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1.
Microorganisms ; 11(6)2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37375033

RESUMEN

Plasmodium spp. and some other blood parasites belonging to the order Haemosporida are the focus of many epidemiological studies worldwide. However, haemosporidian parasites from wild animals are largely neglected in scientific research. For example, Polychromophilus parasites, which are exclusive to bats, are described in Europe, Asia, Africa, and Oceania, but little is known about their presence and genetic diversity in the New World. In this study, 224 samples of bats from remaining fragments of the Atlantic Forest and Pantanal biomes, as well as urbanized areas in southern and southeastern Brazil, were analyzed for the presence of haemosporidian parasites by PCR of the mitochondrial gene that encodes cytochrome b (cytb). The PCR fragments of the positive samples were sequenced and analyzed by the Bayesian inference method to reconstruct the phylogenetic relationships between Polychromophilus parasites from bats in Brazil and other countries. Sequences from Brazilian lineages of Polychromophilus were recovered in a clade with sequences from Polychromophilus murinus and close to the one Polychromophilus sequence obtained in Panama, the only available sequence for the American continent. This clade was restricted to bats of the family Vespertilionidae and distinct from Polychromophilus melanipherus, a parasite species mainly found in bats of the family Miniopteridae. The detection of Polychromophilus and the genetic proximity to P. murinus were further confirmed with the amplification of two other genes (clpc and asl). We also found a Haemosporida parasite sequence in a sample of Noctilio albiventris collected in the Pantanal biome, which presents phylogenetic proximity with avian Haemoproteus sequences. Morphological and molecular studies are still needed to conclude and describe the Polychromophilus species in Brazilian Myotis bats in more detail and to confirm Haemoproteus parasites in bats. Nevertheless, these molecular results in Brazilian bats confirm the importance of studying these neglected genera.

2.
Oecologia ; 202(2): 239-250, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37253787

RESUMEN

The general assumption that the survival patterns of tropical and southern temperate birds are similar lacks empirical data from higher latitudes. Regional comparisons of New World species are rare, and this assumption has been based on data from African studies. Here, we estimate the survival rates of 88 tropical and southern temperate bird populations (69 species) from eight localities in South America to evaluate the hypothesis that the survival of these populations is homogeneous at the regional scale. We estimated survival based on the Cormack-Jolly-Seber model and compared values from different environments. The survival estimates ranged from 0.30 to 0.80 (0.56 ± 0.12). Apparent survival did not differ significantly between low-latitude tropical environments (03°S) and the other sites from high-latitudes (between 22° and 34°S). Despite a predicted positive trend, body size was not significantly related to survival among passerines. On the other hand, phylogenetic relationships explained more than a third of the variation in bird survival. Based on the largest available database on South American bird species, our findings support the hypothesis that bird survival is homogeneous, at the regional scale, along the southern hemisphere. In particular, we reinforce the hypothesis that climatic variation has a limited influence on bird survival in the southern hemisphere.


Asunto(s)
Clima Tropical , Filogenia , América del Sur , Tamaño Corporal
3.
Braz J Microbiol ; 53(1): 63-70, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34787837

RESUMEN

INTRODUCTION: Several arboviruses causing human disease have been reported in Brazil. In nature, arboviruses maintain a lifecycle involving vertebrates and vectors, which may contribute for periodical reemergence of those of public health concern in tropical regions, as Mato Grosso State (MT). In this study, we searched for arboviruses in mosquito body pools sampled during the rainy season of 2018 in 21 bird watching points of Cuiabá and Varzea Grande, South Central MT. METHODS: In total, 2873 (57%) males and 2167 (43%) females belonging to six urban and sylvatic mosquito genera allocated to 398 pools were subjected to RNA extraction and RT-PCR for arboviruses. Positive pools were subjected to virus isolation in C6/36 cells. RESULTS: A total of 102/398 pools, 66/233 (29.6%) of females, and 36/165 (21.8%) of males, mostly sampled in May (31/102), were positive for arboviruses. Chikungunya virus (CHIKV) was distributed in 19 points, Zika virus (ZIKV) was found in 14 points, Mayaro virus (MAYV) in 10 points, and East Equine encephalitis virus (EEEV) in three points. Culex quinquefasciatus pools (39/89 of females and 24/99 of males) were positive for CHIKV, ZIKV, and MAYV; Aedes (Stg) aegypti pools (11/46 of females and 12/33 of males) for CHIKV, ZIKV, MAYV, and EEEV; Aedes albopictus female pools (8/29) for CHIKV, ZIKV, and EEEV; and Psorophora albigenu (2/12) and Psorophora ferox female pools (4/16) for CHIKV. CONCLUSIONS: Arbovirus molecular detection in mosquito populations varies considerable between geographical regions and epidemics, influenced by genetic characteristics and microbiome interference on virus replication. Although infected females are responsible for the transmission to vertebrates during bloodfeeding, male infection by CHIKV, ZIKV, and MAYV resultant from vertical route could lead to interepidemic maintenance of these arboviruses in their natural reservoirs.


Asunto(s)
Aedes , Fiebre Chikungunya , Virus Chikungunya , Encefalomielitis Equina , Infección por el Virus Zika , Virus Zika , Animales , Brasil/epidemiología , Fiebre Chikungunya/epidemiología , Virus Chikungunya/genética , Femenino , Humanos , Masculino , Mosquitos Vectores , Estaciones del Año , Virus Zika/genética
4.
An Acad Bras Cienc ; 93(2): e20201604, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33852672

RESUMEN

The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes.


Asunto(s)
Biodiversidad , Ecosistema , Brasil , Conservación de los Recursos Naturales , Humanos , Conocimiento
5.
Braz J Microbiol ; 50(2): 547-556, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30877663

RESUMEN

Coronaviruses are single-stranded positive-sense RNA viruses associated with important avian diseases. Their relatively high rates of mutation and recombination frequencies allow them to adapt to new hosts and ecological niches. Although Brazil has 18% of global avian species diversity, studies regarding the presence of avian viral diseases in wild birds in South America are scarce. In this study, we performed a retrospective analysis of the presence of CoVs in 746 wild birds. Oropharyngeal and cloacal swabs were obtained and placed together in vials containing VTM transport medium collected in different regions of Brazil between 2006 and 2013. Screening for viral nucleic acid was performed using conventional RT-PCR and pancoronavirus nested PCR. Positive samples were characterized by partial sequencing of the RNA-dependent RNA polymerase (RdRp) gene, and ensuing phylogenetic analysis was performed to investigate the association between virus epidemiology and bird migration routes. Coronavirus RNA were detected and sequenced from six samples, in which three were related to gammacoronaviruses group and the other three to deltacoronavirus group. Our study documents the presence of CoVs related to avian gamma- and deltacoronaviruses circulating in both urban- and poultry-farm regions of Brazil, implicating wild birds as potential carriers of CoVs which may represent a risk to poultry farms and public health in Brazil.


Asunto(s)
Enfermedades de las Aves/epidemiología , Aves/virología , Infecciones por Coronavirus/epidemiología , Coronavirus/aislamiento & purificación , Reservorios de Enfermedades/virología , Gammacoronavirus/aislamiento & purificación , Animales , Animales Salvajes/virología , Secuencia de Bases , Enfermedades de las Aves/virología , Brasil/epidemiología , Coronavirus/genética , Gammacoronavirus/genética , Filogenia , ARN Viral/genética , ARN Polimerasa Dependiente del ARN/genética , Estudios Retrospectivos
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