BACKGROUND:It is particularly important to search favorable scaffolds and seed cells in bone tissue engineering. However, no existing studies have reported the co-culture of adipose-derived stem cells and absorbable gelatin sponge.
OBJECTIVE:To induce rabbit adipose-derived stem cells to osteoblasts, observe the adhesion, proliferation and biological characteristics of adipose-derived stem cells on absorbable gelatin sponge, and to provide experimental base for absorbable gelatin sponge as an effective carrier of fat stem cells transplantation in vivo.
METHODS:Adipose-derived stem cells were cultured in vitro and identified with immunohistochemistry and flow cytometry. The passage 3 adipose-derived stem cells were induced to differentiate into osteoblasts and then seeded onto absorbable gelatin sponge after treatment with polylysine. The adhesion and proliferation of adipose-derived stem cells on scaffolds were observed under scanning electron microscope.
RESULTS AND CONCLUSION:The rabbit adipose-derived stem cells were mainly round and oval shaped at 48 hours, and became long spindle shaped after 48 hours. Adipose-derived stem cells were positive for CD29 and CD44, and negative for CD33 and CD34. Adipose-derived stem cells can be induced to differentiate into osteoblasts after culture in the osteogenesis induced fluid for 72 hours. The induced osteoblasts that were co-cultured with absorbable gelatin sponge had an 85%adherence rate at 24 hours. The cells began to extend pseudopodium at 48 hours, and osteoblasts adhered in clumps and secreted a large amount of cellmatrix at 7 days. Absorbable gelatin sponge began to absorb and degrade. Experimental findings indicate that, adipose-derived stem cells have good histocompatibility with absorbable gelatin sponge, and absorbable gelatin sponge can be used as a biological carrier of adipose-derived stem cells.

The treatment of avascular necrosis of the femoral head whose pathological procedure is femoral head avascularity and osteocyte necrosis induced by many etiological factors is one of the difficult subjects in orthopaedics. As a newly-developed technology, cytokines and gene therapy have been widely used in the research of avascular necrosis of the femoral head. Many cytokines and transduced genes have the effects of promoting vascular reconstruction and bone repairment so that it could recover the blood supply and repair the osteonecrosis of femoral heads. Most current researches remain in the experimental phase. Therefore, the research focus in the future comes down to the lengthening of gene transfection expression as well as the selection of vectors and tissue engineering bones that have low immunereaction and low toxicity.

ObjectiveTo study the effects of angiogenesis inhibitor SU6668 on the growth and metastasis of colon cancer in vivo. MethodsMetastatic model of human colon cancer was established by orthotopic implantation of human tumor tissue into colon wall of nude mice. Mice were randomly divided into control, 5 Fu, SU6668, and combined treatment group (both 5 Fu and SU6668 i.p.) respectively. After six weeks tumor weight, inhibition rates, intratumoral microvessel density (MVD), apoptotic index (AI) and metastasis were evaluated. ResultsCompared with control, tumor growth was significantly inhibited in mice treated respectively with 5 Fu, SU6668 and 5Fu plus SU 6668 with an inhibition rate of 0%, 42 6%, 80 9% and 87 2% respectively. MVD decreased significantly in treated groups \[(13 8?5 2)?(12 3?4 5), (2 4?1 5) and (0 9?0 5)\]. AI increased significantly in treated groups \[(3 6?2 4)%? (7 1?5 7)%, (11 9?3 9)% and (19 9?8 6)%\]. The incidences of peritoneal and liver metastases was significantly inhibited in 5 Fu, SU6668 and combined treatment group (100%? 45 5%, 16 7% and 0; 75 0%? 36 4%, 16 7% and 0). The growth and metastasis of human colon cancer implanted in nude mice were significantly inhibited in the SU6668 group and combined group than that in control group and 5 Fu group ( P

Objective To establish an orthotopic implantation and metastasis model of human colon cancer in nude mice. Methods Tumor cell line SW1116 of human colon adenocarcinoma was inoculated subcutaneously into nude mice to develop implantation tumor.Histologically intact tumor tissue was then harvested and implanted to the colon wall of nude mice to set up a model similar to human colon cancer.The formation of implanted tumor rate, local tumor growth characteristics,and metastasis rates were examined. Results A 100% lymphatic metastasis rate was obtained in this model. The incidences of local lymphatic metastasis, peritoneal and liver metastases were 100%, 91.7% and 75.0% respectively.Emacication and exhaustion of the nude mice were presented in late stage of the experimentation. The median survival time of the tumor-bearing nude mice was 10 weeks. Conclusions The orthotopic implantation tumor and metastasis model provide useful tools for the study of mechanism of metastasis and its treatment of human colon cancer.

Objective: To study the inhibition effects of thalidomide on the growth and metastasis of gastric cancer in vivo in nude mice. Methods: Metastatic model simulating human gastric cancer was established by orthotopic implantation of histologically intact human tumor tissue into gastric wall of nude mice. Mice were randomly divided into 4 groups: control group (saline solution 0.5 ml, ip), 5 FU group (fluorouracil 30 mg?kg -1 ?d -1 , ip), thalidomide group (thalidomide 250 mg?kg -1 ?d -1 ,ip), combined treatment group (both 5 FU and thalidomide, ip). Six weeks after implantation, the tumor weight, inhibition rates, intratumoral microvessel density (MVD), apoptotic index (AI) and the metastasis were evaluated after the mice were sacrificed. Results: Compared with the control group, growth of tumor was significantly reduced in mice treated with 5 FU, thalidomide and combined treatment (inhibition rate 39.8%, 48.1% and 74.1%). The incidences of liver metastases was also significantly inhibited in the 5 FU group, thalidomide group and combined treatment group than in control group(8/11 vs 4/12, 3/12 and 0/12). The incidences of peritoneal metastases was also significantly inhibited in the 5 FU group, thalidomide group and combined treatment group than in control group(7/11 vs 3/12, 3/12 and 0/12). The MVD decreased significantly in thalidomide group and combined treatment group. AI increased significantly in the treated mice. Conclusion: Thalidomide can induce apoptosis in gastric cancer by inhibiting tumor angiogenesis and has inhibitory effect on growth and metastasis of human gastric cancer implanted in nude mice. Combination of thalidomide with cytotoxic agents is more effective.

Objective To study the effects of angiogenesis inhibitor SU5416 on the growth and metastasis to the liver of gastric cancer and to investigate its effect on the apoptosis of gastric cancer cells. Methods Metastatic model simulating human gastric cancer was established by orthotopic implantation of histologically intact human tumor tissue into gastric wall of nude mice. Mice were randomly divided into 4 groups: control group (saline solution), 5 FU group (fluorouracil 30 mg?kg -1 ?d -1 i.p.), SU5416 group (SU5416 15 mg?kg -1 ?d -1 i.p.), and combined treatment of both 5 FU and SU5416 group. Eight weeks after implantation, the tumor weight, inhibition rates, intratumoral microvessel density (MVD), apoptotic index (AI), and the presence of metastasis were evaluated respectively after the mice were sacrificed. Results Compared with the control group, the growth of the orthotopically implanted tumor was significantly inhibited due to the reduced weight and the inhibition rate of tumor was 44.5%, 79.3%, and 84.4% respectively in mice treated with 5 FU, SU5416 and both. The incidences of liver metastases were also significantly decreased in the 5 FU group, SU5416 group, and combined group compared with those in control group (36.4%, 25.0%, and 0% vs 90.0%). The MVD was decreased significantly in the treated mice ( 14.6 ? 5.8 vs 13.1?4.7, 3.9? 1.8 , and 2.1?1.5). The AI was increased significantly in the treated mice [(3.76?2.25)% vs (6.81? 4.92 )%, (9.82?3.76)% and (17.65?9.85)%]. The growth and liver metastasis of human gastric cancer implanted in nude mice were more significantly inhibited in the SU5416 group and combined group than in control group and 5 FU group ( P

BACKGROUND: Hormone use has become the primary cause of steroid-induced avascular necrosis of femoral head (SANFH). OBJECTIVE: This study used a combination of injection of horse serum and a large dose of corticosteroid to develop a hormone-induced rabbit model of early avascular necrosis of femoral head (ANFH), and preliminary discussed the pathogenesis of ANFH. METHODS: New Zealand rabbits were randomly divided into three groups. Methylprednisolone with horse serum group: horse serum (10 mL/kg) was injected. Three weeks later, 6 mL/kg of horse serum was injected. Two weeks later, 45 mg/kg of methylprednisolone was daily injected for 5 consecutive days. Methylprednisolone group: 45 mg/kg of methylprednisolone was daily injected for 5 consecutive days. Control group: no treatment was given. Serum cholesterol and triacylglycerol levels were detected at 1, 3, 7 and 14 days before and after hormone injection. MRI and histopathological detection was done in femoral head at 2, 4 and 8 weeks after hormone injection. RESULTS AND CONCLUSION: The serum triglyceride and total cholesterol in methylprednisolone with horse serum group and methylprednisolone group were higher than control group at 1 and 3 days after hormone injection (P < 0.01). MRI results displayed abnormal signal in femoral head at 4 weeks in methylprednisolone with horse serum group, but in the methylprednisolone group at 8 weeks. Histological detection results exhibited that at 4 weeks, some trabeculae were broken into fragments, and the empty bone lacunae increased. At 8 weeks, the trabeculae showed thinning and broken. There were large amount of empty bone lacunae with bone cell atrophy and larger fat cells which were fused into bubbles. In methylprednisolone group, the level of necrosis was lighter than methylprednisolone with horse serum group during each period. Results suggest that hormone combined with horse serum can successfully prepare early-stage hormone-induced ANFH.

BACKGROUND: Traditional methods of repairing bone defect such as autograft and allograft have some disadvantages that are hard to deal with, gene treatment may be a new approach. OBJECTIVE: To investigate the biological properties of cultured human osteoblasts transfected with vascular endothelial growth factor (VEGF) gene. DESIGN, TIME AND SETTING: A controlled experiment based on cytology was carried out in the Scientific Experiment Centre of Liaoning Medical College from May 2005 to May 2006. MATERIALS: Human lilac born block was harvested from a cervical spondylosis patient who required lilac bone graft with his informed consent of this patient. Plasmid pCDI/VEGF_(121) was given as gift from Professor Ma, Peking Unviersity Human Disease Genomics Research Center. Competent Escherichia coU was given as gift from Professor Liu, Liaoning Medical College. METHODS: Human osteoblasts were isolated and cultured in vitro. There were a VEGF transfection group and a control group in the experiement. Using cation liposome, the pCDINEGF_(121) eukaryotic expression plasmis was induced into human osteoblasts.MAIN OUTCOME MEASURES: At 1, 3, 5, 7 days following passage culture, the expression of VEGF in human osteoblasts was detected. Its effects on the call proliferation, the secretion of osteocalcin and alkaline phosphatase were investigated.RESULTS: After the plasmid pCDI-VEGF_(121) was transferred into human osteoblasts 3 and 7 days, VEGF mRNA expression was detectable by RT-CPR method. The call number of transfection group was larger than that of control group (P < 0.05 or P < 0.01).When the cells were cultured for 3 days, the positive rate of alkaline phosphatase in the transfection group was increased compared with control group (P < 0.01 ); the secretion of osteocalcin in the transfection group was higher than that of control group (P < 0.05 or P < 0.01 ).CONCLUSION: VEGF gene transfection can improve the proliferation and biological function of human osteoblasts cultured in vitro.

BACKGROUND:At present, dexamethasone has been widely used in the perioperative period of major surgery in the orthopedics for reducing postoperative pain and nausea and vomiting, but the study on the application of methylprednisolone to reducing postoperative nausea and vomiting and pain after unilateral total knee arthroplasty is rarely reported.OBJECTIVE:To evaluate the effects and safety assessment of the application of methylprednisolone on postoperative nausea and vomiting and pain after unilateral total knee arthroplasty. METHODS:A total of 86 patients undergoing unilateral total knee arthroplasty were randomly assigned to two groups. Patients in the methylprednisolone group were given methylprednisolone 40 mg in intravenous drip within 24 hours during and after replacement. Patients in the control group were given an equal volume of saline in intravenous drip at the same time. The incidence of postoperative nausea and vomiting was observed and recorded at 0-6 hours, 6-24 hours, 24-48 hours, and 48-72 hours after surgery, as wel as the total incidence was recorded in both groups. Pain visual analogue scale (VAS) score at 6, 24, 48 and 72 hours after replacement, and knee joint scoring system (KSS) score at 3 days after replacement were recorded. C-reactive protein and fasting blood glucose were determined. The occurrence of adverse reactions postoperatively was recorded in 6-month fol ow-up in both groups. RESULTS AND CONCLUSION:(1) The total incidence rate of postoperative nausea and vomiting during 0-72 hours after surgery, and incidence rates of nausea and vomiting at 6 and 24 hours were significantly lower in the methylprednisolone group than in the control group (P<0.05). (2) Pain VAS score was significantly lower in the methylprednisolone group than in the control group at 6 and 24 hours after surgery (P<0.05). (3) KSS scores were significantly higher in the methylprednisolone group than in the control group after surgery (P<0.05). (4) C-reactive protein and fasting blood glucose were not significantly different between two groups before and after surgery (P>0.05). (5) The surgical incision was found to heal in 3-month fol ow-up and no postoperative infection occurred in both groups. (6) Results show that methylprednisolone can obviously reduce postoperative nausea and vomiting and pain in unilateral total knee arthroplasty, and did not increase the incidence of postoperative infection.

Objective To evaluate the feasibility of interstitial implantation of ~(125)I seeds for malignant tumor at the Head and Neck. Methods From Oct 2006 to Oct 2008,26 patients received interstitial implantation of ~(125)I seeds in our hospital because of recurrent or metastatic malignant tumors at the head or neck after surgery or chemotherapy. ~(125)I seeds were implanted into the tumor tissues under guidance of CT. Results The operation was completed in all the patients. A median of 23 seeds (12～54) were implanted in each case. No complications, such as hemorrhage, infection, or seed migration, occurred in the patients. The patients were followed up for 3～24 months. During the period,the rate of local control was 54% (15/28) at 3 months,72% (18/25)at 6 months,47% (11/23)at 12 months,and 37% (6/16)at 2 years. Conclusion Interstitial implantation of '2!I seeds is feasible for ecurrent or metastatic tumor at the head or neck with a good short - term outcome.