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Bioindicator species are useful to monitor wildlife exposure to plastic pollution, and responses to plastic leakage and policy interventions. Here we explore the biomonitoring potential of different seabird and shorebirds species across six years of monitoring in Brazil. Using the necropsy stranding database of the Beach Monitoring Project of the Santos Basin (PMP-BS), we evaluated i) the frequency of birds-plastic interactions in Brazil; ii) whether plastic interactions have changed through time and in different coastal regions; and iii) potential bioindicators for monitoring the exposure of seabirds to plastic in the nearshore South Atlantic Ocean. We found 37 species that had ingested plastic, including ten new records, found that the rates of tube-nosed seabirds increased through time, and suggested two potential species. We discuss the potential for biomonitoring marine pollution in the South Atlantic Ocean using PMP-BS, providing a scheme for a better plastic pollution monitoring in Brazil., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Magellanic penguins (Spheniscus magellanicus) migrate to the continental shelf of southern-southeastern Brazil during austral winter. Stranded penguins are directed to rehabilitation centers, where they occasionally develop fungal diseases. Aspergillosis, a mycosis caused by Aspergillus spp., is one of the most important diseases of captive penguins, while Candida sp. has been detected in penguins undergoing rehabilitation. Nevertheless, their occurrence in the wild is poorly understood. This study surveyed the occurrence of mycoses in free-ranging Magellanic penguins wintering in southeastern Brazil. These penguins were either found dead or stranded alive and died during transport to a rehabilitation center. Overall, 61 fresh to moderate autolyzed carcasses were necropsied. Upon necropsy, three juvenile males (4.9%) presented mycotic-consistent gross lesions. Histopathology and panfungal PCRs confirmed the mycoses. Major microscopic findings were marked chronic necrotizing multifocal to coalescent pneumonia, airsacculitis, and esophageal/gastric serositis with two types of intralesional fungal structures: (a) septated acute-angled branching hyphae (n = 2) and (b) yeast structures (n = 1), both PAS- and Grocott-positive. Sequences identical to Aspergillus sp. were retrieved in two cases, while the third had sequences identical to Candida palmioleophila. This study describes two cases of aspergillosis and one of candidiasis in free-ranging Magellanic penguins, confirming the species' susceptibility in the wild. These mycoses could be associated with the animals' poor body condition, and/or impaired immunity, and natural and anthropogenic challenges related to migration. To the authors' knowledge, this is the first report of aspergillosis in free-ranging Magellanic penguins in the Atlantic Ocean and of candidiasis in penguins worldwide.

Patients in the chronic phase of Chagas' disease suffer from a slowly evolving inflammatory cardiomyopathy that can lead to severe cardiac dilatation, congestive heart failure, and death. This process appears to be caused by autoimmune recognition of heart tissue by a mononuclear cell infiltrate decades after infection with the parasite Trypanosoma cruzi. Recent evidence suggests that there are circulating antibodies in chronic chagasic patients that alter the physiological behavior of the heart on binding to G-protein-coupled cardiovascular receptors, including beta1-adrenergic and m2 muscarinic receptors. A 42 kDa fusion protein was constructed that contains the central part of the third intracellular loop (i3; Arg(267)-Arg(381)) of the human m2 muscarinic receptor, linked to glutathione S-transferase. This fusion protein was overexpressed in Escherichia coli and subsequently purified by affinity chromatography. Based on Western blots, the i3 loop is specifically recognized by the sera of chronic chagasic patients who have reached advanced stages of cardiac failure (according to the Los Andes classification). Analysis of the prevalence and distribution of these antibodies shows a strong association between seropositive patients and moderate (group II) to severe (group III) heart dysfunction.

Antibodies of chronic chagasic patients have been shown to interfere with electric and mechanical activities of cardiac embryonic myocytes in culture and with whole mammalian hearts. A mechanism proposed for this effect involves interaction of the antibodies with G-protein-linked membrane receptors, thus leading to activation of beta adrenergic and muscarinic receptors; more specifically, IgG of chagasic patients would interact with the negatively charged regions of the second extracellular loop of these receptors. We performed competition experiments to test this hypothesis. We evaluated the effect of sera/IgG from patients previously known to depress electrogenesis and/or atrioventricular conduction in isolated rabbit hearts after incubation with live and lysed parasites, the peptide corresponding to the second extracellular loop (O2) of the M2 receptor, and different peptides derived from two ribosomal proteins of T. cruzi: P0 and P2beta. Our results indicate that 1) the antigenic factor inducing the functionally active IgGs in the chagasic patients is probably an intracellular T. cruzi antigen; 2) IgG/serum is interacting with the O2 region of the M2 receptor in the rabbit heart; and 3) the negative charges present in the ribosomal proteins of T. cruzi are important in mediating the interaction between the patients' serum/IgG and the receptor.