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1.
Eur J Clin Microbiol Infect Dis ; 43(4): 703-712, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38326546

RESUMO

PURPOSE: Elderly patients admitted to geriatrics departments often require peripheral venous catheters (PVC), which should be inserted and maintained following a series of preventive recommendations. Our objective was to evaluate the impact of a training bundle comprising measures aimed at reducing complications associated with the use of PVC in elderly patients admitted to a tertiary teaching hospital. METHODS: We performed a prospective study of patients who received a PVC within 24 h of admission to a geriatrics department. After a 10-month pre-interventional period, we implemented an educational and interventional bundle over a 9-month period. Follow-up was until catheter withdrawal. We analyzed and compared clinical and microbiological data between both study periods. RESULTS: A total of 344 patients (475 PVC) were included (pre-intervention period, 204 patients (285 PVC); post-intervention period, 140 patients (190 PVC)). No statistically significant differences in demographic characteristics were observed between the study periods. The colonization and phlebitis rates per 1000 admissions in both periods were, respectively, 36.7 vs. 24.3 (p = 0.198) and 81.5 vs. 65.1 (p = 0.457). The main reason for catheter withdrawal was obstruction/malfunctioning (33.3%). Obstruction rate was higher for those inserted in the hand than for those inserted at other sites (55.7% vs. 44.3%, p = 0.045). CONCLUSIONS: We found no statistically significant differences regarding phlebitis and catheter tip colonization rates. It is necessary to carry out randomized studies assessing the most cost-effective measure to reduce complications associated with PVC.


Assuntos
Cateterismo Periférico , Flebite , Humanos , Idoso , Estudos Prospectivos , Cateterismo Periférico/efeitos adversos , Catéteres/efeitos adversos , Flebite/etiologia , Flebite/prevenção & controle , Pacientes
2.
Environ Res ; 245: 118072, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38157971

RESUMO

Fish acute toxicity tests are commonly used in aquatic environmental risk assessments, being required in different international substances regulations. A general trend in the toxicity testing of nanomaterials (NMs) has been to use standardized aquatic toxicity tests. However, as these tests were primarily developed for soluble chemical, issues regarding particle dissolution, agglomeration or sedimentation during the time of exposure are not considered when reporting the toxicity of NMs. The aim of this study was to characterize the NM behaviour throughout the fish acute test and to provide criteria to assay the toxicity of nine NMs based on TiO2, ZnO, SiO2, BaSO4, bentonite, and carbon nanotubes, on rainbow trout following OECD Test Guideline (TG) nº203. Our results showed the importance of conducting a preliminary test (without fish) when working with NMs. They provide valuable information on, sample monitoring, agglomeration, sedimentation, dissolution, actual concentrations of NMs, needed to design the test. Among the NMs tested, only bentonite nanoparticles were stable during the 96-h pre-test and test in aquarium water. In contrast, the remaining NMs exhibited considerable loss and sedimentation within the first 24 h. The high sedimentation observed for almost all NMs highlights the need of consistently measuring the concentrations throughout the entire duration of the fish acute toxicity test to make reliable concentration-response relationships. Notable differences emerged in LC50 values when using actual concentrations as nominal concentrations overestimated concentrations by up to 85.6%. Among all NMs tested, only ZnO NMs were toxic to rainbow trout. A flow chart was specifically developed for OECD TG 203, aiding users in making informed decisions regarding the selection of test systems and necessary modifications to ensure accurate, reliable, and reusable toxicity data. Our findings might contribute to the harmonization of TG 203 improving result reproducibility and interpretability and supporting the development of read-across and QSAR models.


Assuntos
Nanoestruturas , Nanotubos de Carbono , Óxido de Zinco , Animais , Dióxido de Silício , Nanotubos de Carbono/toxicidade , Reprodutibilidade dos Testes , Bentonita , Nanoestruturas/química , Peixes
3.
Regul Toxicol Pharmacol ; 139: 105360, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36804527

RESUMO

Over the recent years, EU chemicals legislation, guidance and test guidelines have been developed or adapted for nanomaterials to facilitate safe use of nanomaterials. This paper provides an overview of the information requirements across different EU regulatory areas. For each information requirement, a group of 22 experts identified potential needs for further action to accommodate guidance and test guidelines to nanomaterials. Eleven different needs for action were identified, capturing twenty-two information requirements that are specific to nanomaterials and relevant to multiple regulatory areas. These were further reduced to three overarching issues: 1) resolve issues around nanomaterial dispersion stability and dosing in toxicity testing, in particular for human health endpoints, 2) further develop tests or guidance on degradation and transformation of organic nanomaterials or nanomaterials with organic components, and 3) further develop tests and guidance to measure (a)cellular reactivity of nanomaterials. Efforts towards addressing these issues will result in better fit-for-purpose test methods for (EU) regulatory compliance. Moreover, it secures validity of hazard and risk assessments of nanomaterials. The results of the study accentuate the need for a structural process of identification of information needs and knowledge generation, preferably as part of risk governance and closely connected to technological innovation policy.


Assuntos
Segurança Química , Nanoestruturas , Humanos , Nanoestruturas/toxicidade , Políticas , Medição de Risco/métodos , Testes de Toxicidade/métodos
4.
Appl Opt ; 61(19): 5657-5665, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36255795

RESUMO

An alternative method is proposed to generate a modified random phase that is able to concentrate the light around a given direction, produces well-contrasted Fourier amplitude holograms, reduces the quantity and the randomness of the speckle noise in the image, and decreases the amount of data necessary for the phase definition. This modified limited bandwidth random phase uses structured random phase patterns to control the object dispersion. The resulting hologram displays an image with structured speckle noise (SSN), exhibiting similar metrics as the iterative method for hologram generation. A filtering process eliminates the SSN; the speckle contrast in the final image is reduced from 0.66 to 0.07; and the peak SNR increases from 7.21 dB to 12.62 dB. This method enhances the fine details and grayscale tone perception in the final image.

5.
Ecotoxicol Environ Saf ; 227: 112949, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34755633

RESUMO

The current environmental hazard assessment is based on the testing of the pristine substance. However, it cannot be excluded that (nano)pharmaceuticals are excreted into sewage during the use phase followed by entry into wastewater treatment plants (WWTPs). Sorption to sewage sludge or release via effluent can result in modified ecotoxicological effects which possibly can only be detected with a modified test approach. The objective of our study was to investigate a realistic exposure scenario for metallic nanoparticles (NPs) in pharmaceutical products, excreted into effluent, and released into the environment after treatment in WWTPs. The test approach was illustrated by using gold (Au) NPs. Effluent from model WWTPs were investigated in aquatic tests (Daphnia magna, fish cell lines). Sewage sludge was used as a sole food source (Eisenia fetida) or mixed with soil and used as test medium (soil microorganisms, Folsomia candida, Enchytraeus crypticus). To cover the aspect of regulation, the test systems described in OECD-test guidelines (OECD TG 201, 211, 220, 232, 249, 317) were applied. Modifications and additional test approaches were included to meet the needs arising out of the testing of nanomaterials and of the exposure scenarios. The results were assessed regarding the suitability of the test design and the toxicity of Au-NPs. Except for activated sludge as a sole food source for E.fetida, the selected test approach is suitable for the testing of nanomaterials. Additional information can be gained when compared to the common testing of the pristine nanomaterials in the standardized test systems. Effects of Au-NPs were observed in concentrations exceeding the modeled environmental.


Assuntos
Nanopartículas Metálicas , Oligoquetos , Preparações Farmacêuticas/análise , Animais , Linhagem Celular , Daphnia , Ecotoxicologia , Peixes , Nanopartículas Metálicas/análise , Nanopartículas Metálicas/toxicidade , Esgotos , Testes de Toxicidade
6.
Artigo em Inglês | MEDLINE | ID: mdl-33112704

RESUMO

This study was focused to determine an individual and combined effect of mycotoxin citrinin (CIT) and two compounds of the stilbene family- resveratrol (RES) and his dimethyl ether analogue pterostilbene (PTE) which have many health benefits. As a model the human adenocarcinoma cell line HT-29 was used which may exhibits the properties of small intestine cells. Viability, plasma membrane integrity, lysosomal functionality, intracellular production of superoxide anions and superoxide dismutase activity were examined. The results indicate that concentrations of 50 and 100 µg/mL of the tested compounds were cytotoxic in mostly monitored parameters and probably caused apoptosis. HT-29 cells were more sensitive to PTE than to RES with a higher antioxidant effect of PTE than RES, which may be caused by its chemical structure. Both stilbenes at medium doses act as effective superoxide anions scavengers leading to reduction of oxidative stress and consequent cell damage. The nontoxic concentration of RES (25 µg/mL) protects the HT-29 cell line faced to the toxicity of CIT at 25 µg/mL by increasing viability of cells and by reducing the superoxide production induced by CIT concentrations of 12.5 µg/mL and 25 µg/mL.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Citrinina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Resveratrol/farmacologia , Estilbenos/farmacologia , Antioxidantes/administração & dosagem , Membrana Celular/efeitos dos fármacos , Membrana Celular/patologia , Sobrevivência Celular/efeitos dos fármacos , Citrinina/administração & dosagem , Relação Dose-Resposta a Droga , Interações Medicamentosas , Células HT29 , Humanos , Resveratrol/administração & dosagem , Estilbenos/administração & dosagem
7.
Ecotoxicol Environ Saf ; 205: 111291, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956865

RESUMO

The purpose of this study was to determine the acute toxicity in aquatic organisms of one biocidal active substance and six metabolites derived from biocidal active substances and to assess the suitability of available QSAR models to predict the obtained values. We have reported the acute toxicity in sewage treatment plant (STP) microorganisms, in the freshwater microalgae Pseudokirchneriella subcapitata and in Daphnia magna following OECD test methods. We have also identified in silico models for acute toxicity of these trophic levels currently available in widely recognized platforms such as VEGA and the OECD QSAR ToolBox. A total of six, four and two models have been selected for Daphnia, algae and microorganisms, respectively. Finally, we have compared the in silico and in vivo data for the seven compounds plus two previously assayed biocidal substances. None of the compounds tested were toxic for Daphnia and STP microorganisms. For microalgae, CGA71019 (1,2,4 triazole) presented an ErC50 value of 38.3 mg/L. The selected in silico models have provided lower EC50 values and are therefore more conservative. Models from the OECD QSAR ToolBox predicted values for 7 out of 9 and for 4 out of 9 chemicals for Daphnia and P. subcapitata, respectively. No predictive models were identified in such platform for STP microorganism's acute effects. In terms of models's specificity, biocide-specific models, developed from curated datasets integrated by biocidal active substances and implemented in VEGA, perform better in the case of microalgae but for Daphnia an alternative, non biocide-specific has revealed a better performance. For STP microorganisms only biocide-specific models have been identified.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Desinfetantes/toxicidade , Modelos Biológicos , Poluentes Químicos da Água/toxicidade , Animais , Clorofíceas/efeitos dos fármacos , Simulação por Computador , Daphnia/efeitos dos fármacos , Desinfetantes/química , Desinfetantes/metabolismo , Água Doce/química , Microalgas/efeitos dos fármacos , Relação Quantitativa Estrutura-Atividade , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo
8.
Appl Opt ; 58(8): 1917-1923, 2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30874056

RESUMO

In computer generated holograms, a random phase is added to spread out the object wave, but this introduces a strong speckle noise in the reconstructed image. Spreading out the object wave helps to record a large object in a smaller hologram. We propose a random repeated and displaced phase, which reduces the speckle noise in the reconstructed image and spreads out the object information in a limited area. The phase is independent of the object, and it could be calculated by sections reducing the hologram computing time. We present simulated and experimental results that prove the improvement in quality of the reconstructed image and the whole object reconstruction, using only a small part of the hologram.

9.
Ecotoxicol Environ Saf ; 138: 309-319, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28062079

RESUMO

Titanium dioxide nanoparticles (TiO2-NPs) have a wide number of applications in cosmetic, solar and paint industries due to their photocatalyst and ultraviolet blocking properties. The continuous increase in the production of TiO2-NPs enhances the risk for this manufactured nanomaterial to enter water bodies through treated effluents or agricultural amendments. TiO2-NPs have shown very low toxicity in a number of aquatic organisms. However, there are no conclusive data about their deleterious effects and on their possible mechanisms of toxic action. At this level, in vitro cell culture systems are a useful tool to gain insight about processes underlying the toxicity of a wide variety of substances, including nanomaterials. Differences in the physiology of different taxa make advisable the use of cells coming from the taxon of interest, but collecting data from a variety of cellular types allows a better understanding of the studied processes. Taking all this into account, the aim of the present study was to assess the toxicity of three types of TiO2-NP, rutile hydrophobic (NM-103), rutile hydrophilic (NM-104) and rutile-anatase (NM-105), obtained from the EU Joint Research Centre (JRC) repository, using various fish cell lines (RTG-2, PLHC-1, RTH-149, RTL-W1) and rainbow trout primary hepatocytes. For comparative purposes, the effect of different dispersion protocols, end-point assays and extended exposure time was studied in a fish cell line (RTG-2) and in the rat hepatoma cell line (H4IIE). TiO2-NPs dispersions showed a variable degree of aggregation in cell culture media. Disruption of mitochondrial metabolic activity, plasma membrane integrity and lysosome function was not detected in any cell line after exposure to TiO2-NPs at any time and concentration ranges tested. These results are indicative of a low toxicity of the TiO2-NPs tested and show the usefulness of fish cells maintained in vitro as high throughput screening methods that can facilitate further testing in the framework of integrated testing strategies.


Assuntos
Membrana Celular/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Mitocôndrias/efeitos dos fármacos , Titânio/toxicidade , Animais , Carcinoma Hepatocelular , Linhagem Celular Tumoral , Hepatócitos , Interações Hidrofóbicas e Hidrofílicas , Oncorhynchus mykiss , Ratos
10.
BMC Vet Res ; 10: 14, 2014 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-24410926

RESUMO

BACKGROUND: Despite great effort and investment incurred over decades to control bovine tuberculosis (bTB), it is still one of the most important zoonotic diseases in many areas of the world. Test-and-slaughter strategies, the basis of most bTB eradication programs carried out worldwide, have demonstrated its usefulness in the control of the disease. However, in certain countries, eradication has not been achieved due in part to limitations of currently available diagnostic tests. In this study, results of in-vivo and post-mortem diagnostic tests performed on 3,614 animals from 152 bTB-infected cattle herds (beef, dairy, and bullfighting) detected in 2007-2010 in the region of Castilla y León, Spain, were analyzed to identify factors associated with positive bacteriological results in cattle that were non-reactors to the single intradermal tuberculin test, to the interferon-gamma (IFN-γ) assay, or to both tests applied in parallel (Test negative/Culture + animals, T-/C+). The association of individual factors (age, productive type, and number of herd-tests performed since the disclosure of the outbreak) with the bacteriology outcome (positive/negative) was analyzed using a mixed multivariate logistic regression model. RESULTS: The proportion of non-reactors with a positive post-mortem result ranged from 24.3% in the case of the SIT test to 12.9% (IFN-γ with 0.05 threshold) and 11.9% (95% CI 9.9-11.4%) using both tests in parallel. Older (>4.5 years) and bullfighting cattle were associated with increased odds of confirmed bTB infection by bacteriology, whereas dairy cattle showed a significantly lower risk. Ancillary use of IFN-γ assay reduced the proportion of T-/C + animals in high risk groups. CONCLUSIONS: These results demonstrate the likelihood of positive bacteriological results in non-reactor cattle is influenced by individual epidemiological factors of tested animals. Increased surveillance on non-reactors with an increased probability of being false negative could be helpful to avoid bTB persistence, particularly in chronically infected herds. These findings may aid in the development of effective strategies for eradication of bTB in Spain.


Assuntos
Teste Tuberculínico/veterinária , Tuberculose Bovina/diagnóstico , Animais , Bovinos , Reações Falso-Negativas , Interferon gama , Modelos Logísticos , Análise Multivariada , Fatores de Risco , Sensibilidade e Especificidade , Espanha/epidemiologia , Teste Tuberculínico/normas , Tuberculose Bovina/epidemiologia
11.
Toxics ; 12(2)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38393237

RESUMO

The peculiar physico-chemical characteristics of nanomaterials (NMs) and the use of different coatings to improve their expected properties result in a huge amount of nanoforms, which vary in chemical composition, size, shape and surface characteristics. This makes it almost impossible to test all the nanoforms available, and efforts have been made to establish grouping or read-across strategies. The aim of this work was to find a behavior pattern of effect among nanoforms of different metallic core nanoparticles (NPs) (TiO2, CeO2 and Ag NP) with the same coatings (sodium citrate, poly (ethylene glycol), dodecylphosphonic acid or oleylamine). Daphnia magna, rainbow trout and two fish cell lines (PLHC-1 and RTH-149) were exposed to a range of concentrations (up to 100 mg/L) of the uncoated or coated NPs. Ag NPs were the most toxic, followed by CeO2 NPs and finally by TiO2 NPs. The results show that a clear pattern of toxicity in the studied species could not be established related to the coatings. However, it was possible to confirm different inter-species sensitivities. RTH-149 was the most sensitive cell line, and Daphnia magna was more sensitive than fish. Moreover, some differences in coating-core interactions were found between the metal oxide and the metal NPs in Daphnia magna.

12.
Nat Protoc ; 19(9): 2642-2684, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38755447

RESUMO

Making research data findable, accessible, interoperable and reusable (FAIR) is typically hampered by a lack of skills in technical aspects of data management by data generators and a lack of resources. We developed a Template Wizard for researchers to easily create templates suitable for consistently capturing data and metadata from their experiments. The templates are easy to use and enable the compilation of machine-readable metadata to accompany data generation and align them to existing community standards and databases, such as eNanoMapper, streamlining the adoption of the FAIR principles. These templates are citable objects and are available as online tools. The Template Wizard is designed to be user friendly and facilitates using and reusing existing templates for new projects or project extensions. The wizard is accompanied by an online template validator, which allows self-evaluation of the template (to ensure mapping to the data schema and machine readability of the captured data) and transformation by an open-source parser into machine-readable formats, compliant with the FAIR principles. The templates are based on extensive collective experience in nanosafety data collection and include over 60 harmonized data entry templates for physicochemical characterization and hazard assessment (cell viability, genotoxicity, environmental organism dose-response tests, omics), as well as exposure and release studies. The templates are generalizable across fields and have already been extended and adapted for microplastics and advanced materials research. The harmonized templates improve the reliability of interlaboratory comparisons, data reuse and meta-analyses and can facilitate the safety evaluation and regulation process for (nano) materials.


Assuntos
Nanoestruturas , Nanoestruturas/química , Software , Metadados
13.
Part Fibre Toxicol ; 10: 27, 2013 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-23849434

RESUMO

BACKGROUND: Graphene and graphene derivative nanoplatelets represent a new generation of nanomaterials with unique physico-chemical properties and high potential for use in composite materials and biomedical devices. To date little is known about the impact graphene nanomaterials may have on human health in the case of accidental or intentional exposure. The objective of this study was to assess the cytotoxic potential of graphene nanoplatelets with different surface chemistry towards a human hepatoma cell line, Hep G2, and identify the underlying toxicity targets. METHODS: Graphene oxide (GO) and carboxyl graphene (CXYG) nanoplatelet suspensions were obtained in water and culture medium. Size frequency distribution of the suspensions was determined by means of dynamic light scattering. Height, lateral dimension and shape of the nanoplatelets were determined using atomic force and electron microscopy. Cytotoxicity of GO and CXYG nanoplatelets was assessed in Hep G2 cells using a battery of assays covering different modes of action including alterations of metabolic activity, plasma membrane integrity and lysosomal function. Induction of oxidative stress was assessed by measuring intracellular reactive oxygen species levels. Interaction with the plasma membrane, internalization and intracellular fate of GO and CXYG nanoplatelets was studied by scanning and transmission electron microscopy. RESULTS: Supplementing culture medium with serum was essential to obtain stable GO and CXYG suspensions. Both graphene derivatives had high affinity for the plasma membrane and caused structural damage of the latter at concentrations as low as 4 µg/ml. The nanoplatelets penetrated through the membrane into the cytosol, where they were concentrated and enclosed in vesicles. GO and CXYG accumulation in the cytosol was accompanied by an increase in intracellular reactive oxygen species (ROS) levels, alterations in cellular ultrastructure and changes in metabolic activity. CONCLUSIONS: GO and CXYG nanoplatelets caused dose- and time-dependent cytotoxicity in Hep G2 cells with plasma membrane damage and induction of oxidative stress being important modes of toxicity. Both graphene derivatives were internalized by Hep G2, a non-phagocytotic cell line. Moreover, they exerted no toxicity when applied at very low concentrations (< 4 µg/ml). GO and CXYG nanoplatelets may therefore represent an attractive material for biomedical applications.


Assuntos
Carcinoma Hepatocelular/patologia , Membrana Celular/efeitos dos fármacos , Grafite/toxicidade , Neoplasias Hepáticas/patologia , Nanoestruturas/toxicidade , Transporte Biológico , Carcinoma Hepatocelular/metabolismo , Membrana Celular/metabolismo , Membrana Celular/patologia , Citosol/metabolismo , Relação Dose-Resposta a Droga , Metabolismo Energético/efeitos dos fármacos , Grafite/química , Grafite/metabolismo , Células Hep G2 , Humanos , Luz , Neoplasias Hepáticas/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Nanoestruturas/química , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Medição de Risco , Espalhamento de Radiação , Propriedades de Superfície , Fatores de Tempo
14.
Nanomaterials (Basel) ; 13(18)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37764529

RESUMO

The increasing use of graphene oxide (GO) will result in its release into the environment; therefore, it is essential to determine its final fate and possible metabolism by organisms. The objective of this study was to assess the possible role of the aryl hydrocarbon receptor (AhR)-dependent cytochrome P4501A (Cyp1A) detoxification activities on the catabolism of GO. Our hypothesis is that GO cannot initially interact with the AhR, but that after an initial degradation caused by other mechanisms, small fractions of GO could activate the AhR, inducing Cyp1A. The environmental pollutant benzo(k)fluoranthene (BkF) was used for the initial activation of the AhR in the rainbow trout (Oncorhynchus mykiss) cell line RTL-W1. Pre-, co-, and post-exposure experiments with GO were performed and Cyp1A induction was monitored. The strong stimulation of Cyp1A observed in cells after exposure to GO, when BkF levels were not detected in the system, suggests a direct action of GO. The role of the AhR was confirmed by a blockage of the observed effects in co-treatment experiments with αNF (an AhR antagonist). These results suggest a possible role for the AhR and Cyp1A system in the cellular metabolism of GO and that GO could modulate the toxicity of environmental pollutants.

15.
Chemosphere ; 310: 136894, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36265710

RESUMO

The bioaccumulation potential of spherical and rod-shaped CuO nanomaterials (NMs) was assessed in rainbow trout (Oncorhynchus mykiss) exposed via water and diet following the OECD Test Guideline No. 305. Fish were exposed via diet to both NMs at concentrations of 70 and 500 mg Cu/kg for 15 days, followed by 44 days of depuration. For water-borne exposure, only the rod-shaped CuO NMs were tested at 0.08 and 0.8 mg Cu/L for 28 days, followed by 14 days of depuration. The concentration of Cu was determined in fish whole body to derive biomagnification and bioconcentration factors (BMF and BCF). Different tissues were sampled to investigate the total Cu biodistribution and target organs as well as the particle number-based bioaccumulation of CuO NMs. Estimated BMF and BCF values were below the thresholds of concern. However, shape and route influenced depuration. Following dietary exposure, there was a higher depuration of Cu from fish exposed to the rod-shaped compared to the spherical CuO NMs. A higher depuration was also observed for rod-shaped CuO NMs following the dietary exposure compared the aqueous one. Despite the much higher dietary exposure concentrations of rod-shape CuO NMs, similar Cu body burdens were reached via water. Cu was found in particulate form in different tissues. Although these NMs had a low bioaccumulation potential, differences in distribution and elimination patterns of Cu were observed depending on the exposure route and particle shape. Careful consideration of the most relevant exposure route is needed when designing a bioaccumulation experiment for testing NMs.


Assuntos
Nanoestruturas , Oncorhynchus mykiss , Poluentes Químicos da Água , Animais , Bioacumulação , Distribuição Tecidual , Poluentes Químicos da Água/análise , Cobre , Água
16.
Toxins (Basel) ; 14(5)2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35622562

RESUMO

The use of plant-based fish feed may increase the risk of contamination by mycotoxins. The multiresidue analysis of mycotoxins in fish feed presents many difficulties due to the complexity of the matrix, the different characteristics of the compounds, and their presence in highly different concentration levels. The aim of this study was to develop a selective, sensitive, and efficient analytical method for the simultaneous determination of 15 mycotoxins (regulated and emerging mycotoxins) in aquaculture feed by LC-MS/MS. Sample extraction was performed with ultrasonic assistance, and different cleanup strategies were evaluated. The optimized method was composed by ultrasound-assisted extraction (two cycles, 55 °C, 20 min), followed by cleanup using a Captiva EMR Lipid cartridge. Then, nine commercial samples of aquaculture fish feed were analyzed. Eight of the 15 target mycotoxins were detected in the samples. Results showed that two enniatins (EENB and ENNB1), beauvericin, and fumonisin B2 were detected in all samples. These results show the multi-mycotoxin contamination of fish feed, highlighting the need to improve current knowledge on the occurrence and toxicity of mycotoxins in fish feed, mainly the emerging ones.


Assuntos
Micotoxinas , Animais , Aquicultura , Cromatografia Líquida , Contaminação de Medicamentos , Espectrometria de Massas em Tandem
17.
Eur J Hosp Pharm ; 28(6): 346-349, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-32788403

RESUMO

A 29-year-old African woman with active adult-onset Still's disease (AOSD) that developed at the end of 2018 presented to our hospital in September 2019 with pleuritic right-sided pain and respiratory insufficiency of almost a month's duration, which had failed to respond to high-dose corticosteroid and antibiotic treatment. A thoracic CT revealed right pleural effusion, multiple consolidations and pulmonary collapse. Besides pulmonary symptoms, the patient had arthralgia, fever, a salmon-coloured rash, leucocytosis and rising inflammatory markers. After an AOSD flare diagnosis was established, intravenous methylprednisolone and painkillers were administered. Due to the severity of the pleural effusion and the lack of response to previous treatments, subcutaneous anakinra was started. Two days after the first dose the patient had almost fully recovered. The success of this case points out the potential effectiveness of anakinra in the prevention of a pulmonary failure and the treatment of a severe intermittent polycyclic pattern of AOSD.


Assuntos
Doenças Pulmonares Intersticiais , Doença de Still de Início Tardio , Adulto , Feminino , Humanos , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doença de Still de Início Tardio/complicações , Doença de Still de Início Tardio/diagnóstico , Doença de Still de Início Tardio/tratamento farmacológico
18.
Toxins (Basel) ; 13(8)2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34437452

RESUMO

In the last decades, the aquaculture industry has introduced plant-based ingredients as a source of protein in aquafeeds. This has led to mycotoxin contaminations, representing an ecological, health and economic problem. The aim of this study was to determine in the RTgill-W1 fish cell line the toxicity of fifteen mycotoxins of common occurrence in aquafeeds. To identify the most sensitive endpoint of toxicity, the triple assay was used. It consisted of three assays: alamarBlue, Neutral Red Uptake and CFDA-AM, which revealed the mitochondrial activity, the lysosomal integrity and the plasma membrane integrity, respectively. Most of the assayed mycotoxins were toxic predominantly at lysosomal level (enniatins, beauvericin, zearalenone, ochratoxin A, deoxynivalenol (DON) and its acetylated metabolites 15-O-acetyl-DON and 3-acetyl-DON). Aflatoxins B1 and B2 exerted the greatest effects at mitochondrial level, while fumonisins B1 and B2 and nivalenol were not toxic up to 100 µg/mL. In general, low toxicity was observed at plasma membrane level. The vast majority of the mycotoxins assayed exerted a pronounced acute effect in the fish RTgill-W1 cell line, emphasizing the need for further studies to ascertain the impact of mycotoxin contamination of fish feeds in the aquaculture industry and to establish safe limits in aquafeeds.


Assuntos
Ração Animal/análise , Ração Animal/microbiologia , Aquicultura , Citotoxinas/análise , Citotoxinas/toxicidade , Peixes/crescimento & desenvolvimento , Micotoxinas/análise , Micotoxinas/toxicidade , Animais , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos
19.
MethodsX ; 8: 101413, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34430308

RESUMO

The first step of nanomaterial accumulation in the aquatic environment is the uptake of particulate material. For substances with very low water solubility, exposure via water may be of limited relevance in comparison to the dietary route. The OECD Test Guideline 305 for bioaccumulation testing in fish using dietary exposure recommends to add substances to fish food following methodologies normally used in aquaculture (e.g. with a corn or fish oil vehicle). The feasibility of using such an approach for the testing of manufactured nanomaterials (MNs), due to their unique physical characteristics and solubility, needs to be investigated. In this study an easy, cost-effective method to prepare metal oxide nanoparticle (NP) spiked feed to give the required dietary exposure concentration to fish is described. Metal oxide NP (CeO2,TiO2 and ZnO) dispersions were prepared in oil (sunflower or olive oil) and used to soak fish feed pellets. NP surface deposition and homogeneity of distribution were analysed and confirmed. Discrepancies between nominal and measured concentrations highlighted the need to measure the achieved concentration in MN-spiked feed. The present method provides stable concentrations for bioaccumulation testing of MNs in fish through the dietary route. A method for•Fish feed preparation using nanomaterial-oil suspensions.•Homogenous spiking of nanomaterials on feed.•Nanomaterials stably maintained on feed immersed in water until eaten by fish.

20.
Foods ; 9(11)2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33218048

RESUMO

Zearalenone (ZEA) is produced in cereals by different species of Fusarium, being a non-steroidal estrogenic mycotoxin. Despite having a low acute toxicity, ZEA strongly interferes with estrogen receptors. Gamma-radiation has been investigated to eliminate mycotoxins from food and feed, showing promising results. The present study aims to investigate the gamma-radiation effect on ZEA at different moisture conditions and to evaluate the cytotoxicity and estrogenicity of the irradiated ZEA. Different concentrations of dehydrated ZEA and aqueous solutions of ZEA were exposed to gamma-radiation doses ranging from 0.4 to 8.6 kGy and the mycotoxin concentration determined after exposure by high performance liquid chromatography (HPLC) with fluorescence detection. Following this, the cytotoxicity of irradiated samples was assessed in HepG2 cells, by measuring alterations of metabolic activity, plasma membrane integrity and lysosomal function, and their estrogenicity by measuring luciferase activity in HeLa 9903 cells. Gamma-radiation was found to be effective in reducing ZEA, with significant increases in degradation with increased moisture content. Furthermore, a reduction of cytotoxicity with irradiation was observed. ZEA estrogenicity was also increasingly reduced with increasing radiation doses, but mainly in aqueous solutions. These results suggest reduction of ZEA levels and of its toxicity in food and feed commodities may be achieved by irradiation.

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