Received: 5 February 2019
Accepted: 18 April 2019
First Online: 3 May 2019
Ethics approval and consent to participate
: The experiments conformed to the principles of the Declaration of Helsinki and were approved bythe ethics committee of the University of Campania “Luigi Vanvitelli”. All participants provided informed written consent after the experimental procedure had been explained.
: All authors have read and approved this version of the manuscript. These data have not been published previously, nor is the paper under consideration by any other journal. In addition, there has been no ghost writing by anyone not named on the author list.
: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article:Doctor Russo has received speaker honoraria from Allergan and serves as an associate editor of Frontiers in Neurology (Headache Medicine and Facial Pain session).Professor Tessitore has received speaker honoraria from Novartis, Schwarz Pharma/UCB, Lundbeck, Abbvie and Glaxo.Professor Tedeschi has received speaker honoraria from Sanofi-Aventis, Merck Serono, Bayer Schering Pharma, Novartis, Biogen-Dompe´ AG; has received funding for travel from Bayer Schering Pharma, Biogen-Dompe´ AG, Merck Serono, Novartis and Sanofi Aventis; and serves as an associate editor of Neurological Sciences.The other authors have nothing to declare.
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