8 research outputs found

    Investigation of molluscan survivorship across the Cenomanian-Turonian Boundary Event using ecological niche modeling

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    In the beginning of the Late Cretaceous, the Western Interior Seaway experienced the effects of a global ocean anoxic event (OAE2, or the Bonarelli Event) across the Cenomanian-Turonian (C/T) boundary (~94 Ma). This event resulted in major environmental and biological disturbances creating significant biotic turnover, with recent research suggesting near mass extinction levels in some clades. In this study we utilize a paleobiological application of a modern ecological modeling technique (PaleoENM), to test whether changes in species’ survivorship and distribution patterns across this event relate to changes in their predicted suitable habitat area and abiotic niche dimensions. Results suggest that survivorship across the C/T is not strongly correlated with available suitable habitat. Additionally, a quarter of the taxa demonstrate significant abiotic niche stability across the C/T. These findings are consistent irrespective of higher taxonomic groups (i.e., genera), which suggests taxon-specific responses to environmental changes at the macroevolutionary scale of this study. This research supports the importance of biogeography in understanding and predicting species longevity and the maintenance of biodiversity. Application of the general principles described here to modern biological systems perturbed by human-induced anoxia may positively inform conservation efforts and predictions of modern extinction dynamics

    Thymus-specific serine protease contributes to the diversification of the functional endogenous CD4 T cell receptor repertoire

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    Thymus-specific serine protease expression in stromal as well as hematopoietic cells in the thymus is needed for diversification of the endogenous repertoire of TCRs specific for a particular protein antigen

    Genetic and phenotypic intra-species diversity of alga Tisochrysis lutea reveals original genetic structure and domestication potential

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    Oceanic phytoplankton species are generally composed of many strains, with intra-species diversity consisting of genetic and phenotypic variability. Despite its importance in ecological and biotechnological contexts, this intra-species diversity and variation among strains has been little studied. We investigated the intra-species diversity of the microalga Tisochrysis lutea, a haptophyte of the Isochrysidales order. Inter-strain diversity of T. lutea was studied because of the economic importance of the species as a feed in aquaculture and for antioxidant metabolite production, particularly fucoxanthin and other carotenoids, which have health benefits. We analysed Tara Ocean datasets which revealed that T. lutea was present in the Pacific, Atlantic and Indian Oceans but not in the Arctic or Austral Oceans. We next made phenotypic and genotypic comparisons of 11 strains of T. lutea from worldwide algal collections. All strains were cultivated in the same controlled conditions for one week, and several phenotypic traits were measured, notably antioxidant content. In parallel, the genomes of each strain were sequenced, and genetic variants identified. At the genetic and phenotypic levels, the strains were distinct from each other and our analysis revealed natural trait variations of interest in relation to further exploitation in domestication programmes. A large number of genetic variations were identified among the strains, but no major differences in genome size were observed. Moreover, limited genetic structure was observed among these strains, which could be a consequence of the complex life history of species within the Isochrysidales. Our study provides new knowledge on the intra-species diversity that should be considered in future environmental studies and breeding programmes. Highlights Tisochrysis lutea is found in many parts of the world’s oceans. T. lutea has high inter-strain phenotypic and genomic variation. Genetic structure of strains from culture collections is limited

    Differences in Disability Perception in Systemic Sclerosis: A Mirror Survey of Patients and Health Care Providers

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    Differences in disability perception between patients and care providers may impact outcomes. We aimed to explore differences in disability perception between patients and care providers in systemic sclerosis (SSc). We conducted a cross-sectional internet-based mirror survey. SSc patients participating in the online SPIN Cohort and care providers affiliated with 15 scientific societies were surveyed using the Cochin Scleroderma International Classification of Functioning, Disability and Health (ICF)-65 questionnaire, including 65 items (from 0 to 10), representing 9 domains of disability. Mean differences between patients and care providers were calculated. Care providers’ characteristics associated with a mean difference ≥ 2 of 10 points were assessed in multivariate analysis. Answers were analyzed for 109 patients and 105 care providers. The mean age of patients was 55.9 (14.7) years and the disease duration was 10.1 (7.5) years. For all domains of the ICF-65, care providers’ rates were higher than those of patients. The mean difference was 2.4 (1.0) of 10 points. Care providers’ characteristics associated with this difference were organ-based specialty (OR = 7.0 [2.3–21.2]), younger age (OR = 2.7 [1.0–7.1]) and following patients with disease duration ≥5 years (OR = 3.0 [1.1–8.7]). We found systematic differences in disability perception between patients and care providers in SSc

    Differences in Disability Perception in Systemic Sclerosis: A Mirror Survey of Patients and Health Care Providers

    No full text
    Differences in disability perception between patients and care providers may impact outcomes. We aimed to explore differences in disability perception between patients and care providers in systemic sclerosis (SSc). We conducted a cross-sectional internet-based mirror survey. SSc patients participating in the online SPIN Cohort and care providers affiliated with 15 scientific societies were surveyed using the Cochin Scleroderma International Classification of Functioning, Disability and Health (ICF)-65 questionnaire, including 65 items (from 0 to 10), representing 9 domains of disability. Mean differences between patients and care providers were calculated. Care providers’ characteristics associated with a mean difference ≄ 2 of 10 points were assessed in multivariate analysis. Answers were analyzed for 109 patients and 105 care providers. The mean age of patients was 55.9 (14.7) years and the disease duration was 10.1 (7.5) years. For all domains of the ICF-65, care providers’ rates were higher than those of patients. The mean difference was 2.4 (1.0) of 10 points. Care providers’ characteristics associated with this difference were organ-based specialty (OR = 7.0 [2.3–21.2]), younger age (OR = 2.7 [1.0–7.1]) and following patients with disease duration ≄5 years (OR = 3.0 [1.1–8.7]). We found systematic differences in disability perception between patients and care providers in SSc

    RBD- specific Th1 responses are associated with vaccine-induced protection against SARS-CoV-2 infection in patients with hematological malignancies

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    ABSTRACTThe SARS-CoV-2 pandemic still represents a threat for immunosuppressed and hematological malignancy (HM) bearing patients, causing increased morbidity and mortality. Given the low anti-SARSCoV-2 IgG titers post-vaccination, the COVID-19 threat prompted the prophylactic use of engineered anti-SARS-CoV-2 monoclonal antibodies. In addition, potential clinical significance of T cell responses has been overlooked during the first waves of the pandemic, calling for additional in-depth studies. We reported that the polarity and the repertoire of T cell immune responses govern the susceptibility to SARS-CoV-2 infection in health care workers and solid cancer patients. Here, we longitudinally analyzed humoral and cellular immune responses at each BNT162b2 mRNA vaccine injection in 47 HM patients under therapy. Only one-third of HM, mostly multiple myeloma (MM) bearing patients, could mount S1-RBD-specific IgG responses following BNT162b2 mRNA vaccines. This vaccine elicited a S1-RBD-specific Th1 immune response in about 20% patients, mostly in MM and Hodgkin lymphoma, while exacerbating Th2 responses in the 10% cases that presented this recognition pattern at baseline (mostly rituximab-treated patients). Performing a third booster barely improved the percentage of patients developing an S1-RBD-specific Th1 immunity and failed to seroconvert additional HM patients. Finally, 16 patients were infected with SARS-CoV-2, of whom 6 developed a severe infection. Only S1-RBD-specific Th1 responses were associated with protection against SARS-CoV2 infection, while Th2 responses or anti-S1-RBD IgG titers failed to correlate with protection. These findings herald the paramount relevance of vaccine-induced Th1 immune responses in hematological malignancies

    The Polarity and Specificity of Antiviral T Lymphocyte Responses Determine Susceptibility to SARS-CoV-2 Infection in Patients with Cancer and Healthy Individuals

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    International audienceAbstract Vaccination against coronavirus disease 2019 (COVID-19) relies on the in-depth understanding of protective immune responses to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). We characterized the polarity and specificity of memory T cells directed against SARS-CoV-2 viral lysates and peptides to determine correlates with spontaneous, virus-elicited, or vaccine-induced protection against COVID-19 in disease-free and cancer-bearing individuals. A disbalance between type 1 and 2 cytokine release was associated with high susceptibility to COVID-19. Individuals susceptible to infection exhibited a specific deficit in the T helper 1/T cytotoxic 1 (Th1/Tc1) peptide repertoire affecting the receptor binding domain of the spike protein (S1-RBD), a hotspot of viral mutations. Current vaccines triggered Th1/Tc1 responses in only a fraction of all subject categories, more effectively against the original sequence of S1-RBD than that from viral variants. We speculate that the next generation of vaccines should elicit Th1/Tc1 T-cell responses against the S1-RBD domain of emerging viral variants. Significance: This study prospectively analyzed virus-specific T-cell correlates of protection against COVID-19 in healthy and cancer-bearing individuals. A disbalance between Th1/Th2 recall responses conferred susceptibility to COVID-19 in both populations, coinciding with selective defects in Th1 recognition of the receptor binding domain of spike. See related commentary by McGary and Vardhana, p. 892. This article is highlighted in the In This Issue feature, p. 87
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