8,216 research outputs found

    A comparison of sequential total and activated white cell count in patients undergoing coronary artery bypass grafting, using cardiopulmonary bypass, with and without a white cell filter

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    Introduction Cardiopulmonary bypass (CPB) has been shown to induce a systemic inflammatory response similar to the local reaction seen after tissue damage [1]. This leads to the release of toxic substances, such as elastase, which cause endothelial damage and may adversely affect outcome [2]. Use of a leucocyte depleting arterial line filter is one of many anti-inflammatory strategies that are undergoing evaluation. Leucocyte depleting filters may be capable of selectively removing activated white cells [3], but this has not been proved in vivo. The aim of the present study was to compare sequential total and activated white cells during CPB, using either a leucocyte depleting or standard arterial line filter. Materials and methods After local ethical committee approval, 20 patients undergoing coronary artery bypass grafting using CPB were prospectively randomly allocated to have either a Leukogard LG–6 (Pall Biomedical, Portsmouth, UK) or a nonleucocyte depleting filter inserted into the arterial line of the CPB circuit. Arterial limb blood samples were taken immediately after institution of CPB (0min) and at 10–min intervals throughout the bypass period. Activated white cells were identified using nitroblue tetrazolium, then both total and activated white cell numbers counted after staining with Leucoplate.Results Table 1 shows the number of white cells counted/1.25 ? l (volume of a single channel of Nageotte counting chamber) using light microscopy (× 25).Conclusion The LG6 leucocyte filter reduces the total white cell count and is capable of selectively removing activated white cells during CPB. The exact relationship between leucocyte depletion and improved patient outcome still remains unclear

    Water quality at the habitat of the Podostemaceae in Ghana

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    The water quality and river catchment characteristics of Ankasa, Asuboni and Pawnpawn rivers in Ghana where Podostemaceae grow were determined using standard methods. The altitude of the sites ranged from 100 to 290 mabove sea level. The catchment areas for the sites vary from 35 to 171 km2. Between 10–81% of the catchment areas of the sites are within forest reserves. The study showed that the Podostemaceae in Ghana inhabit rivers with the following range of physico-chemical characteristics: pH 6.7–7.3, calcium 2.2–16.0 mg l-1, ammonia-nitrogen 0.07–0. 90 mg l-1, chloride 6.8–38.0 mg l-1, electrical conductivity 26.4–138.0 mS cm-1, magnesium 0.4–9.7 mg l-1, nitrate-nitrogen 0.1–0.6 mg l-1, phosphate 0.01–0.30 mgl-1, silicate 0-21.4 mg l-1 and sulphate 1.5–20.8 mg l-1. The results indicate the quality of water at the habitat of Podostemaceae in Ghana

    The early experiences of Physician Associate students in the UK: A regional cross-sectional study investigating factors associated with engagement

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    Background The number of physician associates (PAs) training and working in the UK has increased over the last few years following the proliferation of postgraduate courses. Understanding early experiences and what impacts on engagement is important if we are to appropriately support this relatively new professional group. Methods This paper reports on a cross-sectional analysis of the first year of data from a prospective 10-year longitudinal cohort study. First year PA students (n = 89) were enrolled from five universities in one UK region where the training programmes were less than 2 years old. Data collected were: demographic information, wellbeing, burnout and engagement, expectations, placement experience, performance and caring responsibilities. Pearson’s correlations were used to examine relationships between variables and to select variables for a hierarchical regression analysis to understand which factors were associated with engagement. Descriptive statistics were calculated for questions relating to experience. Results The experiences of PA students during their first 3–6 months were mixed. For example, 78.7% of students felt that there were staff on placement they could go to for support, however, 44.8% reported that staff did not know about the role and 61.3% reported that staff did not know what clinical work they should undertake. Regression analysis found that their level of engagement was associated with their perceived career satisfaction, overall well-being, and caring responsibilities. Conclusions The support systems required for PAs may need to be examined as results showed that the PA student demographic is different to that of medical students and caring responsibilities are highly associated with engagement. A lack of understanding around the PA role in clinical settings may also need to be addressed in order to better support and develop this workforce

    Reconciling and reconceptualising servitization research: drawing on modularity, platforms, ecosystems, risk and governance to develop mid-range theory

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    PURPOSE: This research bridges disparate research on servitization, namely product–service systems (PSS) and integrated solutions (IS), to provide valuable insights for the progression of the field. It acts as a reconciliation of these research streams and offers a reconceptualised agenda incorporating recent research on platforms, ecosystems, modularity, risk and governance as key conceptual themes to synthesise and build theory. DESIGN/METHODOLOGY/APPROACH: This is a conceptual, theory development article focused on advancing thinking on servitization by identifying systematic and theoretically informed research themes. It also proposes future research opportunities to advance theoretical contributions and practical implications for servitization research. FINDINGS: By reviewing and synthesising extant PSS and IS research, this article identified five core themes – namely modularity, platforms, ecosystems, risks and governance. The importance of these five themes and their linkages to PSS and IS are examined and a theoretical framework with a future research agenda to advance servitization is proposed. ORIGINALITY/VALUE: This paper considers the similarities and differences between PSS and IS in order to develop a theory and to reconcile formerly disparate research efforts by establishing linkages between core themes and identifying valuable synergies for scholars. The importance of the core themes and current gaps within and across these themes are shown, and a mid-range theory for servitization is positioned to bridge the servitization-related PSS and IS communities

    Envelope Determinants of Equine Lentiviral Vaccine Protection

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    Lentiviral envelope (Env) antigenic variation and associated immune evasion present major obstacles to vaccine development. The concept that Env is a critical determinant for vaccine efficacy is well accepted, however defined correlates of protection associated with Env variation have yet to be determined. We reported an attenuated equine infectious anemia virus (EIAV) vaccine study that directly examined the effect of lentiviral Env sequence variation on vaccine efficacy. The study identified a significant, inverse, linear correlation between vaccine efficacy and increasing divergence of the challenge virus Env gp90 protein compared to the vaccine virus gp90. The report demonstrated approximately 100% protection of immunized ponies from disease after challenge by virus with a homologous gp90 (EV0), and roughly 40% protection against challenge by virus (EV13) with a gp90 13% divergent from the vaccine strain. In the current study we examine whether the protection observed when challenging with the EV0 strain could be conferred to animals via chimeric challenge viruses between the EV0 and EV13 strains, allowing for mapping of protection to specific Env sequences. Viruses containing the EV13 proviral backbone and selected domains of the EV0 gp90 were constructed and in vitro and in vivo infectivity examined. Vaccine efficacy studies indicated that homology between the vaccine strain gp90 and the N-terminus of the challenge strain gp90 was capable of inducing immunity that resulted in significantly lower levels of post-challenge virus and significantly delayed the onset of disease. However, a homologous N-terminal region alone inserted in the EV13 backbone could not impart the 100% protection observed with the EV0 strain. Data presented here denote the complicated and potentially contradictory relationship between in vitro virulence and in vivo pathogenicity. The study highlights the importance of structural conformation for immunogens and emphasizes the need for antibody binding, not neutralizing, assays that correlate with vaccine protection. © 2013 Craigo et al

    A life less lonely: the state of the art in interventions to reduce loneliness in people with mental health problems

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    PURPOSE: There is growing evidence of significant harmful effects of loneliness. Relatively little work has focused on how best to reduce loneliness in people with mental health problems. We aim to present an overview of the current state of the art in loneliness interventions in people with mental health problems, identify relevant challenges, and highlight priorities for future research and implementation. METHODS: A scoping review of the published and grey literature was conducted, as well as discussions with relevant experts, to propose a broad classification system for types of interventions targeting loneliness. RESULTS: We categorised interventions as ‘direct’, targeting loneliness and related concepts in social relationships, and ‘indirect’ broader approaches to well-being that may impact on loneliness. We describe four broad groups of direct interventions: changing cognitions; social skills training and psychoeducation; supported socialisation or having a ‘socially-focused supporter’; and ‘wider community approaches’. The most promising emerging evidence appears to be in ‘changing cognitions’, but, as yet, no approaches have a robust evidence base. Challenges include who is best placed to offer the intervention, how to test such complex interventions, and the stigma surrounding loneliness. CONCLUSIONS: Development of clearly defined loneliness interventions, high-quality trials of effectiveness, and identifying which approaches work best for whom is required. Promising future approaches may include wider community initiatives and social prescribing. It is important to place loneliness and social relationships high on the wider public mental health and research agenda

    Genetically based adaptive trait shifts at an expanding mangrove range margin

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    AbstractNeotropical black mangrove (Avicennia germinans) is expanding poleward into temperate salt marsh along Atlantic Florida, USA, with field evidence of trait shifts consistent with greater cold tolerance within range margin populations. However, whether these shifts have a genetic basis remains unanswered. To address this gap, we measured multiple phenotypic traits of twenty A. germinans maternal cohorts from areas in both the Atlantic Florida range core and margin in a 2-year greenhouse common garden with annual temperatures analogous to range margin conditions. Compared to those from the range core, range margin cohorts survived in greater numbers, established (i.e., produced first true leaves) more quickly, and were less stressed under winter temperatures. Range margin cohorts were not taller, but invested more into lateral growth and biomass accumulation that presumably reflects adaptation to their colder and open-canopy environment. Range margin cohorts also exhibited leaf traits consistent with greater resource acquisition that may compensate for a shorter growing season and reduced light quality at higher latitude. Our results suggest that genetically based phenotypic differences better enable these range margin mangroves to thrive within their stressful environment and may facilitate further poleward expansion. An improved understanding of adaptive trait variation within ecologically important mangrove foundation species should also help inform coastal restoration initiatives.</jats:p
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