Examinando por Autor "Aguilar, E."
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Ítem Assessing cross-species transmission of hemoplasmas at the wild-domestic felid interface in Chile using genetic and landscape variables analysis(Nature Publishing Group, 2019-12) Sacristán, I.; Acuña, F.; Aguilar, E.; García, S.; López, M. J.; Cevidanes, A.; Cabello, J.; Hidalgo-Hermoso, E.; Johnson, W. E.; Poulin, E.; Millán, J.; Napolitano, C.The co-occurrence of domestic cats (Felis silvestris catus) and wild felids in rural landscapes can facilitate pathogen transmission. However, in the relatively-isolated regions of southern South America there have been no comprehensive studies to assess disease transmission risks between domestic cats and forest-dwelling wild felids such as guigna (Leopardus guigna). We evaluated hemoplasma infection and the possibility of transmission between domestic cats and guignas by comparing spatial and phylogenetic patterns of pathogen prevalence. Blood/spleen samples were collected from 102 wild guignas and 262 co-occurring rural domestic cats across the entire distribution range of guigna in Chile. Hemoplasma infection was assessed by direct sequencing of the 16S RNA gene. Infection with hemoplasmas was common and geographically widespread across different bioclimatic areas for both species. The most common feline Mycoplasma species in guigna and domestic cats were Candidatus M. haemominutum (CMhm) (15.7% guigna; 10.3% domestic cat) and Mycoplasma haemofelis (Mhf) (9.8% guigna, 6.1% domestic cat). A previously undescribed Mycoplasma sp. sequence was found in two guignas and one cat. Continuous forest-landscapes were associated with higher hemoplasma-prevalence in guignas. Shared hemoplasma nucleotide sequence types between guigna and domestic cats were rare, suggesting that cross-species transmission between guignas and domestic cats may occur, but is probably uncommon. Ectoparasites, which have been linked with hemoplasma transmission, were not found on guignas and were infrequent on domestic cats. Our results suggest that transmission pathways vary among hemoplasma species and, contrary to our predictions, domestic cats did not appear to be the main driver of hemoplasma infection in guignas in these human-dominated landscapes. © 2019, The Author(s).Ítem Cfr(B), cfr(C), and a New cfr-Like Gene, cfr(E), in Clostridium difficile Strains Recovered across Latin America(AMACC, 2020) Stojković, V.; Ulate, M.; Hidalgo-Villeda, F.; Aguilar, E.; Monge-Cascante, C.; Pizarro-Guajardo, M.; Tsai, K.; Tzoc, E.; Camorlinga, M.; Paredes-Sabja, D.; Quesada-Gómez, C.; Fujimori, D.; Rodríguez, C.Cfr is a radical S-adenosyl-L-methionine (SAM) enzyme that confers cross-resistance to antibiotics targeting the 23S rRNA through hypermethylation of nucleotide A2503. Three cfr-like genes implicated in antibiotic resistance have been described, two of which, cfr(B) and cfr(C), have been sporadically detected in Clostridium difficile. However, the methylase activity of Cfr(C) has not been confirmed. We found cfr(B), cfr(C), and a cfr-like gene that shows only 51 to 58% protein sequence identity to Cfr and Cfr-like enzymes in clinical C. difficile isolates recovered across nearly a decade in Mexico, Honduras, Costa Rica, and Chile. This new resistance gene was termed cfr(E). In agreement with the anticipated function of the cfrlike genes detected, all isolates exhibited high MIC values for several ribosome-targeting antibiotics. In addition, in vitro assays confirmed that Cfr(C) and Cfr(E) methylate Escherichia coli and, to a lesser extent, C. difficile 23S rRNA fragments at the expected positions. The analyzed isolates do not have mutations in 23S rRNA genes or genes encoding the ribosomal proteins L3 and L4 and lack poxtA, optrA, and pleuromutilin resistance genes. Moreover, these cfr-like genes were found in Tn6218-like transposons or integrative and conjugative elements (ICE) that could facilitate their transfer. These results indicate selection of potentially mobile cfr-like genes in C. difficile from Latin America and provide the first assessment of the methylation activity of Cfr(C) and Cfr(E), which belong to a cluster of Cfr-like proteins that does not include the functionally characterized enzymes Cfr, Cfr(B), and Cfr(D).Ítem Contrasting human perceptions of and attitudes towards two threatened small carnivores, Lycalopex fulvipes and Leopardus guigna, in rural communities adjacent to protected areas in Chile(Wildlife Information Liaison Development Society, 2018-04) Sacristán, I.; Cevidanes, A.; Acuña, F.; Aguilar, E.; García, S.; López, M.J.; Millán, J.; Napolitano, C.The interaction between humans and small carnivores is a phenomenon especially frequent in rural fringes, as is the case of communities surrounding natural areas. In Chile, two species of threatened carnivores, the Darwin's Fox and the Guigna, have increased their contact with humans due to human-induced changes in their habitat. The objective of this study was to characterize the interactions of these species with humans by assessing human perceptions and attitudes toward them, and to assess livestock and poultry ownership and management practices in local communities to evaluate their possible roles in the phenomenon. We conducted semi-structured interviews in rural communities adjacent to natural protected areas of two different regions in southern Chile. We found that people have a more positive perception of Darwin's Foxes than Guignas, but both species are considered damaging due to poultry attacks. Livestock and poultry management was generally deficient. Improvements in animal management and education programs could lead to a significant decrease in negative interactions. © Sacristan et al. 2018.Ítem Cross-species transmission of retroviruses among domestic and wild felids in human-occupied landscapes in Chile(John Wiley and Sons Inc, 2021-04) Sacristán, I.; Acuña, F.; Aguilar, E.; García, S.; José López, M.; Cabello, J.; Hidalgo-Hermoso, E.; Sanderson, J.; Terio, K.A.; Barrs, V.; Beatty, J.; Johnson, W.E.; Millán, J.; Poulin, E.; Napolitano, C.Human transformation of natural habitats facilitates pathogen transmission between domestic and wild species. The guigna (Leopardus guigna), a small felid found in Chile, has experienced habitat loss and an increased probability of contact with domestic cats. Here, we describe the interspecific transmission of feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) between domestic cats and guignas and assess its correlation with human landscape perturbation. Blood and tissue samples from 102 free-ranging guignas and 262 domestic cats were collected and analyzed by PCR and sequencing. Guigna and domestic cat FeLV and FIV prevalence were very similar. Phylogenetic analysis showed guigna FeLV and FIV sequences are positioned within worldwide domestic cat virus clades with high nucleotide similarity. Guigna FeLV infection was significantly associated with fragmented landscapes with resident domestic cats. There was little evidence of clinical signs of disease in guignas. Our results contribute to the understanding of the implications of landscape perturbation and emerging diseases. © 2021 The Authors. Evolutionary Applications published by John Wiley & Sons Ltd.