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1.
Mol Ecol ; : e17458, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970414

RESUMO

Colour signals play pivotal roles in different communication systems, and the evolution of these characters has been associated with behavioural ecology, integumentary production processes and perceptual mechanisms of the species involved. Here, we present the first insight into the molecular and histological basis of skin colour polymorphism within a miniaturized species of pumpkin toadlet, potentially representing the lowest size threshold for colour polytypism in tetrapods. Brachycephalus actaeus exhibits a coloration ranging from cryptic green to conspicuous orange skin, and our findings suggest that colour morphs differ in their capability to be detected by potential predators. We also found that the distribution and abundance of chromatophores are variable in the different colour morphs. The expression pattern of coloration related genes was predominantly associated with melanin synthesis (including dct, edn1, mlana, oca2, pmel, slc24a5, tyrp1 and wnt9a). Up-regulation of melanin genes in grey, green and brown skin was associated with higher melanophore abundance than in orange skin, where xanthophores predominate. Our findings provide a significant foundation for comparing and understanding the diverse pathways that contribute to the evolution of pigment production in the skin of amphibians.

2.
Proc Biol Sci ; 290(2011): 20232223, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37964521

RESUMO

The gut microbiome composition of terrestrial vertebrates is known to converge in response to common specialized dietary strategies, like leaf-eating (folivory) or ant- and termite-eating (myrmecophagy). To date, such convergence has been studied in mammals and birds, but has been neglected in amphibians. Here, we analysed 15 anuran species (frogs and toads) representing five Neotropical families and demonstrated the compositional convergence of the gut microbiomes of distantly related myrmecophagous species. Specifically, we found that the gut microbial communities of bufonids and microhylids, which have independently evolved myrmecophagy, were significantly more similar than expected based on their hosts' evolutionary divergence. Conversely, we found that gut microbiome composition was significantly associated with host evolutionary history in some cases. For instance, the microbiome composition of Xenohyla truncata, one of the few known amphibians that eat fruits, was not different from those of closely related tree frogs with an arthropod generalist diet. Bacterial taxa overrepresented in myrmecophagous species relative to other host families include Paludibacter, Treponema, and Rikenellaceae, suggesting diet-mediated selection and prey-to-predator transmission likely driving the observed compositional convergence. This study provides a basis for examining the roles of the gut microbiome in host tolerance and sequestration of toxic alkaloids from ants and termites.


Assuntos
Microbioma Gastrointestinal , Microbiota , Humanos , Animais , Evolução Biológica , Mamíferos/microbiologia , Anuros , RNA Ribossômico 16S
3.
Rev Bras Ginecol Obstet ; 43(10): 759-764, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34784632

RESUMO

OBJECTIVE: Breast surgery is considered a clean surgery; however, the rates of infection range between 3 and 15%. The objective of the present study was to intraoperatively investigate the presence of autochthonous microbiota in the breast. METHODS: Pieces of breast tissue collected from 49 patients who underwent elective breast surgery (reconstructive, diagnostic, or oncologic) were cultured. The pieces of breast tissue were approximately 1 cm in diameter and were removed from the retroareolar area, medial quadrant, and lateral quadrant. Each piece of tissue was incubated in brain heart infusion (BHI) broth for 7 days at 37°C, and in cases in which the medium became turbid due to microorganism growth, the samples were placed in Petri dishes for culturing and isolating strains and for identifying species using an automated counter. RESULTS: Microorganism growth was observed in the samples of 10 of the 49 patients (20.4%) and in 11 of the 218 pieces of tissue (5%). The detected species were Staphylococcus lugdunensis, Staphylococcus hominis, Staphylococcus epidermidis, Sphingomonas paucimobilis, and Aeromonas salmonicida. No patient with positive samples had clinical infection postoperatively. CONCLUSION: The presence of these bacteria in breast tissue in approximately 20% of the patients in this series suggests that breast surgery should be considered a potential source of contamination that may have implications for adverse reactions to breast implants and should be studied in the near future for their oncological implications in breast implant-associated large-cell lymphoma etiology.


OBJETIVO: A cirurgia de mama é considerada uma cirurgia limpa; entretanto, as taxas de infecção variam entre 3 e 15%. O objetivo deste estudo foi investigar no intraoperatório a presença de microbiota autóctone na mama. MéTODOS: : Pedaços de tecido mamário coletados de 49 pacientes submetidas à cirurgia eletiva da mama (reconstrutiva, diagnóstica ou oncológica) foram cultivados. Os pedaços de tecido mamário tinham aproximadamente 1 cm de diâmetro e foram removidos da área retroareolar e dos quadrantes medial e lateral. Cada pedaço de tecido foi incubado em caldo BHI (brain heart infusion) por 7 dias a 37 ° C, e nos casos em que o meio ficou turvo devido ao crescimento de microrganismos, as amostras foram colocadas em placas de Petri para cultivo e isolamento de cepas e para identificação de espécies usando um contador automatizado. RESULTADOS: O crescimento do microrganismo foi observado nas amostras de 10 das 49 pacientes (20,4%) e em 11 dos 218 pedaços de tecido (5%). As espécies detectadas foram Staphylococcus lugdunensis, Staphylococcus hominis, Staphylococcus epidermidis, Sphingomonas paucimobilis e Aeromonas salmonicida. Nenhum paciente com amostras positivas apresentou infecção clínica no pós-operatório. CONCLUSãO: : A presença dessas bactérias no tecido mamário em aproximadamente 20% das pacientes desta série sugere que a cirurgia mamária deve ser considerada uma fonte potencial de contaminação que pode ter implicações nas reações adversas aos implantes mamários e deve ser estudada em um futuro próximo por suas implicações oncológicas na etiologia do linfoma de células grandes associado ao implante de mama.


Assuntos
Implantes de Mama , Microbiota , Bactérias , Mama/cirurgia , Humanos
4.
Toxins (Basel) ; 13(11)2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34822600

RESUMO

The genus Brachycephalus is a fascinating group of miniaturized anurans from the Brazilian Atlantic Forest, comprising the conspicuous, brightly colored pumpkin-toadlets and the cryptic flea-toads. Pumpkin-toadlets are known to contain tetrodotoxins and therefore, their bright colors may perform an aposematic function. Previous studies based on a limited number of mitochondrial and nuclear-encoded markers supported the existence of two clades containing species of pumpkin-toadlet phenotype, but deep nodes remained largely unresolved or conflicting between data sets. We use new RNAseq data of 17 individuals from nine Brachycephalus species to infer their evolutionary relationships from a phylogenomic perspective. Analyses of almost 5300 nuclear-encoded ortholog protein-coding genes and full mitochondrial genomes confirmed the existence of two separate pumpkin-toadlet clades, suggesting the convergent evolution (or multiple reversals) of the bufoniform morphology, conspicuous coloration, and probably toxicity. In addition, the study of the mitochondrial gene order revealed that three species (B. hermogenesi, B. pitanga, and B. rotenbergae) display translocations of different tRNAs (NCY and CYA) from the WANCY tRNA cluster to a position between the genes ATP6 and COIII, showing a new mitochondrial gene order arrangement for vertebrates. The newly clarified phylogeny suggests that Brachycephalus has the potential to become a promising model taxon to understand the evolution of coloration, body plan and toxicity. Given that toxicity information is available for only few species of Brachycephalus, without data for any flea-toad species, we also emphasize the need for a wider screening of toxicity across species, together with more in-depth functional and ecological study of their phenotypes.


Assuntos
Anuros/fisiologia , Pigmentação da Pele/fisiologia , Transcriptoma , Animais , Anuros/genética , Brasil , Florestas , Genoma Mitocondrial , Fenótipo , Filogenia , Pigmentação da Pele/genética
5.
Rev. bras. ginecol. obstet ; 43(10): 759-764, Oct. 2021. tab
Artigo em Inglês | LILACS | ID: biblio-1357066

RESUMO

Abstract Objective: Breast surgery is considered a clean surgery; however, the rates of infection range between 3 and 15%. The objective of the present study was to intraoperatively investigate the presence of autochthonous microbiota in the breast. Methods: Pieces of breast tissue collected from 49 patients who underwent elective breast surgery (reconstructive, diagnostic, or oncologic) were cultured. The pieces of breast tissue were approximately 1 cm in diameter and were removed from the retroareolar area, medial quadrant, and lateral quadrant. Each piece of tissue was incubated in brain heart infusion (BHI) broth for 7 days at 37°C, and in cases in which the medium became turbid due to microorganism growth, the samples were placed in Petri dishes for culturing and isolating strains and for identifying species using an automated counter. Results: Microorganism growth was observed in the samples of 10 of the 49 patients (20.4%) and in 11 of the 218 pieces of tissue (5%). The detected species were Staphylococcus lugdunensis, Staphylococcus hominis, Staphylococcus epidermidis, Sphingomonas paucimobilis, and Aeromonas salmonicida. No patient with positive samples had clinical infection postoperatively. Conclusion: The presence of these bacteria in breast tissue in approximately 20% of the patients in this series suggests that breast surgery should be considered a potential source of contamination that may have implications for adverse reactions to breast implants and should be studied in the near future for their oncological implications in breast implant-associated large-cell lymphoma etiology.


Resumo Objetivo: A cirurgia de mama é considerada uma cirurgia limpa; entretanto, as taxas de infecção variam entre 3 e 15%. O objetivo deste estudo foi investigar no intraoperatório a presença de microbiota autóctone na mama. Métodos: Pedaços de tecido mamário coletados de 49 pacientes submetidas à cirurgia eletiva da mama (reconstrutiva, diagnóstica ou oncológica) foram cultivados. Os pedaços de tecido mamário tinham aproximadamente 1 cm de diâmetro e foram removidos da área retroareolar e dos quadrantes medial e lateral. Cada pedaço de tecido foi incubado em caldo BHI (brain heart infusion) por 7 dias a 37 ° C, e nos casos em que o meio ficou turvo devido ao crescimento de microrganismos, as amostras foram colocadas em placas de Petri para cultivo e isolamento de cepas e para identificação de espécies usando um contador automatizado. Resultados: O crescimento do microrganismo foi observado nas amostras de 10 das 49 pacientes (20,4%) e em 11 dos 218 pedaços de tecido (5%). As espécies detectadas foram Staphylococcus lugdunensis, Staphylococcus hominis, Staphylococcus epidermidis, Sphingomonas paucimobilis e Aeromonas salmonicida. Nenhum paciente com amostras positivas apresentou infecção clínica no pós-operatório. Conclusão: A presença dessas bactérias no tecido mamário em aproximadamente 20% das pacientes desta série sugere que a cirurgia mamária deve ser considerada uma fonte potencial de contaminação que pode ter implicações nas reações adversas aos implantes mamários e deve ser estudada em um futuro próximo por suas implicações oncológicas na etiologia do linfoma de células grandes associado ao implante de mama.


Assuntos
Humanos , Implantes de Mama , Microbiota , Bactérias , Mama/cirurgia
6.
Zootaxa ; 4415(1): 183-188, 2018 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-30313639

RESUMO

The advertisement calls are known for only eight species within the genus Brachycephalus. Herein, we describe the advertisement calls of B. olivaceus and B. quiririensis, both species from southern Atlantic Forest, state of Santa Catarina, Brazil. The advertisement calls of these species are similar, composed by one short and high-frequency note. The parameters range overlap between calls, as exemplified by the dominant frequency of 6.4-7.0 kHz in B. olivaceus and 6.2-6.5 kHz in B. quiririensis. Additionally, we provide a compilation of the available bioacoustic information for this genus.


Assuntos
Anuros , Animais , Brasil , Florestas , Vocalização Animal
7.
Zootaxa ; 4407(4): 483-505, 2018 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-29690168

RESUMO

We describe a new species of Brachycephalus from municipality of São Francisco do Sul and municipality of Itapoá, in the state of Santa Catarina, Brazil, southern Atlantic Forest. The new species is known from six localities from near sea level up to 250 meters and represents the first record of a "pumpkin-toadlet" occurring in the lowlands. Morphological traits and phylogenetic analysis of a fragment the 16S mtDNA gene place the new species in the Brachycephalus pernix group. The new species is supported by external morphology, osteology, advertisement call, and mtDNA divergence. It is characterized, among other traits by a dorsal body color dark green with a dark brown vertebral stripe, and an orange background; snout-vent length of 9.2-10.8 mm in males and 11.1-12.4 mm in females; and advertisement call short (0.02-0.03 seconds), composed of one high-frequency note (dominant frequency 6.6-7.3 kHz). We observed synchronized alternation in the emission of vocalizations among neighbor males, indicating that males of the new species are able to hear and use vocalizations to interact with each other. We provide descriptions of clutch, eggs, and juvenile and observations on parental care. The new species has not been recorded within any protected area and can be threatened by human-induced habitat loss and modification.


Assuntos
Anuros , Animais , Brasil , Feminino , Florestas , Masculino , Óvulo , Filogenia
8.
Zootaxa ; 4083(1): 40-56, 2016 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-27394218

RESUMO

We describe a new species of Brachycephalus that is morphologically similar to the flea-toads B. didactylus, B. hermogenesi, and B. pulex. The new species occurs from the sea level up to 1000 m and it is widely distributed throughout southern Atlantic Forest. Brachycephalus sulfuratus sp. nov. is distinguished from all of its congeners by the combination of the following characters: (1) small body size (SVL of adults: 7.4-8.5 mm for males and 9.0-10.8 mm for females); (2) "leptodactyliform" body; (3) pectoral girdle arciferal and less robust compared to the Brachycephalus species with "bufoniform" body; (4) procoracoid and epicoracoid fused with coracoid but separated from the clavicle by a large fenestrae; (5) toe I externally absent; toes II, III, IV, and V distinct; phalanges of toes II and V reduced; (6) skin smooth with no dermal ossifications; (7) in life, general background color brown with small dark-brown spots; skin of throat, chest, arms, and forearms with irregular yellow blotches; in ventral view, cloacal region of alive and preserved specimens surrounded by a dark-brown inverted v-shaped mark outlined with white; (8) advertisement call long, composed of a set of 4-7 high-frequency notes (6.2-7.2 kHz) repeated regularly.


Assuntos
Anuros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Anuros/genética , Anuros/crescimento & desenvolvimento , Anuros/fisiologia , Tamanho Corporal , Brasil , Feminino , Florestas , Masculino , Tamanho do Órgão , Filogenia , Vocalização Animal
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