its seedlings occurred in each area. In the secondary habitats of the Bohemian Forest, a very low frequency of the seedlings was recorded. The number of seedlings increased with the covers of the moss layer and of bare soil and decreased with the cover of the herb layer, especially of graminoids. The seedling mortality was significantly lower in the plots with higher soil moistures, and the emergence of new-born seedlings was concentrated in the spring season, when the soil received a high water supply due to melting of snow. For the successful generative reproduction of G. pannonica, our findings highlight the critical importance of the microsites with low levels of competition and of sufficient soil moisture G. pannonica. It seems that because of the long-term lack of grazing disturbances, the structures of the secondary habitats of G. pannonica in the Bohemian Forest have become unfavourable for seedling establishment and generative reproduction of this threatened

  2. Reported Early Family Environment Covaries with Menarcheal Age as a Function of Polymorphic Variation in Estrogen Receptor-α (ESR1)

    PubMed Central

    Manuck, Stephen B.; Craig, Anna E.; Flory, Janine D.; Halder, Indrani; Ferrell, Robert E.

    2010-01-01

    Age at menarche, a sentinel index of pubertal maturation, was examined in relation to early family relationships (conflict, cohesion) and polymorphic variation in the gene encoding estrogen receptor-α (ESR1) in a midlife sample of 455 European American women. Consistent with prior literature, women who reported being raised in families characterized by close interpersonal relationships and little conflict tended to reach menarche at a later age than participants reared in families lacking cohesion and prone to discord. Moreover, this association was moderated by ESR1 variation, such that quality of the family environment covaried positively with menarcheal age among participants homozygous for minor alleles of the two ESR1 polymorphisms studied here (rs9304799, rs2234693), but not among women of other ESR1 genotypes. In addition, a) family relationship variables were unrelated to ESR1 variation, and b) genotype-dependent effects of childhood environment on age at menarche could not be accounted for by personality traits elsewhere shown to explain heritable variation in reported family conflict and cohesion. These findings are consistent with theories of differential susceptibility to environmental influence, as well as the more specific hypothesis (by Belsky) that girls differ genetically in their sensitivity to rearing effects on pubertal maturation. PMID:21262040

  3. Variation of the radiative properties during black carbon aging: theoretical and experimental intercomparison

    DOE PAGESBeta

    He, C.; Liou, K.-N.; Takano, Y.; Zhang, R.; Levy Zamora, M.; Yang, P.; Li, Q.; Leung, L. R.

    2015-10-28

    A theoretical black carbon (BC) aging model is developed to account for three typical evolution stages, namely, freshly emitted aggregates, BC coated by soluble material, and BC particles undergoing further hygroscopic growth. The geometric-optics surface-wave (GOS) approach is employed to compute the BC single-scattering properties at each aging stage, which are subsequently compared with laboratory measurements. Theoretical calculations are consistent with measurements in extinction and absorption cross sections for fresh BC aggregates with different BC sizes (i.e., mobility diameters of 155, 245, and 320 nm), with differences of ≤ 25 %. The measured optical cross sections for BC coated bymore » sulfuric acid and for that undergoing further hygroscopic growth are generally captured (differences < 30 %) by theoretical calculations using a concentric core-shell structure, with an overestimate in extinction and absorption of the smallest BC size and an underestimate in scattering of the largest BC size. We find that the absorption and scattering cross sections of fresh BC aggregates vary by 20–40 and 50–65 %, respectively, due to the use of upper (1.95–0.79i) and lower (1.75–0.63i) bounds of BC refractive index, while the variations are < 20 % in absorption and < 50 % in scattering in the case of coated BC particles. Sensitivity analyses of the BC morphology show that the optical properties of fresh BC aggregates are more sensitive to fractal dimension than primary spherule size. The absorption and scattering cross sections of coated BC particles vary by more than a factor of 2 due to different coating structures. We find an increase of 20–250 % in absorption and a factor of 3–15 in scattering during aging, significantly depending on coating morphology and aging stages. This study suggests that an accurate estimate of BC radiative effects requires the incorporation of a dynamic BC aging process that accounts for realistic coating structures in

  4. Emerging roles of frailty and inflammaging in risk assessment of age-related chronic diseases in older adults: the intersection between aging biology and personalized medicine.

    PubMed

    Wu, I-Chien; Lin, Cheng-Chieh; Hsiung, Chao A

    2015-01-01

    A chronic disease in older adults usually runs a course that is less predictable than in younger individuals. Unexplained variations in disease incidence, prognosis, therapeutic responses, and toxicity are frequently observed among older adults. This heterogeneity poses huge challenges to the current one-size-fits-all health care systems, and calls for more personalized managements of chronic diseases in older adults. Aging is characterized by progressive deterioration of bodily functions with increasing risk of failure over time. The entire process is hierarchically organized, and progresses from intracellular events to changes at systemic and ultimately organism levels at different rates among different individuals. Aging biology exerts great influences on the development and progression of most age-related chronic diseases. Thus, aging biology could contribute to the complexity of illnesses that increase with age, and aging biomarkers possess a great potential to enable personalized health risk assessment and health care. We review evidences supporting the roles of aging biomarkers in risk assessment of prevalent age-related diseases. Frailty phenotype is an objectively measured indicator of advanced-stage aging that is characterized by organism-level dysfunction. In contrast, altered inflammation markers level signifies an earlier stage between cellular abnormalities and systems dysfunction. Results of human observational studies and randomized controlled trials indicate that these measures, albeit simple, greatly facilitate classification of older patients with cancer, chronic kidney disease, cardiovascular diseases and type 2 diabetes mellitus into groups that vary in disease incidence, prognosis and therapeutic response/toxicity. As the detailed mechanisms underlying the complex biologic process of aging are unraveled in the future, a larger array of biomarkers that correlate with biologic aging at different stages will be discovered. Following the

  5. Life-spanning murine gene expression profiles in relation to chronological and pathological aging in multiple organs

    PubMed Central

    Kuiper, Raoul V; van der Hoeven, Tessa V; Wackers, P.F.K.; Robinson, Joke; van der Horst, Gijsbertus TJ; Dollé, Martijn ET; Vijg, Jan; Breit, Timo M; Hoeijmakers, Jan HJ; van Steeg, Harry

    2013-01-01

    Summary Aging and age-related pathology is a result of a still incompletely-understood intricate web of molecular and cellular processes. We present a C57BL/6J female mice in vivo aging study of five organs (liver, kidney, spleen, lung and brain), in which we compare genome-wide gene expression profiles during chronological aging with pathological changes throughout the entire murine lifespan (13, 26, 52, 78, 104 and 130 weeks). Relating gene expression changes to chronological aging revealed many differentially expressed genes (DEGs) and altered gene-sets (AGSs) were found in most organs, indicative of intra-organ generic aging processes. However, only ≤ 1% of these DEGs are found in all organs. For each organ, at least one of 18 tested pathological parameters showed a good age-predictive value, albeit with much inter- and intra-individual (organ) variation. Relating gene expression changes to pathology-related aging revealed correlated genes and gene-sets, which made it possible to characterize the difference between biological and chronological aging. In liver, kidney and brain, a limited number of overlapping pathology-related AGSs were found. Immune responses appeared to be common, yet the changes were specific in most organs. Furthermore, changes were observed in energy homeostasis, reactive oxygen species, cell cycle, cell motility and DNA damage. Comparison of chronological and pathology-related AGSs revealed substantial overlap and interesting differences. For example, the presence of immune processes in liver pathology-related AGSs which were not detected in chronological aging. The many cellular processes that are only found employing aging–related pathology could provide important new insights into the progress of aging. PMID:23795901

  6. Gene Therapy for Age-Related Macular Degeneration.

    PubMed

    Constable, Ian Jeffery; Blumenkranz, Mark Scott; Schwartz, Steven D; Barone, Sam; Lai, Chooi-May; Rakoczy, Elizabeth Piroska

    2016-01-01

    The purpose of this article was to evaluate safety and signals of efficacy of gene therapy with subretinal rAAV.sFlt-1 for wet age-related macular degeneration (wet AMD). A phase 1 dose-escalating single-center controlled unmasked human clinical trial was followed up by extension of the protocol to a phase 2A single-center trial. rAAV.sFlt-1 vector was used to deliver a naturally occurring anti-vascular endothelial growth factor agent, sFlt-1, into the subretinal space. In phase 1, step 1 randomized 3 subjects to low-dose rAAV.sFlt-1 (1 × 10 vector genomes) and 1 subject to the control arm; step 2 randomized an additional 3 subjects to treatment with high-dose rAAV.sFlt-1 (1 × 10 vector genomes) and 1 subject to the control arm. Follow-up studies demonstrated that rAAV.sFlt-1 was well tolerated with a favorable safety profile in these elderly subjects with wet AMD. Subretinal injection was highly reproducible, and no drug-related adverse events were reported. Procedure-related adverse events were mild and self-resolving. Two phakic patients developed cataract and underwent cataract surgery. Four of the 6 patients responded better than the small control group in this study and historical controls in terms of maintaining vision and a relatively dry retina with zero ranibizumab retreatments per annum. Two patients required 1 ranibizumab injection over the 52-week follow-up period. rAAV.sFlt-1 gene therapy may prove to be a potential adjunct or alternative to conventional intravitreal injection for patients with wet AMD by providing extended delivery of a naturally occurring antiangiogenic protein. PMID:27488071

  7. Age-Related Macular Degeneration: Genetics and Biology.

    PubMed

    Kumaramanickavel, Govindasamy

    2016-01-01

    Age-related macular degeneration (AMD), widely prevalent across the globe, is a major stakeholder among adult visual morbidity and blindness, not only in the Western world but also in Asia. Several risk factors have been identified, including critical genetic factors, which were never imagined 2 decades ago. The etiopathogenesis is emerging to demonstrate that immune and complement-related inflammation pathway members chronically exposed to environmental insults could justifiably influence disease morbidity and treatment outcomes. Approximately half a dozen physiological and biochemical cascades are disrupted in the AMD disease genesis, eventually leading to the distortion and disruption of the subretinal space, subretinal pigment epithelium, and Bruch membrane, thus setting off chaos and disorder for signs and symptoms to manifest. Approximately 3 dozen genetic factors have so far been identified, including the recent ones, through powerful genomic technologies and large robust sample sizes. The noteworthy genetic variants (common and rare) are complement factor H, complement factor H-related genes 1 to 5, C3, C9, ARMS2/HTRA1, vascular endothelial growth factor A, vascular endothelial growth factor receptor 2/KDR, and rare variants (show causal link) such as TIMP3, fibrillin, COL4A3, MMP19, and MMP9. Despite the enormous amount of scientific information generated over the years, diagnostic genetic or biomarker tests are still not available for clinicians to understand the natural course of the disease and its management in a patient. However, further research in the field should reduce this gap not only by aiding the clinician but also through the possibilities of clinical intervention with complement pathway-related inhibitors entering preclinical and clinical trials in the near future. PMID:27488064

  8. Age-Related Differences in Lexical Access Relate to Speech Recognition in Noise.

    PubMed

    Carroll, Rebecca; Warzybok, Anna; Kollmeier, Birger; Ruigendijk, Esther

    2016-01-01

    Vocabulary size has been suggested as a useful measure of "verbal abilities" that correlates with speech recognition scores. Knowing more words is linked to better speech recognition. How vocabulary knowledge translates to general speech recognition mechanisms, how these mechanisms relate to offline speech recognition scores, and how they may be modulated by acoustical distortion or age, is less clear. Age-related differences in linguistic measures may predict age-related differences in speech recognition in noise performance. We hypothesized that speech recognition performance can be predicted by the efficiency of lexical access, which refers to the speed with which a given word can be searched and accessed relative to the size of the mental lexicon. We tested speech recognition in a clinical German sentence-in-noise test at two signal-to-noise ratios (SNRs), in 22 younger (18-35 years) and 22 older (60-78 years) listeners with normal hearing. We also assessed receptive vocabulary, lexical access time, verbal working memory, and hearing thresholds as measures of individual differences. Age group, SNR level, vocabulary size, and lexical access time were significant predictors of individual speech recognition scores, but working memory and hearing threshold were not. Interestingly, longer accessing times were correlated with better speech recognition scores. Hierarchical regression models for each subset of age group and SNR showed very similar patterns: the combination of vocabulary size and lexical access time contributed most to speech recognition performance; only for the younger group at the better SNR (yielding about 85% correct speech recognition) did vocabulary size alone predict performance. Our data suggest that successful speech recognition in noise is mainly modulated by the efficiency of lexical access. This suggests that older adults' poorer performance in the speech recognition task may have arisen from reduced efficiency in lexical access; with an

  9. Age-Related Differences in Lexical Access Relate to Speech Recognition in Noise

    PubMed Central

    Carroll, Rebecca; Warzybok, Anna; Kollmeier, Birger; Ruigendijk, Esther

    2016-01-01

    Vocabulary size has been suggested as a useful measure of “verbal abilities” that correlates with speech recognition scores. Knowing more words is linked to better speech recognition. How vocabulary knowledge translates to general speech recognition mechanisms, how these mechanisms relate to offline speech recognition scores, and how they may be modulated by acoustical distortion or age, is less clear. Age-related differences in linguistic measures may predict age-related differences in speech recognition in noise performance. We hypothesized that speech recognition performance can be predicted by the efficiency of lexical access, which refers to the speed with which a given word can be searched and accessed relative to the size of the mental lexicon. We tested speech recognition in a clinical German sentence-in-noise test at two signal-to-noise ratios (SNRs), in 22 younger (18–35 years) and 22 older (60–78 years) listeners with normal hearing. We also assessed receptive vocabulary, lexical access time, verbal working memory, and hearing thresholds as measures of individual differences. Age group, SNR level, vocabulary size, and lexical access time were significant predictors of individual speech recognition scores, but working memory and hearing threshold were not. Interestingly, longer accessing times were correlated with better speech recognition scores. Hierarchical regression models for each subset of age group and SNR showed very similar patterns: the combination of vocabulary size and lexical access time contributed most to speech recognition performance; only for the younger group at the better SNR (yielding about 85% correct speech recognition) did vocabulary size alone predict performance. Our data suggest that successful speech recognition in noise is mainly modulated by the efficiency of lexical access. This suggests that older adults’ poorer performance in the speech recognition task may have arisen from reduced efficiency in lexical access

  10. Federal Interagency Forum on Aging-Related Statistics

    MedlinePlus

    Member Agencies Federal Agency Login X Administration on Aging Agency for Healthcare Research and Quality Bureau of ... National Center for Health Statistics National Institute on Aging Office of the Assistant Secretary for Planning & Evaluation, ...

  11. Factors affecting the relative age effect in NHL athletes

    PubMed Central

    Parent-Harvey, Caroline I.; Desjardins, Christophe; Harvey, Edward J.

    2014-01-01

    Background The relative age effect (RAE) has been reported for a number of different activities. The RAE is the phenomena whereby players born in the first few months of a competition year are advantaged for selection to elite sports. Much of the literature has identified elite male athletics, such as the National Hockey League (NHL), as having consistently large RAEs. We propose that RAE may be lessened in the NHL since the last examination. Methods We examined demographic and selection factors to understand current NHL selection biases. Results We found that RAE was weak and was only evident when birth dates were broken into year halves. Players born in the first half of the year were relatively advantaged for entry into the NHL. We found that the RAE is smaller than reported in previous studies. Intraplayer comparisons for multiple factors, including place of birth, country of play, type of hockey played, height and weight, revealed no differences. Players who were not drafted (e.g., free agents) or who played university hockey in North America had no apparent RAE. Conclusion We found little evidence of an RAE in the current NHL player rosters. A larger study of all Canadian minor hockey intercity teams could help determine the existence of an RAE. PMID:24869606

  12. Oocyte cryopreservation for age-related fertility loss.

    PubMed

    Dondorp, W; de Wert, G; Pennings, G; Shenfield, F; Devroey, P; Tarlatzis, B; Barri, P; Diedrich, K

    2012-05-01

    The recent introduction of oocyte vitrification has significantly advanced the outcome of oocyte cryopreservation, leading to clinical results comparable to those achieved in IVF using fresh oocytes, as reported by experienced centres. This has lead to new debate, both in the professional community and in society at large, about the acceptability of offering this technology to reproductively healthy women who want to cryopreserve their oocytes against the threat of time. Given the many demands calling for simultaneous realization in a relatively short period of their lives, many women who want to have children feel to be under considerable pressure. The option of oocyte cryopreservation may in fact give them more breathing space. In this document, it is concluded that the arguments against allowing this application of the technology are not convincing. The recommendations include the need for adequate information of women interested in oocyte cryopreservation, also in order to avoid raising false hopes. The message must remain that women's best chances of having a healthy child are through natural reproduction at a relative early age. Centres offering this service must have the necessary expertise to employ oocyte cryopreservation efficiently with the so far non-standardized protocols. As data about long-term safety is still lacking, centres also have a responsibility to contribute to the collection of these data. PMID:22357771

  13. Pachychoroid neovasculopathy and age-related macular degeneration

    PubMed Central

    Miyake, Masahiro; Ooto, Sotaro; Yamashiro, Kenji; Takahashi, Ayako; Yoshikawa, Munemitsu; Akagi-Kurashige, Yumiko; Ueda-Arakawa, Naoko; Oishi, Akio; Nakanishi, Hideo; Tamura, Hiroshi; Tsujikawa, Akitaka; Yoshimura, Nagahisa

    2015-01-01

    Pachychoroid neovasculopathy is a recently proposed clinical entity of choroidal neovascularization (CNV). As it often masquerades as neovascular age-related macular degeneration (AMD), it is currently controversial whether pachychoroid neovasculopathy should be distinguished from neovascular AMD. This is because its characteristics have yet to be well described. To estimate the relative prevalence of pachychoroid neovasculopathy in comparison with neovascular AMD and to investigate the phenotypic/genetic differences of the two diseases, we evaluated 200 consecutive Japanese patients who agreed to participate in the genetic study and diagnosed with pachychoroid neovasculopathy or neovascular AMD. Pachychoroid neovasculopathy was observed in 39 individuals (19.5%), which corresponds to one fourth of neovascular AMD. Patients with pachychoroid neovasculopathy were significantly younger (p = 5.1 × 10−5) and showed a greater subfoveal choroidal thickness (p = 3.4 × 10−14). Their genetic susceptibility to AMD was significantly lower than that of neovascular AMD; ARMS2 rs10490924 (p = 0.029), CFH rs800292 (p = 0.013) and genetic risk score calculated from 11 AMD susceptibility genes (p = 3.8 × 10−3). Current results implicate that the etiologies of the two conditions must be different. Thus, it will be necessary to distinguish these two conditions in future studies. PMID:26542071

  14. Modifiable risk factors for age-related macular degeneration.

    PubMed

    Guymer, Robyn H; Chong, Elaine Wei-Tinn

    2006-05-01

    Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in Australia and other Western countries. As there is no cure for AMD, and treatments to stop its progression have met with limited success, there is an interest in identifying modifiable risk factors to prevent or slow disease progression. To date, smoking is the only proven modifiable risk factor for AMD. Other factors under study include (i) cardiovascular risk factors such as hypertension, body mass index, and atherosclerosis; and (ii) dietary risk factors including fat and antioxidant intake, but so far these studies have produced conflicting results. Dietary fat in relation to AMD has recently attracted media attention. Despite very limited work supporting an association between vegetable fat and AMD, widespread publicity advocating margarine as a cause of AMD and encouraging use of butter instead has caused confusion and anxiety among sufferers of AMD and the general public, as well as concern among health professionals. The antioxidant carotenoids--lutein and zeaxanthin--found in dark green or yellow vegetables exist in high concentrations in the macula and are hypothesised to play a protective role. Of nine controlled trials of supplementation with carotenoids and other antioxidants, three suggested that various combinations of antioxidants and carotenoids were protective. While a low-fat diet rich in dark green and yellow vegetables is advocated in general, any specific recommendations regarding certain fats or antioxidant supplementation and AMD are not based on consistent findings at this stage. PMID:16646746

  15. Could seasonal variation in testosterone levels in men be related to sleep?

    PubMed

    Svartberg, J; Barrett-Connor, E

    2004-09-01

    We have previously reported seasonal variations in both total and free testosterone in men living in north Norway. The aim of this cross-sectional study was to determine whether seasonal variation in testosterone also occurs in men living in geographical areas with less extreme seasonal variation in sunlight and temperature. In 915 men aged 24-91 years from Rancho Bernardo, a suburb of San Diego in southern California, we found that neither total nor bioavailable testosterone varied by season, with or without adjustments for age and anthropometric measurements. Of all examined covariates, only physical activity showed a seasonal variation, with a peak in August (p < 0.001), and adjusting for physical activity did not change the lack of seasonal variation in testosterone. In addition, there was no association between testosterone and mean air temperature, or testosterone and possible hours of sunshine. We conclude that men living in southern California show no seasonal variation in testosterone levels. One possible explanation, besides the difference in climate, for the diverging findings between our previous study and the present study is different sleep patterns. PMID:15669539

  16. Age-Related Changes in Acoustic Characteristics of Adult Speech

    ERIC Educational Resources Information Center

    Torre, Peter, III; Barlow, Jessica A.

    2009-01-01

    This paper addresses effects of age and sex on certain acoustic properties of speech, given conflicting findings on such effects reported in prior research. The speech of 27 younger adults (15 women, 12 men; mean age 25.5 years) and 59 older adults (32 women, 27 men; mean age 75.2 years) was evaluated for identification of differences for sex and…

  17. Age-Related Differences in Evaluating Developmental Stability

    ERIC Educational Resources Information Center

    Mustafic, Maida; Freund, Alexandra M.

    2013-01-01

    Two studies examined the hypothesis that the evaluation of developmental stability changes across adulthood. Results of Study 1 ("N" = 119) supported the expectation that older adults ("M"[subscript age] = 65.29 years)--compared to younger ("M"[subscript age] = 23.38 years) and middle-aged adults…

  18. Survey and critique of studies related to shift length variations in nursing from 1970 to 1993.

    PubMed

    Bernreuter, M; Sullivan, M

    1995-04-01

    The purpose of this study was to describe the current status, stage of staffing change, and findings of research relating to shift length variations in nursing. This was accomplished through a review of the literature to (a) evaluate the quality of the research, (b) summarize and draw conclusions related to variations in nursing shift length, and (c) identify gaps in the literature for the purpose of making recommendations for future studies related to nursing shift length variations. Multiple methods were utilized for locating potential studies to include in this project. Smith and Stullenbarger's (1991) Quality of Study instrument was used to rate the studies. None of the research reviewed explicitly identified a conceptual or theoretical framework or model, and few studies could be classified as scientifically rigorous. This study illuminates the state of the art and findings related to length of shift variations in nursing, and as such has implications for practice and research in nursing service administration. PMID:7790158

  19. Variation of benefits and harms of breast cancer screening with age.

    PubMed

    Harris, R

    1997-01-01

    The critical issue in deciding whether to recommend breast cancer screening for women in their forties is to determine whether potential benefits are substantially greater than potential harms. Recent evidence from randomized clinical trials makes it likely that, after 10-12 years of follow-up, there is a real benefit from screening women ages 40-49, on the order of a 15-20% reduction in the relative risk of breast cancer death. This relative risk reduction translates into an absolute risk reduction of 1-2 women whose lives are extended from screening 1,000 women in their forties annually for 10 years (i.e., about one life extended per 5,000 mammograms). The absolute benefit of screening increases with age. Evidence about potential harms is less well established, but it is compelling that there are 15-40 times as many false positive as true positive mammograms (depending on the patient's age), and that at least some of the women with false positive mammograms have ongoing psychological distress as a result. Some 30% of all women who are screened annually during their forties will have at least one false positive mammogram and this probability likely decreases with advancing age. If the balance between benefits and harms is judged to be a "close call" for women in their forties, a blanket recommendation for all is inappropriate. Instead, each woman in her forties should be helped to understand the pros and cons of screening, to clarify her own values, and to consider with her primary care physician what decision would be best for her. PMID:9709290

  20. Increasing Sibling Relative Risk of Survival to Older and Older Ages and the Importance of Precise Definitions of "Aging," "Life Span," and "Longevity".

    PubMed

    Sebastiani, Paola; Nussbaum, Lisa; Andersen, Stacy L; Black, Mara J; Perls, Thomas T

    2016-03-01

    The lack of a formal definition of human longevity continues to generate confusion about its genetic and nongenetic determinants. In order to characterize how differences in birth year cohorts and percentiles of survival are associated with familial contribution to variation in survival, we estimated sibling relative risk of living to increasingly rare percentiles of survival based on a dataset of 1,917 validated sibships each containing at least one individual living to age 90 years. About 1,042 of the sibships included at least one individual who survived to age 100 and 511 included at least one individual who survived to age 105 and older. We show that sibling relative risk increases with older ages, sex, and earlier birth year cohorts of the proband and siblings of male 90-year-olds (5th percentile of survival) have 1.73 (95% CI: 1.5; 2.0) times the chance of living to age 90, while siblings of both male and female probands who survived to age 105 years (~0.01 percentile of survival) have 35.6 (95%CI: 15.1; 67.7) times the chance of living to age 105 compared with population controls. These results emphasize the importance of consistently defining the longevity phenotype in terms of rarity of survival for appropriate comparisons across studies. PMID:25814633

  1. Aging and associative recognition: A view from the DRYAD model of age-related memory deficits.

    PubMed

    Benjamin, Aaron S

    2016-02-01

    How do we best characterize the memory deficits that accompany aging? A popular hypothesis, articulated originally by Naveh-Benjamin (2000) and reviewed in the accompanying article by Smyth and Naveh-Benjamin (2016), suggests that older adults are selectively deficient in establishing associations between to-be-learned memoranda and as a result have deficits in memory for sources or contexts. An alternative proposal, called density of representations yields age-related deficits (DRYAD) and outlined in recent articles by Benjamin (2010) and colleagues (Benjamin, Diaz, Matzen, & Johnson, 2012), attributes disproportionate deficits in memory to a global, rather than a selective, deficit of memory. In an attempt to adjudicate between these competing positions, Smyth and Naveh-Benjamin (2016) discussed 2 sets of experimental data that they claim speak against the global deficit model. Here I review some general principles of how the global-deficit view is applied to experimental paradigms and demonstrate that even a simplified form of DRYAD can comfortably accommodate the critical findings cited by Smyth and Naveh-Benjamin. I also evaluate aspects of their results that may be problematic for DRYAD and describe ways in which DRYAD's account of associative recognition can be falsified. I end with a discussion of the complementary strengths and weaknesses of the 2 approaches and consider ways in which the associative deficit hypothesis and DRYAD might work more profitably together than apart. PMID:26866587

  2. [Epigenetic mutagenesis as program of age-related protein dysfunction and aging].

    PubMed

    Romanov, G A; Sukhoverov, V S; Vanyushin, B F

    2015-01-01

    DNA methylation plays an important polyfunctional role in ontogenesis of human and mammals. A steep rise in probability of mutational substitution of CpG dinucleotide on TpG dinucleotide in the genome is one of the consequences of DNA methylation. All spectrum (17) of possible DNA and protein mutations caused by CpG-dinucleotide methylation in DNA were characterized, and the three most dangerous mutations (able to result in protein inactivation) were isolated. The computer program that allows one to predict all most probable mutations in the analyzed gene and encoded protein was created. On the example of genes from humans and various mammals, it was demonstrated that the amount of potentially dangerous sites of epigenetic mutagenesis in exons was drastically decreased as a result of genome evolution. But, at the same time, unforced preservation of such sites and their persistence were established, indicating the occurrence of age-related protein dysfunction built into the genome epigenetic program, resulting in apoptosis and aging; this program is based on the set and position of methylated codons in exonic gene regions. It is assumed that the program of epigenetic mutagenesis limits the lifetime of an individual, accelerating the deliverance of the population from long-lived individuals that completed the reproductive period. PMID:26021123

  3. Primary age-related tauopathy (PART): a common pathology associated with human aging.

    PubMed

    Crary, John F; Trojanowski, John Q; Schneider, Julie A; Abisambra, Jose F; Abner, Erin L; Alafuzoff, Irina; Arnold, Steven E; Attems, Johannes; Beach, Thomas G; Bigio, Eileen H; Cairns, Nigel J; Dickson, Dennis W; Gearing, Marla; Grinberg, Lea T; Hof, Patrick R; Hyman, Bradley T; Jellinger, Kurt; Jicha, Gregory A; Kovacs, Gabor G; Knopman, David S; Kofler, Julia; Kukull, Walter A; Mackenzie, Ian R; Masliah, Eliezer; McKee, Ann; Montine, Thomas J; Murray, Melissa E; Neltner, Janna H; Santa-Maria, Ismael; Seeley, William W; Serrano-Pozo, Alberto; Shelanski, Michael L; Stein, Thor; Takao, Masaki; Thal, Dietmar R; Toledo, Jonathan B; Troncoso, Juan C; Vonsattel, Jean Paul; White, Charles L; Wisniewski, Thomas; Woltjer, Randall L; Yamada, Masahito; Nelson, Peter T

    2014-12-01

    We recommend a new term, "primary age-related tauopathy" (PART), to describe a pathology that is commonly observed in the brains of aged individuals. Many autopsy studies have reported brains with neurofibrillary tangles (NFTs) that are indistinguishable from those of Alzheimer's disease (AD), in the absence of amyloid (Aβ) plaques. For these "NFT+/Aβ-" brains, for which formal criteria for AD neuropathologic changes are not met, the NFTs are mostly restricted to structures in the medial temporal lobe, basal forebrain, brainstem, and olfactory areas (bulb and cortex). Symptoms in persons with PART usually range from normal to amnestic cognitive changes, with only a minority exhibiting profound impairment. Because cognitive impairment is often mild, existing clinicopathologic designations, such as "tangle-only dementia" and "tangle-predominant senile dementia", are imprecise and not appropriate for most subjects. PART is almost universally detectable at autopsy among elderly individuals, yet this pathological process cannot be specifically identified pre-mortem at the present time. Improved biomarkers and tau imaging may enable diagnosis of PART in clinical settings in the future. Indeed, recent studies have identified a common biomarker profile consisting of temporal lobe atrophy and tauopathy without evidence of Aβ accumulation. For both researchers and clinicians, a revised nomenclature will raise awareness of this extremely common pathologic change while providing a conceptual foundation for future studies. Prior reports that have elucidated features of the pathologic entity we refer to as PART are discussed, and working neuropathological diagnostic criteria are proposed. PMID:25348064

  4. Oxidative stress, innate immunity, and age-related macular degeneration

    PubMed Central

    Shaw, Peter X.; Stiles, Travis; Douglas, Christopher; Ho, Daisy; Fan, Wei; Du, Hongjun; Xiao, Xu

    2016-01-01

    Age-related macular degeneration (AMD) is a leading cause of vision loss affecting tens of millions of elderly worldwide. Early AMD is characterized by the appearance of soft drusen, as well as pigmentary changes in the retinal pigment epithelium (RPE). These soft, confluent drusen can progress into two forms of advanced AMD: geographic atrophy (GA, or dry AMD) or choroidal neovascularization (CNV, or wet AMD). Both forms of AMD result in a similar clinical progression in terms of loss of central vision. The exact mechanism for developing early AMD, as well as triggers responsible for progressing to advanced stage of disease, is still largely unknown. However, significant evidence exists demonstrating a complex interplay of genetic and environmental factors as causes of AMD progression. Multiple genes and/or single nucleotide polymorphisms (SNPs) have been found associated with AMD, including various genes involved in the complement pathway, lipid metabolism and extracellular matrix (ECM) remodeling. Of the known genetic contributors to disease risk, the CFH Y402H and HTRA1/ARMS polymorphisms contribute to more than 50% of the genetic risk for AMD. Environmentally, oxidative stress plays a critical role in many aging diseases including cardiovascular disease, cancer, Alzheimer’s disease and AMD. Due to the exposure to sunlight and high oxygen concentration, the oxidative stress burden is higher in the eye than other tissues, which can be further complicated by additional oxidative stressors such as smoking. Increasingly, evidence is accumulating suggesting that functional abnormalities of the innate immune system incurred via high risk genotypes may be contributing to the pathogenesis of AMD by altering the inflammatory homeostasis in the eye, specifically in the handling of oxidation products. As the eye in non-pathological instances maintains a low level of inflammation despite the presence of a relative abundance of potentially inflammatory molecules, we have

  5. A validated age-related normative model for male total testosterone shows increasing variance but no decline after age 40 years.

    PubMed

    Kelsey, Thomas W; Li, Lucy Q; Mitchell, Rod T; Whelan, Ashley; Anderson, Richard A; Wallace, W Hamish B

    2014-01-01

    The diagnosis of hypogonadism in human males includes identification of low serum testosterone levels, and hence there is an underlying assumption that normal ranges of testosterone for the healthy population are known for all ages. However, to our knowledge, no such reference model exists in the literature, and hence the availability of an applicable biochemical reference range would be helpful for the clinical assessment of hypogonadal men. In this study, using model selection and validation analysis of data identified and extracted from thirteen studies, we derive and validate a normative model of total testosterone across the lifespan in healthy men. We show that total testosterone peaks [mean (2.5-97.5 percentile)] at 15.4 (7.2-31.1) nmol/L at an average age of 19 years, and falls in the average case [mean (2.5-97.5 percentile)] to 13.0 (6.6-25.3) nmol/L by age 40 years, but we find no evidence for a further fall in mean total testosterone with increasing age through to old age. However we do show that there is an increased variation in total testosterone levels with advancing age after age 40 years. This model provides the age related reference ranges needed to support research and clinical decision making in males who have symptoms that may be due to hypogonadism. PMID:25295520

  6. Integrative and semantic relations equally alleviate age-related associative memory deficits.

    PubMed

    Badham, Stephen P; Estes, Zachary; Maylor, Elizabeth A

    2012-03-01

    Two experiments compared effects of integrative and semantic relations between pairs of words on lexical and memory processes in old age. Integrative relations occur when two dissimilar and unassociated words are linked together to form a coherent phrase (e.g., horse-doctor). In Experiment 1, older adults completed a lexical-decision task where prime and target words were related either integratively or semantically. The two types of relation both facilitated responses compared to a baseline condition, demonstrating that priming can occur in older adults with minimal preexisting associations between primes and targets. In Experiment 2, young and older adults completed a cued recall task with integrative, semantic, and unrelated word pairs. Both integrative and semantic pairs showed significantly smaller age differences in associative memory compared to unrelated pairs. Integrative relations facilitated older adults' memory to a similar extent as semantic relations despite having few preexisting associations in memory. Integratability of stimuli is therefore a new factor that reduces associative deficits in older adults, most likely by supporting encoding and retrieval mechanisms. PMID:21639644

  7. Analytical approaches to the diagnosis and treatment of aging and aging-related disease: redox status and proteomics.

    PubMed

    Calabrese, V; Dattilo, S; Petralia, A; Parenti, R; Pennisi, M; Koverech, G; Calabrese, V; Graziano, A; Monte, I; Maiolino, L; Ferreri, T; Calabrese, E J

    2015-05-01

    Basal levels of oxidants are indispensible for redox signaling to produce adaptive cellular responses such as vitagenes linked to cell survival; however, at higher levels, they are detrimental to cells, contributing to aging and to the pathogenesis of numerous age-related diseases. Aging is a complex systemic process and the major gap in aging research reminds the insufficient knowledge about pathways shifting from normal "healthy" aging to disease-associated pathological aging. The major complication of normal "healthy" aging is in fact the increasing risk of age-related diseases such as cardiovascular diseases, diabetes mellitus, and neurodegenerative pathologies that can adversely affect the quality of life in general, with enhanced incidences of comorbidities and mortality. In this context, global "omics" approaches may help to dissect and fully study the cellular and molecular mechanisms of aging and age-associated processes. The proteome, being more close to the phenotype than the transcriptome and more stable than the metabolome, represents the most promising "omics" field in aging research. In the present study, we exploit recent advances in the redox biology of aging and discuss the potential of proteomics approaches as innovative tools for monitoring at the proteome level the extent of protein oxidative insult and related modifications with the identification of targeted proteins. PMID:25824967

  8. Carnosine and Related Peptides: Therapeutic Potential in Age-Related Disorders.

    PubMed

    Cararo, José H; Streck, Emilio L; Schuck, Patricia F; Ferreira, Gustavo da C

    2015-09-01

    Imidazole dipeptides (ID), such as carnosine (β-alanyl-L-histidine), are compounds widely distributed in excitable tissues of vertebrates. ID are also endowed of several biochemical properties in biological tissues, including antioxidant, bivalent metal ion chelating, proton buffering, and carbonyl scavenger activities. Furthermore, remarkable biological effects have been assigned to such compounds in age-related human disorders and in patients whose activity of serum carnosinase is deficient or undetectable. Nevertheless, the precise biological role of ID is still to be unraveled. In the present review we shall discuss some evidences from clinical and basic studies for the utilization of ID as a drug therapy for age-related human disorders. PMID:26425391

  9. Carnosine and Related Peptides: Therapeutic Potential in Age-Related Disorders

    PubMed Central

    Cararo, José H; Streck, Emilio L; Schuck, Patricia F; Ferreira, Gustavo da C

    2015-01-01

    Imidazole dipeptides (ID), such as carnosine (β-alanyl-L-histidine), are compounds widely distributed in excitable tissues of vertebrates. ID are also endowed of several biochemical properties in biological tissues, including antioxidant, bivalent metal ion chelating, proton buffering, and carbonyl scavenger activities. Furthermore, remarkable biological effects have been assigned to such compounds in age-related human disorders and in patients whose activity of serum carnosinase is deficient or undetectable. Nevertheless, the precise biological role of ID is still to be unraveled. In the present review we shall discuss some evidences from clinical and basic studies for the utilization of ID as a drug therapy for age-related human disorders. PMID:26425391

  10. Variation in honey bee gut microbial diversity affected by ontogenetic stage, age and geographic location.

    PubMed

    Hroncova, Zuzana; Havlik, Jaroslav; Killer, Jiri; Doskocil, Ivo; Tyl, Jan; Kamler, Martin; Titera, Dalibor; Hakl, Josef; Mrazek, Jakub; Bunesova, Vera; Rada, Vojtech

    2015-01-01

    Social honey bees, Apis mellifera, host a set of distinct microbiota, which is similar across the continents and various honey bee species. Some of these bacteria, such as lactobacilli, have been linked to immunity and defence against pathogens. Pathogen defence is crucial, particularly in larval stages, as many pathogens affect the brood. However, information on larval microbiota is conflicting. Seven developmental stages and drones were sampled from 3 colonies at each of the 4 geographic locations of A. mellifera carnica, and the samples were maintained separately for analysis. We analysed the variation and abundance of important bacterial groups and taxa in the collected bees. Major bacterial groups were evaluated over the entire life of honey bee individuals, where digestive tracts of same aged bees were sampled in the course of time. The results showed that the microbial tract of 6-day-old 5th instar larvae were nearly equally rich in total microbial counts per total digestive tract weight as foraging bees, showing a high percentage of various lactobacilli (Firmicutes) and Gilliamella apicola (Gammaproteobacteria 1). However, during pupation, microbial counts were significantly reduced but recovered quickly by 6 days post-emergence. Between emergence and day 6, imago reached the highest counts of Firmicutes and Gammaproteobacteria, which then gradually declined with bee age. Redundancy analysis conducted using denaturing gradient gel electrophoresis identified bacterial species that were characteristic of each developmental stage. The results suggest that 3-day 4th instar larvae contain low microbial counts that increase 2-fold by day 6 and then decrease during pupation. Microbial succession of the imago begins soon after emergence. We found that bacterial counts do not show only yearly cycles within a colony, but vary on the individual level. Sampling and pooling adult bees or 6th day larvae may lead to high errors and variability, as both of these stages may

  11. Variation in Honey Bee Gut Microbial Diversity Affected by Ontogenetic Stage, Age and Geographic Location

    PubMed Central

    Hroncova, Zuzana; Havlik, Jaroslav; Killer, Jiri; Doskocil, Ivo; Tyl, Jan; Kamler,