BACKGROUND: Whether choosing a suitable biological scaffold compounding with mesenchymal stem cells (MSCs) can construct an ideal tissue-engineering cartilage or not should be researched further.OBJ ECTIVE: To investigate the feasibility of constructing artificial cartilage by using amplified rabbit MSCs which were inoculated on poly-glycolic acid (PGA).DESIGN: Single sample observation.SETTING: Department of Otolaryngology-Head & Neck Surgery, Affiliated Hospital of Sichuan Luzhou Medical College.MATERIALS: The experiment was carried out in the Luzhou Medical College from October 2004 to October 2005. A total of 8 Japanese large ear rabbits, of both genders, clean grade, aged from 2 to 3 months, weighing 1.5-2.0 kg, were fed in normal temperature and humidity. Poly-glycolic acid was provided by Albany Company, USA.METHODS: Rabbit MSCs were separated, obtained and amplified. In addition, poly-glycolic acid was sheared into pieces with the size of 1 cm × 1 cm × 1 cm and embedded with poly-L-lysine. Amplified MSCs were inoculated on the surface of poly-glycolic acid, and then, they were averagely grown on pre-wet scaffold of poly-glycolic acid according to 4 mL/cm3multi-points spreading style and cultured in vitro for 3 weeks. After the operations mentioned above, samples were regarded as the experimental group. Scaffolds of poly-glycolic acid without MSCs were considered as the control group.Samples in both experimental group and control group were transplanted into abdominal cavity of 4 rabbits, respectively,cultured in vivo for 6-12 weeks, taken out and observed generally. Meanwhile, the samples were fixed with 100 g/L neutrality formaldehyde, cut into sections with the thickness of 5 μm, stained with haematine-eosin (HE) and observed their histomorphological characteristics. Moreover, the samples were stained with alcian blue for observation of glycosaminoglycans formation, with toluidine blue for observation of metachromasia matrix formation, and with immunohistochemical staining for detection of type- Ⅱ collagen expression.MAIN OUTCOME MEASURES: Generally observational results of two kinds ofscaffolds at 6 and 12 weeks after transplanting into experimental rabbits, various staining results and expression of type- Ⅱ collagen.RESULTS: A total of 8 experimental rabbits were involved in the final analysis. ① Generally observational results of two kinds of scaffolds at 6 and 12 weeks after transplanting into experimental rabbits: At 6 weeks after transplanting scaffold into abdominal cavity of rabbits, samples in the experimental group were still coated with greater omentum of abdominal cavity. After clearing greater omentum, three samples were light yellow, smooth and moderate quality; meanwhile, their appearances were coincidence with those before transplantation. However, one sample was gray black and soft quality;meanwhile, it was not able to take shape. Twelve weeks later, appearances of samples in the experimental group were still coincidence with those before transplantation. They were gray white, smooth but hard quality. However, samples in the control group were mostly absorbed at 6 and 12 weeks after transplantation, especially, samples were remarkably absorbed at 12 weeks after transplantation. Any tissue like cartilage did not form in both two durations. ② Various staining results and expression of type- Ⅱ collagen at 6 and 12 weeks after transplanting scaffolds into experimental rabbits: Results of HE staining showed that, at 6 weeks after transplantation, structure of cartilage lacuna-like was started form, and PGA scaffold began to be degraded. In contrast, at 12 weeks postoperatively, some cartilage-like tissue were observed in compound, cartilage lacuna-like structure formed obviously; cells arrayed regularly and geminately existed In cartilage lacuna-like atructure; the smaller cell sizes observed at borders and the bigger ones observed at the center;PGA degraded completely. Results of alcian blue staining showed that, at 6 weeks after transplantation, a partial of regions in tissue were light blue; meanwhile, at 12 weeks after transplantation, matrixes in tissue were mostly blue. This suggested that a lot of glycosaminoglycans were formed. Results of toluidine blue staining suggested that, at 6 weeks after transplantation, blue metachromasia matrixes were observed in tissue; meanwhile, at 12 weeks after transplantation, blue metachromasia matrixes were stronger and stronger in tissue. Results of immunohistochemical staining indicated that, at 6 weeks after transplantation, buffy positive granules were observed in plasma and a few of type-Ⅱ collagen expressed in matrix; meanwhile, at 12 weeks after transplantation, powerfully positive expressions were observed in both plasma and matrix. Expression of type- Ⅱ collage showed that, at 6 weeks after transplantation, dark buffy positive granules were observed in plasma and a few of type- Ⅱ collagen mRNA expressed in matrix; meanwhile, at 12 weeks after transplantation, powerfully positive expressions were observed in both plasma and matrix. Samples in the control group were completely absorbed and any tissue-engineering samples did not form.CONCLUSION: Affecting by osteogenic inducer, rabbit MSCs can generate tissue-engineering cartilage after culture in vitro and in vivo.

Objective To observe the effects of total flavone from litchi chinensis sonn (TFL) on the liver function in-cluding p16 protein, pro collagen type 3 (PC3) and pro collagen typeⅠ(PCⅠ) in model rats with liver fibrosis induced by bile duct ligation. Methods Forty rats were randomly divided into four groups:sham operation (SO) group, bile duct liga-tion (BDL) group, TFL group and silibinin (SIL) group. Rats were gavaged with saline (5 mL·kg-1·d-1) in SO and BDL group, rats were gavaged with TFL (200 mL·kg-1·d-1) in TFL group and rats were gavaged with SIL (5 mL·kg-1·d-1) in SIL group for four weeks. The serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin direct (BILD) and bilirubin total (BILT) were detected in four groups. The liver tissues were stained by HE and Masson methods. The ex-pression levels of p16, PC3 and PCⅠin liver tissues were determined by Western blot assay. Results The serum levels of ALT (44.6 IU/L±8.0 IU/L), AST (103.8 IU/L±18.1 IU/L), BILD (0.76 μmol/L±0.28μmol/L) and BILT (1.48μmol/L±0.35μmol/L) were lower in SO group. There was a higher level of ALT in BDL group (147.4 IU/L±86.3 IU/L) than that of TFL group (92.9 IU/L±47.3 IU/L). The serum level of ALT was higher in AST group (362.7 IU/L±106.6 IU/L) than that of TFL group (290.1 IU/L ± 171.7 IU/L) and SIL group (250.2 IU/L ± 54.9 IU/L). The serum level of BILD was lower in BDL group (99.71μmol/L±40.87μmol/L) than that of SIL group (137.01μmol/L±38.86μmol/L). The serum levels of BILD and BILT were significantly lower in TFL group (81.48μmol/L±47.50μmol/L, 106.64μmol/L±61.04μmol/L) than those of SIL group (P<0.05). There were small amount of new bile duct and no obvious cells degeneration, small amount of infiltration of in-flammatory cells and collagen deposition in TFL group. The liver fibrosis improved significantly in TFL group than that of BDL group. There were more new bile duct in hepatic portal area in SIL group than those of TFL group. The expression levels of p16, PC3 and PCⅠwere significantly higher in BDL group than those of TFL group. The expression level of PC3 was significantly lower in BDL group than that of SIL group. The expression level of PCⅠwas significantly higher in BDL group than that of SIL group (P<0.05). There was no significant difference in the expression level of p16 between BDL group and SIL group. The expression levels of PC16 and PC3 were significantly lower in TFL group than those of SIL group (P<0.05). There was no significant difference in the ex-pression level of PCⅠbetween TFL group and SIL group. Conclusion TFL can improve the liver function in model rats with choles-tatic liver fibrosis and reduce liver fibrosis, which may be related with inhibitory effects on the expressions of p 16, PC3 and PCⅠ.

Objective To study the role of autophagy in the curcumin (Cur) enhancing the chemosensitivity of the colorectal cancer LoVo cells to irinotecan (CPT-11). Methods The LoVo cells were separated into 4 groups:the control group,the Cur group,the CPT-11 group and the Mix group.Western blot assay was applied to determine the expression of autophagy-related protein LC3-Ⅱ and P62. LC3-Ⅱ was detected by immunofluorescence method. Transmission electron microscopy was used to detect the autophagosome. CCK-8 assay was applied to detect the cell growth inhibitory rate of LoVo cells ,which were pre-treated with autophagy inhibitor 3-MA before 24-h treatment of Cur and/or CPT-11. Western blot assay was applied to detect the expression of LC3- Ⅱ and P62. Results The mixed treatment significantly increased the expression of LC3-Ⅱwhile decreased P62 expression,compared with the Cur and CPT-11 treatments. The autophagosomes in cells of Mix group were significantly more than those in cells of the Cur and Cpt group. Pre-treatment of 3-MA significantly reduced cell growth rate in the Cur group,the Cpt group and the Mix group. Pre-treatment of 3-MA significantly decreased the expression of LC3-Ⅱ,while increased P62 expression,compared with the Mix group. Conclution Combinations of curcumin and CPT-11 could enhance the chemosensitivity of LoVo cells to CPT-11,which might be related to the activation of autophagy.