Objective:To investigate the relationship between the Notch signaling pathway and expression of vascular relevant factors in rabbit deep Ⅱ degree burn model.Methods:A total of 120 New Zealand white rabbits were randomly divided into a block group,a model group,and a control group,The block group was injected 2 mg/kg γ-secretase inhibitor (GSI) once a day at 1 d before the model establishment,and 1-14 d after the deep Ⅱ degree burns model establishment.The model group were injected physiological saline at the same time.The control group was only injected with the same amount of saline.The expressions of vascular endothelial growth factor (VEGF),vascular endothelial growth factor receptor 2 (VEGFR-2),matrix metalloprotein 2 (MMP-2) and matrix metalloprotein 9 (MMP-9) were detected by immunohistochemistry.Results:The expressions of VEGF and VEGFR-2 in the model group and the block group were significantly increased within 21 days after modeling,while decreased after 21 days;the expressions of MMP-2 and MMP-9 were decreased within 21 days after modeling,while increased after 21 days,with significant differences compared with the control group (P＜0.05).The expressions of VEGF and VEGFR-2 in the model group were higher than that in the block group,and the expressions of MMP-2 and MMP-9 were lower than those in the block group (P＜0.05).The expression of VEGFR-2 was positively correlated with VEGF,while MMP-2 and MMP-9 were negatively correlated with VEGF within 21 days after modeling.Conclusion:In the rabbit deep Ⅱ degree burn model,the Notch signaling pathway was blocked to attenuate the expressions of VEGF and VEGFR-2,and to up-regulate the expressions of MMP-2 and MMP-9.

BACKGROUND: The development of cartilage tissue engineering provides novel ideas for treatment of articular cartilage defects and implements construction of tissue-engineered cartilage in vivo.OBJECTIVE: To investigate the feasibility of constructing tissue-engineered osteochondral composite through bone marrow stem cells(BMSCs) cultured on the poly(lactide-co-glycolic acid) (PLGA), which was modified with collagen and cellular growth factors.METHODS: PLGA was made by phase separation technique, composited with collagen Ⅱ, basic fibroblast growth factor, and transforming growth factor-β1. The BMSCs of passage 3 were cultured on the above scaffolds. Thirty-six SD rats were randomly divided into experimental, control, and blank groups. These three groups received implantation of BMSCs composited with growth factors and collagen-PLGA, implantation of BMSCs composited with collagen-PLGA, and implantation of collagen-PLGA into the muscle, respectively. At 4, 8, and 12 weeks after surgery, cell directional differentiation and growth were examined by gross observation, hematoxylin-eosin staining, toluidine blue staining, collagen Ⅱ staining, and scanning electron microscope.RESULTS AND CONCLUSION: Gross observation showed that there were many chondroid tissues in the experimental group and fibrous tissues in the control and black groups. Stainings and electron microscope revealed that many chondroblasts and a few osteoclasts appeared in the composite of the experimental group. Toluidine blue and collagen Ⅱ stainings were positive in the experimental group and negative in the control and blank groups. These findings demonstrate that PLGA modified with collagen had a good cellular compatibility. BMSCs cultured on PLGA, which was modified with collagen and cellular growth factors, can construct the tissue-angineered osteochondral composite in rats.

Objective\ To observe the practicality of sonography for differentiating the compression factors and judging whether thorough decompression anterior to the dura sac has been obtained. Methods Posterior midline incision was used in a total of 16 cases. After the laminae were resected, normal saline was poured into the operation field, and ultrasound examination performed with a 5.0 MHz sectorscanner. Combined with preoperative imaging (CT or MRI),the compression factors were differentiated. The isolated tissue(bone or disc)pieces in spinal canal were removed first,then reduction of approximate and distal parts of the injuried spinal column was obtained with the help of the Dick devices. Posteriorly protruded bone mass was tumbled in carefully supervised with sonography. The sonographic criterion for thorough decompression consisted of the reappearance of the anterior subarachnoid and an even and smooth echo of posterior dura mater. Results\ The sonographic criterion for thorough decompression was achieved in all cases. No bone mass posterior displacement was observed on postoperative rontgenogram or CT examination. Partial or complete recovery of neural function was obtained in 13 cases. Conclusion\ All elements contributing to anterior dura sac compression can be readily recognized by sonography,which offers a reliable criterion for complete decompression.

Objective To evaluate the effect of left gastric venous caval shunt in the treatment of portal hypertension. Methods Eight patients suffering from portal hypertension underwent left gastric venouscaval shunt. The graft was of autogenous vein in 5 cases and artificial vein in 3 cases. Results There was no mortality and major complication nor early rebleeding. All patients were followed up from 10 mos to 10 years with an average of 5 years and 2 mos.Postoperatively,5 cases retrieved active living style. Two cases died, and one was lost during the follow-up. Conclusion Left gastric venous caval shunt decreasesthe venous pressure of the portal system within pericardiac and lower esophageal area. The shunt is a safe and effective surgical treatment presenting less alterations to splanchnic hemodynamics and with an additionaladvantage for pericardial devascularization.