The mrp gene of SS2 human strain Habb was truncated and cloned into a prokaryotic expression vector pGEX4T-2,and a fusion-expressed protein MRP-GST of 61 000 was obtained in E.coli.The GST was cut from MRP-GST with thrombin protease to gain the purified MRP of 35 000 which showed a strong reaction to the SS2 positive sera in Western blotting.BALB/c mice were immunitied intraperitoneally with purified MRP protein.Murine myeloma cells were fused with the splenocytes of the immunized mice after the third immunization.An indirect ELISA coated with purified MRP was used to screen hybridomas for production of specific antibody.The six McAb recognized MRP specially.According to the results of 71 standard strains (48 SS and 34 SS2)by Sandwich ELISA,the coincidence rate was 97.2%,but for 34 SS standard serotype was 100 %.The ELISA method has a potential value for clinical and epidemiological applicationgs.

Objective To enhance understanding of the vertebral compressed fracture in old patients so as to reduce its misdiagnosis. Methods 30 aged patients with vertebral compressed fracture were treated from 1998 to 2004 in our department. Their clinic data were retrospectively analyzed. There were 27 males and 3 females, aged from 70 to 90 years (averaging 82.5 years). Results All the patients were diagnosed definitely. There were 2 cases of T11 fracture, 13 cases of T12 fracture, 11 cases of L1 fracture, 3cases of L2 fracture, and 1 case of L3 fracture. At first 1 case was overlooked, and segmental positioning was wrong in 3 cases but the mistakes were corrected later. Conclusion Meticulous review of the history and clinical manifestation in addition to supplemental imageological examination are essential to early diagnosis of the majority of vertebral compressed fractures. As for some difficult early diagnoses, fat suppression MRI and nuclide bone scanning are helpful.

Objective To evaluate efficacy,safety and complication of percutaneous kyphoplasty (PKP) for osteoporotic vertebral compression fracture (OVCF) in≥90 years patients.Methods Clinical data of 56 cases aged ≥ 90 years with osteoporotic vertebral compression fracture undergoing percutaneous kyphoplasty were retrospectively analyzed.Visual analog scale (VAS) score,analgesics administration score,locomotor activity score,bone cement leakage and incidence of refracture were evaluated before and 3 days after treatment,and at the last follow-up.Results The mean follow-up was 18.6 months (6-32 months) in all patients.The mean VAS score was (7.1 ±2.1) before treatment,(2.6±1.1) at 3 days after the procedure,and (1.8±0.7) at last follow-up,respectively (F=455.794,P＜0.001).Analgesics administration score were (2.0±1.7),(1.4±0.5) and (1.1±0.7) respectively before and 3 days after treatment,and at the last follow-up (F=9.631,P＜0.001).Locomotor activity score were (2.5±0.6),(1.2±0.5) and (1.0±0.3)before and 3 days after treatment,and at the last follow-up (F=63.254,P＜ 0.001) respectively.Bone cement leakage occurred in 10 cases(17.9％),recurrent fracture in 6 cases(10.7％),cerebrospinal leak in 3 cases (5.3％),and nerve root stimulation in2 cases(3.6％).Total complication rate was 33.9％(19/56),and all complications were transient and well tolerated.Conclusions Kyphoplasty for osteoporotic vertebral compression fracture in the very elderly is effective and safe.It alleviates fracture-induced pain,reduces analgesic drug use and improves spinal activity,and provides a better choice for minimal invasive treatment for nonagenarian OVCF patients.

Objective To evaluate the surgical results of spinal stenosis in the elderly and to investigate the indications , surgical technique and factors which may contribute to the outcome. Methods A retrospective study was held, 304 patients aged 65 and over who had different kinds of decompression laminectomy for lumbar spinal stenosis between Jan 1990 and Jun 2005 were recruited. The mean patient age at surgery was 70.4 years (65-86 years old). Results One hundred and seventy-five cases had co-existing illnesses, 62 had concomitant degenerative spondylolisthesis, 138 had spinal instrumentation. Functional results were graded as excellent, good, fair and poor: 86. 8% excellent or good, 11. 2% fair and 6 cases poor. Four patients had re-operations because of post operation hematomas. Multivariate analysis revealed that age, sex, co-morbidity score, number of levels decompressed, and degenerative spondylolisthesis did not predict bad outcomes. Conclusions The surgical results of spinal stenosis in the elderly are favourable and comparable to those reported for the general population . Carefully perioperative preparation is very important in the treatment of elderly patient with lumbar spinal stenosis.

Objective To evaluate the effects of posterior segmental pedicle screw instrumentation and augmentation using calcium sulphate cement in treatment of Denis type B thoracolumbar burst fractures.Methods Forty patients with Denis type B thoracolumbar burst fracture treated between January 2011 and December 2012 were reviewed retrospectively.Twenty patients received posterior short-segment pedicle screw fixation in conjunction with screw placement at the level of fracture and calcium sulphate augmentation without posterolateral fusion (combined treatment group),but 20 patients underwent traditional short-segment pedicle screw fixation (conventional treatment group).Radiographs and CT scans evaluated local kyphotic angle on the spot of injury,anterior height of the injured vertebra,and canal encroachment before and after operation and at final follow-up.Meanwhile,visual analogue score (VAS),Oswestry disability index (ODI),and neurologic status based upon ASIA 2000 were assessed.Results Mean follow-up period was 15 months (range,12-24 months).Vertebral height restoration was equivalent of the two groups immediately after operation,but better result of kyphosis correction was found in treatment group than in control group (P ＜ 0.05).Anterior vertebral height and kyphotic angle significantly improved in treatment group compared to control group at final follow-up (P ＜ 0.05).Clinical and neurologic outcome evaluation were similar between the two groups.No implant failure occurred at follow-up.Conclusion For Denis type B thoracolumbar burst fractures,posterior segmental pedicle screw fixation augmented with calcium sulphate is effective for reducing correction loss and implant failure,compensating for the deficiencies of conventional fixation.

Objective To evaluate the clinical efficacy of treatment of severe thoracolumbar burst fractures by posterior short-segment instrumentation without spinal fusion and assess radiographic imaging and function recovery after surgery.Methods Thirty-eight patients with severe monosegmental thoracolumbar burst fractures treated between July 2011 and March 2013 were analyzed retrospectively.Operation procedures were posterior short-segment pedicle screw distraction reduction and fixation combined with screw insertion to the injured vertebrae and calcium sulphate augmentation.In addition,there was no need for posterolateral interbody fusion.X-ray and CT were performed before and after operation to evaluate local kyphotic angle,anterior fractured vertebral body height and canal encroachment.Visual analogue scale (VAS) and Oswestry disability index (ODI) were assessed before and after operation as well as in follow-up.Results All patients were followed up for average 14 months (range,3-20 months).Local kyphotic angle was (21.2 ±4.3)° before operation,(3.5 ± 1.8)°immediately after operation,and (4.8 ± 2.7) ° in final follow-up.Relative anterior vertebral height was (54.8 ± 14.6)％ before operation,(91.7 ± 8.0)％ after operation,and (87.2 ± 6.0)％ in final follow-up.Mean canal encroachment was (48.0 ± 4.5)％ preoperatively,(23.8 ± 7.8)％postoperatively,and (8.8 ± 4.6) ％ in final follow-up.In final follow-up,six patients with American Spinal Injury Association (ASIA) grade C on admission showed improvement to grade D (n =2) and grade E (n =4) ; 10 patients with ASIA grade E on admission showed improvement to grade E; 22 patients with grade E had no changes.ODI and VAS scored 15.5 ±8.8 and 2.3 ±0.8 in final follow-up with substantial improvement from those before operation (P ＜ 0.01).Complications from internal fixation were not found during follow-up.Conclusion Posterior short-segment fixation without fusion is one of the foremost effective methods for severe thoracolumbar burst fractures,for it can effectively restore the sagittal spinal alignment and the fractured vertebral body height.

BACKGROUND: Peak bone mass and standard deviation (SD) in different regions are varied, which have great influence on diagnosis of osteoporosis. To establish a complete database can provide accurate evidence for osteoporosis diagnosis. OBJECTIVE: To investigate the influence of bone mineral densities (BMD) and their SD of young people on the detective rate of osteoporosis in general population. DESIGN, TIME AND SETTING: Investigation analysis was performed at Beijing, Shanghai, Guangzhou, Nanjing, Jiaxing and Chengdu between January 1997 and December 1999. PARTICIPANTS: 11418 subjects from related 6 centers of BMD reference database in China were investigated and analyzed using prospective and retrospective methods, including 3 666 males, and 7 752 females aged 20-90 years. Of them, 2385 were from Beijing, 1178 from Guangzhou, 1404 from Shanghai, 2938 from Nanjing, 1425 from Chengdu, and 2088 from Jiaxing. The subjects were selected from community investigation, physical examination volunteers. METHODS: BMD of the lumbar spine (L2-4) and the hip in 11, 418 subjects from the related 6 centers in China was measured with GE-Lunar dual energy X-ray absorptiometry (DXA) and the BMD reference database was established. The accuracy rate of the inner machine was 0.3%-0.7%, and the accuracy of different machines averaged 1.1%. MAIN OUTCOME MEASURES: Lumbar BMD distribution of different age groups from 6 centers; influence of young people's BMD and its SD on detective rate of osteoporosis. RESULTS: Different BMD and SD were found in the individual subject from 6 centers, and the maximum differences were 0.098 g/cm2 and 0.027 g/cm2. With mean BMD and SD of the individuals from 6 centers as references, different T-scores and the detective rates of osteoporosis derived from the T-scores were found in the same group. The detective rate increased by 1.6% when BMD of the young people increased by 0.01 g/cm2 (positive correlation), but the detective rate decreased by 4% when SD increased by 0.01g/cm2 (negative correlation). CONCLUSION: Changes in BMD and SD of the young people can influence the detective rate of osteoporosis. To achieve comparability for the detective rate of osteoporosis in different centers, the specific reference database should be established for the same race, the same area, and the same bone densitometry machine. The T-score should be determined with the normal BMD and SD of the young, people as the reference database.

OBJECTIVE To prepare and characterize curcumin nanomicelles （hereinafter referred to as Cur/mPEG-PBLA micelles）， and to evaluate the in vitro hepatoprotective activity against alcohol liver disease （ALD）. METHODS Cur/mPEG-PBLA micelles were prepared with the dialysis method using methoxy-poly（ethylene glycol）-poly（β-benzyl-L-aspartate） （mPEG-PLGA） as the carrier. The appearance and microscopic morphology of Cur/mPEG-PBLA micelles were observed， and particle size， polydispersity index， Zeta potential， encapsulation efficiency and drug loading content were all detected. The in vitro release， pH stability， thermal stability， dilution stability， storage stability， plasma stability tests， and hemolysis experiments were all performed. The cell model of ALD was established with anhydrous ethanol intervention using human liver cancer cells and normal liver cells as objects， Cur reference solution as reference， to evaluate in vitro preventive and ameliorative effects of Cur/mPEG- PBLA micelles on ALD. RESULTS The prepared Cur/mPEG-PBLA micelles exhibited a pale-yellow milky light， with a spherical shape and uniform distribution. The average particle size was about 140 nm， and the polydispersity index was less than 0.3. Zeta potential was （－8.15±0.05） mV； the encapsulation efficiency was （73.26±3.16）%， and the drug loading content was （4.87± 0.42）%. The cumulative release of Cur reference substance was close to 80% at 10 h； the cumulative release of Cur/mPEG-PBLA micelles at 8 h was 28.94% and only 48.25% at 48 h. pH stability and thermal stability of Cur/mPEG-PBLA micelles were better than those of Cur reference solution； Cur/mPEG-PBLA micelles showed good dilution stability， storage stability and plasma stability， and would not cause hemolysis. Cur reference solution and Cur/mPEG-PBLA micelles had varying degrees of in vitro preventive and ameliorative effects on ALD in two types of cells； after 48 h of application， the above effects of Cur/mPEG-PBLA micelles were significantly better than those of Cur reference solution at the same mass concentration （P＜0.05）. CONCLUSIONS Cur/mPEG-PBLA micelles can improve pH stability and thermal stability of Cur， delayits degradation rate， and have better in vitro hepatoprotective activity against ALD.