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1.
Sci Total Environ ; 901: 165955, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-37536601

RESUMO

Research on nanotechnology with applications in agriculture has been gathering attention because it may achieve a good balance between agricultural production and environmental integrity. Among the vast nanomaterials, layered double hydroxides (LDHs) are a promising solution for supplying crops with macro- and/or micronutrients. Still, little is known about their safety implications for non-target organisms, such as soil invertebrates. The habitat function of soils might be impacted by potential stressors, which can be assessed through avoidance behaviour tests. This study aimed to assess the effect of two innovative agriproducts, Zn-Al-NO3 LDH and Mg-Al-NO3 LDH, on the avoidance behaviour of the enchytraeid Enchytraeus crypticus and the collembolan Folsomia candida, over time. Simultaneously, Zn and Mg potential release from LDHs to soil was evaluated. Overall, the behaviour of soil invertebrates differed between species, with enchytraeids being more sensitive to LDHs-treated soils than collembolans, possibly explained by their different physiological traits. The behaviour of soil organisms also depended on the LDH structural composition and was time-variable. Soil treated with Zn-Al-NO3 LDH was perceived as less favourable compared to Mg-Al-NO3 LDH, which was preferred to clean soil at most tested concentrations. LDHs toxicity was partly, but not exclusively, related to Zn and Mg release. Cations release over time was demonstrated in the chemical assessment. Still, LDHs toxicity to soil invertebrates decreased as increasing AC50 values were derived over time. Slower dissolution over time might explain the decrease in toxicity. Our study demonstrates that both soil invertebrates could sense LDHs in soil and eventually adapt their behaviour by avoiding or preferring, according to the type and level of LDH present.

2.
Chemosphere ; 307(Pt 1): 135583, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35792207

RESUMO

Ultraviolet radiation (UV) and triclosan (TCS) affect the early development of marine fish; however, the corresponding molecular mechanisms are still not fully understood. Therefore, this work aims to study the effects of the single and combined exposure to these stressors during the thyroid-regulated metamorphosis of the flatfish Solea senegalensis. Sub-lethal exposure (5.89 kJ m-2 UV and/or 0.546 and 1.090 mg L-1 TCS for 48 h) was performed at the beginning of metamorphosis (13 days after hatching, dah), followed by a period in clean media until complete metamorphosis (24 dah). Malformations, metamorphosis progression, length, behavior and the expression of thyroid axis-related genes were studied. TCS induced malformations, decreased swimming performance, and induced metamorphosis acceleration at 15 dah, followed by a significant metamorphosis delay. Such effects were more noticeable in the presence of UV. The down-regulation of five thyroid axis-related genes occurred after exposure to TCS (15 dah), and after 9 days in clean media two genes were still down-regulated. UV exposure increased the effect of TCS by further down-regulating gene expression immediately after the exposure. Since several effects persisted after the period in clean media, implications of these stressors (mainly TCS) on the ecological performance of the species are suggested.


Assuntos
Linguados , Triclosan , Animais , Linguados/genética , Linguados/metabolismo , Larva , Metamorfose Biológica , Triclosan/metabolismo , Raios Ultravioleta
3.
Chemosphere ; 297: 134069, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35218782

RESUMO

In the recent years, marine heatwaves (MHWs) have caused devastating impacts on marine life. The understanding of the combined effects of these extreme events and anthropogenic pollution is a vital challenge. In particular, the combined effect of MHWs on the toxicity of pharmaceuticals to aquatic life remains unclear. To contribute to these issues, the main goal of the present investigation was to evaluate how MHWs may increase caffeine (CAF) toxicity on the clam Ruditapes philippinarum and the mussel Mytilus galloprovincialis. Bioaccumulation levels and changes on oxidative stress, metabolic capacity and neurotoxic status related biomarkers were investigated. The obtained results revealed the absence of CAF accumulation in both species. However, the used contaminant generated in both bivalve species alteration on neurotransmission, detoxification mechanisms induction as well as cellular damage. The increase of antioxidant defence mechanisms was complemented by an increase of metabolic activity and decrease of energy reserves. The obtained results seemed magnified under a simulated MHWs, suggesting to a climate-induced toxicant sensitivities' response. On this perspective, understanding of how toxicological mechanisms interact with climate-induced stressors will provide a solid platform to improve effect assessments for both humans and wildlife.


Assuntos
Clima Extremo , Mytilus , Poluentes Químicos da Água , Animais , Cafeína/metabolismo , Cafeína/toxicidade , Humanos , Mytilus/metabolismo , Estresse Oxidativo , Espécies Sentinelas/metabolismo , Poluentes Químicos da Água/análise
4.
Chemosphere ; 286(Pt 2): 131675, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34358890

RESUMO

Caffeine has been identified as emerging contaminant of concern due to its widespread occurrence in the aquatic environment and potential to be biologically active. Recently, these concerns have been translated in an increasing research on its occurrence and effects on biota. However, there is still a limited knowledge on seawater matrices and the implications of caffeine presence in coastal and marine ecosystems are not fully known. The present review aims to fill these knowledge gaps, analysing the existing literature regarding the occurrence, effects and potential risks of caffeine residues to coastal ecosystems, contributing to the risk assessment of this psychoactive drug in the aquatic environment. The analysed literature reported caffeine concentrations in the coastal ecosystems, raising high concerns about the potential adverse impacts on the ecological safety and human health. Caffeine has been found in tissues from coastal and marine biota including microalgae, coral reefs, bivalves and fish due to bioaccumulation after chronic, long-term exposures in a contaminated environment. Additionally, caffeine residues had been demonstrated to have adverse impacts on aquatic organisms, at environmentally realistic concentrations, inducing oxidative stress and lipid peroxidation, neurotoxicity, changing energy reserves and metabolic activity, affecting reproduction and development and, in some cases, causing mortality. Considering the increasing adverse impacts of caffeine pollution in the coastal environment, this review highlights the urgent need to minimize the increasing load of caffeine to the aquatic ecosystems; being imperative the implementation of scientific programs and projects to classify effectively the caffeine as a high-priority environmentally hazardous emerging pollutant.


Assuntos
Bivalves , Poluentes Químicos da Água , Animais , Cafeína/análise , Cafeína/toxicidade , Ecossistema , Humanos , Água do Mar , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
5.
J Helminthol ; 95: e17, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33745470

RESUMO

The continuous use of synthetic anthelmintics against gastrointestinal nematodes (GINs) has resulted in the increased resistance, which is why alternative methods are being sought, such as the use of natural products. Plant essential oils (EOs) have been considered as potential products for the control of GINs. However, the chemical composition and, consequently, the biological activity of EOs vary in different plant cultivars. The aim of this study was to evaluate the anthelmintic activity of EOs from cultivars of Ocimum basilicum L. and that of their major constituents against Haemonchus contortus. The EOs from 16 cultivars as well the pure compound linalool, methyl chavicol, citral and eugenol were used in the assessment of the inhibition of H. contortus egg hatch. In addition, the composition of three cultivars was simulated using a combination of the two major compounds from each. The EOs from different cultivars showed mean Inhibition Concentration (IC50) varying from 0.56 to 2.22 mg/mL. The cultivar with the highest egg-hatch inhibition, Napoletano, is constituted mainly of linalool and methyl chavicol. Among the individual compounds tested, citral was the most effective (IC50 0.30 mg/mL). The best combination of compounds was obtained with 11% eugenol plus 64% linalool (IC50 0.44 mg/mL), simulating the Italian Large Leaf (Richters) cultivar. We conclude that different cultivars of O. basilicum show different anthelmintic potential, with cultivars containing linalool and methyl chavicol being the most promising; and that citral or methyl chavicol isolated should also be considered for the development of new anthelmintic formulations.


Assuntos
Anti-Helmínticos , Haemonchus , Ocimum basilicum , Óleos Voláteis , Extratos Vegetais , Animais , Anti-Helmínticos/farmacologia , Haemonchus/efeitos dos fármacos , Ocimum basilicum/química , Óleos Voláteis/farmacologia , Óvulo/efeitos dos fármacos , Extratos Vegetais/farmacologia
6.
Mar Pollut Bull ; 165: 112153, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33607451

RESUMO

This study evaluated mercury (Hg) in three coastal areas in the North Atlantic Ocean (Azores archipelago, Northwest Portugal and Southeast Mexico) and calculated their enrichment factor and geoaccumulation index. Hg presented greater affinity with fine sediment fraction. In all sampling areas the sites with proximity to possible Hg hotspots presented increased [Hg] in fine sediments. However, this fraction only represents less than 1% of the whole sediment, resulting in a significantly lower [Hg] in the total sediment fraction. After comparing [Hg] in the fine fraction and the values established by the Sediment Quality Guidelines, two sites in the Azores exceeded these values. Nevertheless, when considering the total sediment fraction, adverse biological effects are not expected to occur. Finally, both enrichment factor and geoaccumulation index indicated that the Hg present in 86% comes from natural sources and only sampling sites close to potential hotspots showed some degree of enrichment and contamination.


Assuntos
Mercúrio , Poluentes Químicos da Água , Oceano Atlântico , Açores , Monitoramento Ambiental , Sedimentos Geológicos , Mercúrio/análise , México , Portugal , Poluentes Químicos da Água/análise
7.
Environ Res ; 193: 110585, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33309824

RESUMO

Mercury (Hg) is a widespread pollutant across estuarine and coastal areas, raising concern on its potential impact on aquatic organisms. Hg may origin from natural and anthropogenic sources, being persistent and potentially toxic to biota, ultimately representing a serious risk to human health. Hg accumulation and toxicity may also induce reactive oxygen species (ROS) production in marine organisms, responsible for cell and tissue damage. Additionally, the temperature is undoubtedly an important environmental factor to consider regarding accumulation, due to its marked influence on the physiology and ecology of aquatic organisms. This study aimed to investigate the effect of different temperature scenarios (15, 20 and 25 °C) on the Hg accumulation in Pomatoschistus microps (Krøyer, 1838) liver and muscle, as well as on oxidative stress responses and energy metabolism, after short-term exposure to a naturally contaminated sediment with an environmentally relevant [Hg] (1.2 µg g-1). The results showed that Hg accumulation tends to increase along the temperature gradient with higher values of Hg accumulated in liver than in muscle tissue. The action of antioxidant enzymes and stress proteins seems to be effective in combating oxidative stress in the liver. Despite the action of antioxidant defences in the muscle, oxidative damage was observed at the protein level concomitantly with a decrease in aerobic energy production after exposure to Hg at higher temperatures. These findings are ecologically relevant and highlight the importance of further investigation of combined effects of Hg and other stressors, especially in a scenario of a changing climate where events leading to rapid alterations on water parameters are more frequent.


Assuntos
Mercúrio , Poluentes Químicos da Água , Animais , Humanos , Mercúrio/toxicidade , Estresse Oxidativo , Temperatura , Água , Poluentes Químicos da Água/toxicidade
8.
Chemosphere ; 264(Pt 1): 128403, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33007568

RESUMO

Natural populations are commonly exposed to sequential pulses of contaminants. Accordingly, this study aimed at testing the existence of an association between the tolerance to lethal levels of copper (Cu) and the survival recovery ability from pulsed partially lethal copper exposures in six clonal lineages of Daphnia longispina. It was hypothesized that the most tolerant genotypes would be the ones exhibiting a faster survival recovery from a pulsed contaminant exposure. For each clonal lineage, the intensity of pulses corresponded to the respective concentration of Cu causing 30% of mortality after 24h of exposure (LC30,24h). The initial hypothesis was not corroborated: obtained results showed no association between survival recovery and lethal tolerance to Cu. Nevertheless, some patterns could be detected. Firstly, the most sensitive lineages to lethal levels of copper revealed a faster survival recovery from a first Cu pulse comparatively to the most tolerant ones, though they were the most sensitive to a second pulse exposure. Secondly, the most tolerant lineages, though being more tolerant to a second exposure, exhibited the lowest survival recovery capacity after exposure to a first pulse of Cu. However, differences in the survival recovery capacity of the six clonal lineages after the exposure to the two pulses of Cu were not observed. Increasing the duration of the recovery period from 24h to 72h did not significantly alter mortality rates, except for the most sensitive and most tolerant clonal lineages. The results here obtained suggests that standard lethality assays may sub-estimate the toxicity of chemicals under realistic exposure scenarios, since sequential pulses are not infrequent in natural conditions.


Assuntos
Daphnia , Poluentes Químicos da Água , Animais , Bioensaio , Cobre/toxicidade , Genótipo , Poluentes Químicos da Água/toxicidade
9.
Tropical Biomedicine ; : 505-510, 2021.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-935083

RESUMO

@#Malaria, a mosquito-borne disease, is caused by protozoa of the genus Plasmodium and constitutes a serious public health problem. Because current insecticides used to control malaria face resistance due to continuous use, new alternatives are prompted. Considering this context, and the insecticidal potential of vertebrate venoms/secretions, crude and methanolic extracts from two frog species were tested as larvicides against Anopheles darlingi. Skin secretions of Rhinella marina and Rhaebo guttatus were obtained by manual stimulation. Then, methanol was added to obtain steroidal fractions from both venoms. Mosquitos were captured in suburban areas of Porto Velho and An. darlingi females were later fed with blood and stimulated to oviposit. The larvae were fed with fish food until the 3rd and 4th instars. For the larvicidal assays, crude secretions and methanolic fractions of both frog species were evaluated, and larvae mortality was recorded after 48 hours. Crude extracts and steroidal fractions from both species had larvicidal effects, with an LC50 of 127.5 and 133 ppm for the crude extract and steroidal fraction of R. marina, and an LC50 of 37.5 and 35.8 ppm for the crude extract and steroidal secretion of R. guttatus, respectively. The present work reports for the first time the larvicidal effects of the skin secretions from bufonid species occurring in the western Amazon region. Further studies should be carried out to investigate the purified components responsible for the observed activity.

10.
Mar Pollut Bull ; 160: 111665, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33181940

RESUMO

In vitro methods have gained rising importance in ecotoxicology due to ethical concerns. The aim of this study was to assess the single and combined in vitro effects of gold, as nanoparticle (AuNPs) and ionic (Au+) form, and the pharmaceutical gemfibrozil (GEM). Sparus aurata liver organ culture was exposed to gold (4 to 7200 µg·L-1), GEM (1.5 to 15,000 µg·L-1) and combination 80 µg·L-1 gold +150 µg·L-1 GEM for 24 h. Endpoints related with antioxidant status, peroxidative/genetic damage were assessed. AuNPs caused more effects than Au+, increasing catalase and glutathione reductase activities and damaging DNA and cellular membranes. Effects were dependent on AuNPs size, coating and concentration. GEM damaged DNA at an environmentally relevant concentration, 1.5 µg·L-1. Overall, the effects of the combined exposures were higher than the predicted, based on single exposures. This study showed that liver culture can be a useful model to study contaminants effects.


Assuntos
Nanopartículas Metálicas , Dourada , Animais , Genfibrozila/toxicidade , Ouro , Fígado , Nanopartículas Metálicas/toxicidade , Técnicas de Cultura de Órgãos
11.
J Hazard Mater ; 400: 123237, 2020 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-32947686

RESUMO

Gold nanorods (AuNR) have been explored for many applications, including innovative nanomedicines, which also might contribute to its increase in the environment, namely due to inadequate disposable of wastes into aquatic environments. Early-life stages of amphibians are usually aquatic and sensitive to chemical contamination. Accordingly, this study aimed to determine the sublethal effects of CTAB functionalized AuNR on Xenopus laevis tadpoles. As such, tadpoles were exposed to serial concentrations of AuNR for 72 h. A reduction in the rate of feeding (EC50 = 4 µg.L-1), snout to vent growth (EC50 = 5 µg.L-1) and weight gain (EC50 = 6 µg.L-1), was observed for AuNR-exposed tadpoles. Also, tadpoles actively avoided concentrations ≥ 4 µg.L-1 of AuNR, after 12 h of exposure. At the biochemical level, AuNR caused impairments in antioxidant and nervous system related enzymes. Exposure to CTAB alone caused a high mortality. Results indicated that CTAB functionalized AuNR may induce several sublethal effects that may compromise the organism's fitness. Avoidance behavior (which corresponds to the disappearance of organisms, thus, similar to their death), observed at concentrations matching those inducing sublethal effects, suggest that it should be considered in the risk assessment for amphibians.


Assuntos
Nanotubos , Poluentes Químicos da Água , Animais , Coloide de Ouro , Larva , Nanotubos/toxicidade , Xenopus laevis
12.
Ecotoxicol Environ Saf ; 203: 110957, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888620

RESUMO

Due to growing commercial interest as a fishing resource and its intermediate position in the marine trophic chains as both prey and predator, cephalopods can play an important role in mercury (Hg) transfer along the marine food webs, since they can bioaccumulate this metal in its tissues. Our study aims to analyze Hg accumulation in Loligo forbesi caught in the Azores Archipelago (Portugal) quantifying Hg in different tissues (mantle and stomach), as well in the squid stomach content, in order to evaluate the efficiency of Hg transfer from prey to predator. Hg data from the tissues was used to estimate the weekly tolerable Hg intake due to squid consumption. Overall data indicate that Hg measured in the stomach tissue (0.1 ± 0.01 µg g-1) was significantly higher than Hg levels found in the mantle (0.04 ± 0.001 µg g-1) and stomach contents (0.01 ± 0.001 µg g-1). BMF (bioaccumulation factor) was >1 for all the samples, indicating a biomagnification process from prey to predator. Hg concentration in the mantle tissue was correlated with mantle size; although females present higher Hg levels than males, the difference was found to be not related to gender but rather to the fact that females had larger bodies. Finally, considering the Hg concentration found in the mantle and the permitted Hg levels, it is advisable to consume up to 1050-1890g of squid per week, according to the regulatory agencies. Thus, our results indicate that, since these doses are respected, consumption of squids from the Azorean waters do not pose a risk to humans.


Assuntos
Bioacumulação , Exposição Dietética/análise , Monitoramento Ambiental/métodos , Loligo/metabolismo , Mercúrio/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Feminino , Cadeia Alimentar , Humanos , Masculino , Mercúrio/análise , Portugal , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise
13.
Neuropeptides ; 83: 102081, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32839009

RESUMO

Gyroxin is a thrombin-like toxin obtained from the venom of the South American rattlesnake, Crotalus durissus terrificus. Literature has reported "gyroxin syndrome" characterized, in mice, as series of aberrant motor behavior, known as barrel rotation, mainly after intraperitoneal administration. Despites several studies, a physiological mechanism of "gyroxin syndrome" are still not completely understood. In this context, alterations on the central nervous system (CNS), especially causing neurotoxic events, are pointed out as likely candidates. Then, we decided to investigate whether gyroxin induces alterations in glutamate release, one of the most important neurotransmitter involved in neurotoxicity. For that, we performed all experiments, in vitro, using a model of mice brain cortical synaptosomes. Notably, our results indicate that the administration of gyroxin on purified presynaptic brain cortical terminals resulted in an extracellular Ca2+- dependent raise in glutamate release. Indeed, our results also showed that gyroxin increases intrasynaptosomal calcium (Ca2+) levels through acting on voltage gated calcium channels (VGCC), specifically N and P/Q subtypes. Moreover, our data show that gyroxin increases exocytosis rate. Interestingly, these data suggest that gyroxin might induce neurotoxicity by increasing glutamate levels. However, future investigations are needed in order to elucidate the nature of the following events.


Assuntos
Cálcio/metabolismo , Córtex Cerebral/efeitos dos fármacos , Venenos de Crotalídeos/farmacologia , Ácido Glutâmico/metabolismo , Neurotoxinas/farmacologia , Sinaptossomos/efeitos dos fármacos , Animais , Córtex Cerebral/metabolismo , Camundongos , Sinaptossomos/metabolismo
14.
Environ Pollut ; 265(Pt B): 114993, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32806449

RESUMO

Among the most used non-steroidal anti-inflammatory drugs (NSAIDs), ketoprofen (KTF) assumes an important position. Nevertheless, its ecotoxicological effects in non-target organisms are poorly characterized, despite its use and frequency of occurrence in aquatic matrices. Thus, the aim of this study was to evaluate the possible toxicological effects of KTF contamination, in two freshwater species, Lemna minor and Daphnia magna, by measuring biochemical, physiological and population parameters. To attain this objective, both species were exposed to KTF at the same concentrations (0, 0.24, 1.2, 6 and 30 µg/L). L. minor plants were exposed during 4 d to these levels of KTF, and the enzymatic activity (catalase (CAT), glutathione S-transferases (GSTs) and carbonic anhydrase (CA)), and pigments content (chlorophylls a, b and total and carotenoids) were analyzed to evaluate the toxicity of this drug. D. magna was acutely and chronically exposed to KTF, and enzymatic activities (CAT, GSTs and cyclooxygenase (COX)), the feeding rates, and reproduction traits were assessed. In L.minor, KTF provoked alterations in all enzyme activities, however, it was not capable of causing any alteration in any pigment levels. On the other hand, KTF also provoked alterations in all enzymatic activities in D. magna, but did not affect feeding rates and life-history parameters. In conclusion, exposure to KTF, provoked biochemical alterations in both species. However, these alterations were not reflected into deleterious effects on physiological and populational traits of L. minor and D. magna.


Assuntos
Araceae , Cetoprofeno , Poluentes Químicos da Água , Animais , Daphnia , Água Doce
15.
Sci Total Environ ; 739: 139715, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32534307

RESUMO

Salicylic acid (SA) is a pharmaceutical drug that may exert toxic effects by its own; however, simultaneous exposure of plants to SA and to other substances, often results in the significant changes in the patterns of toxic response/resistance to these other sources of chemical stress. Thus, the aim of this work was to investigate the capacity of SA of modulating Lemna minor responses co-exposed to the pharmaceutical drug, diclofenac - DCF. To attain this objective, L. minor was exposed for 7 days, to DCF alone, and to combinations of DCF with SA. After exposure, biochemical, physiological and population endpoints were analyzed as follows: catalase (CAT) and glutathione S-transferases (GSTs) activities, pigments content (chlorophyll a (Chl a), b (Chl b) and total (TChl), carotenoids (Car) and [Chl a]/[Chl b] and [TChl]/[Car] ratios), and growth specific rate, fresh weight and root length. Single exposures to DCF were capable of causing effects in all analyzed endpoints. However, co-exposure of DCF with SA partially reverted these effects. Finally, we may suggest that SA is capable to prevent the toxicity of DCF in macrophytes, by modulating the toxic response of exposed plants.


Assuntos
Araceae , Poluentes Químicos da Água , Antioxidantes , Clorofila , Clorofila A , Diclofenaco , Ácido Salicílico
16.
Science ; 367(6485)2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32217702

RESUMO

Marine food-reliant subsistence systems such as those in the African Middle Stone Age (MSA) were not thought to exist in Europe until the much later Mesolithic. Whether this apparent lag reflects taphonomic biases or behavioral distinctions between archaic and modern humans remains much debated. Figueira Brava cave, in the Arrábida range (Portugal), provides an exceptionally well preserved record of Neandertal coastal resource exploitation on a comparable scale to the MSA and dated to ~86 to 106 thousand years ago. The breadth of the subsistence base-pine nuts, marine invertebrates, fish, marine birds and mammals, tortoises, waterfowl, and hoofed game-exceeds that of regional early Holocene sites. Fisher-hunter-gatherer economies are not the preserve of anatomically modern people; by the Last Interglacial, they were in place across the Old World in the appropriate settings.


Assuntos
Dieta , Homem de Neandertal , Exoesqueleto , Animais , Arqueologia , Oceano Atlântico , Aves , Cavernas , Peixes , Mamíferos , Nozes , Pinus , Portugal , Alimentos Marinhos , Tartarugas
17.
Aquat Toxicol ; 221: 105445, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32078886

RESUMO

Despite the widespread use of nanoparticles (NPs), there are still major gaps of knowledge regarding the impact of nanomaterials in the environment and aquatic animals. The present work aimed to study the effects of 7 and 40 nm gold nanoparticles (AuNPs) - citrate and polyvinylpyrrolidone (PVP) coated - on the liver proteome of the estuarine/marine fish gilthead seabream (Sparus aurata). After 96 h, exposure to AuNP elicited alterations on the abundance of 26 proteins, when compared to the control group. AuNPs differentially affected several metabolic pathways in S. aurata liver cells. Among the affected proteins were those related to cytoskeleton and cell structure, gluconeogenesis, amino acids metabolism and several processes related to protein activity (protein synthesis, catabolism, folding and transport). The increased abundance of proteins associated with energy metabolism (ATP synthase subunit beta), stress response (94 kDa glucose-regulated protein) and cytoskeleton structure (actins and tubulins) may represent the first signs of cellular oxidative stress induced by AuNPs. Although higher gold accumulation was found in the liver of S. aurata exposed to 7 nm PVP-AuNPs, the 7 nm cAuNPs were more bioactive, inducing more effects in liver proteome. Gold accumulated more in the spleen than in the other assessed tissues of S. aurata exposed to AuNPs, highlighting its potential role on the elimination of these NPs.


Assuntos
Ouro/toxicidade , Fígado/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Proteoma/metabolismo , Dourada/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Ácido Cítrico/química , Fígado/metabolismo , Redes e Vias Metabólicas/efeitos dos fármacos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Povidona/química , Proteômica , Propriedades de Superfície
18.
Sci Total Environ ; 716: 137026, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32036137

RESUMO

The question of whether gold (Au) is more toxic as nanoparticles or in its ionic form remains unclear and controversial. The present work aimed to clarify the effects of 96 h exposure to 4, 80 and 1600 µg·L-1 of 7 nm gold nanoparticles (AuNPs) - (citrate coated (cAuNPs) or polyvinylpyrrolidone coated (PVP-AuNPs)) - and ionic Au (iAu) on gilthead seabream (Sparus aurata). Effects at different levels of biological organization (behaviour, neurotransmission, biotransformation, oxidative stress/damage and genotoxicity) were assessed. cAuNPs induced oxidative stress and damage (lipid peroxidation increase), even at 4 µg·L-1, and reduced the ability of S. aurata to swim against a water flow at 1600 µg·L-1. Exposure to cAuNPs induced more adverse effects than exposure to PVP-AuNPs. All tested concentrations of Au (nano or ionic form) induced DNA breaks and cytogenetic damage in erythrocytes of S. aurata. Generally, iAu induced significantly more effects in fish than the nano form, probably associated with the significantly higher accumulation in the fish tissues. No fish mortality was observed following exposure to AuNPs, but mortality was observed in the group exposed to 1600 µg·L-1 of iAu.


Assuntos
Dourada , Animais , Bioacumulação , Ouro , Nanopartículas Metálicas , Estresse Oxidativo
19.
Sci Total Environ ; 713: 136659, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31955109

RESUMO

Microplastics (1 µm-5 mm), a ubiquitous and persistent marine pollutant, pose a severe threat to coral reefs when recently associated with physiological distress and increased diseases on corals. Studies conducted so far have only reported effects on scleractinian species. Knowledge about its effects on other corals (e.g. Order Zoantharia) remains uncovered, and responses at biochemical levels remain poorly documented. This study aimed to assess the potential effects induced by the presence of microplastics (1 and 10 mg L-1 low-density polyethylene, LDPE MP, or polyvinyl chloride, PVC MP) in the tropical and subtropical cosmopolitan species Zoanthus sociatus (order Zoantharia. Anthozoa: Hexacorallia), at organism level (survival and behaviour), endosymbionts (photosynthetic efficiency) and the cellular level (oxidative stress, detoxification capacity and energy metabolism). In a short-term exposure (96 h), this species was more sensitive to PVC MP. The presence of this polymer at a concentration of 10 mg L-1 caused a ten-fold higher adhesion to the coral epidermis, increased photosynthetic efficiency, lipid peroxidation, and antioxidant defences; without, however, inducing energetic costs. Although the observed physiological and biochemical effects did not compromise Z. sociatus survival in the short term, it does not rule out potential long-term (cumulative) effects that could endanger this and other physiologically similar species that underlie coral reefs.


Assuntos
Antozoários , Animais , Recifes de Corais , Microplásticos
20.
Br J Nutr ; 123(9): 1003-1012, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31964426

RESUMO

A child's diet contains nutrients and other substances that influence intestinal health. The present study aimed to evaluate the relations between complementary feeding, intestinal barrier function and environmental enteropathy (EE) in infants. Data from 233 children were obtained from the Brazilian site of the Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development Project cohort study. Habitual dietary intake from complementary feeding was estimated using seven 24-h dietary recalls, from 9 to 15 months of age. Intestinal barrier function was assessed using the lactulose-mannitol test (L-M), and EE was determined as a composite measure using faecal biomarkers concentrations - α-1-antitrypsin, myeloperoxidase (MPO) and neopterin (NEO) at 15 months of age. The nutrient adequacies explored the associations between dietary intake and the intestinal biomarkers. Children showed adequate nutrient intakes (with the exception of fibre), impaired intestinal barrier function and intestinal inflammation. There was a negative correlation between energy adequacy and L-M (ρ = -0·19, P < 0·05) and between folate adequacy and NEO concentrations (ρ = -0·21, P < 0·01). In addition, there was a positive correlation between thiamine adequacy and MPO concentration (ρ = 0·22, P < 0·01) and between Ca adequacy and NEO concentration (ρ = 0·23; P < 0·01). Multiple linear regression models showed that energy intakes were inversely associated with intestinal barrier function (ß = -0·19, P = 0·02), and fibre intake was inversely associated with the EE scores (ß = -0·20, P = 0·04). Findings suggest that dietary intake from complementary feeding is associated with decreased intestinal barrier function and EE in children.


Assuntos
Dieta/normas , Enterite/etiologia , Fenômenos Fisiológicos da Nutrição do Lactente , Intestinos/fisiologia , Brasil/epidemiologia , Aleitamento Materno , Estudos de Coortes , Enterite/epidemiologia , Feminino , Humanos , Lactente , Masculino , Estado Nutricional
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