Species baseline information is required for effective biodiversity conservation. Here we provide sound ecological data to support effective conservation of the Principe Scops-owl, Otus bikegila Melo, Freitas, Verbelen, Costa, Pereira, Fuchs, Sangster, Correia, de Lima & Crottini 2022, discovered in 2016. We mapped the observed and potential distribution, inferred habitat associations, estimated population size, and assessed the International Union for Conservation of Nature (IUCN) Red List category for this species. Surveys were carried out across Príncipe Island during the long and short dry seasons, recording owl presence in sampling points along transects. These data were used to model distribution, revealing that the Principe Scops-owl is restricted to 34.4 km2 in the south of the island, inside the Príncipe Obô Natural Park. Most records were in lower altitude native forest. Remoteness was the most important variable to explain presence at island level, followed by land use, which showed that the species is restricted to forest, clearly depending on native forest. Distance sampling using different models suggested a population density ranging between 33.4 individuals/km2 (95% CI: 23.6–47.2) and 46.4 individuals/km2 (95% CI: 29.3–73.6), which extrapolates to an estimated population size ranging from 1,149 individuals (95% CI: 813–1,623) to 1,597 individuals (95% CI: 1,007–2,533). We propose that the species is classified as “Critically Endangered” due to the small extent of occurrence, coupled with occurrence in a single location and inferred continuing declines in the extent of occurrence, area of occupancy, number of mature individuals and area, extent, and quality of habitat. Effective conservation of the Principe Scops-owl requires regular monitoring and further studies focusing on reproduction and potential nest predation by introduced mammals. Widespread support for the conservation of the Natural Park is vital to ensure the protection of this species and the endemic-rich native forests of Príncipe on which it depends.

The diagnosis of visceral leishmaniasis (VL) has improved with the search of novel antigens; however, their performance is limited when samples from VL/human immunodeficiency virus (HIV)-coinfected patients are tested. In this context, studies conducted to identify more suitable antigens to detect both VL and VL/HIC coinfection cases should be performed. In the current study, phage display was performed using serum samples from healthy subjects and VL, HIV-infected and VL/HIV-coinfected patients; aiming to identify novel phage-exposed epitopes to be evaluated with this diagnostic purpose. Nine non-repetitive and valid sequences were identified, synthetized and tested as peptides in enzyme-linked immunosorbent assay experiments. Results showed that three (Pep2, Pep3 and Pep4) peptides showed excellent performance to diagnose VL and VL/HIV coinfection, with 100% sensitivity and specificity values. The other peptides showed sensitivity varying from 50.9 to 80.0%, as well as specificity ranging from 60.0 to 95.6%. Pep2, Pep3 and Pep4 also showed a potential prognostic effect, since specific serological reactivity was significantly decreased after patient treatment. Bioinformatics assays indicated that Leishmania trypanothione reductase protein was predicted to contain these three conformational epitopes. In conclusion, data suggest that Pep2, Pep3 and Pep4 could be tested for the diagnosis of VL and VL/HIV coinfection.

The Adélie penguin (Pygoscelis adeliae) breeding population at Stranger Point, King George Island (25 de Mayo), increased in number from 1965/66 until 1980/81 after which it started to decrease almost continuously up to the present. A significant decrease in the number of breeding pairs and chicks crèched was observed between 1995/96 and 2013/14 (75% and 78%, respectively), although the rate of this decrease has slowed since 2006/07. Over the last seven years, larger interannual fluctuations were recorded in the number of breeding pairs and chicks in crèches, as well in the breeding success. The values for the index of breeding success during 2007/08, 2009/10 and 2012/13 were low and this parameter showed higher temporal fluctuation in the period 2007/08 to 2013/14. The reduction in breeding success and the number of chicks reared to crèche will unfavourably impact on future population size at Stranger Point through the reduction of new recruits. Although Adélie penguin population trends on the Antarctic Peninsula are linked to the marine environment variability (i.e. reduction in sea ice affecting the availability of prey), breeding success is also influenced by the amount of snow fall which has increased in recent years.

We previously observed that physalins have immunomodulatory properties, as well as antileishmanial and antiplasmodial activities. Here, we investigated the anti-Trypanosoma cruzi activity of physalins B, D, F and G. We found that physalins B and F were the most potent compounds against trypomastigote and epimastigote forms of T. cruzi. Electron microscopy of trypomastigotes incubated with physalin B showed disruption of kinetoplast, alterations in Golgi apparatus and endoplasmic reticulum, followed by the formation of myelin-like figures, which were stained with MDC to confirm their autophagic vacuole identity. Physalin B-mediated alteration in Golgi apparatus was likely due to T. cruzi protease perturbation; however physalins did not inhibit activity of the trypanosomal protease cruzain. Flow cytometry examination showed that cell death is mainly caused by necrosis. Treatment with physalins reduced the invasion process, as well as intracellular parasite development in macrophage cell culture, with a potency similar to benznidazole. We observed that a combination of physalins and benznidazole has a greater anti-T. cruzi activity than when compounds were used alone. These results indicate that physalins, specifically B and F, are potent and selective trypanocidal agents. They cause structural alterations and induce autophagy, which ultimately lead to parasite cell death by a necrotic process.

Transposons of the Mutator superfamily have been widely described in plants, but only recently have metazoan organisms been shown to harbour them. In this work we describe novel Mutator superfamily transposons from the genomes of the human parasites Schistosoma mansoni and S. japonicum, which we name Curupira-1 and Curupira-2. Curupira elements do not have Terminal Inverted Repeats (TIRs) at their extremities and generate Target Site Duplications (TSDs) of 9 base pairs. Curupira-2 transposons code for a conserved transposase and SWIM zinc finger domains, while Curupira-1 elements comprise these same domains plus a WRKY zinc finger. Alignment of transcript sequences from both elements back to the genomes indicates that they are subject to splicing to produce mature transcripts. Phylogenetic analyses indicate that these transposons represent a new lineage of metazoan Mutator-like elements with characteristics that are distinct from the recently described Phantom elements. Description of these novel schistosome transposons provides new insights in the evolution of transposable elements in schistosomes.