BACKGROUND:With the improvement of cervical posterior surgical techniques, lateral mass screw fixation technology has been widely used in the reconstruction surgery of the cervical spine for stability. However, currently, the finite element study on the lateral mass screw fixation reconstruction of the cervical spine is rare. OBJECTIVE:To establish a fine normal lower cervical spine (C3-C7 ) three-dimensional finite element model and a reconstructed finite element model with three-segment laminectomy with lateral mass screw fixation. Then, to do an initial biomechanical analysis of the lateral mass screw fixation reconstructed lower cervical finite element model. METHODS:We col ected a normal female volunteer aged 30 years old to do CT scan for the whole cervical spine. The Dicom data were obtained. Then, the CT scanning images were dealt with software Mimics 10.01, Geomagic Studio 12.0, Solidworks2012, HyperMesh 10.1 and Abaqus 6.12 software to build the normal lower cervical spine (C 3-C7 ) finite element model, the laminectomy finite element model and the rebuilt finite element model. At last, we analyzed the stress changes of reconstructed models under the state of flexion, extension, lateral bending and rotational motion. RESULTS AND CONCLUSION:The lower cervical spine finite element model contained 503 911 elements and 93 390 nodes with a fine realistic appearance. It successful y passed the validation. The surgical procedure was completed in the software, and the lateral mass screw fixation reconstruction finite element model has been established. Lateral mass screw fixation system provides good stability for the postoperative finite element model. The activity of rebuilt finite element model is much lower than the normal finite element model. In the extension condition, the stress of lateral mass screw fixation system becomes strong.

Objective To study the role of water exact from salvia miltiorrhiza (SM) in promoting hair regrowth in testosterone (T)-induced alopecia in mice.Methods Pathological alopecia mice were induced by T and the mice were randomly divided into control group,model group,Zhanggvanp 101 group,SM low-dose group,SM middle-dose group,SM high-dose group (20,40,80 mg/ml,respectively).The effects of SM on hair regrowth were evaluated by measuring hair length,weight and the number of hair follicle.The concentration of serum T and estrodiol (E2),the content of skin VEGF,MDA,SOD,and GSH-Px were measured after external inunctum for 21 days.Results (1) SM significantly promoted regrowth hair length,weight and the number of hair follicle (P＜0.05) (2) SM significantly balanced the hormones by reducing levels of T and increasing E2 (P＜0.05) (3) SM significantly reduced the content of MDA by increasing the activity of SOD and GSH-Px (P＜0.05) (4) SM significantly increased the level of VEGF (P＜0.05) Conclusion In the pathological alopecia mice induced by T,SM can effectively promote the hair regrowth,with the possible mechanism of balancing hormones,being anti-oxidant and improving VEGF expression.

Objective To assess the effect and influencing factors on 131I treatment for cervical lymph node metastasis (LNM) after operation in patients with PTC.Methods PTC patients (n =117;45 males,72 females;average age (45.17± 15.50) years) with postoperative cervical LNM from January 2010 to December 2014 were analyzed retrospectively.LNM was diagnosed by surgical pathology,imaging results and clinical follow-up.Single factor analysis was performed in age,gender,operation mode,TNM stage,131I treatment time and other factors.The results for 131I treatment effect included CR,PR,NC.Two-sample t test and x2 test were used.Results Among the 117 PTC patients with postoperative LNM,53 (45.3％) cases had non-131 I-avid metastasis.Fifty of the 64 (54.7％) patients with 131I-avid metastasis were treated with 131I.Nineteen patients (38.0％) achieved CR,22 (44.0％) achieved PR,and 9 (18.0％) showed invalid results.Fourteen of the 64 patients underwent another cervical lymph node dissection.Nine patients achieved CR,5 patients achieved PR,and 4 PR patients were then treated with 131I and finally achieved CR.Single factor analysis showed that the influencing factors of non-131I-avid lymph node included patients' age (t =3.459),serum Tg level (x2 =6.698) and metastasis with 1s F-FDG uptake (x2 =26.928;all P＜0.05).The influencing factors of 131I treatment effect included lymph node dissection procedure (x2 =6.487),unilateral or bilateral lesion (x2=5.187) and LNM size (x2=8.099;all P＜0.05).Conclusions 131I treatment is ineffective for nearly 50％ of patients with non-131I-avid LNM.The influencing factors of 131I treatment effect include the lymph node dissection procedure,unilateral or bilateral lesions and LNM size.

Objective To analyze and evaluate the efficay of split liver transplantation in children.Method From September 2006 to December 2014,210 children were treated with liver transplantation in Tianjin First Central Hospital.The clinical data were retrospectively analyzed and the difference in postoperative survival was compared between the groups.The 210 childrens were categorized into living donor liver transplantation group (183 cases) and split liver transplantation group (27 cases) based on their operation styles.In living group,all donors to recipients were immediate relatives within three generations.In split group,all donors were men,and livers were obtained from no heartbeat donors.Postoperatively,tacrolimus combined a duplex of prednisolone served as immunosuppression scheme.The survival and incidence of complications were observed.Result There was significant difference in the sex ratio between two groups (P＜0.05).The donor liver cold ischemia time was significantly longer in split group than in living group (P＜0.05).The 1-month,6-month,1-year and 2-year overall survival rate in 210 recipients was 99.5％,98.1％,96.2％ and 94.2％ respectively.The median follow-up time in living group and split group was 15.2months and 26.1 months,respectively.The 1-mont,6-month,1-year and 2-year survival rate was 99.5％,96.7％,92.6％ and 74.1 ％ in living group,and 97.8％,96.2％,77.8％ and 74.0％ in split group,respectively (P＜0.05).During the follow-up period,8 cases died (29.6％) in split group (5deaths due to infection and sepsis,and 3 deaths due to multiple organ failure),and 10 cases died (5.5％) in living group (6 deaths due to infection and sepsis,and 4 deaths due to multiple organ failure).Conclusion In the case of strict selection of donors,split liver transplantation can obtain good effect,but the incidence of complications is higher than living donor liver transplantation.Especially,the biliary complications should be prevented and managed actively.

A comprehensive analytical method based on ultra performance liquid chromatography tandem mass spectrometry has been developed for the simultaneous determination of 16 carcinogenic and allergenous dye stuffs (acid red 26, basic red 9, disperse blue 1, acid violet 49, disperse blue 3, solvent yellow 1, dispersed blue 106, disperse orange 3, disperse yellow 3, basic violet 1, basic violet 3, disperse red 1, solvent yellow 3, disperse blue 124, solvent yellow 2 and disperse orange 37).Various toy samples, including textile, leath er, paper, wood, balloon, modeling clay, limitation tattoo and aqueous liquid, were extracted under ultrason ication.Qualitative and quantitative analysis was carried out for the analyte under the MRM mode after the chromatographic separation on Waters ACQUITY UPLC BEH C_(18)(50 mm x 2.1 mm, 1.7 μm) column.The limits of quantitation(LOQ) for the 16 dyestuffs were in the range of 1.0-8.0 μg/kg.The mean recoveries at the three spiked levels of 5-100 μg/kg were 81.3%-98.6%, with the intra-day precision less than 11% and the inter-day precision less than 14%.The method is accurate, rapid, sensitive, and adapt to the inspec tion of the 16 dyestuffs in toys.

Objective To study whether abnormalities can be detected by MR diffusion tensor imaging (DTI) technology in radiologically isolated syndrome (RIS) patients with normal-appearing white matter (NAWM).Methods Twenty-seven patients who met diagnostic criteria for RIS were collected.Sixteen age-and sex-matched healthy controls with normal neurologic examination findings and no history of neurologic or psychopathic disorders were included.All subjects were examined by both conventional scan and DTI scan on GE Signa 3.0 T MRI.All the images were transmitted to the Advantage Workstation 4.2P and postprocessed using functool software.Anisotropic maps and average diffusion coefficient (ADC) maps were reconstructed.Two ROIs were selected in the genu and splenium of the corpus callosum separately at the trigone of lateral ventricle level.Other 2 ROIs were selected in the anterior and posterior body of the corpus callosum separately at the level of the lateral ventricle body,and 1 ROI was selected in the white matter of bilateral frontal and occipital lobe separately,then the FA and MD values were measured.The diffusion indices (FA and MD)were analysed by SPSS 13.0.Independent-sample t test was performed to examine the group differences in each subregion.Intraclass correlation coefficient analysis was performed to assess the diffusion indices of two measurements in each subregion.Results The ICC of 2 measurements was 0.934-0.989 (P ＜ 0.01),which showed favorable consistency.The FA values were decreased obviously in the genu,anterior and posterior body of the corpus callosum of the RIS patients compared with controls (0.705 ±0.040 vs 0.738 ±0.045,0.632 ±0.043 vs 0.675 ±0.042,0.628 ±0.043 vs 0.666 ± 0.045,t =-3.526,-4.487,-3.890,P ＜0.01),but the FA values of the two groups did not show any significant difference in the splenium,the white matter of the frontal and occipital lobe respectively (t =-1.387,-0.683,-1.243,P ＞0.05).In comparison with controls,the RIS patients had increased MD values in the genu,anterior and posterior body of the corpus callosum.(0.891 ±0.038 vs 0.874 ±0.035,0.839 ± 0.047 vs 0.794 ± 0.031,0.833 ± 0.039 vs 0.792 ± 0.057,t =2.101,5.836,5.146,P ＜ 0.05),but the MD values of the two groups did not show any significant difference in the splenium,the white matter of the frontal and occipital lobe respectively (t =1.671,1.702,1.624,P ＞ 0.05).Conclusion The NAWM abnormalities in the patients with radiologically isolated syndrome could be detected by DTI.

Objective To evaluate the safety and clinical effect of ABO-incompatible (ILT) pediatric living donor liver transplantation.Method We analyzed 169 pediatric living donor liver transplantation recipients from Sept.20,2006 to Dec.31,2014.There were 16 ABO-incompatible liver transplantation cases.The median age was 6 months.The blood agglutitin titer was monitored.The titer was controlled lower or equal to 1 ∶ 16.The method to decrease blood agglutitin titer included IVIG and plasma exchange.The patients were treated with Tacrolimus combined with methylprednisolone.Basiliximab for injection was used.The patients were followed-up for 9-26months.The survival rate,acute rejection,vascular and biliary tract complications,and infection were monitored.Result All the patients survived.There was once case of acute rejection,1 case of bile duct dilatation,2 cases of portal vein stenosis,8 cases of EBV viremia,5 cases of CMV viremia,and 6 cases of lung infection.The liver functions of all the 16 recipients were recovered within 3 weeks.Conclusion ABO-incompatible liver grafts can be used safely in pediatric patients.

Objective To identify the long-term survival of patients with hepatic carcinoma who received hepatitis B surface antigen (HBsAg) positive donor livers.Method A total of 195 patients were enrolled in the study.They were all diagnosed as having hepatic carcinoma with malignant thrombus in portal vein pre-operation and received liver transplantations between 1999 and 2014.The long-term survival between the patients who received HBsAg positive grafts and those who received HBsAg negative grafts was compared.Result There were no differences in ages,preoperative tumor stages and postoperative mortality between the two groups.There was significant difference in survival time between the two groups (Z=-2.038,P =0.042),with the median survival time of 8.83 months (2.50-24.80 months) in HBsAg positive graft group and 13.12 months (6.50-27.65 months) in HBsAg negative graft group,respectively.The long-term survival rate in HBsAg positive graft group was 48％ and that in HBsAg negative graft group was 34.7％ (P =0.740,x2 =0.110).However,the proportion of deaths due to recurrence of tumor was high to 75.8％ in all causes.Conclusion To prolong the survival time,it is safe and feasible to receive HBsAg positive donor livers in patients with hepatic carcinoma in late stage.However,tumor recurrence was still the main causes of deaths in patients post-operation because of the advanced tumor conditions pre-operation.

Objective To investigate the clinical characteristics,treatment and prognosis of single-system Langerhans cell histiocytosis (LCH) in children.Methods A retrospective analysis was performed in single-system LCH patients registered between January 2006 and December 2012 in Beijing Children＇s Hospital Affiliated to Capital Medical University.The patients were divided into 2 groups:the bone involvement group and the other organ involvement group.The patients were assessed at 5 weeks,11 weeks,25 weeks,3 months,6 months,1 year and 3 years.The data were analyzed by using SPSS 17.0 software.Results A total of 112 patients (66 boys and 4,6 girls) with a median age of 5 years at diagnosis of LCH were analyzed.The most frequently affected organ was the bones(91 cases,81.3％),followed by skin(15 cases,13.4％).Few patients (27.6％) had acentral nervous system risk lesion,who were younger than those with other bone lesion(2.5 years vs 6.6 years).Patients with bone lesions were diagnosed at a significantly older age than other patients(5.6 years vs 1.5 years) (P ＜ 0.01).All patients received chemotherapy that included Prednisone and Vinblastine for 25 weeks.Twenty-five patients (22.3 ％) showed reactivation.Of these,4 patients exhibited reactivation in the pituitary.Three-year overall survival rate was expected to reach 100％,and no-event survival was expected at (73.22 ± 4.47) ％.Age of less than 2 years old was the factor of reactivation (P =0.033);sex,organ involvement and member of bone involved were not related with reactivation (P =0.679,0.142,0.639).Conclusions The bones were the frequent involvement organ in single-system LCH patients.These patients have a good prognosis.The rate of reactivation of single system-LCH can be decreased by chemotherapy.

To investigate the value of MRI for the diagnosis of achilles tendon closed rupture. 1.5T Maestro Class MRI scanner was used for the conventional scanning of 15 patients confirmed with achilles tendon closed ruptures by operation, and then the findings by imaging were compared with those by operation. The 15 patients proved with achilles tendon closed rupture, including 4 cases of incomplete rupture and 11 cases of complete rupture. MRI could display clearly the changes in morphology and signal of incomplete or complete closed ruptures of Achilles tendon, and the results were consistent with those by operation. MRI can make an accurate display of the lo-cation and extent of achilles tendon rupture.