BACKGROUND:As a bone reconstruction material, nano-hydroxyapatite has good biocompatibility and osteoconduction, but the clinical use of nano-hydroxyapatite alone stil has many deficiencies. OBJECTIVE:To explore the in vivo osteogenic capability of nano-hydroxyapatite/ polyamide composites. METHODS: Twenty-four New Zealand white rabbits were subjected to humeral head replacement using nano-hydroxyapatite/polyamide composite material. X-ray observation and histological observation were done at 3, 6, 12, 24 weeks after replacement. RESULTS AND CONCLUSION: (1) X-ray observation: No thinned cortical bone and ectopic ossification occurred on the upper end of the composite material at different time, and the nano-hydroxyapatite/polyamide material had no signs of fragmentation. The cortical bone around the composite material was fuzzy, and the bone mineral density was increased with time. (2) Histological observation: At 3 weeks after replacement, a large number of cels could be visible, including mesenchymal stem cels and mononuclear macrophages. At 6 weeks after replacement, a large amount of fibrous tissues, fibroblasts and mononuclear macrophages stil existed in the boundary membrane, but chondrocytes and osteoblasts distributed less. At 12 weeks after replacement, a wide range of original trabecular bone began to form and were mostly flat that arranged regularly. At 24 weeks after replacement, the boundary membrane was ful of bone cels, but the cels on the surface of trabecular bone were relatively regular and primitive cels in the bone tissue began to transform into the lamelar bone. These findings indicate that the nano-hydroxyapatite/polyamide material has good osteogenic capability.

Objective:To investigate the value and molecular mechanism of gastric cancer stem cells in invasion and metastasis of gastric cancer.Methods:Gastric cancer stem cells were isolated by spheroid culture method, and the biological characteristics were identified. The role of gastric cancer stem cells in multidrug resistance, invasion and metastasis was analyzed. The important molecules involved in the biological behavior of gastric cancer stem cells were identified by gene chip. Screening of the signaling pathway revealed that anthrax toxin receptor 2 (ANTXR2)plays an important role in invasion, metastasis, glomerization and tumor formation.Results:Sox2 and Bmi1 expression in SGC7901 and MGC803 cells were significantly higher than monolayer culture cells (15.39±3.23). Oct4 express increased to (4.19±0.62). The expression levels of the dry-related genes Bmi1, Sox2 and Oct4 in SGC7901-SC cells were (3.29±0.52), (3.12±0.49), (2.58±0.35), respectively, which were higher than those of SGC7901-MN cells, Bmi1, Sox2 and Oct4, respectively. The differences were statistically significant ( t=5.392, 7.316, 6.449, all P<0.05) for (1.41±0.39), (2.04±0.33), (1.39±0.32); in primary cells XN0422-SC and in SGC7901-SC cells, miR-638 was in high expression (0.69±0.11), and miR-181b and miR-181a in low expression (0.12±0.05) and (0.15±0.07). ANTXR2 expression in SGC7901-SC cells was higher than that in SGC7901-MN cells ( t=6.216, P<0.05). The ANTXR2 positive cells in SGC7901-SC was 85.48%. The proportion of ANTXR2 positive cells in SGC7901 was 4.98%. Gastric cancer cells XN0422 and SGC7901 were affected by PLVT713, and ANTXR2 expression protein decreased. Conclusion:ANTXR effects a regulatory role by activating the Src/ERk signaling pathway, which can be used to predict the biological beharious of gastric cancer.

Objective:To study the effect of extract of livistona chinensis on the proliferation and apoptosis of bladder cancer cells and the related mechanism.Methods:T24 cells were cultured in medium with the final concentration of 0, 25, 50 and 100 mg/L livistona chinensis extract, respectively. And then they were divided into control group and low, medium and high dose groups. The cell survival rate was detected by cell counting kit 8 (CCK-8). Colony formation assay was used to detect the number of cell clones. Apoptosis was detected by flow cytometry. Western blot was used to detect the expression of related proteins. The Syk overexpression vector plasmid and its negative control were transfected into T24 cells. After transfection, the cells were treated with 100 mg/L livistona chinensis. The cell survival rate, colony formation number and apoptosis rate were detected by the above method. The bladder cancer model nude mice were treated with different concentrations of livistona chinensis extract. Under the microscope, the expression of protein was detected by immunohistochemical staining of bladder tissue.Results:Compared with the control group, the survival rate of T24 cells in the low, medium and high dose livistona chinensis extract groups were significantly decreased [(88.50±3.65)%, (70.58±2.47)%, (48.90±2.37)% vs. (98. 25±4.26)%], and the number of clone formation decreased significantly [(101. 33±3.40), (84.00±2.94), (60.00±2.16) vs. (121.33±4.64) ], and the apoptosis rate was significantly increased [(11.45± 0.59)%, (17.71±0.64)%, (21.33±0.83)% vs. (7. 86±0.43)%]. The expression level of Ki-67 protein was significantly decreased, while the expression levels of Caspase3 and Syk protein were significantly increased in a concentration dependent manner ( P < 0.05). The cell survival rate of pcDNA3.1-Syk group was significantly lower than that of pcDNA3.1 group [(63.87±2.53)% vs. (98. 45±3.54)%], the number of clone formation decreased significantly [(74. 33±2.87) vs. (121.33±3.68)], and the apoptosis rate was significantly increased [(18.39±0.63)% vs. (7.89± 0.45)%] (all P<0.05). The cell survival rate in the high-dose group of livistona chinensis+ pcDNA3.1-Syk was significantly lower than that in the high-dose group of livistona chinenisi+ pcDNA3.1 group [ (29.80±1.63)% vs.(49.33±2.76)% ], the number of clone formation decreased significantly [(33.00±2.94) vs. (59.67±3.30) ], and the apoptosis rate was significantly increased [(26.93±0.68)% vs. (21.25±0.78)% ]( P<0.05). The experimental results of nude mice of bladder cancer model showed that the tumor volume of transplanted bladder cancer nude mice in the control group and the low, medium, and high dose livistona chinensis extract groups were (1 209.75±64.37), (1 006.31±40.49), (530.58±42.87), (267.58±16.73)mm 3, respectively, the weight of the transplanted tumor were (0.36±0.08), (0.30±0.04), (0.26±0.03), (0.18±0.06)g, and the differences between the two groups were statistically significant ( P <0.05). Immunohistochemical staining results showed that the expression of Sky and Caspase3 was increased and the expression of Ki-67 was decreased in the middle and high dose groups compared with that in the control group. Conclusion:Extract of livistona chinensis can inhibit the proliferation and promote apoptosis of bladder cancer cells by up regulating Syk expression.