1Alpha Young LLC, Carlsbad, CA, USA 2Division of Nephrology and Section of Mineral Metabolism, Department of Medicine, Heersink School of Medicine, The University of Alabama at Birmingham, Birmingham, AL, USA. aCorrespondence: Christian Faul, PhD, Tinsley Harrison Tower 611L, 1720 2nd Avenue South, Birmingham, AL 35294, USA, Telephone: 205-996-9641, Fax: 205-996-6650, Email: [email protected]