Lower serum insulin-like growth factor 2 level in patients with bipolar disorder is associated with the severity of manic symptoms during manic episodes. - Shi-Yi Ye; Ying Zhao; Zhao-Bo Liu; Cui-Pin Luo; Jian-Wen Xiong; Jin-Qiong Zhan; Yi-Heng Li; Bo Wei; Chun-Nuan Chen; Yuan-Jian Yang (Frontiers in psychiatry, 2024)