114 research outputs found

    Neuroprotective Effects of Cardiorespiratory Fitness on White Matter Integrity and Cognition Across the Adult Lifespan

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    Objective: Cardiorespiratory fitness (CRF) is associated with decreased risk for cognitive decline. Accumulating evidence has linked CRF to more conserved white matter (WM) integrity and better cognitive performance in older adults. Additional research is needed to determine: (1) which WM tracts are most strongly related to CRF, (2) whether CRF-related benefits on WM translate to enhanced executive functioning (EF), and (3) if the neuroprotective effects of CRF are age-dependent. This study aimed to evaluate CRF as an intervention for modulating decreased WM integrity and EF in aging. Method: Participants were community-dwelling adults (N = 499; ages 20-85) from the open-access Nathan Kline Institute – Rockland Sample (NKIRS) with CRF (bike test), self-report of physical activity, diffusion tensor imaging (DTI), and EF data. Mixed-effect modeling tested the interaction between CRF and age on WM integrity (global and local microstructure). Significant WM tracts were retained for structural equation modeling to determine whether enhanced microstructure mediated a positive relationship between CRF and EF. Results: Among older participants (age 60), CRF was significantly related to stronger whole-brain (z-score slope = 0.11) and local WM integrity within five tracts (z-score slope range = 0.14 – 0.20). In support of the age-dependent hypothesis, the CRF–WM relationship was comparably weaker (z-score slopes 0.11) and more limited (one WM tract) in younger adults. CRF was more consistently related to WM than self-report of physical activity. Although CRF was linked to enhanced WM integrity, its potential benefits on EF were not directly observed. Conclusion: The findings highlight the importance of positive lifestyle factors, such as physical activity, in maintaining brain health in senescence. CRF may selectively preserve a collection of anterior and posterior WM connections related to visuomotor function

    Development of a Mind Body Program for Obese Knee Osteoarthritis Patients with Comorbid Depression

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    Knee osteoarthritis (OA) is the most common joint disorder in the U.S. and a leading cause of disability. Depression and obesity are highly comorbid among knee OA patients, and the combination of obesity and depression is associated with decreased physical activity, higher pain and disability, and more rapid cartilage degradation. Depression, obesity and OA exacerbate one another and share a common pathophysiology involving systemic inflammation and pro-inflammatory cytokines, reflecting a complex mind-body interaction. Current treatments for knee OA offer little to no benefit over placebo, and do not emphasize mind-body practices or physical activity to target the underlying pathophysiology. Mind-body interventions to lessen depressive symptoms and increase physical activity offer the ability to target biological, mechanical and psychological mechanisms of OA progression. Our long-term goals are to evaluate the mechanisms by which the Relaxation Response Resiliency Program (3RP) delivered via secure telehealth, and adapted for patients with depression, obesity and knee OA (GetActive-OA) promotes increases in physical activity and improved knee health. We hypothesize that the synergistic interaction between mindfulness, adaptive thinking, positive psychology and healthy living skills of the GetActive-OA will slow the progression of symptomatic knee OA by reducing pro-inflammatory cytokine expression and promoting optimal mechanical loading of the cartilage. Here we present the protocol for a mixed methods study that will adapt the 3RP for the needs of knee OA patients with depression and obesity with a focus on increasing physical activity (GetActive-OA), and iteratively maximize the feasibility, credibility and acceptability of the programs and research procedures

    Understanding Barriers and Facilitators to Implementation of Psychosocial Care within Orthopedic Trauma Centers: A Qualitative Study with Multidisciplinary Stakeholders from Geographically Diverse Settings

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    BACKGROUND: Psychosocial factors are pivotal in recovery after acute orthopedic traumatic injuries. Addressing psychosocial factors is an important opportunity for preventing persistent pain and disability. We aim to identify barriers and facilitators to the implementation of psychosocial care within outpatient orthopedic trauma settings using the Consolidated Framework for Implementation Research (CFIR) and Proctor\u27s taxonomy of implementation outcomes, and to provide implementation strategies derived from qualitative data and supplemented by the Expert Recommendations for Implementing Change. METHODS: We conducted live video qualitative focus groups, exit interviews and individual interviews with stakeholders within 3 geographically diverse level 1 trauma settings (N = 79; 20 attendings, 28 residents, 10 nurses, 13 medical assistants, 5 physical therapists/social workers, and 3 fellows) at 3 trauma centers in Texas, Kentucky, and Massachusetts. We used directed and conventional content analyses to derive information on barriers, facilitators, and implementation strategies within 26 CFIR constructs nested within 3 relevant Proctor outcomes of acceptability, appropriateness, and feasibility. RESULTS: Stakeholders noted that implementing psychosocial care within their practice can be acceptable, appropriate, and feasible. Many perceived integrated psychosocial care as crucial for preventing persistent pain and reducing provider burden, noting they lack the time and specialized training to address patients\u27 psychosocial needs. Providers suggested strategies for integrating psychosocial care within orthopedic settings, including obtaining buy-in from leadership, providing concise and data-driven education to providers, bypassing stigma, and flexibly adapting to fast-paced clinics. CONCLUSIONS: Results provide a blueprint for successful implementation of psychosocial care in orthopedic trauma settings, with important implications for prevention of persistent pain and disability

    Cues and knowledge structures used by mental-health professionals when making risk assessments

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    Background: Research into mental-health risks has tended to focus on epidemiological approaches and to consider pieces of evidence in isolation. Less is known about the particular factors and their patterns of occurrence that influence clinicians’ risk judgements in practice. Aims: To identify the cues used by clinicians to make risk judgements and to explore how these combine within clinicians’ psychological representations of suicide, self-harm, self-neglect, and harm to others. Method: Content analysis was applied to semi-structured interviews conducted with 46 practitioners from various mental-health disciplines, using mind maps to represent the hierarchical relationships of data and concepts. Results: Strong consensus between experts meant their knowledge could be integrated into a single hierarchical structure for each risk. This revealed contrasting emphases between data and concepts underpinning risks, including: reflection and forethought for suicide; motivation for self-harm; situation and context for harm to others; and current presentation for self-neglect. Conclusions: Analysis of experts’ risk-assessment knowledge identified influential cues and their relationships to risks. It can inform development of valid risk-screening decision support systems that combine actuarial evidence with clinical expertise

    Effectiveness of insecticide-treated bednets in malaria prevention in Haiti: a case-control study

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    Background Insecticide-treated bednets (ITNs) are eff ective in preventing malaria where vectors primarily bite indoors and late at night, but their eff ectiveness is uncertain where vectors bite outdoors and earlier in the evening. We studied the eff ectiveness of ITNs following a mass distribution in Haiti from May to September, 2012, where the Anopheles albimanus vector bites primarily outdoors and often when people are awake. Methods In this case-control study, we enrolled febrile patients presenting to outpatient departments at 17 health facilities throughout Haiti from Sept 4, 2012, to Feb 27, 2014, who were tested with malaria rapid diagnostic tests (RDTs), and administered questionnaires on ITN use and other risk factors. Cases were defi ned by positive RDT and controls were febrile patients from the same clinic with a negative RDT. Our primary analysis retrospectively matched cases and controls by age, sex, location, and date, and used conditional logistic regression on the matched sample. A sensitivity analysis used propensity scores to match patients on ITN use propensity and analyse malaria among ITN users and non-users. Additional ITN bioeffi cacy and entomological data were collected. Findings We enrolled 9317 patients, including 378 (4%) RDT-positive cases. 1202 (13%) patients reported ITN use. Post-hoc matching of cases and controls yielded 362 cases and 1201 matched controls, 19% (333) of whom reported consistent campaign net use. After using propensity scores to match on consistent campaign ITN use, 2298 patients, including 138 (7%) RDT-positive cases, were included: 1149 consistent campaign ITN users and 1149 non-consistent campaign ITN users. Both analyses revealed that ITNs did not signifi cantly protect against clinical malaria (odds ratio [OR]=0·95, 95% CI 0·68–1·32, p=0·745 for case-control analysis; OR=0·95, 95% CI 0·45–1·97, p=0·884 for propensity score analysis). ITN and entomological data indicated good ITN physical integrity and bioeffi cacy, and no permethrin resistance among local mosquitoes. Interpretation We found no evidence that mass ITN campaigns reduce clinical malaria in this observational study in Haiti; alternative malaria control strategies should be prioritised

    The Mass-Metallicity Relation of a z ~ 2 Protocluster with MOSFIRE

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    We present Keck/MOSFIRE observations of the role of environment in the formation of galaxies at z ~ 2. Using K-band spectroscopy of Hα and [N ii] emission lines, we have analyzed the metallicities of galaxies within and around a z = 2.3 protocluster discovered in the HS1700+643 field. Our main sample consists of 23 protocluster and 20 field galaxies with estimates of stellar masses and gas-phase metallicities based on the N2 strong-line metallicity indicator. With these data we have examined the mass–metallicity relation with respect to environment at z ~ 2. We find that field galaxies follow the well-established trend between stellar mass and metallicity, such that more massive galaxies have larger metallicities. The protocluster galaxies, however, do not exhibit a dependence of metallicity on mass, with the low-mass protocluster galaxies showing an enhancement in metallicity compared to field galaxies spanning the same mass range. A comparison with galaxy formation models suggests that the mass-dependent environmental trend we observed can be qualitatively explained in the context of the recycling of "momentum-driven" galaxy wind material. Accordingly, winds are recycled on a shorter timescale in denser environments, leading to an enhancement in metallicity at fixed mass for all but the most massive galaxies. Future hydrodynamical simulations of z ~ 2 overdensities matching the one in the HS1700 field will be crucial for understanding the origin of the observed environmental trend in detail

    The Lyα Properties of Faint Galaxies at z ~ 2-3 with Systemic Redshifts and Velocity Dispersions from Keck-MOSFIRE

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    We study the Lyα profiles of 36 spectroscopically detected Lyα-emitters (LAEs) at z ~ 2-3, using Keck MOSFIRE to measure systemic redshifts and velocity dispersions from rest-frame optical nebular emission lines. The sample has a median optical magnitude R = 26.0, and ranges from R ≃ 23 to R > 27, corresponding to rest-frame UV absolute magnitudes M _(UV) ≃ –22 to M ^(UV) > –18.2. Dynamical masses range from M_(dyn) 3σ significance: brighter galaxies with larger velocity dispersions tend to have larger values of Δv Lyα. We also make use of a comparison sample of 122 UV-color-selected R < 25.5 galaxies at z ~ 2, all with Lyα emission and systemic redshifts measured from nebular emission lines. Using the combined LAE and comparison samples for a total of 158 individual galaxies, we find that Δv_(Lyα) is anti-correlated with the Lyα equivalent width with 7σ significance. Our results are consistent with a scenario in which the Lyα profile is determined primarily by the properties of the gas near the systemic redshift; in such a scenario, the opacity to Lyα photons in lower mass galaxies may be reduced if large gaseous disks have not yet developed and if the gas is ionized by the harder spectrum of young, low metallicity stars

    Mechanisms of hypoxic up-regulation of versican gene expression in macrophages

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    Hypoxia is a hallmark of many pathological tissues. Macrophages accumulate in hypoxic sites and up-regulate a range of hypoxia-inducible genes. The matrix proteoglycan versican has been identified as one such gene, but the mechanisms responsible for hypoxic induction are not fully characterised. Here we investigate the up-regulation of versican by hypoxia in primary human monocyte-derived macrophages (HMDM), and, intriguingly, show that versican mRNA is up-regulated much more highly (&gt;600 fold) by long term hypoxia (5 days) than by 1 day of hypoxia (48 fold). We report that versican mRNA decay rates are not affected by hypoxia, demonstrating that hypoxic induction of versican mRNA is mediated by increased transcription. Deletion analysis of the promoter identified two regions required for high level promoter activity of luciferase reporter constructs in human macrophages. The hypoxia-inducible transcription factor HIF-1 has previously been implicated as a key potential regulator of versican expression in hypoxia, however our data suggest that HIF-1 up-regulation is unlikely to be principally responsible for the high levels of induction observed in HMDM. Treatment of HMDM with two distinct specific inhibitors of Phosphoinositide 3-kinase (PI3K), LY290042 and wortmannin, significantly reduced induction of versican mRNA by hypoxia and provides evidence of a role for PI3K in hypoxic up-regulation of versican expression

    Conservation Genetics of a Critically Endangered Limpet Genus and Rediscovery of an Extinct Species

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    A third of all known freshwater mollusk extinctions worldwide have occurred within a single medium-sized American drainage. The Mobile River Basin (MRB) of Alabama, a global hotspot of temperate freshwater biodiversity, was intensively industrialized during the 20(th) century, driving 47 of its 139 endemic mollusk species to extinction. These include the ancylinid limpet Rhodacmea filosa, currently classified as extinct (IUCN Red List), a member of a critically endangered southeastern North American genus reduced to a single known extant population (of R. elatior) in the MRB.We document here the tripling of known extant populations of this North American limpet genus with the rediscovery of enduring Rhodacmea filosa in a MRB tributary and of R. elatior in its type locality: the Green River, Kentucky, an Ohio River Basin (ORB) tributary. Rhodacmea species are diagnosed using untested conchological traits and we reassessed their systematic and conservation status across both basins using morphometric and genetic characters. Our data corroborated the taxonomic validity of Rhodacmea filosa and we inferred a within-MRB cladogenic origin from a common ancestor bearing the R. elatior shell phenotype. The geographically-isolated MRB and ORB R. elatior populations formed a cryptic species complex: although overlapping morphometrically, they exhibited a pronounced phylogenetic disjunction that greatly exceeded that of within-MRB R. elatior and R. filosa sister species.Rhodacmea filosa, the type species of the genus, is not extinct. It persists in a Coosa River tributary and morphometric and phylogenetic analyses confirm its taxonomic validity. All three surviving populations of the genus Rhodacmea merit specific status. They collectively contain all known survivors of a phylogenetically highly distinctive North American endemic genus and therefore represent a concentrated fraction of continental freshwater gastropod biodiversity. We recommend the establishment of a proactive targeted conservation program that may include their captive propagation and reintroduction
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