The underlying molecular pathogenesis of osteosarcoma remains poorly understood. The transcription factor MEF2D promotes the survival of various types of cells and functions as an oncogene in liver cancer. However, its potential contribution to osteosarcoma has not been explored. In this study, we investigated MEF2D expression and function in osteosarcoma, finding that MEF2D elevation in osteosarcoma clinical specimens was associated with patients' poor prognosis. MEF2D suppression was shown to decrease the proliferation of osteosarcoma cells, while forced expression of MEF2D was able to promote the proliferation of normal bone fibroblast. Notably, MEF2D silencing abolished osteosarcoma tumorigenicity in an animal model. Mechanistic investigations revealed that MEF2D silencing triggered G2–M arrest in osteosarcoma cells by suppressing RPRM and CDKN1A. miR-144 was found to suppress the expression of MEF2D in osteosarcoma cells. Collectively, our results demonstrated that MEF2D is a candidate oncogene for osteosarcoma and a potential molecular target for cancer therapy.

Bone marrow mesenchymal stromal cells (BMSCs) are the common precursors for both osteoblasts and adipocytes. With aging, BMSC osteoblast differentiation decreases whereas BMSC differentiation into adipocytes increases, resulting in increased adipogenesis and bone loss. In the present study, we investigated the effect of asiatic acid (AA) on adipocytic differentiation of BMSCs. AA inhibited the adipogenic induction of lipid accumulation, activity of glycerol-3-phosphate dehydrogenase, and expression of marker genes in adipogenesis: peroxisome proliferation-activated receptor (PPAR)γ, adipocyte fatty acid-binding protein (ap) 2, and adipsin. Further, we found that AA did not alter clonal expansion rate and expression of C/EBPβ, upstream key regulator of PPARγ, and binding activity of C/EBPβ to PPARγ promoter was not affected by AA as well. These findings suggest that AA may modulate differentiation of BMSCs to cause a lineage shift away from the adipocytes, and inhibition of PPARγ by AA is through C/EBPβ-independent mechanisms. Thus, AA could be a potential candidate for a novel drug against osteoporosis.

Objective Through inspecting in vitro fibrillogenesis of the young and the old rat tail tendon collagen,as well as comparing the morphological changes of the lumbar cancellous bone collagen,to study the influence of age in fibrillogenesis.Methods The tail tendon(5 g) of 2-week and 20-month rats,was obtained,and the tail collagen was extracted by the dilute acetic acid.The extracted collagen was freezed-dried in low temperature.15 mg tail collagen were take from 2-month-old and 20-month-old rats.Each wss divided into three groups,5 mg in each group,and the collagen was melted in 10 mmol·L-1 acetic acid solution at 4℃,the titanium metal screws were infiltrated into the solution.After adding buffer the fibrillogenesis was taken in 37℃.The screws were picked up separately at 2,4 and 8 h,and the morphological changes of collagen of the surface of the screws were observed under scanning electron microscope(SEM).10 2-week rats and 10 20-month rats were sacrificed to remove the L3 vertebral body,the regular specimen were made.The specimens were repeatedly washed by using physiological saline,dehydrated,and sprayed gold,and then observed under SEM.Results The tail collagen of rats in two groups did not take fibrillogenesis in the screw surface at 2 h.At 4 h,the tail collagen of 20-month-old rats was gathered into the irregular and massive collagen polymer,no collagen fibers wre formatted in surface of the screw.The tail collagen of 2-week-old rats turned into 0.07-0.20 μm collagenous fibres.At 8 h,the tail collagen of 20-month-old rats in the surface of the screw polymerized into the different size collagen polymers,no formation of collagen fibers.The tail collagen of 2-week-old rats formated 0.65-1.35 μm collagen fibers.The SEM results showed that the collagen of 2-week rat trabecular bone cross-linked into uniform collagen fibers.The fibers were closely arranged,and the orientation was consistent.The widths of the collagen fibrils of 20-month-old rat trabecular bone were not consistent.The arrangement of the fibrils was loose,sparse and disordered,and the orientations of the oblique collagen fibers between them were unorganized.Conclusion With the increaes of age,the fibrillogenesis capacity of type Ⅰ collagen gradually reduce,and lead to the morphological changes of bone collagen fibers,which may be very important reasons of senile osteoporosis and increased fracture risk.

BACKGROUND:One of the reasons for poor neuroregeneration after central nervous system injury is the presence of inhibitory factors such as Nogo. Here, we tested the inhibition of Nogo by RNA interference both in vitro and in vivo, using recombinant adenovirus-mediated transfection of short hairpin RNAs, to explore a new method of treatment for spinal cord injury.METHODS:We designed and cloned two Nogo-specific short hairpin RNAs and an unrelated short hairpin RNA, packaged the clones into adenovirus, and amplified the recombinant virus in 293 cells. We then tested the inhibition of Nogo expression both in vitro in adenovirus-transfected oligodendrocytes and in vivo in spinal cord tissue from adenovirus-transfected spinal cord injury model rats. We tested Nogo expression at the mRNA level by reverse-transcription PCR and at the protein level by Western blotting and immunohistochemistry.RESULTS:In vitro, the two specific Nogo short hairpin RNAs decreased Nogo mRNA expression by 51% and 49%, respectively, compared with Nogo expression in cells transfected with the unrelated control small hairpin RNA (P < 0.005). Similarly, Nogo protein expression decreased by 50% and 48%, respectively (P < 0.005). In vivo, in spinal cord injury model rats, the two specific Nogo short hairpin RNAs decreased Nogo mRNA expression by 45% and 40%, respectively, compared with Nogo expression in spinal cord injury model rats transfected with the unrelated control short hairpin RNA (P < 0.005). The Nogo protein level was similarly decreased.CONCLUSIONS:We were successful in specifically downregulating Nogo at the mRNA and protein levels by adenovirus-mediated delivery of short hairpin RNAs, both in vitro and in vivo. This confirms the effectiveness of RNA interference for the inhibition of Nogo gene expression and the efficiency of using adenovirus for delivery. Thus gene therapy may be an effective treatment for spinal cord injury.

Objective To study the feasibility of vertebral internal fixation using deer as animal models by comparing the biological parameters of deer,sheep and human lumbar and to provide the morphological parameters,the bone density,and the biomechanical data of laboratory animals for related medical research.Methods 10 sets of fresh sika deer lumbar,10 sets of fresh sheep lumbar,and 10 sets of fresh lumbar of male cadavers were selected as the materials.The morphological observation of the lumbar vertebral bodies and pedicles of three groups were taken,and the cancellous bone density,ultimate stress and elastic modulus were measured and compared.Results There were significant differences of heights of right vertebral pedicles between three groups(P0.01);the deer had the largest one,the sheep followed,and the human had the smallest one.There were remarkable differences of the widths of right vertebral pedicles and anterior disc heights between three groups(P0.05);the human had the largest one,the deer followed,and the sheep had the smallest one.There were significant differeces of apparent density,elastic modulus and ultimate stress between three groups(P0.05);the sheep had the largest one,the deer followed,and the human had the smallest one.Conclusion Deer lumbar is more similar as that of human according to anatomic form and biomechanics compared with the sheep lumbar.Therefore,deer is a more suitable to set up animal model for vertebral internal fixation research.

临床上以截瘫为首发症状的老年腹主动脉栓塞较少见,现报告1例.1 病历摘要患者,男性,69岁,因双下肢运动、感觉消失,尿便困难45 h,于2010年12月16日16时入院.入院45 h前无明显诱因出现双下肢运动、感觉消失,排尿困难,于当地医院,给予导尿等对症治疗,发现双下肢变凉、皮肤苍白,转入我院就医,急诊以"双下肢截瘫"收入我科.病程中意识清楚,自觉略腹胀,未排大便,尿中带血.既往否认高血压病史、冠心病史及糖尿病史.人院查体:体温:36 0℃,脉搏:80次/rin,呼吸:18次/min,血压:140/90 mmHg.神清语利,表情自如,被动体位,查体合作.双侧腹股沟区及大腿前方、阴茎、阴囊及会阴部可见皮肤瘀斑.专科情况:平双侧髂嵴水平以下皮肤浅感觉消失,腹壁反射、提睾反射消失,会阴部感觉及球海绵体反射、肛门反射消失.右侧股动脉未触及搏动,左侧股动脉可略触及搏动.双下肢肌张力略高,双下肢股四头肌、胫前肌、胫后肌群及拇长伸肌肌力0级.

目的 比较正常和骨性关节炎动物模型膝关节外侧副韧带的蠕变特性,确定骨性关节炎对外侧副韧带蠕变特性的影响.方法 在日本岛津电子万能试验机上对正常和病态组各10个试样进行蠕变实验.蠕变实验的应力增加速度为0.01MPa/s,实验时间为7200s,采集100个数,以一元线性回归分析的方法处理实验数据.结果 正常和病态组外侧副韧带蠕变最初600s变化较快,之后应变缓慢上升,蠕变曲线是以指数关系变化的.正常组7200s蠕变量1.489%,病态组7200s蠕变量1.175%.结论 骨性关节炎对膝关节外侧副韧带蠕变特性具有一定影响.

颈椎过伸性损伤(Hyperextension injury of the cervical spine,HEICS)是伸展外力作用于头面部,颈椎过度伸展所引起的颈椎损伤.过伸性颈椎损伤者根据暴力程度不同,可引起不同程度的颈脊髓损伤,轻者可无明显神经症状,重者可导致肢体瘫痪,甚至危及生命.但是HEICS,尤其是受伤早期临床症状不明显,而颈部X线筛选检查无明显异常者,常常被临床医生忽略或误诊.同时,HEICS的治疗目前临床上尚存在分歧[1].本文对我院收治的37例老年性HEICS患者的临床资料进行回顾性分析.

目的:探讨老年患者全髋关节置换术(THR)后深静脉血栓(DVT)的防治。方法:对45例THR术后患者联合应用药物和物理方法,防治DVT的发生。结果:45例中有44例没有发生DVT,有效率达97.7%。结论:应用药物和物理方法联合防治THR术后DVT的发生经济、安全,值得临床推广。

Objective To construct iRNA expression vector of Nogo receptor gene.Accordingly it can establish foundation for promoting reclamation of central nerve axis and exploring new path of the treatment of spinal cord injury in clinic.Method The sequence of NgR was found in Gene Bank.We designed and synthesized Oligo DNA corresponding with NgR miRNA using the software in www.invitrogen.com.The Oligo DNA was connected with BLOCK-iT Poll miR RNAi Expression Vector,And was transformed into competence Eco.li TOP10.Result the custom-crafted Vector,BLOCK-iT Poll miR RNAi / NgR,was Sequenced and identified using BamHⅠ and XhoⅠ.It is discovered that the Oligo DNA of NgR miRNA had been cloned into BLOCK-iT Poll miR RNAi Expression Vector correctly.Conclusion iRNA expression vector of Nogo receptor gene is constructed successfully.

OBJECTIVE:To evaluate the clinical effect of external tissue expansion in the repair of massive skin and soft tissue defects.METHODS:From August 1998 to January 2004, 10 patients with massive skin and soft tissue defects ( the area ranging from 10 cm x 4 cm to 24 cm x 15 cm) , including 7 with wounds in the leg, 2 with wounds in knee region, and 1 with wounds in the forearm, were enrolled in the study. All patients were subjected to external tissue expansion together with external skeletal fixation for 2 -3 weeks, then the wounds were closed with suturing or supplemented with skin flaps.RESULTS:The defects were closed completely after external expansion in 4 cases, and in other 5 cases the wounds were significantly decreased in area, and the residual wounds were covered with free skin grafting. In I case the wound could only be reduced in size, and the residual wound was closed with a local flap. Follow-up from 1 to 12 months showed that the wounds were closed with normal cutaneous sensation and good appearance.CONCLUSION:External skin expansion is a simple, economical method for repair of massive skin soft-tissue defect, which can significantly be reduced or entirely closed.

目的 利用RNA干涉(RNAi)技术使特定的基因(Nogo)沉默,探索脊髓损伤的治疗方法.方法 设计有小发夹结构的两条DNA序列,PCR扩增带有U6启动子的小发夹,腺病毒包装重组体,转染少突胶质细胞,采用Western blot法分析Nogo-66的蛋白表达水平.结果 成功地构建了靶向Nogo基因RNAi的带有U6启动子的小发夹重组体,Nogo-66蛋白表达水平明显下降.结论 靶向RNAi小发夹重组体经腺病毒包装后,成功转染少突胶质细胞并能有效抑制Nogo-66基因的表达.

目的探讨老年性陈旧性胸腰椎爆裂型骨折椎管侧前方减压脊柱稳定性的重建方法。方法12例老年性陈旧性胸腰段爆裂型骨折行左侧前方椎体次全切除、椎管减压钛网植骨融合TSRH短节段内固定。结果术后随访6~24个月(平均15个月),螺栓和螺钉无松动及断裂,3~6个月钛网内植骨全部融合,无假关节形成,瘫痪得到不同程度恢复,效果满意。结论侧前方减压手术减压彻底,TSRH加钛网植骨融合固定牢靠,无钛网塌陷及假关节形成,无须外固定,植骨融合快,瘫痪恢复满意,是治疗老年性陈旧性胸腰椎爆裂型骨折的有效方法。

目的探讨胸腰椎肿瘤侧前方减压脊柱稳定性的重建方法。方法9例胸腰段肿瘤全部行左侧前方椎体次全切除、椎管减压钛网植骨融合TSRH短节段内固定。结果术后随访6~12个月(平均9个月),螺钉无松动,TSRH短棒无断裂,6个月内钛网内植骨全部融合,无假关节形成,瘫痪得到不同程度恢复,效果满意。结论TSRH加钛网植骨融合固定牢靠,内固定材料生物相容性好,无须外固定,植骨融合快,瘫痪恢复满意,特别适合于椎体肿瘤切除后脊柱重建,是治疗胸腰椎肿瘤的有效方法。

Objective To obtain NOGO gene RNA interference (RNAi) small hairpin human involving U6 promotor by PCR.Methods The specific primers were designed, up primers including human U6 promoter and down primers including NOGO reverse complement target sequence were synthesized. Small hairpin RNA (shRNA) including human U6 promoter was directly amplified by PCR. PCR products can be cloned with T-vector. Digestion production was analyzed by 1% agarose gel electrophoresis. The plasmid 430 bp gene fragment was verified as positive recombinant plasmid to be sequenced. Results NOGO gene RNAi shRNA including human U6 promotor was amplified successfully.Conclusions The shRNA can be amplified quickly, easily and cheaply by PCR.

目的探讨胸腰椎肿瘤侧前方减压脊柱稳定性的重建方法。方法对12例胸腰段肿瘤全部行左侧前方椎体次全切除、椎管减压钛网植骨融合钛网内固定。结果术后随访6~12个月(平均9.6个月),钛板无断裂,6个月内钛网内植骨全部融合,无假关节形成,瘫痪有不同程度好转,效果满意。结论钛板钛网植骨融合固定牢靠,内固定材料生物相容性好,植骨融合快,瘫痪恢复满意,特别适合于椎体肿瘤切除后脊柱重建,是治疗胸腰椎肿瘤的有效方法。

s Objective To study the possibility of botinylated dextran amine (BDA) observing the local axinal transport of peripheral nerve and the changes of axoplasm in traumatic injured sciatic nerve.Methods BDA was injected into the sciatic nerve trunk of 24 adult rabbits by a microsyringe with different concentrations and different volume,and saline was injected into the matched control nerve.The sciatic nerve was sampled after a survival period of 6 to 48 h and observed under the light microscope and confocal microscopy.One,2,3,4,6 weeks after adult rabbit sciatic nerve transected injury,10% BDA solution was injected into the sciatic nerve trunk by a microsyringe proximal to the injury site.The sciatic nerve was sampled following pressure injection of BDA with survival time of 12 h,and the sections were directly examined under microscopy and confocal microscopy.Results Light microscopy:In the BDA injected region,positive labeled nerve fiber was stained with brown and purpl substance.Both myelin sheath and axis-cylinder were stained.No positive stained fiber could be detected in matched control nerve.Positive stained fiber could be viewed after 6 h following injection of 10% BDA solution in the proximal to the ligation of sciatic nerve.Confocal microscopy:After 6 h following injection of BDA,in the area proximal to the ligation,the axis-cylinder was brightly labeled while the myelin sheath was fluorescenced weakly.Up to three weeks and afterwords,in injuryed sciatic nerves stained fiber proximal to the ligation could be detected clearly under light microscopy and confocal microscopy.Conclusion The use of neural tracer BDA permits the directly identification of labeled axonal transport of sciatic nerve without difficult processing.Axonal transport was recruited after 3 weeks in break-fiber injured nerve when proximal and distal nerve stumps were kept intact.

目的研究足跟部的神经支配,总结神经卡压跟痛症的临床特点.方法31例病人局部封闭治疗,两例无效者手术松解.结果31例病人局部封闭治疗,治愈率74.2%,有效率93.5%,2例无效者经手术松解治愈.结论神经卡压是跟痛症发生的常见病因,要重视其诊断及治疗.