Astrocytic Ephrin-B1 Regulates Oligodendrocyte Development and Myelination.

Astrocytes have been implicated in oligodendrocyte development and myelination, however, the mechanisms by which astrocytes regulate oligodendrocytes remain unclear. Our findings suggest a new mechanism that regulates astrocyte-mediated oligodendrocyte development through ephrin-B1 signaling in astrocytes. Using a mouse model, we examined the role of astrocytic ephrin-B1 signaling in oligodendrocyte development by deleting ephrin-B1 specifically in astrocytes during the postnatal days (P)14-P28 period and used mRNA analysis, immunohistochemistry, and mouse behaviors to study its effects on oligodendrocytes and myelination.

Objective Evaluation of Motor Skills for Orthopedic Residents Using a Motion Tracking Drill System: Outcomes of an ABOS Approved Surgical Skills Training Program.

Background: Orthopedics is a motor skills-demanding surgical specialty requiring surgical skills training outside of the operating room. Unfortunately, limited quantitative techniques exist to determine the effectiveness of these surgical skills training programs. Using a variety of drill, surgeon, and specimen mounted sensors, we evaluated orthopedic surgery residents during a surgical skills training course approved by the American Board of Orthopaedic Surgeons (ABOS).