The continuous search for biologically active compound candidates pushes the pursuit of new substances produced by diverse organisms. Endophytic fungi are known as a promising source of metabolites with several biological activities. Based on the rich Amazonian biodiversity and the chemical potential of microbial sources, three Talaromyces strains, all major endophytes from their respective host plants, were studied aiming at the isolation of biologically active secondary metabolites. Through classical chromatographic approaches, 13 compounds were isolated from the antimicrobial extracts of the studied strains. From these, polyketides, steroids, anhydrides, and phenolic compounds were identified. Among them, two previously undescribed compounds were elucidated based on spectroscopic and spectrometric methods, a homodimer chromanone and a maleic anhydride methyl ester. The antimicrobial activity against a panel of pathogenic microorganisms from extracts, fractions, and isolated compounds was evaluated.

RESUMO Objetivou-se, neste estudo, avaliar a produtividade de colmos de dez cultivares de cana-de-açúcar (RB962962, RB 931011, RB931530, RB98710, RB92579, RB867515, RB863129, SP791011, RB72454 e VAT90212) submetida aos regimes hídricos de deficiência, irrigação plena e excedente hídrico, por gotejamento subsuperficial, durante três ciclos de cultivo (2011-2014). O ensaio foi conduzido no Campo Experimental da Embrapa Meio-Norte, Teresina, PI, em Argissolo Vermelho-Amarelo Distrófico. As cultivares RB962962 (162,3 Mg ha-1) e RB867515 (158,5 Mg ha-1) apresentam melhor produtividade de colmos em comparação às demais cultivares, em todos os regimes hídricos e ciclos de cultivo.

ABSTRACT This study aimed to evaluate the stalk yield of ten sugarcane cultivars (RB962962, RB931011, RB931530, RB98710, RB92579, RB867515, RB863129, SP791011, RB72545 and VAT90212) subjected to water deficit, full irrigation and water surplus by subsurface drip irrigation, during three cropping seasons (2011-2014). The experiment was conducted at the Experimental Field of Embrapa Meio-Norte, Teresina, Piauí State, Brazil, in dystrophic Red Yellow Argisol. The cultivars RB962962 (162.3 Mg ha-1) and RB867515 (158.5 Mg ha-1) have better stalk yield compared with other cultivars in all water regimes and cropping seasons.

A contagem de plaquetas por microscopia é uma ferramenta fundamental na avaliação dos pacientes com doenças que acometem as plaquetas, na medida em que complementa e corrobora as informações fornecidas pelos analisadores hematológicos, além de servir de ferramenta de controle interno da qualidade das contagens automatizadas de plaquetas. O objetivo deste trabalho foi comparar quatro métodos manuais de estimativa microscópica da contagem de plaquetas, considerando a correlação com a contagem automatizada de plaquetas e a correlação entre um método e outro, além de fornecer subsídios para a validação dos mesmos nos laboratórios de hematologia. Foram avaliados, neste trabalho, o método de Fonio modificado, o de Bárbara H. O'Connor, o de Nosanchuk, Chang & Bennett e um método alternativo baseado em um cálculo envolvendo a hemoglobina do paciente. Todos obtiveram boa correlação estatística quando comparados com a contagem automatizada de plaquetas e entre um e outro, sugerindo que o seu uso pode ser recomendado na avaliação plaquetária de pacientes com os mais diversos valores de contagem de plaquetas.

The platelet blood smear is an important tool in the evaluation of platelet disorders because it adds useful information to data provided by hematology analyzers. Furthermore, it serves as a tool for the internal quality control of automated counts. The aim of this work was to compare four manual methods of estimating platelets and to correlate the results with automated platelet counts. This study may also assist in the validation of these methods. The methodologies evaluated in this work were the modified Fonio method, the Barbara H. O'Connor method, the Nosanchuk Chang & Bennett method and an alternative method based on the patient's hemoglobin. All methodologies had good correlation coefficients both when compared with the other methods tested and with automated platelet counts suggesting that their use can be recommended for the evaluation of the platelet status of any patient.

In potentiometric titrations of metal cations with EDTA the Hg/HgY2- system is usually used to detect the end point. However, the use of mercury has been discouraged in analytical procedures due to its toxicity. In this work the Cu/CuY2- system was used as indicator electrode for potentiometric titrations of some metal cations with EDTA. The solutions of Cu2+, Cd2+, Mn2+, Co2+ and Zn2+ were titrated with Na2EDTA solution in the presence of a small concentration of the CuY2- complex using a copper wire as indicator electrode. The potentiometric titrations with the Cu/CuY2- system showed good correlation when compared with an Hg/HgY2- system.

The hydrated sodium salt of EDTA, Na2H2Y·2H2O, cannot be used as a primary standard for titrations due to uncertainties in the water content. An alkalimetric titration of the homogenized solid in the presence of a small excess of BaCl2·2H2O allows one to titrate quantitatively the released two hydrogen cations with end-point indication by phenolphthalein or potentiometry. This leads one to calculate the average molar mass of the reagent and its water content, allowing to use it to prepare EDTA standard solutions. One titrated sample led to the formula Na2H2Y·1.876 H2O, and 370.01 g.mol-1 for the average molar mass.