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Loureiro, S.

Publications and source records attributed to Loureiro, S..

3 recordsLinked to original sources

Herbivore pressure modulates soil multifunctionality in a Mediterranean landscape

Ongoing global environmental changes demand cost-effective strategies to restore ecosystem functioning. Within this context, the reintroduction of large mammalian herbivores has emerged as a promising approach to recover ecological processes and foster self-sustaining, biodiverse ecosystems. However, the impacts of such initiatives remain poorly understood, particularly regarding their effects on soil functions and ecological processes. We tested whether large herbivore densities (wild horses (Garrano breed) and cattle (Maronesa breed, an ancient lineage close to aurochs) modulates soil multifunctionality (the simultaneous provision of multiple ecosystem functions) across habitats (grasslands, shrublands, and forests) and seasons (fall and spring) in a Mediterranean landscape. Using composite multivariate indices describing soil functions related to biogeochemical cycles (i.e., enzymatic activities) and physicochemical properties (pH, conductivity, organic matter, and nutrient loads), we found that soil enzymatic activities varied seasonally, being higher in spring, and interacted with habitat and herbivore pressure gradients. Habitat and herbivore pressure explained the variation in soil multifunctionality during spring, while in fall it was mainly driven by herbivore pressure. Enzymatic stoichiometry, particularly C:P ratios, strongly predicted soil fertility and multifunctionality, showing positive relationships in forest habitats and under herbivore pressure. A mechanistic approach confirmed that herbivore impacts on soil functioning operated primarily through changes in soil properties and nutrient cycling rather than direct effects. Mediterranean landscapes are rapidly changing, and our results highlight herbivore management as a key tool to sustain soil ecological processes under the rewilding framework. Highlights- Large herbivores impacted soil functions and properties in different habitats - Large herbivores significantly impacted soil nutrient cycling and multifunctionality. - The magnitude of the effects was dependent on season and habitat - Large herbivores indirectly impact soil ecosystem multifunctionality through changes in soil properties.

ecology↗

Aberrant glycosylation of anti-SARS-CoV-2 IgG is a pro-thrombotic stimulus for platelets

A subset of patients with COVID-19 become critically ill, suffering from severe respiratory problems and also increased rates of thrombosis. The causes of thrombosis in severely ill COVID-19 patients are still emerging, but the coincidence of critical illness with the timing of the onset of adaptive immunity could implicate an excessive immune response. We hypothesised that platelets might be susceptible to activation by anti-SARS-CoV-2 antibodies and contribute to thrombosis. We found that immune complexes containing recombinant SARS-CoV-2 spike protein and anti-spike IgG enhanced platelet-mediated thrombosis on von Willebrand Factor in vitro, but only when the glycosylation state of the Fc domain was modified to correspond with the aberrant glycosylation previously identified in patients with severe COVID-19. Furthermore, we found that activation was dependent on FcyRIIA and we provide in vitro evidence that this pathogenic platelet activation can be counteracted by therapeutic small molecules R406 (fostamatinib) and ibrutinib that inhibit tyrosine kinases syk and btk respectively or by the P2Y12 antagonist cangrelor.

immunology↗

Recombinant SARS-CoV-2 spike proteins for sero-surveillance and epitope mapping

The newly emergent SARS-CoV-2 coronavirus is closely related to SARS-CoV which emerged in 2002. Studies on coronaviruses in general, and SARS in particular, have identified the virus spike protein (S) as being central to virus tropism, to the generation of a protective antibody response and to the unambiguous detection of past infections. As a result of this centrality SARS-CoV-2 S protein has a role in many aspects of research from vaccines to diagnostic tests. We describe a number of recombinant forms of SARS-CoV-2 S expressed in commonly available expression systems and their preliminary use in diagnostics and epitope mapping. These sources may find use in the current and future analysis of the virus and the Covid-19 disease it causes.

microbiology↗