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1.
Ecotoxicol Environ Saf ; 215: 112151, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33743402

RESUMO

The Water Framework Directive (WFD) was adopted in 2000 and is a common framework for water policy, management and protection in Europe. The WFD assesses specific parameters; however, it ignores indicators of ecosystem functioning and sub-individual performance. Reservoirs are strongly influenced by anthropogenic activities that promote their imbalance. Bioassays and biomarkers are useful tools to link the chemical, ecological and toxicological assessments in water quality assessments. These approaches can be complementary to WFD methodologies, allowing the detection of impacts on the ecosystem. This study evaluated if the biochemical parameters can improve the sensitivity of the biomonitoring strategy using bioassays with the standard species Daphnia magna, in the assessment of the ecological quality of water reservoirs. To this end, water samples of Portuguese reservoirs were analysed in three sampling periods (Autumn 2018 and Spring, Autumn 2019). In parallel, a physicochemical characterization of waters was performed. D. magna feeding rate assays were performed for 24 h. After exposure, metabolism, oxidative stress and lipid peroxidation biomarkers were evaluated. Feeding rate assays showed sensitivity to different reservoirs. Biomarkers showed a higher sensitivity and can therefore improve the sensitivity of the biomonitoring strategy using bioassays. Bioassays and biomarkers approach allowed to highlight potential sources of stress, more related to the quality of the seston than to chemical contamination. This work highlights the complementarity between bioassays and biomarkers to identify ecotoxicological effects of surface waters, and can be extremely useful, especially in cases where the biotic indices are difficult to establish, such as reservoirs.


Assuntos
Bioensaio , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Animais , Monitoramento Biológico , Daphnia/efeitos dos fármacos , Ecossistema , Ecotoxicologia , Europa (Continente) , Padrões de Referência , Estações do Ano , Qualidade da Água
2.
Ecotoxicol Environ Saf ; 208: 111583, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396106

RESUMO

To assess the ecological potential (EP), the Water Framework Directive (WFD) uses specific parameters but ignores ecosystem functioning and individual/subindividual biological responses. The heavily modified water bodies (reservoirs) are strongly influenced by human activities that promote their imbalance, with a loss or compromise the biodiversity and the functioning of these ecosystems. This work aims to determinate the EP according physical, chemical and biological parameters of WFD and evaluate the functionality and sensitivity of ecotoxicological tools in the evaluation of water quality of Aguieira reservoir. Four sampling sites were defined in Aguieira reservoir and sampling was conducted in autumn 2018, spring and autumn 2019. WFD showed overall that Aguieira reservoir presented moderate EP. The autumn samples and the two reservoir upstream sites had the worst classification. These results were complemented by a set of ecotoxicological assays (growth inhibition of Raphidocelis subcapitata and Spirodela polyrhiza, and feeding rate of Daphnia longispina) using three natural water treatments. R. subcapitata was the most sensitive species, indicating the presence of a risk that is not detected by chemical analysis, nor by organisms of different trophic levels. D. longispina only showed sensitivity in A3 and A4 in autumn, however this results was difficult to interpret since no reason can be observed to respond the F1 lower feeding rate observed in almost sites. S. polyrhiza, as well as the total chlorophyll, lipid peroxidation, and proline content did not show sensitivity, since no discrimination among the water treatments were recorded. The relevance of bioassays is associated with the fact that an integrated response to a complex mixture can be obtained, which can contain more substances than the measured ones. Thus, we may conclude that WFD are insufficient to draw conclusions about water quality, and the growth inhibition of Raphidocelis subcapitata assay is an important parameter to complement the WFD. In addition, species of different trophic levels are recommended for ecotoxicological analyses due to differences in species sensitivities.


Assuntos
Ecotoxicologia , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Animais , Bioensaio , Daphnia , Ecossistema , Política Ambiental , Humanos , Estações do Ano , Água/análise , Poluentes Químicos da Água/toxicidade , Qualidade da Água/normas
3.
Ecotoxicol Environ Saf ; 172: 348-355, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30731265

RESUMO

Predictions of the International Panel for Climate Changes on sea level rise foresee that the number of coastal regions impacted with salinization will increase in a near future. The present work intended to evaluate the sensitivity to salinization of two freshwater vertebrate species (the frog Pelophylax perezi and the fish Lepomis gibbosus) and their ability to acclimate to this stressor. For this, three specific objectives were targeted: (i) to assess if NaCl may be used as a safe surrogate for risk assessment of seawater (SW) intrusion for freshwater vertebrates; (ii) to evaluate the sensitivity of two freshwater vertebrate models to increased salinity (both due to NaCl or SW); (iii) to determine the capacity of the studied species to acclimate to low levels of salinization. To assess specific objectives (i) and (ii), organisms were exposed to serial concentrations of NaCl or SW dilutions. To assess the capacity of acclimation of both species to salinization, organisms were exposed to low serial concentrations of NaCl during the embryonic development or for a period of two months, respectively, and their sensitivity to NaCl was re-evaluated after this period. Results showed that fish juveniles were more tolerant (96-h LC50 of 21.3 mS cm-1 for NaCl and 23.6 mS cm-1 for SW) than frog embryos (96-h LC50 of 10.7 mS cm-1 for NaCl and 10.7 mS cm-1 for SW) and tadpoles (96-h LC50 of 19.4 mS cm-1 for NaCl and 8.72 mS cm-1 for SW). The fish was able to cope with conductivities of almost one third of SW conductivity, while effect conductivities computed for the amphibian were much lower than SW conductivity (≈ 52 mS cm-1). The two-fold difference between the sensitivity of the two tested species reinforces the idea that ecological risk assessment for amphibians based on fish toxicity data may underestimate the risk to the former. Acclimation to low levels of salinity caused an increase in tolerance to salinization in P. perezi tadpoles but not in fish.


Assuntos
Aclimatação , Perciformes/fisiologia , Ranidae/fisiologia , Salinidade , Tolerância ao Sal , Animais , Água Doce/química , Larva/fisiologia , Água do Mar/química , Cloreto de Sódio/análise , Estresse Fisiológico
4.
Antonie Van Leeuwenhoek ; 111(6): 825-840, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29222603

RESUMO

The nutritional quality of daphnids diet can influence their growth, reproduction and survival. In aquatic ecosystems, bacteria can contribute significantly to Daphnia diet by supporting, for instances, their high needs for phosphorus. The laboratory feeding of the model organisms Daphnia spp. is algal based, but should be improved to allow their better performance. The aim of this study was to evaluate the potential of two planctomycetes, Gemmata obscuriglobus and Rhodopirellula rubra, from exponential and stationary growth phases as alternative or supplementary food source for Daphnia magna. The actinobacterium Arthrobacter sp. was used for comparison. The feeding with only bacteria showed the inefficacy of both planctomycetes and actinobacteria as the only food source. However, when used in supplement to Raphidocelis subcapitata, a decrease in the age of first reproduction, a significant increase in reproductive output, in somatic growth and in rate of population increase was found for the highest cell densities of bacteria tested. The typical pink coloration of these bacteria present in daphnids body and eggs confirmed bacterial absorption and metabolization of their pigment. Planctomycetes yielded better results than the actinobacteria Arthrobacter but G. obscuriglobus that possesses sterols did not induce a better performance comparatively to R. rubra. No relation could be established between the feeding treatments that allowed improvement of Daphnia performance and the different kind of Daphnia' Fatty Acid Methyl Esters. The use of sonication to separate planctomycetal cells before feeding the daphnids proved to be efficient. We confirmed that R. subcapitata supplemented by bacteria allows a better growth performance of D. magna.


Assuntos
Daphnia , Alimentos , Animais , Arthrobacter , Clorófitas , Planctomycetales
5.
Ecotoxicol Environ Saf ; 164: 100-108, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30098505

RESUMO

Oxytetracycline (OTC) is a tetracycline antibiotic, widely used in human and veterinary medicines, including in aquaculture. Given this use, OTC has been detected in different aquatic environments. Some recent works have demonstrated unintentional biological activity of OTC in non-target aquatic organisms. This study investigated the acute and chronic effects of OTC on the physiology of the fish species Oncorhynchus mykiss (rainbow trout), namely through the quantification of the activity of enzymes involved in different biochemical pathways, such as detoxification (phase II - glutathione S-transferases - GSTs, uridine-diphosphate-glucuronosyltransferases - UGTs), neurotransmission (acetylcholinesterase - AChE) and energy production (lactate dehydrogenase - LDH). The here-obtained data demonstrated the induction of GSTs activity in gills, and inhibition of AChE activity in eyes tissue, in chronically exposed organisms, as well as alterations in LDH activity following both exposures. Considering this set of results, we can infer that OTC exposure may have induced the glutathione pathway of detoxification in gills with the involvement of GSTs, or indirectly due to the metabolites that may have been produced. In turn, these metabolites may have interfered with the mechanism of neurotransmission, also causing physiological and biochemical disturbances in rainbow trout after OTC exposure, namely disturbances in energetic metabolism. In addition, it is important to stress that such occurrences took place at low, environmentally realistic levels of OTC, suggesting that organisms exposed in the wild may be putative targets of toxic effects by commonly used drugs such as antibiotics.


Assuntos
Antibacterianos/toxicidade , Exposição Ambiental/efeitos adversos , Oncorhynchus mykiss/metabolismo , Oxitetraciclina/toxicidade , Transmissão Sináptica/efeitos dos fármacos , Acetilcolinesterase/metabolismo , Animais , Biomarcadores , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Glucuronosiltransferase/metabolismo , Glutationa/metabolismo , Glutationa Transferase/metabolismo , L-Lactato Desidrogenase/metabolismo , Qualidade da Água
6.
Arch Environ Contam Toxicol ; 74(4): 616-626, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29368034

RESUMO

The assessment of transgenerational effects should be incorporated in standard chronic toxicity protocols for the sake of a realistic extrapolation of contaminant effects to the population level. We propose a simple add-on to the standard 21-day chronic Daphnia magna assay, allowing the assessment of the reproductive performance of the offspring (F1 generation) born from the first clutch of the parental (F0) generation. The extended generational assay was performed simultaneously with the standard reproduction assay. With this design, we evaluated the lethal, reproductive, and transgenerational effects of four widespread and extensively used substances: a biocide/anti-fouling (copper sulphate), an industrial oxidizing agent (potassium dichromate), a pharmaceutical (paracetamol), and a quaternary ammonium compound (benzalkonium chloride). Benzalkonium chloride was the most toxic in terms of lethality, whereas paracetamol, copper sulphate, and potassium dichromate caused deleterious effects in the reproductive performance of exposed D. magna. Adverse effects in the fitness of the daughter (F1) generation were observed in the case of maternal exposure to paracetamol and copper sulphate, although they were not very pronounced. These findings highlight the usefulness of our approach and reinforce the view-shared by other authors-of the need for a generalised formal assessment of the transgenerational effects of pollutants.


Assuntos
Daphnia/efeitos dos fármacos , Ecotoxicologia/métodos , Poluentes Químicos da Água/toxicidade , Acetaminofen/toxicidade , Animais , Compostos de Benzalcônio/toxicidade , Sulfato de Cobre/toxicidade , Daphnia/fisiologia , Feminino , Masculino , Exposição Materna , Dicromato de Potássio/toxicidade , Reprodução/efeitos dos fármacos , Testes de Toxicidade Crônica/métodos
7.
Water Sci Technol ; 2017(3): 835-844, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30016301

RESUMO

Antibiotics (e.g. ciprofloxacin) have been detected in surface water and groundwater for several decades. In order to understand the potential impact of the continuous exposure of aquatic organisms to ciprofloxacin, a chronic assay was carried out with Daphnia magna. This approach allowed evaluation of the effects of ciprofloxacin on life-history and sub-individual parameters (antioxidant status and metabolic response: activities of catalase and glutathione S-transferases - GSTs; peroxidative damage; thiobarbituric acid reactive substances and genotoxic effects (genetic damage index, measured by the comet assay). Life-history parameters of D. magna showed no significant effects after ciprofloxacin exposure. Concerning oxidative stress and metabolism parameters, no significant alterations were reported for catalase and GSTs activities. However, a dual response was observed, with a significant decrease in lipid peroxidation levels at low ciprofloxacin concentrations (<0.013 mg/L), while a significant increase was verified at high ciprofloxacin concentrations (0.078 mg/L). The genotoxicity assay detected a significant increase in genetic damage index up to 0.013 mg/L of ciprofloxacin. The here-tested ciprofloxacin concentrations, which are ecologically relevant, did not cause significant impacts concerning the life-history parameters of D. magna; however, at the same levels of ciprofloxacin an oxidative stress and genotoxic damage scenarios were recorded.


Assuntos
Ciprofloxacina/toxicidade , Daphnia/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Antibacterianos/química , Antibacterianos/toxicidade , Antioxidantes , Catalase , Ciprofloxacina/química , Ensaio Cometa , Dano ao DNA , Daphnia/genética , Glutationa Transferase , Peroxidação de Lipídeos , Mutação , Estresse Oxidativo , Poluentes Químicos da Água/química
8.
Biochim Biophys Acta Mol Basis Dis ; 1863(3): 764-769, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28057587

RESUMO

Several hypotheses have been raised about the dual role of histamine in neurological disorders, and evidences have shown its crucial involvement in the modulation of microglia-mediated neuroinflammation. Previously, we reported that the administration of histamine induces a deleterious effect by promoting a pro-inflammatory phenotype on microglia that in turn compromises dopaminergic neuronal survival. Contrary, under lipopolysaccharide challenge, histamine inhibits the injurious effect of microglia-mediated inflammation, protecting dopaminergic neurons, suggesting that the modulation of microglial activity is dependent on the environmental context. Thus, histamine and/or histamine receptor agonists may serve to develop new therapeutic approaches to overcome neurodegenerative disorders.


Assuntos
Neurônios Dopaminérgicos/imunologia , Histamina/imunologia , Inflamação/imunologia , Microglia/imunologia , Doenças Neurodegenerativas/imunologia , Animais , Neurônios Dopaminérgicos/patologia , Humanos , Inflamação/patologia , Lipopolissacarídeos/imunologia , Microglia/patologia , Doenças Neurodegenerativas/patologia , Doença de Parkinson/imunologia , Doença de Parkinson/patologia
9.
Haemophilia ; 23(5): 682-688, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28440005

RESUMO

INTRODUCTION: Although the regular replacement of clotting factor concentrates (prophylaxis) has been well established as the standard of care for severe haemophilia, the high cost of factor concentrates has limited access to prophylaxis in countries with under-developed or developing economies. AIMS: We studied the health gap that could be addressed by providing unlimited access to clotting factor concentrates with implementation of long-term prophylaxis initiated from an early age in life. METHODS: We performed a cross-sectional study of a random, representative sample of boys with moderate and severe haemophilia at three haemophilia treatment centres in Sao Paulo, Brazil, and one centre in Toronto, Canada. RESULTS: Canadian subjects were more often treated with prophylaxis, and began treatment at an earlier age. Fewer Canadian subjects had bleeds within the preceding 6 months (19 vs. 34, P = 0.003). Canadian subjects had lower (better) Pettersson radiographic scores (1.5 vs. 6.0, P = 0.0016), lower (better) Hemophilia Joint Health Scores (5.5 vs. 10.5, P = 0.0038), higher (better) Activity Scale for Kids scores (96.6 vs. 92.0, P = 0.033), more time spent in vigorous activity, and higher (better) social participation scores. CONCLUSIONS: Our findings suggest that increasing access to clotting factor concentrates for young boys with severe haemophilia is a global imperative.


Assuntos
Efeitos Psicossociais da Doença , Países em Desenvolvimento , Recursos em Saúde , Hemofilia A/epidemiologia , Adolescente , Brasil/epidemiologia , Canadá/epidemiologia , Criança , Estudos Transversais , Indicadores Básicos de Saúde , Hemofilia A/diagnóstico , Hemofilia A/terapia , Humanos , Masculino , Qualidade de Vida , Índice de Gravidade de Doença
10.
Haemophilia ; 22(6): 894-897, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27456858

RESUMO

INTRODUCTION: It is essential to assess the health-related quality of life outcomes of boys with haemophilia in Brazil. The Canadian Haemophilia Outcomes-Kids Life Assessment Tool (CHO-KLAT) was recently adapted for this population. AIM: To test the construct validity of the Portuguese version of the CHO-KLAT. METHODS: We recruited 50 boys, with moderate [factor VIII (FVIII) level 1-5%] or severe (FVIII level <1%) haemophilia, to participate in a descriptive study to establish a baseline understanding of the current status of boys with haemophilia in Brazil. All boys were required to complete the Brazilian CHO-KLAT and Brazilian Pediatric Quality of Life Inventory (PedsQL) by self-report. We examined the correlation between the CHO-KLAT and PedsQL scores to establish the construct validity of the Brazilian version of the CHO-KLAT. RESULTS: We obtained CHO-KLAT and PedsQL data from 35 boys with severe haemophilia and 15 with moderate haemophilia. They ranged in age from 7.3 to 18.0 years, with a mean of 13.0 years. They reported a mean CHO-KLAT score of 72.3 (range = 44.1-93.9). The mean PedsQL score was 79.9 (range = 45.7-96.7), with physical health (mean of 83.9) being better than psychosocial health (77.8). The Pearson's correlation between CHO-KLAT and PedsQL was 0.47 respectively (P < 0.001). The CHO-KLAT had a moderate and inverse relationship with the degree to which they were bothered by their haemophilia (ρ = -0.53), while the PedsQL had a weaker relationship (ρ = -0.27). CONCLUSION: The results confirm the validity of the Portuguese version of the CHO-KLAT. This measure is now available for clinical trials in boys with haemophilia in Brazil.


Assuntos
Hemofilia A/tratamento farmacológico , Avaliação de Resultados em Cuidados de Saúde/métodos , Adolescente , Brasil , Criança , Humanos , Masculino , Qualidade de Vida
11.
Ecotoxicol Environ Saf ; 126: 1-13, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26707183

RESUMO

In the intertidal area, the interactions between anthropogenic contaminants and natural variations (biotic and abiotic factors) are poorly understood. Consequently, there is a great need for new assessment procedures to characterize the biological responses occurring in organisms from this extreme environment. Considering the intrinsic inter-individual variations among organisms from a single population, it is important to propose new methods that address this variability, by validating a sampling strategy in target groups of organisms, encompassing seasonal fluctuations. This strategy must however be less invasive than traditional methods, avoiding the mandatory sacrifice of the sampled organisms. By doing so, it is also possible to increase the ecological relevance of obtainable data, and contribute to minimize damage to endangered species. The main purpose of the present study was to assess the influence of seasonal variations in the responses elicited by anthropogenic compounds on a marine crustacean species, by using a biomarker-based approach. According to this purpose, the seasonal variations in key physiological responses (biomarkers) were investigated in the crustacean Pollicipes pollicipes from the Northern coast of Portugal. Biomarkers used for this purpose were the activity of the phase II biotransformation isoenzymes glutathione-S-transferases (GSTs), the activity of cholinesterases (ChEs), and the levels of lipid peroxidation (TBARS). All biomarkers were quantified in distinct tissues (such as cirri, and peduncle) and haemolymph (a non-destructive source of biological samples). The glycogen content in peduncle tissue, and the variation in haemocyte number in haemolymph were also analyzed. Samples were collected monthly, during a year, in Lavadores, located in the proximity of an estuarine area (Douro River). The results showed a seasonal pattern in all tested biomarkers. The results also showed a significant increase in GSTs activities, and in peroxidative damage, especially during warmer months. The lowest ChEs values were recorded during the rainy season. The results also showed a similar pattern among all tested tissues, validating the proposed use of the haemolymph as a source tissue for non-lethal sampling strategy for biomarker determinations. Glycogen content was apparently related to the reproductive cycle, with lower values being observed in spring and summer. Total haemocyte count (THC) increased during summer months. The results pointed to an influence of natural variations in the levels of biomarkers in P. pollicipes, highly dependent upon abiotic factors, a factor that must be considered when interpreting biological responses elicited by anthropogenic contaminants from the marine coastal environment. The validation of haemolymph as a non-lethal source tissue for the quantification of biomarkers was successfully attained, opening the possibility of less invasive and almost unlimited sampling in a small number of organisms.


Assuntos
Monitoramento Ambiental/métodos , Thoracica/metabolismo , Poluentes Químicos da Água/metabolismo , Análise de Variância , Animais , Biomarcadores/metabolismo , Colinesterases/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos , Estresse Oxidativo , Portugal , Rios , Estações do Ano , Poluentes Químicos da Água/toxicidade
12.
Ecotoxicol Environ Saf ; 134P1: 64-71, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27588555

RESUMO

During the past century, the amount of chemicals released into water bodies has increased, with particular emphasis being attributed to xenobiotics with endocrine disruption properties and/or pro-oxidant effects. Among these, it is possible to identify a specific chemical class, alkylphenols, which are of widespread use, and include a variety of chemicals with multiple uses. Bisphenol A is an important chemical used in industrial production of plastics, and has been extensively described as an endocrine disruptor. Paracetamol is a pharmaceutical compound used in human medicine, known for its therapeutic action but also for its evident pro-oxidant features. Additionally, previous studies have suggested that paracetamol may also exert endocrine disruption. The main goal of this study was to assess the effects of both paracetamol and bisphenol A as endocrine disruptors, and as promoters of oxidative stress and damage, on the freshwater microcrustacean Daphnia magna. The obtained results showed that bisphenol A was capable of altering population traits of exposed organisms, by impairing molting. On the contrary, paracetamol was not causative of any significant change in this parameter, despite having caused extensive oxidative stress.

13.
Exp Appl Acarol ; 70(1): 79-88, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27394441

RESUMO

Ticks are ubiquitous arthropods and vectors of several pathogenic agents in animals and humans. Monitoring questing ticks is of great importance to ascertain the occurrence of pathogens and the potential vector species, offering an insight into the risk of disease transmission in a given area. In this study 428 host-seeking ticks, belonging to nine species of Ixodidae and collected from 17 of the 23 Portuguese mainland subregions, were screened for several tick-borne agents with veterinary relevance: Anaplasma marginale, Anaplasma ovis, Anaplasma centrale, Babesia spp., Coxiella burnetii and Theileria spp. Prevalence was assessed by PCR and amplified amplicons sequenced for validation of results. Twenty ticks, in a total of 428, were found positive: one Ixodes ventalloi for Theileria annulata and four Dermacentor marginatus, one Haemaphysalis punctata, five Ixodes ricinus, five I. ventalloi, and four Rhipicephalus sanguineus sensu lato for A. marginale. According to the reviewed literature, this is the first report of A. marginale and T. annulata detection in I. ventalloi. Furthermore, the amplification of A. marginale DNA in several tick species suggests a broad range for this agent in Portugal that might include other uncommon species as R. sanguineus s.l. This work provides new data towards a better understanding of tick-pathogen associations and also contributes to the surveillance of tick-borne agents in geographic areas with limited information.


Assuntos
Anaplasma marginale/isolamento & purificação , Ixodidae/microbiologia , Ixodidae/parasitologia , Theileria annulata/isolamento & purificação , Anaplasma marginale/genética , Animais , DNA Bacteriano/genética , DNA de Protozoário/genética , Feminino , Ixodidae/crescimento & desenvolvimento , Larva/microbiologia , Larva/parasitologia , Masculino , Ninfa/microbiologia , Ninfa/parasitologia , Portugal , RNA Ribossômico 18S/genética , Theileria annulata/genética
14.
Ecotoxicology ; 24(9): 1896-905, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26298705

RESUMO

Currently diverse biocidal agents can be used for distinct applications, such as personal hygiene, disinfection, antiparasitic activity, and antifouling effects. Zinc pyrithione is an organometallic biocide, with bactericidal, algicidal and fungicidal activities. It has been recently incorporated in antifouling formulas, such as paints, which prevent the establishment of a biofilm on surfaces exposed to the aquatic environment. It has also been used in cosmetics, such as anti-dandruff shampoos and soaps. Previously reported data has shown the presence of this substance in the aquatic compartment, a factor contributing to the potential exertion of toxic effects, and there is also evidence that photodegradation products of zinc pyrithione were involved in neurotoxic effects, namely by inhibiting cholinesterases in fish species. Additional evidence points to the involvement of zinc pyrithione in alterations of metal homeostasis and oxidative stress, in both aquatic organisms and human cell models. The present work assesses the potential ecotoxicity elicited by zinc pyrithione in the freshwater fish Gambusia holbrooki after an acute (96 h) exposure. The oxidative stress was assessed by the quantification of the activities of specific enzymes from the antioxidant defense system, such as catalase, and glutathione-S-transferases; and the extent of peroxidative damage was quantified by measuring the thiobarbituric acid reactive substances levels. Neurotoxicity was assessed through measurement of acetylcholinesterase activity; and a standardized method for the description and assessment of histological changes in liver and gills of was also used. Zinc pyrithione caused non-specific and reversible tissue alterations, both in liver and gills of exposed organisms. However, histopathological indices were not significantly different from the control group. In terms of oxidative stress biomarkers, none of the tested biomarkers indicated the occurrence of pro-oxidative effects, suggesting that the oxidative pathway is not the major toxicological outcome of exposure to zinc pyrithione.


Assuntos
Ciprinodontiformes/metabolismo , Compostos Organometálicos/toxicidade , Piridinas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Feminino , Masculino , Estresse Oxidativo/efeitos dos fármacos
15.
Genet Mol Res ; 14(3): 10001-6, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26345936

RESUMO

The folate metabolic pathway, which is involved in DNA synthesis and methylation, is associated with individual susceptibility to several diseases, including gastric tumors. In this study, we investigated four polymorphisms [thymidylate synthase enhancer region, single nucleotide polymorphism thymidylate synthase 5' (TS5'), TS3' untranslated region, and methylenetetrahydrofolate reductase (MTHFR) 677C> T] in 2 genes related to the folate pathway, TS and MTHFR, and their possible association with the risk gastric cancer development in a population from Pará state, Brazil. For the TS enhancer region, TS3' untranslated region, and single nucleotide polymorphism TS5' polymorphisms, no significant results were obtained. For the MTHFR 677C>T polymorphism, TT genotype carriers had a higher risk of developing tumors in the antrum (P = 0.19 vs CC and P = 0.02 vs CT) and intestine (odds ratio = 4.18, 95% confidence interval = 0.66-26.41; P = 0.252 vs CC and odds ratio = 2.25, 95% confidence interval = 0.32-15.75; P = 0.725 vs CT). Those carrying at least 1 T allele had an increased risk of lymph node metastasis (odds ratio = 3.00, 95% confidence interval = 0.88-10.12; P = 0.133). Our results suggest that polymorphisms in MTHFR affect the susceptibility to gastric tumors in the Brazilian population and may be a factor causing poor prognosis in such patients.


Assuntos
Predisposição Genética para Doença , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único , Neoplasias Gástricas/genética , Timidilato Sintase/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Brasil/epidemiologia , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Vigilância da População , Neoplasias Gástricas/epidemiologia
16.
Arch Environ Contam Toxicol ; 68(2): 371-81, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25475590

RESUMO

A large body of evidence was compiled in the recent decades showing a noteworthy increase in the detection of pharmaceutical drugs in aquatic ecosystems. Due to its ubiquitous presence, chemical nature, and practical purpose, this type of contaminant can exert toxic effects in nontarget organisms. Exposure to pharmaceutical drugs can result in adaptive alterations, such as changes in tissues, or in key homeostatic mechanisms, such as antioxidant mechanisms, biochemical/physiological pathways, and cellular damage. These alterations can be monitored to determine the impact of these compounds on exposed aquatic organisms. Among pharmaceutical drugs in the environment, antibiotics are particularly important because they include a variety of substances widely used in medical and veterinary practice, livestock production, and aquaculture. This wide use constitutes a decisive factor contributing for their frequent detection in the aquatic environment. Tetracyclines are the individual antibiotic subclass with the second highest frequency of detection in environmental matrices. The characterization of the potential ecotoxicological effects of tetracycline is a much-required task; to attain this objective, the present study assessed the acute toxic effects of tetracycline in the freshwater fish species Gambusia holbrooki by the determination of histological changes in the gills and liver, changes in antioxidant defense [glutathione S-transferase (GST), catalase (CAT), and lipoperoxidative damage] as well as potential neurotoxicity (acetylcholinesterase activity). The obtained results suggest the existence of a cause-and-effect relationship between the exposure to tetracycline and histological alterations (more specifically in gills) and enzymatic activity (particularly the enzyme CAT in liver and GST in gills) indicating that this compound can exert a pro-oxidative activity.


Assuntos
Antibacterianos/toxicidade , Tetraciclina/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Ciprinodontiformes/metabolismo , Água Doce/química , Glutationa Transferase/metabolismo
17.
Haemophilia ; 20(5): 644-50, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24589084

RESUMO

The Pro-FEIBA study reported health-related quality of life (HRQoL) improved following 6-month of Factor Eight Inhibitor Bypassing Activity (FEIBA) prophylaxis. This study investigates whether 12-month of FEIBA prophylaxis improved HRQoL in haemophilia patients with inhibitors. Thirty-six subjects in a 1-year prospective, randomized, open-label, parallel-design study were randomized to prophylaxis (85 ± 15 U kg(-1) every other day) or on-demand treatment. HRQoL was assessed at screening, 6 and 12-month termination using the EQ-5D, Haem-A-QoL, Haemo-QoL and a general pain visual analog scale (VAS). To evaluate changes, paired t-tests and criteria for minimally important differences were applied. Repeated measures regression tested the association between annualized bleeding rate (ABR) and physical HRQoL. At 6 and 12 months, prophylaxis subjects reported clinically meaningful improvement in EQ-5D index (mean improvement, 0.10 and 0.08, respectively) and both clinically meaningful and statistically significant improvements in EQ-VAS scores (16.9 and 15.7, respectively; P < 0.05) vs. baseline. General pain was significantly reduced during prophylaxis at each follow-up (mean improvement, 20.3 and 23.2, respectively; both P <0.05). At 12 months, prophylaxis subjects achieved significant improvements in Haem-A-QoL Total Score and in four domains: Physical Health, Feeling, View, and Work and School (all P < 0.05). No statistically significant changes, except for Haem-A-QoL Physical Health at 6 months, were observed with on-demand treatment. ABR was decreased by 72.5% with prophylaxis vs. on-demand treatment (P = 0.0003) and reduced ABR was associated with better physical HRQoL (P < 0.05). FEIBA prophylaxis significantly reduced ABR and improved HRQoL in inhibitor patients. Subjects with lower ABR reported better physical HRQoL.


Assuntos
Fatores de Coagulação Sanguínea/uso terapêutico , Coagulantes/administração & dosagem , Fator VIII/administração & dosagem , Nível de Saúde , Hemofilia A/tratamento farmacológico , Qualidade de Vida , Adolescente , Adulto , Criança , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Estudos Prospectivos , Análise de Regressão , Inquéritos e Questionários , Adulto Jovem
18.
Haemophilia ; 20(1): 65-72, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23910578

RESUMO

Factor replacement therapy for the treatment of moderate to severe haemophilia A and B can be complicated by the production of inhibitory alloantibodies to factor VIII (FVIII) or factor IX. Treatment with the nanofiltered anti-inhibitor coagulant complex, Factor Eight Inhibitor Bypassing Activity (FEIBA NF), is a key therapeutic option for controlling acute haemorrhages in patients with high-titre inhibitors or low-titre inhibitors refractory to replacement therapy. Given the high risk for morbidity and mortality in haemophilia patients with inhibitors to FVIII or FIX, we conducted this Phase 3 prospective study to evaluate whether prophylaxis with FEIBA NF is a safe and effective treatment option. Over a 1-year period, 17 subjects were treated prophylactically (85 ± 15 U kg(-1) every other day) while 19 subjects were treated on demand. The median (IQR) annualized bleeding rate (ABR) during prophylaxis was 7.9 (8.1), compared to 28.7 (32.3) during on-demand treatment, which amounts to a 72.5% reduction and a statistically significant difference in ABRs between arms (P = 0.0003). Three (17.6%) subjects (ITT) on prophylaxis experienced no bleeding episodes, whereas none treated on demand were bleeding episode-free. Total utilization of FEIBA NF for the treatment of bleeding episodes was significantly higher during on-demand therapy than prophylaxis (P = 0.0067). There were no differences in the rates of related adverse events between arms. This study demonstrates that FEIBA prophylaxis significantly reduces all types of bleeding compared with on-demand treatment, and the safety of prophylaxis is comparable to that of on-demand treatment.


Assuntos
Fatores de Coagulação Sanguínea/uso terapêutico , Fator IX/uso terapêutico , Fator VIII/uso terapêutico , Hemofilia A/tratamento farmacológico , Hemofilia B/tratamento farmacológico , Pré-Medicação , Adolescente , Adulto , Inibidores dos Fatores de Coagulação Sanguínea , Fatores de Coagulação Sanguínea/administração & dosagem , Fatores de Coagulação Sanguínea/efeitos adversos , Criança , Fator IX/administração & dosagem , Fator IX/efeitos adversos , Fator VIII/administração & dosagem , Fator VIII/efeitos adversos , Hemofilia A/sangue , Hemofilia A/complicações , Hemofilia B/sangue , Hemofilia B/complicações , Hemorragia/etiologia , Hemorragia/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Resultado do Tratamento , Adulto Jovem
19.
Arch Environ Contam Toxicol ; 66(3): 317-26, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24337668

RESUMO

The assessment of toxic effects caused by complex mixtures of contaminants in the marine environment requires previous validation of toxicological criteria, which may include biomarker end points with distinct biological meanings. This is the case of oxidative stress/phase II detoxification (glutathione-S-transferases activity), oxidative damage (thiobarbituric acid reactive substances), and neurotransmission (cholinesterase activity), which are likely to be affected after toxic insults by common marine pollutants. The main purpose of the present study was to assess potential biological alterations in the mollusk species Pollicipes pollicipes (gooseneck barnacle) caused by human contamination and seasonality, during a period of 1 year, in three different areas of the North Atlantic shore of Portugal. Our results indicate that fluctuations of the mentioned biomarkers were strongly related to seasonality, but they may also suffer influence by the already documented patterns of chemical contamination. Organisms collected in contaminated sampling sites (urban areas and oil refinery) showed greater levels of metabolic enzymes and increased levels of lipid peroxidation. These alterations were more evident during the summer, and, in some cases, spring months, suggesting an association between the presence of chemical stressors and temperature-dependent seasonal physiological fluctuations, which contribute to the modulation of the toxic response. In general terms, P. pollicipes was shown to be a promising organism in coastal biomonitoring programs, with an adequate sensitivity toward contamination and/or seasonal fluctuations. However, it is of the utmost importance to consider seasonal fluctuations in physiological parameters that modulate the toxic response. These factors can ultimately compromise the development and interpretation of data from marine biomonitoring programs if a thorough characterization of biological responses is not previously performed.


Assuntos
Monitoramento Ambiental/métodos , Thoracica/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Biomarcadores/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos , Estresse Oxidativo , Portugal , Poluentes Químicos da Água/toxicidade
20.
Environ Toxicol Pharmacol ; 99: 104114, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37001686

RESUMO

Biopesticides are natural compounds considered more safe and sustainable for the environment. However, it is also important to evaluate the potential risk in non-target organisms. Pyrethrum extract (PE) is a biopesticide, widely used for agriculture, veterinary, and aquaculture. This work aimed to evaluate acute (0.6 - 40.0 µg/L; 96 h; E(L)C50 toxicity) and sub-chronic (0.7 - 1.1 µg/L; 10 d; life-history parameters) effects of PE on Daphnia magna. Moreover, a biomarkers approach using antioxidant and biotransformation capacity, lipid peroxidation (LPO), neurotoxicity, and energy reserves content were evaluated. Acute effects (mortality, changes in swimming behavior, oxidative stress, lipid peroxidation, neurotoxicity) were recorded with the increase in PE concentration. Sub-chronic assay showed an increase in energy reserves content, antioxidant parameters, and LPO demonstrating that PE unbalances oxidative metabolism. This study can conclude that PE potentiates toxic effects in D. magna and demonstrates the vulnerability of a non-target organism to PE that is considered environmentally safe.


Assuntos
Chrysanthemum cinerariifolium , Piretrinas , Poluentes Químicos da Água , Animais , Antioxidantes/farmacologia , Agentes de Controle Biológico/metabolismo , Agentes de Controle Biológico/farmacologia , Daphnia , Chrysanthemum cinerariifolium/metabolismo , Estresse Oxidativo , Piretrinas/toxicidade , Piretrinas/metabolismo , Poluentes Químicos da Água/metabolismo
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