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1.
NanoImpact ; 29: 100447, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36563784

RESUMO

Tests using algae and/or cyanobacteria, invertebrates (crustaceans) and fish form the basic elements of an ecotoxicological assessment in a number of regulations, in particular for classification of a substance as hazardous or not to the aquatic environment according to the Globally Harmonised System of Classification and Labelling of Chemicals (GHS-CLP) (GHS, 2022) and the REACH regulation (Registration, Evaluation, Authorisation and Restriction of Chemicals, EC, 2006). Standardised test guidelines (TGs) of the Organisation for Economic Co-operation and Development (OECD) are available to address the regulatory relevant endpoints of growth inhibition in algae and cyanobacteria (TG 201), acute toxicity to invertebrates (TG 202), and acute toxicity in fish (TG 203). Applying these existing OECD TGs for testing two dimensional (2D) graphene nanoforms may require more attention, additional considerations and/or adaptations of the protocols, because graphene materials are often problematic to test due to their unique attributes. In this review a critical analysis of all existing studies and approaches to testing used has been performed in order to comment on the current state of the science on testing and the overall ecotoxicity of 2D graphene materials. Focusing on the specific tests and available guidance's, a complete evaluation of aquatic toxicity testing for hazard classification of 2D graphene materials, as well as the use of alternative tests in an integrated approach to testing and assessment, has been made. This information is essential to ensure future assessments generate meaningful data that will fulfil regulatory requirements for the safe use of this "wonder" material.


Assuntos
Grafite , Organização para a Cooperação e Desenvolvimento Econômico , Animais , Testes de Toxicidade/métodos , Peixes , Invertebrados
2.
Chemosphere ; 309(Pt 1): 136636, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36181847

RESUMO

Nanobiomaterials (NBMs) are nanostructured materials for biomedical applications that can reach aquatic organisms. The short and long-term effects of these emerging contaminants are unknown in fish. The RTgill-W1 cell line has been proposed as a model to predict the acute toxicity of chemicals to fish (OECD Test Guideline nº 249). We assessed the applicability of this cell line to study the short and long-term toxicity of 15 NBMs based on hydroxyapatites (HA), lipid (LSNP/LNP), gold, iron oxide, carbon, poly l-Lactide acid (PLLA) fibers with Ag and poly (lactide-co-glycolide) acid. Two more rainbow trout cell lines (RTL-W1, from liver, and RTS-11, from spleen) were exposed, to identify possible sensitivity differences among cells. Exposures to a range of concentrations (0.78-100 µg/mL) lasted for 24 h. Additionally, the RTgill-W1 was used to perform long-term (28 d exposure) and recovery (14 d exposure/14 d recovery) assays. Cells were exposed to the 24 h-IC20 and/or to 100 µg/mL. A triple cytotoxicity assay was conducted. After 24 h, only PLLA Fibers-Ag showed cytotoxicity (IC50 < 100 µg/mL). However, the NBMs in general provoked concentration-dependent effects after long-term exposures, except the LSNPs. A recovery of viability was only observed for AuNPs, AuNRods, Fe3O4PEG-PLGA, MgHA-Collag_Scaffolds, Ti-HA and TiHA-Alg NPs.These results evidenced the need to test the long-term toxicity of NBMs and showed differences in cytotoxicity probably associated to different mechanisms of toxic action. The RTgill-W1 was useful to screen short and long-term toxicities of NBMs and appears as a promiseful model to assess possible toxicity of NBMs in fish.


Assuntos
Nanopartículas Metálicas , Oncorhynchus mykiss , Animais , Ouro/metabolismo , Linhagem Celular , Oncorhynchus mykiss/metabolismo , Carbono/metabolismo , Hidroxiapatitas/metabolismo , Lipídeos
3.
Aquat Toxicol ; 242: 106020, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34844051

RESUMO

Biocidal substances and their environmental relevant metabolites are highly toxic for fish. However, an important scarcity of toxicity data for metabolites is recognised. This article provides new data about the toxicity to fish of these compounds and evaluates the potential use of fish cell lines as screening tools to assess the acute toxicity of these compounds in fish. To this aim, acute toxicity of 7 substances was tested in Oncorhynchus mykiss (OECD TG203) and cytotoxicity of 16 substances was assessed in fish cell lines from two species; Poeciliopsis lucida (PLHC-1) and O. mykiss (RTH-149, RTG-2 and RTgill-W1) performing three cytotoxicity tests: Alamar-Blue, 5-carboxyfluorescein diacetate, acetoxymethyl ester and Neutral Red Uptake. Additionally, in vitro and in vivo data from the LIFE-COMBASE database were included in a dataset finally comprising 33 biocides and 14 metabolites. Hazard data were categorized into 4 toxicity groups, according to the intervals established in Regulation (EC) 1272/2008. Finally, the Spearman correlation test was performed and coincidences between in vitro-in vivo data established. In vitro and in vivo results revealed a high positive correlation, with a complete coincidence for 56.5% of the substances, a 2% of false positives (non-toxic in vivo) and a 13% of false negatives (toxic in vivo) for the 4 toxicity categories. However, when results were grouped in toxic or non-toxic coincidence was obtained for 85% of the substances. In conclusion, although fish denote a greater sensitivity, the use of at least two fish cell lines and three cytotoxicity endpoints appear to be valid approaches for fish acute toxicity screening of biocides and their metabolites.


Assuntos
Ciprinodontiformes , Desinfetantes , Oncorhynchus mykiss , Testes de Toxicidade Aguda , Poluentes Químicos da Água , Animais , Linhagem Celular , Poluentes Químicos da Água/toxicidade
4.
Food Chem Toxicol ; 127: 288-297, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30716354

RESUMO

The toxicity of mycotoxins is well recognized in mammals, but their effects on fish have received less attention. Moreover, in the last years several studies have reported that some mycotoxins may act as endocrine disruptors. The aim of this study was to determine the cytotoxic effects and endocrine activities of three mycotoxins: beauvericin, deoxynivalenol and ochratoxin-A. Cytotoxicity in two fish hepatoma and one mammalian hepatoma cell lines was determined by the AlamarBlue, Neutral Red Uptake and CFDA-AM assays. For the assessment of androgenic, estrogenic and thyroidal agonistic/antagonistic effects three cell lines stably expressing luciferase as reporter gene under the control of hormone receptors were used. Results showed that both fish and mammalian cell lines were very sensitive to the mycotoxins tested. OTA was the least toxic mycotoxin and DON and BEA showed similar acute toxicity. None of the three mycotoxins tested presented agonistic effects at the receptors studied, but all of them showed strong antagonistic effect at the thyroid receptor. BEA showed a weak antagonistic effect at the androgen receptor and OTA produced a biphasic dose-response curve at the estrogen receptor. The data obtained in this work are of high interest for aquaculture industries and for regulators.


Assuntos
Depsipeptídeos/toxicidade , Disruptores Endócrinos/toxicidade , Ocratoxinas/toxicidade , Oncorhynchus mykiss , Tricotecenos/toxicidade , Animais , Linhagem Celular , Concentração Inibidora 50 , Ratos , Receptores Androgênicos/efeitos dos fármacos , Receptores de Estrogênio/efeitos dos fármacos
5.
Toxicol In Vitro ; 50: 305-317, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29660445

RESUMO

The current wide use of manufactured nanomaterials (MNs) is leading to the release of nanoparticles (NPs) to water bodies. Aquatic organisms, including fish, are exposed to low concentrations of NPs for long periods of time being necessary to develop laboratory toxicity tests reflecting realistic conditions. Additionally, today there is a demand of in vitro assays respecting the 3Rs principle. Thus, the main aim of this work was to stablish an in vitro tool for the assessment of long-term NPs ecotoxicity. Considering the key role of liver in detoxification, a rainbow trout liver cell line, RTL-W1, was used. CuO NPs were chosen to validate this tool taking into account their important production level. Cells were exposed for 21 days to 25 or 100 µg CuO NPs/ml. Every seven days cells were split and one fourth of them transferred to a new plate with appropriate concentrations of NPs in culture medium. Lower concentrations of CuO NPs did not cause any deleterious effect, whereas higher concentrations led to significant mortality after 14 days and to the intracellular accumulation of Cu particles. Identical results were observed in cells exposed to CuSO4 at the same Cu concentrations. Therefore, the observed toxic effects might be mainly due to Cu2+ ions.


Assuntos
Nanoestruturas/toxicidade , Testes de Toxicidade/métodos , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cobre/toxicidade , Sulfato de Cobre/toxicidade , Oncorhynchus mykiss
6.
Chemosphere ; 201: 388-398, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29529566

RESUMO

Endocrine disruptors (EDs) are natural or man-made chemicals that can affect the health of organisms by interfering with their normal hormonal functions. Many of these substances can cause their effects at very low doses and, considering the key role played by the endocrine system on development, organisms in early phases of growth (foetal, childhood, puberty) are especially sensitive to the action of EDs. In addition, when combined, they can show additive, antagonistic and synergistic activities. Taking all this into account it is essential to determine the presence of this kind of compounds in drinking water. Thus the main aim of the present study was to monitor the presence of substances with suspected or known endocrine activity in drinking water of the Madrid Region (MR) (Central Spain) and determine possible estrogenic, androgenic, or thyroidal activities. Water samples were collected at different times from a number of supply points that received water from reservoirs or rivers. The sampling point with the highest concentration of the analysed substances (up to 30 compounds) was DW1 (1203 ng L-1). This sampling point receives water from a drinking water treatment plant (DWTP) that serves the population from the south of the MR with treated water from the Tajuña River. DW2 was the second point with the highest concentration of the analysed substances (1021 ng L-1). DW2 receives water from one of the reservoirs in the north of the MR. The highest daily concentrations detected corresponded to the flame retardant Tris (2-chloroethyl)phosphate (TCEP) (266.55 ng L-1) and to the nonylphenol diethoxylate (188.57 ng L-1) at points DW1 and DW4, respectively, both of which are supplied with treated river water. None of the water samples exhibited androgenic, oestrogenic, or thyroidal activities in in vitro assays based on cells stably transfected with the receptors of interest and luciferase as reporter gene. These results demonstrate that water quality in the MR is high and does not present a health risk for the population, although the concentrations of some substances justify the need for local authorities to continually monitor the presence of these contaminants in order to implement any corrective measures if necessary.


Assuntos
Água Potável/química , Disruptores Endócrinos/análise , Monitoramento Ambiental/métodos , Qualidade da Água/normas , Androgênios/análise , Água Potável/efeitos adversos , Estrogênios/análise , Humanos , Espanha , Hormônios Tireóideos/análise , Poluentes Químicos da Água/análise , Abastecimento de Água/normas
7.
Regul Toxicol Pharmacol ; 90: 297-307, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28966106

RESUMO

Risk assessment of engineered nanomaterials (ENMs) is being hindered by the sheer production volume of these materials. In this regard, the grouping and ranking of ENMs appears as a promising strategy. Here we sought to evaluate the usefulness of in vitro systems based on fish cell lines for ranking a set of ENMs on the basis of their cytotoxicity. We used the topminnow (Poeciliopsis lucida) liver cell line (PLHC-1) and the rainbow trout (Oncorhynchus mykiss) fibroblast-like gonadal cell line (RTG-2). ENMs were obtained from the EU Joint Research Centre repository. The size frequency distribution of ENM suspensions in cell culture media was characterized. Cytotoxicity was evaluated after 24 h of exposure. PLHC-1 cells exhibited higher sensitivity to the ENMs than RTG-2 cells. ZnO-NM was found to exert toxicity mainly by altering lysosome function and metabolic activity, while multi-walled carbon nanotubes (MWCNTs) caused plasma membrane disruption at high concentrations. The hazard ranking for toxicity (ZnO-NM > MWCNT ≥ CeO2-NM = SiO2-NM) was inversely related to the ranking in size detected in culture medium. Our findings reveal the suitability of fish cell lines for establishing hazard rankings of ENMs in the framework of integrated approaches to testing and assessment.


Assuntos
Ecotoxicologia/métodos , Nanotubos de Carbono/toxicidade , Dióxido de Silício/toxicidade , Testes de Toxicidade/métodos , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Peixes , Hepatócitos , Lisossomos/efeitos dos fármacos , Medição de Risco/métodos , Dióxido de Silício/farmacocinética
8.
Artigo em Inglês | MEDLINE | ID: mdl-27544301

RESUMO

Among the nanomaterials currently in commercial products, those based on silver are the most used, and so there is a high probability that silver nanoparticles (AgNPs) will be released into aquatic environments where they could adversely affect aquatic organisms, including fish. Taking this into account, the aim of the present work was to characterize in depth the mechanisms underlying the toxic action of AgNPs using fish cell lines, determining specifically the contribution of alterations in cellular structures and oxidative stress time course to the cytotoxicity of AgNPs. Since liver plays a key role in detoxification, the hepatoma cell line PLHC-1 was used. Exposure to AgNPs (NM-300K, obtained from the Joint Research Centre Repository) caused alterations at the lysosomal and mitochondrial levels at lower concentrations than those that disrupted plasma membrane (evaluated by means of neutral red, alamarBlue, and 5-carboxyfluorescein diacetate, acetoxymethyl ester assays respectively). AgNO3, used as a control Ag+ ion source, produced similar cytotoxic effects but at lower concentrations than AgNPs. Both silver forms caused oxidative disruption but the initial response was delayed in AgNPs until 6h of exposure. Transmission electron microscopy analysis also evidenced the disruption of mitochondrial structures in cells exposed to cytotoxic concentrations of both forms of silver. At non-cytotoxic concentrations, AgNPs were detected inside the nucleoli and mitochondria, thereby pointing to long-term effects. The present work evidences the mutual interaction between the induction of oxidative stress and the alterations of cellular structures, particularly mitochondria, as cytotoxicity mechanisms not exclusively associated to NPs.


Assuntos
Cyprinidae/metabolismo , Hepatócitos/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Mitocôndrias Hepáticas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Prata/toxicidade , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Hepatócitos/metabolismo , Hepatócitos/ultraestrutura , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/ultraestrutura , Espécies Reativas de Oxigênio/metabolismo , Nitrato de Prata/toxicidade , Fatores de Tempo
9.
Fish Shellfish Immunol ; 38(1): 166-74, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24657316

RESUMO

Thyroid hormones are involved in modulating the immune system in mammals. In contrast, there is no information on the role played by these hormones in the immune system of teleost fish. Here we provide initial evidence for the presence of active thyroid signaling in immune organs and cells of teleosts. We demonstrate that immune organs (head kidney and spleen) and isolated leukocytes (from head kidney and peripheral blood) of the rainbow trout (Oncorhynchus mykiss) express both thyroid receptor α (THRA) and ß (THRB). Absolute mRNA levels of THRA were significantly higher than those of THRB. THRA showed higher expression in immune organs and isolated immune cells compared to the reference organ, liver, while THRB showed the opposite. In vivo exposure of trout to triiodothryronine (T3) or the anti-thyroid agent propylthiouracil (PTU) altered THR expression in immune organs and cells. Effect of T3 and PTU over the relative expression of selected marker genes of immune cell subpopulations was also studied. Treatments changed the relative expression of markers of cytotoxic, helper and total T cells (cd4, cd8a, trb), B lymphocytes (mIgM) and macrophages (csf1r). These findings suggest that the immune system of rainbow trout is responsive to thyroid hormones.


Assuntos
Rim Cefálico/fisiologia , Oncorhynchus mykiss/fisiologia , Transdução de Sinais/fisiologia , Baço/fisiologia , Glândula Tireoide/fisiologia , Animais , Regulação da Expressão Gênica/imunologia , Receptores da Tireotropina/genética , Receptores da Tireotropina/metabolismo
10.
Sci Total Environ ; 472: 630-41, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24317169

RESUMO

Among the many chemicals found in avian manure, endocrine disruptors (EDs), of natural or anthropogenic origin, are of special environmental concern. Nowadays, an increasing amount of estrogens is being released into the environment via the use of manure to fertilize agricultural land. While most research in this field has focused on estrogenic phenomena, little is known about alterations related to other endocrine systems, such as the thyroidal one. Here we simultaneously assessed the potential estrogenic and thyroidal activity of poultry and broiler litter manure using in vitro approaches based on estrogen receptor (Er) and thyroid receptor (Tr) transactivation assays. In addition, leaching experiments were performed to assess whether the EDs present in the manure pass through a soil column and potentially reach the groundwater. Manure from four broiler and four poultry farms was collected in two sampling campaigns carried out in two seasons (fall and spring). Extracts from broiler and poultry manure exhibited strong thyroidal activity. Only poultry manure showed estrogenic activity, which is consistent with the low levels of estrogens expected in hatchlings. Leakage experiments were performed in columns with two kinds of arable soils: sandy and loamy. No estrogenicity or thyroidal activity was detectable in soils treated with the manure or in the corresponding leachates. These results indicate that substances with estrogenic or thyroidal activity were degraded in the soil under our experimental conditions. However, the long-term effects associated with the constant and intensive application of manure to agricultural land in some regions require further research.


Assuntos
Criação de Animais Domésticos , Disruptores Endócrinos/análise , Poluentes Ambientais/análise , Estrogênios/análise , Estrona/análise , Esterco/análise , Animais , Bioensaio , Disruptores Endócrinos/toxicidade , Monitoramento Ambiental , Poluentes Ambientais/toxicidade , Estrogênios/toxicidade , Estrona/toxicidade , Aves Domésticas
11.
Arch Environ Contam Toxicol ; 65(3): 567-74, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23619767

RESUMO

The effect of orally administered atrazine (25 or 100 mg/kg on days 0, 5, and 10 of the experiment) was studied in European quail (Coturnix coturnix coturnix) on four non-destructive biomarkers: fecal porphyrins, blood glutathione-S-transferase, glutathione reductase, reduced glutathione, and malondialdehyde (MDA). Uroporphyrin I (UPI) and coproporphyrins I and III (CPIII) were the main porphyrins detected in feces. The lowest dose of ATZ caused a significant (P < 0.05) increase in UPI and CPIII at day 5, and the highest dose of ATZ caused an induction of CPI and a significant (P < 0.05) decrease in MDA levels at day 30.


Assuntos
Atrazina/toxicidade , Coturnix/metabolismo , Exposição Ambiental , Herbicidas/toxicidade , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Biomarcadores/metabolismo , Cromatografia Líquida de Alta Pressão , Fezes/química , Feminino , Fluorometria , Glutationa/sangue , Glutationa Redutase/sangue , Glutationa Transferase/sangue , Malondialdeído/sangue , Porfirinas/metabolismo , Espectrofotometria
12.
Tissue Cell ; 45(3): 159-74, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23305652

RESUMO

Despite its wide use in toxicology, a detailed characterization of RTL-W1 cell line lagged behind leaving ambiguities about its cell origin. We aimed to better characterize the line regarding cell phenotype and tumorigenic state. We studied RTL-W1 cells in monolayers and in (4-22-week-old) aggregates considering: (a) morphology (light and electron microscopy); (b) immunophenotype using AE1/AE3, vimentin, Cam5.2, CK7 and CK19 and e-cadherin antibodies and (c) growth behavior. RTL-W1 organelle content is constituted basically by mitochondria and abundant free ribosomes, with no (cytochemically) detectable peroxisomes and lysosomes. Immunocytochemistry showed a strong marking for AE1/AE3 and vimentin (in a cell subset). Since AE1/AE3 stained biliary epithelial ducts in trout liver, and considering the morphological characteristics and long term culture, RTL-W1 cells seem more similar to bile preductular epithelial cells (considered as stem cells in teleost liver). Also, we observed abnormal nuclear features described for both malignant cell lines and stem cells, so we could not conclude about tumorigenicity. Cell aggregates had signs of hepatocytic differentiation, such as the development of RER and microvillus-like projections into intercellular spaces. The morphological resemblance to the original tissue suggests that aggregates could have an added value in metabolic as well as in cell-to-cell interaction studies.


Assuntos
Linhagem Celular/citologia , Fígado/citologia , Fígado/crescimento & desenvolvimento , Animais , Caderinas/metabolismo , Caderinas/ultraestrutura , Agregação Celular , Comunicação Celular , Linhagem Celular/imunologia , Linhagem Celular/ultraestrutura , Citocromo P-450 CYP1A1/metabolismo , Hepatócitos/metabolismo , Hepatócitos/ultraestrutura , Fígado/imunologia , Fígado/ultraestrutura , Oncorhynchus mykiss/crescimento & desenvolvimento , Oncorhynchus mykiss/imunologia
13.
Talanta ; 100: 90-106, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23141316

RESUMO

This work focuses on a revision of analytical methodologies for the determination of industrial chemicals that have an endocrine-disrupting effect on food commodities. These food commodities have been divided into two major categories: crops and food of animal origin. The reviewed methods have been commented on in terms of sample preparation, analytical methods, and the occurrence of the studied compounds.


Assuntos
Disruptores Endócrinos/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Animais , Sinergismo Farmacológico , Disruptores Endócrinos/farmacologia , Humanos , Indústrias , Praguicidas/análise , Praguicidas/farmacologia
14.
Anal Bioanal Chem ; 404(9): 2749-63, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22875538

RESUMO

This article presents a dose-response study of the effects of two types of third-generation (G3) and fourth-generation poly(amidoamine) (PAMAM) dendrimers on two cell lines (RTG-2 and H4IIE) by in vitro cytotoxicity assays with 3-(4,5-dimethylthizol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), neutral red uptake (NRU), and lactate dehydrogenase (LDH) assays. We particularly investigated the potential cytotoxic effect of positive surface charge, which a cationic amino-terminated PAMAM dendrimer can display, on the marked ability of PAMAM dendrimers to cross the cell membrane compared with PAMAM dendrimers functionalized with chains of N-(2-hydroxydodecyl). Quantification of dose-response effects was performed by use of mass spectrometry analysis. The analytical method using liquid chromatography-hybrid quadrupole/time-of-flight mass spectrometry that we developed allowed characterization of defective dendrimers instead of "ideal structures." Identification was based on accurate mass measurement, assignment of elemental composition, and the fully resolved (13)C/(12)C isotopic clusters of the multiply charged ions of PAMAM dendrimers. Validation of the liquid chromatography-mass spectrometry method made possible reliable and reproducible quantification of the extracellular and intracellular concentration of dendrimers at a micromolar level (limits of detection from 0.14 to 1.34 µM and from 0.43 to 1.82 µM in standard and culture medium, respectively). A higher cytotoxicity was found with the H4IIE cell line for surface-modified PAMAM dendrimers. The LDH assay was significantly more sensitive than the MTT and NRU assays, with half-maximal inhibitory concentrations (IC(50)) of 12.96 and 38.31 µg mL(-1) for surface-modified G3 and G4 dendrimers, respectively. No cytotoxic effects, in terms of IC(50), of amino-terminated PAMAM dendrimers were observed on both H4IIE and RTG-2 cells when the concentration was below 500 µg mL(-1) for G3 and G4 dendrimers.

15.
J Fish Biol ; 81(1): 270-87, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22747818

RESUMO

Two rainbow trout Oncorhynchus mykiss fish farms were repeatedly sampled in order to observe the variability of ethoxyresorufin-O-deethylase (EROD) activity and of related genes in the liver. Fish coming from fish farm A exhibited EROD levels that could be considered as basal according to the scientific literature, however, EROD activity in fish coming from fish farm B was significantly increased. This was accompanied by augmented aryl hydrocarbon receptor (ahr) and cytochrome P4501A (cyp1A) messenger RNA expression and reduced oestrogen receptor (er) and vitellogenin (vtg) transcription. Only sediment extracts from the entry channel of fish farm B induced EROD activity in O. mykiss cultured cells, however, this induction could not be explained by the levels of polyaromatic hydrocarbons (PAH) and polychlorinated biphenyls (PCB) measured in the sediments. The results of this study point out that O. mykiss cultured in fish farms could be used as sentinels for indication of pollution. In this particular work, however, no conclusive evidence has been found for a relationship between the presence of PAHs and PCBs and the observed EROD induction.


Assuntos
Citocromo P-450 CYP1A1/metabolismo , Monitoramento Ambiental/métodos , Oncorhynchus mykiss/genética , Animais , Aquicultura , Biomarcadores/metabolismo , Linhagem Celular , Citocromo P-450 CYP1A1/genética , Feminino , Fígado/enzimologia , Fígado/metabolismo , Oncorhynchus mykiss/metabolismo , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Estrogênio/metabolismo , Vitelogeninas/metabolismo , Poluentes Químicos da Água/análise
16.
Toxicol In Vitro ; 26(6): 888-96, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22554435

RESUMO

Two cerium oxide nanoparticles (CeO(2) NPs) and one micro-sized CeO(2) particle were thoroughly characterized in their pristine form, in water and in cell culture medium. The particles were tested for cytotoxicity to the H4IIE rat hepatoma cell line or the RTG-2 rainbow trout gonadal cell line by means of four standard cytotoxicity assays. Nominal concentrations were verified by inductively coupled plasma mass spectrometry (ICP-MS) and methods were assessed for their suitability to detect reliably adverse effects due to particle exposure. All three particles showed aggregation in water and media. In the H4IIE cell line, the MTT cytotoxicity test revealed that negative effects could be observed for the CeO(2) NPs after 24h and for all particles after 72h of exposure, making the effects size, concentration and time dependent. No negative effect for the concentrations tested was detected for the remaining three assays and the RTG-2 cell line, making the MTT assay and the H4IIE cell line an appropriate system to assess adverse effects of CeO(2) NPs. A verification of the nominal concentration through ICP-MS revealed that there was a discrepancy between nominal and measured concentration depending on concentration and particle tested. Interferences of particles with assays were found to be present and need to be taken into consideration.


Assuntos
Cério/toxicidade , Nanopartículas/toxicidade , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , L-Lactato Desidrogenase/metabolismo , Vermelho Neutro/metabolismo , Oncorhynchus mykiss , Tamanho da Partícula , Ratos , Sais de Tetrazólio/metabolismo , Tiazóis/metabolismo , Testes de Toxicidade
17.
Can J Urol ; 15(4): 4186-90, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18706150

RESUMO

Spinal epidural abscess is an infectious disorder with high morbidity and mortality rates, which is often associated with delayed diagnosis. We report a case of a 73-year-old man with cervical pyogenic spondylodiscitis complicated with epidural abscess following a prostatic biopsy. Clinical presentation included fever, malaise, neck rigidity in all axes, minor paresis of the right arm, and gait ataxia. A cervical vertebral magnetic resonance imaging (MRI) scan showed pyogenic spondylodiscitis with an epidural abscess. Blood, urine, and cerebrospinal fluid cultures were sterile. The patient was treated with intravenous vancomycin, metronidazole, and ceftazidime for 4 weeks, and was discharged from the hospital and treated with oral cloxacillin, metronidazole, and cefixime for another 2 weeks. His neurological symptoms disappeared completely, and he walked normally, without support. It is important for clinicians to be alert to symptoms accompanying back pain following a prostatic biopsy and to consider the possibility of a diagnosis of spinal abscess.


Assuntos
Biópsia/efeitos adversos , Vértebras Cervicais , Abscesso Epidural/etiologia , Doenças Prostáticas/patologia , Idoso , Antibacterianos/uso terapêutico , Diagnóstico Diferencial , Discite/diagnóstico , Discite/tratamento farmacológico , Discite/etiologia , Abscesso Epidural/diagnóstico , Abscesso Epidural/tratamento farmacológico , Humanos , Imageamento por Ressonância Magnética , Masculino , Tomografia Computadorizada por Raios X
18.
Toxicol In Vitro ; 21(7): 1307-10, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17521864

RESUMO

The classical pathway for induction of cytochrome P4501A (CYP1A) by xenobiotics is ligand binding to the aryl hydrocarbon receptor (AhR). However, several studies with mammalian cell systems point out a range of xenobiotics including imidazole derivatives, which are able to activate CYP1A through non-classical mechanisms. The objective of the present work is to compare induction of CYP1A (determined at the catalytic level as 7-ethoxyresorufin-O-deethylase, EROD) in rainbow trout (Oncorhynchus mykiss) hepatocytes by the prototypic AhR ligand, beta-naphthoflavone (betaNF), and by the imidazole derivative, 1-phenylimidazole (PIM). PIM was able to induce EROD activity although its potency was clearly lower than that of betaNF. In order to assess the relative importance of classical AhR ligand binding and alternative signaling pathways in CYP1A induction by PIM, co-exposure experiments with the partial AhR antagonist alpha-naphthoflavone (alphaNF) or with inhibitors of protein kinase C (staurosporine) and tyrosine kinases (genistein, herbimicine) were performed. alphaNF and herbimicin provoked a decrease of EROD induction both by betaNF and PIM, whereas staurosporine and genistein remained without effect. The overall similarities in the response of betaNF and PIM to the various inhibitors suggest that both compounds, in apparent contrast to the behaviour of some other imidazole derivatives, induce CYP1A following similar mechanisms.


Assuntos
Citocromo P-450 CYP1A1/efeitos dos fármacos , Imidazóis/farmacologia , Receptores de Hidrocarboneto Arílico/efeitos dos fármacos , beta-Naftoflavona/farmacologia , Animais , Citocromo P-450 CYP1A1/metabolismo , Indução Enzimática , Hepatócitos/metabolismo , Ligantes , Oncorhynchus mykiss , Proteína Quinase C/efeitos dos fármacos , Proteína Quinase C/metabolismo , Proteínas Tirosina Quinases/efeitos dos fármacos , Proteínas Tirosina Quinases/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais/efeitos dos fármacos
19.
Ansiedad estrés ; 12(2/3): 413-425, dic. 2006. tab
Artigo em Espanhol | IBECS | ID: ibc-74895

RESUMO

Según Mayer y Solovey (1997), para identificiar una nueva inteligencia dentro de la psicología los paos a seguir son: (a) definirla, (b) desarrollar una herrameinta para mediarla, (c) acreditar su independencia parcial o completa de inteliencias ya conocidas, y (d) demostrar que predice algún criterio real. Este artículo se ctra en los dos últimospasos. Para ellos presentamos dos trabjaos. El primero es una análisis de correlaciones de personalidad. Donde se prueba que sólo con médidas de ejecución, la IE es indipendiente d ela personaliad y del CI. En el segundo estudio se pone a prueba la validez predicta de la IE, mediante análisis de regresión por género, con criterios objetivos de adaptación escolar (frecuencia de comportamientos conflictivos, el rendimeinto academico y el numero de veces que h sido elegido como buen compañero)(AU)


According to Mayer and Salovey (197) for identify the new intelligence within the psychology we must to do: (a) to define it. (b) to develop a mean for measuring it, (c) to doument its partial or complete independence from known intelligences,a nd (d) to demonstrate that it predicts some real-world criteria. This paper is focused in bot third and fourth steps. So we present twos tudies. First stdy, we realize correlations between seeral measures of emotional itnelligence (EI), IQ and five Factor Model of personality. The outcomes confirm that only with performane measure of EI, this is independent of pesonality measures and IQ. Secnd study is an El predictive validity by menas of analyis of regression, differntiating for maes and females, under objective criteria of schol adaptation (frequency of conflictive behaviors at school, academic achieveent and the number of times that a scholar has been elected as good peer)(AU)


Assuntos
Humanos , Masculino , Feminino , Inteligência/classificação , Inteligência/fisiologia , Competência Mental/classificação , Competência Mental/psicologia , Inventário de Personalidade/estatística & dados numéricos , Inventário de Personalidade/normas , Testes de Personalidade/estatística & dados numéricos , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Testes de Inteligência/estatística & dados numéricos , Determinação da Personalidade/estatística & dados numéricos , Transtornos da Personalidade/epidemiologia , Transtornos da Personalidade/psicologia
20.
Aquat Toxicol ; 75(4): 306-15, 2005 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-16213605

RESUMO

Results from previous experiments directed to determine the effect of different nutritional factors or the effect of xenobiotics on hormonal control of reproduction, lead to the hypothesis that hormonal perturbations repeatedly observed in sea bass (Dicentrarchus labrax) broodstock feeding commercial diets could have been caused by the presence of aryl hydrocarbon receptor (AhR) ligands, such as dioxins, furans and polychlorinated biphenyls (PCBs) in the diet. To evaluate this hypothesis, dioxins and related compounds were analysed in liver of female sea bass fed with a commercial or with a natural diet consisting of trash fish (bogue, Boops boops), and concentrations of vitellogenin (VTG) and 17beta-estradiol (E2) were determined in plasma obtained previously in monthly samplings of these animals. As observed in other experiments, females fed with a commercial diet exhibited lower VTG and higher E2 plasma levels than females fed with the natural diet. In liver, sea bass fed with the commercial diet exhibited a profile clearly dominated by high-chlorinated dioxins while in fish fed with the natural diet this profile was dominated by low chlorinated furans. However, typical AhR ligands, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin showed no differences between groups or, as is the case of planar PCBs, showed higher concentrations in the liver of fish fed with the natural diet. These results do not permit to explain the observed hormonal alterations by a possible antiestrogenic effect caused by dioxins and related compounds.


Assuntos
Ração Animal/análise , Bass/metabolismo , Dieta , Estradiol/sangue , Hidrocarbonetos Clorados/análise , Fígado/química , Vitelogeninas/sangue , Análise de Variância , Animais , Aquicultura , Bass/sangue , Isótopos de Carbono , Cromatografia Gasosa-Espectrometria de Massas , Espanha
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