Experimental biology and medicine
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Exp. Biol. Med. (Maywood) · Oct 2009
Propensity of human embryonic stem cell lines during early stage of lineage specification controls their terminal differentiation into mature cell types.
Human embryonic stem cells (hESCs) are able to stably maintain their characteristics for an unlimited period; nevertheless, substantial differences among cell lines in gene and protein expression not manifested during the undifferentiated state may appear when cells differentiate. It is widely accepted that developing an efficient protocol to control the differentiation of hESCs will enable us to produce adequate numbers of desired cell types with relative ease for diverse applications ranging from basic research to cell therapy and drug screening. Hence of late, there has been considerable interest in understanding whether and how hESC lines are equivalent or different to each other in their in vitro developmental tendencies. ⋯ Upon further differentiation, HUES-9 generated largely neural cells (neurons, oligodendrocytes, astrocytes and gangliosides) whereas HUES-7 formed mesendodermal derivatives, including cardiomyocytes, skeletal myocytes, endothelial cells, hepatocytes and pancreatic cells. Overall, our findings endorse the hypothesis that independently-derived hESCs biologically differ among themselves, thereby displaying varying differentiation propensity. These subtle differences not only highlight the importance of screening and deriving lines for lineage-specific differentiation but also indicate that individual lines may possess a repertoire of capabilities that is unique.
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Exp. Biol. Med. (Maywood) · Oct 2009
Comparative StudyComparison of isoflurane-, sevoflurane-, and desflurane-induced pre- and postconditioning against myocardial infarction in mice in vivo.
The murine in vivo model of acute myocardial infarction is increasingly used to investigate anesthetic-induced preconditioning (APC) and postconditioning (APOST). However, in mice the potency of different volatile anesthetics to reduce myocardial infarct size (IS) has never been investigated systematically nor in a head to head comparison with regard to ischemic preconditioning (IPC) and postconditioning (IPOST). Male C57BL/6 mice were subjected to 45 min of coronary artery occlusion (CAO) and 180 min of reperfusion. ⋯ ISO APC significantly reduced IS compared to control when administered 30 min (33 +/- 4%*), but not when administered 15 min (48 +/- 6%). DES APC significantly reduced IS compared to control and to SEVO APC (7 +/- 1%*). Within the paradigm of preconditioning, the potency of volatile anesthetics to reduce myocardial infarct size in mice significantly increases from ISO over SEVO to DES, whereas within the paradigm of postconditioning the potency of these volatile anesthetics to reduce myocardial infarct size in mice is similar.