(a) H&E staining of paraffin-fixed liver tissues: control (A), one day (D1, B), two days (D2, C), seven days (D7, C). Prussian blue staining of fixed paraffin-embedded liver tissues: control (E), one day (D1, F), two days (D2, G), seven days (D7, H). (b) in vivo gene transfection of liver with control (A) at one day (D1, B), two days (D2, C) and seven days (D7, D); in vivo gene transfection of prostate with control (E) at one day (D1, F), two days (D2, G) and seven days (D7, H)