Stem cell is one of the hot spot in the research area of biomedical engineering. Special attentions are drawn to the research and application of neural stem cells. Neural stem cells exist widely in central nervous system, which has the capacity of self-renewal and the potential to differentiate into other cells. The so-called engineered neural stem cell is constructed by using the technique of genetic engineering to make it be able to express various neural growth factors with high-performance and stability. The engineered neural stem cells have a great potential in the therapy of diseases of central nervous system, especially the spinal cord injury. This article reviews the research development of engineered neural stem cells, the problems confronted with it, and the trend for research in the future.

The nerve tissue engineering is to apply scalfolds and seed cells for the treatment of injury or disease of nerve system by restoring their anatomic structures and funetiorm.The scaffolds played important roles in supporting and conducting axonal regeneration.They could also limit the in-growth of scar tissue and hence help to build the connection between axonal and target cell.Self-assembling peptide scaffold is one of the excellent material used is nerve tissue engineering.This article reviews the self-assembling peptide based scaffolds for nerve tissue engineering and discusses the unsolved problems in the fields and the trend d the related research in the future.

Aim To explore the effects of tetrameth-ylpyrazine-2′-O-sodium ferulate (TSF)on the swelling of
astrocytes and the expression of AQP4 after oxygen gl-ucose deprivatio /reoxygenation(OGD /Reox).Methods
Astrocytes were divided into 4 groups:control group, OGD /Reox group,Ozagrel group and TSF group.The effects of TSF on astrocytes were investigated 6,1 2,24 and 48 h after OGD /Reox.The cell injury was assessed by measuring LDH activity and MTT.The expression levels of AQP4 protein of astrocytes were detected u-sing Western blot.Results OGD /Reox induced obvi-ous cell swelling and significant reduction of LDH in astrocytes whereas TSF remarkably attenuated OGD-in-duced astrocyte swelling and LDH reduction (P <0.01 ).The expression levels of AQP4 protein in-creased gradually to the peak at 48 h in OGD /Reox
group(P <0.05 ).AQP4 protein levels in TSF group were much lower compared with OGD /Reox group at each time point (P <0.05).And there was no signifi-cant difference between TSF group and OGD /Reox group(P >0.05 ).Conclusion TSF can attenuate OGD-induced swelling of astrocytes through decreasing the AQP4 expression.

1000 ml per day had to be cured by operation.

Objective To analyse the CT features of pulmonary echinococcosis and to assess CT value in diagnosing this disease.Methods CT fingings of pulmonary echinococcosis in 35 cases proved pathologically were analyzed retrospectively.Results Pulmonary granulosus echinococcosis was 33 cases including simple hydatid cyst (11 lesions),datugter cyst hydatid (3 lesions),with calcification (1 lesion) ,rupture (11 lesions),merging infection (4 lesions) and rupture into thorax (3 lesions).Pulmonary alveolar echinococcosis was 2 lesions,CT findings apperared as irregular,peripherally scattered more nodules with small vacuoles or calcification and in combination with hepatic alveolar echinococcosis.Conclusion Pulmonary echinococcosis had characteristic features on CT,CT examination can provide more imaging informations for the treatment of pulmonary echinococcosis

Objective: To explore the mechanism of damaging effect of advanced glycation end products (AGEs) on human umbilical vein endothelial cell (HUVEC) in vitro. Methods: The HUVEC was incubated with exogenous AGEs for 12 h, and ergamine (Hi) and catalase (CAT) were used as control. The activity, monolayer permeability, apoptosis rate, biochemical indexes and morphous changes were detected in HUVEC. Results: The activities of HUVEC were dose-dependently reduced by exogenous AGEs(40 mg/L, 120 mg/L and 160 mg/L), meanwhile the monolayer permeability, the malondialdehyde (MDA) content and apoptosis rate were increased，the activity of superoxide dismutase（SOD）was decreased（P < 0.05, respectively). There was no significant difference in damaging effect between exogenous AGEs and Hi(P ＞ 0.05). The damaging effect of exogenous AGEs was obviously inhibited by CAT in HUVEC. Conclusion: Exogenous AGEs induced the damaging effect on vascular endothelial cells, which may be related to the oxidative stress.

Objective To investigate the effects of cryopreservation on the growth and osteogenesis capa- bility of human bone marrow stromal cells(BMSCs)on demineralized bene matrix(DBM).Methods Bone marrow aspirates were obtained from the lilac crests of three donors.The BMSCs were isolated from the bone marrow by density gradient centrifugation.Cells of passage 3 were cryopreserved in liquid nitrogen for 24 hours,and then re- covered.The non-cryopreserved BMSCs were used as the control,The cryopreserved and control BMSCs were cul- tured in osteogenic media,collected and labeled with Dil to be seeded onto the DBM when cells were confluent.The percentage of BMSCs adhered to the DMB was detected.The cell morphology and matrices secreted by BMSCs on the DBM were observed by the inverted phase-contrasted microscope,fluorescence microscope and scanning electron microscope(SEM).The growth and viability of BMSCs on the DBM were determined using the modified MTT ashy. The osteogenesis ability of BMSCs on the DBM was determined by assessment of the alkaline phosphatase(ALP) activity and osteocalcin(OCN)content.Results The percentages of the cryopreserved and control cells adhered to DBM were(97.25?1.17)% and(97.00?1.09)% respectively.The cells adhered well to the DBM and grew rapidly.Large amounts of matrices on the DBM were observed by the light microscope and SEM.The cells embedded in the matrices could be observed by fluorescence microscope.There were no significant differences in the assay values of MTT,ALP and OCN between the cryopreserved and control BMSCs on the DBM.Conclusion Since cryopreservation does not affect the growth and osteogenesis capability of BMSCs on DBM,the cryopreserved BMSCs can be used as a cell source in bone tissue engineering.

Objective To compare the clinical outcome between vertebra fracture fixation plus injectable calcium sulfate vertebroplasty and simple vertebra fracture fixation in the treatment of thoracolumbar burst fracture.Methods A total of 61 patients with thoracolumbar burst fracture treated from January 2005 to December 2008 were involved and divided into two groups,ie,Group A ( treated with three-level fixation at fractured vertebra and injectable calcium sulfate vertebroplasty) and Group B ( treated with three-level fixation at fractured vertebra alone).Group A had 22 males and 10 females,at mean age of 36.8 years (21-65 years).The mean follow-up period was 15.6 months (13-27 months).Group B had 18 males and 11 females,at mean age of 38.3 years (19-70 years).The mean follow-up period was 14.7 months (12-28 months).The ratio of anterior vertebral height,Cobb angle,VAS score were compared between the two groups.Results There were no statistical differences in the aspects of age,sex,fracture segments and preoperative neurological status distribution in the two groups( P ＞0.05 ).All patients with partial neurologic deficits initially improved for 1-2 grade at the final follow-up.Blood loss and operation time in Group A were less than that in Group B (P ＜0.05 ).The ratio of anterior vertebral height and the Cobb angle showed no statistical significance (P ＞ 0.05 ),but the ratio of anterior vertebral height and the Cobb angle in Group A was less than those in Group B at the latest follow-up (P ＜0.05 ).The VAS score showed no statistical significance between the two groups at the latest followup (P ＞ 0.05 ).There was one patient with screw breakage in Group B,while there was no implant failure in Group A.Conclusion The vertebra fracture fixation plus calcium sulfate cement vertebroplasty is a safe and effective method for the treatment of thoracolumbar burst fracture as it can restore the vertebral mechanical strength,achieve and maintain kyphosis correction,decrease the instrument failure rate and loss of vertebral height.

Objective To evaluate the feasibility and outcome of transpedicular screw fixation in fracture reduction and maintenance of reduction for thoracolumbar fractures.Methods The clinical data of 43 patients with thoracolumbar fractures admitted to Orthopedic Trauma Hospital of Qingdao from January 2003 to December 2006 were retrospectively analyzed.The inclusion criteria were as follow;sin-gle vertebral fracture involving T_(12)-L_2, integrated pedicle and no inferior endplate fracture.All patients received operation within 10 days after injury.Three-level fixation at fractured vertebra plus pedicle screw fixation was performed in 23 patients (Group A) including 15 males and 8 females, at mean age of 45 years (19-77 years).Traditional two-level fixation was done on the other 20 patients (Group B) inclu-ding 11 males and 9 females, at mean age of 42 years (22-67 years).In Group A, the transpedicular screws fixing the fractured vertebra and cephal vertebra were distracted after locking the transpedicular screw of the fracture vertebra and caudal vertebra.Results The height of the anterior edge of the cau-dal disc in Group B was 0.035 ±0.042, greater than 0.061 ±.036 in Group A, with statistical differ-ence (P < 0.05).There was no statistical difference in the changes of Cobb angle after the operation be-tween (915.8 ±7.8)°in Group A and (13.1±5.2)°in Group B.34 patients were followed up for an average period of 15 months (11-24 months) , which showed smaller Cobb angle in Group A (5.4°compared with Group B (8.9°)(P <0.05).There was one patient with screw breakage in Group A and two in Group B.Conclusion Transpedicular screws can enhance the stability of the posterior short-segment instrumentation, avoid over-distraction of the caudal discs, improve stress distribution and lessen loss of correction for some thoracolumbar fractures.

Objective To analyse the effect of dual-antiplatelet drugs on S100β,IL-1β, adiponectin(ADPN)and NIHSS score in patients with acute cerebral infarction.Methods 58 patients diagnosed with acute cerebral infarction in first hospital of Qinhuangdao.All patients were collected and randomly divided into experimental group and control group according to random number table , 29 cases in each group.Both group were given the treatrnent of improvng the cerebral vascular circulation, protect brain cells, control blood pressure, blood glucose, oxygen when necessary.On the basis of conventional treatment, control group was treated with aspirin 200 mg, one time per day,orally.And experimental group was treated with clopidogrel 75 mg/d on the basis of control group,one time per day,orally.After treatment, the serum levels of S100β, IL-1β, ADPN and NIHSS score were detected in all patients.ResuIts After treatment, compared with control group,the serum S100βprotein level was significantly lower in the experimental group (P<0.05); the serum IL-1βlevel in experimental group was significantly lower (P<0.05);ADPN level in experimental group was significantly higher (P<0.05); NIHSS score of patients in experimental group was significantly lower (P<0.05).ConcIusions Dual antiplatelet drugs can reduce serum S100βprotein,IL-1βin serum of patients with acute cerebral infarction, increase the level of serum adiponectin, decrease NIHSS score, can effectively improre neurological function in patients with acute cerebral infarction.