32 research outputs found
XCR1 expression distinguishes human conventional dendritic cell type 1 with full effector functions from their immediate precursors
Dendritic cells (DCs) are major regulators of innate and adaptive immune responses. DCs can be classified into plasmacytoid DCs and conventional DCs (cDCs) type 1 and 2. Murine and human cDC1 share the mRNA expression of XCR1. Murine studies indicated a specific role of the XCR1-XCL1 axis in the induction of immune responses. Here, we describe that human cDC1 can be distinguished into XCR1 and XCR1 cDC1 in lymphoid as well as nonlymphoid tissues. Steady-state XCR1 cDC1 display a preactivated phenotype compared to XCR1 cDC1. Upon stimulation, XCR1 cDC1, but not XCR1 cDC1, secreted high levels of inflammatory cytokines as well as chemokines. This was associated with enhanced activation of NK cells mediated by XCR1 cDC1. Moreover, XCR1 cDC1 excelled in inhibiting replication of Influenza A virus. Further, under DC differentiation conditions, XCR1 cDC1 developed into XCR1 cDC1. After acquisition of XCR1 expression, XCR1 cDC1 secreted comparable level of inflammatory cytokines. Thus, XCR1 is a marker of terminally differentiated cDC1 that licenses the antiviral effector functions of human cDC1, while XCR1 cDC1 seem to represent a late immediate precursor of cDC1
Climate change considerations are fundamental to management of deepâsea resource extraction
Climate change manifestation in the ocean, through warming, oxygen loss, increasing acidification, and changing particulate organic carbon flux (one metric of altered food supply), is projected to affect most deepâocean ecosystems concomitantly with increasing direct human disturbance. Climate drivers will alter deepâsea biodiversity and associated ecosystem services, and may interact with disturbance from resource extraction activities or even climate geoengineering. We suggest that to ensure the effective management of increasing use of the deep ocean (e.g., for bottom fishing, oil and gas extraction, and deepâseabed mining), environmental management and developing regulations must consider climate change. Strategic planning, impact assessment and monitoring, spatial management, application of the precautionary approach, and fullâcost accounting of extraction activities should embrace climate consciousness. Coupled climate and biological modeling approaches applied in the water and on the seafloor can help accomplish this goal. For example, EarthâSystem Model projections of climateâchange parameters at the seafloor reveal heterogeneity in projected climate hazard and time of emergence (beyond natural variability) in regions targeted for deepâseabed mining. Models that combine climateâinduced changes in ocean circulation with particle tracking predict altered transport of early life stages (larvae) under climate change. Habitat suitability models can help assess the consequences of altered larval dispersal, predict climate refugia, and identify vulnerable regions for multiple species under climate change. Engaging the deep observing community can support the necessary data provisioning to mainstream climate into the development of environmental management plans. To illustrate this approach, we focus on deepâseabed mining and the International Seabed Authority, whose mandates include regulation of all mineralârelated activities in international waters and protecting the marine environment from the harmful effects of mining. However, achieving deepâocean sustainability under the UN Sustainable Development Goals will require integration of climate consideration across all policy sectors.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium,
provided the original work is properly cited.
© 2020 The Authors. Global Change Biology published by John Wiley & Sons Lt
A framework for the development of a global standardised marine taxon reference image database (SMarTaR-ID) to support image-based analyses
Video and image data are regularly used in the field of benthic ecology to document biodiversity. However, their use is subject to a number of challenges, principally the identification of taxa within the images without associated physical specimens. The challenge of applying traditional taxonomic keys to the identification of fauna from images has led to the development of personal, group, or institution level reference image catalogues of operational taxonomic units (OTUs) or morphospecies. Lack of standardisation among these reference catalogues has led to problems with observer bias and the inability to combine datasets across studies. In addition, lack of a common reference standard is stifling efforts in the application of artificial intelligence to taxon identification. Using the North Atlantic deep sea as a case study, we propose a database structure to facilitate standardisation of morphospecies image catalogues between research groups and support future use in multiple front-end applications. We also propose a framework for coordination of international efforts to develop reference guides for the identification of marine species from images. The proposed structure maps to the Darwin Core standard to allow integration with existing databases. We suggest a management framework where high-level taxonomic groups are curated by a regional team, consisting of both end users and taxonomic experts. We identify a mechanism by which overall quality of data within a common reference guide could be raised over the next decade. Finally, we discuss the role of a common reference standard in advancing marine ecology and supporting sustainable use of this ecosystem
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Fibrosis Progression Rate in Biopsy-Proven Nonalcoholic Fatty Liver Disease Among People With Diabetes Versus People Without Diabetes: A Multicenter Study
Background & aimsThere are limited data regarding fibrosis progression in biopsy-proven nonalcoholic fatty liver disease (NAFLD) in people with type 2 diabetes mellitus (T2DM) compared with people without T2DM. We assessed the time to fibrosis progression in people with T2DM compared with people without T2DM in a large, multicenter, study of people with NAFLD who had paired liver biopsies.MethodsThis study included 447 adult participants (64% were female) with NAFLD who had paired liver biopsies more than 1 year apart. Liver histology was systematically assessed by a central pathology committee blinded to clinical data. The primary outcome was the cumulative incidence of a â„1-stage increase in fibrosis in participants with T2DM compared with participants without T2DM.ResultsThe mean (SD) age and body mass index (calculated as weight in kilograms divided by the square of the height in meters) were 50.9 (11.5) years and 34.7 (6.3), respectively. The median time between biopsies was 3.3 years (interquartile range, 1.8-6.1 years). Participants with T2DM had a significantly higher cumulative incidence of fibrosis progression at 4 years (24% vs 20%), 8 years (60% vs 50%), and 12 years (93% vs 76%) (P = .005). Using a multivariable Cox proportional hazards model adjusted for multiple confounders, T2DM remained an independent predictor of fibrosis progression (adjusted hazard ratio, 1.69; 95% CI, 1.17-2.43; P = .005). The cumulative incidence of fibrosis regression by â„1 stage was similar in participants with T2DM compared with participants without T2DM (P = .24).ConclusionsIn this large, multicenter cohort study of well-characterized participants with NAFLD and paired liver biopsies, we found that fibrosis progressed faster in participants with T2DM compared with participants without T2DM. These data have important implications for clinical practice and trial design
Increased hepatotoxicity among HIV-infected adults co-infected with <i>Schistosoma mansoni</i> in Tanzania: A cross-sectional study
<div><p>Introduction</p><p>Little is known about hepatotoxicity in patients with schistosome and HIV co-infections. Several studies have reported increased liver enzymes and bilirubin levels associated with schistosome infection. We investigated whether HIV-infected adults on antiretroviral therapy who had <i>S</i>. <i>mansoni</i> co-infection had a higher prevalence of hepatotoxicity than those without.</p><p>Methodology/Principal findings</p><p>We determined the presence and grade of hepatotoxicity among 305 HIV-infected outpatients who had been on medium-term (3â6 months) and long-term (>36 months) antiretroviral therapy in a region of northwest Tanzania where <i>S</i>. <i>mansoni</i> is hyperendemic. We used the AIDS Clinical Trial Group definition to define mild to moderate hepatotoxicity as alanine aminotransferase, alanine aminotransferase, and/or bilirubin elevations of grade 1 or 2, and severe hepatotoxicity as any elevation of grade 3 or 4. We determined schistosome infection status using the serum circulating cathodic antigen rapid test and used logistic regression to determine factors associated with hepatotoxicity. The prevalence of mild-moderate and severe hepatotoxicity was 29.6% (45/152) and 2.0% (3/152) in patients on medium-term antiretroviral therapy and 19.6% (30/153) and 3.3% (5/153) in the patients on long-term antiretroviral therapy. <i>S</i>. <i>mansoni</i> infection was significantly associated with hepatotoxicity on univariable analysis and after controlling for other factors associated with hepatotoxicity including hepatitis B or C and anti-tuberculosis medication use (adjusted odds ratio = 3.0 [1.6â5.8], p = 0.001).</p><p>Conclusions/Significance</p><p>Our work demonstrates a strong association between <i>S</i>. <i>mansoni</i> infection and hepatotoxicity among HIV-infected patients on antiretroviral therapy. Our study highlights the importance of schistosome screening and treatment for patients starting antiretroviral therapy in schistosome-endemic settings. Additional studies to determine the effects of schistosome-HIV co-infections are warranted.</p></div
Factors associated with hepatotoxicity in patients on ART in Tanzania.
<p>Factors associated with hepatotoxicity in patients on ART in Tanzania.</p
Baseline characteristics of 305 HIV-infected, Tanzanian adults on antiretroviral therapy (ART) at Bugando Medical Centre and comparison between patients on ART 3â6 months (GROUP 1) or >36 months (GROUP 2).
<p>Baseline characteristics of 305 HIV-infected, Tanzanian adults on antiretroviral therapy (ART) at Bugando Medical Centre and comparison between patients on ART 3â6 months (GROUP 1) or >36 months (GROUP 2).</p