Trib2 regulates the pluripotency of embryonic stem cells and enhances reprogramming efficiency

Embryonic stem (ES) cells are pluripotent cells characterized by self-renewability and differentiation potential. Induced pluripotent stem (iPS) cells are ES cell-equivalent cells derived from somatic cells by the introduction of core reprogramming factors. ES and iPS cells are important sources for understanding basic biology and for generating therapeutic cells for clinical applications. Tribbles homolog 2 (Trib2) functions as a scaffold in signaling pathways. However, the relevance of Trib2 to the pluripotency of ES and iPS cells is unknown. In the present study, we elucidated the importance of Trib2 in maintaining pluripotency in mouse ES cells and in generating iPS cells from somatic cells through the reprogramming process. Trib2 expression decreased as ES cells differentiated, and Trib2 knockdown in ES cells changed their colony morphology while reducing the activity of alkaline phosphatase and the expression of the pluripotency marker genes Oct4, Sox2, Nanog and Klf4. Trib2 directly interacted with Oct4 and elevated Oct4 promoter activity. During the generation of iPS cells, Trib2 knockdown decreased the reprogramming efficiency of mouse embryonic fibroblasts, whereas Trib2 overexpression significantly increased their reprogramming efficiency. In summary, our results suggest that Trib2 is important for maintaining self-renewal in ES cells and for pluripotency induction during the reprogramming process.

Analysis of Reasons for Continuing Education in Dietitians

This study analyzed the reasons for continuing education among dietitians. An internet-based survey of 622 dieticians was conducted from August 31, 2012 to September 12, 2012. Based on data from the Participation Reasons Scale (PRS) questionnaire, factor analysis was conducted by principle component analysis for the extraction of major factors. Subsequent reliability analysis was performed by assessing Cronbach's alpha. The ANOVA-test was performed to compare the participation reason scores for each factors according to general characteristics. Statistical analysis was performed using SPSS ver.17.0, and P<0.05 was considered significant. Factor analysis for the participation reasons revealed four types of factors. These factors were "maintenance and development of professional competencies", "interaction and responsibility of professionals", "job stability and personal profits" and "services for customers" respectively. Among the participation reasons, "maintenance and development of professional competencies" was the first reason with a 29.34% variance. In addition, the participation reasons for continuing education differed according to age (P<0.05), the highest level of education (P<0.05), workplace (P<0.01), and work experience in dietetic area (P<0.001). In conclusion, continuing education programs for dietitians should focus on effectively developing and promoting professionalism.