Abstract:Oxidatively modification of low density lipoprotein(LDL) could contribute to theatherosclerotic process by its cytotoxic effect,e.g.being uptaked by the macrophage sca-venger receptor,accelerating the foam cell formation and the influencing on monocyte andmacrophage mobility.The aim of present study is to examine the effect of different con-centrations of vitamine C on Cu²⁺-induced oxidative modification of LDL.As evidencedby the lipid peroxide content,lipofusion and the elec trophoretic mobility,vitamine C could inhibit the oxidative modification of LDL for 24h. The extent of the inhibition depended on vitamine C concentration. These findings indicate that vitamine C is a potentantio-xidant in vivo, it can protect LDL from oxidative modification. Hence, vitamine C can prevent and treat atherosclerosis.

Abstract:Synthetic benzylisoquine compound D₂₀ exibites stronger inhibition on CaM-activatedphosphodiesterase than TFP.IC₅₀=5μmol/L.Flourescence analysis indicats that the asso-ciation constant (K_a) for the interaction between CaM and compound D₂₀ is 2.64(μmol/L)^-1 and compound D₂₀ molecule possesses 2 binding sites for CaM.Binding style is discussed.

Abstract:To elucitate characteristics of the novel GGTP specific to liver cancer cells,GGTPsfrom human fetal liver and hepatoma tissues were purified by Triton X-100 and deoxy-cholate extraction,cold acetone precipitation,glutathione treatment and bromelain digestionfollowed by Sephadex G-150 gel filtration and DEAE-cellulose DE-52 chromatography. The enzymes purified from two sources displayed a pI of 4.2 and an apparent M_r ofabout 92kD,as judged by polyacrylamide gel electrophoresis,which consists of two non-identical glucopeptides with M_r of 64 kD and 27 kD, respectively. The purified GGTPs were used to produce antibodies in rabbits. The antisera with titers of 1:16 were observed to be capable of being absorbed by the constituents of the novel GGTP, Ⅱ and Ⅱ', in sera of patients with hepatoma. Furthermore, they could form in the double diffusion test a smoothly fused precipitating line with two kinds of purified antigens. These results show that GGTPs from human hepatoma and fetal liver tissues are of immunological identity.