Penetración Dentinaria in vitro del Hipoclorito de Sodio a Diferentes Concentraciones con las Técnicas de Irrigación Convencional y Ultrasónica Pasiva / In vitro Dentinary Penetration of Sodium Hypochlorite at Different Concentrations with the Conventional and Ultrasonic Passive Irrigation Techniques

RESUMEN: El objetivo del presente trabajo fue comparar la penetración dentinaria in vitro entre las concentraciones de hipoclorito de sodio (NaClO) al 5 % y al 2,5 % con técnicas de irrigación convencional e irrigación ultrasónica pasiva. Este fue un estudio transversal, prospectivo y experimental. Se trabajó con 40 segmentos radiculares (especímenes) de 5 mm de longitud, divididos en 4 grupos. Todos los especímenes se sumergieron en violeta cristal durante 24 horas. Se realizó la preparación biomecánica con sistema rotatorio Pro Taper. Al primer grupo se irrigó con NaClO al 2,5 % con irrigación convencional, al segundo grupo con NaClO al 2,5 % con irrigación convencional más irrigación ultrasónica pasiva por 30 segundos, al tercer grupo con NaClO al 5 % con irrigación convencional y al cuarto grupo con NaClO al 5 % con irrigación convencional más irrigación ultrasónica pasiva por 30 segundos. Al final de la preparación a todos los especímenes se les realizó un corte mesio distal. La profundidad de la penetración del NaClO fue deterrminado por el blanqueamiento de la mancha y medido con un microscopio de luz con una magnificación de 40 X. La prueba estadística usada fue ANOVA con un nivel de significancia de 5 %. El NaClO al 5 % con técnica de irrigación ultrasónica pasiva presentó la mayor penetración dentinaria in vitro.

ABSTRACT: The objective of the present study was to compare in vitro dentin penetration between 5 % and 2.5 % sodium hypochlorite (NaClO) concentrations using conventional irrigation and passive ultrasonic irrigation techniques. This was a cross-sectional, prospective and experimental study. It was worked with 40 root segments (specimen) of 5 mm length, divided into 4 groups. All specimens were immersed in crystal violet for 24 hours. The biomechanical preparation was performed with Pro Taper rotary system. The first group was irrigated with 2.5 % NaClO with conventional irrigation, the second group with 2.5 % NaClO with conventional irrigation plus ulrasonic passive irrigation for 30 seconds, the third group with 5 % NaClO with conventional irrigation and the fourth with 5 % NaClO with conventional irrigation plus ultrasonic passive irrigation for 30 seconds. At the end of the preparation, all specimens had a distal mesio cut. The depth of NaClO penetration was determined by bleaching of the stain and measured with a light microscope at a magnification of 40 X. The statistical test used was ANOVA with a significance level of 5 %. The 5 % NaClO with passive ultrasonic irrigation showed the highest dentin penetration in vitro.

Validation of an HPLC-UV method for the identification and quantification of bioactive amines in chicken meat / Validação de metodologia por HPLC/UV para identificação e quantificação de aminas bioativas em carne de frango de corte

A high-performance liquid chromatography with ultraviolet detection (HPLC-UV) method was validated for the study of bioactive amines in chicken meat. A gradient elution system with an ultraviolet detector was used after extraction with trichloroacetic acid and pre-column derivatization with dansyl chloride. Putrescine, cadaverine, histamine, tyramine, spermidine, and spermine standards were used for the evaluation of the following performance parameters: selectivity, linearity, precision, recovery, limits of detection, limits of quantification and ruggedness. The results indicated excellent selectivity, separation of all amines, a coefficient of determination greater than 0.99 and recovery from 92.25 to 102.25% at the concentration of 47.2mg.kg-1, with a limit of detection at 0.3mg.kg-1 and a limit of quantification at 0.9mg.kg-1 for all amines, with the exception of histamine, which exhibited the limit of quantification, of 1mg.kg-1. In conclusion, the performance parameters demonstrated adequacy of the method for the detection and quantification of bioactive amines in chicken meat.(AU)

Um método de cromatografia líquida de alta eficiência (CLAE) para pesquisa de aminas bioativas em carne de frango foi validado. Foi utilizado um sistema de gradiente de eluição com detector ultravioleta, após extração com ácido tricloroacético e derivação pré-coluna com cloreto de dansila. Os padrões de putrescina, cadaverina, histamina, tiramina, espermidina e espermina foram utilizados para avaliação dos seguintes parâmetros de desempenho: seletividade, linearidade, precisão, recuperação, limites de detecção, limites de quantificação e robustez. Os resultados mostraram excelente seletividade e separação de todas as aminas, coeficiente de determinação superior a 0,99, recuperação entre 92,25 e 105,25% na concentração 47,2mg.kg-1, limites de detecção de 0,3mg.kg-1 e limite de quantificação de 0,9mg.kg-1 para todas as aminas, com exceção da histamina, que apresentou o limite de quantificação mais alto, de 1mg.kg-1. Foi concluído que os parâmetros de desempenho demonstraram adequação do método para detecção e quantificação de aminas bioativas em carne de frango.(AU)

Development and validation of a new and economical stability indicating RP-HPLC method for cefixime trihydrate

ABSTRACT The present work describes the development of a new high performance liquid chromatographic (HPLC) method for the determination of Cefixime trihydrate under different stress conditons as specified by ICH. For the analysis, a Phenomenex (250 x 4.6 mm, 5 µm particle size) ODS column and a SPD 20 A UV detector at 289 nm was used. The selected mobile phase was 10 mM disodium hydrogen phosphate (with 0.5% TEA, pH adjusted to 6.3 with OPA) and methanol in the ratio of 75:25 (v/v) in isocratic mode at a flow rate of 1 mL.min-1.The linear regression analysis data for the calibration plots showed good linear relationship with r2 = 0.9997 in the concentration range of 5-100 μg.mL-1. The stress degradation was performed using acid, alkali, water, hydrogen peroxide and uv light.

RESUMO O presente trabalho descreve o desenvolvimento de um novo alta performance cromatografia líquida (HPLC) método para a determinação de cefixima tri-estresse sob diferentes condições, conforme especificado pelo ICH. Para a análise, a Phenomenex (250 x 4,6 mm, 5 µm de granulometria) ODS coluna e a SPD 20 um detector de UV em 289 nm foi utilizado. A fase móvel selecionado foi de 10 mM hidrogenofosfato dissódico (com 0,5% TEA, o pH ajustado para 6,3 com OPA) e de metanol em razão de 75:25 (v/v) no modo isocrático com uma taxa de fluxo de 1 mL.min-1. A análise de regressão linear para dados da calibração parcelas apresentaram boa relação linear com r2 = 0,9997 no intervalo de concentração de cerca de 5 100 µg.mL-1. Degradação do estresse foi realizado utilizando um ácido, alcalino, a água, o peróxido de hidrogênio e luz uv.

Determinación cuantitativa por electroforesis capilar de zona de mangiferina en tabletas VIMANG® 300 mg / Quantitative determination through capillary zone electrophoresis of mangiferin in 300 mg VIMANG® tablets

La mangiferina se seleccionó como marcador en el control de calidad del ingrediente farmacéutico activo VIMANG® y sus formulaciones, que se han empleado como suplemento nutricional, cosmético y fitomedicamento. El trabajo tuvo como objetivo la validación del método electroforesis capilar para la determinación cuantitativa de mangiferina en la formulación farmacéutica tabletas VIMANG® 300 mg. Se evaluaron la especificidad, linealidad, exactitud y precisión. Los resultados obtenidos demostraron que el método fue específico, al no existir interferencias de los excipientes o sus productos de degradación. La linealidad mostró un coeficiente de correlación de 0,9979 en el intervalo de concentraciones estudiado. Los coeficientes de variación para la repetibilidad y la precisión intermedia fueron menores de 2 por ciento. La exactitud mostró un recobrado del 100,20 por ciento que no difiere significativamente de 100 por ciento En conclusión, el método validado es específico, lineal, preciso y exacto, y constituye una alternativa ventajosa al método cromatografía líquida de alta resolución establecido con anterioridad en el laboratorio

Mangiferin was selected as marker in the quality control of active principle VIMANG® and its formulations, which have been used as nutritional supplement, cosmetic, and phytomedication. This paper was aimed at validating the capillary electrophoresis method for the quantitative analysis of mangiferin in the pharmaceutical formulation 300 mg VIMANG® tablets. The specificity, linearity, accuracy and precision were assessed. The results showed the method specificity owing to lack of interference by the excipients or their degradation products. Linearity showed a correlation coefficient of 0,9979 in the studied concentration range. The variation coefficients for repeatability and intermediate precision were less than 2 percent. Accuracy reached a recovery rate of 100,20 percent that is not statistically different from 100 percent. It may be concluded that the validated method is specific, linear, precise and accurate and could be an advantageous alternative to the high resolution liquid chromatography method used at the lab setting

Effect of beta-mercaptoethanol or epidermal growth factor supplementation on in vitro maturation of canine oocytes collected from dogs with different stages of the estrus cycle

Supplementation of beta-mercaptoethanol (beta-ME) in in vitro maturation (IVM) medium was shown to improve embryo development and quality in several species. Epidermal growth factor (EGF) was also shown to improve IVM of human oocyte and embryo development after in vitro fertilization (IVF). The effect of these two compounds were suggested to be mediated through the synthesis of glutathione (GSH) which is known to play an important role in protecting the cell or embryos from oxidative damage. Thus, it is suggested that supplementation of canine IVM medium with beta-ME or EGF may be of benefit due to its positive role in IVM of various mammalian oocytes and embryo development, including cattle, pigs, rodents and humans. This study investigates the effect of ovarian estrus stage on canine oocyte quality and supplementation of medium with beta-ME or EGF on IVM of canine oocytes. As results, a significantly higher percentage of oocytes progressed to metaphase II (MII) stage in 50 or 100 microM of beta-ME supplemented oocytes collected from the follicular stage. The maturation rate to metaphase I (MI) stage was also significantly higher in oocytes collected from follicular stage and cultured with 25 or 100 microM compared to other experimental groups. After IVM culture, oocytes recovered from dogs with the follicular stage and matured in TCM-199 supplemented with 20 ng/ml EGF yielded better oocyte maturation to MII phase compared to other groups. Taken together, supplementation of beta-ME (50 or 100 microM) or EGF (20 ng/ml) improved IVM of canine oocytes to MII stage.