Therapeutic Concentrations of Mitoxantrone Elicit Energetic Imbalance in H9c2 Cells as an Earlier Event

Mitoxantrone (MTX) is a chemotherapeutic agent that emerged as an alternative to anthracycline therapy. However, MTX also causes late cardiotoxicity, being oxidative stress and mitochondrial-impaired function proposed as possible mechanisms. This work aimed to investigate the relevance of these mechanisms to the MTX toxicity in H9c2 cells, using therapeutic concentrations. The observed cytotoxicity of MTX was time and concentration dependent in both lactate dehydrogenase leakage assay and MTT reduction assay. Two therapeutic concentrations (100 nM and 1 lM) and three time points were selected (24, 48, and 96 h) for further studies. Both MTX concentrations caused a significant increase in caspase-3 activity, which was not prevented by inhibiting MTX CYP450-metabolism. Significant decreases were observed in the total and reduced glutathione levels only in MTX 100 nM at 96 h; however, neither alterations in oxidized glutathione nor increases in the malondialdehyde levels were observed at any time or concentrations tested. On the other hand, changes in the intracellular ATP levels, mitochondrial membrane potential, and intracellular calcium levels were observed in both concentrations and all time tested. Noteworthy, decreased levels of ATP-synthase expression and activity and increases in the reactive species generation were observed at 96 h in both working concentrations. However, the radical scavenger N-acetylcysteine or the mitochondrial function enhancer L-carnitine did not prevent MTX cytotoxicity. Thus, this work evidenced the early MTX-induced energetic crisis as a possible key factor in the cell injury.This work received financial support from ‘‘Fundação para a Ciência e Tecnologia (FCT),’’ Portugal (EXPL/ DTP-FTO/0290/2012) and by ‘‘Fundo Comunitário Europeu’’ (FEDER) under the frame of ‘‘Eixo I do Programa Operacional Fatores de Competitividade (POFC) do QREN’’ (COMPETE: FCOMP- 01-0124-FEDER-027749). The work was also supported by FCT within the framework of Strategic Projects for Scientific Research Units of R&D (project PEst-C/EQB/LA0006/2011). LGR and VVB thank FCT for their PhD Grant (SFRH/BD/63473/2009 and SFRH/ BD/82556/2011, respectively) and VMC thank FCT for her Post-doc Grant (SFRH/BPD/63746/2009)

Qualidade do melão cantaloupe cv. Hy-Mark minimamente processado e armazenado sob refrigeração Quality of cantaloupe melon cv. Hy-Mark minimally processed and refrigerated

A maioria das pesquisas em melão minimamente processado é concentrada no tipo 'cantaloupe', devido à sua importância no mercado internacional. O objetivo deste trabalho foi avaliar a qualidade do melão cantaloupe cv. Hy-Mark minimamente processado. Os frutos foram lavados e sanitizados, sendo em seguida cortados na forma de cubos, imersos em solução de CaCl2, acondicionados em embalagens flexíveis PET (tereftalato de polietileno) e armazenados a 4ºC por 9 dias. O delineamento foi conduzido inteiramente casualizado, com três repetições. A intervalos de três dias, amostras foram coletadas e analisadas quanto a coliformes totais e fecais, e contagem de bactérias aeróbias mesófilas e bolores e leveduras, pH, sólidos solúveis totais, acidez, vitamina C, açúcares redutores totais, atividade de água, firmeza e análise sensorial através do atributo de aceitação global. O melão minimamente processado apresentou boa estabilidade física, físico-química, microbiológica e sensorial, estimando-se em 9 dias a vida útil deste produto a 4ºC.<br>Most of the research into minimally processed melon is focused on cantaloupe melon, due to its importance in the international market. The objective of this work was to evaluate the quality of cantaloupe melon cv. Hy-Mark, minimally processed and refrigerated. Fruits were washed, sanitized, cut and imbedded in a calcium chloride solution and packed in PET and stored at 4ºC during 9 days. At three-day intervals samples were collected and analyzed for total and fecal coliforms, counting of aerobic mesophilic bacterias, molds and yeast, SS (soluble solids), TTA (total titrable acidity), firmness, pH, TRS (total reducing sugar), Aw, vitamin C, color and acceptability. The minimally processed melon showed good overall physical, pyisico-chemical, microbiological and sensorial stability during the storage period

Collection and morphological characterization of sweet potato landraces in north of Rio de Janeiro state Coleta e caracterização morfológica de variedades locais de batata-doce no norte do Rio de Janeiro

The traditional farmers play an important role in plant genetic resources conservation. Collecting the germplasm maintained by these farmers is a very important action to avoid genetic variability losses. The goals of this work were to collect sweet potato from farms in the north of Rio de Janeiro state; to gather information regarding to the farmers profile, and to characterize the sweet potato landraces collected using morphological descriptors. Fifty three farms were visited in six collection expedition and 46 accessions were collected. During the visits the farmers were interviewed using a query with ten items. Six root traits and eight descriptors for vegetative parts were used for morphological characterization. The data were analyzed based on Cole-Rodgers distance and clustering was done with UPGMA method. Familiar agriculture with subsistence objective was observed and sweet potato was cultivated by 72% of the farmers at least for more than a decade, supporting the observation that this vegetable is traditionally cultivated in small areas in the specific region. The morphological characterization was efficient to detect genetic variability among accessions, revealing that traditional farmers from Campos dos Goytacazes and São João da Barra are responsible for sweet potato genotypes conservation with expressive genetic diversity in their properties. There was no relationship between genetic distance and collecting areas.<br>Os agricultores tradicionais têm um papel fundamental na conservação dos recursos genéticos vegetais e a coleta de germoplasma mantido por esses produtores é muito importante para evitar a perda da variabilidade genética. Os objetivos deste trabalho foram coletar germoplasma de batata-doce em propriedades rurais situadas no norte do estado do Rio de Janeiro; levantar informações quanto ao perfil dos produtores rurais visitados durante as coletas, e caracterizar morfologicamente as variedades locais de batata-doce coletadas. Em seis viagens de coleta foram visitadas 53 propriedades rurais, e coletados 46 acessos. Em todas as visitas foi possível entrevistar o produtor por meio de questionário contendo dez itens. Para a caracterização, foram usados seis caracteres de raiz e oito da parte aérea. A análise dos dados foi efetuada com o uso da distância de Cole-Rodgers e o agrupamento foi gerado com o método UPGMA. Foi constatado predomínio da agricultura familiar, voltada para subsistência, sendo que 72% dos agricultores cultivavam a batata-doce há mais de uma década, o que evidencia a tradição de cultivo desta hortaliça em pequenas áreas na região. A caracterização morfológica foi eficiente para detectar a variabilidade genética entre os acessos, demonstrando que os agricultores tradicionais dos municípios de Campos dos Goytacazes e São João da Barra detêm genótipos de batata-doce com expressiva diversidade genética em suas propriedades. Não foi detectada correlação entre a distância genética e os locais de coleta