21587 research outputs found
Sort by
Fidaxomicin for Clostridiodes difficile infection in inflammatory bowel disease: a multicenter retrospective cohort study
No full textInflammatory bowel disease (IBD) patients with Clostridiodes difficile Infection (CDI) are at increased risk of disease exacerbations, therapy escalation, colectomy, and mortality. Data on fidaxomicin use in IBD patients with CDI are very limited. We aimed to assess the effectiveness and safety of fidaxomicin for CDI and its impact on IBD outcomes in a large retrospective multicenter cohort stud
Stone selection by wild chimpanzees shares patterns with Oldowan hominins
No full textThe use of broad tool repertoires to increase dietary flexibility through extractive foraging behaviors is shared by humans and their closest living relatives (chimpanzees, Pan troglodytes). However, comparisons between tool use in ancient human ancestors (hominins) and chimpanzees are limited by differences in their toolkits. One feature shared by primate and hominin toolkits is rock selection based on physical properties of the stones and the targets of foraging behaviors. Here, we document the selectivity patterns of stone tools used by wild chimpanzees to crack nuts at Bossou, Guinea, through controlled experiments that introduce rocks unknown to this population. Experiments incorporate specific rock types because previous studies document hominin selection of these lithologies at Kanjera South 2 Ma. We investigate decisions made by chimpanzees when selecting stones that vary in their mechanical propertiesdfeatures not directly visible to the individual. Results indicate that the selection of anvils and hammers is linked to task-specific mechanical properties. Chimpanzees select harder stones for hammers and softer stones for anvils, indicating an understanding of specific properties for distinct functions. Selectivity of rock types suggests that chimpanzees assess the appropriate materials for functions by discriminating these 'invisible' properties. Adults identify mechanical properties through individual learning, and juveniles often reused the tools selected by adults. Selection of specific rock types may be transmitted through the reuse of combinations of rocks. These patterns of stone selection parallel what is documented for Oldowan hominins. The processes identified in this experiment provide insights into the discrete nature of hominin rock selection patterns in Plio-Pleistocene stone artifact production.BCS-1460502; MEXT-1600200
Hot and toxic: accumulation dynamics and ecotoxicological responses of mussel Mytilus galloprovincialis exposed to marine biotoxins during a marine heatwave
No full textClimate change is increasing marine heatwaves (MHWs) frequency and severity worldwide. These extreme events often cause bivalves' mass mortality and facilitate the growth, proliferation and dispersion of toxinproducing microalgae blooms associated with threats to seafood safety. Yet, the interactive effects between MHW and uptake of marine biotoxins by biota are a novel topic still lacking thorough research, from both the ecotoxicological and seafood safety standpoints. This study assessed the effects of a MHW event on the accumulation/elimination dynamics of diarrhetic shellfish toxins in Mytilus galloprovincialis exposed to Prorocentrum lima and the ecotoxicological responses of mussels co-exposed to these two stressors. Results showed that acute exposure to +4 degrees C reduced toxins accumulation (-49 %) and elimination (-77 %) compared to control temperature. Moreover, exposure to MHW and toxins affected mussels' antioxidant activity, lipid and protein damage, and metabolism in a tissue-specific manner. These findings highlight that M. galloprovincialis can face higher vulnerability to toxins when MHW events strike
Within and beyond: chert pocurement patterns during the upper palaeolithic in Southwesternmost Iberia
No full textAnalyses of raw materials and the distinction between local/regional and long-distance sources have proven invaluable for understanding the extensive movements, interactions, and social networks during the Upper Palaeolithic in the Iberian Peninsula. However, unlike other parts of Iberia, research on the management and acquisition of raw materials in the south and west of Iberia remains relatively underdeveloped. Despite significant knowledge about the technological practices of Palaeolithic hunter-gatherers from southern Portugal, particularly from studies conducted at the site of Vale Boi, there is a noticeable lack of focus on raw materials management. This paper presents the first comprehensive characterisation of chert raw materials from the Gravettian, Proto-Solutrean, and Solutrean occupations at Vale Boi, using both macroscopic and petrographic techniques. Our study reveals that the majority of chert found at Vale Boi originates locally, within a 20 km radius. However, a non-negligible portion of the chert comes from non-local sources, indicating > 200 km raw material circulation from central Portugal and southern Spain.2020.08722.BD; DL57/2016/CP1361/CT002
Environmental impact and costs of a switching program of intravenous to subcutaneous infliximab in Inflammatory Bowel Disease
No full textWe aimed to compare real-life direct and indirect costs and the environmental impact of switching IBD patients from IV to SC infliximab (IFX)
Developing epidemiological preparedness for a plant disease invasion: modelling citrus huánglóngbìng in the European Union
No full textSocietal Impact Statement Huanglongbing (HLB) is a bacterial disease of citrus that has significantly impacted Brazil and the United States, although citrus production in the Mediterranean Basin remains unaffected. By developing a mathematical model of spread in Spain, we tested surveillance and control strategies before any future HLB entry in the EU. We found while some citrus production might be maintained by roguing, this requires extensive surveillance and significant chemical control, perhaps also including testing of psyllids (which spread the pathogen) for bacterial DNA. Our work highlights the key importance of early detection (including asymptomatic infection) and vector control for HLB management. Summary Huanglongbing (HLB; citrus greening) is the most damaging disease of citrus worldwide. While citrus production in the United States and Brazil have been affected for decades, HLB has not been reported in the European Union (EU). However, a HLB vector, the African citrus psyllid, is already in Portugal and Spain. In 2023, the major vector, the Asian citrus psyllid, was first reported in Cyprus. We develop a landscape-scale, epidemiological model, accounting for heterogeneous citrus cultivation and vector dispersal, as well as climate and disease management. We use our model to predict HLB dynamics for an epidemic vectored by the African citrus psyllid in high-density citrus areas in Spain, assessing detection and control strategies. Without disease management, we predict large areas infected within 10-20 years. Even with significant visual surveillance, any epidemic will be widespread on first detection, making eradication unlikely. Nevertheless, increased inspection and roguing following first detection, particularly if coupled with intensive insecticide use, could sustain some citriculture for a decade or more, albeit with reduced production. However, effective control may require chemical application rates and/or active substances no longer authorised in the EU. Strategies targeting asymptomatic infection will be more successful. Detection of bacteriliferous vectors-sometimes possible long before plants show symptoms-could reduce lags before disease management commences. If detection of HLB-positive vectors were followed by intensive insecticide sprays, this may greatly improve outcomes. Our work highlights modelling as a key component of developing epidemiological preparedness for a pathogen invasion that is, at least somewhat, predictable in advance
Scales of toolstone transport in the Armenian Highlands during MIS 3: The contribution of Ararat-1 Cave (Ararat Depression) to reconstructing opportunities for social interactions
No full textMarine Isotope Stage (MIS) 3, ranging from around 57,000 to 29,000 years ago, is a period of significant archaeological interest due to notable transitions in lithic technology and hominin populations. In Europe, this time saw the replacement of Middle Palaeolithic (MP) technologies associated with Neanderthals by Upper Palaeolithic (UP) technologies linked to anatomically modern humans (AMHs). This technological shift is conventionally attributed to a demographic turnover; however, the timing of this transition varied regionally. The presence of Neanderthals and AMHs in the Levant, western Europe, and elsewhere over extended periods complicates the narrative, suggesting asynchronous and regionally diverse associations of hominin species and lithic technologies. This study shifts the attention to potential technological and cultural transmissions among MP- and UP-making groups, emphasizing the roles of social and exchange networks. Recent data from the obsidian-rich Armenian Highlands enable us to consider the mobility and land use of these groups without the added complication of toolstone with different knapping qualities, so patterns more clearly reflect mobility patterns, land use strategies, and potential social connections of foraging groups. These results suggest that, while MP-making groups in MIS 3 had overlapping territories, the UP-making groups at Aghitu-3 had smaller movements on the landscape. In contrast, MIS 2 sites with UP lithic assemblages have resource territories that apparently overlapped much like those of the MIS 3 MP sites. The findings hint at the possibility that differing mobility and land use during MIS 3 might have contributed to the coexistence of distinct lithic technologies, potentially through social transmission rather than a direct replacement of hominin populations
Not regionally extinct: rediscovery of ruppia drepanensis in Portugal, the westernmost range edge in Europe
No full textRuppia drepanensis Tineo ex Guss. is an important habitat-forming aquatic plant in saline and brackish Mediterranean wetlands. The species is declining in several parts of its range due to hydrological changes and habitat degradation. R. drepanensis was considered Critically Endangered, possibly Regionally Extinct in Portugal, due to not being observed since 1986 despite extensive surveys of suitable habitat. We report on a new population, the westernmost known record for the species in Europe, identified with morphological and molecular data. Despite being inside a protected area, this population occupies a single small pond adjacent to a road, making it vulnerable to habitat changes. Ex situ conservation is recommended, including seed banking and/or the establishment of new populations.SFRH/BD/147343/2019; LIFE23-NAT-PT-RESTORESEAGRASS/10114824
Skin mucus and blood plasma as non-lethal sources of malnutrition protein biomarkers in meagre (Argyrosomus regius)
No full textDeveloping dietary formulations for aquaculture that meet nutritional requirements is essential to production, as nutrition is key for fish growth and health. However, novel dietary formulations may induce malnutrition, which is complex to evaluate and often requires animal sacrifice. Therefore, finding reliable non-lethal biomarkers to diagnose malnutrition in fish is important. This study aimed to obtain vital information on potential non-lethal biomarkers from blood plasma and skin mucus to assess the fish's nutritional status using meagre (Argyrosomus regius) juveniles. For that purpose, a nutritional challenge was performed with fish fed a fish meal (FM) and fish- oil (FO) based control diet (55.1 % FM; 11 % FO, CTRL), a challenging diet (15 % FM; 7 % FO, CD), and a highly challenging diet (5 % FM; 5 % FO, ED), which, despite being nutritionally complete, may pose digestive and physiological challenges to carnivorous species. Diets significantly affected blood parameters, except for leukocyte counts, peroxidase activity, and immunoglobulin levels. Overall, blood parameters showed potential as non-lethal biomarkers to accurately identify signs of malnutrition. Meagre's plasma and skin mucus proteomes provided crucial information on the species' reaction to malnutrition, and 29 proteins connected to various physiological functions such as metabolism, development and immunity showed potential as non-lethal biomarkers. Significance: The significance of this study lies in the establishment of potential non-lethal biomarkers for diagnosing malnutrition in fish. The results demonstrate that immunological, haematological, and biochemical parameters measured in fish blood can reveal signs of nutritional deficiencies. The findings further highlight that the proteomes of plasma and skin mucus provide valuable information about the fish's nutritional status. Notably, 29 proteins identified in this study, associated with various physiological functions, exhibit biomarker potential and warrant consideration in future research in the field of aquaculture nutrition. Moreover, the research provides critical insights into the proteome of meagre (Argyrosomus regius), enhancing our understanding of the species and contributing to the future improvement of its aquaculture production.projects EMBRC.PT [ALG-01-0145-FEDER-022121] and BIODATA.PT [ALG-01-0145-FEDER-022231]; project INOVAQUA [MAR-021.1.3-FEAMPA-00004]; UI/BD/150902/202
Modulation of biofilm growth by shear and fluctuations in turbulent environments
No full textThis work investigates the role of shear and turbulent fluctuations on multi-species biofilm growth. The study is mostly motivated by understanding biofouling on microplastics (MPs) in oceanic environments. By increasing particle stickiness, biofilms promote MP aggregation and sinking; therefore, a thorough understanding of this multi-scale process is crucial to improve predictions of the MPs fate. We conducted a series of laboratory experiments using an oscillating-grid system to promote biofilm growth on small plastic surfaces under homogeneous isotropic turbulence with grid Reynolds numbers between 305 and 2220. Two configurations were analyzed: one where plastic samples move along with the grid (shear-dominated) and another one where the samples are kept fixed downstream the grid, thus experiencing turbulence but no mean flow (shear-free). Biofilm formed in all cases in a time scale of days, then the biomass formed on the plastic pieces was carefully measured and analyzed as a function of the turbulence level. The shear-free results were further interpreted using a parsimonious physical model, coupling the nutrient uptake rate within the biofilm (Monod kinetics) with the turbulent diffusion of the surrounding bulk liquid. Results show that: (i) under shear-dominated conditions, the biofilm mass initially grows with turbulence intensity before decaying, presumably due to shear-induced erosion; (ii) in the shear-free experiments, the mass increases monotonically following an enhanced availability of nutrients, and then saturates due to uptake-limited kinetics. This latter behavior is well reproduced by the physical model. Furthermore, a subset of plastic pieces were analyzed with a scanning electron microscope, revealing that turbulence also affects the microscopic configuration of biofilm clusters, increasing their compactness as the amplitude of turbulent fluctuations increases. These results contribute not only to our fundamental understanding of biofilms under flow, but can also inform global models of MP transport in marine environments.TRITON project (TED2021-132623A-I00