BACKGROUND:With the development of biochemistry and cel biology, fracture has being study deeper, blood supply has been known to be an important factor influencing the fracture healing. Endothelial progenitor cel s with good ability of angiogenesis wil have a good clinical prospect in fracture healing.
OBJECTIVE:To review the recent research of endothelial progenitor cel s in fracture healing.
METHODS:A computer-based online search of CNKI, Wanfang, PubMed databases was performed to col ect articles published between 1980 and 2014 with the key words“endothelial progenitor cel , fracture, neovascularization, angiogenesis”in Chinese and English. A total of 48 articles addressing endothelial progenitor cel for angiogenesis in fracture healing were included in result analysis.
RESULTS AND CONCLUSION:Increasing evidence has shown that endothelial progenitor cel s have great ability of neovascularzition and angiogenesis. Endothelial progenitor cel s used in tissue engineering scaffolds can promote the survival rate of scaffolds in vivo, which is appropriate to a great part of delayed union and nonunion patients. However, the large-scale treatment with endothelial progenitor cel s stil has many problems, such as isolation, culture and amplification of endothelial progenitor cel s in vitro, the number of transplanted cel s and selection of scaffolds for transplanted cel s, which need further research.

Applying cellular transplant methods in the treatment of peripheral nerve injury has become a new hot spot in tissue engineering and drawn much attention. Bone marrow stromal cells (BMSCs) grow fast and can be easily purified in vitro. Besides, they have the capability of differentiating into Schwann cells under specific conditions. For all the reasons above, BMSCs are considered good succedaneum of Schwann cells and new seed cells for tissue engineered peripheral nerve. In this review, the physiological functions and bionomics of Schwann cells and BMSCs are introduced, as well as various methods inducing BMSCs into nerve tissue cells and the foreground of the research.

Venous thromboembolism (VTE) is a kind of venous disorder that the abnormal condensation of blood within the vein,leading to complete or incomplete vein obstruction.VTE is mainly a combination of deep vein thrombosis (DVT)and pulmonary embolism (PE) and is an important complication after major orthopedic surgery (total hip arthroplasty,total knee arthroplasty,hip fracture surgery).Foreign literature reported that incidence rate of VTE after arthroplasty was as high as 42％-57％.Conventional notion was that DVT and PE were two different but interrelated types of VTE,while the latest research reported that the formation of DVT and PE after arthroplasty may be two events individually.Prevention of VTE after major orthopedic surgery includes general,pharmacological and mechanical methods.The efficacy of physical combined with pharmacological methods was better than drug prevention alone in preventing distal DVT.Dabigatran,apixaban,rivaroxaban and other new oral anticoagulants were better than low molecular weight heparin and other traditional medicines in effectiveness and safety.The effects of low molecular weight heparin are remarkable,while it cannot take orally.A recent study found that staged VTE prophylaxis,namely patients received low molecular weight heparin injection in hospital,and received aspirin,rivaroxaban or dabigatran orally after discharge is safe and effective in prevention of VTE.

Objective To explore the effects of cyclic tensile strain on the proliferation of cultured human osteoar-thritis chondrocytes. Methods The degenerated human cartilage came from a 66-year-old patient with osteoarthritis. The degree of degeneration was assessed by pathological diagnosis. Under the sterile condition, degenerated chondrocytes were cultured by enzymatic digestion. The toluidine blue staining, safranin O staining, and immunofluorescence staining of colla-genⅡwere used to identify the cultured cells. The third generation cells were seeded on the silicone rubber membrane carri-er, using the EF3200 mechanical tester equipped with BioDynamic bioreactor system, imposed a frequency of 0.25 Hz, stain 0, 5%, 10%and 15%load for 3 h. The proliferation activity was detected by flow cytometry. Results The proliferative in-dex (PI) increased with the magnitude value of cyclic tensile strain. The most significant increase of proliferation index was found in 10%group. Conclusion The proliferation of human osteoarthritis chondrocytes increases under some stress.

ObjectiveTo investigate the proliferation of rat's osteoblasts promoted by mechanical strain via the protein kinases C ξ(PKCξ) protein path-way.MethodsOsteoblasts were retrieved from SD rats' skulls in the sterilized environment.BioDynamic testing instrument was used to exert 2％ and 0％ mechanical strain on rats' osteoblasts for 180 min on the each group(2％ mechanical strain was experimental group and 0％ mechanical strain was control group); and the same method was applied on the rats' osteoblasts which pretreated with the classical PKC ξ inhibitor with 2％ mechanical strain (inhibitor group).The cell cycles of rats' osteoblasts were measured by flow cytometry; and Western blotting and immunofluorescence were used to detect expression of protein PKC ξ and phosphorylationed PKC ξ in the rats' osteoblasts.ResultsThe mechanical strain obviously increased the ratio of S period in the cell cycles.Compared to the control group and inhibitor group,a significant increase of the expression of protein PKC ξ and phosphorylationed PKC ξ in the osteoblasts was detected in the mechanical strain experimental group.ConclusionPKCξ can respond to the stimulus of the mechanical strain,which promotes the proliferation of osteoblasts through PKCξ pathway.And it plays an important role in the process of signal conduction.

ObjectiveTo measure the displacement parameters of the femoral head in space through CT three-dimensional reconstruction so as to re-understand impacted femoral neck fractures.MethodsFifty patients with impacted femoral neck fractures were included in the study.There were 17 males and 33 females.Bilateral proximal femurs of each patient were scanned by spiral CT preoperatively.Then these primitive CT data were reconstructed by Mimics 10.01 software.Registered the normal femur and fracture mirror model,the registered mirror model was generated a new mask in the CT cross-sectional images,marked key points in the masks and measured the displacement parameters of femoral head with three-dimensional measurement technology.ResultsIn the impacted femoral neck fractures,the femoral head displacement angle was 17.17°±10.40°,70％(35/50) of the patients had femoral head rotation angle was at 10° to 35°,and 30％(15/50) of the patients had femoral head space displacement more than 20°.The average displacement distance of femoral head center and the deepest point of fovea capitis were(6.49±3.60) mm and(10.42±5.92) mm,respectively.A high proportion of the impacted femoral neck fractures had a large of displacement in the three-dimensional space.It is not scientific to equal impacted femoral neck fractures to undisplaced fractures.ConclusionThree-dimensional reconstruction and digital measurement is a precise,efficient and convenient method for the measurement of femoral head displacement parameters in femoral neck fracture patients.The classic Garden classification for impacted femoral neck fractures has certain defects and limitations.Clinicians should re-understand impacted femoral neck fractures and choose more reasonable treatment.

Objective To investigate the effect of tension stress on the changes of mRNA expression of interleukin-17B (IL-17) and inducible nitric oxide synthase (iNOS) in rat discs.Methods Sixty-four female Sprague-Dawley rats were randomly divided into 4 groups:sham (S),tail-suspended (TS),tail-suspended with needle puncture (TSNP) and single needle puncture (SNP) groups.Tail-suspension device made rats of TS group and TSNP group hindlimb suspended,which exerted tension force on the coccygeal vertebrae disc;and aseptic needle puncture on the tail disc between the seventh and eighth coccygeal vertebrae (Co7/Co8)of TSNP,SNP group induced the inflammatory environment.The discs were harvested 4 weeks later.Measurements included gross observation,histological observation and real-time quantitative reverse transcription-polymerase chain reaction (RT-qPCR) analysis.Results Gross and histological examination found that varying degrees of degenerative changes in the annulus and nucleus in TS,SNP and TSNP groups,but not in the S group.RT-qPCR results showed that the mRNA of IL-17B and iNOS were significantly higher in the TSNP and SNP groups than that in the S group.The values of 2-△△Q were 12.99 and 8.12 in TSNP groups,and the 2-△△Q values of SNP group demonstrated 22.49 and 14.98 compared to S groups.Sole application of tension stress brought by the tail-suspension slightly enhanced the expression of IL-17B and iNOS,the values of 2-△△Q were 1.22 and 1.49,which didn't reach a statistically significant change.Compared with SNP group,the mRNA expression of IL-17B and iNOS in TSNP groups were shapely decreased,the values of 2-△△Q were-9.50 and -6.86 respectively.Conclusion Relatively low magnitude tension stress might play a key role in anti-inflammatory process and the relief of discogenic pain.

A total of 68 patients with histologically proven endometrial cancer were preoperatively evaluated with a 3.0 T magnetic resonance (MR) unit.Two radiologists interpreted the depth of myometrial invasion on T2-weighted and diffusion-weighted(DW) MR (b =700 s/mm2) imaging.Myometrial tumor spread was classified as superficial (＜ 50％) or deep (≥50％ myometrial thickness).Statistical methods included Kappa statistics for reader agreement,accuracy assessment and receiver operating characteristic analysis for diagnostic performance comparison.For assessing the depth of myometrial invasion,the diagnostic accuracy,sensitivity and specificity were as follows:T2-weighted imaging-reader 1st,61.8％,60.0％ and 65.2％;reader 2nd,66.2％,64.4％ and 69.6％ ; T2-weighted combined DW imaging-reader 1st,86.8％,84.4％and 91.3％ ; reader 2nd,89.7％,86.7％ and 95.7％.Reader agreement was excellent for T2-weighted combined DW imaging (Kappa =0.818).For assessing deep myometrial involvement,ROC analysis showed that the diagnostic accuracy was significantly higher on T2-weighted combined DW imaging than that on T2-weighted imaging.The AUC (area under the curve) values measured by two readers on T2-weighted and T2-weighted combined DW imagings were 0.626,0.879 and 0.670,0.912 respectively.The addition of 3.0T MR diffusion-weighted to T2-weighted imaging can improve the diagnostic performance of MR imaging in the assessment of myometrial invasion.

Objective To explore the angiogenesis&neovascularization effects of naringin treatment in ovariectomized rats’fracture healing. Methods Upper 1/3 transverse tibial fracture model 4 weeks later after ovariectomized were estimated and randomly divided into the naringin group and control group. Microfil perfusion technique was used to analysis the angiogene?sis situation at two weeks after bone fracture. HE staining was used to evaluate the level of angiogenesis&neovascularization of tis?sue from histological point of view. The relative expression of VEGF in the callus was identified by real?time polymerase chain re?action. Immunohistochemical technique was used to observe the vessel endothelial growth factor?2 in the callus of the two groups. Maximum fracture load was tested by three?point bend test. Results The vascular volume and vascular density were more in nar?ingin group than control group. The HE staining of the 2 week group slices shows that the VA, VN2 of the unit of high magnifica?tion vision of the naringin group was significantly larger compared to the control group. Real?time PCR revealed that the compara?tive expression of VEGF is more in naringin group than in control group; the positive number of VEGFR?2 is more in naringin group than in control group. Naringin can promote the maximum load of the callus. Conclusion Naringin can promote ovariecto?mized rats’angiogenesis&neovascularization in the early process of fracture healing. It may be act on the signaling pathway of VEGF/VEGFR?2.

Objective To assess the relationship between reconstruction of coronal trunk shift and changes of unfused segments after selective posterior thoracolumbar/lumbar curves fusion for idiopathic scoliosis.Methods Radiographic data of patients with thoracolumbar/lumbar idiopathic scoliosis who underwent selective posterior correction at our hospital from October 2005 to October 2011 with a minimum of 2 year follow-up period was retrospectively analyzed.Posteroanterior and lateral radiographs of the whole spine before surgery,after surgery and at the last follow-up were performed.Changes of coronal trunk shift during follow-up period were observed and multiple linear regression analysis was performed to determine its relationship with changes of upper thoracic curve,main thoracic curve,lumbar curve,distal unfused segments and coronal sacral inclination.Results Thirty-seven patients with 4 males and 33 females were included in this study.The average age was 14.6±2.0 years (range,12-20 years).The mean follow-up period was 3.6 years (range,2-8.9 years).The mean preoperative Cobb angles of lumbar and thoracic curve were 44.2° and 25.2°,respectively.At the last follow-up,they were corrected to 10.3° and 13.6°,indicating 75.7％ and 44.9％ correction rate,respectively.The pre-and post-operative mean trunk shifts were 2.2 cm and 2.0 cm with no significant differences.At the last follow-up,it compensated to 0.9 cm,which showed significant differences compared with that of postoperation.Linear regression analysis suggested that trunk shift changes during follow-up period were only correlated with changes of distal unfused segments.The regression equation could be described as Changes of trunk shift (cm) =1.248 7+0.137 8×Changes of distal unfused segments (°).Conclusion The reconstruction of coronal trunk balance is mainly compensated by distal unfused segments after selective posterior correction for thoracolumbar/lumbar idiopathic scoliosis.Although preserved most of its levels,unfused thoracic segments do not play an important role in the reconstruction of trunk shift.