Objective To study the effects of Cad-Ⅱgene on osteogenic differentiation of human mesenchymal stem cells in vitro. Methods The human marrow mesenchymal stem cells (hBMSCs) were isolated and cultured in vitro before they were divided into 2 groups. In the transfeetion group, the hBMSCs were transfeeted with Cad- Ⅱgene;in the simple osteogenic inducement group, they were cultured in the condition medium. Then the expressions of Cad- Ⅱ protein were determined and the alkaline phosphatase (ALP) activities and the expressions of ostcocalein were measured at 3, 7, 14 and 21 days for comparison between the 2 groups. Results The ALP activity and positive expression of osteoealcin were regulated significantly higher in the transfeetion group than in the simple osteogenic inducement group at different times (P <0.05). The mineralized nodes began to appear at 14 days in the 2 groups and increased with time. Conclusion Cad-Ⅱgene transfeetion can promote differentiation of hBMSCs into the osteoblasts.

Objective To observe the effect of inferior vena cava filter (IVCF) on prevention of bone cement implantation syndrome (BCIS). Methods Ten sheep were divided into 2 even groups, BCIS and LVCF intervention ones. First IVCF was implanted into the inferior vena cava through cervical vena-right atrium pathway under fluoroscopic monitoring to observe the influence of IVCF on BCIS. Then BCIS was es-tablished in the same sheep by compressing 10 mL of bone cement into a sheep medullary canal after mutilation of the left femur. Arterial blood pressure, heart rate, central venous pressure (CVP) and blood gas were monitored, while an ultrasonic device was utilized to monitor fat embolisms in the right atriums of the sheep. Oil red staining was performed to detect fat embolisms in pulmonary arteries after the sheep were executed. Results In BCIS group, dotted uneven resonances were found in the right atrium and right ventricle when the medullary canal pressure was increased to 120 mm Hg, indicating embolisms in the right chambers. The dotted resonances were increased to ponderous, snowflake-like ones as the medullary canal pressure climbed up. At the same time, blood pressure and Pa02 dropped significantly, the systolic blood pressure dropped to (80±11) mm Hg and PaO<.2> to the minimum 25 minutes after cone cement implantation. The heart rate and CVP increased continuously. The blood gas assay indicated respiratory and metabolic acidosis. The oil red staining showed bulk fat embolus in pulmonary arteries. But in IVCF group, the similar resonances were not observed throughout the surgery and the medullary canal pressure climbed to 400 mm Hg, reaching the maximum of our pressure gage range. The blood pressure, PaO2, heart rate and CVP did not change much compared to those before implantation. The blood gas and pulmonary oil red staining showed few changes either. Conclusion IVCF implantation can prevent the genesis of BCIS.

Objective To discuss clinical effects of early (<48 hours after injury) fraeture exter-nal fixation in treatment of severe traumatic brain injury (TBI) combined with extremity fracture. Meth-ods The study involved patients with no statistical difference in aspects of age, sex, GCS, fracture ,distri-bution and general condition. According to different treatment methods at early stage (<48 hours), the pa-tients with TBI were divided into Group A (early extremity fracture external fixation) and Group B (early extremity fracture traction or cast immobilization). A comparative observation was done on complications in-cluding bedsore, pneumonia and deep venous thrombosis and on duration in ICU, hospitalization, time for fracture healing and mortality in two groups. Results Incidence rate of bedsore, pneumonia, deep ve-nous thrombosis and mortality in Group A was lower than that in Group B (P<0.05), and Group A had shorter time for ICU, hospitalization and fracture healing (P < 0.05). Conclusion For patients with se-vere TBI combined with extremity fracture, early fracture external fixation is more effective to reduce com-plications, shorten the recovery time and reduce mortality, compared with conservative methods.

Objective To explore regional characteristics of road traffic injury in urban Beijing through analysis of the investigation by a single hospital. Methods Using Emergent Road Traffic Injury Questionnaire we designed, we performed a survey for 2 weeks on all the patients with road traffic injury who had sought medical care in the emergency department of our hospital. A comparison was made between them and other patients at the emergency department at the same period. Results From 8:00 on 25 April 2006 to 8:00 on 8 May 2006, 18 emergent cases of road traffic injury were treated. They accounted for 0.54% of all the emergency patients and 4.5% of all the trauma patients. They were 7 males and 11 females, with an average age of 48.3±14. 3 years. The average time to hospital was (26.8±14.4) rain. Seventeen cases of injury happened in the street, 1 in the highway;15 in Xicheng District, 1 in Haidian District, and 2 in the suburbs. They included 8 pedestrians, 9 riders, and 1 passenger. They were injured by 12 light vehicles, 2 heavy vehicles, 2 special vehicles, and 2 bicycles. Twelve patients had injury at extremity, 3 at spine, and 3 at multiple sites, They received treatment only in Emergency Department. No one was dead or hospitalized. Conclusions Contrary to common belief, road traffic injury patients seem to account for a small part of trauma patients and the injury tends to be moderate. Females and extremities may be more likely to get injured.

Objective To determine the optimal time for intravenous injection of bone marrow mesenchymal stem cells(BMSCs)by observing the effects of inflammation after spinal cord injury on the survival and immigration of BMSCs injected intravenously.Methods Forty SD rats were randomized into 1 non-injury group and 7 spinal cord injury(SCI)groups in which the injured spinal cords were harvested at 0 h, 6 h, 12 h, 24 h, 3d, 5 d, and 7 d respectively.Hematoxylin and eosin(HE)staining was used to e-valuate the histopathologic changes.Myoleperoxidase(MPO)activity was measured to study the duration of polymorphonuclear leukocyte(PMNL)infiltration in the spinal cord after injury.Another 40 SD rats were also randomly divided into 1 non-injury group and 7 transplantation groups in which intravenous injection of BMSCs was performed at 0 h, 6 h, 12 h, 24 h, 3d, 5 d, and 7 d after SCI.The survival counts and immigration distance of BMSCs in the spinal cord in all the groups were measured.Results The PMNL infiltration into the injured spinal cord and the MPO activity started from 6 h after SCI.There were a large number of infiltrating PMNL in the spinal cord and the MPO activity reached its peak value at 24 h.The infiltrating PMNL in the injured spinal cord began to decrease and the MPO activity began to weaken from 3 d.Proliferation of glial cells and formation of empty holes in the spinal cord started from 5 d.The survival counts of BMSCs were smaller but the immigration distance of BMSCs was longer in the 0 h, 6 h, 12 h, and 24 h transplantation groups.The survival counts of BMSCs were larger and the immigration distance of BMSCs was longer in the 3 d transplantation group.The survival counts of BMSCs were smaller but the immigration distance of BMSCs was shorter in the 5 d and 7 d transplantation groups.Conclusion The optimal time for intravenous injection of BMSCs may be 3 days after SCI.

Objective To explore the role and mechanism of stress stimulation in the repair process of the rotator cuff. Methods The supraspinatus tendon was cut off at the osteotendinous junction (OTJ) and then sutured in situ (Carpenter's model). The experimental group started treadmill running after one week immobility, and the control group were free in the cage. All animals were sacrificed at 4 time points (2, 4, 8 and 16 weeks after operation). Histological changes, immunohistology of yon Willebrand factor and tenascin-C at OTJ were compared between the 2 groups. Results There was no significant difference between the 2 groups in the early repair period. Significant differences between the 2 groups in histology and angiogenesis appeared 8 weeks after operation, and significant differences in expression Of Tenascin-C appeared 16 weeks after operation. Conclusion As stress stimulation can promote angiogenesis and expression of Tenascin-C at OTJ, facilitating the reconstruction of bone and tendon, it plays a critical role in the repair process of rotator cuff tear.

Objective To study the clinical effect of cohesive elastic bandage (CEB) after operative treatment of ankle fractures. Methods After surgery, 60 patients with ankle fracture were randomly as-signed to 2 even groups: CEB dressing group and common dressing group. Functional exercise started the next day after operation. Comparison was made between the 2 groups in drainage, displacement and swelling. Results In CEB dressing group, the volume of drainage was (34.6±18.1) mL, the rate of displacement 6.7%, and the swelling was slight in 21 patients, moderate in 5 and severe in 4. In common dressing group, the volume of drainage was (85.1±17.1) mL, the rate of displacement was 63.3%, and the swelling was slight in 7 patients, moderate in 12 and severe in 11. The differences were significance(P<0.05) . Conclusion Use of CEB after surgery for ankle fractures may alleviate swelling, reduce bleeding effectively, and benefit early functional exercise.

Objective To explore methods of easy treatment of bulk trauma patients caused by Wenchuan earthquake.Methods Early treatment was done on 1123 patients including extremity injuries in 925,spinal injuries in 65,brain injuries in 46,thoracic injuries in 53 and abdominal injuries in 72.There were 809 patients with single part injury and 314 with multiple injury.Emergent operation was performed in 67 patients including 13 with liver repair,14 with spleenectomy,three with mesentery blood vessel repair,six with repair of multiple abdominal organ injuries,four with repair of raptured diaphragm and injured organs,12 with evacuation of intracranial hematoma,four with lung repair,five with partial resection of lung and bronchus,one with pericardium discission and five with internal fixation of ribs.Early operation was carried out in 166 patients including 105 with only debridement,36 with debridement plus external fixation and 25 with amputation.Results Of all,406 patients were cured,673 were transferred to higher level hospitals after fundamental treatment and three died.Conclusion Staged treatment is suitable for early management for bulk trauma patients.Damage control technique should be applied early for critically severe patients and those with severe disease of heart and lung.Repeated examination is efficient to avoid delayed diagnosis and treament.

Objective To investigate the mechanism of mastoparan-1 (MP-1) antagonizing lipopolysaecharide (LPS) in vitro. Methods The affinity of MP-1 for lipid A was assayed by biosensor, and the neutralization of MP-1 on LPS (2 μg/L) was detected by kinetic turbidimetric limulus test. After exposing fluorescin isothiecyanate (FITC) labeled LPS (FITC-LPS) to MP-1 at different concentrations (5, 10, 20, 40 μmol/L), the binding of FITC-LPS to murine RAW264.7 cells was analyzed by laser scanning confocal microscopy. The influence of MP-1 on TLR4 expression in RAW264.7 cells stimulated by LPS (100 μg/L) was detected by immunoeytochemieal staining. The expressions of TLR4, TNF-α and IL-6 at the gene and protein level were detected by RT-PCR and ELISA after exposing LPS (100 μg/ L) stimulated RAW264.7 cells to MP-1 at different concentrations. The effect of MP-1 on the viability of RAW264.7 cells was detected by MTT assay. Results MP-1 had high affinity to lipid A and could neutralize LPS. MP-1 at 10 μmol/L significantly inhibited not only binding of FITC-LPS to RAW264.7 (P < 0.05), but also protein and gene expressions of TLR4, TNF-α and IL-6 in LPS stimulated RAW264.7 cells in a dose-dependent manner (P < 0.05). No toxic effect of MP-1 on the viability of RAW264.7 cells was found (P > 0.05). Conclusions MP-1 inhibits cell viability mediated by LPS, which may be related to its neutralization of LPS and inhibition of binding of LPS to RAW264.7 cell membrane receptors.

Objective To investigate the methods and therapeutic effects in reconstructing and restoring the knee stability of floating knee injury. Methods A total of 38 patients with floating knee injury combined with acute knee instability treated from January 2000 to January 2006 were retrospectively studied to evaluate the efficacy of different procedures. Results All patients were followed up for 1-4 years (mean 1.5 years), which showed fracture healing in all patients. There occurred postoperative wound infection in three, internal fixator loosening in two, anterior cruciate ligament laxity in one and osteearthritis in two. According to Score of Hospital for Special Surgery (HSS) for knee function,the knee function was excellent in 32 patients, good in five and fair in one, with excellence rate of 84%. Conclnsions During the treatment of floating knee injury, attention should not only be paid to the reconstruction of the bone continaity, but also to the restoration of ligaments, meniscus, joint capsule and muscles.