1,312 research outputs found

    Dependence on Dectin-1 Varies With Multiple Candida Species

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    This is the final version. Available from Frontiers Media via the DOI in this recordFour Candida spp. (albicans, glabrata, tropicalis, parapsilosis) cause >95% of invasive Candida infections. C. albicans elicits immune responses via pathogen recognition receptors including C-type lectin-like receptors (CLRs). The CLR, Dectin-1 is important for host immunity to C. albicans and C. glabrata, however, whether Dectin-1 is important for host defense against C. tropicalis or C. parapsilosis is unknown. Therefore, we compared the involvement of Dectin-1 in response to these four diverse Candida spp. We found that Dectin-1 mediates innate cytokine responses to these Candida spp. in a species- and cell-dependent manner. Dectin-1 KO mice succumbed to infection with highly virulent C. albicans while they mostly survived infection with less virulent Candida spp. However, Dectin-1 KO mice displayed increased fungal burden following infection with each Candida spp. Additionally, T cells from Dectin-1 KO mice displayed enhanced effector functions likely due to the inability of Dectin-1 KO mice to clear the infections. Together, these data indicate that Dectin-1 is important for host defense to multiple Candida spp., although the specific roles for Dectin-1 varies with different Candida spp.Wellcome TrustRoyal SocietyUK Dementia Research InstituteMRC Centre for Medical Mycolog

    A stated preference model to value reductions in community severance

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    This paper presents the results of a stated preference survey to assess the value of reductions in community severance (the “barrier effect” of transport infrastructure on the mobility of pedestrians). In a first exercise, participants chose between crossing a road in a place without designated facilities or walking additional minutes to a place where the road is covered over. Half of the participants never chose to cross, regardless of the road design, traffic characteristics, and length of the detour. On average, the other half would only cross the road, if the detour was at least 7.5 minutes, or higher, if the road had extra traffic lanes, no central reservation, and high traffic density. In a second exercise, participants were asked if they would cross the road if they could save money by using a shop or a bus stop on the other side of the road, instead of one on their side of the road. 38% never chose to cross. The cost saving for which the other 62% would cross depends on the scenario, especially regarding traffic volume. On average, participants would only cross a road with high traffic volume if the saving was £2.8. Overall, the study suggests that many people are not willing to trade-off pedestrian safety with shorter walking times or cost savings. People who are willing to trade-off attach greater importance to some aspects (like traffic density) than others (like traffic speed)

    Factors associated with compliance and non-compliance by physicians in a large-scale randomized clinical trial

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    BACKGROUND: In order to minimize the amount of incomplete follow-up data, reducing the non-compliance of participating physicians is one of the key issues for the data coordinating center in a multi-center trial. Identifying the physicians' non-compliance in advance is considered to be an important strategy for more efficient conduct of trials. In this study, we identified physicians' characteristics and factors associated with the need for individual visits to institutions to collect data or to complete information during two years of follow-up in a large Japanese investigator-initiated trial related to cardiovascular disease. METHODS: We categorized the physicians into two groups, "complier" and "non-complier". Odds ratios and corresponding 95% confidence intervals were calculated for 11 factors related to the characteristics of and compliance by physicians. Multiple logistic regression analysis was also performed. In addition, we evaluated the incremental cost for obtaining additional information of the non-compliant physicians. RESULTS: Three factors were identified in multiple logistic regression analysis as being significantly associated with compliance status: 1) prior participation in clinical trials (OR = 0.40 95%CI = 0.21–0.74); 2) physician opinion that the support system for case registration and follow-up was well organized (OR = 0.41 95%CI = 0.22–0.75); and 3) number of patients recruited (OR = 2.25 95%CI = 1.01–5.02). The actual incremental cost was about US 112,000(14.4112,000 (14.4% of total routine follow-up costs) for the non-compliant physicians during the 2 years, or about US 570 per patient. CONCLUSION: Investigator-initiated clinical trials have recently attracted great interest, but they often suffer from insufficient funding. If trial networks are to be well organized, it is important that trials are conducted more efficiently. We believe that our findings will be useful for reducing the additional burden associated with incomplete follow-up data and data lost to follow-up when planning future trials

    Inconsistent strategies to spin up models in CMIP5: Implications for ocean biogeochemical model performance assessment

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    This is the final version of the article. Available from EGU via the DOI in this record.During the fifth phase of the Coupled Model Intercomparison Project (CMIP5) substantial efforts were made to systematically assess the skill of Earth system models. One goal was to check how realistically representative marine biogeochemical tracer distributions could be reproduced by models. In routine assessments model historical hindcasts were compared with available modern biogeochemical observations. However, these assessments considered neither how close modeled biogeochemical reservoirs were to equilibrium nor the sensitivity of model performance to initial conditions or to the spin-up protocols. Here, we explore how the large diversity in spin-up protocols used for marine biogeochemistry in CMIP5 Earth system models (ESMs) contributes to model-to-model differences in the simulated fields. We take advantage of a 500-year spin-up simulation of IPSL-CM5A-LR to quantify the influence of the spin-up protocol on model ability to reproduce relevant data fields. Amplification of biases in selected biogeochemical fields (O2, NO3, Alk-DIC) is assessed as a function of spin-up duration. We demonstrate that a relationship between spin-up duration and assessment metrics emerges from our model results and holds when confronted with a larger ensemble of CMIP5 models. This shows that drift has implications for performance assessment in addition to possibly aliasing estimates of climate change impact. Our study suggests that differences in spin-up protocols could explain a substantial part of model disparities, constituting a source of model-to-model uncertainty. This requires more attention in future model intercomparison exercises in order to provide quantitatively more correct ESM results on marine biogeochemistry and carbon cycle feedbacks.We sincerely thank I. Kriest, F. Joos, the anonymous reviewer and A. Yool for their useful comments on this paper. This work was supported by H2020 project CRESCENDO “Coordinated Research in Earth Systems and Climate: Experiments, kNowledge, Dissemination and Outreach”, which received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement no. 641816 and by the EU FP7 project CARBOCHANGE “Changes in carbon uptake and emissions by oceans in a changing climate” which received funding from the European community’s Seventh Framework Programme under grant agreement no. 264879. Supercomputing time was provided by GENCI (Grand Equipement National de Calcul Intensif) at CCRT (Centre de Calcul Recherche et Technologie), allocation 016178. Finally, we are grateful to the ESGF project which makes data available for all the community. Roland Séférian is grateful to Aurélien Ribes for his kind advices on statistics. Jerry Tjiputra acknowledges ORGANIC project (239965/F20) funded by the Research Council of Norway. Christoph Heinze and Jerry Tjiputra are grateful for support through project EVA – Earth system modelling of climate variations in the Anthropocene (229771/E10) funded by the Research Council of Norway, as well as CPU-time and mass storage provided through NOTUR project NN2345K as well as NorStore project NS2345K. Keith Lindsay and Scott C. Doney acknowledge support from the National Science Foundation

    Extensive dissolution of live pteropods in the Southern Ocean

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    The carbonate chemistry of the surface ocean is rapidly changing with ocean acidification, a result of human activities. In the upper layers of the Southern Ocean, aragonite—a metastable form of calcium carbonate with rapid dissolution kinetics—may become undersaturated by 2050 (ref. 2). Aragonite undersaturation is likely to affect aragonite-shelled organisms, which can dominate surface water communities in polar regions. Here we present analyses of specimens of the pteropod Limacina helicina antarctica that were extracted live from the Southern Ocean early in 2008. We sampled from the top 200m of the water column, where aragonite saturation levels were around 1, as upwelled deep water is mixed with surface water containing anthropogenic CO2. Comparing the shell structure with samples from aragonite-supersaturated regions elsewhere under a scanning electron microscope, we found severe levels of shell dissolution in the undersaturated region alone. According to laboratory incubations of intact samples with a range of aragonite saturation levels, eight days of incubation in aragonite saturation levels of 0.94– 1.12 produces equivalent levels of dissolution. As deep-water upwelling and CO2 absorption by surface waters is likely to increase as a result of human activities2,4, we conclude that upper ocean regions where aragonite-shelled organisms are affected by dissolution are likely to expand

    Differential susceptibility of Dectin-1 isoforms to functional inactivation by neutrophil and fungal proteases.

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    Patients with cystic fibrosis (CF) experience chronic or recurrent bacterial and fungal lung infections. Many patients with CF cannot effectively clear Aspergillus from their lungs. This may result in IgE sensitization and the development of allergic bronchopulmonary aspergillosis, or invasive infections, such as Aspergillus bronchitis. Lung disease in patients with CF is associated with neutrophil-dominated inflammation and elevated levels of the serine protease, neutrophil elastase (NE). Various C-type lectin-like receptors (CLRs), including Dectin-1 and Dectin-2, are involved in the immune response to Aspergillus. Here, we show that purified NE cleaves Dectin-1 in an isoform-specific manner. Bronchoalveolar lavage fluid from patients with CF, which contains high NE activity, induces Dectin-1 cleavage. Similarly, filtrate from a protease-producing strain of Aspergillus fumigatus induces isoform-specific cleavage of Dectin-1. Dectin-1 knockout (KO) cells and NE-treated cells demonstrated reduced phagocytosis of zymosan, a fungal cell wall preparation. In addition, NE cleaves 2 other CLRs, Dectin-2 and Mincle, and fungal-induced cytokine production was reduced in Dectin-1 KO cells, Dectin-2 KO cells, and NE-treated cells. Thus, Dectin-1 and Dectin-2 cleavage by NE and/or A. fumigatus–derived proteases results in an aberrant antifungal immune response that likely contributes to disease pathology in patients with C

    Dissolution dominating calcification process in polar pteropods close to the point of aragonite undersaturation

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    Thecosome pteropods are abundant upper-ocean zooplankton that build aragonite shells. Ocean acidification results in the lowering of aragonite saturation levels in the surface layers, and several incubation studies have shown that rates of calcification in these organisms decrease as a result. This study provides a weight-specific net calcification rate function for thecosome pteropods that includes both rates of dissolution and calcification over a range of plausible future aragonite saturation states (Omega_Ar). We measured gross dissolution in the pteropod Limacina helicina antarctica in the Scotia Sea (Southern Ocean) by incubating living specimens across a range of aragonite saturation states for a maximum of 14 days. Specimens started dissolving almost immediately upon exposure to undersaturated conditions (Omega_Ar,0.8), losing 1.4% of shell mass per day. The observed rate of gross dissolution was different from that predicted by rate law kinetics of aragonite dissolution, in being higher at Var levels slightly above 1 and lower at Omega_Ar levels of between 1 and 0.8. This indicates that shell mass is affected by even transitional levels of saturation, but there is, nevertheless, some partial means of protection for shells when in undersaturated conditions. A function for gross dissolution against Var derived from the present observations was compared to a function for gross calcification derived by a different study, and showed that dissolution became the dominating process even at Omega_Ar levels close to 1, with net shell growth ceasing at an Omega_Ar of 1.03. Gross dissolution increasingly dominated net change in shell mass as saturation levels decreased below 1. As well as influencing their viability, such dissolution of pteropod shells in the surface layers will result in slower sinking velocities and decreased carbon and carbonate fluxes to the deep ocean

    JNK2 Promotes Endothelial Cell Alignment under Flow

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    Endothelial cells in straight, unbranched segments of arteries elongate and align in the direction of flow, a feature which is highly correlated with reduced atherosclerosis in these regions. The mitogen-activated protein kinase c-Jun N-terminal kinase (JNK) is activated by flow and is linked to inflammatory gene expression and apoptosis. We previously showed that JNK activation by flow is mediated by integrins and is observed in cells plated on fibronectin but not on collagen or basement membrane proteins. We now show thatJNK2 activation in response to laminar shear stress is biphasic, with an early peak and a later peak. Activated JNK localizes to focal adhesions at the ends of actin stress fibers, correlates with integrin activation and requires integrin binding to the extracellular matrix. Reducing JNK2 activation by siRNA inhibits alignment in response to shear stress. Cells on collagen, where JNK activity is low, align slowly. These data show that an inflammatory pathway facilitates adaptation to laminar flow, thereby revealing an unexpected connection between adaptation and inflammatory pathways

    Recommendations for a core outcome set for measuring standing balance in adult populations: a consensus-based approach

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    Standing balance is imperative for mobility and avoiding falls. Use of an excessive number of standing balance measures has limited the synthesis of balance intervention data and hampered consistent clinical practice.To develop recommendations for a core outcome set (COS) of standing balance measures for research and practice among adults.A combination of scoping reviews, literature appraisal, anonymous voting and face-to-face meetings with fourteen invited experts from a range of disciplines with international recognition in balance measurement and falls prevention. Consensus was sought over three rounds using pre-established criteria.The scoping review identified 56 existing standing balance measures validated in adult populations with evidence of use in the past five years, and these were considered for inclusion in the COS.Fifteen measures were excluded after the first round of scoring and a further 36 after round two. Five measures were considered in round three. Two measures reached consensus for recommendation, and the expert panel recommended that at a minimum, either the Berg Balance Scale or Mini Balance Evaluation Systems Test be used when measuring standing balance in adult populations.Inclusion of two measures in the COS may increase the feasibility of potential uptake, but poses challenges for data synthesis. Adoption of the standing balance COS does not constitute a comprehensive balance assessment for any population, and users should include additional validated measures as appropriate.The absence of a gold standard for measuring standing balance has contributed to the proliferation of outcome measures. These recommendations represent an important first step towards greater standardization in the assessment and measurement of this critical skill and will inform clinical research and practice internationally

    Risk analysis and outcome of mediastinal wound and deep mediastinal wound infections with specific emphasis to omental transposition

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    <p>Abstract</p> <p>Background</p> <p>To report our experience, with Deep mediastinal wound infections (DMWI). Emphasis was given to the management of deep infections with omental flaps</p> <p>Methods</p> <p>From February 2000 to October 2007, out of 3896 cardiac surgery patients (prospective data collection) 120 pts (3.02%) developed sternal wound infections. There were 104 males & 16 females; (73.7%) CABG, (13.5%) Valves & (9.32%) CABG and Valve.</p> <p>Results</p> <p>Superficial sternal wound infection detected in 68 patients (1.75%) and fifty-two patients (1.34%) developed DMWI. The incremental risk factors for development of DMWI were: Diabetes (OR = 3.62, CI = 1.2-10.98), Pre Op Creatinine > 200 μmol/l (OR = 3.33, CI = 1.14-9.7) and Prolong ventilation (OR = 4.16, CI = 1.73-9.98). Overall mortality for the DMWI was 9.3% and the specific mortality of the omental flap group was 8.3%. 19% of the "DMWI group", developed complications: hematoma 6%, partial flap loss 3.0%, wound dehiscence 5.3%. Mean Hospital Stay: 59 ± 21.5 days.</p> <p>Conclusion</p> <p>Post cardiac surgery sternal wound complications remain challenging. The role of multidisciplinary approach is fundamental, as is the importance of an aggressive early wound exploration especially for deep sternal infections.</p
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