Fig. 4: Scatter diagrams showing the plasma levels of zinc, copper, and zinc/copper of patients with DN.

A Plasma zinc levels were significantly lower in the low-zinc group than in the normal-zinc group (*P < 0.05). B Plasma copper levels were significantly higher in the low-zinc group than in the normal-zinc group (*P < 0.05). C The ratio of zinc and copper in the low-zinc group was significantly lower than that in the normal-zinc group (*P < 0.05).