PRRT2 Is a Key Component of the Ca2+-Dependent Neurotransmitter Release Machinery

Heterozygous mutations in proline-rich transmembrane protein 2 (PRRT2) underlie a group of paroxysmal disorders, including epilepsy, kinesigenic dyskinesia, and migraine. Most of the mutations lead to impaired PRRT2 expression, suggesting that loss of PRRT2 function may contribute to pathogenesis. We show that PRRT2 is enriched in presynaptic terminals and that its silencing decreases the number of synapses and increases the number of docked synaptic vesicles at rest. PRRT2-silenced neurons exhibit a severe impairment of synchronous release, attributable to a sharp decrease in release probability and Ca2+ sensitivity and associated with a marked increase of the asynchronous/synchronous release ratio. PRRT2 interacts with the synaptic proteins SNAP-25 and synaptotagmin 1/2. The results indicate that PRRT2 is intimately connected with the Ca2+-sensing machinery and that it plays an important role in the final steps of neurotransmitter release

Does Social Isolation Affect Medical Doctor Visits? New Evidence Among European Older Adults

We aimed to determine whether social isolation is associated with higher health-care utilization among European older adults. We have used panel data (2004-2015) from the Survey of Health, Ageing and Retirement in Europe (SHARE) to examine the impact of social isolation on general practitioner health-care use. More precisely, we have considered negative binomial panel count data models to study the main driving factors. Socio-demographic, health, and social isolation measures are analyzed. Differences by Welfare Regimes have been also considered. Using two definitions of social isolation (Alone and Help), we have found that a sizeable proportion of those aged 50 years and older in Europe reported social isolation. Our results showed that while nonpartnership was significantly and positively correlated with health-care utilization (B = 0.03), providing help was significantly and negatively related with physician visits considering the full sample of European countries (B = -0.09). Differences by Welfare Regimes are highlighted. Also, Mediterranean countries consume more health-care services than other European ones. Targeting interventions for social isolated elders may significantly decrease general practitioner consultations and so health-care costs. Our findings provide several implications in current debates on the sustainability of welfare states