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1.
J Toxicol Environ Health A ; 84(22): 901-913, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34259612

RESUMO

The water produced (PW) by the petroleum industry is a potential contaminant to aquatic biota, due to its complex mixture that may contain polycyclic aromatic hydrocarbons (PAHs), organic chemical compounds, including benzene, toluene, ethylbenzene and xylene (BTEX), metals and other components that are known to be toxic. The aim of this investigation was to examine the acute toxicity produced by a PW sample in aquatic organisms Vibrio fischeri and Daphnia similis prior to and after 4 treatments using advanced oxidative processes such as photocatalysis, photoelectrocatalysis, ozonation and photoelectrocatalytic ozonation. Data demonstrated that exposure to PW was toxic to both organisms, as evidenced by reduced luminescence in bacterium Vibrio fischeri and induced immobility in Daphnia similis. After treatment of PW with 4 different techniques, the PW remained toxic for both tested organisms. However, photoelectrocatalysis was more efficient in decreasing toxicity attributed to PW sample. Therefore, data demonstrate the importance of treating PW for later disposal in the environment in order to mitigate ecotoxicological impacts. Further photoelectrocatalysis appeared to be a promising tool for treating PW samples prior to disposal and exposure of aquatic ecosystems.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Indústria de Petróleo e Gás , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Aliivibrio fischeri/efeitos dos fármacos , Animais , Daphnia/efeitos dos fármacos , Oxigênio/química , Petróleo/toxicidade , Testes de Toxicidade Aguda
2.
Toxicol In Vitro ; 71: 105069, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33309870

RESUMO

Three-dimensional skin models, also named 3D skin models, human skin equivalents (HSEs), or Human Epidermal Equivalents (HEEs), have been increasingly used for chemical assessments in terms of efficacy and safety. Considering this, we developed an HEE model using immortalized HaCaT cells, aiming to overcome the limitation of primary tissue source. Our 3D model (HaCaT-HEE) exhibited important markers of cell differentiation (CK10, CK14, involucrin, and filaggrin), although the stratum corneum was shown to be modest. Besides, the model showed a good prediction potential considering membrane permeability, sensitivity, specificity, and accuracy in distinguishing irritant and corrosive effects after exposure to selected chemicals recommended by the OECD protocols. We also validated the formazan determination for the MTT method using High-Performance Liquid Chromatography (HPLC). For that, we considered carry over, linearity, reproducibility/robustness, accuracy, precision, selectivity, and matrix effect, according to the Food and Drug Administration (FDA) guideline. Based on our results, we can conclude that our model has an acceptable predictive value for the safety evaluation of compounds after skin exposure, with the great advantage of being constructed using immortalized cells.


Assuntos
Cáusticos/toxicidade , Irritantes/toxicidade , Queratinócitos/efeitos dos fármacos , Testes de Irritação da Pele/métodos , Alternativas aos Testes com Animais , Linhagem Celular , Permeabilidade da Membrana Celular/efeitos dos fármacos , Epiderme , Proteínas Filagrinas , Humanos
3.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);65(1): 112-118, fev. 2013. tab
Artigo em Português | LILACS | ID: lil-667544

RESUMO

Foi avaliado se o espaço de alojamento influencia o desenvolvimento da mucosa do intestino delgado de frangos, sendo usado um esquema fatorial 4 x 2 (14, 28, 42, 55 dias de idade e alojamento pequeno: 0,11m²/ave e grande: 0,525m²/ave). Foram analisadas: altura, perímetro e número dos vilos, profundidade das criptas, número de células caliciformes e número de vilos sem e com perda de epitélio e exposição do conjuntivo. Em ambos os espaços de alojamento, o número de vilos diminuiu e a profundidade das criptas aumentou com a idade nas três regiões intestinais. A altura e o perímetro dos vilos aumentaram de 14 para 28 dias no jejuno e íleo, e o número de células caliciformes foi maior no duodeno e íleo a partir dos 42 dias. A perda de epitélio pelos vilos do íleo aumentou com a idade. Nas aves do alojamento grande, ocorreu aumento na altura e no perímetro dos vilos duodenais com a idade, possibilitado pelo aumento na profundidade das criptas, que resultou em vilos maiores nessas aves do que nas do alojamento pequeno aos 55 dias de idade. O número de células caliciformes diminuiu nas aves do alojamento pequeno aos 42 dias de idade. Os dados mostram que o tamanho do alojamento interferiu no modelo de desenvolvimento temporal da mucosa intestinal e que frangos apresentaram maior tamanho de vilo duodenal quando alojados em espaço maior.


This study evaluated if enclosure size and age influence the intestinal mucosa development of broiler chickens, using an experimental design in an 4x2 factorial arrangement (14, 18, 42 and 55 days of age and two enclosure spaces: small= 0.11m² /bird and large= 0.525m²/bird). Villous height, perimeter and number, and crypt depth, goblet cells number, and number of villous without and with epithelium loss and conjunctive tissue exposition were analyzed in duodenum, jejunum and ileum. Regardless of enclosure size, the villous number diminished and the crypt depth increased with the age in the three intestinal regions. From 14 to 28 days of age, villous height and perimeter increased in the jejunum and ileum. The number of goblet cells was greater from 42 days in duodenum and ileum, and epithelium loss increased until 42 days in the ileum. Broilers housed in small and large enclosures differed in the intestinal characteristics from 42 days. In broilers housed in large enclosure, duodenal villous height and perimeter increased with the age, with an increase in the crypt depth, reaching greater size at 55 days of age than duodenal villous of the broilers housed in a small enclosure. These later presented at 42 days a smaller number of goblet cells than the former. According these results, enclosure size influenced the temporal pattern of the intestinal mucosa development, and broilers presented major duodenal villous growth when housed in large enclosures.


Assuntos
Animais , Galinhas , Células Caliciformes , Mucosa Intestinal/patologia , Mucosa Intestinal , Epitélio
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