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1.
Ecotoxicol Environ Saf ; 275: 116244, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38537480

RESUMO

A risk assessment on the aquatic toxicity of the plant biostimulant strigolactone mimic (2-(4-methyl-5-oxo-2,5-dihydro-furan-2-yloxy)-benzo[de]isoquinoline-1,3-dione (SL-6) was performed using a suite of standardised bioassays representing different trophic groups and acute and chronic endpoints. In freshwater, three trophic groups of algae, crustacea and fish were used. Whilst in seawater, algae (unicellular and macroalgae), Crustacea and Mollusca were employed. In addition, the genotoxicity of SL-6 was determined with the comet assessment performed on unicellular marine algae, oysters, and fish embryos. This was the first time ecotoxicity tests have been performed on SL-6. In freshwater, the lowest LOEC was measured in the unicellular algae at 0.31 mg/L SL-6. Although, similar LOEC values were found for embryo malformations and impacts on hatching rate in zebrafish (LOEC 0.31-0.33 mg/L). Consistent malformations of pericardial and yolk sac oedemas were identified in the zebrafish embryos at 0.31 mg/L. In marine species, the lowest LOEC was found for both Tisbe battagliai mortality and microalgae growth at an SL-6 concentration of 1.0 mg/L. Significant genotoxicity was observed above control levels at 0.0031 mg/L SL-6 in the unicellular algae and 0.001 mg/L SL-6 in the oyster and zebrafish larvae. When applying the simple risk assessment, based on the lowest NOECs and appropriate assessment factors, the calculated predicted no effect concentration (PNEC), for the ecotoxicity and the genotoxicity tests were 1.0 µg/L and 0.01 µg/L respectively.


Assuntos
Compostos Heterocíclicos com 3 Anéis , Lactonas , Poluentes Químicos da Água , Peixe-Zebra , Animais , Larva , Crustáceos , Testes de Mutagenicidade , Poluentes Químicos da Água/toxicidade
2.
Retina ; 44(4): 700-706, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38109709

RESUMO

PURPOSE: To determine the degree of central microvascular closure using optical coherence tomography angiography in eyes of patients with type 2 diabetes with visible lesions only in the central retina or only in the periphery. METHODS: Cross-sectional study. All 127 eyes underwent ultra-widefield fundus photography 200° examinations with OPTOS California (Optos, Dunfermline, United Kingdom) and Cirrus Angioplex optical coherence tomography angiography 3 × 3 mm acquisitions (ZEISS, Dublin, CA). RESULTS: Twenty-five eyes showed visible lesions only in the central retina, 57 only in the peripheral retina, and 45 presented visible lesions in entire retina. The group with visible lesions only in the periphery showed definite closure in the superficial capillary plexus in 49% of the eyes, whereas the group with visible lesions only in the central seven-early treatment diabetic retinopathy study fields area showed a definite closure in 64%. CONCLUSION: Central capillary closure is already present in the initial stages of diabetic retinopathy even when lesions are only visible in the peripheral retina. Capillary closure in the superficial capillary plexus is three times more frequent than in the deep capillary plexus, demonstrating earlier closure of the superficial capillary plexus. Eyes with visible lesions only in the periphery show a milder form of retinopathy.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Humanos , Estudos Transversais , Vasos Retinianos/patologia , Angiofluoresceinografia/métodos , Retina/patologia , Tomografia de Coerência Óptica/métodos
3.
Ophthalmic Res ; 66(1): 1327-1334, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37820590

RESUMO

INTRODUCTION: The aim of the study was to identify retinal microvascular changes using optical coherence tomography angiography (OCTA) in type 2 diabetes (T2D) patients with preclinical retinopathy identified by ultra-widefield fundus photography (UWF-FP). METHODS: This is a cross-sectional observational study. All patients underwent UWF-FP 200° examinations with OPTOS California (Optos, Dunfermline, UK) and Cirrus AngioPlex® spectral-domain (SD)-OCTA 3 × 3 mm acquisitions (ZEISS, Dublin, CA, USA). The absence of visible lesions was identified using UWF-FP. RESULTS: One hundred and ninety three eyes of individuals with T2D with no visible lesions in the fundus and identified in a screening setting were included in the study. Skeletonized vessel density (SVD), perfusion density (PD), and areas of capillary nonperfusion (CNP) values on SD-OCTA were significantly decreased when compared with healthy population (p < 0.001). SVD and CNP values of the superficial capillary plexus (SCP) were more frequently decreased (35% and 45%, respectively) than SVD values of the deep capillary plexus (DCP) (9% and 15%, respectively), demonstrating that diabetic microvascular changes occur earlier in the SCP than in the DCP. The ischemic phenotype, identified by a definite decrease in SVD or CNP in the SCP may, therefore, be identified in the preclinical stage of diabetic retinal disease. CONCLUSIONS: Retinal capillary nonperfusion detected by OCTA metrics of SVD and CNP can be identified in the central retina in eyes with T2D before development of visible lesions in the retina. Our findings confirm the relevance of OCTA to identify macular microvascular changes in the initial stages of diabetic retinopathy, allowing the identification of its ischemic phenotype very early in the disease process.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Humanos , Retinopatia Diabética/patologia , Diabetes Mellitus Tipo 2/complicações , Vasos Retinianos/patologia , Estudos Transversais , Angiofluoresceinografia/métodos , Retina , Isquemia/diagnóstico , Tomografia de Coerência Óptica/métodos
4.
Leiria; s.n; 27 Jul 2023.
Tese em Português | BDENF - Enfermagem | ID: biblio-1525646

RESUMO

O Inverno demográfico é hoje uma realidade portuguesa, conjugado com o aumento da esperança média de vida existe uma área de atuação bastante abrangente para o trabalho do Enfermeiro Especialista em Enfermagem de Saúde Comunitária: área de Enfermagem de Saúde Comunitária e de Saúde Pública. O trabalho descrito neste relatório serve para a aprendizagem e enraizamento das competências comuns e específicas descritas no colégio da especialidade de Enfermagem de Saúde Comunitária e de Saúde Pública colmatando com a pretensão da obtenção do grau de Mestre e Especialista. Para o alicerce das intervenções de Enfermagem seleciono o Modelo de Promoção da saúde de Nola Pender a nível da prevenção e promoção da saúde dos indivíduos. Os focos e diagnósticos dessas intervenções estão de acordo com a Classificação Internacional para a Prática de Enfermagem e em consonância com a parametrização nacional. Descrevo as competências comuns e específicas em interligação com os Padrões de Qualidade de Enfermagem. Apresento o Planeamento em Saúde do projeto de intervenção "Queda off ­ Capacitação do cuidador formal na prevenção de quedas". Para que o trabalho tenha evidência para a prática de cuidados de Enfermagem realizada uma revisão sistemática da literatura. Uma das principais conclusões é que as intervenções a nível da prevenção e promoção da saúde podem ter ganhos em saúde para os indivíduos pertencentes à comunidade alvo, mas indiretamente existem ganhos, devido a ausência de gastos nos cuidados diferenciados promovendo assim uma gestão em saúde mais eficiente. Uma sugestão futura seria a capacitação de infraestruturas similares onde se verificam inconformidades major na aplicação de algumas escalas, com o intuito de apoio, na fase inicial da equipa de Enfermagem, mediante as orientações do PNS e dos programas em execução perspetivando sempre que esta se torne capaz de continuar a sua capacitação no futuro, tornando-a assim empoderada.


The demographic winter is today a Portuguese reality, combined with the increase in average life expectancy there is a very broad area of activity for the work of the Nurse Specialist in Community Health Nursing: the area of Community Health and Public Health Nursing. The work described in this report serves to learn and ingrain common and specific skills described in the College of Community Health and Public Health Nursing, fulfilling the aim of obtaining a Master's and Specialist degree. For the foundation of Nursing interventions, I selected Nola Pender's Health Promotion Model in terms of prevention and promotion of individuals' health. The focuses and diagnoses of these interventions are in accordance with the International Classification for Nursing Practice and in line with national parameters. I describe the common and specific competencies in connection with the Nursing Quality Standards. I present the Health Planning of the intervention project "Falls off ­ Training formal caregivers in preventing falls". In order for the work to have evidence for the practice of Nursing care, a systematic review of the literature was carried out. One of the main conclusions is that interventions in terms of prevention and health promotion can have health gains for individuals belonging to the target community, but indirectly there are gains, due to the absence of spending on differentiated care, thus promoting more efficient health management. . A future suggestion would be the training of similar infrastructures where there are major nonconformities in the application of some scales, with the aim of supporting, in the initial phase of the Nursing team, through the guidelines of the PNS and the programs in execution, with the prospect of always becoming capable of continuing her training in the future, thus making her empowered.


Assuntos
Idoso , Acidentes por Quedas , Idoso , Enfermagem em Saúde Comunitária , Envelhecimento Saudável , Enfermagem Geriátrica , Cuidados de Enfermagem
5.
J Hazard Mater ; 458: 131810, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37336109

RESUMO

The current study investigated the chemical complexity of fifty plastic (36) and elastomer/rubber (14) methanol extracts from consumer products, focusing on the association with toxicity in two screening assays (bacteria luminescence and marine microalgae). The chemical composition varied considerably between the products and polymers. The most complex sample (car tire rubber) contained 2456 chemical features and the least complex (disposable water bottle) only 39 features, with a median of 386 features across all products. Individual extract toxicity also varied significantly across the products and polymers, with the two toxicity assays showing comparable results in terms of defining low and high toxicity extracts, and correlation between medium toxicity extracts. Chemical complexity and abundance both correlated with toxicity in both assays. However, there were strong differences in toxicity between plastic and elastomer extracts. Overall, 86-93 % of the 14 elastomer extracts and only 33-36 % of other polymer extracts (n = 36) were more toxic than the median. A range of compounds were tentatively identified across the sample set, with several concerning compounds being identified, mostly in the elastomers. While the current focus on plastic chemicals is towards thermoplastics, we show that elastomers may be of more concern from an environmental and human health perspective.


Assuntos
Plásticos , Borracha , Humanos , Compostos Orgânicos , Polímeros , Elastômeros , Bactérias
6.
Br J Ophthalmol ; 107(8): 1132-1138, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-35277395

RESUMO

BACKGROUND/AIMS: Retinopathy of prematurity (ROP) is currently diagnosed through repeated eye examinations to find the low percentage of infants that fulfil treatment criteria to reduce vision loss. A prediction model for severe ROP requiring treatment that might sensitively and specifically identify infants that develop severe ROP, DIGIROP-Birth, was developed using birth characteristics. DIGIROP-Screen additionally incorporates first signs of ROP in different models over time. The aim was to validate DIGIROP-Birth, DIGIROP-Screen and their decision support tool on a contemporary Swedish cohort. METHODS: Data were retrieved from the Swedish national registry for ROP (2018-2019) and two Swedish regions (2020), including 1082 infants born at gestational age (GA) 24 to <31 weeks. The predictors were GA at birth, sex, standardised birth weight and age at the first sign of ROP. The outcome was ROP treatment. Sensitivity, specificity and area under the receiver operating characteristic curve (AUC) with 95% CI were described. RESULTS: For DIGIROP-Birth, the AUC was 0.93 (95% CI 0.90 to 0.95); for DIGIROP-Screen, it ranged between 0.93 and 0.97. The specificity was 49.9% (95% CI 46.7 to 53.0) and the sensitivity was 96.5% (95% CI 87.9 to 99.6) for the tool applied at birth. For DIGIROP-Screen, the cumulative specificity ranged between 50.0% and 78.7%. One infant with Beckwith-Wiedemann syndrome who fulfilled criteria for ROP treatment and had no missed/incomplete examinations was incorrectly flagged as not needing screening. CONCLUSIONS: DIGIROP-Birth and DIGIROP-Screen showed high predictive ability in a contemporary Swedish cohort. At birth, 50% of the infants born at 24 to <31 weeks of gestation were predicted to have low risk of severe ROP and could potentially be released from ROP screening examinations. All routinely screened treated infants, excluding those screened for clinical indications of severe illness, were correctly flagged as needing ROP screening.


Assuntos
Retinopatia da Prematuridade , Recém-Nascido , Lactente , Humanos , Retinopatia da Prematuridade/diagnóstico , Retinopatia da Prematuridade/epidemiologia , Retinopatia da Prematuridade/terapia , Suécia/epidemiologia , Fatores de Risco , Recém-Nascido Prematuro , Peso ao Nascer , Idade Gestacional , Triagem Neonatal , Estudos Retrospectivos
7.
Front Cell Infect Microbiol ; 11: 678568, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34327150

RESUMO

Host innate immunity is fundamental to the resistance against Candida albicans and Candida glabrata infection, two of the most important agents contributing to human fungal infections. Phagocytic cells, such as neutrophils, constitute the first line of host defense mechanisms, and the release of neutrophil extracellular traps (NETs) represent an important strategy to immobilize and to kill invading microorganisms, arresting the establishment of infection. The purinergic system operates an important role in the homeostasis of immunity and inflammation, and ectophosphatase and ectonucleotidase activities are recognized as essential for survival strategies and infectious potential of several pathogens. The expression and unique activity of a 3'-nucleotidase/nuclease (3'NT/NU), able to hydrolyze not only AMP but also nucleic acids, has been considered as part of a possible mechanism of microbes to escape from NETs. The aim of the present study was to evaluate if yeasts escape from the NET-mediated killing through their 3'NT/NU enzymatic activity contributing to NET-hydrolysis. After demonstrating the presence of 3'NT/NU activity in C. albicans, C. glabrata, and Saccharomyces cerevisiae, we show that, during neutrophils-Candida interaction, when NETs formation and release are triggered, NETs digestion occurs and this process of NETs disruption promoted by yeast cells was prevented by ammonium tetrathiomolybdate (TTM), a 3'NT/NU inhibitor. In conclusion, although the exact nature and specificity of yeasts ectonucleotidases are not completely unraveled, we highlight the importance of these enzymes in the context of infection, helping yeasts to overcome host defenses, whereby C. albicans and C. glabrata can escape NET-mediate killing through their 3'NT/NU activity.


Assuntos
Armadilhas Extracelulares , Candida , Candida albicans , Humanos , Neutrófilos , Nucleotídeos
8.
Ecotoxicol Environ Saf ; 222: 112553, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34325198

RESUMO

Pharmaceuticals are produced to inflict a specific physiological response in organisms. However, as only partially metabolized after administration, these types of compounds can also originate harmful side effects to non-target organisms. Additionally, there is still a lack of knowledge on the toxicological effects of legacy pharmaceuticals such as the antibiotic azithromycin. This macrolide occurs at high concentrations in the aquatic environment and can constitute a threat to aquatic organisms that are at the basis of the aquatic food chain, namely microalgae. This study established a high-throughput methodology to study the toxicity of azithromycin to the freshwater microalga Raphidocelis subcapitata. Flow cytometry and pulse amplitude modulated (PAM) fluorometry were used as screening tools. General toxicity was shown by effects in growth rate, cell size, cell complexity, cell viability and cell cycle. More specific outcomes were indicated by the analysis of mitochondrial and cytoplasmatic membrane potentials, DNA content, formation of ROS and LPO, natural pigments content and photosystem II performance. The specific mode of action (MoA) of azithromycin to crucial components of microalgae cells was revealed. Azithromycin had a negative impact on the regulation of energy dissipation at the PSII centers, along with an insufficient protection by the regulatory mechanisms leading to photodamage. The blockage of photosynthetic electrons led to ROS formation and consequent oxidative damage, affecting membranes and DNA. Overall, the used methodology exhibited its high potential for detecting the toxic MoA of compounds in microalgae and should be considered for future risk assessment of pharmaceuticals.


Assuntos
Clorofíceas , Microalgas , Poluentes Químicos da Água , Azitromicina/toxicidade , Água Doce , Poluentes Químicos da Água/toxicidade
9.
Rev. bras. oftalmol ; 80(3): e0002, 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1251329

RESUMO

ABSTRACT Conjunctival concretions are single or clustered lesions frequently found on the palpebral conjunctiva. They are commonly present in older individuals, despite being rarely symptomatic. This case report describes an 83-year-old man with multiple conjunctival concretions, which were surgically treated. The patient was symptomatic on presentation and did not respond to conservative treatment. For this reason, a surgical approach was considered. After wide excision of the conjunctival lesions, a piece of amniotic membrane was fitted using fibrin glue. During follow-up, a markedly improvement in patient's symptoms was observed, along with nearly complete absence of conjunctival concretions. This is the first case report addressing extensive conjunctival concretions with a surgical approach using amniotic membrane. The authors conceived the technique described after noticing the limited clinical options in the literature. This technique was easily performed and achieved satisfactory results.


RESUMO As concreções conjuntivais representam lesões amareladas, simples ou múltiplas, frequentemente encontradas na conjuntiva palpebral. São mais prevalentes em idades avançadas e raramente sintomáticas. Este relato de caso descreve o quadro clínico de um paciente de 83 anos com múltiplas concreções conjuntivais, cirurgicamente tratadas. Por se tratar de um paciente sintomático com resposta insuficiente ao tratamento conservador, foi considerada a abordagem cirúrgica. Após remoção das lesões, foi aplicado um enxerto de membrana amniótica, adaptado com cola de fibrina. No acompanhamento pós-operatório, verificou-se melhoria significativa dos sintomas, com desaparecimento quase total das concreções conjuntivais. Este é o primeiro caso que descreve uma abordagem cirúrgica com utilização de membrana amniótica na resolução desse tipo de lesões. A técnica, de fácil execução e com resultados muito favoráveis, foi desenvolvida pelos autores após constatarem a escassez de alternativas na literatura.


Assuntos
Humanos , Masculino , Idoso de 80 Anos ou mais , Adesivo Tecidual de Fibrina/uso terapêutico , Doenças da Túnica Conjuntiva/cirurgia , Litíase/cirurgia , Âmnio/transplante
10.
Sci Total Environ ; 726: 138547, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32320882

RESUMO

Due to their small size, nanoplastics (NPLs) possess specific properties which can potentiate their toxicity towards aquatic organisms. As primary producers, microalgae are at the base of aquatic food chains, thus negative impacts of NPLs will likely lead to disturbances in ecosystem productivity. The majority of data available on the toxicity of NPLs is limited to polystyrene and green microalgae, leaving a significant lack of knowledge on impacts of other polymer types across different taxonomic groups. So, the main objective of this study was to evaluate the cell responses of the red microalgae Rhodomonas baltica to plain and carboxylated poly(methyl methacrylate) NPLs (PMMA and PMMA-COOH, 50 nm). Results showed different NPL behaviour in media over time, with PMMA forming micro-scale aggregates and PMMA-COOH maintaining its nominal size range. PMMA caused a higher impact in cellular and physiological parameters than PMMA-COOH, even though a decrease in algal growth was only seen for the later. Overall, PMMA caused a significant decrease in cell viability followed by an increase in cell size and complexity, overproduction of pigments, loss of membrane integrity, hyperpolarization of the mitochondrial membrane, increased production of ROS and LPO, decrease in DNA content and reduced photosynthetic capacity. Conversely, a decrease in algal growth for PMMA-COOH was connected to an impairment in cell cycle and consequent decrease in cell viability, metabolic activity and photosynthetic performance, with negligible effects in ROS formation and pigments content. This study provided a first insight into the mechanistic understanding of the toxic impacts of PMMA and PMMA-COOH NPLs in red microalgae. Results obtained suggest an interaction between both NPLs and R. baltica cell surface that is dependent on particle behaviour and surface chemistry. Future experiments focusing on the in-depth characterization of the mode of action of these particles are recommended.


Assuntos
Microalgas , Poluentes Químicos da Água , Ecossistema , Polimetil Metacrilato , Poliestirenos
11.
Int J Biol Macromol ; 157: 119-134, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32335118

RESUMO

Chitosan and hyaluronic acid are the most attractive natural polysaccharides used for tissue regeneration, herein innovative orthopedic coatings were constructed by dip-coating technique. Inspired by the tough nacre-like structure, multifunctional (MF) films were constructed using bioactive glass nanoparticles (BGNPs) as the inorganic phase and hyaluronic acid (HA) and chitosan (CHT) polymers as the organic phase. Polymeric (CTR) films were also built with both polysaccharides. Inspired by the marine mussel's adhesive proteins, it was the first time that multilayered coatings containing both HA and CHT catechol conjugates were combined with BGNPs. Both catechol-conjugates were successful synthesized and, particularly for HA, it was possible to achieve the double of the substitution degree varying the reaction time. Prior to the LbL build-up, viscosity and Zeta potential measurements of the polyelectrolytes were conducted. The in-situ LbL growth of the films was monitored by quartz crystal microbalance with dissipation monitoring. It was found that the combination of both catechol conjugates resulted in a more compact LbL structure. It was also shown that MF evidenced bioactivity, CTR presented an improved adhesion, and preliminary cellular tests confirmed the biomedical potential of these multilayered coatings being used in orthopedic implants.


Assuntos
Catecóis/química , Quitosana/química , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Vidro/química , Ácido Hialurônico/química , Nanopartículas/química , Adesividade , Regeneração Tecidual Guiada , Viscosidade
12.
Sci Total Environ ; 687: 827-838, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31412486

RESUMO

Microalgal toxicity tests using integrative endpoints as algal growth are regularly required to analyse the toxicity of potentially hazardous substances in the aquatic environment. However, these do not provide mechanistic information on the toxic mode of action by which contaminants may affect algae. Bottled waters can be used as a substitute for culturing media and should not impose any stress to the cultured organisms. However, certain chemical components can interfere with specific cell targets which are not revealed by general toxicity assays. The present study investigated the sensitivity of flow cytometry (FCM) to analyse sub-lethal effects of different bottled waters to the freshwater microalgae Raphidocelis subcapitata. Several endpoints were analysed including growth rate, natural pigments content, cell size, complexity, viability and cycle, Reactive Oxygen Species (ROS) formation, mitochondrial membrane potential and Lipid Peroxidation (LPO). Additionally, photosystem II (PSII) performance was analysed by PAM fluorometry, to provide further information on the absorption, distribution and use of energy in photosynthesis. Results indicated that the most sensitive endpoints were the oxidative stress related endpoints ROS formation and LPO, pigment content, morphological endpoints as cell size, complexity and cycle, with growth rate being one of the least sensitive. Although being essential macronutrients for algal growth, the chemical elements Ca, Na, Mg, and NH4 were identified as being primarily responsible for the observed toxicological effects to exposed algae. The applied methodology proved to be of high throughput, simultaneously assembling information on morphological, biochemical, and physiological status of algal cells. FCM also showed potential to reveal mechanistic information on the toxic mode of action of the bottled waters before any effects on algal growth was observed. The used approach demonstrated its potential for being integrated into future microalgal toxicity bioassays for testing chemicals to improve the hazard information obtained from currently approved internationally accepted test guidelines.


Assuntos
Clorofíceas/efeitos dos fármacos , Testes de Toxicidade/métodos , Poluentes Químicos da Água/toxicidade , Biomarcadores , Monitoramento Ambiental/métodos , Citometria de Fluxo , Microalgas
13.
Aquat Toxicol ; 210: 117-128, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30849631

RESUMO

The widespread presence of herbicides in the aquatic environment has raised awareness about the need to develop further in depth ecotoxicological risk assessments, more specifically on potential effects on photosynthetic organisms as microalgae. The majority of the information available regarding the toxicity of herbicides towards microalgae is related to traditional toxicological and regulatory-relevant endpoints such as growth inhibition, leaving a significant gap on knowledge regarding underlying interactions and damage to biological targets. In this context, this study aimed to supplement the general toxicity information of bifenox and metribuzin in the microalgae Chlamydomonas reinhardtii using a battery of selected high-throughput methods. This multiple-endpoint approach included the measurement of formation of reactive oxygen species (ROS), alterations in reduced glutathione (GSH) content, formation of lipid peroxidation (LPO), photosystem II (PSII) performance and loss of photosynthetic pigments after 24 h exposure. Results obtained showed that both herbicides caused a concentration-dependent increase in ROS formation, with bifenox showing higher but less reactive ROS. This increase in ROS production by bifenox and metribuzin was followed by alterations in the antioxidant capacity of algae, oxidative damage in the form of LPO and alterations in pigment content. Furthermore, both herbicides impacted the photosynthetic activity of algae, as seen by alterations in the maximum and effective quantum efficiency of PSII, PSII photochemistry and energy dissipation pathways, impact in the water-splitting apparatus and reduction in the electron transport rate. The inhibitory effect of metribuzin on photosynthetic processes/components was larger than that seen for bifenox. The impact of bifenox and metribuzin in the photosynthetic processes of C. reinhardtii seems to be in close association with the formation of ROS and consequent oxidative stress and damage in algal cells. Overall, this study showed that the high-throughput methods developed could successfully characterise both potential Modes of Action and adverse effects of bifenox and metribuzin in C. reinhardtii.


Assuntos
Chlamydomonas reinhardtii/efeitos dos fármacos , Herbicidas/toxicidade , Microalgas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Éteres Fenílicos/toxicidade , Triazinas/toxicidade , Poluentes Químicos da Água/toxicidade , Peroxidação de Lipídeos/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Complexo de Proteína do Fotossistema II/metabolismo , Espécies Reativas de Oxigênio/metabolismo
15.
Environ Int ; 114: 95-106, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29499452

RESUMO

Chemicals in the environment occur in mixtures rather than as individual entities. Environmental quality monitoring thus faces the challenge to comprehensively assess a multitude of contaminants and potential adverse effects. Effect-based methods have been suggested as complements to chemical analytical characterisation of complex pollution patterns. The regularly observed discrepancy between chemical and biological assessments of adverse effects due to contaminants in the field may be either due to unidentified contaminants or result from interactions of compounds in mixtures. Here, we present an interlaboratory study where individual compounds and their mixtures were investigated by extensive concentration-effect analysis using 19 different bioassays. The assay panel consisted of 5 whole organism assays measuring apical effects and 14 cell- and organism-based bioassays with more specific effect observations. Twelve organic water pollutants of diverse structure and unique known modes of action were studied individually and as mixtures mirroring exposure scenarios in freshwaters. We compared the observed mixture effects against component-based mixture effect predictions derived from additivity expectations (assumption of non-interaction). Most of the assays detected the mixture response of the active components as predicted even against a background of other inactive contaminants. When none of the mixture components showed any activity by themselves then the mixture also was without effects. The mixture effects observed using apical endpoints fell in the middle of a prediction window defined by the additivity predictions for concentration addition and independent action, reflecting well the diversity of the anticipated modes of action. In one case, an unexpectedly reduced solubility of one of the mixture components led to mixture responses that fell short of the predictions of both additivity mixture models. The majority of the specific cell- and organism-based endpoints produced mixture responses in agreement with the additivity expectation of concentration addition. Exceptionally, expected (additive) mixture response did not occur due to masking effects such as general toxicity from other compounds. Generally, deviations from an additivity expectation could be explained due to experimental factors, specific limitations of the effect endpoint or masking side effects such as cytotoxicity in in vitro assays. The majority of bioassays were able to quantitatively detect the predicted non-interactive, additive combined effect of the specifically bioactive compounds against a background of complex mixture of other chemicals in the sample. This supports the use of a combination of chemical and bioanalytical monitoring tools for the identification of chemicals that drive a specific mixture effect. Furthermore, we demonstrated that a panel of bioassays can provide a diverse profile of effect responses to a complex contaminated sample. This could be extended towards representing mixture adverse outcome pathways. Our findings support the ongoing development of bioanalytical tools for (i) compiling comprehensive effect-based batteries for water quality assessment, (ii) designing tailored surveillance methods to safeguard specific water uses, and (iii) devising strategies for effect-based diagnosis of complex contamination.


Assuntos
Bioensaio , Exposição Ambiental/análise , Modelos Biológicos , Poluentes Químicos da Água , Animais , Células Cultivadas , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
16.
J Toxicol Environ Health A ; 80(16-18): 971-986, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28850005

RESUMO

Biocides are extensively used and universally distributed. Some are highly toxic to algae, including antifoulants, herbicides, and fungicides. The inhibition of algal growth is an important regulatory endpoint for toxicity assessment of single compounds. However, in the aquatic environment, mixtures of compounds with unknown toxicities and mode of action (MoA) co-exist, making single toxicity assessment inadequate to ensure protection of the aquatic environment. This study aimed to characterize the combined toxicity of five environmentally relevant biocides-aclonifen, bifenox, dichlofluanid, metribuzin, and triclosan-with different MoA on growth and photosystem (PS) II efficiency of Chlamydomonas reinhardtii. For growth inhibition, herbicides bifenox and metribuzin were the most toxic, whereas triclosan was least. Only aclonifen and metribuzin exerted a significant effect on PSII, which was also correlated with reduced algal growth. The combined effect of the five biocides on growth inhibition was predominantly additive and presumed to act by independent MoA with potential antagonism observed only at low concentrations and at shorter duration of exposure. The binary mixture of metribuzin and aclonifen exhibited additive effects on diminished PSII efficiency, and effects were apparently induced by an independent MoA. Potential synergy of this mixture on growth inhibition was identified at the highest concentrations. Growth inhibition was found to be a more valuable endpoint for regulatory studies than PSII inhibition due to its environmental relevance, integration of multiple MoA and sensitivity.


Assuntos
Chlamydomonas reinhardtii/efeitos dos fármacos , Desinfetantes/toxicidade , Complexo de Proteína do Fotossistema II/metabolismo , Poluentes Químicos da Água/toxicidade , Compostos de Anilina/toxicidade , Chlamydomonas reinhardtii/crescimento & desenvolvimento , Determinação de Ponto Final , Herbicidas/toxicidade , Éteres Fenílicos/toxicidade , Testes de Toxicidade , Triazinas/toxicidade , Triclosan/toxicidade
17.
Sci Total Environ ; 601-602: 1849-1868, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28629112

RESUMO

Growing concern about the adverse environmental and human health effects of a wide range of micropollutants requires the development of novel tools and approaches to enable holistic monitoring of their occurrence, fate and effects in the aquatic environment. A European-wide demonstration program (EDP) for effect-based monitoring of micropollutants in surface waters was carried out within the Marie Curie Initial Training Network EDA-EMERGE. The main objectives of the EDP were to apply a simplified protocol for effect-directed analysis, to link biological effects to target compounds and to estimate their risk to aquatic biota. Onsite large volume solid phase extraction of 50 L of surface water was performed at 18 sampling sites in four European river basins. Extracts were subjected to effect-based analysis (toxicity to algae, fish embryo toxicity, neurotoxicity, (anti-)estrogenicity, (anti-)androgenicity, glucocorticoid activity and thyroid activity), to target analysis (151 organic micropollutants) and to nontarget screening. The most pronounced effects were estrogenicity, toxicity to algae and fish embryo toxicity. In most bioassays, major portions of the observed effects could not be explained by target compounds, especially in case of androgenicity, glucocorticoid activity and fish embryo toxicity. Estrone and nonylphenoxyacetic acid were identified as the strongest contributors to estrogenicity, while herbicides, with a minor contribution from other micropollutants, were linked to the observed toxicity to algae. Fipronil and nonylphenol were partially responsible for the fish embryo toxicity. Within the EDP, 21 target compounds were prioritized on the basis of their frequency and extent of exceedance of predicted no effect concentrations. The EDP priority list included 6 compounds, which are already addressed by European legislation, and 15 micropollutants that may be important for future monitoring of surface waters. The study presents a novel simplified protocol for effect-based monitoring and draws a comprehensive picture of the surface water status across Europe.

18.
Aquat Toxicol ; 189: 50-59, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28582701

RESUMO

The toxicity of biocides can be associated with the formation of reactive oxygen species (ROS) and subsequent oxidative damage, interfering with the normal function of photosynthetic organisms. This study investigated the formation and effects of ROS in the unicellular green algae Chlamydomonas reinhardtii exposed to three environmentally relevant biocides, aclonifen, dichlofluanid and triclosan. After a first screening to identify which biocides induced ROS, a 24h multi-endpoint analysis was used to verify the possible consequences. A battery of high-throughput methods was applied in algae for measuring ROS formation, reduced glutathione (GSH), lipid peroxidation (LPO), photosystem (PS) II performance and pigments (chlorophylls a, b and carotenoids). Results show that only aclonifen induced ROS after the first 6h exposure, with the other two biocides not showing any ROS formation. Aclonifen, a Protox and carotenoid inhibitor, induced a concentration-dependent ROS formation, LPO and interfered with algae pigments content, while no alterations were detected in GSH content. A significant effect was also seen in the photosynthetic process, especially a reduction in the maximum and effective quantum yields, accompanied by alterations in energy dissipation in PSII reaction centers and the impairment of the electron transport rate. This study demonstrated the successful use of a battery of high-throughput methods for quickly screening biocides capacity to induce the formation of ROS and the subsequent effects in C. reinhardtii, thus revealing their mode of action (MoA) at concentrations before an impact on growth can become effective.


Assuntos
Chlamydomonas reinhardtii/efeitos dos fármacos , Desinfetantes/toxicidade , Monitoramento Ambiental/métodos , Estresse Oxidativo/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Carotenoides/metabolismo , Chlamydomonas reinhardtii/crescimento & desenvolvimento , Chlamydomonas reinhardtii/metabolismo , Clorofila/metabolismo , Desinfetantes/química , Relação Dose-Resposta a Droga , Transporte de Elétrons/efeitos dos fármacos , Glutationa/metabolismo , Ensaios de Triagem em Larga Escala , Peroxidação de Lipídeos/efeitos dos fármacos , Oxirredução , Complexo de Proteína do Fotossistema II/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Poluentes Químicos da Água/química
19.
BMJ Case Rep ; 20162016 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-27646316

RESUMO

A 64-year-old man presented with a 3-month history of recurrent conjunctivitis. He was evaluated by an ophthalmologist and submitted to a CT scan that revealed an intraconic mass with invasion of the lateral orbital wall. He was operated, the mass was completely removed (with preservation of the intraorbital structures) and the lateral orbital wall rebuilt. The histopathological analysis revealed an adenoid cystic carcinoma of the lacrimal gland. 4 months later a painful recurrence of the lesion was diagnosed with invasion of the orbital roof and eyelids. After a multidisciplinary discussion and request from the patient, an exenteration of the orbit and removal of the lateral and superior orbital wall and dura mater was performed with the objective of a total resection. The wound and orbit were closed with a vertical rectus abdominis myocutaneous free flap to ensure closure.


Assuntos
Carcinoma Adenoide Cístico/cirurgia , Neoplasias Oculares/cirurgia , Retalhos de Tecido Biológico , Aparelho Lacrimal , Recidiva Local de Neoplasia/cirurgia , Exenteração Orbitária , Técnicas de Fechamento de Ferimentos , Carcinoma Adenoide Cístico/patologia , Neoplasias Oculares/patologia , Humanos , Aparelho Lacrimal/patologia , Aparelho Lacrimal/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Órbita/cirurgia , Reto do Abdome/transplante
20.
Viseu; s.n; 20160000. 191 p. ilust, tabelas.
Tese em Português | BDENF - Enfermagem | ID: biblio-1253918

RESUMO

Introdução: Com o aumento da esperança média de vida e do aparecimento de doenças crónicas, a família/amigos têm um papel importante na continuidade de cuidados, podendo acarretar problemas físicos, psicológicos, emocionais, sociais e financeiros, que podem afetar o bem-estar do utente e do próprio cuidador. Assim, o objetivo central consiste em conhecer o nível de sobrecarga e dificuldades sentido pelo cuidador informal da pessoa dependente, e os seus determinantes. Métodos: Este estudo é de natureza quantitativa, descritivo-correlacional e transversal, com recurso a uma amostra não probabilística, acidental e por conveniência, composta por 71 cuidadores informais, com idades entre os 30 - 80 anos (x= 53,73; Dp= 12,001), maioritariamente do sexo feminino (64,79%), casadas (83,2%), residentes em aldeias (50,7%) e com uma média de idades de 53,73 anos (Dp= 12,001). O instrumento de colheita de dados incorporou: Ficha Sociodemográfica; Índice de Barthel; Escala de Apgar Familiar de Smilkstein; Escala de Apoio Social; Questionário de Avaliação da Sobrecarga do Cuidador Informal e Índice de Avaliação das Dificuldades do Cuidador. Resultados: Verificou-se, que as caraterísticas sociodemográficas não influenciam a sobrecarga e dificuldades sentidas pelos cuidadores. No entanto, quanto ao "grau de dependência nas ABVD's" e à "perceção do seu estado de saúde", o grupo de cuidadores de pessoas com dependência severa ou total e aqueles com menor perceção do seu estado de saúde, manifestam maiores índices de sobrecarga e dificuldades. Contrariamente, estão os cuidadores que recebem "apoio financeiro" e "apoio de terceiros quando necessitam de se ausentar", que percecionam menor sobrecarga e dificuldades. Respeitante à "funcionalidade familiar" e "apoio social", os cuidadores informais integrados em famílias com disfunção acentuada e baixo apoio social, manifestam maiores índices de sobrecarga e de dificuldades. Quanto maior são as dificuldades, maior é a sobrecarga sentida pelos cuidadores. Conclusão: Os resultados revelaram, a existência de fatores determinantes da sobrecarga do cuidador, daí a importância duma abordagem multidisciplinar assente em programas de apoio, acompanhamento e orientação diferenciada destes cuidadores, realçando a necessidade de aumentar o índice de bem-estar destas pessoas, para poderem proporcionar, com segurança, cuidados essenciais à pessoa que cuidam, ao mesmo tempo que possam prevenir quadros de sobrecarga física e psicológica nefastos para a sua saúde. Certamente, a enfermagem de reabilitação terá aqui um importante papel a fomentar e a desenvolver.


Introduction: With the increase of life expectancy and chronic disease's emergence, family and friends have a role of extreme importance in the continuity of care. This can lead to physical, psychological, emotional, financial and social problems that can affect the carergiver's well-being. Thus, the main objective is to identify the level of overburden and difficulties experienced by carers and the variables that influence them. Methods: This study is characterized as being quantitative, descriptive, correlational and transversal, using a non-probabilistic, accidental and convenience sample and comprising 71 informal caregivers, aged between 30 and 80 years (x= 53,73; Dp= 12,001), mostly female (64,79%), married (83,2%), village's residents (83,2%) and with an average age of 53,73% (Dp= 12,001). The data collection instruments included: Barthel Index; Smilkstein's Family Apgar Scale; Scale of Social Support; Questionnaire of the Evaluation on the Informal Carer's overburden and Evaluation Index of Carer's Difficulties. Results: The results showed that sociodemographic characteristics do not influence the overburden and difficulties felt by caregivers. However, as for the "degree of dependence in BADL's" and the "perception of their health state", the group of caregivers of people with severe or total dependence and those with less understanding of their health state, demonstrates the highest rates of difficulties and overburden. The same situation happens - regarding the "family functionality" and "social support"- when you have informal caregivers in families with severe dysfunction and low social support. On the other hand, there are the caregivers who receive "financial support" and "thirdparty support when they need to leave", which perceives lower overburden and difficulties. The higher difficulties are, the greater the overload experienced by caregivers. Conclusion: the results revealed the existence of crucial factors on caregiver's overburden, hence the importance of a multidisciplinary approach based on supportive programmes - monitoring and giving personalised guidance to these caregivers - highlighting the need to increase the well-being of these people, so they can safely provide, essential care to the person they're caring for, preventing at the same time physical and psychological overburden. Certainly, the rehabilitation nursing will have here an important role to promote and develop.


Assuntos
Envelhecimento , Família , Efeitos Psicossociais da Doença , Pessoal de Saúde
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