Data/hora: 05/06/2024 12:21:54

Provedor de dados: 	74	
País: 	Brazil	
Título: 	Genotoxicity of titanium dioxide nanoparticles and triggering of defense mechanisms in Allium cepa	
Autores: 	Santos Filho,Ronaldo dos; Vicari,Taynah; Santos,Samuel A.; Felisbino,Karoline; Mattoso,Ney; Sant’Anna-Santos,Bruno Francisco; Cestari,Marta Margarete; Leme,Daniela Morais.	
Data: 	2019-06-01	
Ano: 	2019	
Palavras-chave: 	Chromosomal aberrations; Micronuclei; Nucleolar alterations; Cellular alterations; Nanoparticle phase-change.	
Resumo: 	Abstract Titanium dioxide nanoparticles (TiO2NPs) are widely used and may impact the environment. Thus, this study used a high concentration of TiO2NP (1000 mg/L) to verify the defense mechanisms triggered by a plant system – an indicator of toxicity. Furthermore, this study aimed at completely characterizing TiO2NP suspensions to elucidate their toxic behavior. TiO2NPs were taken up by meristematic cells of Allium cepa, leading to slight inhibition of seed germination and root growth. However, severe cellular and DNA damages were observed in a concentration-dependent manner (10, 100, and 1000 mg/L). For this reason, we used the highest tested concentration (1000 mg/L) to verify if the plant cells developed defense mechanisms against the TiO2NPs and evaluated other evidences of TiO2NP genotoxicity. Nucleolar alterations and plant defense responses (i.e., increased lytic vacuoles, oil bodies and NP phase change) were observed in meristematic cells exposed to TiO2NP at 1000 mg/L. In summary, TiO2NPs can damage the genetic material of plants; however, plants displayed defense mechanisms against the deleterious effects of these NPs. In addition, A. cepa was found to be a suitable test system to evaluate the cyto- and genotoxicity of NPs.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572019000300425	
Editor: 	Sociedade Brasileira de Genética	
Relação: 	10.1590/1678-4685-gmb-2018-0205	
Formato: 	text/html	
Fonte: 	Genetics and Molecular Biology  v.42 n.2 2019	
Fonte: 	info:eu-repo/semantics/openAccess