Abstract Background Although older adults are at a high risk of severe or critical Covid-19, there are many cases of unvaccinated centenarians who had a silent infection or recovered from mild or moderate Covid-19. We studied three Brazilian supercentenarians, older than 110 years, who survived Covid-19 in 2020 before being vaccinated. Results Despite their advanced age, humoral immune response analysis showed that these individuals displayed robust levels of IgG and neutralizing antibodies (NAbs) against SARS-CoV-2....

Abstract Background The development of multidrug resistance (MDR) associated with the overexpression of the efflux transporters Mdr1 and Cdr1 in Candida species impedes antifungal therapies. The urgent need for novel agents able to inhibit the function of both pumps, led us to evaluate this property in 137 extracts obtained from Argentinian plants. Methods The ability of the extracts to reverse efflux pump-mediated MDR was determined with an agar chemosensitization assay using fluconazole (FCZ) resistant Mdr1-...

The body armor of ankylosaurians is a unique morphological feature among dinosaurs. Despite being studied for decades, paleohistological analyses have only started to uncover the details of its function. Yet, there has been an overall bias toward sampling ankylosaurian remains from the Northern Hemisphere and limited quantitative studies on the morphological and functional evolution. Here, we describe new ankylosaurian materials recovered from the Late Cretaceous of Antarctica that, in combination with data compiled from the...

Objectives: Inborn error of immunity (IEI) comprises a broad group of inherited immunological disorders that usually display an overlap in many clinical manifestations challenging their diagnosis. The identification of disease-causing variants comprises the gold-standard approach to ascertain IEI diagnosis. The efforts to increase the availability of clinically relevant genomic data for these disorders constitute an important improvement in the study of rare genetic disorders. This work aims to make available whole-exome sequencing (WES) data of...

Background: Phenotypic diversity among populations may result from divergent natural selection acting directly on traits or via correlated responses to changes in other traits. One of the most frequent patterns of correlated response is the proportional change in the dimensions of anatomical traits associated with changes in growth or absolute size, known as allometry. Livebearing fishes subject to predation gradients have been shown to repeatedly evolve larger caudal peduncles and smaller cranial regions under high...

Several studies indicate that the activity of cruzipain, the main lysosomal cysteine peptidase of Trypanosoma cruzi, contributes to parasite infectivity. In addition, the parasitic invasion process of mammalian host cells is described to be dependent on the activation of the host TGF-β signaling pathway by T. cruzi. Here, we tested the hypothesis that cruzipain could be an important activator of latent TGF-β and thereby trigger TGF-β-mediated events crucial for the development of Chagas disease. We...

Two new species of the genus Isotomiella Bagnall, 1939 are described and illustrated, the first: Isotomiella macedoi sp. n., based on males and females, from the “Parque Nacional da Serra dos Órgãos” (Teresópolis municipality, State of Rio de Janeiro) differs from the other by tibiotarsus III thickened and blunt and two antero-lateral chaetae of labrum strongly thickened. The second species Isotomiella uai sp. n. from “Serra da Gandarela”, (Caeté municipality, State of Minas Gerais) differs...

The mere presence of predators (i.e., predation risk) can alter consumer physiology by restricting food intake and inducing stress, which can ultimately affect prey-mediated ecosystem processes such as nutrient cycling. However, many environmental factors, including conspecific density, can mediate the perception of risk by prey. Prey conspecific density has been defined as a fundamental feature that modulates perceived risk. In this study, we tested the effects of predation risk on prey nutrient stoichiometry (body and...

Most conservation decisions take place at national or finer spatial scales. Providing useful information at such decision-making scales is essential for guiding the practice of conservation. Brazil is one of the world’s megadiverse countries, and consequently decisions about conservation in the country have a disproportionate impact on the survival of global biodiversity. For three groups of terrestrial vertebrates (birds, mammals, and amphibians), we examined geographic patterns of diversity and protection in Brazil, including that of...

Genes of major phenotypic effects and strong genetic correlations can facilitate adaptation, direct selective responses and potentially lead to phenotypic convergence. However, the preponderance of this type of genetic architecture in repeatedly-evolved adaptations remains unknown. Using hybrids between Haplochromis chilotes (thick-lipped) and H. nyererei (thin-lipped) we investigated the genetics underlying hypertrophied lips and elongated heads, traits that evolved repeatedly in cichlids. At least 25 loci of small-to-moderate and mainly additive effects were detected. Phenotypic variation...

The leaf anatomy of nine species of Manihot Mill. were studied with the objective of finding anatomical features that contribute to understanding the taxonomy of the genus. Leaf samples were collected in the field and from herbarium specimens, and standardized methods were used for both light and scanning electron microscopy. The following species were studied: M. bellidifolia P. Carvalho & M. Martins, M. brachyandra Pax & K. Hoffm., M. caerulescens Pohl, M. diamantinensis Allem, M....

Aim: Understanding the complex interaction and relative contributions of factors involved in species and trait diversification is crucial to gain insights into the evolution of Neotropical biodiversity. Here, we investigated the drivers of morphological variation in bromeliads along a latitudinal gradient in a biodiversity hotspot. Location: Atlantic Forest, Brazil. Taxon: A species complex in the genus Vriesea (Bromeliaceae). Methods: We measured shape and size variation for 208 floral bracts and 176 leaves in individuals from...

The family Bromeliaceae is essentially Neotropical, with high endemism and diversity in the Atlantic Rainforest Domain. Species circumscription is a major problem in the family systematics, especially in the most diverse genera. Species of the Vriesea procera complex, which occur in forests and restinga (coastal vegetation) along the South American Atlantic coast from Venezuela to southern Brazil, share the same basic vegetative and reproductive morphological patterns. However, they vary widely in the number and position...

It is well known that bird richness in the Amazon is greater in upland forests and that seasonally flooded forest is particularly species poor. However, the misleading pattern of greater bird richness in seasonally flooded forest has emerged seemingly unnoticed numerous times in richness maps in the literature. We hypothesize that commission errors in digital distribution maps (DDMs) are the cause behind the misleading richness pattern. In the Amazon, commission errors are a consequence of...

Maximum sizes attained by living actinopterygians are much smaller than those reached by chondrichthyans. Several factors, including the high metabolic requirements of bony fishes, have been proposed as possible body-size constraints but no empirical approaches exist. Remarkably, fossil evidence has rarely been considered despite some extinct actinopterygians reaching sizes comparable to those of the largest living sharks. Here, we have assessed the locomotion energetics of Leedsichthys problematicus, an extinct gigantic suspension-feeder and the largest actinopterygian...

Climate change and biodiversity loss are expected to simultaneously affect ecosystems, however research on how each driver mediates the effect of the other has been limited in scope. The multiple stressor framework emphasizes non-additive effects, but biodiversity may also buffer the effects of climate change, and climate change may alter which mechanisms underlie biodiversity-function relationships. Here, we performed an experiment using tank bromeliad ecosystems to test the various ways that rainfall changes and litter diversity...

1. Despite ongoing research in food web ecology and functional biogeography, the links between food-web structure, functional traits and environmental conditions across spatial scales remain poorly understood. Trophic niches, defined as the amount of energy and elemental space occupied by species and food webs, may help bridge this divide. 2. Here, we ask how the functional traits of species, the environmental conditions of habitats and the spatial scale of analysis jointly determine the characteristics of...

Phenotypic variation among populations, as seen in the signaling traits of many species, provides an opportunity to test whether similar factors generate repeated phenotypic patterns in different parts of a species’ range. We investigated whether genetic divergence, abiotic gradients, and sympatry with closely related species explain variation in the dewlap colors of Amazon Slender Anoles, Anolis fuscoauratus. To this aim, we characterized dewlap diversity in the field with respect to population genetic structure and evolutionary...

Biofilm-associated polymicrobial infections tend to be challenging to treat. Candida albicans and Staphylococcus aureus are leading pathogens due to their ability to form biofilms on medical devices. However, the therapeutic implications of their interactions in a host is largely unexplored. In this study, we used a mouse subcutaneous catheter model for in vivo-grown polymicrobial biofilms to validate our in vitro findings on C. albicans-mediated enhanced S. aureus tolerance to vancomycin in vivo. Comparative assessment of...

The record of unenlagiines in Brazil, except for one dorsal vertebra, is still under debate based on isolated teeth. Here, we describe Ypupiara lopai gen. et sp. nov., the first undoubtful nominal unenlagiine dromaeosaurid species from Brazil, from the Marília Formation (Maastrichtian), Bauru Group, Paraná Basin. The specimen comprises a partial right maxilla (with three teeth in loci) and a right dentary. Ypupiara is characterized by the morphology of the maxilla, presenting restrict number of...

Despite the widespread use of Ecological Niche Models (ENMs) for predicting the responses of species to climate change, these models do not explicitly incorporate any population-level mechanism. On the other hand, mechanistic models adding population processes (e.g., biotic interactions, dispersal and adaptive potential to abiotic constraints) are much more complex and difficult to parameterize, especially if the goal is to predict range shifts for many species simultaneously. In particular, the adaptive potential (based on genetic...

1.Traditionally, trait‐based studies have explored single‐trait‐fitness relationships. However, this approximation in the study of fitness components is often too simplistic, given that fitness is determined by the interplay of multiple traits, which could even lead to multiple functional strategies with comparable fitness (i.e. alternative designs). 2.Here we suggest that an analytical framework using boosted regression trees (BRT) can prove more informative to test hypotheses on trait combinations compared to standard linear models. We use two...

More than one third of the bird species found in the Caribbean are endemic to a set of neighboring islands or a single island. However, we have little knowledge of the evolutionary history of the Caribbean avifauna and the lack of phylogenetic studies limits our understanding of the extent of endemism in the region. The Sharp-shinned Hawk (Accipiter striatus) occurs widely across the Americas and includes three endemic Caribbean taxa: venator on Puerto Rico, striatus...

The consequences of the introduction of invasive plants for the diet of herbivorous insects have been little explored in nature where, potentially, abiotic and biotic factors operate. In this study we examined the larval performance of two Neotropical Danaini butterflies when using either a native or an exotic Apocynaceae species as host plant in both field and laboratory experiments. Hosts greatly differ in their amount of latex exudation and other physicochemical traits, as well as...