The Relationships Among Age, Physical Activity, and Working Memory

As our population ages, determining exogenous factors that may offset cognitive decline become increasingly important. The primary goal of the present study was to determine whether older individuals who engage in regular physical activity demonstrate superior working memory performance relative to older sedentary individuals. Forty young (20 active, 20 sedentary) and forty older (20 active, 20 sedentary) individuals engaged in cognitive measures of information processing speed, inhibitory function, and verbal and visuospatial working memory. Age differences in recall were found for verbal and visuospatial span tasks, as well as for recall reaction time on verbal and visuospatial n-back tasks, and age-related performance decrements were exacerbated in the most difficult task conditions. All participants performed less accurately and took longer to respond to stimuli as the verbal and visuospatial n-back tasks became more difficult. A second objective was to examine the effects of age and physical activity on frontal midline theta and hemispheric alpha, as a function of verbal and visuospatial n-back task difficulty. Frontal midline theta recorded at Fz increased for all participants as taskload increased for the verbal, but not visuospatial n-back task. However, as the visuospatial task became more difficult, the younger group showed a greater increase in frontal midline theta than the older group. Neither age, physical activity, nor taskload had an effect on frontal and parietal alpha asymmetry as analyzed from recordings at F3, F4, P3, and P4. The third objective was to evaluate the degree to which physical activity was related to information processing speed and inhibitory function in older adults, as these two constructs are associated with working memory. Cognitive processing speed, attention accuracy, and attention reaction time were all influenced by age. The hypothesized interaction between age and physical activity was not observed for any of the behavioral nor physiological measurements. Several possible explanations for why the main predictions were not supported are discussed, including the idea that it may be physical fitness, rather than physical activity, which contributes to healthy adult brain aging

Developmental expression of REGA-1, a regionally expressed glial antigen in the central nervous system of grasshopper embryos

Journal ArticleGlial cells are a large component of the developing nervous system, appearing before the onset of axon outgrowth in a variety of developing systems. Their time of appearance and their location in conjunction with developing axon pathways may allow them to define the position of axon pathways

A Complex Interaction Between Reduced Reelin Expression and Prenatal Organophosphate Exposure Alters Neuronal Cell Morphology.

Genetic and environmental factors are both likely to contribute to neurodevelopmental disorders including schizophrenia, autism spectrum disorders, and major depressive disorders. Prior studies from our laboratory and others have demonstrated that the combinatorial effect of two factors-reduced expression of reelin protein and prenatal exposure to the organophosphate pesticide chlorpyrifos oxon-gives rise to acute biochemical effects and to morphological and behavioral phenotypes in adolescent and young adult mice. In the current study, we examine the consequences of these factors on reelin protein expression and neuronal cell morphology in adult mice. While the cell populations that express reelin in the adult brain appear unchanged in location and distribution, the levels of full length and cleaved reelin protein show persistent reductions following prenatal exposure to chlorpyrifos oxon. Cell positioning and organization in the hippocampus and cerebellum are largely normal in animals with either reduced reelin expression or prenatal exposure to chlorpyrifos oxon, but cellular complexity and dendritic spine organization is altered, with a skewed distribution of immature dendritic spines in adult animals. Paradoxically, combinatorial exposure to both factors appears to generate a rescue of the dendritic spine phenotypes, similar to the mitigation of behavioral and morphological changes observed in our prior study. Together, our observations support an interaction between reelin expression and chlorpyrifos oxon exposure that is not simply additive, suggesting a complex interplay between genetic and environmental factors in regulating brain morphology

Carboxyl-modified single-wall carbon nanotubes improve bone tissue formation in vitro and repair in an in vivo rat model.

The clinical management of bone defects caused by trauma or nonunion fractures remains a challenge in orthopedic practice due to the poor integration and biocompatibility properties of the scaffold or implant material. In the current work, the osteogenic properties of carboxyl-modified single-walled carbon nanotubes (COOH-SWCNTs) were investigated in vivo and in vitro. When human preosteoblasts and murine embryonic stem cells were cultured on coverslips sprayed with COOH-SWCNTs, accelerated osteogenic differentiation was manifested by increased expression of classical bone marker genes and an increase in the secretion of osteocalcin, in addition to prior mineralization of the extracellular matrix. These results predicated COOH-SWCNTs' use to further promote osteogenic differentiation in vivo. In contrast, both cell lines had difficulties adhering to multi-walled carbon nanotube-based scaffolds, as shown by scanning electron microscopy. While a suspension of SWCNTs caused cytotoxicity in both cell lines at levels >20 μg/mL, these levels were never achieved by release from sprayed SWCNTs, warranting the approach taken. In vivo, human allografts formed by the combination of demineralized bone matrix or cartilage particles with SWCNTs were implanted into nude rats, and ectopic bone formation was analyzed. Histological analysis of both types of implants showed high permeability and pore connectivity of the carbon nanotube-soaked implants. Numerous vascularization channels appeared in the formed tissue, additional progenitor cells were recruited, and areas of de novo ossification were found 4 weeks post-implantation. Induction of the expression of bone-related genes and the presence of secreted osteopontin protein were also confirmed by quantitative polymerase chain reaction analysis and immunofluorescence, respectively. In summary, these results are in line with prior contributions that highlight the suitability of SWCNTs as scaffolds with high bone-inducing capabilities both in vitro and in vivo, confirming them as alternatives to current bone-repair therapies

Patient active time during therapy sessions in postacute rehabilitation: Development and validation of a new measure

BACKGROUND AND PURPOSE: The accurate measurement of therapy intensity in postacute rehabilitation is important for research to improve outcomes in this setting. We developed and validated a measure of Patient Active Time during physical (PT) and occupational therapy (OT) sessions, as a proxy for therapy intensity. METHODS: This measurement validity study was carried out with 26 older adults admitted to a skilled nursing facility (SNF) for postacute rehabilitation with a variety of main underlying diagnoses, including hip fracture, cardiovascular diseases, stroke, and others. They were participants in a randomized controlled trial that compared an experimental high-intensity therapy to standard-of-care therapy. Patient Active Time was observed by research raters as the total number of minutes that a patient was actively engaging in therapeutic activities during PT and OT sessions. This was compared to patient movement (actigraphy) quantified during some of the same PT/OT sessions using data from three-dimensional accelerometers worn on the patient’s extremities. RESULTS: Activity measures were collected for 136 therapy sessions. Patient Active Time had high interrater reliability in both PT (r = 0.995, p < 0.001) and OT (r = 0.95, p = 0.012). Active time was significantly correlated with actigraphy in both PT (r = 0.73, p < 0.001) and OT (r = 0.60, p < 0.001) and discriminated between a high-intensity experimental condition and standard of care rehabilitation: in PT, 47.0 ± 13.5 min versus 16.7 ± 10.1 min (p < 0.001) and in OT, 46.2 ± 15.2 versus 27.7 ± 6.6 min (p < 0.001). CONCLUSIONS: Systematic observation of Patient Active Time provides an objective, reliable, and valid index of physical activity during PT and OT treatment sessions that has utility as a real-world alternative to the measurement of treatment intensity. This measure could be used to differentiate higher from lower therapy treatment intensity and to help determine the optimal level of active therapy time for patients in postacute and other settings

Early effects of lipopolysaccharide-induced inflammation on foetal brain development in rat

Studies in humans and animal models link maternal infection and imbalanced levels of inflammatory mediators in the foetal brain to the aetiology of neuropsychiatric disorders. In a number of animal models, it was shown that exposure to viral or bacterial agents during a period that corresponds to the second trimester in human gestation triggers brain and behavioural abnormalities in the offspring. However, little is known about the early cellular and molecular events elicited by inflammation in the foetal brain shortly after maternal infection has occurred. In this study, maternal infection was mimicked by two consecutive intraperitoneal injections of 200 μg of LPS (lipopolysaccharide)/kg to timed-pregnant rats at GD15 (gestational day 15) and GD16. Increased thickness of the CP (cortical plate) and hippocampus together with abnormal distribution of immature neuronal markers and decreased expression of markers for neural progenitors were observed in the LPS-exposed foetal forebrains at GD18. Such effects were accompanied by decreased levels of reelin and the radial glial marker GLAST (glial glutamate transporter), and elevated levels of pro-inflammatory cytokines in maternal serum and foetal forebrains. Foetal inflammation elicited by maternal injections of LPS has discrete detrimental effects on brain development. The early biochemical and morphological changes described in this work begin to explain the sequelae of early events that underlie the neurobehavioural deficits reported in humans and animals exposed to prenatal insults

Female Sexual Function Index Short Version: A MsFLASH Item Response Analysis

The Female Sexual Function Index (FSFI) is a psychometrically sound and popular 19-item self-report measure, but its length may preclude its use in studies with multiple outcome measures, especially when sexual function is not a primary endpoint. Only one attempt has been made to create a shorter scale, resulting in the Italian FSFI-6, later translated into Spanish and Korean without further psychometric analysis. Our study evaluated whether a subset of items on the 19-item English-language FSFI would perform as well as the full-length FSFI in peri- and post-menopausal women. We used baseline data from 898 peri- and post-menopausal women recruited from multiple communities, ages 42–62 years, and enrolled in randomized controlled trials for vasomotor symptom management. Goals were to (1) create a psychometrically sound, shorter version of the FSFI for use in peri- and post-menopausal women as a continuous measure and (2) compare it to the Italian FSFI-6. Results indicated that a 9-item scale provided more information than the FSFI-6 across a spectrum of sexual functioning, was able to capture sample variability, and showed sufficient range without floor or ceiling effects. All but one of the items from the Italian 6-item version were included in the 9-item version. Most omitted FSFI items focused on frequency of events or experiences. When assessment of sexual function is a secondary endpoint and subject burden related to questionnaire length is a priority, the 9-item FSFI may provide important information about sexual function in English-speaking peri- and post-menopausal women

Efficacy of yoga for vasomotor symptoms: a randomized controlled trial

OBJECTIVE: This study aims to determine the efficacy of yoga in alleviating vasomotor symptoms (VMS) frequency and bother. METHODS: This study was a three-by-two factorial, randomized controlled trial. Eligible women were randomized to yoga (n = 107), exercise (n = 106), or usual activity (n = 142), and were simultaneously randomized to a double-blind comparison of ω-3 fatty acid (n = 177) or placebo (n = 178) capsules. Yoga intervention consisted of 12 weekly 90-minute yoga classes with daily home practice. Primary outcomes were VMS frequency and bother assessed by daily diaries at baseline, 6 weeks, and 12 weeks. Secondary outcomes included insomnia symptoms (Insomnia Severity Index) at baseline and 12 weeks. RESULTS: Among 249 randomized women, 237 (95%) completed 12-week assessments. The mean baseline VMS frequency was 7.4 per day (95% CI, 6.6 to 8.1) in the yoga group and 8.0 per day (95% CI, 7.3 to 8.7) in the usual activity group. Intent-to-treat analyses included all participants with response data (n = 237). There was no difference between intervention groups in the change in VMS frequency from baseline to 6 and 12 weeks (mean difference [yoga--usual activity] from baseline at 6 wk, -0.3 [95% CI, -1.1 to 0.5]; mean difference [yoga--usual activity] from baseline at 12 wk, -0.3 [95% CI, -1.2 to 0.6]; P = 0.119 across both time points). Results were similar for VMS bother. At week 12, yoga was associated with an improvement in insomnia symptoms (mean difference [yoga - usual activity] in the change in Insomnia Severity Index, 1.3 [95% CI, -2.5 to -0.1]; P = 0.007). CONCLUSIONS: Among healthy women, 12 weeks of yoga class plus home practice, compared with usual activity, do not improve VMS frequency or bother but reduce insomnia symptoms

Menopausal Quality of Life: A RCT of Yoga, Exercise and Omega-3 Supplements

Objective— Determine efficacy of three non-hormonal therapies for improving menopause- related quality of life (QOL) in women with vasomotor symptoms (VMS). Methods— 12-week 3×2 randomized, controlled, factorial design trial. Peri- and postmenopausal women, ages 40-62 years, were randomized to yoga (n=107), exercise (n=106), or usual activity (n=142), and also randomized to double-blind comparison of omega-3 (n=177) or placebo (n=178) capsules. Interventions: 1) weekly 90-minute yoga classes with daily at-home practice; 2) individualized facility-based aerobic exercise training 3 times/week; and 3) 0.615 gram omega-3 supplement, 3 times/day. Outcomes: Menopausal Quality of Life Questionnaire (MENQOL) total and domain (VMS, psychosocial, physical and sexual) scores. Results— Among 355 randomized women, average age 54.7 years, 338 (95%) completed 12- week assessments. Mean baseline VMS frequency was 7.6/day and mean baseline total MENQOL score was 3.8 (range 1-8 from better to worse) with no between-group differences. For yoga compared to usual activity, baseline to 12-week improvements were seen for MENQOL total -0.3 (95% CI -0.6 to 0.0, p=0.02), and VMS (p=0.02) and sexuality (p=0.03) domain scores. For exercise and omega-3 compared to controls, improvements in baseline to 12-week total MENQOL scores were not observed. Exercise showed benefit in the MENQOL physical domain score at 12- weeks (p=0.02). Conclusion— All women become menopausal and many seek medical advice on ways to improve quality of life; little evidence-based information exists. We found, among healthy sedentary menopausal women, yoga appears to improve menopausal QOL - the clinical significance of our finding is uncertain due to modest effect