Neuronal activity disrupts myelinated axon integrity in the absence of NKCC1b

Through a genetic screen in zebrafish, we identified a mutant with disruption to myelin in both the CNS and PNS caused by a mutation in a previously uncharacterized gene, slc12a2b, predicted to encode a Na+, K+, and Cl− (NKCC) cotransporter, NKCC1b. slc12a2b/NKCC1b mutants exhibited a severe and progressive pathology in the PNS, characterized by dysmyelination and swelling of the periaxonal space at the axon–myelin interface. Cell-type–specific loss of slc12a2b/NKCC1b in either neurons or myelinating Schwann cells recapitulated these pathologies. Given that NKCC1 is critical for ion homeostasis, we asked whether the disruption to myelinated axons in slc12a2b/NKCC1b mutants is affected by neuronal activity. Strikingly, we found that blocking neuronal activity completely prevented and could even rescue the pathology in slc12a2b/NKCC1b mutants. Together, our data indicate that NKCC1b is required to maintain neuronal activity–related solute homeostasis at the axon–myelin interface, and the integrity of myelinated axons

Professions and the Pursuit of Transparency in Healthcare: Two Cases of Soft Autonomy

Contemporary professions are increasingly challenged to open up to scrutiny from the outside. Earlier research is focused on two main types of responses and consequences: colonization by a managerial logic of self-monitoring and decoupling of auditing and professional practice. his paper describes a different type of response which implies that professionals get actively involved in monitoring their own activities, without losing their professional autonomy. Two cases from Swedish healthcare were investigated: accreditation at a hospital laboratory and the national quality registries. In both cases, professional involvement took the form of translation and negotiation in expert networks, restrained by a certain resistance towards external monitoring, but driven by an interest in legitimizing and developing professional work. he resulting situation is characterized as a 'soft autonomy' which combines professional internalization of originally non-professional auditing ideas with maintained professional control over evaluation criteria