| |
|
|
|
Registro Completo |
|
Biblioteca(s): |
Embrapa Meio Ambiente. |
|
Data corrente: |
05/04/2017 |
|
Data da última atualização: |
10/07/2017 |
|
Tipo da produção científica: |
Resumo em Anais de Congresso |
|
Autoria: |
CLEMENTE, Z.; CASTRO, V. L. S. S. de; MARTINEZ, D. S. |
|
Afiliação: |
Z. CLEMENTE; VERA LUCIA SCHERHOLZ S DE CASTRO, CNPMA; D. S. MARTINEZ. |
|
Título: |
Influence of surface characteristics on graphene oxide toxicity for zebrafish embryo. |
|
Ano de publicação: |
2016 |
|
Fonte/Imprenta: |
In: SETAC EUROPE ANNUAL MEETING, 26., 2016, Nantes. Proceedings... Brussels: SETAC, 2016. Ref. TU044. |
|
Páginas: |
p. 203. |
|
Idioma: |
Inglês |
|
Conteúdo: |
Despite nanotoxicological studies have been intensified in recent years, gaps remain in the methods used to assess the nanotechnology risks. These gaps are due to the complex nanomaterials behavior in the environment, especially in the presence of organic matter and depending on the nanomaterial characteristics. Studies indicate that humic acid present in the aquatic environment can increase the stability of nanomaterial dispersions and may change its toxicity to aquatic organisms. The adsorption of oxidative debris (carboxylated carbonaceous fragments - CCFs) has also been discussed as an important factor influencing GO properties and behavior. The surface characteristics of GO can influence its biotechnological application as well as its toxicological effects. The aim of this study was to evaluate the influence of the presence of oxidative debris and humic acid in the toxicity of graphene oxide (GO) utilizing Fish Embryo Toxicity Test (FET test). GO (Sigma Aldrich) was refluxed with NaOH (0.01M, 1h, 90oC) and HCl (0.1M, 1h, 90oC) to produce GO without debris (GOwd). GO And GOwd were characterized through spectrophotometry, dynamic light scattering and atomic force microscopy. Zebrafish embryos (Danio rerio) were exposed during 96 h to 100 mg.L-1 GO or GOwd, in presence or absence of humic acid (HA, 20 mg.L-1). A control group exposed to reconstituted water was also performed. At the end of the exposure period, the larvae were measured and frozen at -20oC for subsequent evaluation of acetylcholinesterase activity (AchE). We also performed an in vitro test to evaluate direct effect of the nanomaterial in zebrafish AchE activity. Homogenates of zebrafish larvae were incubated with GO and GOwd at 30 mg/L (20 min, 30oC) before AchE assay was performed. Both GO agglomerated and precipitated quickly in reconstituted water. The presence of HA in the medium stabilized the GO suspensions similarly to that occurred with GO in ultrapure water. There was no difference between groups related to the occurrence of embryo malformation or mortality. Larvae exposed to GO were shorter and showed lower AchE activity than control and group exposed to GOwd. The in vitro test showed that the nanomaterial did not inhibit AchE activity. The nanomaterial showed low toxicity to embryo, but the reduction in total length and AchE activity in the organisms can be due to indirect effects in zebrafish development. More experiments will be performed to understand those effects. MenosDespite nanotoxicological studies have been intensified in recent years, gaps remain in the methods used to assess the nanotechnology risks. These gaps are due to the complex nanomaterials behavior in the environment, especially in the presence of organic matter and depending on the nanomaterial characteristics. Studies indicate that humic acid present in the aquatic environment can increase the stability of nanomaterial dispersions and may change its toxicity to aquatic organisms. The adsorption of oxidative debris (carboxylated carbonaceous fragments - CCFs) has also been discussed as an important factor influencing GO properties and behavior. The surface characteristics of GO can influence its biotechnological application as well as its toxicological effects. The aim of this study was to evaluate the influence of the presence of oxidative debris and humic acid in the toxicity of graphene oxide (GO) utilizing Fish Embryo Toxicity Test (FET test). GO (Sigma Aldrich) was refluxed with NaOH (0.01M, 1h, 90oC) and HCl (0.1M, 1h, 90oC) to produce GO without debris (GOwd). GO And GOwd were characterized through spectrophotometry, dynamic light scattering and atomic force microscopy. Zebrafish embryos (Danio rerio) were exposed during 96 h to 100 mg.L-1 GO or GOwd, in presence or absence of humic acid (HA, 20 mg.L-1). A control group exposed to reconstituted water was also performed. At the end of the exposure period, the larvae were measured and frozen at -20oC for subsequent eva... Mostrar Tudo |
|
Palavras-Chave: |
Graphne; Zebrafish. |
|
Categoria do assunto: |
W Química e Física |
|
URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/161626/1/clemente-influence.pdf
|
|
Marc: |
LEADER 03052nam a2200169 a 4500
001 2068135
005 2017-07-10
008 2016 bl uuuu u00u1 u #d
100 1 $aCLEMENTE, Z.
245 $aInfluence of surface characteristics on graphene oxide toxicity for zebrafish embryo.$h[electronic resource]
260 $aIn: SETAC EUROPE ANNUAL MEETING, 26., 2016, Nantes. Proceedings... Brussels: SETAC, 2016. Ref. TU044.$c2016
300 $ap. 203.
520 $aDespite nanotoxicological studies have been intensified in recent years, gaps remain in the methods used to assess the nanotechnology risks. These gaps are due to the complex nanomaterials behavior in the environment, especially in the presence of organic matter and depending on the nanomaterial characteristics. Studies indicate that humic acid present in the aquatic environment can increase the stability of nanomaterial dispersions and may change its toxicity to aquatic organisms. The adsorption of oxidative debris (carboxylated carbonaceous fragments - CCFs) has also been discussed as an important factor influencing GO properties and behavior. The surface characteristics of GO can influence its biotechnological application as well as its toxicological effects. The aim of this study was to evaluate the influence of the presence of oxidative debris and humic acid in the toxicity of graphene oxide (GO) utilizing Fish Embryo Toxicity Test (FET test). GO (Sigma Aldrich) was refluxed with NaOH (0.01M, 1h, 90oC) and HCl (0.1M, 1h, 90oC) to produce GO without debris (GOwd). GO And GOwd were characterized through spectrophotometry, dynamic light scattering and atomic force microscopy. Zebrafish embryos (Danio rerio) were exposed during 96 h to 100 mg.L-1 GO or GOwd, in presence or absence of humic acid (HA, 20 mg.L-1). A control group exposed to reconstituted water was also performed. At the end of the exposure period, the larvae were measured and frozen at -20oC for subsequent evaluation of acetylcholinesterase activity (AchE). We also performed an in vitro test to evaluate direct effect of the nanomaterial in zebrafish AchE activity. Homogenates of zebrafish larvae were incubated with GO and GOwd at 30 mg/L (20 min, 30oC) before AchE assay was performed. Both GO agglomerated and precipitated quickly in reconstituted water. The presence of HA in the medium stabilized the GO suspensions similarly to that occurred with GO in ultrapure water. There was no difference between groups related to the occurrence of embryo malformation or mortality. Larvae exposed to GO were shorter and showed lower AchE activity than control and group exposed to GOwd. The in vitro test showed that the nanomaterial did not inhibit AchE activity. The nanomaterial showed low toxicity to embryo, but the reduction in total length and AchE activity in the organisms can be due to indirect effects in zebrafish development. More experiments will be performed to understand those effects.
653 $aGraphne
653 $aZebrafish
700 1 $aCASTRO, V. L. S. S. de
700 1 $aMARTINEZ, D. S.
Download
Esconder MarcMostrar Marc Completo |
|
Registro original: |
Embrapa Meio Ambiente (CNPMA) |
|
|
Biblioteca |
ID |
Origem |
Tipo/Formato |
Classificação |
Cutter |
Registro |
Volume |
Status |
URL |
Voltar
|
|
|
Registro Completo
|
Biblioteca(s): |
Embrapa Amazônia Oriental. |
|
Data corrente: |
08/06/2005 |
|
Data da última atualização: |
29/11/2016 |
|
Tipo da produção científica: |
Boletim de Pesquisa e Desenvolvimento |
|
Autoria: |
GONÇALVES, C. A.; RODRIGUES FILHO, J. A.; CAMARÃO, A. P.; DUTRA, S. |
|
Afiliação: |
CARLOS ALBERTO GONÇALVES, CPATU; JOSE ADERITO RODRIGUES FILHO, CPATU; ARI PINHEIRO CAMARÃO, CPATU; SATURNINO DUTRA, CPATU. |
|
Título: |
Manejo de vacas leiteiras no Nordeste paraense. |
|
Ano de publicação: |
2003 |
|
Fonte/Imprenta: |
Belém, PA: Embrapa Amazônia Oriental, 2003. |
|
Páginas: |
16 p. |
|
Série: |
(Embrapa Amazônia Oriental. Boletim de pesquisa e desenvolvimento, 22). |
|
Idioma: |
Português |
|
Conteúdo: |
VIsando avaliar o ofeito do manejo de vacas leiteiras com e sem método de secagem, na produção de leite, peso vivo pré e pós-parto, assim como a performance dos bezerros durante a fase do nascimento e a desmama, foi realizada uam pesquisa no Campo Experimental da Embrapa Amozônica Oriental. |
|
Palavras-Chave: |
Brasil; Manejo animal; Pará; Região Nordeste; Terra Alta. |
|
Thesagro: |
Ganho de Peso; Manejo; Produção Animal; Vaca Leiteira. |
|
Thesaurus NAL: |
Amazonia. |
|
Categoria do assunto: |
-- |
|
URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/34523/1/ORIENTAL-BPD22.pdf
|
|
Marc: |
LEADER 01080nam a2200289 a 4500
001 1406834
005 2016-11-29
008 2003 bl uuuu u0uu1 u #d
100 1 $aGONÇALVES, C. A.
245 $aManejo de vacas leiteiras no Nordeste paraense.
260 $aBelém, PA: Embrapa Amazônia Oriental$c2003
300 $a16 p.
490 $a(Embrapa Amazônia Oriental. Boletim de pesquisa e desenvolvimento, 22).
520 $aVIsando avaliar o ofeito do manejo de vacas leiteiras com e sem método de secagem, na produção de leite, peso vivo pré e pós-parto, assim como a performance dos bezerros durante a fase do nascimento e a desmama, foi realizada uam pesquisa no Campo Experimental da Embrapa Amozônica Oriental.
650 $aAmazonia
650 $aGanho de Peso
650 $aManejo
650 $aProdução Animal
650 $aVaca Leiteira
653 $aBrasil
653 $aManejo animal
653 $aPará
653 $aRegião Nordeste
653 $aTerra Alta
700 1 $aRODRIGUES FILHO, J. A.
700 1 $aCAMARÃO, A. P.
700 1 $aDUTRA, S.
Download
Esconder MarcMostrar Marc Completo |
|
Registro original: |
Embrapa Amazônia Oriental (CPATU) |
|
|
Biblioteca |
ID |
Origem |
Tipo/Formato |
Classificação |
Cutter |
Registro |
Volume |
Status |
Fechar
|
| Expressão de busca inválida. Verifique!!! |
|
|
