11 research outputs found
キンリン ショコク ノ スキ キライ ニ シンブン ホウドウ ガ アタエル エイキョウ
We study to what extent the amount of newspaper reports on China and North and South Korea affect how much Japanese like or dislike these countries. Some news is good news, while others are bad news. Thus, we are not sure whether more reports on a country make people either like or dislike the country under consideration (expected value constant hypothesis). On the other hand, since more reports provide more information, more people change their minds in either direction(variance increase hypothesis)。 We analyze monthly data from 1960 to 2010 and find that these hypotheses are supported. In addition, it turned out that, as trade with a country increases, more peoPle tend to dislike the country in the long run
Enhanced hepatic differentiation in the subpopulation of human amniotic stem cells under 3D multicellular microenvironment
BACKGROUNDTo solve the problem of liver transplantation donor insufficiency, an alternative cell transplantation therapy was investigated. We focused on amniotic epithelial cells (AECs) as a cell source because, unlike induced pluripotent stem cells, they are cost-effective and non-tumorigenic. The utilization of AECs in regenerative medicine, however, is in its infancy. A general profile for AECs has not been comprehensively analyzed. Moreover, no hepatic differentiation protocol for AECs has yet been established. To this end, we independently compiled human AEC libraries, purified amniotic stem cells (ASCs), and co-cultured them with mesenchymal stem cells (MSCs) and human umbilical vein endothelial cell (HUVECs) in a 3D system which induces functional hepatic organoids.AIMTo characterize AECs and generate functional hepatic organoids from ASCs and other somatic stem cellsMETHODSAECs, MSCs, and HUVECs were isolated from the placentae and umbilical cords of cesarean section patients. Amnion and primary AEC stemness characteristics and heterogeneity were analyzed by immunocytochemistry, Alkaline phosphatase (AP) staining, and flow cytometry. An adherent AEC subpopulation was selected and evaluated for ASC purification quality by a colony formation assay. AEC transcriptomes were compared with those for other hepatocytes cell sources by bioinformatics. The 2D and 3D culture were compared by relative gene expression using several differentiation protocols. ASCs, MSCs, and HUVECs were combined in a 3D co-culture system to generate hepatic organoids whose structure was compared with a 3D AEC sphere and whose function was elucidated by immunofluorescence imaging, periodic acid Schiff, and an indocyanine green (ICG) test.RESULTSAECs have certain stemness markers such as EPCAM, SSEA4, and E-cadherin. One AEC subpopulation was also either positive for AP staining or expressed the TRA-1-60 and TRA-1-81 stemness markers. Moreover, it could form colonies and its frequency was enhanced ten-fold in the adherent subpopulation after selective primary passage. Bioinformatics analysis of ribose nucleic acid sequencing revealed that the total AEC gene expression was distant from those of pluripotent stem cells and hepatocytes but some gene expression overlapped among these cells. TJP1, associated with epidermal growth factor receptor, and MET, associated with hepatocyte growth factor receptor, were upregulated and may be important for hepatic differentiation. In conventional flat culture, the cells turned unviable and did not readily differentiate into hepatocytes. In 3D culture, however, hepatic gene expression of the AEC sphere was elevated even under a two-step differentiation protocol. Furthermore, the organoids derived from the MSC and HUVEC co-culture showed 3D structure with polarity, hepatic-like glycogen storage, and ICG absorption/elimination.CONCLUSIONHuman amniotic epithelial cells are heterogeneous and certain subpopulations have high stemness. Under a 3D co-culture system, functional hepatic organoids were generated in a multicellular microenvironment