Funding for this research was provided by:
Spanish Ministerio de Ciencia e Innovación (CGL2010-16195)
Text and Data Mining valid from 2018-06-19
Received: 10 August 2017
Accepted: 5 June 2018
First Online: 19 June 2018
: VMC is actually retired.
: The procedure of human population sampling adhered to the tenets of the Declaration of Helsinki. Written consent was recorded from all participants prior to taking part in the study. The study underwent formal review and was approved by the College of Medicine Ethical Committee of the King Saud University (proposal N°09-659), and by the Ethics Committee for Human Research at the University of La Laguna (proposal NR157).
: The authors declare that they have no competing interests.
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