BACKGROUND: In recent years, acel ular human cadaveric dermis has been applied for repairing dermal defects and fil ing soft tissues, but this repair material is expensive and difficult to obtain. OBJECTIVE: To explore the repair effect of tissue-engineered acel ular dermis on wound healing of skin ulcer. METHODS: Sprague-Dawley rats were randomly divided into autologous reticular dermis and acel ular dermis groups. The tissue-engineered acel ular dermis was prepared by hypotonic solution, 2.5 g/L trypsin, 0.5% Triton X-100 and PBS solution, and in the meanwhile, a rat model of skin ulcer was established. Then, autologous skin graft and tissue-engineered acel ular dermis were transplanted into the autologous reticular dermis group and acel ular dermal group, respectively. Subsequently, comparative study about the repair effect and relative mechanism between two groups was performed. RESULTS AND CONCLUSION: The tissue-engineered acel ular dermis showed a white and grainy shape at room temperature. And hematoxylin-eosin staining showed that: the internal structure of tissue-engineered acel ular dermis exhibited a dendritic distribution, and the gap between col agen fiber bundles was relatively large. At 2, 3, 4 and 8 weeks after dermal transplantation, the survival rate of skin graft in the acel ular dermis group was significantly higher than that in the autologous reticular dermis group (P < 0.05). And the wound contraction rate in the acel ular dermis group was significantly higher than that of the autologous reticular dermis group at 3, 4 and 8 weeks after dermal transplantation (P < 0.05). In addition, the average diameter and clearance rate of col agen fibers in the normal skin around wound in the acel ular dermis group were significantly higher than those of autologous reticular dermis group (P < 0.05). To conclude, it is relatively simple to prepare tissue-engineered acel ular dermis under mild conditions, and the prepared tissue-engineered acel ular dermis presents a regular shape. Moreover, this acel ular dermis achieves desired outcomes in repairing dermal defects, which can promote wound healing by reducing the intradermal DNA residual and significantly improving some biomechanical properties in vivo.

BACKGROUND:An appropriate biomaterial can be directly combined with autologous or al ogeneic skin cel s to construct tissue-engineered skin, which can accelerate skin repair after transplantation onto the skin wounds. It is a good idea to solve the deficiency in skin sources. OBJECTIVE:To study the biological characteristics of the complex with bone marrow mesenchymal stem cel s and to investigate the application of this complex in skin defect repair. METHODS:Twenty-eight Sprague-Dawley rats, SPF grade, were randomized into two groups (n=14 per group). By adjustment of temperature, time, pressure and area of NC perm instrument, scald models were made in rats. Rats in the treatment group were given the repair using composite bone marrow mesenchymal stem cel s, while those in the control group were given vaseline gauze repair. Repair effects were compared between two groups. RESULTS AND CONCLUSION:(1) After 72 hours of culture, the composite bone marrow mesenchymal stem cel s smal with round shape distributed dispersedly. After 5 days of culture, the cel s began to stretch and the cel morphology became unstable. After three passages, the cel morphology became stable. The results of antigen identification showed the expression of CD44 and CD29 but the low expression of CD45 and CD34 in bone marrow mesenchymal stem cel s. (2) Twenty-eight days after repair, there was no obvious scar on the wound surface of the treatment group, but a little shrinkage and obvious scar stil existed in the control group. Moreover, in the control group, the epidermal layer of the skin was relatively thick, and the connection between the basal layer and the dermis was unsatisfactory. In the treatment group, obvious epidermal cel stratification, neat arrangement, and tight connection between the epidermis and dermis were observed. In summary, bone marrow mesenchymal stem cel s are a special class of cel s that have pluripotent ability and are more readily available. These cel s are the preferred target cel s for skin defect repair to promote early healing of the skin and improve blood circulation defect site, which are confirmed to have high clinical value.

Objective To establish osteosarcoma vaccine by the LM9 osteosarcoma derived from C3h mice hybridized with activated B lymphocytes and study its biological behavior and the antitumor efficacy. Methods The LM9 osteosarcoma derived from C3h mice was fused with LPS activated B lymphocytes by using 50%PEG. The fused cells was selected by HAT medium and cultured in vitro, and the biocharacter and efficacy of the fusion vaccine were investigated. Results In contrast to LM8, the fused cells grew significantly slowly in vitro. All the mice under the protection of fused vaccine survived without tumor (8/8), while all the mice in the control group succumbed to the tumor with no survival (8/8), 75%of the mice inoculated subcutaneously with cell fusion vaccine survived without tumor burden after implantation of LM8 cells subcutaneously. The mice in the control group developed tumors and died within 45 days without any exception. Conclusion It is possible that the LM9 osteosarcoma biology characteristics change after fused with LPS activated B lymphocytes. Cell fusion osteosarcoma vaccine could produce prophylactic and therapeutic effects in mice.

[Objective]To prepare a new porous composite artificial bone substitute and evaluate its properties.[Method]Thermally induced phase separation was adopted to prepare the artificial bone made from oyster shell powder and PLLA which were proportionally mixed and its properties as porosity rate,pore size and mechanical strength were assessed.Meanwhile the related variation parameters were examined every 2 weeks in a course of 14 weeks after the slices of CAB and pure PLLA were immersed in NS of 37℃ in vitro,the results of which were compared in statistics.[Result]The average porosity rate of artifical bone with TIPS method was 85.1% and pore sizes ranged 100-300 ?m under the SEM,with better pore connectivity and regulation shape.The average compressive strength was 2.12 MPa.As the immersion prolonged,the regular variation was observed about the mass loss of CAB and the pH alteration of solution,there was statistically difference in the indexes between the two groups(P﹤0.05).[Conclusion]The porosity rate,pore size,mechanical strength and degradation performance in vitro of the artifical bone made by TIPS method can satisfy the requirement of bone substitute.

Objective To investigate clinical outcomes and side effects of 103Pd seed brachytherapy for malignant tumors. Methods Twenty patients with residual or recurrent unresectable malignancies were treated with 103Pd seed implantation under the guidance of ultrasonigraphy or CT scans. Three patients were given a local anesthesia and 17 patients, general anesthesia. The match peripheral doses ranged from 97.3 Gy to 182.78 Gy (mean, 123 Gy). The activity of each seed ranged from 1.4 mCi to 1.8 mCi. The planning target volume (PTV) included a 1 cm isotropic expansion margin around the clinical target volume (CTV). The seeds were retrogradely placed with a Mick applicator. External beam radiation was required 3～4 weeks after seed implantation in 6 patients, with a total dose of 45～50 Gy and 2 Gy each fraction. All of the patients received CT scanning after implantation for quality evaluation and underwent routine chest X-ray examination at 24～48 hours for seed observation. Results A complete response was achieved in 5 patients and a partial response in 12 patients. Two patients were assessed as having stable disease. In 1 patient with prostatic cancer, the serum PSA level was decreased significantly. The local control rate was 90% (18/20). The 20 patients were followed for 2～25 months (median,11 months).Two patients were lost to follow-up at 6 and 12 months after operation, respectively. Twelve patients died and 6 patients survived.No severe complications were recorded postoperatively. Conclusions 103Pd brachytherapy for malignant tumors gives a high local control rate and satisfactory reliability.

To establish a xenografted tumor strain of human osteosarcoma in nude mice and a homologous cell line, the osteosarcoma speciments from patients were inoculated into the subcutaneous tissue of nude mice. After the transplanted tumor had grown to about 2cm in diameter, the tumor tissue was cultured in vitro and the continuously growing cells were analyzed by morphology, histochemistry, immunohistochemical straining, cell cycling analysis ,chromosome analysis and heterotransplantation. A newly established cell line designated PL 1 was thus obtained in this laboratory in continuous culture for over 100 passages. Under light and electron microscopes, the cells assumed the main characters of malignancy.Morphological observation, histochemistry analysis and BMP immunohisto chemical straining showed that they had the features of osteosarcoma.The cell cycle analysis showed 53 2% of the cells were in G 1. This cell line could produce ALP and BMP.Chromosome analysis confirmed that they had retained a karyotype of human cancer cells and a hypotriploid feature with a mode number of around 64～66.The tumor formation rate after heterotransplantation was 100%. It had lung metastasis characters. Therefore, PL 1 cell line derived from the xenograft in nude mice has been established and maintained for over 9 months trough 100 passages, and this cell line can provide material and model for further investigation of human osteosarcoma.

Objective: To prepare surface with collagen, so as to increase the histocompatibility of deantigenic bovine cancellous bone. Methods: Bovine cancellous bone was degreased and macerated by H 2O 2 and decalcified with 0.3 mol/L HCl to form scaffold, surface of which was treaed with collagen, then cultured rabbit osteoblasts were seeded into the scaffold and cultured in vitro . 4, 10, and 21 days later, the cells on the composite materials were observed under sanning election microscope. Results: On day 4, the cells grew in the surface of the scaffold; on day 21, the cells grow into the pores and on all of the surace of the scaffold.Conclusion: Deantigenic bovine cancellous bone with surfaces treated by collagen is histocompatable with rabbit osteoblasts.

BACKGROUND: Bone defect repair is a difficulty in orthopedic field all the time, researches on the tissue engineered bone tissue have provided completely new thoughts and methods for bone defect repair, and it is an important link to detect the biocompatibility of the biomaterials.OBJECTIVE: To investigate the biocompatibility of PCL with bone marrow stromal cells (BMSCs).DESIGN: A controlled observation.SETTING: Department of Orthopaedics, the First Affiliated Hospital of Xinjiang Medical University.MATERIALS: The experiments were carried out in the orthopedic laboratory of the First Affiliated Hospital of Xinjiang Medical University. Healthy 4 to 8-week-old New Zealand rabbits of about 2 kg were used.METHODS: ① Bone marrow was extracted from bilateral femurs of the rabbits, then mixed into 10 mL RPMI1640 complete medium, and then entered the passage culture. ② The cells were inoculated and then divided into PCL group and control group, the cells were only inoculated in the control group, and the BMSCs were co-cultured with PCL in vitro in the PCL group. The morphological observed, cell proliferation, protein content and enzymological determinations were conducted.MAIN OUTCOME MEASURES: The growth and the adhesion of BMSCs on PCL biomaterials were mainly observed.RESULTS: In the control group, most of the BMSCs changed to the shape of fusiform or multi-angles. In the PCL group, the BMSCs could adhere and proliferate on PCL, and the growth and function were not affected, PCL also played a certain role in promoting the cell proliferation.CONCLUSION: PCL possess satisfactory biocompatibility, and it is possible to be used as the carrier of BMSCs in tissue engineering.

Objective:To compare the effect of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on the abdominal visceral fat of obese women.Methods:Sixty-eight obese female college students were randomly divided into an HIIT group ( n=23), an MICT group ( n=22) and a control group ( n=23). The control group was not given any training intervention. The MICT group performed continuous exercise at an intensity of 60% of each person′s maximum oxygen uptake (VO 2max) until 300kJ of work had been performed. Those in the HIIT group performed repeated 4-minute bouts of cycling at 90% of their VO 2max with 3-minute intervals until 300kJ of work had been performed. The interventions lasted 12 weeks. The subjects′ visceral fat (AVFA) and abdominal subcutaneous fat (ASFA) were measured using computed tomography. Whole-body fat mass (FM) and FM in the android, gynoid and trunk regions were detected using dual energy X-ray absorptiometry before and 48 hours after the final session. Results:After the intervention, the average AVFA, ASFA, percentage of fat mass (FM%), whole-body FM, and FM in the abdominal, gluteo-femoral and trunk regions of the HIIT group and MICT group were significantly lower than before the intervention, but there was no significant difference between them. No significant differences were observed in any of the control group′s indexes.Conclusions:Both HIIT and MICT can reduce the abdominal visceral fat of obese female college students, and the effects of the two exercise modes are equivalent.

A special method of clinical tumor radiation therapy,namely 3DCRT& IMRT,is described in this paper,including its design and clinical application.