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1.
An Acad Bras Cienc ; 96(2): e20230707, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38747790

RESUMO

Urban parks are not only important for the wellbeing of the human population, but are also widely considered to be potentially important sites for the conservation of biodiversity. However, they may offer risk parasitic infections, such as schistosomiasis and fascioliasis, which are both transmitted by freshwater snails. The present study investigated the occurrence of freshwater gastropods in urban parks of the Brazilian city of Rio de Janeiro, and their possible infection by helminths of medical-veterinary importance. Gastropods were collected from six parks (2021 - 2022) and examined for the presence of larval helminths. In all, 12 gastropod species from different families were collected: Ampullariidae, Assimineidae, Burnupidae, Lymnaeidae, Physidae, Planorbidae, Succineidae, and Thiaridae. The parasitological examination revealed cercaria of three types in five snail species, with the Pleurolophocerca cercariae type in Melanoides tuberculata (the most abundant species), Echinostoma cercariae in Physella acuta and Pomacea maculata, and Virgulate cercariae, in Pomacea sp. and Pomacea maculata. None of the Biomphalaria tenagophila and Pseudosuccinea columella (the most frequent species) specimens were parasitized by Schistosoma mansoni or Fasciola hepatica, respectively. Even so, some parks may represent a considerable potential risk for transmission of both Schistosoma mansoni and Fasciola hepatica, given the presence of these gastropod vectors and the frequent contact of visitors with the waterbodies.


Assuntos
Água Doce , Gastrópodes , Parques Recreativos , Animais , Brasil/epidemiologia , Água Doce/parasitologia , Gastrópodes/parasitologia , Gastrópodes/classificação , Humanos , Caramujos/parasitologia
2.
An Acad Bras Cienc ; 96(suppl 2): e20230742, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38896600

RESUMO

FioAntar, FIOCRUZ's research project in Antarctica, is based on the One Health approach. FioAntar aims to generate relevant information that will help reduce the risk of future pandemics and improve the search for chemical compounds and new biological molecules. After four expeditions to Antarctica under the scope of PROANTAR, Fiocruz has identified Influenza H11N2 virus in environmental fecal samples, as well as Histoplasma capsulatum and Bacillus cereus in soil samples. In addition, in a prospective virome analysis from different lakes in the South Shetland Islands, six viral orders were described, supporting future research related to the biodiversity and viral ecology in this extreme ecosystem. Our findings of environmental pathogens of public health importance are a warning about the urgency of establishing a surveillance agenda on zoonoses in Antarctica due to the imminent risks that ongoing environmental and climate changes impose on human health across the planet. FioAntar strives to establish a comprehensive surveillance program across Antarctica, monitoring circulation of pathogens with the potential to transcend continent boundaries, thereby mitigating potential spread. For Fiocruz, Antarctica signifies a new frontier, teeming with opportunities to explore novel techniques, refine established methodologies, and cultivate invaluable knowledge.


Assuntos
Monitoramento Ambiental , Regiões Antárticas , Humanos , Monitoramento Ambiental/métodos , Saúde Única , Animais , Saúde Pública
3.
Mol Ecol ; 32(7): 1739-1759, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36617622

RESUMO

The influence of genetic drift on population dynamics during Pleistocene glacial cycles is well understood, but the role of selection in shaping patterns of genomic variation during these events is less explored. We resequenced whole genomes to investigate how demography and natural selection interact to generate the genomic landscapes of Downy and Hairy Woodpecker, species codistributed in previously glaciated North America. First, we explored the spatial and temporal patterns of genomic diversity produced by neutral evolution. Next, we tested (i) whether levels of nucleotide diversity along the genome are correlated with intrinsic genomic properties, such as recombination rate and gene density, and (ii) whether different demographic trajectories impacted the efficacy of selection. Our results revealed cycles of bottleneck and expansion, and genetic structure associated with glacial refugia. Nucleotide diversity varied widely along the genome, but this variation was highly correlated between the species, suggesting the presence of conserved genomic features. In both taxa, nucleotide diversity was positively correlated with recombination rate and negatively correlated with gene density, suggesting that linked selection played a role in reducing diversity. Despite strong fluctuations in effective population size, the maintenance of relatively large populations during glaciations may have facilitated selection. Under these conditions, we found evidence that the individual demographic trajectory of populations modulated linked selection, with purifying selection being more efficient in removing deleterious alleles in large populations. These results highlight that while genome-wide variation reflects the expected signature of demographic change during climatic perturbations, the interaction of multiple processes produces a predictable and highly heterogeneous genomic landscape.


Assuntos
Aves , Genômica , Animais , Genoma , Seleção Genética , Densidade Demográfica , Nucleotídeos , Variação Genética/genética
4.
An Acad Bras Cienc ; 95(suppl 3): e20230741, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126386

RESUMO

Numerous Antarctic species are recognized as reservoirs for various pathogens, and their migratory behavior allows them to reach the Brazilian coast, potentially contributing to the emergence and circulation of new infectious diseases. To address the potential zoonotic risks, we conducted surveillance of influenza A virus (IAV) and coronaviruses (CoVs) in the Antarctic Peninsula, specifically focusing on different bird and mammal species in the region. During the summer of 2021/2022, as part of the Brazilian Antarctic Expedition, we collected and examined a total of 315 fecal samples to target these respiratory viruses. Although we did not detect the viruses of interest during this particular expedition, previous research conducted by our team has shown the presence of the H11N2 subtype of influenza A virus in penguin fecal samples from the same region. Given the continuous emergence of new viral strains worldwide, it is crucial to maintain active surveillance in the area, contributing to strengthening integrated One Health surveillance efforts.


Assuntos
Infecções por Coronavirus , Vírus da Influenza A , Influenza Aviária , Spheniscidae , Animais , Regiões Antárticas , Conduta Expectante , Influenza Aviária/epidemiologia , Filogenia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Mamíferos
5.
Emerg Infect Dis ; 28(10): 2100-2104, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36148943

RESUMO

We detected Histoplasma capsulatum in soil and penguin excreta in the Antarctic Peninsula by sequencing after performing species-specific PCR, confirming previous observations that this pathogen occurs more broadly than suspected. This finding highlights the need for surveillance of emerging agents of systemic mycoses and their transmission among regions, animals, and humans in Antarctica.


Assuntos
Histoplasmose , Micoses , Animais , Regiões Antárticas , Histoplasma/genética , Histoplasmose/diagnóstico , Histoplasmose/epidemiologia , Histoplasmose/veterinária , Humanos , Solo
6.
Environ Res ; 193: 110525, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33259786

RESUMO

Sediment dredging impacts coastal environments by promoting the resuspension of fine particles and remobilization of contaminants that may trigger toxic effects. In this study, we evaluated the sediment quality in harbor areas of Mucuripe bay, a semi-arid ecosystem located in Ceará state (Brazil), which is subject to dredging activities. A sampling survey was conducted right after dredging operations and data compared to another survey performed prior dredging. Sediments were analyzed for fine particles, organic carbon, nutrients, metals, hydrocarbons, and tributyltin (TBT). Toxicity of whole-sediment and liquid phase exposures were also determined. The concentrations of Cd, Cr, Cu, and Zn decreased after dredging, which was confirmed by the geoaccumulation index. Levels of TBT dropped while phosphorus, aliphatic and polycyclic aromatic hydrocarbons increased. Toxic effects persisted, indicating a post-dredging recontamination combined with other sources such as urban runoff, wastewater discharges, harbor activities, and antifouling particles. Data from Mucuripe and Pecém harbors were compiled and site-specific sediment quality values (SQVs) were developed by using multivariate methods. The threshold values proposed by our study were lower and more effective to predict toxicity compared to international guidelines, indicating levels of contamination for this tropical region in which toxic effects may occur. Considering the large geographic area with different sediment characteristics of the Brazilian coast, this study represents a significant contribution to sediment toxicity assessment of dredging activities in semi-arid environments.


Assuntos
Sedimentos Geológicos , Poluentes Químicos da Água , Brasil , Ecossistema , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
7.
Ecotoxicology ; 30(10): 2109-2118, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34618289

RESUMO

Accidents involving fuels and oil spills are among the main sources of hydrocarbons to the marine ecosystems and often damage the biota. Diesel and bunker oil are two examples of fuels with broad application that release hydrocarbons to the aquatic environment and little is known about their toxicity on tropical organisms. This study aimed to assess the toxicity of the water-soluble fraction (WSF) of diesel and bunker oils to neotropical marine invertebrates. Commercial fuels were purchased for WSF extraction, analyzed for total petroleum hydrocarbons (TPH), and polycyclic aromatic hydrocarbons (PAHs), and acute and chronic toxicity determined. The WSF analyzed contained varied levels of TPH and PAHs mixtures, especially low molecular weight PAHs; bunker WSF presented higher amounts of TPH and PAHs. Both WSFs tested produced significant mortality of the brine shrimp Artemia salina, affected the reproduction rate of the copepod Nitokra sp, and impaired the embryo-larval development of the mussel Perna perna and of the sea urchin Lytechinus variegatus. In general WSF from diesel was more toxic to the organisms tested, but bunker WSF was more toxic to embryos of L. variegatus. Toxicity started from concentrations of 3% WSF, which can be environmentally relevant after an oil spill, indicating that marine biota may be adversely affected in short term.


Assuntos
Copépodes , Poluição por Petróleo , Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Animais , Ecossistema , Hidrocarbonetos/toxicidade , Petróleo/toxicidade , Poluição por Petróleo/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
8.
Plant Dis ; 105(12): 4051-4059, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34270912

RESUMO

Wheat blast, caused by Pyricularia oryzae Triticum lineage, is a major constraint to wheat production, mainly in the tropics of Brazil, where severe epidemics have been more frequent. We analyzed disease and wheat yield data from 42 uniform field trials conducted over 9 years (2012 to 2020) to assess whether the percent control and yield response were influenced by fungicide type, region (tropical or subtropical), and year. Six treatments were selected, all evaluated in at least 19 trials. Two fungicides were applied as solo active ingredients (MANCozeb, and TEBUconazole), and four were premixes (AZOXystrobin plus TEBU, TriFLoXystrobin plus PROThioconazole, TFLX plus TEBU, and PYRAclostrobin plus EPOXiconazole). Percent control, calculated from back-transforming estimates by a meta-analysis network model fitted to the log of the means, ranged from 43 to 58%, with all but PYRA plus EPOX showing efficacy >52% on average, not differing among them. The variation in both efficacy and yield response was explained by region, and all but TEBU performed better in the subtropics than in the tropics. Yield response from using three sequential sprays was approximately two times greater in the subtropics (319 to 532 kg/ha) than in the tropics (149 to 241.3 kg/ha). No significant decline in fungicide efficacy or yield response was observed in 9 years of study for any of the fungicides. These results reinforce the need to improve control by adopting an integrated management approach in the tropics given poorer performance and lower profitability, especially for the premixes, than in the subtropics.


Assuntos
Fungicidas Industriais , Brasil , Fungicidas Industriais/farmacologia , Doenças das Plantas/prevenção & controle , Triticum
9.
Mol Ecol ; 29(16): 3085-3102, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32621770

RESUMO

Spatial patterns of intraspecific variation are shaped by geographical distance among populations, historical changes in gene flow and interactions with local environments. Although these factors are not mutually exclusive and operate on both genomic and phenotypic variation, it is unclear how they affect these two axes of variation. We address this question by exploring the predictors of genomic and phenotypic divergence in Icterus gularis, a broadly distributed Middle American bird that exhibits marked geographical variation in body size across its range. We combined a comprehensive single nucleotide polymorphism and phenotypic data set to test whether genome-wide genetic and phenotypic differentiation are best explained by (i) isolation by distance, (ii) isolation by history or (iii) isolation by environment. We find that the pronounced genetic and phenotypic variation in I. gularis are only partially correlated and differ regarding spatial predictors. Whereas genomic variation is largely explained by historical barriers to gene flow, phenotypic diversity can be best predicted by contemporary environmental heterogeneity. Our genomic analyses reveal strong phylogeographical structure coinciding with the Chivela Pass at the Isthmus of Tehuantepec that was formed during the Pleistocene, when populations were isolated in north-south refugia. In contrast, we found a strong association between body size and environmental variables, such as temperature and precipitation. The relationship between body size and local climate is consistent with a pattern produced by either natural selection or environmental plasticity. Overall, these results provide empirical evidence for why phenotypic and genomic data are often in conflict in taxonomic and phylogeographical studies.


Assuntos
Icterícia , Passeriformes , Animais , Variação Biológica da População , Fluxo Gênico , Variação Genética , Genética Populacional , Genômica , Passeriformes/genética , Estados Unidos
10.
Langmuir ; 36(32): 9578-9585, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32672975

RESUMO

Photodynamic therapy (PDT) is promising for bacterial inactivation since cellular internalization of photosensitizers (PS) is not crucial for the treatment effectiveness. Photoinduced damage in the lipid envelope may already induce microbial inactivation, which requires PS capable of easily penetrating into the membrane. Herein, we report on the insertion of the PS eosin decyl ester (EosDec) into Langmuir films of 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE), 1,2-dioleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (DOPG), and cardiolipin (CLP) used as mimetic systems of bacterial membranes. Surface pressure isotherms and polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS) indicated that the hydrophobic nature of EosDec favored deeper penetration in all the phospholipid monolayers. The incorporation of EosDec led to monolayer expansion, especially in the anionic DOPG and CLP owing to repulsive electrostatic interactions, and induced disorder in the lipid chains. Light irradiation of DOPE, DOPG, and CLP monolayers containing EosDec increased the rate of material loss to the subphase, which is attributed to cleavage of lipid chains triggered by contact-dependent reactions between excited states of EosDec and lipid unsaturations. The latter is key for membrane permeabilization and efficiency in microbial inactivation.


Assuntos
Ésteres , Fosfolipídeos , Amarelo de Eosina-(YS) , Interações Hidrofóbicas e Hidrofílicas , Membranas Artificiais , Fármacos Fotossensibilizantes/farmacologia
11.
Bull Environ Contam Toxicol ; 102(3): 310-315, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30688999

RESUMO

The present study assessed biochemical responses as sublethal endpoints in the polychaete Armandia agilis exposed to contaminated sediments to in order to assess its potential use as a test organism. Sediment samples from several locations at a dredging site were obtained and used in whole-sediment exposures. Samples were tested with A. agilis to determine the 10-day toxicity of the 100% sample and the enzymatic activity of catalase (CAT), glutathione-S-transferase (GST) and acetylcholinesterase (AChE) biochemical measurements made in whole-body homogenates of a subset of the surviving organisms. Biochemical responses reported in A. agilis were not statistically different from the reference site sediment, however, the integrated analysis demonstrated that contaminants bound to sediment samples influenced the sublethal effects.


Assuntos
Sedimentos Geológicos/química , Poliquetos/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/metabolismo , Animais , Catalase/metabolismo , Monitoramento Ambiental/métodos , Glutationa Transferase/metabolismo , Poliquetos/enzimologia , Testes de Toxicidade
12.
Environ Sci Technol ; 52(5): 3146-3155, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29397703

RESUMO

Diuron is a herbicide used in agricultural and urban settings and also as an antifouling agent. Recent studies have indicated sublethal responses of diuron in the endocrine system of fish and amphibians. Given the potential of climate change to also alter fish endocrinology, the combination of environmental stressors with diuron may contribute to its sublethal toxicity. In this study, the effects of temperature and salinity on thyroid targets of diuron were assessed in juveniles of the estuarine fish Menidia beryllina under different conditions of salinity (10 and 20‰) and temperature (10 and 20 °C). Environmentally relevant concentrations of diuron affected the growth, and the higher temperature reduced the condition factor of animals. Increased levels of T3 were observed in fish from all treatments, and at 10 °C, T4 levels were augmented at 10‰ but reduced at 20‰. Increased gene expression of deiodinases at 20‰ in both temperatures suggests the influence of salinity on the regulation of hormone imbalance via deiodination pathway activation. Decreased transcripts of thyroid and growth hormone receptors were also observed following diuron treatment. These results indicate that changes in environmental stressors may have significant impacts on the ecological risk of diuron in estuarine fish.


Assuntos
Desinfetantes , Diurona , Animais , Peixes , Salinidade , Temperatura
13.
Diabetes Obes Metab ; 19(1): 133-141, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27717236

RESUMO

AIMS: Low serum 25-hydroxyvitamin-D (25(OH)D) concentrations are associated with insulin resistance, ß-cell dysfunction and type 2 diabetes. We conducted a 24-week double-blind, randomized, placebo-controlled trial to examine the effect of 28 000 IU of vitamin D3 once weekly on plasma glucose after a 2 hour-75 g oral glucose tolerance test (2hrPC glucose), insulin sensitivity and ß-cell function. STUDY DESIGN AND METHODS: A total of 71 participants with serum 25(OH)D ≤65 nmol/L, impaired fasting glucose and elevated glycated hemoglobin were randomly assigned to receive 28 000 IU of vitamin D3 (VitD; n = 35) or placebo (n = 36) in cheese once weekly for 24 weeks. The primary outcome was the change in 2hPC glucose. Secondary outcomes were fasting glucose, fasting and postprandial insulin, indices of insulin sensitivity and ß-cell function, glycated hemoglobin and lipid profile. Participants underwent an oral glucose tolerance test to determine 2hPC glucose. RESULTS: Mean baseline serum 25(OH)D was 48.1 and 47.6 nmol/L in the VitD and placebo groups, respectively. Serum 25(OH)D significantly increased to 98.7 nmol/L (51 nmol/L increase; P < .0001) in the VitD group. No significant differences in fasting ( P = .42) or 2hPC glucose ( P = .55) or other indices of glucose metabolism, including ß-cell function and insulin sensitivity, were observed between groups. A subgroup analysis of individuals with 25(OH)D < 50 nmol/L and prediabetes did not change these results. The VitD group exhibited a significant reduction in LDL cholesterol (-0.27 vs 0.01 mmol/L, P = .03). CONCLUSION: Weekly doses of vitamin D3 in individuals with suboptimal vitamin D levels who were at risk for type 2 diabetes did not improve oral glucose tolerance or markers of glycaemic status.


Assuntos
Glicemia/metabolismo , Colecalciferol/uso terapêutico , Resistência à Insulina , Estado Pré-Diabético/metabolismo , Deficiência de Vitamina D/tratamento farmacológico , Vitaminas/uso terapêutico , Adulto , LDL-Colesterol/metabolismo , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/metabolismo , Suplementos Nutricionais , Método Duplo-Cego , Jejum , Feminino , Teste de Tolerância a Glucose , Hemoglobinas Glicadas/metabolismo , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial , Estado Pré-Diabético/epidemiologia , Risco , Vitamina D/análogos & derivados , Vitamina D/metabolismo , Deficiência de Vitamina D/epidemiologia , Deficiência de Vitamina D/metabolismo
14.
Ecotoxicol Environ Saf ; 135: 137-151, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27723466

RESUMO

Tropical marine environments are rich in biodiversity and the presence of harbor activities in these areas can harm the coastal ecosystems. In this study, we assessed sediment quality of two harbors from a tropical region in Brazil by applying multiple lines-of-evidence approach. This approach included the integration of results on: (1) grain size, organic matter, organic carbon, nitrogen, phosphorus, trace metals, polycyclic aromatic hydrocarbons, linear alkylbenzenes, and tributyltin; (2) acute toxicity of whole sediments and chronic toxicity of liquid phases; and (3) benthic community descriptors. Our results revealed that the main contaminants detected in sediments from Mucuripe and Pecém Harbors were chromium, copper, nitrogen, zinc, and tributyltin. These toxicants arise from typical harbor activities. However, the changes in benthic composition and structure appear to depend on a combination of physical impacts, such as the deposition of fine sediments and the toxic potential of contaminants, especially in Mucuripe. Thus, apart from toxicants physical processes are important in describing risks. This information may assist in management and conservation of marine coastal areas.


Assuntos
Sedimentos Geológicos/análise , Navios , Poluentes Químicos da Água/análise , Derivados de Benzeno/análise , Brasil , Monitoramento Ambiental , Metais/análise , Nitrogênio/análise , Fósforo/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Compostos de Trialquitina/análise , Clima Tropical
15.
Genetica ; 144(2): 139-46, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26862083

RESUMO

Eugenia dysenterica DC. (Myrtaceae) is a perennial tree producing edible fruits and ornamental flowers of potential value widely distributed in Brazilian "Cerrados" (savannas), but available genetic resources and potential for future breeding programs must be evaluated. Here we evaluated the reproductive system and pollen-mediated gene flow in one generation of Eugenia dysenterica germplasm collection of Agronomy School, Federal University of Goiás (in Goiânia city, Central Brazil). We collected leaves from all adults from the germplasm collection (682 plants) and seeds (542) from 23 mother-trees. Genotypes were obtained for seven microsatellite loci. Genetic diversity was high and did not significantly differ between adults (H e = 0.777) and progeny arrays (H e = 0.617). Our results showed that E. dysenterica has an allogamous mating system in the germplasm collection (t m = 0.957), but with high and significant biparental inbreeding (t m - t s = 0.109). Because sibs are very close to each other, mating between closely related individuals is likely. Paternity correlation was also relatively high, indicating a 11.9 % probability that a randomly chosen pair of outcrossed progeny from the same array are full sibs. The maximum pollen dispersal distance (224 m), estimated using assignment test, corresponded to the boundaries of the orchard. We were able to assign the paternity to only 64 % of the 349 seeds analyzed, indicating potential pollen immigration to the germplasm collection. The variance effective population size estimated for one maternal family in the germplasm collection (N ev = 3.42) is very close to the theoretical maximum value for half-sibs (Nev = 4.0). Because E. dysenterica has a long life cycle and generation time, the maintenance of an effective population size of at least 100 in the germplasm collection is suggested, which can be achieved by maintaining a seed-trees number around 30 individuals.


Assuntos
Eugenia/genética , Variação Genética , Genética Populacional , Pólen/genética , Brasil , DNA de Plantas/genética , Fluxo Gênico , Genótipo , Endogamia , Repetições de Microssatélites , Densidade Demográfica , Reprodução/genética , Sementes/genética , Análise de Sequência de DNA
17.
Ecotoxicol Environ Saf ; 112: 162-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25463867

RESUMO

The biomonitoring of fish using biomarkers represents a useful tool for the assessment of aquatic pollution. This study evaluated the sublethal toxic effects of aquatic pollution on fish collected from a site contaminated by metals. Water and fish (Oreochromis niloticus) samples were collected from a pond in the Parque Ecológico do Tietê (PET) that lies along the Tietê River (São Paulo, Brazil), and from a control site (an experimental fish farm). The metal content of the water was evaluated, and fish were used to examine the properties of gill mucus and blood. The PET fish were evaluated for alterations in the in vitro transportability of mucus and changes in blood properties (e.g., cell volume, hemoglobin concentration, red blood cells, and white blood cell count). The results of the water analyzes indicated metal levels above the legal standards for Fe (0.71 mg/L), Ni (0.06 mg/L), Mn (0.11 mg/L), and Pb (0.48 mg/L). Compared to the controls, the hematologic parameter analyzes of PET fish revealed significantly higher numbers of erythrocytes (RBC), leukocytes (WBC), lymphocytes, erythroblasts, and Mean Corpuscular Volume (MCV); however, the hemoglobin content and Mean Corpuscular Hemoglobin Concentration (MCHC) values were significantly lower. The frequencies of nuclear abnormalities and micronuclei were significantly higher and the mucociliary transport was significantly lower in PET fish than in the controls. These results suggest that fish from the contaminated site exhibit a series of physiological responses, which probably indicate health disturbances. Furthermore, the results suggest that blood and mucus are promising, non-destructive targets for use in the monitoring of pollution.


Assuntos
Ciclídeos/metabolismo , Metais/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Brasil , Monitoramento Ambiental , Testes Hematológicos , Metais/análise , Metais/metabolismo , Muco/efeitos dos fármacos , Muco/metabolismo , Lagoas/química , Poluentes Químicos da Água/sangue , Poluentes Químicos da Água/metabolismo
18.
Genome Biol Evol ; 16(1)2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-38236173

RESUMO

Geographic barriers are frequently invoked to explain genetic structuring across the landscape. However, inferences on the spatial and temporal origins of population variation have been largely limited to evolutionary neutral models, ignoring the potential role of natural selection and intrinsic genomic processes known as genomic architecture in producing heterogeneity in differentiation across the genome. To test how variation in genomic characteristics (e.g. recombination rate) impacts our ability to reconstruct general patterns of differentiation between species that cooccur across geographic barriers, we sequenced the whole genomes of multiple bird populations that are distributed across rivers in southeastern Amazonia. We found that phylogenetic relationships within species and demographic parameters varied across the genome in predictable ways. Genetic diversity was positively associated with recombination rate and negatively associated with species tree support. Gene flow was less pervasive in genomic regions of low recombination, making these windows more likely to retain patterns of population structuring that matched the species tree. We further found that approximately a third of the genome showed evidence of selective sweeps and linked selection, skewing genome-wide estimates of effective population sizes and gene flow between populations toward lower values. In sum, we showed that the effects of intrinsic genomic characteristics and selection can be disentangled from neutral processes to elucidate spatial patterns of population differentiation.


Assuntos
Genoma , Genômica , Animais , Filogenia , Aves/genética , Demografia , Seleção Genética
19.
Environ Toxicol Chem ; 43(2): 374-384, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37933775

RESUMO

Cigarette butts (CBs) are the most common type of beach litter worldwide and contain a complex mixture of chemicals. Given the recent interest in this emerging problem, it is important to assess the toxicity of CB leachates to a range of species from different regions, sensitivities, and ecological traits. We evaluated the waterborne toxicity of smoked CB to tropical invertebrates. Leachates were prepared in the laboratory and characterized for trace elements (Mn, Fe, Co, Ni, Cu, Zn, As, Cd, and Pb), ammonia nitrogen, and polycyclic aromatic hydrocarbons. Then a set of toxicity tests with marine invertebrates was performed as follows: the brine shrimp Artemia sp. (nontoxic); the amphipod Tiburonella viscana (median lethal concentration [LC50] of 0.038 CB/L); the tanaid Monokalliapseudes schubarti (LC50 of 0.126 CB/L); the copepods Tisbe biminiensis (median effect concentration [EC50] of 0.038 CB/L) and Nitokra sp. (EC50 of 0.009 CB/L); pluteus stage larvae of the sea urchin Echinometra lucunter (EC50 of 0.152 CB/L); the sand dollar Mellita quinquiesperforata (EC50 of 0.054 CB/L); and D-stage larvae of the mussel Perna perna (EC50 of 0.005 CB/L). The predicted no-effect concentration was estimated using species sensitivity distribution, producing a 5th percentile hazard concentration of 0.015 CB/L. This preliminary threshold allowed us to estimate the potential impact of a single CB to 67 L of seawater via leaching, contributing to the advancement of knowledge regarding the contamination, toxicity, and ecological risks of cigarette waste. Environ Toxicol Chem 2024;43:374-384. © 2023 SETAC.


Assuntos
Invertebrados , Produtos do Tabaco , Animais , Produtos do Tabaco/toxicidade , Organismos Aquáticos , Testes de Toxicidade , Larva
20.
Mar Pollut Bull ; 204: 116561, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38838392

RESUMO

In 2015, > 460,000 L of aqueous film-forming foam (AFFF) and fire suppressors containing per- and polyfluoroalkyl substances (PFAS) were used to combat a fire at a petrochemical fuel storage terminal in the Port of Santos (Brazil). Sediments from seven sites were sampled repeatedly from 2 weeks to 1 year after the fire (n = 30). Æ©15PFAS concentrations ranged from 115 to 15,931 pg g-1 dry weight (dw). Perfluorooctane sulfonic acid (PFOS) was the most frequently detected compound with concentrations ranging from 363 to 4517 (average = 1603) pg g-1dw to <47.1 to 642 (average = 401) pg g-1 dw, followed by perfluorohexanoic acid (PFHxA) (from 38.8 to 219 (average = 162) pg g-1 dw after 15 days and from <20.8 to 161 (average = 101) pg g-1 dw one year later). Together, the hydrodynamics and fire events documented in the region were important features explaining the spread of PFAS.


Assuntos
Ácidos Alcanossulfônicos , Monitoramento Ambiental , Fluorocarbonos , Poluentes Químicos da Água , Fluorocarbonos/análise , Poluentes Químicos da Água/análise , Ácidos Alcanossulfônicos/análise , Brasil , Sedimentos Geológicos/química , Caproatos/análise
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