Transversely Isotropic Model of Osteonal Cortical Bone: Contribution of Haversian and Resorptive Porosity

1999 ◽  
Author(s):  
X. Neil Dong ◽  
Y. Young Huang ◽  
X. Edward Guo
Keyword(s):  
Cortical Bone ◽  
Transversely Isotropic ◽  
The Elderly ◽  
Haversian Canal ◽  
Isotropic Model ◽  
Elderly Men ◽  
Men And Women ◽  
Age Related ◽  
Osteoclastic Resorption ◽  
Old Men

Abstract Age related changes in porosity of cortical bone have been previously reported. The cortical porosity increases with age in both men and women, from 4.6% in men and 4% in women at age 40 to 10% and more at age 80 (Laval-Jeantet et al., 1983). The porosity is defined as the percentage of cortical bone occupied by vascular and resorption cavities. There are a few quantitative data regarding the influences of Haversian canal and resorption space on porosity. Age related increases in Haversian canal size and Haversian canal number contribute to the increasing porosity of cortical bone for the elderly men and women (Thompson, 1980; Nyssen-behets et al., 1997). The number of osteoclastic resorption space is also greater in the old men than in the young men (Nyssen-Behets et al., 1997).

Aging alters calcium regulation of serum concentration of parathyroid hormone in healthy men

1997 ◽  
Vol 272 (1) ◽  
pp. E139-E146 ◽  
Author(s):  
A. A. Portale ◽  
E. T. Lonergan ◽  
D. M. Tanney ◽  
B. P. Halloran
Keyword(s):  
Parathyroid Hormone ◽  
Young Men ◽  
The Elderly ◽  
Ionized Calcium ◽  
Elderly Men ◽  
Elderly Age ◽  
Healthy Men ◽  
Age Related ◽  
Serum Pth ◽  
The Relationship

We examined the effect of aging on the relationship between the concentrations of blood ionized calcium and of serum parathyroid hormone (PTH) in 22 healthy men [9 elderly (age 74 +/- 2 yr) and 13 young (age 39 +/- 1 yr)] in whom the glomerular filtration rate was > 70 ml/min. Throughout a 24-h period, serum concentrations of PTH in the elderly men were twice those in the young men, whereas blood ionized calcium did not differ between the two groups. With intravenous infusion of calcium gluconate, the minimum PTH concentration was two- to threefold higher in the elderly men. With infusion of NaEDTA. the maximum PTH concentration was 20% higher in the elderly men. The calcium set point for PTH release was higher in the elderly than in the young men (4.71 +/- 0.04 vs. 4.54 +/- 0.03 mg/dl, respectively, P < 0.005). In these healthy men, the age-related increase in serum PTH could not be attributed to a sustained decrease in concentration of either blood ionized calcium or 1,25-hydroxyvitamin D. These findings suggest that, with aging, the relationship between calcium and PTH is altered such that at any given level of calcium, the concentration of PTH is higher.

Changes in the Human Vocal Tract Due to Aging and the Acoustic Correlates of Speech Production

2003 ◽  
Vol 46 (3) ◽  
pp. 689-701 ◽  
Author(s):  
Steve An Xue ◽  
Grace Jianping Hao
Keyword(s):  
Speech Production ◽  
Vocal Tract ◽  
Cost Effective ◽  
The Elderly ◽  
Cross Sectional ◽  
Men And Women ◽  
Acoustic Reflection ◽  
Dimensional Changes ◽  
Formant Frequencies ◽  
Age Related

This investigation used a derivation of acoustic reflection (AR) technology to make cross-sectional measurements of changes due to aging in the oral and pharyngeal lumina of male and female speakers. The purpose of the study was to establish preliminary normative data for such changes and to obtain acoustic measurements of changes due to aging in the formant frequencies of selected spoken vowels and their long-term average spectra (LTAS) analysis. Thirty- eight young men and women and 38 elderly men and women were involved in the study. The oral and pharyngeal lumina of the participants were measured with AR technology, and their formant frequencies were analyzed using the Kay Elemetrics Computerized Speech Lab. The findings have delineated specific and similar patterns of aging changes in human vocal tract configurations in speakers of both genders. Namely, the oral cavity length and volume of elderly speakers increased significantly compared to their young cohorts. The total vocal tract volume of elderly speakers also showed a significant increment, whereas the total vocal tract length of elderly speakers did not differ significantly from their young cohorts. Elderly speakers of both genders also showed similar patterns of acoustic changes of speech production, that is, consistent lowering of formant frequencies (especially F1) across selected vowel productions. Although new research models are still needed to succinctly account for the speech acoustic changes of the elderly, especially for their specific patterns of human vocal tract dimensional changes, this study has innovatively applied the noninvasive and cost-effective AR technology to monitor age-related human oral and pharyngeal lumina changes that have direct consequences for speech production.

scholarly journals Age-related decrease in physical activity and functional fitness among elderly men and women [Corrigendum]

2014 ◽  
pp. 979 ◽  
Author(s):  
Zoran Milanovic ◽  
Sporis ◽  
James ◽  
Sasa Pantelic ◽  
Nebojsa Trajkovic ◽  
...  
Keyword(s):  
Physical Activity ◽  
Functional Fitness ◽  
Elderly Men ◽  
Men And Women ◽  
Age Related

scholarly journals Association between Socioeconomic Status, Physical Health and Need for Long-term Care among the Chinese Elderly

2019 ◽  
Vol 16 (12) ◽  
pp. 2124 ◽  
Author(s):  
Fanlei Kong ◽  
Lingzhong Xu ◽  
Mei Kong ◽  
Shixue Li ◽  
Chengchao Zhou ◽  
...  
Keyword(s):  
Socioeconomic Status ◽  
Physical Health ◽  
Long Term Care ◽  
Elderly Women ◽  
The Elderly ◽  
Elderly Men ◽  
Term Care ◽  
Chinese Elderly ◽  
Men And Women

The aim of this study was to explore the relationship between socioeconomic status (SES), physical health and the need for long-term care (NLTC) of the Chinese elderly, and further, to provide evidence-based advice for establishing an LTC system in China. A cross-sectional survey was conducted in Shandong Province, China in 2017 by using multi-stage random sampling method. Data were collected from elderly individuals aged 60 years and older by self-designed questionnaires through face-to face interviews. A total of 7070 participants were finally included in the database (40.3% male, 59.7% female). Chi-square test analysis and structural equation modeling (SEM) were conducted to clarify the association between SES, physical health and NLTC among the Chinese elderly men and women in Shandong Province. The results of the SEM analysis showed that physical health exerted a strong and negative effect on the NLTC for both genders, with a slightly stronger effect found among the elderly men. SES was found to be significantly and negatively related to the NLTC among the elderly women, while no statistical significance was found for the association between SES and NLTC for elderly men. A significant and positive association between SES and physical health was observed among the elderly men and women, with a slightly stronger effect among the elderly women. Implications for lowering the NLTC and developing an LTC system were addressed based on the findings above.

Reactions to Gifts as Indicators of Personality-Behavior Traits in the Elderly

1974 ◽  
Vol 5 (3) ◽  
pp. 265-280
Author(s):  
Frances M. Carp
Keyword(s):  
Hypothesis Testing ◽  
Public Housing ◽  
The Elderly ◽  
Ego Strength ◽  
Elderly Men ◽  
Behavior Ratings ◽  
Men And Women ◽  
Additional Hypothesis ◽  
Two Populations ◽  
Housing Facilities

Presentation of a token of appreciation to elderly respondents was used as an opportunity to test some hypotheses in regard to the dynamics of giving and receiving. Specific gift-situation reactions which seemed relevant to ego strength, dependency and retentiveness were used to predict scores on more traditional measures of these personality-behavior traits. Two populations of elderly men and women were studied. All were residents of public housing facilities. Correlations of gift-behavior ratings with criterion data collected nine months later confirm that the style in which a gift is received discloses basic personality functions. The findings suggest that the growing necessity to pay or otherwise reciprocate for data may provide opportunity for additional hypothesis testing.

Impaired secretion of growth hormone-releasing hormone, growth hormone and IGF-I in elderly men

1991 ◽  
Vol 124 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Hiroshi Bando ◽  
Chenyu Zhang ◽  
Yukinobu Takada ◽  
Ryuichi Yamasaki ◽  
Shiro Saito
Keyword(s):  
Growth Hormone ◽  
Young Men ◽  
The Elderly ◽  
Elderly Group ◽  
Elderly Men ◽  
Age Related ◽  
Igf I ◽  
Basal Plasma ◽  
Plasma Gh ◽  
Ghrh Test

Abstract. The GHRH test and L-dopa test were performed in 12 normal young men (24.1 ± 1.1 years) and 12 normal elderly men (77.8±1.4 years) to investigate age-related changes in secretion of GHRH, GH and IGF-I. The basal plasma levels of GHRH and GH were not significantly different in young and elderly men, but the basal plasma level of IGF-I was higher in the young men (159.0± 11.7 vs 86.7± 11.6 μg/1). The area under the curve for plasma GH in the GHRH test was less in the elderly group (35.1 ±5.9 vs 11.2 ± 2.1 μg · h−1 · 1−1, p<0.001). The AUCs for the plasma GHRH and GH responses in the L-dopa test in young and elderly men were 32.0±2.7 vs 20.3±1.8 ng · h−1 · 1−1 (p<0.001), and 21.8±4.6 vs 5.4±1.1 μg · h−1 · 1 (p<0.01), respectively, indicating decreased releases of GHRH and GH in the elderly. Correlations between the AUCs for plasma GHRH and GH responses in L-dopa were found in both groups, but the ratio of the AUCs for GH/GHRH was lower in the elderly group. The elderly group showed a significant correlation between the basal plasma IGF-I level and the AUCs for plasma GH in the GHRH and L-dopa tests. These results suggest that elderly men have a decreased reserve of hypothalamic GHRH, resulting in secondarily impaired GH release, which may lead to a lower level of IGF-I than in young men.

scholarly journals Age-related decrease in physical activity and functional fitness among elderly men and women

2013 ◽  
pp. 549 ◽  
Author(s):  
Zoran Milanovic ◽  
Bojan Jorgić ◽  
Nebojša Trajković ◽  
Sporis ◽  
Saša Pantelić ◽  
...  
Keyword(s):  
Physical Activity ◽  
Functional Fitness ◽  
Elderly Men ◽  
Men And Women ◽  
Age Related

Neuroendocrine rhythms and sleep in aging men

1991 ◽  
Vol 260 (4) ◽  
pp. E651-E661 ◽  
Author(s):  
A. van Coevorden ◽  
J. Mockel ◽  
E. Laurent ◽  
M. Kerkhofs ◽  
M. L'Hermite-Baleriaux ◽  
...  
Keyword(s):  
Young Male ◽  
Extended Period ◽  
The Elderly ◽  
Thyroid Stimulating Hormone ◽  
Temporal Organization ◽  
Elderly Subjects ◽  
Elderly Men ◽  
Age Related ◽  
Aging Men ◽  
Effects Of Aging

To delineate the physiological effects of aging on basal levels and temporal patterns of neuroendocrine secretions, the 24-h profiles of cortisol, thyroid-stimulating hormone (TSH), melatonin, prolactin, and growth hormone (GH) levels were simultaneously obtained at frequent intervals in eight healthy, active elderly men, age 67-84 yr and in eight young male adults, age 20-27 yr. The study was preceded by an extended period of habituation to laboratory conditions, and sleep was polygraphically recorded. Mean cortisol levels in the elderly were normal, but the amplitude of the circadian rhythm was reduced. Circulating levels of daytime and nighttime levels of both TSH and GH were greatly diminished in old age. In contrast, prolactin and melatonin concentrations were decreased during the nighttime only. The circadian rises of cortisol, TSH, and melatonin occurred 1-1.5 h earlier in elderly subjects, and the distribution of rapid-eye-movement stages during sleep was similarly advanced, suggesting that circadian timekeeping is modified during normal senescence. Despite perturbations of sleep, sleep-related release of GH and prolactin occurred in all elderly men. Age-related decreases in hormonal levels were associated with a decrease in the amplitude, but not the frequency, of secretory pulses. These findings demonstrate that the normal process of aging involves alterations in the central mechanisms controlling the temporal organization of endocrine release in addition to a reduction of secretory outputs.

Effect of age on dopaminergic responses to protein feeding

1995 ◽  
Vol 268 (4) ◽  
pp. F613-F625
Author(s):  
N. K. Fukagawa ◽  
L. G. Bandini ◽  
M. A. Lee ◽  
J. B. Young
Keyword(s):  
Young Men ◽  
Elderly Men ◽  
Aldosterone Secretion ◽  
Water Excretion ◽  
Age Related ◽  
Serum Aldosterone ◽  
Protein Feeding ◽  
Old Men ◽  
Induced Changes ◽  
Effect Of Age

Renal excretory responses to protein feeding were compared in nine young (20-26 yr) and nine elderly (70-89 yr) men. Although protein increased excretion of dopamine and serotonin (5-HT, P < 0.001 for both), the basal excretion of dopamine and 5-HT was less in old than young men (P < 0.05). Protein increased sodium and water excretion in the young; responses in elderly for both were less (P < 0.025). Carbidopa markedly suppressed dopamine and 5-HT excretion in both young and old men. Carbidopa also attenuated protein-induced natriuresis and diuresis and raised serum aldosterone levels in the young but not in the old men. These age-related differences in dopamine and 5-HT excretion were not abolished by alterations in dietary NaCl. Thus, although dopamine excretion is decreased overall in elderly men, sodium and water excretion and aldosterone secretion in the old men were unaffected by alterations in dopamine production. These data suggest that impaired protein-induced natriuresis in the old men may be due to limitations in renovascular responses and that, in young men, dopamine and 5-HT may contribute to the protein-induced changes in renovascular function.

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