This study investigated energy expenditure and obstacle course negotiation between the C-leg 1 and various non-microprocessor control (NMC) prosthetic knees and compared a quality of life survey (SF-36v2 TM ) of use of the C-leg 1 to national norms. Thirteen subjects with unilateral limb loss (12 with trans-femoral and one with a knee disarticulation amputation) participated in the study. The mean age was 46 years, range 30 -75. Energy expenditure using both the NMC and C-leg 1 prostheses was measured at self-selected typical and fast walking paces on a motorized treadmill. Subjects were also asked to walk through a standardized walking obstacle course carrying a 4.5 kg (10 lb) basket and with hands free. Finally, the SF-36v2 TM was completed for subjects while using the C-leg 1 . Statistically significant differences were found in oxygen consumption between prostheses at both typical and fast paces with the C-leg 1 showing decreased values. Use of the C-leg 1 resulted in a statistically significant decrease in the number of steps and time to complete the obstacle course. Scores on a quality of life index for subjects using the C-leg 1 were above the mean for norms for limitation in the use of an arm or leg, equal to the mean for the general United States population for the physical component score and were above this mean for the mental component score. Based on oxygen consumption and obstacle course findings, the C-leg 1 when compared to the NMC prostheses may provide increased functional mobility and ease of performance in the home and community environment. Questionnaire results suggest a minimal quality of life impairment when using a C-leg 1 for this cohort of individuals with amputation.

Objective To assess domains of social determinants of health (SDoH) and their associations with cognition and quality of life. Method This investigation uses baseline data from individuals participating in the ACTIVE trial ( n = 2505) to reproduce the SDoH domains described in Healthy People 2030 (economic stability, health care, education, neighborhood and built environment, and social and community context). Results: Results support using data from the ACTIVE trial to assess all five SDoH domains, and the ability of the composites to predict baseline performance on measures of cognition and self-reported quality of life within a sample of older adults. Additionally, higher SDoH domain scores were associated with better functioning on composite measures of cognition and higher scores for mental and physical health-related quality of life with Access to Healthcare associated with all outcomes. Discussion: These findings can inform investigators interested in assessing multiple domains of SDoH and highlight the importance of access to health care within older Black/African American and White older adults.

Chronic opiate exposure induces neuroadaptations in the mesocorticolimbic system including ventral tegmental area (VTA) dopamine (DA) neurons, whose soma size is decreased following opiate exposure. Yet it is now well documented that VTA DA neurons are heterogeneous, with notable differences between VTA DA neurons based on their projection target. Therefore, we sought to determine whether chronic morphine induced similar changes in the morphology of VTA DA neurons that project to the nucleus accumbens (NAc) and prefrontal cortex (PFC). We utilized Cre-dependent retrograde viral vectors in DA Cre driver lines to label VTA DA neurons that projected to NAc and PFC and assessed neuronal soma size. Consistent with previous data, the soma size of VTA DA neurons that projected to the NAc medial shell was decreased following morphine exposure. However, soma size of VTA DA neurons that projected to the NAc core was unaltered by morphine. Interestingly, morphology of PFC-projecting VTA DA neurons was also altered by morphine, but in this case soma size was increased compared to sham controls. Differences in basal soma size were also noted, suggesting stable differences in projection-specific morphology in addition to drug-induced changes. Together, these data suggest morphine-induced changes in VTA DA morphology occur within distinct VTA DA populations and that study of opiate-induced structural plasticity of individual VTA DA subcircuits may be critical for understanding addiction-related behavior.Electronic supplementary materialThe online version of this article (10.1186/s13041-019-0435-6) contains supplementary material, which is available to authorized users.

Objective: This study aims to examine indicators of crash risk longitudinally in older adults ( n = 486). Method: This study applied secondary data analyses of the 10 years of follow-up for the ACTIVE study combined with state-recorded crash records from five of the six participating sites. Cox proportional hazards models were first used to examine the effect of each variable of interest at baseline after controlling for miles driven and then to assess the three cognitive composites as predictors of time to at-fault crash in covariate-adjusted models. Results: Older age, male sex, and site location were each predictive of higher crash risk. Additionally, worse scores on the speed of processing cognitive composite were associated with higher crash risk. Discussion: Results support previous findings that both age and male sex are associated with higher crash risk. Our significant finding of site location could be attributed to the population density of our testing sites and transportation availability.

The ability to drive a vehicle is an everyday function that helps older adults maintain independence. Few observational studies have examined the relationship between cognitive decline and driving mobility and in context of racial differences and social determinants of health (SDOH). To address this empirical gap, this study aimed to characterize how cognitive functioning is longitudinally associated with driving mobility (driving space, driving exposure, and driving difficulty) in older age, and how it may vary by race and SDOH. Using the control arm of the Advanced Cognitive Training in Vital Elderly study (n=581, 24.5% Black), multilevel models examined longitudinal associations between processing speed, visual attention, memory, and reasoning with driving mobility outcomes. Race and SDOH moderations were explored. Only declines in reasoning and processing speed related to driving mobility, moderated by race and SDOH. Reasoning decline related to increased driving space in White (β=-.21,p=.006) but not Black older adults (p=.286). Processing speed decline related to greater driving exposure in Black older adults (β=-.15,p < .001) but less driving exposure in White older adults (β=.13,p=.006). Processing speed decline related to reduced driving exposure (β=-.06,p=.001) and increased driving difficulty (β=-.35,p < .001), but only in people living in poorer neighborhood and built environment and poorer social community contexts, respectively. Overall, findings emphasize that relationships between cognitive decline and driving mobility are dependent on race and SDOH. Consideration of such factors may help target those in greatest need to sustain safe driving mobility and functional independence.