Signaling through ERK1/2 controls myelin thickness during myelin repair in the adult central nervous system.

Oligodendrocytes, the myelin-forming cells of the CNS, exquisitely tailor the thickness of individual myelin sheaths to the diameter of their target axons to maximize the speed of action potential propagation, thus ensuring proper neuronal connectivity and function. Following demyelinating injuries to the adult CNS, newly formed oligodendrocytes frequently generate new myelin sheaths. Following episodes of demyelination such as those that occur in patients with multiple sclerosis, however, the matching of myelin thickness to axon diameter fails leaving remyelinated axons with thin myelin sheaths potentially compromising function and leaving axons vulnerable to damage.

Differences in evidence-based care in midwifery practice and education.

Purpose: To examine site-specific differences in managing labor and to describe variations in intrapartum practice in the context of clinical midwifery education.

Design: Descriptive design based on secondary analysis of an existing data set collected to evaluate the intrapartum clinical experiences of nurse-midwifery students. The data set included 498 records collected by midwifery students in 23 sites from 1995-1998.