scholarly journals Age‐related changes in chimpanzee ( Pan troglodytes ) cognition: Cross‐sectional and longitudinal analyses

2020 ◽  
Author(s):  
William D. Hopkins ◽  
Mary C. Mareno ◽  
Sarah J. Neal Webb ◽  
Steven J. Schapiro ◽  
Mary A. Raghanti ◽  
...  
Keyword(s):  
Pan Troglodytes ◽  
Longitudinal Analyses ◽  
Cross Sectional ◽  
Age Related ◽  
Age Related Changes

scholarly journals Age-Related Changes in Chimpanzee (Pan troglodytes) Cognition: Cross-Sectional and Longitudinal Analyses

2020 ◽  
Author(s):  
William D Hopkins ◽  
Mary Catherine Mareno ◽  
Sarah J Neal Webb ◽  
Steve J Schapiro ◽  
Mary Ann Raghanti ◽  
...  
Keyword(s):  
Nonhuman Primates ◽  
Cognitive Test ◽  
Comparative Biology ◽  
Longitudinal Analyses ◽  
Middle Aged ◽  
Cross Sectional ◽  
Collective Data ◽  
Age Related ◽  
Biology Of Aging ◽  
Age Related Changes

AbstractChimpanzees are the species most closely related to humans yet age-related changes in brain and cognition remain poorly understood. The lack of studies on age-related changes in cognition in chimpanzees is particularly unfortunate in light of the recent evidence demonstrating that this species naturally develops Alzheimer’s disease (AD) neuropathology. Here, we tested 213 young, middle-aged, and elderly chimpanzees on the Primate Cognitive Test Battery (PCTB), a set of 13 tasks that assess physical and social cognition in nonhuman primates. A subset of these chimpanzees (n=146) were tested a second time on a portion of the PCTB tasks as a means of evaluating longitudinal changes in cognition. Cross-sectional analyses revealed a significant quadratic association between age and cognition with younger and older chimpanzees performing more poorly than middle-aged individuals. Longitudinal analyses showed that, while young chimpanzees’ performance improved from test 1 to test 2, middle-aged and elderly chimpanzees’ performance showed significant decline over time. The collective data show that chimpanzees, like other nonhuman primates, show age-related decline in cognition. Further investigations into whether the observed cognitive decline is associated with AD pathologies in chimpanzees would be invaluable in understanding the comparative biology of aging and neuropathology in primates.

scholarly journals Age-Related Changes in Serum Testosterone and Sex Hormone Binding Globulin in Australian Men: Longitudinal Analyses of Two Geographically Separate Regional Cohorts

2007 ◽  
Vol 92 (9) ◽  
pp. 3599-3603 ◽  
Author(s):  
Peter Y. Liu ◽  
Jonathan Beilin ◽  
Christian Meier ◽  
Tuan V. Nguyen ◽  
Jacqueline R. Center ◽  
...  
Keyword(s):  
Serum Testosterone ◽  
Community Dwelling ◽  
Sex Hormone Binding Globulin ◽  
Total Testosterone ◽  
Longitudinal Analyses ◽  
Cross Sectional ◽  
Age Related ◽  
Eastern Australia ◽  
Different Populations ◽  
Age Related Changes

Abstract Background: Cross-sectional studies from different populations show a variable decline in blood testosterone concentrations as men age. Few population representative cohorts have been followed up over time. Objective: The objective of the study was to quantify longitudinally the change in serum testosterone and SHBG concentrations with age in two well-defined, representative but geographically widely separated regional Australian cohorts. Subjects and Setting: The Busselton cohort comprises individuals aged 18–90 yr residing in Western Australia assessed prospectively since 1981. Sera were assayed from 910 men, from whom further samples were available 14 yr later in 480. The Dubbo cohort involves individuals aged 61–90 yr living in Eastern Australia. Baseline sera were collected from 610 men and additional sera on a second (n = 370) and third (n = 200) occasion from 1989 to 2004. Men from both cohorts are community dwelling and of predominately European origin. Results: Longitudinal analyses show the following: 1) total testosterone declines comparably (P > 0.9) by 1.3% (Busselton) and 0.9% (Dubbo) per annum with the same rates of decline when analyses were restricted to men older than 60 yr of age; 2) annual changes in SHBG were also very similar in age-restricted analyses (2.3% vs. 2.5%, P = 0.48); and 3) the annual increase in SHBG was steeper in middle-aged and older men (P < 10−3vs. young men). These longitudinal changes were all up to 4-fold greater in magnitude, compared with cross-sectional analyses of baseline data. Conclusion: In two separate regional Australian populations, blood testosterone fell and SHBG increased comparably with age. Age-related changes in blood testosterone and SHBG previously described in urban-dwelling men are the same in men who reside in smaller regional cities of another continent.

Ageing Changes in the Tensile Properties of Tendons: Influence of Collagen Fibril Volume Fraction

2008 ◽  
Vol 130 (2) ◽  
Author(s):  
K. L. Goh ◽  
D. F. Holmes ◽  
H.-Y. Lu ◽  
S. Richardson ◽  
K. E. Kadler ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Collagen Fibril ◽  
Volume Fraction ◽  
Area Fraction ◽  
Sectional Area ◽  
Cross Sectional ◽  
P Values ◽  
Age Related ◽  
Fibril Diameter ◽  
Age Related Changes

Connective tissues are biological composites comprising of collagen fibrils embedded in (and reinforcing) the hydrated proteoglycan-rich (PG) gel within the extracellular matrices (ECMs). Age-related changes to the mechanical properties of tissues are often associated with changes to the structure of the ECM, namely, fibril diameter. However, quantitative attempts to correlate fibril diameter to mechanical properties have yielded inconclusive evidence. Here, we described a novel approach that was based on the rule of mixtures for fiber composites to evaluate the dependence of age-related changes in tendon tensile strength (σ) and stiffness (E) on the collagen fibril cross-sectional area fraction (ρ), which is related to the fibril volume fraction. Tail tendons from C57BL6 mice from age groups 1.6–35.3months old were stretched to failure to determine σ and E. Parallel measurements of ρ as a function of age were made using transmission electron microscopy. Mathematical models (rule of mixtures) of fibrils reinforcing a PG gel in tendons were used to investigate the influence of ρ on ageing changes in σ and E. The magnitudes of σ, E, and ρ increased rapidly from 1.6monthsto4.0months (P-values <0.05) before reaching a constant (age independent) from 4.0monthsto29.0months (P-values >0.05); this trend continued for E and ρ (P-values >0.05) from 29.0monthsto35.3months, but not for σ, which decreased gradually (P-values <0.05). Linear regression analysis revealed that age-related changes in σ and E correlated positively to ρ (P-values <0.05). Collagen fibril cross-sectional area fraction ρ is a significant predictor of ageing changes in σ and E in the tail tendons of C57BL6 mice.

The Effect of Education on Age-Related Changes in Three Cognitive Domains: A Cross-Sectional Study in Primary Care

2012 ◽  
Vol 19 (4) ◽  
pp. 287-298 ◽  
Author(s):  
Isabel Pavão Martins ◽  
Carolina Maruta ◽  
Cláudia Silva ◽  
Pedro Rodrigues ◽  
Catarina Chester ◽  
...  
Keyword(s):  
Primary Care ◽  
Cross Sectional Study ◽  
Sectional Study ◽  
Cross Sectional ◽  
Cognitive Domains ◽  
Age Related ◽  
Age Related Changes

scholarly journals Age-related changes in the corpus callosum in early-onset bipolar disorder assessed using volumetric and cross-sectional measurements

2010 ◽  
Vol 4 (3-4) ◽  
pp. 220-231 ◽  
Author(s):  
Melissa Lopez-Larson ◽  
Janis L. Breeze ◽  
David N. Kennedy ◽  
Steven M. Hodge ◽  
Lena Tang ◽  
...  
Keyword(s):  
Bipolar Disorder ◽  
Corpus Callosum ◽  
Early Onset ◽  
Cross Sectional ◽  
Age Related ◽  
Age Related Changes

Age-related changes of song traits in female European Starlings (Sturnus vulgaris)

2010 ◽  
Vol 60 (1) ◽  
pp. 43-59 ◽  
Author(s):  
Denitza Pavlova ◽  
Rianne Pinxten ◽  
Marcel Eens
Keyword(s):  
Vocal Learning ◽  
High Plasticity ◽  
Longitudinal Analyses ◽  
European Starlings ◽  
Cross Sectional ◽  
Song Sharing ◽  
Song Complexity ◽  
Female Song ◽  
Age Related ◽  
The Individual

AbstractIn contrast to male bird song, female song complexity, learning and expression have received much less attention. Female European starlings can produce song of a comparable complexity as males and are also capable of adult vocal learning. Here we recorded song during 3 successive years and investigated variation in song traits (song complexity, song duration and song versatility) in relation to age in captive adult female starlings. We looked at whether individual song traits differ among different age classes (cross-sectional analyses) and whether they change over successive years (longitudinal analyses). Further we studied the repertoire turnover throughout the years, female song sharing in the first year of recording and whether different song traits consistently vary among females across the years. Overall, both cross-sectional and longitudinal analyses showed that repertoire size significantly declined with female age, suggesting that some constraints exist in adult females to maintain large repertoires. Song duration and song versatility appeared to be unrelated to age. Female starlings intensely modified their repertoire across the years by adding new/deleting old phrase types, suggesting a high plasticity as reported in males. Females showed a high variation (between 14% and 83%) in sharing their repertoire, with older females having higher song sharing rates. The individual differences in song complexity and performance were repeatable across the years, which may suggest that song in female starlings is a potential quality indicator trait.

Sex differences in the perceived intensity of breathlessness during exercise with advancing age

2008 ◽  
Vol 104 (6) ◽  
pp. 1583-1593 ◽  
Author(s):  
Dror Ofir ◽  
Pierantonio Laveneziana ◽  
Katherine A. Webb ◽  
Yuk-Miu Lam ◽  
Denis E. O'Donnell
Keyword(s):  
Sex Differences ◽  
Older Women ◽  
Cross Sectional Study ◽  
Inspiratory Muscle ◽  
Cross Sectional ◽  
Respiratory Impairment ◽  
Mechanical Constraints ◽  
Age Related ◽  
Underlying Mechanisms ◽  
Age Related Changes

The prevalence of activity-related breathlessness increases with age, particularly in women, but the specific underlying mechanisms have not been studied. This novel cross-sectional study was undertaken to examine the effects of age and sex, and their interaction, on the perceptual and ventilatory responses to incremental treadmill exercise in 73 healthy participants (age range 40–80 yr old) with normal pulmonary function. Age-related changes at a standardized oxygen uptake (V̇o2) during exercise included significant increases in breathlessness ratings (Borg scale), ventilation (V̇e), ventilatory equivalent for carbon dioxide, and the ratio of tidal volume (Vt) to dynamic inspiratory capacity (IC) (all P < 0.05). These changes were quantitatively similar in women ( n = 39) and in men ( n = 34). For the group as a whole, exertional breathlessness ratings increased as resting static inspiratory muscle strength diminished ( P = 0.05), as exercise ventilation increased relative to capacity ( P = 0.013) and as the Vt/IC ratio increased ( P = 0.003) during exercise. Older women (60–80 yr old, n = 23) reported greater ( P < 0.05) intensity of exertional breathlessness at a standardized V̇o2 and V̇e than age-matched men ( n = 16), despite similar age-related changes in ventilatory demand and dynamic ventilatory mechanics. These increases in breathlessness ratings in older women disappeared when sex differences in baseline maximal ventilatory capacity were accounted for. In conclusion, although increased exertional breathlessness with advancing age is multifactorial, contributory factors included higher ventilatory requirements during exercise, progressive inspiratory muscle weakness, and restrictive mechanical constraints on Vt expansion related to reduced IC. The sensory consequences of this age-related respiratory impairment were more pronounced in women, who, by nature, have relatively reduced maximal ventilatory reserve.

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