Purpose To construct a recombined antitumor peptide and to analyze its bioactivity. Methods Constructing a recombined gene and inserting the pGEX-4T-3 vector. The recombined protein was expressed in E. coli BL21 and purified with Amylose Resin. Then, citrostatin was subjected to the following tests separately: inhibition of endothelial cell proliferation, MTT test of cytotoxicity and inhibition of endothelial cell tube formation on ECMatrix. Results Citrostatin significantly inhibited the proliferation of human endothelial cell ECV304(IC_(50) = 2.28 μmol/L) .It also significantly inhibited the proliferation of human tumor cell 1990 and NCI-H64O(IC_(50) = 9.24,2.74 μmol/L) ,and the inhibitory effect became more marked with the increase of citrostatin concentration. The inhibitory effects of citrostatin on endothelial cell tube formation was also confirmed . Conclusion An antitumor peptide, citrostatin, has been successfully constructed and purified, which showed anti-angiogenesis effect and direct cytotoxic effect on tumor cells.

Objective To compare the effect of different partition of nucleic acid protein complex on the affinity of enriched library in systematic evolution of ligands by exponential enrichment (SELEX). Methods Two protocols were adopted to select the enriched library to transforming growth factor ? receptor Ⅱ(TGF ? RⅡ). Protocol 1: protein was absorbed on the surface of 96 well plate; then, selection was carried out; the binding nucleotide acids were eluted from the supporter directly. Protocol 2: selection was done in solution; nucleotide acid protein complex was captured in nitrocellulose membrane; the binding nucleotide acids were obtained from membrane. Filter biding assay and gel shift assay were performed to detect the affinity of the enriched ssDNA library from different protocols. Results After 4 rounds of selection, the affinity to TGF ? RⅡ was obviously improved in the enriched library from protocol 2 compared with the initial library, while no such improvement was found in the enriched library from protocol 1. Conclusion In the SELEX experiment, the way of selection in solution, then partition of the binding nucleotide acids in filter is easier to enrich the binding fragment from initial ssDNA random library, compared with the way of fixation of target protein to solid supporter, then selection between the solid phase and liquid phase and elution of the binding nucleotide acids from supporter.

Objective To observe the difference of morphology and phagocytosis between alveolar macrophages (AMs) and pulmonary interstitial macrophages (IMs). Methods AMs were collected by lung lavage and IMs by treatment of the lung tissue with DNAse and collagenase. The two cell populations were analyzed with respect to morphology by transmission electron microscopy, and the variation of these macrophages of phagocytosis were tested by malachite green colorimetry. Results There were great differences in morphology between AMs and IMs. The phagocytosis of AMs was much stronger than that of IMs. Conclusion There is functional and morphological heterogeneity between AMs and IMs. IMs should not be regarded as the precursors to AMs.

Objective To study the profiles of decompression sickness(DCS) in various kinds of animals and to find out the target organ of decompression sickness by providing a basic experimental method for establishing animal models.Method Eleven kinds of animals were exposed to different pressures for different times at different compression/decompression rates.They were monitored at the precordial regions with Doppler flow meter for bubble sounds after decompression to normal pressure,to obtain a record about the developing course of the DCS.Pathological examinations of the bulbar conjunctiva were also made. Result Bubble sound of grade IV were recorded at the precordial regions after decompression.Among them,75%~100% incurred DCS with a diverse extent. Animals developed DCS showed vascular spasm,dysfunction and endothelial tumefaction.Conclusion Each of the 11 kinds of animals can serve as a model of DCS and the processes of development of DCS in various animals are similar.Blood vessels are the target organs of decompression sickness.

ObjectiveTo establish a rat model of nerve damage induced by intrathecal(IT) lidocaine.MethodsFifty-five adult male SD rats weighing 200-220 g were randomly divided into 5 groups (n =11 each):group normal control (group C); group dimethyl sulfoxide (DMSO)-the solvent(group D) and groups IT 5％,10％,15％ lidocaine (groups L5.10.15 ).IT catheter was successfully implanted without complication in groups D,L5,L1o,L15.DMSO,5％,10％ and 15％ lidocaine 20 μl were injected IT in groups D,L5,L10,L15 respectively.Motor dysfunction of hindlimb was assessed and scored (0 =normal,2 =complete block) and paw withdrawal threshold to mechanical stimulation (von Frey filaments) (MWT) and paw withdrawal latency to thermal nociceptive stimulus (TWL) were measured before (baseline) and at 1,2,3,4,5,7 d after IT administration in 8 animals in each group.Three animals in each group were sacrificed at 1 d after IT administration.The lumbar segment (L4-5) was removed for microscopic examination.ResultsThere was no significant difference in motor dysfunction score,MWT and TWL among groups C,D and L5.MWT was significantly increased and TWL prolonged at 1 and 2 d after IT administration in group L10,while in group L15 motor dysfunction score was significantly increased at 1,2 d after IT administration and MWT was significantly increased and TWL prolonged at 1,2,3 d after IT administration.There was significant histologic damage to spinal cord in groups L10 and L15.Conclusion Nerve damage can be induced by IT 10％ lidocaine.

Aim To explore the possibility of the multiple epitope DNA vaccines of hepatitis C virus (HCV). Methods A synthetic multiple epitope antigen gene PCX of HCV was cloned into vector pREP9(RSV promoter) and pcDNA3 (CMV promoter) to construct eukaryotic expression vectors pREP9/PCX and pcDNA3/PCX, then they were used to immunize mice and rabbits, the titer of specific humoral and cellular responses were detected and their safety were observed. Results In mice, specific anti-GZ-PCX antibody(IgG) was lower than 1∶ 1 000 and did not persist well. In rabbits, the highest titer of anti-GZ-PCX IgG reached at 1∶ 3 200 and remained for about one month. Delayed type hypersensitivity reactions (DTH)and proliferation response of peripheral lymphocytes were induced by GZ-PCX antigen. Body weights of immunized mice were normal and no obvious toxic reaction was observed. Conclusion The multiple epitope antigen gene of HCV could induce specific immune responses without obvious toxicity and it might be able to serve as an effective HCV vaccine candidate.