Abstract:The human cytomegalovirus (HCMV)glycoprotein 52 kD gene was cloned and the DNA sequence of antigenic domain of this gene was amplified with polymerase chain reaction (PCR) technique. The sequences of oligonucleotide primers are 5'-AAAGAATTCATGAACGTGAAGGAATCG-3'(upstream primer) and 5'-ATAAAGCTTAATTCAGACGTTCTCTTCTTC-3'(downstream primer). The PCR product was purified and digested with EcoR 1, and then inserted into the EcoR Ⅰ digested expression plasmid pBV-220. The cloned gene was expressed under control of the hybrid P_RP_L promoter in E.coli following induction at 42℃ for 2h, 4h and 6h, respectively. The proteins in the lysate of bacteria were analysed by using 12.5% SDS-PAGE. The predicted protein 13kD expressed from the cloned gene in E.coli was observed and harvested. Up analysing the antigenic domain of HCMV glycoprotein 52 kD, a polypeptide in length of 25 amino acids was synthesized, of which sequence is Phe-Asp-Leu-Glu-Glu-Ile-Met- Arg-Glu-Phe-Asn-Ser-Tyr-Lys-Gln-Arg-Val-Lys-Tyr-Val-Glu-Asp-Lys-Val-Val. The expressed protein and synthetic polypeptide were used to immunize rabbits respectively, and two kinds of antisera reacted with the expressed antigen and HCMV AD 169 antigen detected by using ¹²⁵I-labelled protein A. The results of Dot-blot and Western transfer show that the protein expressed from the cloned gene has the same band in size and specificity of antigen as those of the synthetic poly-peptide. By using horse radish peroxidase (HRP) labelled IgG instead of ¹²⁵I-protein A, preliminary result indicated the diagnostic value of the expressed protein and its antiserum for the HCMV infection.

Abstract:In the paper, the action of metal ions on the human serum albumin had been investigated by fluorescence quenching method. The results showed that Cu²⁺, Mn²⁺, Co²⁺, Cr³⁺,Eu³⁺,Ni²⁺ may bind to human serum albumin and that the fluorescence of human serum albumin may be quenched by nonradiative energy transfer. In terms of Förster type dipoledipole nonradiative energy transfer the distance between the Trp-214 and the bound Cu²⁺ in the first copper-binding site was calculated and found to be about 1.20nm.

Abstract:The extraction and purification methods of type Ⅱ collagen from the rat cartilage were established. Kirietics of fibrillogenesis, stability and ultrastructure of fibils of type Ⅱ collagen of cartilage from rats were investigated in vitro in this paper. The results indicated that the tag phase and growth phase were 15 and 120 min respectively, gelatinization rate in growth phase was 0.0060, gelatin reversibility was 13.58%, and collagen fibrils showed typically banding pattern staggered by 64nm, especially for the native fibrils, but the diameters of these fibrils were larger than those in vivo. These data are of importance for studying the formation and regulation mechanism of collagen fibrils in vivo.

Abstract:The kinetic studies of effect of toxoflavine on the action of xanthine oxidase (ECl, 2,3,2) which was extracted from Pseudomona cocovenenans showed that toxoflavin was nonessential activator for the enzyme, and the activation in condition of hypoxanthine as substrate was more marked than xanthine. The activation obeyed the partial activation type. These results provide us a clue for searching toxic mechanism of toxoflavin for human.

Abstract:By morphological and histochemical methods, the authors demonstrated the differentiation of J6-2 leukemic cells induced by exogenous ganglioside GM3, and studied the change of glycosphingolipid and phospholipid composition after differentiation. The results showed that the main ganglioside component was GM3, and no significant changes were seen after differentiation. The neutral GSL component CMH and phospholipid component PC were shown to increase after differentiation, and lyso-PC, sphingomyelin, PI+PS were shown to decrease. This study suggests a new function of ganglioside——regulation of phospholipid metabolism, the mechanism of which remains to be elucidated.

Abstract:We have studied on the relation between the change of serum gastrin and the acute gastric mucosal lesion. Experimental result shows that the acute gastric mucosal lesion is related to the change of serum gastrin. When the acute gastric mucosal lesion of rats was induced by indomethacin, the serum gastrin level was increased obviously. The drug crude riboflavin preparation could decreased the release of serum gastrin caused by indomethacin.