Pedicle screw loosening and axial dislocation are main reasons for spinal internal fixation failure. Screw loosening and dislocation is caused by screw extraction force,and the screw withdrawl force is related to screw diameter,screw thread design,bone density,and operation skills. Withdrawl intensity is increased with screw diameter and length. Pedicle screw stability can be decreased by osteoporosis. For osteoporotic patients,it is difficult to increase screw diameter alone,so polymethyl methacrylate bone cement is used to enhance screw stability and anti-flexion intensity. However,polymerization heat may induce tissue injury,and long-term stay may produce toxicity and exhibit cancerogenesis. Novel additive materials with good biocompatibility such as hydroxyapatite and calcium phosphate bone cement are gradually replacing polymethyl methacrylate bone cement. In addition,screw entrance point,direction and exact location during screw implantation can decrease pullout strength reducation caused by screw re-twisting and improve screw extraction intensity and stability.

Objective To investigate the anti-apoptosis effect of transgiutaminase 2 (TG2)in osteosarcoma cell line MG-63 and to explore the mechanism of inhibiting apoptosis of tumor cells.Methods The TG2-tgrgeted siRNA was designed,and the hypoxia culture model of MG-63 cells was established by a hypoxia incubator and the cells were divided into four groups:normal oxygen group,the cells were cultured under normal oxygen;hypoxia group, the cells were cultured in hypoxic incubators;control siRNA hypoxia group,the cells were cultured in hypoxic incubators after transfection of control siRNA;TG2 siRNA hypoxia group , the cells were cultured in hypoxic incubators after transfection of TG2 siRNA.The expressions of Bax and cytochrome C (Cyt C)and the apoptotic rates were observed at different time (6,12,24,48,and 72 h)after hypoxia culture.Microtiter plate assay was performed to monitor the intracellular TG2 activity.RT-PCR was used to detect the mRNA expressions of TG2 and Bax.The expressions levels of TG2,Bax and Cyt C were observed by immunohistochemical staining and Western blotting method.The apoptotic rates were analyzed using flow cytometry.Results Compared with normal oxygen group,the activity of TG2,the mRNA and protein expression levels of TG2 in hypoxia group and control siRNA hypoxia group were increased remarkably with the prolongation of the hypoxia time (P<0.01);the expression level of Bax protein was decreased significantly (P<0.01 ), but the expression level of Bax mRNA had no significant change (P>0.05);the expression levels of Cyt C protein in cytoplasm and mitochondria and the apoptotic rates had no markedly changes (P>0.05).Compared with hypoxia group and control siRNA hypoxia group,the expression levels of mRNA and protein of TG2 in TG2 siRNA hypoxia group were decreased significantly at different time points (P<0.01);the protein expression levels of Bax and Cyt C in cytoplasm and the apoptotic rates were increased markedly (P<0.01 );the expression level of Cyt C in mitochondria was decreased (P<0.01).Conclusion TG2 can inhibit the apoptosis of tumor cells through down-regulating the Bax expression and preventing Cyt C releasing into the cytoplasm.

Objective To study the role of serum chemokines and their receptors in the pathogenesis of atopic dermatitis(AD).Methods Serum levels of interferon ?-inducible protein-10(IP-10),stromal cell-derived factor-1? (SDF-1?),eotaxin,thymus and activation-regulated chemokine(TARC) as well as macrophage-derived chemokine (MDC) were detected by enzyme-linked immunosor bent assay(ELISA) in 39 patients with AD and 39 normal controls.Meanwhile,chem okine receptors CXCR3,CXCR4,CCR3,CCR4 and CCR5 on peripheral blood CD4+T-lymp hocytes were analyzed by flow cytometry with a two-color immunofluorescent sta ining in 39 patients with AD.Results Serum levels of SDF-1?,TARC and MDC we re significantly higher(P 0.05) between the patients[(123.6 ? 110.4) pg/mL a nd (68.7 ? 26.2) pg/mL,respectively]and controls [(100.7 ? 73.7) pg/mL and(66.8 ? 20.5) pg/mL,respectively].The expression of CXCR3,CCR3,CCR4 and CCR5 o n CD4+T cells was increased (P

目的探讨启蒙教育对提高脑瘫患儿智力和注意力集中能力的作用。方法组织启蒙教育班,对25名脑瘫患儿通过游戏、手工、学儿歌、音乐、辨色、认识方位等多种形式开发智力 ,培养注意力集中能力。结果经启蒙教育后,患儿智商比教育前明显增高(χ2=4.13,P<0.05),注意力集中能力明显增高。结论启蒙教育可提高脑瘫患儿的智力和注意力集中能力,促进患儿的全面康复。

Objective: To investigate the correlation between calcaneal bone mineral density and bone mineral, fat and muscle content in adolescents. Methods: A total of 368 adolescents who received health examination in Hainan People’s Hospital were selected as the study subject. Calcaneal bone mineral density, bone mineral content, fat content and muscle content of adolescents were measured. Bone mineral density and body composition of adolescents of different ages and sexes were compared. The correlation between calcaneal bone mineral density and bone mineral content, fat and muscle content were analyzed. Results: The BUA, muscle mass and bone mineral content of boys were significantly higher than those of girls, and the fat content of boys was significantly lower than that of girls, the differences were of statistical significance(t=13.51, 10.65, 4.52, -7.55, P<0.05). Calcaneal bone mineral density in adolescents was positively correlated with BMI, bone mineral content and muscle mass(r=0.39, 0.42, 0.69, P<0.05). There were significant differences in BUA, BMI, muscle mass and bone mineral content among boys of different ages(F=7.95, 8.63, 6.96, 5.01, P<0.05). There were significant differences in BUA, fat, muscle and bone mineral contents among girls of different age groups(F=8.65, 10.33, 7.96, 4.87, P<0.05). There was no significant correlation between BUA value of calcaneus and BMI and muscle mass in adolescents aged 12, 13-year old(P>0.05), while BUA value of calcaneus in adolescents aged 14-year old, 15-year old and 16-year old was positively correlated with BMI and muscle mass(P<0.05). Conclusion Calcaneal bone mineral density in adolescents is closely related to bone mineral and muscle content, but not to fat content.

A total of 64 patients with lumbar spondylolisthesis were enrolled from Department of Bone Surgery in the People's Hospital of Haian Province between January 2002 and December 2007, including 19 males and 45 females. They aged 26-73 years with a mean of 48.5 years. Their disease course was 1-15 years with a mean of 4 years. All patients complained about the repeated low back pain accompanied with lower limb radiating pain and intermittent claudication (50-300 m). Fifty-nine patients suffered from lumbar spondylolysis, including L3 Ⅰ degree in 3 cases, L4 Ⅰ degree in 31 cases,L4, Ⅱ degree in 13 cases, Ls Ⅰdegree in 9 cases and L5 Ⅱ degree in 3 cases. The remaining 5 cases were present with lumbar degenerative pseudo-spondylolysis. All patients were processed into whole laminectomy for decompression or vertebral canal decompression by fenestration, domestic vertebral internal fixation, reduction and interbody fusion. Fifty-five patients were followed up for an average of 3.1 years whereas 9 patients were lost. According to Steffee clinical effect grading, the curative effect was evaluated as excellent in 28 cases and good in 19 cases, the rate of excellence and good accounted for 85.5%. Within one week following bone graft, all patients were rechecked with X-ray plain film, 28 of them had shown complete reduction and 36 cases were present with part reduction. The fusion rate of interbody graft was 100%. These findings demonstrated that vertebral internal fixation system possesses a simple structure, convenient operation and solid fixation, resets the slipped vertebral body and significantly increases the fusion rate of vertebral graft.

Objective To observe changes in the working memory and brain functional imaging on functional magnetic resonance imaging(fMRI) after 36 hours sleep deprivation (SD) in healthy volunteers and to explore the possible mechanism of the changes.Methods FMRI scannings were performed in ten male healthy young volunteers before and after 36 hours SD and results were analyzed using SPM2 software.Subjects were also tested LTR and PLUS task to measure the persistence and operation of working memory before and after 36 hours SD.Results The reaction time of LTR task after 36 hours SD ( (866 ± 102) ms)was significantly longer than that before SD ( (754 ± 91 ) ms, t = 2.59, P < 0.01 ).The reaction time of PLUS task after SD ( (848 ± 94) ms) was significantly longer ( t = 2.37, P < 0.05 ) than that before SD ( (756 ± 79) ms).The error rate of LTR task after SD (95.3% ± 3.56% ) was significantly higher (t=3.52,P < 0.01 ) than that before SD (84.8% ± 8.71% ).The error rate of PLUS task after SD (95.7% ±4.72% ) was significantly higher (t =3.38 ,P <0.01 ) than that before SD (84.2% ±9.66% ).There were no significant differences between the two tasks.The frontal and parietal lobes, anterior cingulate gyrus and thalamus were activated during memory tasks testing before SD.Brain activation was broader and stronger in PLUS task than in LTR task.After SD, activation in parietal lobe was decreased and activation in prefrontal and thalamus was increased significantly.Conclusions The working memory performance decreased after SD.Both LTR and PLUS tasks of working memory activate frontal and parietal lobes, anterior cingulate gyrus and thalamus.The activation of parietal lobe decreased and the activation of prefrontal lobe and thalamus increased after 36 hours SD.This is the possible mechanism of SD to causes the cognition decline.

Objective To observe any effect of low intensity pulsed ultrasound (LIPUS) on the expression of integrin-focal adhesion kinase (FAK)-mitogen-activated protein kinase (MAPK) mechanochemical transduction pathway-related proteins in the chondrocytes of rabbits with knee osteoarthritis (OA).Methods Of the 18 New Zealand white rabbits selected for the study,twelve received knee anterior cruciate ligament transection to model OA.The remaining 6 rabbits served as normal controls.At the 4th week after modeling the rabbits were sacrificed and chondrocytes were isolated and cultured in vitro.All the cultured cells were randomly divided into three groups:a normal control group (NC),an OA model group (OA) and an OA model plus LIPUS group (OA + LIPUS).When the cells had been cultured to the 2nd passage,the NC group and OA group cells had received no treatment.The OA + LIPUS group cells were exposed to 40 mW/cm2 of LIPUS for 20 min,once a day for 6 days.The expression of collagen protein type Ⅱ,aggrecan,MMP-13,integrin β1 p-FAK and p-p38,p-ERK1/2 and p-JNK Mapks were detected by Western blotting.Results Compared with the NC group,the expression of collagen type Ⅱ and aggrecan was significantly lower in the OA and OA + LIPUS groups,with more significantly lower expression of collagen type Ⅱ and aggrecan in the OA group than in the OA + LIPUS group.Compared with the NC group,the expression of MMP-13 was significantly higher in the OA and OA + LIPUS groups,with a significantly larger increase in the OA group.Compared with the NC group,the expression of integrin β1 and p-FAK was also significantly higher in the OA and OA + LIPUS groups,with a significantly larger increase in the OA + LIPUS group.Compared with the NC group,the expression of p-p38,p-ERK1/2 and p-JNK was also significantly higher in the OA group,but compared with the OA group,the expression of those kinases was,on average,significantly lower in the OA + LIPUS group.Conclusions LIPUS can inhibit the degradation of collagen type Ⅱ and aggrecan,and inhibit the expression of MMP-13,p-p38,p-ERK1/2 and p-JNK in OA chondrocytes,at least in vitro.At the same time,LIPUS can increase the expression of integrin β1 and p-FAK.The results show that LIPUS may activate an integrin-FAK-MAPK mechanochemical transduction pathway to induce changes in the extracellular matrix of chondrocytes.

Objective To investigte the association between haplotype of the promoter of interleukin-22 (IL-22) gene and the susceptibility to pulmonary tuberculosis.Methods Clinical data of 479 patients with pulmonary tuberculosis was collected from Shenzhen Third People's Hospital during January 2009 and December 2010,and 358 healthy controls were also enrolled in the study.Single nucleotide polymorphisms (SNPs) of IL-22 (rs2227472,rs2227473,rs2227478,rs2227483,rs2227485,rs2227486,rs2227487 and rs2227513) were genotyped using the Sequenom MassARRAY iPLEX Platform.The allele frequency and odds ratio (OR) of genotypes of SNPs and haplotypes of IL-22 were calculated; the association between the haplotypes of IL-22 and the susceptibility to pulmonary tuberculosis was analysis.Results rs2227472,rs2227473,rs2227478,rs2227483 and rs2227485 were associated with the susceptibility to tuberculosis (OR =0.796,0.653,0.769,0.762 and 0.816 ; x2 =4.594,6.921,5.256,5.089 and 3.827 ; P ＜0.05 or P ＜ 0.01).The frequencies of haplotypes (CTFAA and TATGG) in case group were significantly different from those in control group (CTFAA:0.004 vs.O.032,OR =0.04,x2 =384.623,P＜0.01; TATGG:0.522 vs.0.460,OR=1.49,x2 =6.690,P=0.01).Conclusions Five SNPs of IL-22 (rs2227472,rs2227473,rs2227478,rs2227483,rs2227485) and 2 haplotypes (CTTAA and TATGG) are associated with the susceptibility to pulmonary tuberculosis.Haplotype CTTAA is a protective factor for susceptibility to pulmonary tuberculosis,whereas haplotype TATGG is a risk factor.

Objective To observe the effect of low intensity pulsed ultrasound (LIPUS) on chondrocytes co-cultured with infrapatellar fat pads.Methods Twenty-four infrapatellar fat pads and cartilages from female knee trauma patients aged between 25 and 35 were cut and stained using hematoxylin-eosin staining.Chondrocytes were isolated from part of the integrated surface of the cartilages to be cultured in vitro.They were then randomly divided into a normal chondrocyte group (the control group),a normal chondrocyte+FCM (fat conditioned medium) group (the model group),a normal chondrocyte+ FCM + LIP US group (the treatment group),and a normal chondrocyte+ FCM + LIPUS + GRGDSP (an integrin inhibitor) group (the inhibited group).The treatment group and inhibited group received LIPUS at 40 mW/cm2 for 20 min once a day,while the other groups received sham LIPUS treatment.Five days later,the cells were collected and western blotting was used to examine the expression of type Ⅱ collagen (COL2),aggrecan (Acan),matrixmetalloproteinase (MMP)-13,integrin β1,phosphorylation-focal adhesion kinase (p-FAK) and phosphorylation p38 (p-p38).Results Western blotting showed that compared with the control group,the expression of COL2 and Acan was significantly lower in the model group,but that of MMP-13,integrin β1,p-FAK and p-p38 was significantly higher.As compared with the model group,the expression of COL2,Acan,integrin β1 and p-FAK was significantly higher,and that of MMP-13 and p-p38 was significantly lower in the treatment group.The expression of COL2,Acan,MMP-13,integrin β1,p-FAK and p-p38 showed no significant difference between the inhibited and model groups,but that of COL2,Acan,MMP-13,integrin β1,p-FAK and p-p38 was significantly different between the control and treatment groups.Conclusions LIPUS provides a protective effect on chondrocytes through inhibiting the expression of MMP-13 induced by adipokines and the degradation of COL2 and Acan through activating the integrin-FAK-p38 MAPK pathway.