50 research outputs found

    A novel cardiovascular magnetic resonance risk score for predicting mortality following surgical aortic valve replacement

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    The increasing prevalence of patients with aortic stenosis worldwide highlights a clinical need for improved and accurate prediction of clinical outcomes following surgery. We investigated patient demographic and cardiovascular magnetic resonance (CMR) characteristics to formulate a dedicated risk score estimating long-term survival following surgery. We recruited consecutive patients undergoing CMR with gadolinium administration prior to surgical aortic valve replacement from 2003 to 2016 in two UK centres. The outcome was overall mortality. A total of 250 patients were included (68 ± 12 years, male 185 (60%), with pre-operative mean aortic valve area 0.93 ± 0.32cm2, LVEF 62 ± 17%) and followed for 6.0 ± 3.3 years. Sixty-one deaths occurred, with 10-year mortality of 23.6%. Multivariable analysis showed that increasing age (HR 1.04, P = 0.005), use of antiplatelet therapy (HR 0.54, P = 0.027), presence of infarction or midwall late gadolinium enhancement (HR 1.52 and HR 2.14 respectively, combined P = 0.12), higher indexed left ventricular stroke volume (HR 0.98, P = 0.043) and higher left atrial ejection fraction (HR 0.98, P = 0.083) associated with mortality and developed a risk score with good discrimination. This is the first dedicated risk prediction score for patients with aortic stenosis undergoing surgical aortic valve replacement providing an individualised estimate for overall mortality. This model can help clinicians individualising medical and surgical care. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00930735 and ClinicalTrials.gov Identifier: NCT01755936

    Interleukin-17A Mediates Acquired Immunity to Pneumococcal Colonization

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    Although anticapsular antibodies confer serotype-specific immunity to pneumococci, children increase their ability to clear colonization before these antibodies appear, suggesting involvement of other mechanisms. We previously reported that intranasal immunization of mice with pneumococci confers CD4+ T cell–dependent, antibody- and serotype-independent protection against colonization. Here we show that this immunity, rather than preventing initiation of carriage, accelerates clearance over several days, accompanied by neutrophilic infiltration of the nasopharyngeal mucosa. Adoptive transfer of immune CD4+ T cells was sufficient to confer immunity to naïve RAG1−/− mice. A critical role of interleukin (IL)-17A was demonstrated: mice lacking interferon-γ or IL-4 were protected, but not mice lacking IL-17A receptor or mice with neutrophil depletion. In vitro expression of IL-17A in response to pneumococci was assayed: lymphoid tissue from vaccinated mice expressed significantly more IL-17A than controls, and IL-17A expression from peripheral blood samples from immunized mice predicted protection in vivo. IL-17A was elicited by pneumococcal stimulation of tonsillar cells of children or adult blood but not cord blood. IL-17A increased pneumococcal killing by human neutrophils both in the absence and in the presence of antibodies and complement. We conclude that IL-17A mediates pneumococcal immunity in mice and probably in humans; its elicitation in vitro could help in the development of candidate pneumococcal vaccines

    Protective Contributions against Invasive Streptococcus pneumoniae Pneumonia of Antibody and Th17-Cell Responses to Nasopharyngeal Colonisation

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    The nasopharyngeal commensal bacteria Streptococcus pneumoniae is also a frequent cause of serious infections. Nasopharyngeal colonisation with S. pneumoniae inhibits subsequent re-colonisation by inducing Th17-cell adaptive responses, whereas vaccination prevents invasive infections by inducing antibodies to S. pneumoniae capsular polysaccharides. In contrast, protection against invasive infection after nasopharyngeal colonisation with mutant S. pneumoniae strains was associated with antibody responses to protein antigens. The role of colonisation-induced Th17-cell responses during subsequent invasive infections is unknown. Using mouse models, we show that previous colonisation with S. pneumoniae protects against subsequent lethal pneumonia mainly by preventing bacteraemia with a more modest effect on local control of infection within the lung. Previous colonisation resulted in CD4-dependent increased levels of Th17-cell cytokines during subsequent infectious challenge. However, mice depleted of CD4 cells prior to challenge remained protected against bacteraemia, whereas no protection was seen in antibody deficient mice and similar protection could be achieved through passive transfer of serum. Serum from colonised mice but not antibody deficient mice promoted phagocytosis of S. pneumoniae, and previously colonised mice were able to rapidly clear S. pneumoniae from the blood after intravenous inoculation. Thus, despite priming for a Th17-cell response during subsequent infection, the protective effects of prior colonisation in this model was not dependent on CD4 cells but on rapid clearance of bacteria from the blood by antibody-mediated phagocytosis. These data suggest that whilst nasopharyngeal colonisation induces a range of immune responses, the effective protective responses depend upon the site of subsequent infectio

    Measuring the outcomes of long-term care for unpaid carers: Comparing the ASCOT-Carer, Carer Experience Scale and EQ-5D-3L

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    Background: The ASCOT-Carer and Carer Experience Scale are instruments designed to capture aspects of quality of life ‘beyond health’ for family carers. The aim of this study was to compare and validate these two carer care-related measures, with a secondary aim to compare both instruments to the three-level EQ-5D (EQ-5D-3L) measure of health-related quality of life. Methods: An interview survey was conducted with 387 carers of adults who used long-term care (also known as social care) support in England. Construct validity by hypothesis testing was assessed using Pearson correlation coefficient. Exploratory factor analysis was also applied to investigate the dimensionality of the combined items from the ASCOT-Carer and CES (as measures of carer quality of life ‘beyond health’) and the EQ-5D (as a measure of health-related quality of life). Results: In the construct validity analysis, hypothesised differences in correlations were observed with two exceptions. The exploratory factor analysis indicated that the ASCOT-Carer, CES and EQ-5D-3L items loaded onto three separate factors. The first factor comprised the seven ASCOT-Carer items plus two CES items (activities outside caring, support from friends and family). The second factor comprised three of the six CES items (fulfilment from caring, control over caring and getting on with the person you care for). The third factor included four of the five EQ-5D-3L items. Conclusion: The findings indicate that the ASCOT-Carer, CES and EQ-5D-3L capture separate constructs of social care-related quality of life (ASCOT-Carer) and carer experience (CES), which partially overlap in relation to activities outside caring and social support, and health-related quality of life (EQ-5D-3L). The ASCOT-Carer and CES are both promising measures for the evaluation of social care support for carers that capture aspects of quality of life ‘beyond health’. The choice of whether to use the ASCOT-Carer or CES depends on the study objectives

    The Evolution of Religion: How Cognitive By-Products, Adaptive Learning Heuristics, Ritual Displays, and Group Competition Generate Deep Commitments to Prosocial Religio

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    Understanding religion requires explaining why supernatural beliefs, devotions, and rituals are both universal and variable across cultures, and why religion is so often associated with both large-scale cooperation and enduring group conflict. Emerging lines of research suggest that these oppositions result from the convergence of three processes. First, the interaction of certain reliably developing cognitive processes, such as our ability to infer the presence of intentional agents, favors—as an evolutionary by-product—the spread of certain kinds of counterintuitive concepts. Second, participation in rituals and devotions involving costly displays exploits various aspects of our evolved psychology to deepen people's commitment to both supernatural agents and religious communities. Third, competition among societies and organizations with different faith-based beliefs and practices has increasingly connected religion with both within-group prosociality and between-group enmity. This connection has strengthened dramatically in recent millennia, as part of the evolution of complex societies, and is important to understanding cooperation and conflict in today's world

    A distinct role for B1b lymphocytes in T cell-independent immunity

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    Pathogenesis of infectious disease is not only determined by the virulence of the microbe but also by the immune status of the host. Vaccination is the most effective means to control infectious diseases. A hallmark of the adaptive immune system is the generation of B cell memory, which provides a long-lasting protective antibody response that is central to the concept of vaccination. Recent studies revealed a distinct function for B1b lymphocytes, a minor subset of mature B cells that closely resembles that of memory B cells in a number of aspects. In contrast to the development of conventional B cell memory, which requires the formation of germinal centers and T cells, the development of B1b cell-mediated long-lasting antibody responses occurs independent of T cell help. T cell-independent (TI) antigens are important virulence factors expressed by a number of bacterial pathogens, including those associated with biological threats. TI antigens cannot be processed and presented to T cells and therefore are known to possess restricted T cell-dependent (TD) immunogenicity. Nevertheless, specific recognition of TI antigens by B1b cells and the highly protective antibody responses mounted by them clearly indicate a crucial role for this subset of B cells. Understanding the mechanisms of long-term immunity conferred by B1b cells may lead to improved vaccine efficacy for a variety of TI antigens

    Listeria monocytogenes in Milk Products

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    peer-reviewedMilk and milk products are frequently identified as vectors for transmission of Listeria monocytogenes. Milk can be contaminated at farm level either by indirect external contamination from the farm environment or less frequently by direct contamination of the milk from infection in the animal. Pasteurisation of milk will kill L. monocytogenes, but post-pasteurisation contamination, consumption of unpasteurised milk and manufacture of unpasteurised milk products can lead to milk being the cause of outbreaks of listeriosis. Therefore, there is a concern that L. monocytogenes in milk could lead to a public health risk. To protect against this risk, there is a need for awareness surrounding the issues, hygienic practices to reduce the risk and adequate sampling and analysis to verify that the risk is controlled. This review will highlight the issues surrounding L. monocytogenes in milk and milk products, including possible control measures. It will therefore create awareness about L. monocytogenes, contributing to protection of public health

    Protection from ultraviolet damage and photocarcinogenesis by vitamin d compounds

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    © Springer Nature Switzerland AG 2020. Exposure of skin cells to UV radiation results in DNA damage, which if inadequately repaired, may cause mutations. UV-induced DNA damage and reactive oxygen and nitrogen species also cause local and systemic suppression of the adaptive immune system. Together, these changes underpin the development of skin tumours. The hormone derived from vitamin D, calcitriol (1,25-dihydroxyvitamin D3) and other related compounds, working via the vitamin D receptor and at least in part through endoplasmic reticulum protein 57 (ERp57), reduce cyclobutane pyrimidine dimers and oxidative DNA damage in keratinocytes and other skin cell types after UV. Calcitriol and related compounds enhance DNA repair in keratinocytes, in part through decreased reactive oxygen species, increased p53 expression and/or activation, increased repair proteins and increased energy availability in the cell when calcitriol is present after UV exposure. There is mitochondrial damage in keratinocytes after UV. In the presence of calcitriol, but not vehicle, glycolysis is increased after UV, along with increased energy-conserving autophagy and changes consistent with enhanced mitophagy. Reduced DNA damage and reduced ROS/RNS should help reduce UV-induced immune suppression. Reduced UV immune suppression is observed after topical treatment with calcitriol and related compounds in hairless mice. These protective effects of calcitriol and related compounds presumably contribute to the observed reduction in skin tumour formation in mice after chronic exposure to UV followed by topical post-irradiation treatment with calcitriol and some, though not all, related compounds

    Hospitality Research: A Comparison of Industry Professionals\u27 and Educators\u27 Perceptions

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    The study surveyed 1,200 hospitality industry professionals and compared the results to hospitality educators\u27 to determine their perceived expectations, benefits and use of hospitality research. It analyzed the major areas of research interests each group had and how closely research has served those interests. Results suggested that there are some significant gaps between the industry professionals and the educators. Considerations are suggested for narrowing the gaps

    Private Financing of the Military: A Local Political Economy Approach

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    The article of record as published may be located at http://dx.doi.org/10.1007/s12116-012-9119-2In developing countries that are democratizing after military rule, and undergoing liberalizing economic reforms that encourage a shrinking of the state, what missions are the armed forces performing, who funds those missions, who benefits from military services, and why? This article analyzes security provision by the armed forces for paying clients—especially private companies in extractive industries—in accordance with negotiations between clients and commanders of the local military units that directly provide the security. The analysis identifies two paths toward local military–client relations. First, weak state capacity may mean that government control of military finances brought by democratization and economic reform remains limited to the national level, promoting local military–client exchanges. Second, amid minimal government control of military finances, even in the capital city, demand from companies in the powerful extractive industries and from recently endowed subnational governments can encourage local military–client contracting
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