This paper is to report our method to extract a fairly purified lymphocyte chalone-like factor from pig spleen and our observation on its properties and actions.An acetone powder was prepared from pig spleen and it was extracted with redistilled water. After ultracentrifugation, the supernatant was ultrafiltrated and the filtrate was called fraction B. Fraction B was further fractionated by chromato-graphy on Sephadex G-25 Column. 7 peaks were obtained(SP1-SP7)and the strongest biological activity was found in the fraction SP2. It is the lymphocyte chalone-like factor and its molecular weight is 1400.The actions of this lymphocyte chalone was not affected in the condition of incubation when the calf serum of the culture medium was subsituted with human calf serum or different doses of insulin were added to the medium.[3H]-TdR and [3H]-Urd incorporation experiments showed that the inhibition of RNA synthesis of this factor occurred prior to the inhibition of the scheduled DNA synthesis. It is suggested that the mechanism of this lymphocyte chalone actions is likely to inhibit the activation process of some genes, then inhibit the DNA synthesis and block the cells from G1 phase to S phase.

Objective:To investigate the inhibitory effects of Sedum Sarmentosum total flavonoids ( SSTF) on hepatic fibrosis in-duced by CCl4 ,and examine the effects on the expression of TGF-β1 and Smad7. Methods:Sixty male SD rats were randomly divided into the normal control group, the model group, 100, 200 and 400 mg·kg-1 SSTF groups and colchicine positive control group. The experimental model of hepatic fibrosis in rats was established by the injection of CCL4 . The liver histopathology was examined by Mas-son stain, and the protein expression and mRNA of TGF-β 1 and Smad7 were assessed by RT-PCR and Western blotting. Results:Compared with the model group, every SSTF group could significantly reduce the degree of liver fibrosis induced by CCL4(P<0. 05). The middle and high dose SSTF gouprs could significantly reduce the protein expression and mRNA of TGF-β1 (P<0. 05), and sig-nificantly increase the protein expression and mRNA of Smad 7 (P<0. 05). Conclusion:SSTF exhibits anti-hepatic fibrosis effects in rats through down-regulating the expression of TGF-β1 and up-regulating the expression of Smad7 in fibrotic liver tissue.

This article is to report an ultratnicro-quantitative method to determine the tissue content of NAD+. The cycling mixture of nitrotetrazolium blue chloride, phenagene methosulfate, lactate and lactic dehydrogenase is used. The procedure of this assay is very simple and easy to perform. It is sensitive enough to detect as little an amount as 1?10-11 mole per ml of NAD+.