Abstract Objectives The endogenous repairing based on the activation of neural stem cells (NSCs) is impaired by neurodegenerative diseases. The present study aims to characterize human stem cells from the apical papilla (hSCAPs) with features of mesenchymal stem cells (MSCs) and to demonstrate the neuronal differentiation of hSCAPs into NSCs through the formation of three-dimensional (3D) neurospheres, verifying the structural, immunophenotyping, self-renewal, gene expression and neuronal activities of these cells to help further improve NSCs transplantation. Methodology The hSCAPs were isolated from healthy impacted human third molar teeth and characterized as MSCs. They were then induced into 3D-neurospheres using a specific neural induction medium. Subsequently, the intra-neurospheral cells were confirmed to be NSCs by the identification of Nissl substance and the analysis of immunofluorescence staining, self-renewal ability, and gene expression of the cells. Moreover, the neuronal activity was investigated using intracellular calcium oscillation. Results The isolated cells from the human apical papilla expressed many markers of MSCs, such as self-renewal ability and multilineage differentiation. These cells were thus characterized as MSCs, specifically as hSCAPs. The neurospheres induced from hSCAPs exhibited a 3D-floating spheroidal shape and larger neurospheres, and consisted of a heterogeneous population of intra-neurospheral cells. Further investigation showed that these intra-neurospheral cells had Nissl body staining and also expressed both Nestin and SOX2. They presented a self-renewal ability as well, which was observed after their disaggregation. Their gene expression profiling also exhibited a significant amount of NSC markers (NES, SOX1, and PAX6). Lastly, a large and dynamic change of the fluorescent signal that indicated calcium ions (Ca2+) was detected in the intracellular calcium oscillation, which indicated the neuronal activity of NSCs-derived hSCAPs. Conclusions The hSCAPs exhibited properties of MSCs and could differentiate into NSCs under 3D-neurosphere generation. The present findings suggest that NSCs-derived hSCAPs may be used as an alternative candidates for cell-based therapy, which uses stem cell transplantation to further treat neurodegenerative diseases. (NSCs diseases (hSCAPs (MSCs threedimensional three dimensional 3D D (3D structural immunophenotyping selfrenewal, selfrenewal self renewal, renewal 3Dneurospheres Dneurospheres medium Subsequently intraneurospheral intra neurospheral Moreover oscillation 3Dfloating Dfloating floating SOX2 SOX well disaggregation NES, NES (NES SOX1 PAX6. PAX6 PAX . PAX6) Lastly Ca2+ Ca2 Ca (Ca2+ NSCsderived derived 3Dneurosphere Dneurosphere neurosphere generation cellbased therapy (Ca2 (Ca

The United States has always been a nation of immigrants, and immigration policy has always been controversial. The history of immigration in the United States is contrasted in this article with a normative standard of naturalization (immigration policy) based on the Declaration of Independence. The current immigration debate fits within a historical pattern that pits an unrestricted right of immigration (the left) against exclusive, provincial politics (the right). Both sides are simultaneously correct and incorrect. A moderate policy on immigration is possible if the debate in the United States gets an infusion of what Thomas Paine called "common sense".

Estados Unidos ha sido siempre una nación de inmigrantes, y su política respecto de la inmigración siempre ha sido controversial. En este artículo se compara la historia de la inmigración con la normativa estándar de naturalización (política de inmigración), basada en la Declaración de Independencia. El debate actual al respecto entra en un patrón histórico que contrapone el derecho irrestricto a la inmigración (la izquierda) con una política provincial excluyente (la derecha). Ambas posturas son a la vez correctas e incorrectas. Una política moderada de inmigración es posible si el debate en Estados Unidos adquiere lo que Thomas Paine llamaba "sentido común".