[Changes of ABH substances amount in human tissues after treatment with physico-chemical factors]

The forensic samples for identify testing are always affected by the environmental or the physico-chemical influence. The aim of the present study is to study whether the physico-chemical or biological factors affect the quantity of ABH substances in human tissues or not. The quantity of the ABH substances was determined by immunohistochemical ABC method. The tissues were treated by a series of methods, including immersing in water, treatment with heat, acid, alkali as well as putrefaction and mold growing. The results revealed that although the ABH substances slightly decreased in some tissues pretreated, no effect of ABO typing was observed. The correct ABO typing was performed with tissues under the following condition: the tongue and skin immersed in water for 21 days; the tongue treated with heat (100 degrees C) for 40 min; the tongue and skin treated with 0.2mol/L HCl and 0.2 mol/L NaOH for 48 h and the skin treated with 12mol/L HCl and 12mol/L NaOH for 30 min. The ABO typing of pancreas undergoing putrefaction and mold growing 21 days was carried out correctly. It is concluded that the ABC immunohistochemical technique is a good method for ABO typing of human tissues.