From: Down-regulation of MicroRNA-21 Is Involved in the Propofol-induced Neurotoxicity Observed in Human Stem Cell–derived Neurons Anesthes. 2014;121(4):786-800. doi:10.1097/ALN.0000000000000345 Figure Legend: Differentiation and characterization of human embryonic stem cell (hESC)–derived neurons. (A) A four-step differentiation protocol was used to generate neurons from the hESCs, which included embryoid body culture, rosette formation, expansion of neural stem cells, and neuron differentiation. (B) The differentiated cells displayed a morphology characteristic of neurons with small cell bodies and projections (a) and stained positive for the neuron-specific markers, microtubule-associated protein 2 (MAP2, b, green), and β-tubulin III (c, green). The blue dots are the cell nuclei stained with Hoechst 33342. (C) The neurons also stained positive for doublecortin (a, green), a marker of immature neurons and again for β-tubulin III (b, red). The doublecortin staining colocalized with the β-tubulin III staining (c, orange). (D) Finally, synapse-like structures were visible in the differentiated neurons (indicated by the yellow arrow) upon electron microscopy imaging. Date of download: 12/29/2017 Copyright © 2017 American Society of Anesthesiologists. All rights reserved.