In the present study, two amphiphilic star-hyperbranched copolymers, poly(methyl methacrylate)-b-poly(2-hydroxyethyl methacrylate) (PMMA-b-PHEMA), with different hydrophilic PHEMA segment content (PMMA-b-PHEMA-1, and PMMA-b-PHEMA-2) were synthesized and their drug loading and release profiles were examined by using paclitaxel (PTX) as a model drug. Drug loading capacity and encapsulation efficiency were found to be similar in both polymers. Encapsulation efficiency found to be prominent with 98% and 98.5% for PMMA-b-PHEMA-1 and PMMA-b-PHEMA-2, respectively. On the other hand, drug release behaviors were varied in favor of the block copolymer comprising shorter PHEMA chains (PMMAb-PHEMA-1). Additionally, to assess biological effects of PTX-loaded polymers, human non-small cell lung carcinoma (A549) cells were used. Cell viability and cell cycle analysis showed that both polymers were not toxic to the cells. Cytotoxic effects of PTX-loaded PMMA-b-PHEMA-1 on A 549 cells were higher (66.49% cell viability at 5.0 ng/mL PTX) than that of PMMA-b-PHEMA-2 (72.47% cell viability at 5.0 ng/mL PTX) consistent with the drug release experiments.

This study involves bibliometric analysis of the scientific researches published in STEM education subject area. For this purpose, 2,313 studies about STEM education, published between 1992 and 2017 were analyzed bibliometrically and the trend of the last 26 years was revealed. Web of Science Core Collection database was scanned for "STEM Education" keyword and bibliometric data belonging to the studies were obtained. The studies were analyzed under the following sub-headings: number of publications per year, types of publications, language of publications, citation analysis, country collaborations, common citation networks and concepttopic tendencies. It is aimed to identify main authors who have conducted researches in the subject area and the works that they have done, as well as to determine the interaction between them. In addition, a word analysis was also conducted within the study in order to determine the concepts used in the researches published in STEM education area and covered in the data set. As a result of the analysis, collaborations and relationship patterns were visualized in the form of cognitive maps. In addition, the layout of the country collaborations, journals, authors, publications and concepts that form the sources of the citations in the network was evaluated.

action for calcitriol will help development of novel treatment strategies. Since vitamin D exerts its cellular actions via binding to its receptor and by altering expressions of a set of genes, we aimed to evaluate the effect of calcitriol on transcriptomic profile of breast cancer cells. We previously demonstrated that calcitriol alters ER stress markers, therefore in this study we have focused on ERstress related genes to reveal calcitriols action on these genes in particular.We have treated breast cancer cell lines MCF-7 and MDA-MB-231 with previously determined IC 50 concentrations of calcitriol and evaluated transcriptomic alterations via microarray.During analysis only genes altered by at least 2 fold with a p value less than 0.05 were taken into consideration.Our findings revealed an ER stress associated transcriptomic profile induced by calcitriol.Induced genes include genes with pro-survival function (NUPR1, DNAJB9, HMOX1, LCN2 and LAMP3) and with pro-death function (CHOP, DDIT4, NDGR1, NOXA and CLGN). These results suggest that calcitriol induces an ER-stress like response inducing both pro-survival and pro-death transcripts of the process.

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