Also, the data show that there is a decrease in Oct4 mRNA after plating. Similarly, Nanog’s mRNA was 15-fold in normal rat liver, again indicating a drop in Nanog levels after plating. These data for Oct4 and Nanog mRNA in Fig. 7A support their high protein levels seen at day 0 (2 hours after plating) in the buy Crenolanib initial experiment (Fig. 2). Hepatocytes cultured with growth factors brought
back these levels, in contrast to hepatocytes cultured without the growth factors. The present data signify the fact that even though the expression of these reprogramming factors in cultures with GF is not comparable to MESC, the level of expression is nevertheless important for the proliferation and normal survival of these hepatocytes in culture. We also found that these reprogramming factors are up-regulated after PHx DMXAA as seen by qRT-PCR, western blot, and IHC. In fact, the expression of REST and Oct4 is close to that of MESC,
whereas that of Myc is more than that in MESC (Fig. 7D,E). In view of our results with hepatocytes in culture, it is reasonable to speculate that they may play a role in liver regeneration in vivo as well. The fact that primary hepatocytes express these reprogramming factors but are not acting as stem cells is intriguing. The mechanism(s) that inhibit hepatocytes from behaving like stem cells in spite of expressing reprogramming factors is unknown and it probably relates to relative levels of expression. On the other hand, previous studies have shown that hepatocytes can transdifferentiate to biliary epithelial cells in vivo.21 Other studies have also shown that mouse22 and rat hepatocytes have a high capacity of clonal growth in recolonization of liver of mice with FAH deficiency.23-25 In these studies it was estimated that one mouse hepatocyte was MCE capable of generating 50 mouse livers. It is conceivable that the coordinated and growth factor-induced expression of REST and the reprogramming factors underlies the capacity
of hepatocytes for such high clonal growth, documented in several models of liver recolonization.26-28 It is also possible, however, that the expression of reprogramming factors may occur in other cell types under normal growth conditions. Our studies should prompt further investigation of both of these possibilities. We thank John Stoops for assistance with the partial hepatectomy experiments. Additional Supporting Information may be found in the online version of this article. “
“Background and Aim: Although narrow-band imaging (NBI) is used increasingly in clinical situations, the significance of each NBI finding has not been investigated. The primary endpoint of the present study was to identify the significant NBI findings to diagnose esophageal mucosal high-grade neoplasia. Methods: Between August 2007 and January 2009, we detected 59 new superficial esophageal lesions. The video images of NBI were recorded digitally.