RCAAP Repository

Aim Habitat diversity has been linked to the diversity and structure of island communities, however, little is known about patterns and processes within habitats. Here we aim to determine the contributions of habitat type and inferred dispersal frequency to the differences in taxonomic structure between assemblages in the same island habitat. Location The Macaronesian archipelagos (Azores, Madeira, the Canary Islands and Cabo Verde). Taxon Spiders (Araneae). Methods We established forest and dry habitat sites (each with five plots) on two islands per archipelago. We collected spiders using standardised sampling protocols. We tested the differences in beta diversity separately for each habitat and for each inferred category of ballooning (an aerial dispersal strategy) frequency across geographic scales through nested non-parametric permutational multivariate analyses of variance. We then tested whether ballooning and habitat influenced heterogeneity in species composition (dispersion in beta diversity) in the two habitat types. We analysed the effects of habitat and ballooning on species abundance distribution (SAD) and rarity by fitting Gambin models and evaluating the contribution of ballooning categories to SAD. Results Communities of the same archipelago and habitat were taxonomically more similar, and beta diversity increased with geographic scale, being greater in dry habitats. There was greater species replacement among assemblages in dry habitats than in forests, with greater differences for rare ballooners. There were no differences in SAD between habitats although dry habitat sites seemed to harbour more species with low abundances (rare species) than forests. Main conclusions Habitat type does not only condition the differences between spider assemblages of the same habitat but also the scale at which they occur. These differences may be determined by the heterogeneity in the physical structure of each habitat as well as how much this structure facilitates aerial dispersal (ballooning), and should be considered in theories/hypotheses on island community assembly as well as in conservation strategies.

The invasive Vespa velutina has been widely referred as an effective predator of honeybees. Despite the potential risk to pollination services provision and honey production, there is no accurate quantification and assessment of its real consequences for honeybees. To date, the identification of the honeybee and other insects in the diet of V. velutina has been investigated by direct observation of adult foraging or examination of food pellets. To overcome these limitations, in this study we used a DNA metabarcoding approach to evaluate the usefulness of different types of sample (jaws and stomachs collected from workers and larval faecal pellets taken from the hornet comb) to investigate the predation of V. velutina upon honeybees, and potentially on other insects. Honeybee DNA was identified in all types of samples, but larval faecal pellets retrieved the higher number of reads of honeybee DNA and the largest diversity at all taxonomic levels. Over all samples we could identify 4 orders, 9 families, 6 genera and 1 species of prey. We estimate that collecting 6 workers is sufficient to identify honeybee predation by a colony using worker’s jaws. Stomachs were the least useful sample type to detect honeybee DNA. The presence of honeybee DNA in all analysed colonies irrespective of collection site, and the variety of insect orders detected in the diet support current concerns over the acknowledged negative impact of V. velutina on managed honeybees and its potential threat to pollination services provision.

Lichens are classified into different functional groups depending on their ecological and physiological response to a given environmental stressor. However, knowledge on lichen response to the synergistic effect of multiple environmental factors is extremely scarce, although vital to get a comprehensive understanding of the effects of global change. We exposed six lichen species belonging to different functional groups to the combined effects of two nitrogen (N) doses and direct sunlight involving both high temperatures and ultraviolet (UV) radiation for 58 days. Irrespective of their functional group, all species showed a homogenous response to N with cumulative, detrimental effects and an inability to recover following sunlight, UV exposure. Moreover, solar radiation made a tolerant species more prone to N pollution’s effects. Our results draw attention to the combined effects of global change and other environmental drivers on canopy defoliation and tree death, with consequences for the protection of ecosystems.

The merging of community ecology and phylogenetic biology allows us to link broader evolutionary processes to local ecological processes, thereby increasing our understanding of community assembly. A recurrent way to test how species assemblages respond to diferent abiotic conditions and evaluate the role of evolutionary constraints in community assembly is through using environmental gradients as natural treatments. Here, we combine phylogenetic and trait-based methods to evaluate how the phylogenetic diversity and composition of bird assemblages and their community-weighted traits vary along an elevational gradient in the Swiss Alps. For this purpose, we used four life-history traits considered to be key indicators of individual species response to environmental changes: clutch size, number of breeding attempts, dispersal capacity and lifespan. Controlling for phylogeny, we determined whether environmental flters (elevation, habitat type) act on these traits independently of the level of relatedness among species. We found that phylogenetic dispersion decreases with elevation, but the signature of phylogenetic clustering was weak. Phylogenetic fuzzy weighting showed that the distribution of bird species across plots was related to the two environmental gradients; nonetheless, such infuence was not determined by the phylogenetic relationships in either case. That is, there are no specifc clades associated with particular elevation or habitat types. We also found that high elevation communities around the treeline were composed of species with lower reproductive rates, reduced lifespan, and lower dispersal capacity, which would make them less resilient to environmental change. Although traits showed moderate phylogenetic signal, only the lifespan was phylogenetically structured. In the remaining cases, the trait-environment association was not mediated by the phylogenetic relationships among taxa. Our study indicates that evolutionary constraints do not represent a signifcant driver of community assembly in Alpine bird communities and support the notion that phylogeny may often not be a good proxy for traits subject to environmental fltering.

Annually millions of animals are killed as a result of human-wildlife impacts. Each year the NGO Associação Mata Ciliar (NGOMC), in Southeastern Brazil, receives and rehabilitates thousands of animals. We evaluated how natural and anthropogenic characteristics affect the risk of different types of human-wildlife impacts for mammals that arrive at the NGOMC; and explore the relationship between both the animal's size and the type of human-wildlife impact event, survival rates and the likelihood that these animals can be fully rehabilitated. To test our hypotheses regarding the drivers and consequences of the total number of human-wildlife impact events, traffic collisions, electrocutions, and requested removals, we used records of the mammals that arrived at the NGOMC between 2012 and 2018, and obtained data on environmental attributes and anthropogenic factors at the municipality level, as well as species weights. The total number of human-wildlife impact events and of requested removals were both positively correlated with deforestation rate and urban area. The number of traffic collisions was positively related to the number of fires. Municipalities with larger urban areas were more likely to have at least one electrocuted mammal. Temporally, the number of fires two months before was positively correlated with the number of human-wildlife impact events. Traffic collisions and electrocutions more frequently resulted in the death of the animal, than did other events. Animals that died were heavier on average than those that remained in captivity or were successfully released back into the wild. We conclude that human-wildlife impact event rates should decline with lower rates of deforestation, less anthropogenic fires and the adoption of other specific measures to avoid both traffic collisions with fauna and electrocutions.

Population density data on depleted and endangered wildlife species are essential to assure their effective management and, ultimately, conservation. The European wildcat is an elusive and threatened species inhabiting the Iberian Peninsula, with fragmented populations and living in low densities. We fitted spatial capture–recapture models on camera-trap data, to provide the first estimate of wildcat density for Portugal and assess the most influential drivers determining it. The study was implemented in Montesinho Natural Park (NE Portugal), where we identified nine individuals, over a total effort of 3,477 trap-nights. The mean density estimate was 0.032 ± 0.012 wildcat/km2 , and density tended to increase with distance to humanized areas, often linked to lower human disturbance and domestic cat presence, with forest and herbaceous vegetation cover and with European rabbit abundance. Although, this density estimate is within the range of values estimated for protected areas elsewhere in the Iberian Peninsula, our estimates are low at the European level. When put in context, our results highlight that European wildcats may be living in low population densities across the Iberian Mediterranean biogeographic region. No phenotypic domestic or hybrid cats were detected, suggesting potentially low admixture rates between the two species, although genetic sampling would be required to corroborate this assertion. We provide evidence that Montesinho Natural Park may be a suitable area to host a healthy wildcat population, and thus be an important protected area in this species' conservation context.

Esta Newsletter (NL) resulta de uma parceria entre o Instituto de Saúde Baseada na Evidência e a Cochrane Portugal, e tem como objectivo disponibilizar informação sobre áreas interessantes para a prática clínica, com base na melhor evidência científica. São incluídos estudos relevantes, criticamente avaliados pela sua validade, importância dos resultados e aplicabilidade prática, resumidos numa óptica de suporte à decisão. É dada prioridade a estudos de causalidade incluindo-se ainda, quando justificado, estudos qualitativos e metodológicos, assim como revisões científicas. O conteúdo da NL é da exclusiva responsabilidade do(s) seu(s) autor(es).

Metabolic programming controls immune cell lineages and functions, but little is known about γδ T cell metabolism. Here, we found that γδ T cell subsets making either interferon-γ (IFN-γ) or interleukin (IL)-17 have intrinsically distinct metabolic requirements. Whereas IFN-γ+ γδ T cells were almost exclusively dependent on glycolysis, IL-17+ γδ T cells strongly engaged oxidative metabolism, with increased mitochondrial mass and activity. These distinct metabolic signatures were surprisingly imprinted early during thymic development and were stably maintained in the periphery and within tumors. Moreover, pro-tumoral IL-17+ γδ T cells selectively showed high lipid uptake and intracellular lipid storage and were expanded in obesity and in tumors of obese mice. Conversely, glucose supplementation enhanced the antitumor functions of IFN-γ+ γδ T cells and reduced tumor growth upon adoptive transfer. These findings have important implications for the differentiation of effector γδ T cells and their manipulation in cancer immunotherapy.

Objective: To investigate the cutaneous silent period (CSP) by measuring its onset latency, duration and amount signal suppression in patients with motor neuron disease (MND) grouped according to the intensity of upper motor neuron involvement (UMN), and to test the effect of contralateral hand contraction. Methods: Painful stimulation was applied at the V finger, and contraction recorded from the abductor digiti minimi (ADM) muscle (baseline condition). Afterwards, CSP was studied during strong contralateral ADM contraction (test condition). 10-15 consecutive traces were recorded for each condition, signals were rectified, averaged, and analyzed offline. Results: 46 patients were investigated, 15 with progressive muscular atrophy (PMA), 16 with typical amyotrophic lateral sclerosis (ALS), 15 with primary lateral sclerosis/predominant UMN-ALS (PLS+UMN-ALS), and 28 controls. In the baseline condition, all MND groups showed delayed onset latencies (p = 0.001). There was no significant difference in the CSP duration. Suppression was lower in the PLS + UMN-ALS group (p = 0.004). In the control group, contralateral contraction did not change CSP, but onset latency shortened significantly in the PMA group. Conclusions: CSP onset latency is delayed in all investigated groups of MND, including in PMA, indicating subclinical UMN involvement. Changes in CSP can indicate UMN lesion in MND. Significance: CSP should be explored to identify UMN involvement in MND.

Twenty years ago, in the middle 1990s, a pending debate in the RNA cell biology field concerned the nuclear organization of pre-mRNA splicing. Localization studies using antibodies to detect proteins of the spliceosome and oligonucleotide probes that hybridized with the spliceosomal small nuclear RNAs had revealed that practically all building blocks of the splicing machinery were not uniformly distributed in the nucleus but rather appeared concentrated in defined regions. These regions were termed “nuclear speckles” or “splicing domains” due to the local enrichment in splicing factors. Whether or not pre-mRNA splicing occurred within these domains remained controversial.

Eimeria vermiformis is a tissue specific, intracellular protozoan that infects the murine small intestinal epithelia, which has been widely used as a coccidian model to study mucosal immunology. This mouse infection model is valuable to investigate the mechanisms of host protection against primary and secondary infection in the small intestine. Here, we describe the generation of an E. vermiformis stock solution, preparation of sporulated E. vermiformis to infect mice and determination of oocysts burden. This protocol should help to establish a highly reproducible natural infection challenge model to study immunity in the small intestine. The information obtained from using this mouse model can reveal fundamental mechanisms of interaction between the pathogen and the immune response, e.g., provided by intraepithelial lymphocytes (IEL) at the basolateral site of epithelial cells but also a variety of other immune cell populations present in the gut.

Previous results indicated that miR-146b-5p is downregulated by TAL1, a transcription factor critical for early hematopoiesis that is frequently overexpressed in T-cell acute lymphoblastic leukemia (T-ALL) where it has an oncogenic role. Here, we confirmed that miR-146b-5p expression is lower in TAL1-positive patient samples than in other T-ALL cases. Furthermore, leukemia T-cells display decreased levels of miR-146b-5p as compared to normal T-cells, thymocytes and other hematopoietic progenitors. MiR-146b-5p silencing enhances the in vitro migration and invasion of T-ALL cells, associated with increased levels of filamentous actin and chemokinesis. In vivo, miR-146b overexpression in a TAL1-positive cell line extends mouse survival in a xenotransplant model of human T-ALL. In contrast, knockdown of miR-146b-5p results in leukemia acceleration and decreased mouse overall survival, paralleled by faster tumor infiltration of the central nervous system. Our results suggest that miR-146b-5p is a functionally relevant microRNA gene in the context of T-ALL, whose negative regulation by TAL1 and possibly other oncogenes contributes to disease progression by modulating leukemia cell motility and disease aggressiveness.

DNA replication ensures accurate duplication of the original genetic information present in a cell in order for it to be properly transmitted to daughter cells. However, replication can be perturbed, for instance in rapidly dividing cancer cells, in a process referred to as replication stress (RS). Checkpoint kinase 1 (CHK1) is an essential component of the ATR-dependent DNA damageresponse pathway that protect cells from RS by preventing replication fork collapse and activating homologous DNA repair. The ATR-CHK1 pathway is triggered upon exposure of single-stranded DNA that arises with the stalling of replication forks, and it is required to reset proper origin firing, and to promote fork stability and checkpoint activation, delaying mitosis until replication is completed and thereby avoiding mitotic catastrophe.

Ultrasound (US) is a physical property, designated as such when the oscillating sound pressure is above the upper limit of the human hearing rate (20 kHz), and has been explored in many areas of the human activity, from military life to medicine. Medical ultrasonography is able to capture size and structure of internal organs, tendons, muscle and nerves, it does not involve the use of ionizing radiation, and in addition is rapid and costs are relatively low. In neuromuscular disorders, US was first used as a treatment option for pain.

Murid γ-herpesvirus-4 (MuHV-4) promotes polyclonal B cell activation and establishes latency in memory B cells via unclear mechanisms. We aimed at exploring whether B cell receptor specificity plays a role in B cell susceptibility to viral latency and how this is related to B cell activation. We first observed that MuHV-4-specific B cells represent a minority of the latent population, and to better understand the influence of the virus on non-MuHV-4 specific B cells we used the SWHEL mouse model, which produce hen egg lysozyme (HEL)-specific B cells. By tracking HEL+ and HEL- B cells, we showed that in vivo latency was restricted to HEL- B cells while the two populations were equally sensitive to the virus in vitro. Moreover, MuHV-4 induced two waves of B cell activation. While the first wave was characterized by a general B cell activation, as shown by HEL+ and HEL- B cells expansion and upregulation of CD69 expression, the second wave was restricted to the HEL- population, which acquired germinal center (GC) and plasma cell phenotypes. Antigenic stimulation of HEL+ B cells led to the development of HEL+ GC B cells where latent infection remained undetectable, indicating that MuHV-4 does not benefit from acute B cell responses to establish latency in non-virus specific B cells but relies on other mechanisms of the humoral response. These data support a model in which the establishment of latency in B cells by γ-herpesviruses is not stochastic in terms of BCR specificity and is tightly linked to the formation of GCs.

Aim: In this narrative review we aimed to describe how stroke affects emotions and update the readers on the emotional disturbances that occur after stroke. Methods: We searched Medline from 1.1.2013 to 1.7.2019, personal files and references of selected publications. All retrieved systematic reviews and randomized controlled trials were included. Other references were selected by relevance. Summary of review: The emotional response includes a reactive behavior with arousal, somatic, motivational and motor components, and a distinctive cognitive and subjective affective experience. Emotional category responses and experiences after stroke can show dissociations between the behavioral response and the cognitive and affective experiences. Emotional disturbances that often occur after stroke include fear, anger, emotional indifference, lack of understanding of other emotions, and lack of control of emotional expression. Emotional disturbances limit social reintegration of the persons with stroke and are a source of caregiver burnout. The evidence to support the management of the majority of emotional disorders in stroke survivors is currently weak and of low or very low methodologic quality. An exception are the disorders of emotional expression control where antidepressants can have a strong beneficial effect, by reducing the number and duration of the uncontrollable episodes of crying or laughing. Conclusion: Our current knowledge of the emotional disorders that occurs in acute stroke patients and in stroke survivors is heterogeneous and limited. Joint efforts of different research approaches, methodologies and disciplines will improve our current understanding on emotional disorder after stroke and indicate rational pathways to manage them.

Em 2018, a Sociedade Portuguesa de Antropologia e Etnologia (SPAE) celebrou o seu centenário. Nessa altura fui curadora, juntamente com Vítor Oliveira Jorge (arqueólogo, professor aposentado e presidente da SPAE), da exposição A Sociedade Portuguesa de Antropologia e Etnologia, 1918-2018: 100 anos ao serviço da ciência, que decorreu, entre 19 de Novembro de 2018 e 11 de Janeiro de 2019, na Faculdade de Letras da Universidade do Porto (FLUP). Essa ocasião permitiu-me reflectir sobre a contribuição da SPAE para a institucionalização académica da antropologia e o seu papel público como espaço para a difusão do conhecimento, debate e troca de ideias. Como se tratava de dar conta de 100 anos de actividade, foi feita uma selecção de alguns dos seus aspectos principais, ou que mais se destacaram, tal como farei neste texto.

Este ensaio retoma os itinerários planeados e percorridos pelo cientista social brasileiro Gilberto Freyre no império colonial português, entre outubro de 1951 e janeiro de 1952. No decorrer da viagem, Freyre apresentou o conceito de luso-tropicalismo, que o regime do Estado Novo português viria a reutilizar para fins político-ideológicos, interna e externamente, nos anos seguintes, com o acordo ou tolerância da Oposição democrática, e que continuou a ecoar na sociedade portuguesa, após o fim da ditadura e do colonialismo, até aos nossos dias1. Da visita resultaram dois livros: Um Brasileiro em terras portuguesas e Aventura e rotina (ambos de 1953). O primeiro, como o subtítulo esclarece, pretende ser uma «introdução a uma possível luso-tropicologia », acompanhada de conferências e discursos proferidos durante o percurso. O segundo é uma espécie de diário da viagem realizada «à procura das constantes portuguesas de carácter e acção»

Quando, há mais de dez anos atrás, comecei a interessar-me pelo estudo das relações entre Portugal e o Brasil deparei com uma espécie de vazio historiográfico no período que separa o entorno da independência brasileira e os anos 20 já do século XX. E, no entanto, quanto mais lia e investigava sobre o tema, mais me apercebia o quanto das reconfigurações da ideia imperial portuguesa se mantiveram sustentadas em paradigmas herdados do decomposto império luso-brasileiro, não só através da tradição, mas também da imaginação. Na minha pesquisa de doutoramento, que culminou na tese Espelho Fraterno: o Brasil e o republicanismo português na transição para o século XX (2013) que tive a honra de ver premiada com o prémio Vítor de Sá, concentrei-me na dimensão republicana dessa imaginação imperial e consequentemente foquei-me sobretudo nas duas décadas que medeiam os adventos das repúblicas brasileira e portuguesa, 1889 e 1910, respetivamente.

O tropicalismo arranca em 1967, através do corpo: a música de Caetano Veloso e Gilberto Gil, os vestíveis de Hélio Oiticica, as propostas teatrais de José Celso Martinez Corrêa e os cenários de Hélio Eichbauer. Hoje as coisas são um pouco mais complexas. Em tempo de redes sociais, os aspirantes ao poder fazem uso da sua imediatez para suscitarem reações epidérmicas, superficiais, populistas e de grande instantaneidade. A boçalidade triunfa nas caixas de comentários, e com mais alguns perfis falsificados podem manipular-se plebiscitos, movimentos secessionistas, ou, e também censurar-se exposições de arte. Nesta variação do fascismo, a epiderme eletrificada das redes sociais estrutura-se como uma poderosa arena onde se aparenta uma falsa democracia. Talvez a arte continue a ser um reduto para reflexão, mas vemos que a censura se manifesta hoje de modo talvez mais eficaz, silenciando artistas e professores, através da pressão mediatizada, da emoção do momento. Para isto é necessária a atenção consciente da arte, dos artistas, e também dos arte-educadores: enfrenta-se uma massa cada vez mais informe, alienada e despojada de reflexão para além do imediato.