Poetsch, Micaela http://orcid.org/0000-0003-1364-6487
Konrad, Helen
Helmus, Janine
Bajanowski, Thomas
von Wurmb-Schwark, Nicole
Article History
Received: 24 November 2015
Accepted: 25 February 2016
First Online: 14 March 2016
Compliance with ethical standards
: All samples were obtained after informed consent and with approval of the Medical Ethics Committee at the University of Duisburg-Essen in accordance with the Declaration of Helsinki and national laws.