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Ependymal cells are indispensable components of the central nervous system (CNS). They originate from neuroepithelial cells of the neural plate and show heterogeneity, with at least three types that are localized in different locations of the CNS. As glial cells in the CNS, accumulating evidence demonstrates that ependymal cells play key roles in mammalian CNS development and normal physiological processes by controlling the production and flow of cerebrospinal fluid (CSF), brain metabolism, and waste clearance. Ependymal cells have been attached to great importance by neuroscientists because of their potential to participate in CNS disease progression. Recent studies have demonstrated that ependymal cells participate in the development and progression of various neurological diseases, such as spinal cord injury and hydrocephalus, raising the possibility that they may serve as a potential therapeutic target for the disease. This review focuses on the function of ependymal cells in the developmental CNS as well as in the CNS after injury and discusses the underlying mechanisms of controlling the functions of ependymal cells.

Iodine is an element of fascinating chemical complexity, and numerous hypervalent iodine compounds reveal vital value of applications in organic synthesis. Investigation of the synthesis and application of new type of hypervalent iodine compound has extremely significant meaning. Here, the formation of CsIn (n > 1) compounds is predicted up to 200 GPa using an effective algorithm. The current results show that CsI3 with space group of Pm-3n is thermodynamically stable under high pressure. Hypervalence phenomenon of iodine atoms in Pm-3n CsI3 with endless linear chain type structure appears under high pressure, which is in sharp contrast to the conventional understanding. Our study further reveals that Pm-3n CsI3 is a metallic phase with several energy bands crossing Fermi-surface, and the pressure creates a peculiar reverse electron donation from iodine to cesium. The electron-phonon coupling calculations have proposed superconductive potential of the metallic Pm-3n CsI3 at 10 GPa which is much lower than that of CsI (180 GPa). Our findings represent a significant step toward the understanding of the behavior of iodine compounds at extreme conditions.

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Myelination is an important process in the central nervous system (CNS). Oligodendrocytes (OLs) extend multiple layers to densely sheath on axons, composing the myelin to achieve efficient electrical signal conduction. The myelination during developmental stage maintains a balanced state. However, numerous CNS diseases including neurodegenerative and cerebrovascular diseases cause demyelination and disrupt the homeostasis, resulting in inflammation and white matter deficits. Effective clearance of myelin debris is needed in the region of demyelination, which is a key step for remyelination and tissue regeneration. Microglia and astrocytes are the major resident phagocytic cells in the brain, which may play different or collaborative roles in myelination. Microglia and astrocytes participate in developmental myelination through engulfing excessive unneeded myelin. They are also involved in the clearance of degenerated myelin debris for accelerating remyelination, or engulfing healthy myelin sheath for inhibiting remyelination. This review focuses on the roles of microglia and astrocytes in phagocytosing myelin in the developmental brain and diseased brain. In addition, the interaction between microglia and astrocytes to mediate myelin engulfment is also summarized.