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1.
Mar Pollut Bull ; 203: 116407, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38701605

RESUMO

Cagarras Islands Archipelago, a no-take MPA in Southeast Brazil, was designated as Natural Monument (MONA Cagarras) and, more recently, recognized as Hope Spot for biodiversity conservation. This study aimed to assess plastic contamination by analyzing marine litter and microplastics in MONA Cagarras and surrounding waters. Marine litter (34.12 kg) was caught by artisanal fishermen in MONA Cagarras proximities, and plastics represented ∼79 %. Personal hygiene items and strains of hair were found, suggesting sewage-derived contamination from Ipanema SSO. Microplastics were detected in MONA Cagarras surface waters. Fragments and black particle were the most frequently found microplastic shape and color, respectively. µ-FTIR analysis identified, in descending order of occurrence, polystyrene-PS, polyethylene-PE, polyvinyl chloride-PVC, polypropylene-P, and polyamide-PA. Our integrated results of macro and microplastic contamination highlight an issue of effective conservation and health of marine biodiversity in MONA Cagarras and surrounding waters and a concern for better management of Brazilian MPAs.

2.
Plants (Basel) ; 12(12)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37375888

RESUMO

Asian soybean rust (ASR), caused by Phakopsora pachyrhizi, is one of the most serious soybean (Glycine max) diseases in tropical and subtropical regions. To facilitate the development of resistant varieties using gene pyramiding, DNA markers closely linked to seven resistance genes, namely, Rpp1, Rpp1-b, Rpp2, Rpp3, Rpp4, Rpp5, and Rpp6, were identified. Linkage analysis of resistance-related traits and marker genotypes using 13 segregating populations of ASR resistance, including eight previously published by our group and five newly developed populations, identified the resistance loci with markers at intervals of less than 2.0 cM for all seven resistance genes. Inoculation was conducted of the same population with two P. pachyrhizi isolates of different virulence, and two resistant varieties, 'Kinoshita' and 'Shiranui,' previously thought to only harbor Rpp5, was found to also harbor Rpp3. Markers closely linked to the resistance loci identified in this study will be used for ASR-resistance breeding and the identification of the genes responsible for resistance.

3.
An Acad Bras Cienc ; 95(2): e20201599, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37255126

RESUMO

We collected data during three consecutive breeding seasons (2015-2018) to assess the effects of Taphropiestes plaumanni (Coleoptera: Cavognathidae) on its bird hosts in a native forest of central eastern Argentina. We monitored bird nests for T. plaumanni in 207 nests of Masked Gnatcatcher (Polioptila dumicola, Polioptilidae), 302 nests of Vermilion Flycatcher (Pyrocephalus rubinus, Tyrannidae), 55 nests of Blue-and-yellow Tanager (Pipraeidea bonariensis, Thraupidae), 99 nests of Small-billed Elaenia (Elaenia parvirostris, Tyrannidae), 23 nests of Yellow-browed Tyrant (Satrapa icterophrys, Tyrannidae), and other passerine species nesting in the same forest patches. We found 13 nests in which nestlings showed evidences of parasitism of which four species are new hosts for this parasite (Vermilion Flycatcher, Masked Gnatcatcher, Red-crested Cardinal Paroaria coronata, Thraupidae, and Fork-tailed Flycatcher Tyrannus savana). Skin lesions caused by T. plaumanni larvae consisted in lacerations and crusts on the belly and chest areas. In one parasitized nest of Vermilion Flycatcher and one parasitized nest of Masked Gnatcatcher we observed the death of nestlings after being parasitized. This study adds new species to the list of hosts for this parasite, reports nestling skin lesions in nests with T. plaumanni parasitism, and reports for the first time the death of parasitized nestlings.


Assuntos
Besouros , Parasitos , Passeriformes , Animais , Comportamento de Nidação , Larva , Argentina
4.
Mar Pollut Bull ; 190: 114819, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36965266

RESUMO

Coastal and marine environments have been strongly influenced by anthropogenic activities, which may lead to high concentrations of different pollutants in sediments. Our study aimed to assess sediment contamination by polycyclic aromatic hydrocarbons (PAHs), phthalates (PAEs) and bisphenol A (BPA) in nine coastal and marine environments at Rio de Janeiro-Brazil. Physical and chemical water variables, grain-size parameters, moisture, and organic-matter content in sediments were assessed by sampling station. Multivariate analysis evidenced environmental differences between coastal lagoon and oceanic beaches, mostly influenced by marine waters. Differences among bay's beaches were mostly evidenced by sediment characteristics. PAHs and BPA were not detected in samples. For the first time, PAEs were found in sediments at Rio de Janeiro coast (South Atlantic). DEHP was detected in all coastal and marine environments, DBP was found in coastal lagoon and three marine environments. DnOP and DINP were solely found in the coastal lagoon.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Brasil , Oceanos e Mares , Hidrocarbonetos Policíclicos Aromáticos/análise
5.
Mol Ecol ; 32(9): 2186-2205, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36798996

RESUMO

Understanding the factors that govern variation in genetic structure across species is key to the study of speciation and population genetics. Genetic structure has been linked to several aspects of life history, such as foraging strategy, habitat association, migration distance, and dispersal ability, all of which might influence dispersal and gene flow. Comparative studies of population genetic data from species with differing life histories provide opportunities to tease apart the role of dispersal in shaping gene flow and population genetic structure. Here, we examine population genetic data from sets of bird species specialized on a series of Amazonian habitat types hypothesized to filter for species with dramatically different dispersal abilities: stable upland forest, dynamic floodplain forest, and highly dynamic riverine islands. Using genome-wide markers, we show that habitat type has a significant effect on population genetic structure, with species in upland forest, floodplain forest, and riverine islands exhibiting progressively lower levels of structure. Although morphological traits used as proxies for individual-level dispersal ability did not explain this pattern, population genetic measures of gene flow are elevated in species from more dynamic riverine habitats. Our results suggest that the habitat in which a species occurs drives the degree of population genetic structuring via its impact on long-term fluctuations in levels of gene flow, with species in highly dynamic habitats having particularly elevated gene flow. These differences in genetic variation across taxa specialized in distinct habitats may lead to disparate responses to environmental change or habitat-specific diversification dynamics over evolutionary time scales.


A compreensão dos fatores que governam a variação da estrutura genética entre as espécies é fundamental para o estudo da especiação e da genética das populações. A estrutura genética tem sido ligada a vários aspectos da história da vida, tais como estratégia de forrageio, associação ao habitat, distância de migração e capacidade de dispersão, os quais poderiam influenciar a dispersão e o fluxo gênico. Estudos comparativos usando espécies que diferem nas suas histórias de vida oferecem uma oportunidade para desvendar o papel da dispersão no estabelecimento do fluxo gênico e da estrutura genética da população. Aqui examinamos dados genéticos populacionais de diversas espécies de aves com diferentes capacidades de dispersão especializadas em três habitats amazônicos, incluindo florestas de terra-firme, florestas de várzea e ilhas fluviais, cujos ambientes ripários são altamente dinâmicos. Utilizando dados genômicos que incluem milhares de loci, mostramos que o tipo de habitat tem um efeito significativo na estruturação genética das populações; espécies de florestas de terra-firme, florestas de várzea e ilhas fluviais exibem níveis de estruturação progressivamente menores. Embora os traços morfológicos frequentemente usados como indicadores da capacidade de dispersão a nível individual não expliquem este padrão, as medidas genéticas populacionais de fluxo gênico são altas em espécies associadas a habitats ribeirinhos mais dinâmicos. Nossos resultados sugerem que o habitat no qual uma espécie é encontrada determina o grau de estruturação genética da população através de seu impacto nas flutuações de longo prazo do fluxo gênico, com espécies em habitats altamente dinâmicos tendo um fluxo gênico particularmente alto. As diferenças na variação genética dos táxons especializados em diferentes habitats podem resultar em respostas díspares às mesmas mudanças ambientais, ou dinâmicas de diversificação específicas a um determinado habitat ao longo de escalas de tempo evolutivas.


Comprender los factores que rigen la variación de la estructura genética entre especies es clave para el estudio de la especiación y la genética de poblaciones. La estructura genética se ha relacionado con varios aspectos de la historia vital, como la estrategia de búsqueda de alimento, la asociación de hábitats, la distancia de migración y la capacidad de dispersión, factores todos ellos que podrían influir en la dispersión y el flujo genético. Los estudios comparativos de datos genéticos poblacionales de especies con historias vitales diferentes ofrecen la oportunidad de desentrañar el papel de la dispersión en la conformación del flujo genético y la estructura genética poblacional. En este trabajo examinamos los datos genéticos de poblaciones de especies de aves especializadas en una serie de hábitats amazónicos que, según la hipótesis, filtran especies con capacidades de dispersión radicalmente diferentes: bosques estables de tierras altas, bosques dinámicos de llanuras aluviales e islas fluviales altamente dinámicas. Utilizando marcadores genómicos, demostramos que el tipo de hábitat tiene un efecto significativo en la estructura genética de la población, y que las especies de los bosques de tierras altas, los bosques inundables y las islas fluviales presentan niveles de estructura progresivamente más bajos. Aunque los rasgos morfológicos utilizados como indicadores de la capacidad de dispersión individual no explican este patrón, las medidas genéticas poblacionales del flujo genético son más elevadas en las especies de hábitats fluviales más dinámicos. Nuestros resultados sugieren que el hábitat en el que se encuentra una especie determina el grado de estructuración genética de la población a través de su impacto en las fluctuaciones a largo plazo de los niveles de flujo genético, siendo las especies de hábitats muy dinámicos las que presentan un flujo genético particularmente elevado. Estas diferencias en la variación genética entre taxones especializados en hábitats distintos pueden dar lugar a respuestas dispares al cambio ambiental o a dinámicas de diversificación específicas del hbitat a lo largo de escalas temporales evolutivas.


Assuntos
Ecossistema , Fluxo Gênico , Animais , Florestas , Aves/genética , Genética Populacional , Variação Genética
6.
Int J Cardiovasc Imaging ; 39(1): 77-85, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36515755

RESUMO

The Coronavirus Disease 2019 (COVID-19) pandemic has transformed health systems worldwide. There is conflicting data regarding the degree of cardiovascular involvement following infection. A registry was designed to evaluate the prevalence of echocardiographic abnormalities in adults recovered from COVID-19. We prospectively evaluated 595 participants (mean age 45.5 ± 14.9 years; 50.8% female) from 10 institutions in Argentina and Brazil. Median time between infection and evaluation was two months, and 82.5% of participants were not hospitalized for their infection. Echocardiographic studies were conducted with General Electric equipment; 2DE imaging and global longitudinal strain (GLS) of both ventricles were performed. A total of 61.7% of the participants denied relevant cardiovascular history and 41.8% had prolonged symptoms after resolution of COVID-19 infection. Mean left ventricular ejection fraction (LVEF) was 61.0 ± 5.5% overall. In patients without prior comorbidities, 8.2% had some echocardiographic abnormality: 5.7% had reduced GLS, 3.0% had a LVEF below normal range, and 1.1% had wall motion abnormalities. The right ventricle (RV) was dilated in 1.6% of participants, 3.1% had a reduced GLS, and 0.27% had reduced RV function. Mild pericardial effusion was observed in 0.82% of participants. Male patients were more likely to have new echocardiographic abnormalities (OR 2.82, p = 0.002). Time elapsed since infection resolution (p = 0.245), presence of symptoms (p = 0.927), or history of hospitalization during infection (p = 0.671) did not have any correlation with echocardiographic abnormalities. Cardiovascular abnormalities after COVID-19 infection are rare and usually mild, especially following mild infection, being a low GLS of left and right ventricle, the most common ones in our registry. Post COVID cardiac abnormalities may be more frequent among males.


Assuntos
COVID-19 , Anormalidades Cardiovasculares , Adulto , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Função Ventricular Esquerda , Volume Sistólico , Estudos Retrospectivos , Valor Preditivo dos Testes , Ecocardiografia/métodos , Sistema de Registros
7.
Artigo em Inglês | MEDLINE | ID: mdl-38248509

RESUMO

Microplastic contamination is a global concern due to its conspicuous presence in aquatic ecosystems and its toxic nature to environmental and human health. False mussels are among the most notable fresh- and brackish water invaders. The invasive Mytilopsis leucophaeata in Rodrigo de Freitas Lagoon-RFL (Rio de Janeiro, Brazil) is the most abundant macrofaunal invertebrate, widely established and distributed throughout the lagoon. This study aimed to assess microplastic contamination in this invasive filter feeder and evaluate its potential use as a bioindicator. Agglomerates (~100 mussels) were manually collected using a stainless-steel spatula in ten sampling areas distributed throughout the whole lagoon and kept frozen. In the laboratory, 60 individuals were sorted by area for soft-tissue digestion. Each pool of 10 soft-tissue mussels (n = 6 by area) was wet-weighted and then placed in a 150-mL decontaminated glass beaker with 50 mL of 10% KOH. Samples were heated (40 °C) for 48 h, and digested samples were filtered in glass-fiber membranes. Microplastics were found in all samples of mussels (n = 60) from RFL; the particles were mostly lower than 100 µm with a mean concentration (±SD) of 35.96 ± 47.64 MPs g wet-weight-1. Microplastics were distinguished in seven shapes with different occurrences in samples (%): fiber (43.3%); fragment (34.3%); film (16.3%); sponge/foam (4.9%); pellet (0.57%), rope/filaments (0.17%); and undefined (0.4%). Thirteen colors of microplastics were found, but transparent (54.94%), black (10.77%), and white (9.36%) were the most common. Mytilopsis leucophaeata were useful to assess microplastic contamination in RFL and might be preferentially used in other invaded brackish systems instead of native and often threatened bivalves. Our results confirm the effective application of bivalves as an indicator of coastal microplastic pollution.


Assuntos
Bivalves , Microplásticos , Humanos , Animais , Plásticos , Ecossistema , Brasil
8.
Food Res Int ; 162(Pt A): 111984, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461227

RESUMO

The generation albumin-based nanocarriers by precipitation from solution has great interest in the formulation of advanced nutritional products. Microfluidic techniques enable the implementation of low energy and continuum processes, with fast mass transfer and homogeneous mixing at the microscale. Here we describe the microfluidic generation of curcumin-loaded alpha lactalbumin nanoparticles in a simple and inexpensive way, by using off-the-shelf devices designed to produce solvent-shifting nanoprecipitation in core-sheath flows driven by gravity, which has not been reported before. Nanoparticles were characterized by dynamic light scattering, electron microscopy, and infrared spectroscopy. The microfluidic operating conditions were defined by theory and experiments, and the critical parameters controlling the nanoparticles diameter were identified. The prepared nanoparticles resulted practically monodisperse, the curcumin entrapment efficiency was about 40 %, and almost 70 % of the bioactive was gradually delivered in release experiments. The proposed methodology is a promising route to scale up the microfluidic elaboration of nanoparticles for the entrapment of active ingredients.


Assuntos
Curcumina , Nanopartículas , Microfluídica , Albuminas , Lactalbumina
9.
Mar Pollut Bull ; 181: 113865, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35759900

RESUMO

Total and partial restrictions to beach access during COVID-19 pandemic created an opportunity to evaluate its effect on coastal pollution. We aimed to determine the impact of access restrictions on solid waste pollution at Copacabana beach, Brazil. Solid waste amount was analyzed considering beach access restrictions: unrestricted, total closure, partial restriction, new normal. Relationships of atmospheric temperature and precipitation with access restrictions were assessed and confounding effects controlled for further analyses. Beach access restrictions significantly reduced solid waste pollution at Copacabana beach, beach closure reduced waste amount in 72 %. Partial restrictions and new normal periods have significantly reduced solid wastes amount on the beach in 60 % and 36.88 %, respectively. Qualitative data revealed that most of solid wastes were single-use plastics recently disposed at Copacabana beach, reflecting beachgoer's effects on waste left on the beach. A positive impact of COVID-19 pandemic restrictions was detected on solid waste pollution at Copacabana beach.


Assuntos
Praias , COVID-19 , Brasil , COVID-19/epidemiologia , Monitoramento Ambiental , Humanos , Pandemias , Plásticos , Resíduos Sólidos , Resíduos/análise
10.
J Comput Chem ; 43(22): 1484-1494, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35731622

RESUMO

In the present study, the differential scattering cross-sections, depolarization ratios and Raman shifts of small molecular systems are obtained from configuration iteration wave functions of vibrational self-consistent field (VSCF) states. The transition polarizabilities were modeled using the Placzek approximation, neglecting those contributions not arising from the electric dipole mechanism. This theoretical approach is considered a good approximation for samples that absorb in the UV range if the excitation radiation falls in the visible region, as is the case of the molecules selected for the present study, namely: water, methane, and acetylene. Potential energy and electronic polarizability surfaces are calculated by the CCSD(T) and CC3 methods with aug-cc-p(C)V(T,Q,5)Z basis sets. The vibrational Hamiltonian includes the vibrational angular momentum contribution of the Watson kinetic energy operator. As expected, due to the variational nature of the VSCF and vibrational configuration interaction (VCI) methods, the Raman transition wavenumbers are substantially improved over the harmonic predictions. Surprisingly, the scattering cross-sections obtained using the harmonic approximation or the VSCF method better agrees with the experimental values than those cross-sections predicted using VCI wave functions. The more significant deviations of the VCI results from the experimental reference may be related to the significant uncertainties of the measured cross-sections. Still, it may also indicate that the VCI Raman transition moments may require a more accurate description of the electronic polarizability surface. Finally, the depolarization ratios calculated for H2 O and C2 D2 using harmonic and VCI wave functions have similar accuracy, whereas, for C2 H2 and C2 HD, the VCI results are more accurate.


Assuntos
Teoria Quântica , Análise Espectral Raman , Vibração , Água
11.
Integr Zool ; 17(3): 408-419, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33876575

RESUMO

Nestling growth parameters are integral components of avian life-history strategies as they are crucial determinants of individual survival. Although many factors impact on nestling growth, the relative contribution of each one is still debated in the literature. Most studies rely on the assumption that each factor directly affects nestling growth, but indirect effects mediated by other factors are usually the rule in nature. In this study, we present a comprehensive view of both direct and indirect factors affecting nestling growth using the Red-crested Cardinal (Paroaria coronata) as model system. We evaluated the relative importance of different habitat (forest structure), biotic interactions (botfly larvae ectoparasitism, number of siblings, hatching order), and temporal factors (time of breeding) on nestling growth parameters in 278 nestlings of 128 nests by using piecewise structural equation models. We found that botfly ectoparasitism had the strongest direct effect on nestling growth and, in turn, forest structure increased the probability of botfly occurrence. Besides, the interaction between the number of siblings and hatching order influenced nestling growth, indicating that the first and second nestlings had disproportionately higher growth rates in large than in small clutches. Time of breeding also showed a strong positive indirect effect on botfly occurrence, as well as a weak direct positive effect on nestling growth. Our results demonstrate that, under natural conditions, nestling growth is driven by different factors acting not only directly, but also indirectly on this essential life history trait, and that these factors weave a complex web of interrelated variables.


Assuntos
Passeriformes , Animais , Ecossistema
12.
Artigo em Inglês | MEDLINE | ID: mdl-34909653

RESUMO

Fat burners are a category of nutritional supplements that are claimed to increase the metabolism and promote greater energy expenditure, leading to weight loss. However, little is known about the side effects on gastrointestinal motility. In this study, we evaluated the effect of ingestion with a fat burner named Thermbuterol® (THERM) on the gastric motility and food behavior of mice. THERM compounds were identified using nuclear magnetic resonance (NMR). Mice received variable doses of THERM (10, 50, 100 or 300 â€‹mg/kg, p.o.) or NaCl 0.15 â€‹M (control). Gastric emptying (GE) was assessed using the phenol red technique. Another set of mice was pretreated with intraperitoneal administration of hexamethonium (HEXA, 10 â€‹mg/kg), prazosin (PRAZ, 0.25 â€‹mg/kg), propranolol (PROP, 2 â€‹mg/kg), parachlorophenylalanine (PCPA, 300 â€‹mg/kg) or ondansetron (ONDA, 50 â€‹µg/kg) 30 â€‹min before THERM treatment for evaluation of GE. We assessed the gastrointestinal responsiveness in vitro as well as THERM's effects on food behavior. Caffeine was the major compound of THERM, identified by NMR. THERM 100 and 300 â€‹mg/kg decreased GE compared to the respective controls. Pretreatment with PRAZ or PROP did not prevent gastric dysmotility induced by THERM 100 â€‹mg/kg. However, the pretreatment with HEXA, ONDA or PCPA prevented GE delay induced by THERM. In vitro, THERM relaxed contractions in strips of longitudinal gastric fundus and duodenum. THERM also increased food intake, which was prevented by PCPA and ONDA treatments. THERM decreased GE of a liquid and increased food intake in mice, a phenomenon mediated by the autonomic nicotinic receptors and serotoninergic receptor.

13.
An Acad Bras Cienc ; 93(suppl 4): e20210520, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34852066

RESUMO

Fluctuation asymmetries (FA) are random on the bilateral symmetry plan of paired morphological characters, and other types of symmetry, such as: for instance, translational or rotational symmetry, in response to environmental, and genetic stress. The relationship of FA with gonadossomatic (GSI), hepatosomatic (HSI), and fullness (RI) indexes and condition factor (K) for juveniles (n=8), adults (n=32), males (n=9), and females (n=26) of Corocoro grunt Orthopristis ruber were evaluated in this paper. The composite fluctuating asymmetry (CFA) was used to calculate the combined effects of FA over these four organosomatic indexes of 66 Corocoro grunt caught during 2011 in Guanabara Bay, Brazil, one of the most eutrophic coastal bays in the world. Redundancy Analysis (RDA) confirmed a significant relationship between CFA and the physiological descriptors (HSI, RI, K), but without clear differences among juveniles, adults, and sexes. Our results support the potential of CFA to be used as a proxy of environmental effects over reef-associated fish species in a tropical bay, but the relationship between CFA and physiological descriptors is complex, and further studies, such as experimental trials, are needed.


Assuntos
Baías , Peixes , Animais , Brasil , Feminino , Masculino
14.
Front Vet Sci ; 8: 679049, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34708099

RESUMO

The illegal capture and trade of wild birds have long been threats to biodiversity. The rehabilitation and release of confiscated animals may be a useful conservation tool in species management. However, differences between populations regarding health (e.g., different pathogens) and adaptation (e.g., local adaptation) must be taken into account, since both can negatively impact the recipient population. In this pilot study, we used two of the most illegally trafficked Brazilian wild passerine species, namely the red-crested cardinal (Paroaria coronata) and green-winged saltator (Saltator similis) as case studies and assessed some of the health threats that the release of confiscated passerines may pose to free-living birds. We also investigated the level of difference in mitochondrial genetic structure among populations living in different ecoregions. Blood, feces, and oropharyngeal swabs from confiscated (n = 115) and free-living (n = 120) passerines from the release sites were tested for the Newcastle disease virus, Salmonella spp., and Mycoplasma gallisepticum. These are considered major avian diseases by the Brazilian National Avian Health Program. We analyzed mtDNA to study the difference in genetic structure between populations using samples from 127 free-living passerines. We found no evidence of the Newcastle disease virus or Salmonella spp. in confiscated or free-living passerines from either species. However, the levels of infection with M. galissepticum detected in our study for red-crested cardinals and green-winged saltators calls for a high degree of caution in captive release programs. The difference in genetic structure between populations occurring in different regions was low, and was not significant between those from the Pampa/Subtropical Grasslands region. These results suggest that it may be possible to establish a cost-effective and sensitive protocol for releasing confiscated songbirds, provided that further genome-wide studies indicate that the functional genetic diversity among (at least some of the) populations is also low.

15.
An Acad Bras Cienc ; 93(4): e20191221, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495199

RESUMO

The invasion record for the estuarine bivalve Mytilopsis leucophaeata in Brazil is in Rio de Janeiro city, including the Rodrigo de Freitas Lagoon, where high densities of this invader were registered. This work aimed to (1) assess the composition and structure of the benthic macrofauna associated with this invader in Rodrigo de Freitas Lagoon, (2) analyze the spatiotemporal variation of richness, density and diversity of the associated benthic community, and (3) correlate changes on the density of the associated benthic species with some water quality variables and the density of M. leucophaeata. Clusters of M. leucophaeata were collected monthly (two years) in four sites. Nine taxa associated with M. leucophaeata were found; Heleobia sp. (Gastropoda) and Melita mangrovi (Amphipoda) showed the highest densities. The structure of the benthic macrofauna slightly differed among sampling sites, but not between dry and wet seasons. The water quality parameters, specific patterns of each taxon and high densities of M. leucophaeata contribute to variations in density of the associated species. Oscillations in the densities of M. leucophaeata and the native bivalve Brachidontes darwinianus suggest some agonistic relationship between them, such as a competition for space.


Assuntos
Anfípodes , Bivalves , Animais , Brasil , Estações do Ano , Qualidade da Água
16.
Environ Sci Pollut Res Int ; 28(40): 55846-55868, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34480308

RESUMO

Besides human health risks, phycotoxins may cause physiological injuries on molluscan shellfish and, consequently, damages to marine ecosystems and global fisheries production. In this way, this review aimed to present an overview of HABs impacts on marine shellfish by evaluating the effects of cultivated molluscs exposure to microalgae and cyanobacteria that form blooms and/or synthesize toxins. More specifically, it was assessed the main molluscan shellfish responses to harmful algae, trophic transfer and dynamics of phycotoxins, and the risks for human health. Of the 2420 results obtained from literature search, 150 scientific publications were selected after thorough inspections for subject adherence. In total, 70 molluscan species and 37 taxa of harmful algae were assessed from retrieved scientific publications. A significant positive correlation was found between the marine production of molluscs and the number of available studies by molluscan category. Molluscan responses to HABs and phycotoxins were categorized and discussed in three sub-sections: effects on grazing and behavior, metabolic and physiological reactions, and fitness consequences. The main histopathological injuries and toxin concentrations in molluscan tissues were also compiled and discussed. Bivalves often accumulate more toxins than gastropods and cephalopods, occasionally exceeding recommended levels for safe consumption, representing a risk for human health. Harmful algae impact on molluscan shellfish are complex to trace and predict; however, considering the perspective of increase in the occurrence and intensity of HABs, the intensification of efforts to expand the knowledge about HABs impacts on marine molluscs is crucial to mitigate the damages on economy and human health.


Assuntos
Bivalves , Proliferação Nociva de Algas , Animais , Ecossistema , Humanos , Alimentos Marinhos , Frutos do Mar
17.
Mar Pollut Bull ; 169: 112508, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34049065

RESUMO

The present study aimed to assess corocoro grunt use as bioindicator of Hg contamination in coastal marine systems by testing environmental (seasons) and biological effects (sexual maturity, size and weight) on THg accumulation and assessing human health risk. Fish was captured in winter and summer seasons at Vermelha Beach, Rio de Janeiro, Southeast Brazil. Adult O. ruber showed significantly higher THg than juveniles, and THg concentrations were positively correlated to fish length and weight. Fish THg concentrations did not differ between seasons and were below the accepted limit for human consumption. Human exposure risk by fish consumption was 0.31 µg MeHg kg-1 week-1 and the hazard quotient was 0.44 (0.11-1.84). Our results confirm the applied use of O. ruber as sentinel species for Hg contamination monitoring and highlight concern for its consumption, especially for local fishermen populations that highly consume this fish and may be more susceptible to Hg adverse effects.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Poluentes Químicos da Água , Animais , Fatores Biológicos , Brasil , Monitoramento Ambiental , Peixes , Humanos , Mercúrio/análise , Medição de Risco , Espécies Sentinelas , Poluentes Químicos da Água/análise
18.
J Phys Chem A ; 125(15): 3219-3229, 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33847496

RESUMO

We present a complete theoretical protocol to partition infrared intensities into terms owing to individual atoms by two different but related approaches: the atomic contributions (ACs) show how the entire molecular vibrational motion affects the electronic structure of a single atom and the total infrared intensity. On the other hand, the dynamic contributions (DCs) show how the displacement of a single atom alters the electronic structure of the entire molecule and the total intensity. The two analyses are complementary ways of partitioning the same total intensity and conserve most of the features of the total intensity itself. Combined, they are called the AC/DC analysis. These can be further partitioned following the CCTDP (or CCT) models according to the population analysis chosen by the researcher. The main conceptual features of the equations are highlighted, and representative numerical results are shown to support the interpretation of the equations. The results are invariant to rotation and translation and can readily be extended to molecules of any size, shape, or symmetry. Although the AC/DC analysis requires the choice of a charge model, all charge models that correctly reproduce the total molecular dipole moment can be used. A fully automated protocol managed by the Placzek program is made available, free of charge and with input examples.

19.
Environ Pollut ; 268(Pt B): 115911, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33128931

RESUMO

BPA is chemical pollutant of very high concern due to its toxicity to the environment and risks for human health. Environmental concern consists in BPA entrance into aquatic ecosystems due to acute and chronic toxicity to invertebrates and vertebrates. This study aimed to determine acute BPA toxicity to tropical estuarine-marine species of four trophic levels and integrate BPA toxicity values using species sensitivity distribution (SSD) analysis. Our hypothesis is that BPA toxicity increases towards higher trophic levels. Microalga (Tetraselmis sp.), zooplanktonic grazer (Artemia salina), deposit-feeder invertebrate (Heleobia australis), and omnivorous fish (Poecilia vivipara) were chosen as experimental models. Tetraselmis sp. showed the highest BPA tolerance, without a concentration-dependent response. Species sensitivity have increased from A. salina (LC50,96h = 107.2 mg L-1), followed by H. australis (LC50,96h = 11.53.5 mg L-1), to P. vivipara (LC50,96h = 3.5 mg L-1). Despite the toxicity hierarchy towards trophic levels, which partially supported our hypothesis, SSD did not evidence a clear pattern among estuarine-marine trophic groups. Our study disclosed the sensitivity of not yet investigated species to BPA and, in an integrative way, highlighted BPA toxic effects at different trophic levels. Although estimated acute hazardous concentration (HC5 = 1.18 mg L-1) for estuarine and marine species was higher than environmentally relevant concentrations, sublethal adverse effects induced by BPA exposure may lead to unbalances in population levels and consequently affect the ecological functioning of tropical coastal systems.


Assuntos
Ecossistema , Poluentes Químicos da Água , Animais , Compostos Benzidrílicos/análise , Compostos Benzidrílicos/toxicidade , Humanos , Fenóis/análise , Fenóis/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
20.
Mol Ecol ; 29(22): 4457-4472, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32974981

RESUMO

South American dry forests have a complex and poorly understood biogeographic history. Based on the fragmented distribution of many Neotropical dry forest species, it has been suggested that this biome was more widely distributed and contiguous under drier climate conditions in the Pleistocene. To test this scenario, known as the Pleistocene Arc Hypothesis, we studied the phylogeography of the Rufous-fronted Thornbird (Phacellodomus rufifrons), a widespread dry forest bird with a disjunct distribution closely matching that of the biome itself. We sequenced mtDNA and used ddRADseq to sample 7,167 genome-wide single-nucleotide polymorphisms from 74 P. rufifrons individuals across its range. We found low genetic differentiation over two prominent geographic breaks - particularly across a 1,000 km gap between populations in Bolivia and Northern Peru. Using demographic analyses of the joint site frequency spectrum, we found evidence of recent divergence without subsequent gene flow across those breaks. By contrast, parapatric morphologically distinct populations in northeastern Brazil show high genetic divergence with evidence of recent gene flow. These results, in combination with our paleoclimate species distribution modelling, support the idea that currently disjunct patches of dry forest were more connected in the recent past, probably during the Middle and Late Pleistocene. This notion fits the major predictions of the Pleistocene Arc Hypothesis and illustrates the importance of comprehensive genomic and geographic sampling for examining biogeographic and evolutionary questions in complex ecosystems like Neotropical dry forests.


Assuntos
Aves , Ecossistema , Polimorfismo de Nucleotídeo Único , Animais , Aves/genética , Bolívia , Brasil , Florestas , Variação Genética , Peru , Filogenia , Filogeografia , Polimorfismo de Nucleotídeo Único/genética
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