Objective To observe the biological characters of chondrocytes in articular loose body and to find out seeding cells for cartilage tissue engineering. Methods Samples from 5 loose body cartilages, 2 normal articular cartilages and 6 osteoarthritis articular cartilages were collected. Part of each sample’s cartilage was histologically studied to observe the chondrocytes distribution the morphologic changes by toluidine-blue staining, chondrocytes’ apoptosis by terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate-biotin nick end-labeling (TUNEL). The rest of each cartilage was digested and isolated by 0.25% trypsin and 0.2% collagenase Ⅱ, and then were cultivated in 10%DMEM. Their morphologic changes were observed 24h later.Comparison was made btween three cartilages. Results Compared with normal cartilage and osteoarthritis articular cartilage, the cells density was higher, their lacunars were larger, cells distribution was irregular, and apoptosis was more apparent in loose body cartilage. Conclusion The characters of chondrocytes from loose body is more like fibroblasts so they can not serve as seeding cells directly for cartilage tissue engineering.
Objective To investigate the influence of vascular endothelial growth factor (VEGF) antagonist bevacizumab on the growth of human choroidal melanoma (CM) OCM-1 cell xenografts in nude mice, and to explore the probable mechanism.Methods OCM-1 cells were subcutaneously implanted on 18 nude mice to establish ectopic model of human CM. The nude mice with the tumor of 5 mm in diameter were randomly divided into three groups: untreated group (group A), normal saline （NS） group (group B), drug treated group (group C). Bevacizumab was intraperitoneally injected for 14 consecutive days in group C, and the same volume of NS was used at a same way in group B. The volume and weight of implanted tumor as well as inhibitory rates of drug on tumor were calculated, ki67 and survivin proteins were measured with immunohistochemistry, and the mRNA expression of VEGF and survivin were assessed by RT-PCR.Results The volume and weight of tumor was (598.86plusmn;321.81) mm3, (0.66plusmn;0.15) g; (1 715.15plusmn;278.16) mm3, (1.54plusmn;0.39) g and (1 750.23plusmn;206.36) mm3, (1.54plusmn;0.31) g in groups C, A and B, respectively. There were significant differences between group C and A (F=34.53, P=0.00) and group C and group B (F=8.69, P=0.01). The inhibitory rate of these three groups were 57.14%, 5.31%, 6.25%, respectively, and the proliferation index (PI) of ki67 in these three groups were (51.85plusmn;1.32)%, (46.30plusmn;1.39)%, (27.90plusmn;0.90)%, respectively, there were significant differences in ki67 PI between C group and A or B group (H=15.17, P=0.00). The expression of survivin mRNA was (0.49plusmn;0.02), (0.82plusmn;0.05) and (0.61plusmn;0.05) in groupss C, A and B, respectively, there were significant differences between C group and A or B group (F=15.17, P＜0.05) . The expression of VEGF mRNA was (0.32plusmn;0.08), (0.73plusmn;0.07), (0.80plusmn;0.04) in groups C, A and B, significant difference was found between group C and A or B group (F=12.05，P＜0.05). Conclusion Bevacizumab can inhibit the growth of human CM in nude mice probably by inhibiting the activity of VEGF and downregulating survivin expression of the tumor as well as inhibiting the growth of the tumor.