Near-infrared spectroscopy detects age-related differences in skeletal muscle oxidative function: promising implications for geroscience

Age is the greatest risk factor for chronic disease and is associated with a marked decline in functional capacity and quality of life. A key factor contributing to loss of function in older adults is the decline in skeletal muscle function. While the exact mechanism(s) remains incompletely understood, age-related mitochondrial dysfunction is thought to play a major role. To explore this question further, we studied 15 independently living seniors (age: 72 ± 5 years; m/f: 4/11; BMI: 27.6 ± 5.9) and 17 young volunteers (age: 25 ± 4 years; m/f: 8/9; BMI: 24.0 ± 3.3). Skeletal muscle oxidative function was measured in forearm muscle from the recovery kinetics of muscle oxygen consumption using near-infrared spectroscopy (NIRS). Muscle oxygen consumption was calculated as the slope of change in hemoglobin saturation during a series of rapid, supra-systolic arterial cuff occlusions following a brief bout of exercise. Aging was associated with a significant prolongation of the time constant of oxidative recovery following exercise (51.8 ± 5.4 sec vs. 37.1 ± 2.1 sec, P = 0.04, old vs. young, respectively). This finding suggests an overall reduction in mitochondrial function with age in nonlocomotor skeletal muscle. That these data were obtained using NIRS holds great promise in gerontology for quantitative assessment of skeletal muscle oxidative function at the bed side or clinic

Relationship between engagement and level of functional status in older adults

Functional status is an important component of quality of life for older adults and for their caregivers. Factors associated with level of functional status include age, comorbidity, cognitive status, depression, social support, and activity. Of the types of activity linked with functional status, the strongest evidence is for physical exercise, with weaker evidence for social and productive activity. Engagement is a construct including motivation, commitment, and participation. Objective: The objective of this study was to determine whether or not engagement is associated with level of functional status after controlling for age, comorbidity, and depression among older adults. Methods: In all, 92 older adults were recruited from senior living centers and a university-based senior exercise group. The main independent variable was engagement. Other independent variables were age, comorbidity, and depression. The dependent variable was level of functional status. Two different measures of level of functional status were used: the Katz Activities of Daily Living Index and the Lawton–Brody Instrumental Activities of Daily Living Scale. Results: Engagement was a significant predictor of Lawton–Brody Instrumental Activities of Daily Living Scale level of function in the Lawton–Brody model (odds ratio: 1.147 (1.011–1.302)) and age was a significant negative predictor (odds ratio: 0.838 (0.769–0.914)). There were no significant predictors in the Katz model. Conclusion: Engagement is a significant predictor of perfect Lawton–Brody Instrumental Activities of Daily Living Scale score after controlling for age, comorbidity, and depression. Health-care professionals should consider including engagement in their assessment of older clients, whether using formal instruments such as the Engagement with Meaningful Activity Survey or assessing informally

Near-infrared spectroscopy detects age-related differences in skeletal muscle oxidative function: promising implications for geroscience

Age is the greatest risk factor for chronic disease and is associated with a marked decline in functional capacity and quality of life. A key factor contributing to loss of function in older adults is the decline in skeletal muscle function. While the exact mechanism(s) remains incompletely understood, age-related mitochondrial dysfunction is thought to play a major role. To explore this question further, we studied 15 independently living seniors (age: 72 ± 5 years; m/f: 4/11; BMI: 27.6 ± 5.9) and 17 young volunteers (age: 25 ± 4 years; m/f: 8/9; BMI: 24.0 ± 3.3). Skeletal muscle oxidative function was measured in forearm muscle from the recovery kinetics of muscle oxygen consumption using near-infrared spectroscopy (NIRS). Muscle oxygen consumption was calculated as the slope of change in hemoglobin saturation during a series of rapid, supra-systolic arterial cuff occlusions following a brief bout of exercise. Aging was associated with a significant prolongation of the time constant of oxidative recovery following exercise (51.8 ± 5.4 sec vs. 37.1 ± 2.1 sec, P = 0.04, old vs. young, respectively). This finding suggests an overall reduction in mitochondrial function with age in nonlocomotor skeletal muscle. That these data were obtained using NIRS holds great promise in gerontology for quantitative assessment of skeletal muscle oxidative function at the bed side or clinic

Natural resource governance in light of the 2030 Agenda: The case of competition for groundwater in Azraq, Jordan

This study analyses a complex social-ecological system (SES), the case of competition for groundwater in Azraq, in the light of the 2030 Agenda. Building on the Institutional Analysis and Development Framework (IAD) and the concept of Networks of Adjacent Action Situations (NAAS) it assess the complex governance system in a consistent and systematic manner. It includes aspects of power through the political economy concept of the social contract. It furthermore assesses the performance of the investigated SES against the 2030 Agenda's core principles 'leaving no one behind', 'interconnectedness and indivisibility', 'multi-stakeholder partnerships', and 'inclusiveness'. The study finds that in Azraq, agricultural, domestic and environmental water users compete for shrinking groundwater resources. The core of the conflict lies between a heterogeneous group of farmers, who use groundwater for irrigation agriculture supported by a strong political lobby, and the water authorities, which rely on the aquifer for domestic water supply at national level. Water, agricultural, environmental, energy, and land governance, but also high-level decision-making and the monarchy's underlying social contract and the informal concept of wasta influence the outcomes on the ground. As a result, groundwater governance in Jordan hardly does justice to the 2030 Agenda's core principles. The study shows that no panacea exists, but that systems thinking may help identify a range of intervention points, some more sensitive than others, that could support a social-ecological transformation towards sustainability

Acute Skin Damage and Late Radiation-Induced Fibrosis and Inflammation in Murine Ears after High-Dose Irradiation

The use of different scoring systems for radiation-induced toxicity limits comparability between studies. We examined dose-dependent tissue alterations following hypofractionated X-ray irradiation and evaluated their use as scoring criteria. Four dose fractions (0, 5, 10, 20, 30 Gy/fraction) were applied daily to ear pinnae. Acute effects (ear thickness, erythema, desquamation) were monitored for 92 days after fraction 1. Late effects (chronic inflammation, fibrosis) and the presence of transforming growth factor beta 1 (TGFβ1)-expressing cells were quantified on day 92. The maximum ear thickness displayed a significant positive correlation with fractional dose. Increased ear thickness and erythema occurred simultaneously, followed by desquamation from day 10 onwards. A significant dose-dependency was observed for the severity of erythema, but not for desquamation. After 4 × 20 and 4 × 30 Gy, inflammation was significantly increased on day 92, whereas fibrosis and the abundance of TGFβ1-expressing cells were only marginally increased after 4 × 30 Gy. Ear thickness significantly correlated with the severity of inflammation and fibrosis on day 92, but not with the number of TGFβ1-expressing cells. Fibrosis correlated significantly with inflammation and fractional dose. In conclusion, the parameter of ear thickness can be used as an objective, numerical and dose-dependent quantification criterion to characterize the severity of acute toxicity and allow for the prediction of late effects