334 research outputs found

    Meningeal Infiltration of the Spinal Cord by Non-Classically Activated B Cells is Associated with Chronic Disease Course in a Spontaneous B Cell-Dependent Model of CNS Autoimmune Disease

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    We characterized B cell infiltration of the spinal cord in a B cell-dependent spontaneous model of central nervous system (CNS) autoimmunity that develops in a proportion of mice with mutant T and B cell receptors specific for myelin oligodendrocyte glycoprotein. We found that, while males are more likely to develop disease, females are more likely to have a chronic rather than monophasic disease course. B cell infiltration of the spinal cord was investigated by histology and FACs. CD4+ T cell infiltration was pervasive throughout the white and in some cases gray matter. B cells were almost exclusively restricted to the meninges, often in clusters reminiscent of those described in human multiple sclerosis. These clusters were typically found adjacent to white matter lesions and their presence was associated with a chronic disease course. Extensive investigation of these clusters by histology did not identify features of lymphoid follicles, including organization of T and B cells into separate zones, CD35+ follicular dendritic cells, or germinal centers. The majority of cluster B cells were IgD+ with little evidence of class switch. Consistent with this, B cells isolated from the spinal cord were of the naïve/memory CD38hi CD95lo phenotype. Nevertheless, they were CD62Llo and CD80hi compared to lymph node B cells suggesting that they were at least partly activated and primed to present antigen. Therefore, if meningeal B cells contribute to CNS pathology in autoimmunity, follicular differentiation is not necessary for the pathogenic mechanism

    The fluid dynamics of swimming by jumping in copepods

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    Author Posting. © The Authors, 2010. This is the author's version of the work. It is posted here by permission of Royal Society for personal use, not for redistribution. The definitive version was published in Journal of the Royal Society Interface 8 (2011): 1090-1103, doi:10.1098/rsif.2010.0481.Copepods swim either continuously by vibrating their feeding appendages or erratically by repeatedly beating their swimming legs resulting in a series of small jumps. The two swimming modes generate different hydrodynamic disturbances and therefore expose the swimmers differently to rheotactic predators. We developed an impulsive stresslet model to quantify the jump-imposed flow disturbance. The predicted flow consists of two counterrotating viscous vortex rings of similar intensity, one in the wake and one around the body of the copepod. We showed that the entire jumping flow is spatially limited and temporally ephemeral owing to jump-impulsiveness and viscous decay. In contrast, continuous steady swimming generates two well-extended long-lasting momentum jets both in front of and behind the swimmer, as suggested by the well-known steady stresslet model. Based on the observed jump-swimming kinematics of a small copepod Oithona davisae, we further showed that jump-swimming produces a hydrodynamic disturbance with much smaller spatial extension and shorter temporal duration than that produced by a same-size copepod cruising steadily at the same average translating velocity. Hence, small copepods in jumpswimming are much less detectable by rheotactic predators. The present impulsive stresslet model improves a previously published impulsive Stokeslet model that applies only to the wake vortex.This work was supported by National Science Foundation grants NSF OCE-0352284 & IOS-0718506 and an award from WHOI’s Ocean Life Institute to H.J and by grants from the Danish Research Council for independent research and the Niels Bohr Foundation to T.K

    Coexisting Cyclic Parthenogens Comprise a Holocene Species Flock in Eubosmina

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    Background: Mixed breeding systems with extended clonal phases and weak sexual recruitment are widespread in nature but often thought to impede the formation of discrete evolutionary clusters. Thus, cyclic parthenogens, such as cladocerans and rotifers, could be predisposed to ‘‘species problems’ ’ and a lack of discrete species. However, species flocks have been proposed for one cladoceran group, Eubosmina, where putative species are sympatric, and there is a detailed paleolimnological record indicating a Holocene age. These factors make the Eubosmina system suitable for testing the hypotheses that extended clonal phases and weak sexual recruitment inhibit speciation. Although common garden experiments have revealed a genetic component to the morphotypic variation, the evolutionary significance of the morphotypes remains controversial. Methodology/Principal Findings: In the present study, we tested the hypothesis of a single polymorphic species (i.e., mixing occurs but selection maintains genes for morphology) in four northern European lakes where the morphotypes coexist. Our evidence is based on nuclear DNA sequence, mitochondrial DNA sequence, and morphometric analysis of coexisting morphotypes. We found significant genetic differentiation, genealogical exclusivity, and morphometric differentiation for coexisting morphotypes. Conclusions: We conclude that the studied morphotypes represent a group of young species undergoing speciation wit

    Splitting and blaming: The psychic life of neoliberal executive women

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    The aim of the article is to explore the psychic life of executive women under neoliberalism using psychosocial approaches. The article shows how, despite enduring unfair treatment and access to opportunities, many executive women remain emotionally invested in upholding the neoliberal ideal that if one perseveres, one shall be successful, regardless of gender. Drawing on psychosocial approaches, we explore how the accounts given by some executive women of repudiation, as denying gender inequality, and individualization, as subjects completely agentic, are underpinned by the unconscious, intertwined processes of splitting and blaming. Women sometimes split off undesirable aspects of the workplace, which repudiates gender inequality, or blame other women, which individualizes failure and responsibility for change. We explain that splitting and blaming enable some executive women to manage the anxiety evoked from threats to the neoliberal ideal of the workplace. This article thereby makes a contribution to existing postfeminist scholarship by integrating psychosocial approaches to the study of the psychic life of neoliberal executive women, by exploring why they appear unable to engage directly with and redress instances of gender discrimination in the workplace

    Effects on incident reporting after educating residents in patient safety: a controlled study

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    <p>Abstract</p> <p>Background</p> <p>Medical residents are key figures in delivering health care and an important target group for patient safety education. Reporting incidents is an important patient safety domain, as awareness of vulnerabilities could be a starting point for improvements. This study examined effects of patient safety education for residents on knowledge, skills, attitudes, intentions and behavior concerning incident reporting.</p> <p>Methods</p> <p>A controlled study with follow-up measurements was conducted. In 2007 and 2008 two patient safety courses for residents were organized. Residents from a comparable hospital acted as external controls. Data were collected in three ways: 1] questionnaires distributed before, immediately after and three months after the course, 2] incident reporting cards filled out by course participants during the course, and 3] residents' reporting data gathered from hospital incident reporting systems.</p> <p>Results</p> <p>Forty-four residents attended the course and 32 were external controls. Positive changes in knowledge, skills and attitudes were found after the course. Residents' intentions to report incidents were positive at all measurements. Participants filled out 165 incident reporting cards, demonstrating the skills to notice incidents. Residents who had reported incidents before, reported more incidents after the course. However, the number of residents reporting incidents did not increase. An increase in reported incidents was registered by the reporting system of the intervention hospital.</p> <p>Conclusions</p> <p>Patient safety education can have immediate and long-term positive effects on knowledge, skills and attitudes, and modestly influence the reporting behavior of residents.</p

    Discussing Uncertainty and Risk in Primary Care: Recommendations of a Multi-Disciplinary Panel Regarding Communication Around Prostate Cancer Screening

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    BACKGROUND: Shared decision making improves value-concordant decision-making around prostate cancer screening (PrCS). Yet, PrCS discussions remain complex, challenging and often emotional for physicians and average-risk men. OBJECTIVE: In July 2011, the Centers for Disease Control and Prevention convened a multidisciplinary expert panel to identify priorities for funding agencies and development groups to promote evidence-based, value-concordant decisions between men at average risk for prostate cancer and their physicians. DESIGN: Two-day multidisciplinary expert panel in Atlanta, Georgia, with structured discussions and formal consensus processes. PARTICIPANTS: Sixteen panelists represented diverse specialties (primary care, medical oncology, urology), disciplines (sociology, communication, medical education, clinical epidemiology) and market sectors (patient advocacy groups, Federal funding agencies, guideline-development organizations). MAIN MEASURES: Panelists used guiding interactional and evaluation models to identify and rate strategies that might improve PrCS discussions and decisions for physicians, patients and health systems/society. Efficacy was defined as the likelihood of each strategy to impact outcomes. Effort was defined as the relative amount of effort to develop, implement and sustain the strategy. Each strategy was rated (1–7 scale; 7 = maximum) using group process software (ThinkTank(TM)). For each group, intervention strategies were grouped as financial/regulatory, educational, communication or attitudinal levers. For each strategy, barriers were identified. KEY RESULTS: Highly ranked strategies to improve value-concordant shared decision-making (SDM) included: changing outpatient clinic visit reimbursement to reward SDM; development of evidence-based, technology-assisted, point-of-service tools for physicians and patients; reframing confusing prostate cancer screening messages; providing pre-visit decision support interventions; utilizing electronic health records to promote benchmarking/best practices; providing additional training for physicians around value-concordant decision-making; and using re-accreditation to promote training. CONCLUSIONS: Conference outcomes present an expert consensus of strategies likely to improve value-concordant prostate cancer screening decisions. In addition, the methodology used to obtain agreement provides a model of successful collaboration around this and future controversial cancer screening issues, which may be of interest to funding agencies, educators and policy makers. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11606-013-2419-z) contains supplementary material, which is available to authorized users
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