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1.
Retina ; 44(4): 700-706, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38109709

RESUMEN

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.


Asunto(s)
Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Humanos , Estudios Transversales , Vasos Retinianos/patología , Angiografía con Fluoresceína/métodos , Retina/patología , Tomografía de Coherencia Óptica/métodos
2.
Ecotoxicol Environ Saf ; 275: 116244, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38537480

RESUMEN

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.


Asunto(s)
Compuestos Heterocíclicos con 3 Anillos , Lactonas , Contaminantes Químicos del Agua , Pez Cebra , Animales , Larva , Crustáceos , Pruebas de Mutagenicidad , Contaminantes Químicos del Agua/toxicidad
3.
Ophthalmic Res ; 66(1): 1327-1334, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37820590

RESUMEN

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.


Asunto(s)
Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Humanos , Retinopatía Diabética/patología , Diabetes Mellitus Tipo 2/complicaciones , Vasos Retinianos/patología , Estudios Transversales , Angiografía con Fluoresceína/métodos , Retina , Isquemia/diagnóstico , Tomografía de Coherencia Óptica/métodos
4.
Ecotoxicol Environ Saf ; 222: 112553, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34325198

RESUMEN

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.


Asunto(s)
Chlorophyceae , Microalgas , Contaminantes Químicos del Agua , Azitromicina/toxicidad , Agua Dulce , Contaminantes Químicos del Agua/toxicidad
5.
J Toxicol Environ Health A ; 80(16-18): 971-986, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28850005

RESUMEN

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.


Asunto(s)
Chlamydomonas reinhardtii/efectos de los fármacos , Desinfectantes/toxicidad , Complejo de Proteína del Fotosistema II/metabolismo , Contaminantes Químicos del Agua/toxicidad , Compuestos de Anilina/toxicidad , Chlamydomonas reinhardtii/crecimiento & desarrollo , Determinación de Punto Final , Herbicidas/toxicidad , Éteres Fenílicos/toxicidad , Pruebas de Toxicidad , Triazinas/toxicidad , Triclosán/toxicidad
6.
J Hazard Mater ; 458: 131810, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37336109

RESUMEN

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.


Asunto(s)
Plásticos , Goma , Humanos , Compuestos Orgánicos , Polímeros , Elastómeros , Bacterias
7.
Br J Ophthalmol ; 107(8): 1132-1138, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-35277395

RESUMEN

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.


Asunto(s)
Retinopatía de la Prematuridad , Recién Nacido , Lactante , Humanos , Retinopatía de la Prematuridad/diagnóstico , Retinopatía de la Prematuridad/epidemiología , Retinopatía de la Prematuridad/terapia , Suecia/epidemiología , Factores de Riesgo , Recien Nacido Prematuro , Peso al Nacer , Edad Gestacional , Tamizaje Neonatal , Estudios Retrospectivos
8.
Front Cell Infect Microbiol ; 11: 678568, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34327150

RESUMEN

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.


Asunto(s)
Trampas Extracelulares , Candida , Candida albicans , Humanos , Neutrófilos , Nucleótidos
9.
Sci Total Environ ; 726: 138547, 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32320882

RESUMEN

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.


Asunto(s)
Microalgas , Contaminantes Químicos del Agua , Ecosistema , Polimetil Metacrilato , Poliestirenos
10.
Int J Biol Macromol ; 157: 119-134, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32335118

RESUMEN

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.


Asunto(s)
Catecoles/química , Quitosano/química , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Vidrio/química , Ácido Hialurónico/química , Nanopartículas/química , Adhesividad , Regeneración Tisular Dirigida , Viscosidad
11.
Aquat Toxicol ; 210: 117-128, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30849631

RESUMEN

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.


Asunto(s)
Chlamydomonas reinhardtii/efectos de los fármacos , Herbicidas/toxicidad , Microalgas/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Éteres Fenílicos/toxicidad , Triazinas/toxicidad , Contaminantes Químicos del Agua/toxicidad , Peroxidación de Lípido/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Complejo de Proteína del Fotosistema II/metabolismo , Especies Reactivas de Oxígeno/metabolismo
12.
Sci Total Environ ; 687: 827-838, 2019 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-31412486

RESUMEN

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.


Asunto(s)
Chlorophyceae/efectos de los fármacos , Pruebas de Toxicidad/métodos , Contaminantes Químicos del Agua/toxicidad , Biomarcadores , Monitoreo del Ambiente/métodos , Citometría de Flujo , Microalgas
13.
Environ Int ; 114: 95-106, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29499452

RESUMEN

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.


Asunto(s)
Bioensayo , Exposición a Riesgos Ambientales/análisis , Modelos Biológicos , Contaminantes Químicos del Agua , Animales , Células Cultivadas , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
14.
Aquat Toxicol ; 189: 50-59, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28582701

RESUMEN

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.


Asunto(s)
Chlamydomonas reinhardtii/efectos de los fármacos , Desinfectantes/toxicidad , Monitoreo del Ambiente/métodos , Estrés Oxidativo/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Carotenoides/metabolismo , Chlamydomonas reinhardtii/crecimiento & desarrollo , Chlamydomonas reinhardtii/metabolismo , Clorofila/metabolismo , Desinfectantes/química , Relación Dosis-Respuesta a Droga , Transporte de Electrón/efectos de los fármacos , Glutatión/metabolismo , Ensayos Analíticos de Alto Rendimiento , Peroxidación de Lípido/efectos de los fármacos , Oxidación-Reducción , Complejo de Proteína del Fotosistema II/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Contaminantes Químicos del Agua/química
15.
Sci Total Environ ; 601-602: 1849-1868, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28629112

RESUMEN

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.

16.
BMJ Case Rep ; 20162016 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-27646316

RESUMEN

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.


Asunto(s)
Carcinoma Adenoide Quístico/cirugía , Neoplasias del Ojo/cirugía , Colgajos Tisulares Libres , Aparato Lagrimal , Recurrencia Local de Neoplasia/cirugía , Evisceración Orbitaria , Técnicas de Cierre de Heridas , Carcinoma Adenoide Quístico/patología , Neoplasias del Ojo/patología , Humanos , Aparato Lagrimal/patología , Aparato Lagrimal/cirugía , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Órbita/cirugía , Recto del Abdomen/trasplante
17.
Rev. bras. oftalmol ; 80(3): e0002, 2021. graf
Artículo en Inglés | LILACS | ID: biblio-1251329

RESUMEN

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.


Asunto(s)
Humanos , Masculino , Anciano de 80 o más Años , Adhesivo de Tejido de Fibrina/uso terapéutico , Enfermedades de la Conjuntiva/cirugía , Litiasis/cirugía , Amnios/trasplante
18.
BMJ Case Rep ; 20142014 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-24920512

RESUMEN

Cryptococcal meningitis is associated with significant morbidity and is rare among immunocompetent patients. Clinical presentation as well as the course of disease is usually indolent which may delay the diagnosis. We present the case of a 52-year-old woman admitted with headaches, vomiting and fatigue for 3 weeks. She was diagnosed with cryptococcal meningitis and treated with antifungal therapy. She was referred for ophthalmological examination presenting with decreased vision in the left eye (OS; count fingers), left relative afferent pupillary defect and bilateral sixth nerve palsy. Funduscopy revealed florid bilateral papilloedema. Cranial MRI showed indirect signs of intracranial hypertension as well as multiple parenchymal lesions and optic nerve sheath enhancement after contrast administration. A ventriculoperitoneal shunt was placed. In spite of the control of intracranial pressure there was a decrease in vision in the right eye (OD) and deterioration of visual fields. Intravenous methylprednisolone was used to reverse optic neuropathy and to prevent OD visual loss.


Asunto(s)
Cryptococcus neoformans , Inmunocompetencia/fisiología , Meningitis Criptocócica/complicaciones , Enfermedades del Nervio Óptico/microbiología , Ceguera/prevención & control , Femenino , Humanos , Hipertensión Intracraneal/microbiología , Metilprednisolona/uso terapéutico , Persona de Mediana Edad , Fármacos Neuroprotectores/uso terapéutico , Enfermedades del Nervio Óptico/tratamiento farmacológico
19.
Eur J Ophthalmol ; 23(6): 789-92, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23640507

RESUMEN

PURPOSE: To study the correlation among cataract grading system by Scheimpflug imaging (Oculus Pentacam® Nucleus Grading System [PNS]), effective phaco time (EPT), and surgical time (ST) using peristaltic and venturi pumps on the Whitestar Signature Phaco System (Abbott Medical Optics, Inc., Santa Ana, California, USA). 
 METHODS: Patients scheduled to have bimanual microincision phacoemulsification by the same surgeon (T.F.) had Pentacam® Scheimpflug assessment using PNS and were randomly distributed into 2 groups. In group 1, surgery was performed using peristaltic pump, and in group 2, using venturi pump. Parameters assessed in both groups included EPT and ST. 
 RESULTS: Sixty eyes that had uneventful clear cornea phacoemulsification with implantation of foldable intraocular lens (IOL) were evaluated, 30 in each group. The EPT was statistically superior with higher nuclear density grades for both groups 1 and 2 (group 1 Spearman R = 0.739, p<0.001; group 2 Spearman R = 0.924, p<0.001). The ST statistically increased with nucleus density for both groups 1 and 2 (group 1 Spearman R = 0.620, p<0.001; group 2 Spearman R = 0.643, p<0.001). Group 2 presented statistically significant reduction on median ST compared with group 1 for nucleus grading 2, 3, 4, and 5. CONCLUSIONS: The PNS is an objective and reproducible method of grading nuclear cataract density and had a correlation with EPT. Peristaltic and venturi pumps in Signature Phaco System were similar in EPT but venturi pump reduced the median ST in nucleus with higher PNS, without repercussion on complications or anterior chamber stability.


Asunto(s)
Catarata/clasificación , Diagnóstico por Imagen/métodos , Implantación de Lentes Intraoculares , Núcleo del Cristalino/patología , Facoemulsificación/instrumentación , Anciano , Anciano de 80 o más Años , Cámara Anterior , Femenino , Humanos , Masculino , Tempo Operativo , Facoemulsificación/métodos , Estudios Prospectivos , Distribución Aleatoria , Factores de Tiempo
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