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Conventional methods for obtaining pancreatic beta cells are based on simulating the embryonic development phase of endocrine cells via hierarchical differentiation of pluripotent stem cells (PSCs). Accordingly, we attempted to modify the protocols for obtaining insulin-secreting cells (ISCs) by sequential differentiation of a human embryonic stem cell (hESC), using the HS181 cell line. Furthermore, we hypothesize that actual pancreatic endocrine cells may arise from trans-differentiation of mature ductal cells after the embryonic developmental stage and throughout the rest of life. According to the hypothesis, ductal cells are trans-differentiated into endocrine and exocrine cells, undergoing a partial epithelial to mesenchymal transition (EMT). To address this issue, we developed two new protocols based on hESC differentiation to obtain ductal cells and then induce EMT in cells to obtain hormone-secreting islet-like cells (HSCs). The ductal (pre-EMT exocrine) cells were then induced to undergo partial EMT by treating with Wnt3a and activin A, in hypoxia. The cell derived from the latter method significantly expressed the main endocrine cell-specific markers and also beta cells, in particular. These experiments not only support our hypothetical model but also offer a promising approach to develop new methods to compensate beta cell depletion in patients with type 1 diabetes mellitus (T1DM). Although this protocol of generating islet-like cells from ductal cells has a potential to treat T1DM, this strategy may be exploited to optimize the function of these cells in an animal model and future clinical applications.

Colorectal cancer (CRC) is one of the most common types of cancer which affects the colon and the rectum. Approximately one third of annual CRC mortality occurs due to the late detection of this type of cancer. Therefore, there is an urgent need for more powerful diagnostic and prognostic tools for identification and treatment of colorectal tumorigenesis. Non-coding RNAs (ncRNAs) have been implicated in the pathology of CRC and also linked to metastasis, proliferation, differentiation, migration, angiogenesis and apoptosis in numerous cancers. Recently, attention has turned towards ncRNAs as specific targets for diagnosis, prognosis and treatment of various types of cancers, including CRC. In this review, we have tried to outline the roles of ncRNAs, and their involvement in signaling pathways responsible for the progression of CRC.

The WKB method is a powerful tool to obtain solutions for Eigenvalue problems. We apply the WKB method to the bifurcation analysis of everted a spherical shells composed of Varga material. Incompressible cases are considered. The method is degenerate but we obtain explicit bifurcation criteria and compare with previous numerical approximations.

Hydro-power plants, as a part of infrastructure projects, play an important role in the economic-social development of countries. Sincea large amount of investment is needed for construction of these power plants, which appeared to be an obstacle in these developments,however it is possible to finance these infrastructure plants by assigning these affairs to private sectors by using build operate transfer(BOT) method, which is quite well-known all around the world. This paper reviews the structure of BOT contracts and through aneconomic evaluation based on different percentage of investments of private sector in providing the expenses of small and mediumhydro-power plants (S&M-HPP) (e.g. MHPP in ‘‘Bookan, Iran’’ and SHPP in ‘‘Nari, Iran’’), demonstrates that by increasing thepercentage the share of the private sector in the investment, the economic indices B/C and NPV improve substantially.r 2006 Elsevier Ltd. All rights reserved.

International audience

International audience

International audience