Develop a 3D Neurological Disease Model of Human Cortical Glutamatergic Neurons Using Micropillar-Based Scaffolds

Establishing an effective three-dimensional (3D) in vitro culture system to better model human neurological diseases is desirable, since the human brain is a 3D structure. Here, we demonstrated the development of a polydimethylsiloxane (PDMS) pillar-based 3D scaffold that mimicked the 3D microenvironment of the brain. We utilized this scaffold for the growth of human cortical glutamatergic neurons that were differentiated from human pluripotent stem cells. In comparison with the 2D culture, we demonstrated that the developed 3D culture promoted the maturation of human cortical glutamatergic neurons by showing significantly more MAP2 and less Ki67 expression. Based on this 3D culture system, we further developed an in vitro disease-like model of traumatic brain injury (TBI), which showed a robust increase of glutamate-release from the neurons, in response to mechanical impacts, recapitulating the critical pathology of TBI. The increased glutamate-release from our 3D culture model was attenuated by the treatment of neural protective drugs, memantine or nimodipine. The established 3D in vitro human neural culture system and TBI-like model may be used to facilitate mechanistic studies and drug screening for neurotrauma or other neurological diseases

Equitable Coloring of IC-Planar Graphs with Girth g ≥ 7

An equitable k-coloring of a graph G is a proper vertex coloring such that the size of any two color classes differ at most 1. If there is an equitable k-coloring of G, then the graph G is said to be equitably k-colorable. A 1-planar graph is a graph that can be embedded in the Euclidean plane such that each edge can be crossed by other edges at most once. An IC-planar graph is a 1-planar graph with distinct end vertices of any two crossings. In this paper, we will prove that every IC-planar graph with girth g≥7 is equitably Δ(G)-colorable, where Δ(G) is the maximum degree of G

Planar Graphs of Maximum Degree Six without 7-cycles are Class One

In this paper, we prove that every planar graph of maximum degree six without 7-cycles is class one.</jats:p

DP-coloring on planar graphs without given adjacent short cycles

DP-coloring (also known as correspondence coloring) introduced by Dvor̆ák and Postle (2015) is a generalization of list coloring. In 2019, Chen et al. showed that planar graphs without [Formula: see text]-cycles adjacent to [Formula: see text]-cycles are DP-[Formula: see text]-colorable for [Formula: see text] and [Formula: see text]. In this paper, we will prove that planar graphs without [Formula: see text]-cycles adjacent simultaneously to [Formula: see text]-cycles and [Formula: see text]-cycles are DP-[Formula: see text]-colorable, which is an extension of the above result. </jats:p