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The “Critically Endangered” Cherry-throated Tanager Nemosia rourei is endemic to the Atlantic Forest of south-eastern Brazil, and extremely rare for reasons that are not yet fully understood. We monitored reproductive activities of the only known individuals of the species, at two sites, between October 2018 and November 2023. The birds foraged in social groups of 5–8 individuals. Ten nests, built in trees at heights of 12–26 m, were monitored through continuous direct observation. Most reproductive activity occurred between October and end of November, with one further nest found in March. Clutch size was 3–4 eggs, the incubation and nestling periods were 16 days, and the chicks were fed mainly on invertebrates. Up to six nest helpers, likely young from previous seasons, assisted with the collection of nest material, feeding the chicks, and defending the nest. Reproductive success was 50%, with losses due to climatic conditions (rain and cold) and predation, but may have been enhanced by the efforts of the researchers in scaring away potential predators including Spot-billed Toucanet Selenidera maculirostris and Black Capuchin Sapajus nigritus. These findings reinforce the value of detailed observation of social groups and their nests, and continuing efforts to deter predators. Further research could address how parental care and nest helpers affect reproductive success. The availability of large trees with abundant lichens may be a limiting factor for the reproductive success of species in the long term, and so protecting and restoring habitat with such features is crucial for the long-term conservation of this species.
Understanding the interplay between adiposity and histopathological features of colorectal tumours is crucial for advancing strategies in disease management. We conducted a retrospective cohort study over an 8-year period (2007–2015), including patients who underwent surgical resection for colorectal cancer (CRC). Body composition was assessed via computed tomography (CT) at the level of the third lumbar vertebra, with visceral adipose tissue (VATd) and subcutaneous adipose tissue (SATd) radiodensities stratified into tertiles. Systemic inflammatory status was evaluated using the neutrophil-to-lymphocyte ratio (NLR). Logistic regression was employed to analyse the relationship between variables, using OR with 95 % CI. The Cox proportional hazards model assessed hazard ratios (HR) with 95 % CI. A total of 231 patients were included (48·9 % men, 51·1 % women), with 93·6 % in CRC stages II and III. Multivariate analyses demonstrated that CRC stages II and III (OR = 5·15, 95 % CI: 1·60, 16·62; OR = 5·16, 95 % CI: 1·59, 16·77) and low VATd (1st and 2nd tertiles; OR = 2·43, 95 % CI: 1·30, 4·53) were associated with the presence of desmoplasia. In the multivariate Cox analyses, only stage III disease (HR = 4·77, 95 % CI: 1·09, 20·89) and moderate to accentuated fibrous stroma (HR = 1·90, 95 % CI: 1·03, 3·46) were identified as predictors of reduced overall survival. These findings suggest that increased visceral adiposity may contribute to the development of a desmoplastic tumour microenvironment. Moreover, the presence of moderate to accentuated fibrous stroma is significantly associated with poorer long-term survival in patients with CRC.
Ochoterenella is a large group of filarial parasites of anurans distributed throughout Central and South America. In the present study, we describe a new species of Ochoterenella parasitizing 2 frogs, Boana geographica and Boana multifasciata, from different localities in the Brazilian Amazon. The main morphological traits that differ Ochoterenella casiraghii n. sp. from its congeners are the smaller body size, a shorter cephalic plate, smaller parastomal structures, and the small, short and rounded cuticular bosses on the body of both sexes. The females have a shorter ovejector, and the number of caudal papillae distinguishes males. Pairwise sequence comparisons of the new species reveal a high level of divergence from Ochoterenella spp. Our phylogenetic analyses, based on cox1 and concatenated partial mitochondrial genes, support the monophyly of all subfamilies and genera examined herein. The new species represents the 17th in the Ochoterenella genus and a new parasite record for both anuran species. We provide the first ultrastructural description of the species in the genus and establish the phylogenetic relationships of the new species among parasites of amphibians and reptiles from the Onchocercidae.
Aplectana membranosa is a cosmocercid nematode that shows affinity with various amphibian and reptile hosts, being considered a generalist species. To date, no studies have investigated the influence of host and locality in the morphological variation of this species. Thus, we analysed morphological and morphometric characters of 260 specimens of A. membranosa collected from 9 host species and 7 different localities. To complement the metric studies, we conducted phylogenetic analyses using the ribosomal genes 28S and internal transcript spacer 1 (ITS1) to determine the phylogenetic position of the species and its divergence. In the present study, it was possible to observe the cloacal papillae pattern of the species through scanning electron microscopy, and we found no morphological variation in the specimens of A. membranosa from various hosts in different localities in Brazil. The study showed low variation in all data. However, despite the low variation, we found that external environmental conditions, such as climate and latitude, influence its variation. Molecular analyses highlighted that the separation of Cosmocercidae members may be related to geographic distribution and population genetic divergence. Thus, the results illustrated in this study reiterate the importance of using integrative data to better elucidate the family’s taxonomic and evolutionary history.
Understanding the population structure and genetic diversity of green turtles is crucial for effective conservation. This study investigated the occurrence, genetic composition, and potential origins of green turtles (Chelonia mydas) in the Potiguar Basin, northeastern Brazil, based on stranding data from 2010 to 2019. Analysis revealed that 87.36% of the population consisted of juveniles, primarily females with a curved carapace length (CCL) between 30 and 59.9 cm. Genetic analysis of the mtDNA control region (481 bp, n = 39) revealed eight haplotypes, with CM-A8 (48.7%) and CM-A5 (30.8%) being the most common. This may be related to the geographic position of the Potiguar Basin, located in the ‘corner’ of the South American continent. High haplotype diversity and low nucleotide diversity were observed, consistent with other Brazilian foraging grounds. Mixed stock analysis identified Ascension Island as the primary source population, followed by Guinea-Bissau and Surinam. The results highlight the importance of the Potiguar Basin as a foraging area for green turtles and emphasize the need for comprehensive conservation strategies to protect this vulnerable population.
Elevated levels of IL-6 in plasma are associated with the severity of visceral leishmaniasis (VL). The clinical manifestations of VL vary among patients, influenced by host factors and the virulence of the Leishmania infantum parasite. Considering that severe VL may result from an exaggerated inflammatory response, this study investigated whether IL-6 could serve as a biomarker to identify pro-inflammatory virulence factors. We conducted a genome-wide association study (GWAS) analysis on L. infantum isolates from patients with VL, whose IL-6 concentrations were measured. The analysis revealed that the relationship between IL-6 levels and clinical outcomes (survival vs mortality) had an area under the curve (AUC) of 0.67 (95% CI 0.52–0.81). A cut-off of 391.7 pg mL−1 for IL-6 was established to conduct a logistic regression analysis. We identified 10 029 single nucleotide variants (SNVs) across 62 genomes, resulting in 6,948 SNVs after filtering, of which 6,341 are located in protein-coding regions. The association analysis with PLINK identified 722 variants, of which 35 showed significant associations, with odds ratios ≥3.3, primarily in coding regions. These findings demonstrate that IL-6 levels tended to be associated with the fatal outcome of VL and highlight 35 novel genetic variants that could serve as potential biomarkers for prognosis. Further research into the biological role of these variants may lead to new therapeutic targets and improve the clinical management of VL, especially in identifying high-risk patients.
Schrankiana are gastrointestinal parasites of anurans, distributed throughout Central and South America. Schrankiana formosula and Schrankiana inconspicata are some of the most commonly reported species parasitising anurans from Brazil, and the morphological differences between them are unclear. In the present study, we redescribed S. formosula based on a re-examination of type series and newly collected material from the frog Leptodactylus pentadactylus in the state of Amapá, Brazil. Additionally, we re-examined the type series of S. inconspicata, and propose it as a junior synonym of S. formosula. We provide detailed morphological and morphometric data with intraspecific variation analyses and new molecular data for S. formosula. In the present phylogeny, S. formosula formed a well-supported clade with Raillietnema sp. and Labeonema synodontisi. Based on molecular phylogenetic analyses and some morphological similarities, our findings support the hypothesis that Schrankiana is a member of the family Cosmocercidae, not Atractidae. Additionally, we provide the first ultrastructural descriptions of S. formosula, and establish the species' phylogenetic position from the Cosmocercidae.
The optimal management of a patent ductus arteriosus in a population of preterm infants is controversial. Traditionally, when the patent ductus arteriosus does not close either with conservative treatment or in response to pharmacological therapy, the only option is surgical closure. However, transcatheter occlusion might provide a therapeutic alternative.
Methods:
We searched PubMed, Embase, and Cochrane databases for non-randomised and randomised controlled trials that compared transcatheter percutaneous closure of patent ductus arteriosus with surgical ligation in low-birth-weight preterm infants (<2,500 g). A random-effects model was used for outcomes with high heterogeneity.
Results:
We included twelve studies comprising 4,668 low-birth-weight preterm infants, of whom 966 (20.7%) were in the transcatheter percutaneous closure group, and 3,702 (79.3%) patients were included in the surgical group. All-cause mortality (OR 0.28; 95% confidence interval 0.18–0.423; p < 0.00001; I2 = 0%) and haemodynamic instability (OR 0.10; 95% confidence interval 0.05–0.21; p < 0.001; I2 = 14%) were significantly lower in the transcatheter percutaneous closure group. There was no significant difference between transcatheter and surgical patent ductus arteriosus closure for the outcomes of bronchopulmonary dysplasia (0.93; 95% confidence interval 0.46–1.87; p = 0.83; I2 = 0%) and major complications (OR 0.76; 95% confidence interval 0.34–1.69; p = 0.51; I2 = 43%).
Conclusion:
These findings suggest that transcatheter patent ductus arteriosus closure in preterm infants under 2,500 g is a safe and effective alternative to surgical treatment. There was a substantial reduction in all-cause mortality and haemodynamic instability with transcatheter intervention compared to surgical closure.
What are human rights? What makes a particular human rights claim ‘genuine’ or ‘valid’? These are difficult questions with which current philosophical literature on human rights is concerned. They are also the same kind of questions that legal philosophers asked about Law throughout the 20th century. Drawing from the similarities between the two fields, I attempt to do with the concept of human rights something similar to what Ronald Dworkin accomplished with that of Law in Law’s Empire. First, I offer a critique of the two dominant perspectives on human rights—the Orthodox and Political views—that is similar in character to Dworkin’s Semantic Sting objection to Legal Positivism. Second, I sketch an alternative, Dworkinian-inspired framework that seeks to develop the notion of human rights as an interpretive concept. According to this framework, different accounts of human rights are to be understood as expressing different interpretations of the point (or purpose) of human rights practice.
Bilingualism has been shown to contribute to increased resilience against cognitive aging. One of the key brain structures linked to memory and dementia symptom onset, the hippocampus, has been observed to adapt in response to bilingual experience – at least in healthy individuals. However, in the context of neurodegenerative pathology, it is yet unclear what role previous bilingual experience might have in terms of sustaining integrity of this structure or related behavioral correlates. The present study adds to the limited cohort of research on the effects of bilingualism on neurocognitive outcomes in Mild Cognitive Impairment (MCI) using structural brain data. We investigate whether bilingual language experience (operationalized as language entropy) results in graded neurocognitive adaptations within a cohort of bilinguals diagnosed with MCI. Results reveal a non-linear effect of bilingual language entropy on hippocampal volume, although they do not predict episodic memory performance, nor age of MCI diagnosis.
Cosmocercoides Wilkie, 1930 are gastrointestinal parasites commonly found in amphibians and reptiles, with 4 species reported from the Neotropical region. In the present study, a new species of Cosmocercoides, namely Cosmocercoides amapari n. sp. is described using integrated approaches such as light and scanning microscopy, and DNA sequencing of the mitochondrial cytochrome c oxidase subunit 1 gene. The specimens were collected from the large intestine of 3 species of hylid frogs in Amapá, Brazil. The new species can be distinguished from its congeners by morphological traits, including the pattern of caudal papillae, absence of the gubernaculum, 2 poorly sclerotized spicules, presence of lateral alae and somatic papillae along the body. In addition, our molecular analyses and phylogenetic reconstructions strongly support the status of the new taxon, which clustered poorly with a large clade of Cosmocerca spp. Cosmocercoides amapari n. sp. is the 29th species of the genus, the 5th from the Neotropical region, the third reported in Brazil, the second described from the Amazon region and the first belonging to the Neotropical region with molecular data.
Fifty years of deforestation in the Arc of Deforestation have put at risk species survival, ecosystem services and the stability of biogeochemical cycles in Amazonia, with global repercussions. In response, we need to understand the diversity, distribution and abundance of flagship species groups, such as primates, which can serve as umbrella species for broad biodiversity conservation strategies and help mitigate climate change. Here we identify the range, suitable habitat areas and population size of Vieira's titi monkey Plecturocebus vieirai and use it as an emblematic example to discuss biodiversity conservation and climate change mitigation in one of the largest deforestation frontiers. Our findings show that deforestation for agriculture and cattle-ranching expansion is the major threat to P. vieirai and is responsible for present (56%) and projected (14%) reductions in habitat area and population size. We also found that human-driven climate change affects the P. vieirai niche negatively, triggering habitat degradation and further population decline even inside protected areas. Primate watching can be a profitable alternative to forest exploitation on private, public or Indigenous lands in the Arc of Deforestation and is a way to shift the traditional, predatory extraction of natural resources from Amazonia towards sustainable land use based on biodiversity conservation at local, regional and global scales, local people's welfare and climate change mitigation. New models of land use and income generation are required to protect the unique natural and human heritages of the Arc of Deforestation and the life-supporting ecosystem services and products provided by Amazonia.
The jaguar Panthera onca has lost 85% of its habitat in the Atlantic Forest, where it persists in small and isolated populations in the largest fragments. In the absence of recent records, the jaguar had previously been presumed extinct in the large Atlantic Forest fragments of the Serra do Mar in southern Brazil. However, as this region is mountainous, densely forested and difficult to access, the jaguar could still be present, but undetected. We carried out an intensive survey using camera traps and interviews with local people in a large (c. 6,500 km2) forest block. During 2011–2019, 98 camera-trap stations were established (14,239 trap-days), and 249 interviews were conducted in 102 grid cells of 5 × 5 km. We obtained the first images of the jaguar in the region, from which five individuals were identified, and interviewees provided records of the jaguar in 24 grid cells. Our findings increase the range of this species in the Atlantic Forest by 9%, and we recommend that the area should be classified as a jaguar conservation unit. As the area we surveyed is adjacent to the Serra do Mar jaguar conservation unit, the combined area of 19,262 km2 is the largest priority area for jaguar conservation in the Atlantic Forest. This proposed jaguar conservation unit could serve as a vital source of jaguar individuals for the coastal forests further south. We recommend that surveys are extended southwards to Santa Catarina state to determine whether the presumed extinction of jaguars in this state is another case of a false absence.
We present a metric condition $\TTMetric$ which describes the geometry of classical small cancellation groups and applies also to other known classes of groups such as two-dimensional Artin groups. We prove that presentations satisfying condition $\TTMetric$ are diagrammatically reducible in the sense of Sieradski and Gersten. In particular, we deduce that the standard presentation of an Artin group is aspherical if and only if it is diagrammatically reducible. We show that, under some extra hypotheses, $\TTMetric$-groups have quadratic Dehn functions and solvable conjugacy problem. In the spirit of Greendlinger's lemma, we prove that if a presentation P = 〈X| R〉 of group G satisfies conditions $\TTMetric -C'(\frac {1}{2})$, the length of any nontrivial word in the free group generated by X representing the trivial element in G is at least that of the shortest relator. We also introduce a strict metric condition $\TTMetricStrict$, which implies hyperbolicity.
This research communication presents an automatic method for the counting of somatic cells in buffalo milk, which includes the application of a fuzzy clustering method and image processing techniques (somatic cell count with fuzzy clustering and image processing|, SCCFCI). Somatic cell count (SCC) in milk is the main biomarker for assessing milk quality and it is traditionally performed by exhaustive methods consisting of the visual observation of cells in milk smears through a microscope, which generates uncertainties associated with human interpretation. Unlike other similar works, the proposed method applies the Fuzzy C-Means (FCM) method as a preprocessing step in order to separate the images (objects) of the cells into clusters according to the color intensity. This contributes signficantly to the performance of the subsequent processing steps (thresholding, segmentation and recognition/identification). Two methods of thresholding were evaluated and the Watershed Transform was used for the identification and separation of nearby cells. A detailed statistical analysis of the results showed that the SCCFCI method is able to provide results which are consistent with those obtained by conventional counting. This method therefore represents a viable alternative for quality control in buffalo milk production.
Climate change and heavy anthropic pressures are giving rise to important modifications in the rocky benthic communities of the Mediterranean Sea. In particular, sponge assemblages have been deeply affected due to the susceptibility of some species to dramatic phenomena such as mass mortalities or widespread variations in the abundance of other species. For this reason, long-term biodiversity monitoring of the sponge assemblages is important for understanding the direction of changes over time. We studied the sponge fauna living off Tricase Porto (Otranto Strait) and compared its composition with the results of a study conducted in the same area 50 years ago. The comparison indicated that the sponge diversity of this area has strongly increased in the last 50 years and a large number of the sponges recorded in the old survey are still present in the recent community. This evidence matches with other results obtained from different localities of the Mediterranean Sea indicating an increase of sponge diversity, possibly due to the present water warming. The description of two new Demosponge species, Diplastrella boeroi sp. nov. and Spirastrella angulata sp. nov., is also provided.