Reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) provides a valuable opportunity to study neurodevelopmental and neurodegenerative psychiatric diseases by offering an unlimited source for patient-specific neuronal and glial cells. The present review focuses on the recent advancements in modeling psychiatric disorders such as Phelan-McDermid syndrome, Timothy syndrome, Rett syndrome, schizophrenia, bipolar disorder, and dementia. The treatment effects identified in studies on iPSCs using known therapeutic compounds are also summarized in this review. Here we discuss validation of cellular models and explore iPSCs as a novel drug screening tool. Although there are several limitations associated with the current methods used to study mental disorders, using iPSCs as a model system provides the advantage of rewinding and reviewing the development and degeneration of human neural cells.
Bipolar Disorder ; Dementia ; Drug Evaluation, Preclinical ; Humans ; Induced Pluripotent Stem Cells* ; Mental Disorders ; Neuroglia ; Neurons ; Rett Syndrome ; Schizophrenia

OBJECTIVE: This study aimed to characterize the use of medical service and medical costs of each cluster categorized by its discharge disposition pattern. METHOD: Data extracted from Electronic Data Interchange database of Korea Workers' Compensation and Welfare Service was analyzed. Among those who suffered from industrial accidents from Jan 1, 2006 to Dec 31, 2006, 422 were stroke patients. We categorized the subjects into 2 groups using k-means cluster analysis according to the discharge disposition pattern. Demographic characteristics, days of treatment, medical cost, initially admitted medical institution and disease type were analyzed in each group. RESULTS: There was no difference between the 2 groups in age, sex, type of stroke (ischemic or hemorrhagic stroke) and initially admitted medical institution. However medical cost and days of treatment were significantly different between 2 groups. CONCLUSION: K-means cluster analysis according to transferring pattern revealed a distinct group with longer hospitalization and more medical cost in injured workers. Further study is necessary to find out the characteristics of this group.
Accidents, Occupational ; Cluster Analysis ; Electronics ; Electrons ; Hospitalization ; Humans ; Korea ; Stroke ; Workers' Compensation

Objective: The purpose of this finite element method (FEM) study was to analyze the biomechanical differences and tooth displacement patterns according to the traction direction, methods, and sites for total distalization of the mandibular dentition using clear aligner treatment (CAT). Methods: A finite element analysis was performed on four FEM models using different traction methods (via a precision cut hook or button) and traction sites (mandibular canine or first premolar). A distalization force of 1.5 N was applied to the traction site by changing the direction from –30 to +30° to the occlusal plane. The initial tooth displacement and von Mises stress on the clear aligners were analyzed. Results: All CAT-based total distalization groups showed an overall trend of clockwise or counterclockwise rotation of the occlusal plane as the force direction varied. Mesiodistal tipping of individual teeth was more prominent than that of bodily movements. The initial displacement pattern of the mandibular teeth was more predominant based on the traction site than on the traction method. The elastic deformation of clear aligners is attributed to unintentional lingual tipping or extrusion of the mandibular anterior teeth. Conclusions The initial tooth displacement can vary according to different distalization strategies for CAT-based total distalization. Discreet application and biomechanical understanding of traction sites and directions are necessary for appropriate mandibular total distalization.