15 results on '"Flores, Érico Marlon de Moraes"'
Search Results
2. On a single method for determining As and Hg in dietary supplements by CVG-MIP OES: optimization of the multimode sample introduction system.
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Bitencourt, Gustavo Rossato, Duarte, Fabio Andrei, Dressler, Valderi Luiz, Bolzan, Rodrigo Cordeiro, Flores, Érico Marlon de Moraes, and Mello, Paola Azevedo
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DIETARY supplements ,INDUCTIVELY coupled plasma atomic emission spectrometry ,DIGESTION - Abstract
A single method was developed for the determination of As and Hg in dietary supplements by chemical vapor generation coupled with microwave-induced plasma optical emission spectrometry (CVG-MIP OES) using a commercial multimode sample introduction system (MSIS). The MSIS setup, general CVG conditions, and pre-reduction methods for the conversion of As(V) to As(III) were evaluated. It was possible to reach a magnification factor of 7 and 2 times for As and Hg, respectively, using the optimized MSIS setup compared to the standard setup. The proposed method provided a limit of quantification (LOQ) in the range from 5 to 15 and 29 to 93 ng g
−1 for As and Hg, respectively, which complies with the maximum concentration of 1.5 μg g−1 for these elements in dietary supplements set by United States Pharmacopeia (USP) General Chapter 2232. This method was applied for the simultaneous determination of As and Hg in four classes of dietary supplements (vitamins and minerals, minerals, amino acids, and botanicals), which were previously digested by microwave-assisted wet digestion. The concentrations of both elements were found to be below the maximum limit established by USP General Chapter 2232 in all the samples. The accuracy of the proposed method was evaluated using certified reference materials (CRMs) and no statistical difference was observed between the reference and obtained values (t-test, confidence level of 95%). Also, no difference was observed in the results obtained using the proposed method with those using comparative methods (CVG-ICP-MS for Hg after wet digestion and ICP-MS for As after microwave-induced combustion (MIC)). After optimizing the MSIS setup and CVG conditions, the proposed method can be considered an alternative for the quality control of As and Hg in dietary supplements, given that it is suitable for the determination of these elements according to the limit established by USP. [ABSTRACT FROM AUTHOR]- Published
- 2023
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3. Application of Zn2SnO4 photocatalyst prepared by microwave-assisted hydrothermal route in the degradation of organic pollutant under sunlight
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Foletto, Edson Luiz, Simões, Jana Marimon, Mazutti, Marcio A., Jahn, Sérgio L., Muller, Edson Irineu, Pereira, Letícia Severo Fagundes, and Flores, Erico Marlon de Moraes
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- 2013
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4. Solid sampling coupled to flame furnace atomic absorption spectrometry for Mn and Ni determination in petroleum coke
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Bizzi, Cezar Augusto, Paniz, José Neri Gottfried, Rodrigues, Luiz Frederico, Dressler, Valderi Luiz, and Flores, Érico Marlon de Moraes
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- 2010
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5. Organic, inorganic and total mercury determination in fish by chemical vapor generation with collection on a gold gauze and electrothermal atomic absorption spectrometry
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Duarte, Fábio Andrei, Bizzi, Cezar Augusto, Antes, Fabiane Goldschmidt, Dressler, Valderi Luiz, and Flores, Érico Marlon de Moraes
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- 2009
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6. Evaluation of liquid chromatography inductively coupled plasma mass spectrometry for arsenic speciation in water from industrial treatment of shale
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Duarte, Fábio Andrei, Pereira, Juliana Severo Fagundes, Mesko, Márcia Foster, Goldschmidt, Fabiane, Flores, Érico Marlon de Moraes, and Dressler, Valderi Luiz
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- 2007
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7. Effect of antioxidant potential on severity of cirrhosis in humans
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Colpo, Elisângela, Farias, Julia Gomes, Farias, Iria Luiza Gomes, Brenner Reetz, Luiz Gustavo, Oliveira, Liliane, Carli, Diego Michelon de, Irineu Müller, Edson, Flores, Érico Marlon de Moraes, Roth Dalcin, Saulo, and Rocha, João Batista Teixeira da
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Selenium ,Selenio ,Hepatic cirrhosis ,Ascorbic acid ,Flow cytometry ,Ácido ascórbico ,Cirrosis hepática ,Citometría de flujo - Abstract
Background/Aims: to examine the relationship between the antioxidant potential and severity parameters of cirrhosis in humans. Methods: fifteen patients with hepatic cirrhosis (nine subjects - Child group B, and six subjects - Child group C) and nine control subjects were enrolled in the study. The main criteria taken into account to characterize the diagnosis of cirrhosis and its complications were the AST: ALT ratio, AST to platelet ratio index, Bonacini score, Meld score and Child classification. Those parameters were determined based on laboratory results and patient's clinical records. Se, Zn, ascorbic acid (AA) levels and oxidative stress parameters were measured in blood samples of cirrhotic patients. Results: the analysis of plasma levels of Se and AA showed low concentrations in cirrhotic patients compared with control subjects (P < 0.05). Though, there was a positive correlation between plasma of Se and severity parameters of cirrhosis in patients of Child group B and C. In the activity of the antioxidant enzymes only catalase was lower in patients of Child group C compared with control group. Conclusion: we found low plasma levels of Se and AA among cirrhotic patients. However, is not clear why selenium levels tend to increase with the severity of liver cirrhosis. Introducción/Objetivos: examinar la relación entre los potenciales antioxidantes y los parámetros de gravedad de la cirrosis en los seres humanos. Métodos: quince pacientes con cirrosis hepática (nueve sujetos - grupo Child B, y seis sujetos - grupo Child C) y nueve sujetos control fueron incluidos en el estudio. Los principales criterios que se tuvieron en cuenta para caracterizar el diagnóstico de la cirrosis y sus complicaciones fueron la AST: relación de ALT, AST índice de la relación de plaquetas, clasificación Bonacini, clasificación MELD y clasificación de Child. Estos parámetros fueron determinados con base en los resultados de laboratorio y los registros clínicos del paciente. Se midieron los niveles de Zn, ácido ascórbico (AA) y los parámetros de estrés oxidativo en muestras de sangre de pacientes cirróticos. Resultados: el análisis de los niveles plasmáticos de Se y AA mostraron bajas concentraciones en los pacientes cirróticos en comparación con los sujetos control (P < 0,05); sin embargo, hubo una correlación positiva entre el plasma de Se y los parámetros de gravedad de la cirrosis en pacientes del grupo Child B y C. En la actividad de las enzimas antioxidantes catalasa solamente fue menor en los pacientes del grupo Child C, en comparación con el grupo control. Conclusión: se encontraron niveles bajos en plasma de Se y AA en pacientes cirróticos. Sin embargo, no está claro por qué los niveles de selenio tienden a aumentar con la gravedad de la cirrosis hepática.
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- 2015
8. Titanium alloy miniscrews for orthodontic anchorage: an in vivo study of metal ion release = Miniimplantes de liga de titânio para ancoragem ortodôntica: um estudo in vivo de liberação de íon metálico
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Blaya, Micéli Beck Guimarães, Blaya, Diego Segatto, Mello, Paola de Azevedo, Flores, Érico Marlon de Moraes, and Hirakata, Luciana Mayumi
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lcsh:RK1-715 ,odontologia ,lcsh:Dentistry ,implantodontia ,ortodontia - Abstract
Objetivo: Examinar e comparar os níveis de diferentes íons metálicos liberados na saliva de pacientes com aparelhos ortodônticos, em diferentes tempos: antes e após a inserção de mini-implantes. Metodologia: A saliva de pacientes (n=20) foi coletada em quatro tempos diferentes: antes da inserção do mini-implante (T1), 10 minutos (T2), 7 dias (T3) e 30 dias após a remoção do mini-implante (T4). As amostras de saliva foram analisadas por espectrometria de massa de plasma com acoplamento por indução (ICP-MS) e espectrometria de emissão ótica por plasma acoplado indutivamente (ICP-OES). A liberação de nove diferentes ions metálicos foi observado: titânio (Ti), zinco (Zn), cromo (Cr), níquel (Ni), ferro (Fe), cobre (Cu), alumínio (Al), vanádio(V) e cobalto (Co). Os dados foram analisados por estatística descritiva. As concentrações de íons metálicos na saliva dos diferentes tempos estudados foram comparados através do teste pareado de Wilcoxon (α=5%). Resultados: No tempo T4, houve um aumento quantitativo na concentração salivar de Cu, Ti, V, Zn, assim como um decréscimo quantitativo na concentração salivar de Al, Co, Cr, Fe, Ni, quando comparados com T1. Conclusão: Pode ser concluído que a colocação de aparelho fixo ortodôntico associado com mini-implantes não leva a um aumento significativo na concentração salivar de íons metálicos
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- 2011
9. Journal of the Brazilian Chemical Society
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Korn, Maria das Graças Andrade, Bispo, Márcia Sousa, Korn, Mauro, Costa, Adilson Ben da, Mattos, Julio Cezar Paz de, Paniz, José Neri Gottfried, and Flores, Érico Marlon de Moraes
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Pre-concentration ,Direct solid analysis ,lead ,Flame atomic absorption spectrometry ,Naphthalene - Abstract
p. 1241-1247. Submitted by JURANDI DE SOUZA SILVA (jssufba@hotmail.com) on 2012-01-09T15:46:06Z No. of bitstreams: 1 27072.pdf: 158362 bytes, checksum: e32297e9dab37b2b093db6be09f3753b (MD5) Made available in DSpace on 2012-01-09T15:46:06Z (GMT). No. of bitstreams: 1 27072.pdf: 158362 bytes, checksum: e32297e9dab37b2b093db6be09f3753b (MD5) Previous issue date: 2005 Um dispositivo para a amostragem direta de sólidos por espectrometria de absorção atômica com chama (DSA-FAAS) é proposto para a determinação de chumbo em água, após o procedimento de extração em fase sólida. Uma solução tampão, NH4Cl-NH3, pH 8,1, e a fase sólida (vermelho de alizarina adsorvido em naftaleno) foram adicionados a amostra de água para adsorção de chumbo. Posteriormente, as amostras (até 200 mL) foram filtradas e a matriz de naftaleno foi seca, moída, até as partículas atingirem tamanho inferior a 80 µm e então mantida em dessecador até a determinação de Pb por DSA-FAAS. Amostras sólidas (de 0,1 a 2 mg) foram pesadas em recipientes de polietileno, os quais foram conectados ao dispositivo para introdução direta de sólidos na chama do tipo ar + acetileno. As amostras sólidas foram transportadas na forma de um aerossol seco até uma cela de quartzo em forma de "T" que foi acoplada ao queimador e posicionada entre este e o feixe óptico do espectrômetro de absorção atômica. Na chama, o vapor atômico gerado produziu um sinal transiente que era totalmente integrado em 2 s. O efeito das condições operacionais sobre o sinal analítico foi avaliado. Sinais de fundo foram sempre baixos (l = 217,0 nm) e não foram observados efeitos de memória. A massa característica foi de 1,1 ng de Pb. a calibração foi feita empregando-se diferentes massas de naftaleno impregnado com vermelho de alizarina, tratadas com soluções de referência de Pb. Os resultados foram considerados satisfatórios para concentrações de 30 e 50 µg L-1, tanto com respeito à exatidão (recuperações de 94 a 103%) como à precisão (desvio padrão relativo inferior a 5%, n=6). A estabilidade de Pb na fase sólida (naftaleno + vermelho de alizarina) foi avaliada até 45 dias e os resultados mostraram que o material sólido, após adsorção de Pb e secagem) pode ser armazenado durante este período. O dispositivo proposto, usado para a introdução de amostras sólidas no atomizador, pode ser acoplado facilmente a equipamentos convencionais para espectrometria de absorção atômica. São Paulo
- Published
- 2005
10. Determination of total arsenic by batch hydride generation atomic absorption spectrometry in injectable drugs containing high levels of Sb(V) as N-methylglucamine antimonate
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Flores, Érico Marlon de Moraes, Barcelos da Silva, Fabiana E., Santos, Eliane Pereira dos, Paula, Fávero Reisdorfer, Barin, Juliano Smanioto, Zanella, Renato, Dressler, Valderi Luiz, and Bittencourt, Celso Figueiredo
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HYDRIDES , *ARSENIC - Abstract
A procedure for the determination of arsenic by batch hydride generation atomic absorption spectrometry (HG AAS) in commercial samples of injectable drugs, containing high concentrations of Sb(V), is described. The procedure is based on the complexing effect for Sb of citric, oxalic and acetic acids as reaction media. Aqua regia was used for sample digestion prior to As determination by HG AAS. The following experimental conditions for the determination of total As, as As(V), were evaluated: the acid medium and its concentration, sodium tetrahydroborate concentration, purge time, and influence of the different oxidation states of As. The effect of the delay time after mixing of sample and acid solution was also studied. Optimized conditions were: 10% (m/v) citric acid, 1.5% (m/v) sodium tetrahydroborate solution and 30 s for purge time. A delay time of 1 h was required after the digested sample had been mixed with citric acid, before As determination could be carried out. No interference on As(III) and As(V) signals was observed in the presence of up to 1 mg Sb(V). The tolerance limits for Ni(II), Cu(II) and Pb(II) were 1 mg, 100 μg and 100 μg, respectively. Recovery tests for As(III) and As(V) resulted in values between 97 and 101%. Characteristic mass and detection limit (3σ), using the recommended conditions, were 0.52 and 0.8 ng, respectively, for total As. [Copyright &y& Elsevier]
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- 2002
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11. Development and characterization of microcapsules containing Bifidobacterium Bb-12 produced by complex coacervation followed by freeze drying.
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Marques da Silva, Thaiane, Jacob Lopes, Eduardo, Codevilla, Cristiane Franco, Cichoski, Alexandre José, Flores, Érico Marlon de Moraes, Motta, Mariana Heldt, da Silva, Cristiane de Bona, Grosso, Carlos Raimundo Ferreira, and de Menezes, Cristiano Ragagnin
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MOLECULAR capsules , *BIFIDOBACTERIUM , *COACERVATION , *FREEZE-drying , *MICROENCAPSULATION - Abstract
Microcapsules containing B. lactis were produced by complex coacervation in gelatin and gum Arabic followed by freeze drying and characterized by optical microscopy and scanning electron microscopy, as well as the resistance of probiotics to the in-vitro release in the simulated gastrointestinal tract and storage under different temperature conditions. Therefore, it formed microcapsules with high encapsulation efficiency (86.04% and 99.52%) and size between 100.12 and 203.32 μm. In addition, microencapsulated probiotics, both in wet and dry forms, maintained viability against the simulated gastrointestinal conditions. Finally, complex coacervation method was also efficient in maintaining the viability of probiotics during storage at temperatures of −18 °C for 120 days, 7 °C for 120 days and 25 °C for 90 days. Thus, our results demonstrated that complex coacervation method is an appropriate alternative to increase the viability of probiotics. [ABSTRACT FROM AUTHOR]
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- 2018
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12. Inulin, hi-maize, and trehalose as thermal protectants for increasing viability of Lactobacillus acidophilus encapsulated by spray drying.
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Nunes, Graciele Lorenzoni, Etchepare, Mariana De Araújo, Cichoski, Alexandre José, Zepka, Leila Queiroz, Jacob Lopes, Eduardo, Barin, Juliano Smanioto, Flores, Érico Marlon De Moraes, Da Silva, Cristiane De Bona, and De Menezes, Cristiano Ragagnin
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INULIN , *TREHALOSE , *LACTOBACILLUS acidophilus , *SPRAY drying , *SCANNING electron microscopy , *PHYSIOLOGY - Abstract
Microparticles containing inulin, hi-maize, and trehalose were produced through spray drying to encapsulate Lactobacillus acidophilus La-5. Afterwards, the encapsulation efficiency, thermal resistance, gastrointestinal simulation, storage stability, and the microparticles’ size and morphology were analyzed to evaluate the protective effect against the thermal conditions of the spray dryer of the different encapsulating matrices. Inulin and hi-maize encapsulating matrices showed the greatest encapsulation efficiency of 93.12% and 94.26%, respectively. Concerning thermal resistance, the trehalose encapsulating matrix provided the greatest protection for this microorganism. The microparticles produced with hi-maize showed the greatest viability in simulated gastrointestinal conditions thus providing higher protection for Lactobacillus acidophilus La-5. Regarding storage stability, microparticles containing trehalose showed the fewest viability losses during 120 days of storage. However, notably, at the end of 120 days of storage at room temperature (25 °C), microparticles containing inulin, hi-maize, and trehalose all kept their counts above the recommended level (>6 log CFU/g −1 ). Concerning the physical characteristics of the microparticles, particle sizes were as expected for products obtained by spray drying. Scanning electron microscopy showed no ruptures or cracks on the surfaces of the microparticles, a desirable characteristic for high protection. [ABSTRACT FROM AUTHOR]
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- 2018
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13. Desenvolvimento de métodos para análise isotópica de Mg, Sr e Pb de petróleo por MC-ICP-MS
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Henn, Alessandra Schneider, Flores, Érico Marlon de Moraes, Mello, Paola Azevedo, Mesko, Márcia Foster, Vanhaecke, Frank, Mester, Zoltan, Müller, Edson Irineu, and Bizzi, Cezar Augusto
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Petróleo ,Lead determination ,Magnesium determination ,Determinação de chumbo ,Strontium determination ,CIENCIAS EXATAS E DA TERRA::QUIMICA [CNPQ] ,Determinação de estrôncio ,Isotopic analysis ,Análise isotópica ,MC-ICP-MS ,Crude oil ,Determinação de magnésio - Abstract
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES Neste trabalho, foi feita a determinação das razões isotópicas de Mg, Sr e Pb em petróleo por espectrometria de massa com plasma indutivamente acoplado e multi-coletor (MC-ICP-MS). Dois métodos de preparo de amostra foram avaliados: (i) digestão por via úmida assistida por micro-ondas com cavidade de digestão pressurizada (MAWD-PDC) e (ii) solubilização de sólidos inorgânicos após a norma ASTM D4807. Usando a MAWD-PDC, até 0,5 g de petróleo foram eficientemente digeridos usando apenas 6 mL de HNO3 14,4 mol L-1 (75 min, temperatura de até 250 ° C). A MAWD-PDC mostrou ser um método de preparo de amostras adequado para a subsequente determinação da concentração e das razões isotópicas de Mg, Sr e Pb. Por outro lado, o método baseado na ASTM não requer nenhum equipamento sofisticado ou o uso de solventes halogenados. Com este método, até 10 g de petróleo podem ser dissolvidos em tolueno e filtrados através de uma membrana de nylon. Elementos presentes na forma de sólidos inorgânicos, como Mg e Sr, são retidos nessa membrana e podem ser facilmente recuperados em água. No entanto, Pb não foi recuperado usando esse método, possivelmente porque ele está presente no petróleo na forma de complexos orgânicos que não ficam retidos na membrana. Quatro procedimentos de isolamento usando cromatografia em coluna foram avaliados para o isolamento de Mg, Sr e Pb da matriz do petróleo. Para o Mg, o isolamento foi realizado usando a resina de troca catiônica AG 50W-X8. O isolamento de Sr e Pb foi feito utilizando um protocolo de isolamento sequencial com base no uso da resina Sr-spec. Ambos os protocolos de isolamento foram caracterizados por rendimentos quantitativos e remoção de elementos da matriz. Não foi observada diferença estatística significativa entre os resultados para as razões isotópicas de Mg e Sr obtidos usando ambos os métodos de preparo de amostra (MAWD-PDC e solubilização). Assim, os dois métodos de preparo de amostra podem ser usados para análise isotópica de Mg e Sr em petróleo. A composição isotópica Mg-Sr-Pb dos petróleos brasileiros avaliados neste trabalho está dentro da faixa observada para a água do mar e o leito rochoso do depósito. Os métodos desenvolvidos neste trabalho podem ser considerados ferramentas promissoras para decifrar a história de formação de reservatórios de petróleo. In this work, the determination of isotope ratios of Mg, Sr and Pb in crude oil by multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS) was performed. Two sample preparation methods were evaluated: (i) microwave-assisted wet digestion with a pressurized digestion cavity (MAWD-PDC); and (ii) solubilization of inorganic solids after the ASTM D4807 test method. Using MAWD-PDC, up to 0.5 g of crude oil was efficiently digested using just 6 mL of 14.4 mol L-1 HNO3 (75 min, temperature up to 250 °C). MAWD-PDC was shown to be a suitable sample preparation method for subsequent determination of Mg, Sr and Pb concentration and their isotope ratios. On the other hand, the ASTM based method does not require any sophisticated equipment or the use of halogenated solvents. With this method up to 10 g of oil can be dissolved in toluene and filtered through a nylon membrane. Elements present as inorganic solids, such as Mg and Sr, are retained on the nylon membrane and can be easily recovered in water. However, Pb was not recovered using this method, possibly because this analyte is present in crude oil as organic complexes that are not retained on the membrane. Four isolation protocols using column chromatography were evaluated for Mg, Sr and Pb isolation from crude oil matrix. For Mg, isolation was successfully carried out using the cation exchange resin AG 50W-X8. The isolation of Sr and Pb was performed using a sequential isolation protocol relying on the use of the Sr-spec resin. Both isolation protocols were characterized by quantitative yields and matrix elements removal. No statistical difference was observed between the results for Mg and Sr isotope ratios obtained using both sample preparation methods (MAWD-PDC and solubilization). Thus, both sample preparation methods can be used for Mg and Sr isotopic analysis of crude oil. The Mg-Sr-Pb isotopic composition of the Brazilian crude oils evaluated in this work was within the range observed for seawater and the deposit bedrock. The methods developed in this work can be considered as promising tools to decipher the formation history of oil reservoirs.
- Published
- 2021
14. Chromium determination in pharmaceutical grade barium sulfate by solid sampling electrothermal atomic absorption spectrometry with Zeeman-effect background correction
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Bolzan, Rodrigo Cordeiro, Rodrigues, Luis Frederico, Mattos, Júlio Cezar Paz de, Dressler, Valderi Luiz, and Flores, Érico Marlon de Moraes
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CHROMIUM group , *ABSORPTION , *CHROMIUM , *SIZE reduction of materials - Abstract
Abstract: A procedure for chromium (Cr) determination in pharmaceutical grade barium sulfate by direct solid sampling electrothermal atomic absorption spectrometry (DSS-ET AAS) with Zeeman-effect background correction was developed. Operational conditions for the proposed procedure and the use of citric acid, ammonium phosphate, palladium and magnesium nitrate as chemical modifiers were evaluated. Pyrolysis and atomization temperatures were set at 1500 and 2400°C, respectively and the use of matrix modifiers did not improve these conditions. Graphite platform presented high degradation rate, but minima changes were observed in the sensitivity or signal profile. Samples (0.3–1mg) were weighted and introduced into the furnace using a manual solid sampling system. The linear concentration range of the calibration curve was from 100 to 1800pg (R 2 >0.995). The characteristic mass was 7.7pg and the limit of detection was 2.4pg. Chromium concentration in commercial samples ranged from 0.45 to 1.06μgg−1 and these results were confirmed by standard addition method. The mean reproducibility was 12% (n =20 in a 3-day period) and repeatability was less than 9%. Results obtained using inductively coupled plasma optical emission spectrometry and conventional electrothermal atomic absorption spectrometry after extraction with HNO3 were around 20% lower than those obtained by the proposed procedure. It was assumed that the low results were due to incomplete extraction even using hard conditions related to temperature and pressure. The proposed procedure by DSS-ET AAS provided some advantages related to recommended pharmacopoeias methodology, as lower risks of contamination and analyte losses, higher specificity, accuracy and sensitivity, no toxic or unstable reagents are required, and calibration with aqueous standards was feasible. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
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15. Drosophila melanogaster - an embryonic model for studying behavioral and biochemical effects of manganese exposure.
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Ternes AP, Zemolin AP, da Cruz LC, da Silva GF, Saidelles AP, de Paula MT, Wagner C, Golombieski RM, Flores ÉM, Picoloto RS, Pereira AB, Franco JL, and Posser T
- Abstract
Embryonic animals are especially susceptible to metal exposure. Manganese (Mn) is an essential element, but in excess it can induce toxicity. In this study we used Drosophila melanogaster as an embryonic model to investigate biochemical and behavioral alterations due to Mn exposure. Flies were treated with standard medium supplemented with MnCl2 at 0.1 mM, 0.5 mM or 1 mM from the egg to the adult stage. At 0.5 mM and 1 mM Mn, newly ecloded flies showed significantly enhanced locomotor activity when assessed by negative geotaxis behavior. In addition, a significant increase in Mn levels (p < 0.0001) was observed, while Ca, Fe, Cu, Zn and S levels were significantly decreased. A significant drop in cell viability occurred in flies exposed to 1 mM Mn. There was also an induction of reactive oxygen species at 0.5 mM and 1 mM Mn (p < 0.05). At 1 mM, Mn increased Catalase (p < 0.005), Superoxide Dismutase (p < 0.005) and Hsp83 (p < 0.0001) mRNA expression, without altering Catalase or Superoxide Dismutase activity; the activity of Thioredoxin reductase and Glutatione-S-transferase enzymes was increased. Mn treatment did not alter ERK or JNK1/2 phosphorylation, but at 1 mM caused an inhibition of p38(MAPK) phosphorylation. Together these data suggest mechanisms of adaptation in the fly response to Mn exposure in embryonic life.
- Published
- 2014
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