Received: 17 January 2018
Accepted: 17 October 2018
First Online: 6 November 2018
Ethics approval and consent to participate
: Written informed consent was obtained from each subject and the study protocol was approved by the local committee of the Department of Internal Medicine and Medical Specialties University Hospital (Policlinico “Umberto I” viale del Policlinico 155, 00161) Rome, 6 December 2001.
: Not applicable.
: The authors declare that they have no competing interests.
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