Increased whitening efficacy and reduced cytotoxicity are achieved by the chemical activation of a highly concentrated hydrogen peroxide bleaching gel

Abstract Objective This study was designed for the chemical activation of a 35% hydrogen peroxide (H2O2) bleaching gel to increase its whitening effectiveness and reduce its toxicity. Methodology First, the bleaching gel - associated or not with ferrous sulfate (FS), manganese chloride (MC), peroxidase (PR), or catalase (CT) - was applied (3x 15 min) to enamel/dentin discs adapted to artificial pulp chambers. Then, odontoblast-like MDPC-23 cells were exposed for 1 h to the extracts (culture medium + components released from the product), for the assessment of viability (MTT assay) and oxidative stress (H2DCFDA). Residual H2O2 and bleaching effectiveness (DE) were also evaluated. Data were analyzed with one-way ANOVA complemented with Tukey's test (n=8. p<0.05). Results All chemically activated groups minimized MDPC-23 oxidative stress generation; however, significantly higher cell viability was detected for MC, PR, and CT than for plain 35% H2O2 gel. Nevertheless, FS, MC, PR, and CT reduced the amount of residual H2O2 and increased bleaching effectiveness. Conclusion Chemical activation of 35% H2O2 gel with MC, PR, and CT minimized residual H2O2 and pulp cell toxicity; but PR duplicated the whitening potential of the bleaching gel after a single 45-minute session.

Género y trayectorias profesionales de las médicas de familia en Andalucía, España, a comienzos del siglo XXI / Gender and career paths of female primary care physicians in Andalusia, Spain, at the beginning of 21st century

El objetivo de este trabajo es estudiar, desde una perspectiva feminista, la diversidad y homogeneidad en las trayectorias profesionales de las médicas de familia que ejercían en Andalucía a comienzos del siglo XXI, a través del análisis de los significados que ellas mismas confieren a su desarrollo profesional y de la influencia de los factores personales, familiares y laborales. Realizamos un estudio cualitativo con seis grupos de discusión. Participaron 32 médicas de familia que se encontraban trabajando en los centros de salud urbanos de la red sanitaria pública de Andalucía. El análisis del discurso revela que la mayoría de las médicas no planifican sus metas profesionales y que, cuando lo hacen, las van entrelazando con las necesidades familiares. Esto se traduce en que sus trayectorias profesionales sean discontinuas. Por el contrario, las trayectorias orientadas al desarrollo profesional y a la planificación consciente de metas son más frecuentes entre las médicas que ocupan cargos de dirección en centros de salud.

The purpose of this article was to study, from a feminist perspective, the diversity and homogeneity in the career paths of female primary care physicians from Andalusia, Spain in the early 21st century, by analyzing the meanings they give to their careers and the influence of personal, family and professional factors. We conducted a qualitative study with six discussion groups. Thirty-two female primary care physicians working in urban health centers of the public health system of Andalusia participated in the study. The discourse analysis revealed that most of the female physicians did not plan for professional goals and, when they did plan for them, the goals were intertwined with family needs. Consequently, their career paths were discontinuous. In contrast, career paths oriented towards professional development and the conscious planning of goals were more common among the female doctors acting as directors of health care centers.

Heat-treated hull flour does not affect iron bioavailability in rats / Farinha de soja com casca tratada termicamente

In this study the chemical composition and iron bioavailability of hull and hull-less soybean flour from the new cultivar UFVTN 105AP was evaluated. The hemoglobin depletion-repletion method was used in Wistar rats. Soybean hull flour presented 37% more total dietary fiber and higher content of iron than hull-less soybean flour. The phytate:iron molar ratio, however, was 2-fold lower in the soybean hull flour in compared to the hull-less soybean flour. Animals fed soybean hull flour presented hemoglobin gains similar to those of the control diet group (p>0.05). The Relative Biological Values of hull and hull-less soybean flour were 68.5% and 67.1%, respectively, compared to the control group. Heat-treated soybean hull flour (150ºC/30 minutes) showed high content of iron and low phytate, which favors the iron bioavailability. Thus, the soybean hull flour is a better source of dietary fiber and iron than hull-less soybean flour at comparable bioavailabilities.

Neste estudo foram avaliadas a composição química e a biodisponibilidade de ferro das farinhas de soja com e sem casca do novo cultivar UFVTN 105AP. O método usado foi de depleção-repleção de hemoglobina em ratos Wistar. A farinha de soja com casca apresentou 37% a mais de fibra alimentar e maior teor de ferro (p 0,05). O Valor Relativo de Biodisponibilidade (VRB) da farinha de soja com casca e sem casca foram 68,5% e 67,1%, respectivamente, em relação ao sulfato ferroso (100%). A farinha de soja com casca submetida ao tratamento térmico (150ºC/30 minutos) apresentou maior teor de ferro e reduzido conteúdo de fitato, favorecendo a biodisponibilidade de ferro. Assim, a farinha de soja com casca apresentou melhor fonte de fibra alimentar e ferro do que a farinha de soja sem casca de comparável biodisponibilidade.

Colour and COD removal from pulp and paper mill effluent by q Fenton's oxidation.

Colour and COD removal studies of pulp and paper mill effluent were carried out by Fenton's oxidation. Fenton's oxidation process was employed in four distinct stages interrelated to each other. In the first stage, FeSO4 concentration, pH and temperature were kept constant to determine H2O2 dose for maximum color and COD removal. In the second stage, dose of H2O2 obtained from first stage and same oxidation conditions were applied to determine the optimum FeSO4 concentration. Optimum pH, temperature and contact time were investigated in third and fourth stages considering the results of optimum doses of first and second stage. Maximum color up to 98% and COD removal up to 62% were obtained for Fenton reagents of 600 mg/L of H2O2 and 100 mg/L of Fe2+ dose at pH 3.0 for 300 min of contact period between reagents and effluent.