Objective Construct the finite element model of vertebral pedicle screw fixation in thoracolumbar fractures can obtain the intuitive systematic mechanical effects under different motion conditions, it has a very important significance to the patients' rehabilitation, evaluation of system stability and prognosis.In this study, the biomechanical effects of different motion states of thoracic and lumbar spine fracture models were analyzed by the finite element analysis method.Methods We selected 1 orthopedic health volunteers from Nanjing General Hospital of Nanjing Military Region in June 2014, established the finite element model by the CT scan data of the healthy volunteer, used the geometric cutting method for fracture simulation and replacement, assembled posterior orthopedic internal fixation system of vertebral pedicle screw, simulated the different motion states and obtained the stress nephogram and displacement graph of the nail-stick system..Results For the six-nail and two-rod internal fixation system of posterior nail-stick system which set nails through injured vertebrae, we used the finite element operation method to simulate the biomechanical characteristics of different modes of motion in space, it combined by the movement of six directions(flexion, dorsiflexion, left side bend, right side bend, left twist, right twist).The maximum stress(94.99±1.72MPa) and the maximum displacement(0.1854±0.0052mm) and the of the dorsiflexion were significantly lower than that of flexion[(126.82±5.56)MPa、(0.2502±0.0050)mm]、left side bend[(152.18±9.13)Mpa、(0.3172±0.0048)mm]、right side bend[(159.58±13.54)Mpa、(0.3315±0.0051)mm](P<0.05).Conclusion The method of finite element analysis can obtain clear and intuitive biomechanical data, which provides effective evidence for the evaluation of surgical efficacy, the development of postoperative rehabilitation methods and the evaluation of the stability of thoracolumbar spinal system.

Objective:To analyze risk factors that were associated with loss of correction curvature after short-segment restoration and fixation in cases who had single-segment thoracolumbar fracture.Methods:87 Cases who had experienced single-segment thoracolumbar fracture and had underwent short-segment restoration and fixation in our department from Jan 2008 to Jan 2011,and had complete follow-up imaging were included.Cobb angles were measured on lateral thoracolumbar X-ray preoperatively,postoperatively and before removal of internal fixation.And these included the angle formed by vertebras that located above and below injured vertebrae (α angle),superior endplate of injured vertebrae and its superior vertebrae (β angle),inferior endplate of injured vertebrae and its inferior vertebrae (γ angle),inferior and superior endplate of injured vertebrae (δ angle).T-test was used to analyze these angles and their changes.And correlation analysis was used to analyze relationships between α angle change and other risk factors.Results:When compared with preoperative angles,the mean α angle,β angle,γ angle and δ angle were all significantly increased (p＜0.05) after the operation.The mean α angle and δ angle before the removal of internal fixation were both significantly smaller than those after the operation (p＜0.05),and the mean change ofα angle was-2.85 degrees.After the correlation analysis,we found significant correlations between the change ofα angle and postoperative correction curvature(-0.342,p=0.026),injured region in endplate(0.374,p=0.015),and change of the δ angle(0.231,p=0.041).Conclusion:There was significant loss in the correction curvature before the removal of internal fixation.And the loss was significantly associated with postoperative correction curvature,injured region in endplate,and change of the δ angle.

Aim To prepare and characterize a monoclonal antibody against recombinant glutathione S-transferase(GST) for purifying GST fusion protein. Methods The GST-follistatin fusion protein was expressed by using a pGEX4T-1 expression vector in Escherichia coli BL21 and purified by glutathione-resin affinity column chromatography. Then female Balb/c mice were immunized with the GST-FS, The immunized splenocytes were fused with NS-1 hybridoma cells. Dreparation of the mAb was used by conventional hybridoma techniqal. The mAb purified by protein A, was culpled with Sepharose4B to purify further GST fusion protein by affinity chromatography. Results The SDS-PAGE showed that the GST fusion protein could be purified effctively by specific mAb affinity chromatography as same as by glutathione-resin affinity chromatography. Conclusion mAb affinity chromatography will be a ecnomical and useful method and it can be used for secondary purification of GST fusion protein following glutathione-resin affinity chromatography.

Objective:To investigate the characteristics of the sleep quality and health-related quality of life (HRQoL), and analyze the different effects of sleep quality on HRQoL among young and middle-aged people.Methods:A cross-sectional study recruited 1 976 participants.All participants completed a self-designed questionnaire for the adults' general condition, the Pittsburgh sleep quality index (PSQI) and Short-Form health survey (SF-36). All participants were divided into 3 age groups: 18-29-year-old group( n=1 148), 30-44-year-old group( n=586) and 45-59-year-old group ( n=242). SPSS 23.0 software was used for statistical analysis.Chi-square test was used to analyze the general characteristics of the three age groups.Non-parametric test was used to analyze the scores of the three age groups in different dimensions of sleep quality. One-way ANOVA was used to analyze the mean scores of the three age groups in different dimensions of HRQoL. Stepwise regression analysis was used to analyze the effect of sleep quality on HRQoL among the three groups after control the confounding factors such as marital status, education, smoking, drinking and exercise habits and past medical history. Results:In terms of sleep quality, the total PSQI scores of 18-29-year-old, 30-44-year-old and 45-59-year-old groups(4(2, 6), 4(2, 6), 4(2, 6)) showed statistically significant differences ( Z=10.951, P=0.004). In terms of HRQoL, there were statistically significant differences in physical component summary scores (18-29-year-old: 82.51±12.62, 30-44-year-old: 80.72±13.63, 45-59-year-old: 82.04±13.07, F=3.667, P=0.026) and mental component summary scores(18-29-year-old: 76.09±15.46, 30-44-year-old: 77.20±16.14, 45-59-year-old: 81.82±14.14, F=13.649, P<0.001) among young and middle-aged people in different age groups.Regression analysis found that daytime dysfunction was an independent influencing factor for HRQoL in young and middle-aged population ( β=-0.308--0.425, all P<0.01). Sleep disorders significantly decreased Physical Component Summary of HRQoL in young-aged people ( β=-0.127--0.215, all P<0.01). The use of hypnotic drugs significantly reduced the scores in the physiological field in the young adults aged 30-44 ( β=-0.076, P<0.05). The duration of sleep significantly decreased the scores in the mental domain of young adults aged 30-44 ( β=-0.112, P<0.01). Subjective sleep quality was an independent factor that significantly decreased HRQoL in young adults aged 18-29 and 30-44 years ( β=-0.089--0.169, all P<0.01). Conclusion:Sleep quality and HRQoL of young and middle-aged people in different age groups show different characteristics.The effect of sleep quality on HRQoL is different among people in different ages.Taking targeted interventions for people of different ages to improve the sleep quality may be an effective way to improve their HRQoL.

Objective:To investigate the effect of interleukin-1β (IL-1β) on epithelial-mesenchymal transition (EMT) and cytoskeleton rearrangement of renal tubular epithelial cells.Methods:Immortalized renal tubular epithelial cell line NRK52E was cultured in vitro with IL-1β (30 μg/L) for 3 days and 6 days,then the cell morphology was observed;The mRNA expressions of α-smooth muscle actin (α-SMA),cytoskeleton components β-actin and α-tubulin were semi-quantitative examined by RT-PCR.The protein expression of α-SMA and arrangements of β-actin and α-tubulin were assessed by immunofluorescent staining.Results:After induced by IL-1β for 3 days and 6 days in vitro,the mRNA and protein expression of α-SMA increased significantly compared with corresponding control cells (P<0.001),it prompted that NRK52E cells underwent EMT;At the same time,the cell morphology also changed,from a typical multilateral paving stone to fibroblast-like appearance,with multiple processes; Cytoskeletal protein β-actin mRNA expression was also slightly increased (P<0.05).The distributions and arrangements of β-actin protein were also changed,from cell membrane transferred to peri-nucleus and cytoplasm,moreover it formed fiber bundle-like structures.However,another cytoskeleton protein α-tubulin in IL-1β induced cells,neither it's mRNA expression nor it's distribution had significant differences compared with the control group.Conclusion:IL-1β can induce NRK52E cells undergoing EMT in vitro,cell morphology changes into fibroblast-like appearance with multiple processes,and also the cytoskeleton protein β-actin expression increases and rearrangement occurrs.However,there was no changes onα-tubulin.

BACKGROUND: Transplantation of bone marrow mesenchymal stem cells (MSCs) has been used in the field of repair of nerve injury. Brain stereotactic transplantation and transvascular transplantation are two transplantation methods. OBJECTIVE: We infused MSCs into rat peripheral cerebral infarct focus, in order to investigate the improvement of rat neurological dysfunction by forelimb use asymmetry test and postural reflex test.DESIGN: A randomized controlled animal experiment. SETTING: Department of Neurology, First Hospital of Jilin University.MATERIALS: This study was performed at the Key Laboratory of Zoonosis, Ministry of Education, Institute of Zoonosis, Jilin University between October 2006 and April 2007. Healthy male Wistar rats of clean grade, weighing 250-280 g, were provided by the Laboratory Animal Center of Jilin University. The protocol was performed in accordance with ethical guidelines for the use and care of animals.METHODS: MSCs from healthy adult volunteers were in vitro cultured and proliferated by density gradient separation and adherence screening method. Their immunophenotypes were identified by a flow cytometer. The Wistar rats were randomized into 5 groups with 10 rats in each: normal control group, sham-operated group, model group, serum-free DMEM-treated group (DMEM group) and MSCs -treated group (MSCs group). Rat models of cerebral ischemia/reperfusion were developed by occluding rat right middle cerebral artery following suture occlusion method modified by Longa et al. Rats in the normal control group were untouched. In the sham-operated group, operation was not ended till cervical interior and exterior arteries were exposed and sutured, and the other disposals were the same as those in the model group. At ischemia 90 minutes reperfusion 1 hour, a stereotaxic apparatus was used to take rat right peripheral cerebral ischemic region as transplantation site: 3 mm lateral to, 1mm caudal to and 4 mm posterior to Bregma. Rats in the MSCs group were slowly injected 5 μL BrdU-labeled MSCs (4×1011 L-1) serum-free medium. Rats in the DMEM group were injected 5 μL serum-free medium. After perfusion, inserted needle was retained for 5 minutes and then slowly withdrawn in order to avoid the back flow of liquid from needle pole. The survival of MSCs in rats was detected by immunohistochemical technique, and rat behavioral changes of observed on days1, 3, 7 and 28 after transplantation by forelimb use asymmetry test and postural reflex test.MAIN OUTCOME MEASURES: ① The immunophenotype of MSCs were identified by a flow cytometer. ② The survival of transplanted MSCs in the rat brain. ③ Rat behavioral changes. RESULTS: All the 50 rats were included in the final analysis. ① High purity of MSCs were harvested in the experiment. Flow cytometer detection showed that both CD44 and CD29 were positive, while CD34, CD45 and CD31 were negative. ② MSCs transplanted into the brains of rats in the MSCs group gathered in the peripheral cerebral ischemic region and survived. ③ Behavioral scores of rats in the MSCs group were significantly lower than those in the other groups (P < 0.05). They were gradually decreased with time after transplantation, and reached the valley value on day 7 after transplantation (P < 0.01). CONCLUSION: Neurological function of rats recovers in all the groups except normal control group. But the recovery differs in different groups, and neurological function of rats in the MSCs group recovers better than that in other groups.

Objective To compare the performance of HP-083/4 and rational used instrument on detecting six items.Methods The rational instruments were used as contrast instrument,HP-083/4 was the verified instrument.A total of 100 blood specimens and 100 urine specimens were collected,and the levels of antistreptolysin O(ASO),hypersensitive C reactive protein (hsCRP),D-di-mer(D-D),glycosylated hemoglobin(HbA1c),rheumatoid factor(RF)and urine microalbumin(mAlb)were detected.The regression equation and correlation coefficient(r)of the two methods were calculated,and the Kappa values(κ)were analyzed to evaluate the performance of HP-083/4.Results There was a good linear correlation (r >0.950)for the two methods in detecting the serum ASO,hsCRP,D-D,HbA1c,RF and mAlb,r were 0.991,0.995,0.970,0.957,0.980 and 0.967 respectively.Besides,they had good concordance(κ>0.6),theκ values were 0.830,0.957,0.601,0.720,0.920 and 0.694 respectively.Conclusion HP-083/4 is effec-tive in detecting ASO,hsCRP,D-D,HbA1c,RF and mAlb,which should be suitable for clinical application.

AIM: To investigate the expression of voltage-gated chloride channels (ClC)-3 protein and mRNA in human glioma specimen and its biological function. METHODS: The expression of C1C-3 was observed by immunohistochemical staining in 24 cases of human glioma, 4 cases of brain metastic cancer specimens and 5 cases of normal brain tissue as control; The C1C-3 mRNA expression were detected in the specimens with positive expression of ClC-3 protein by RT-PCR. RESULTS: ClC-3 protein was found negative in 4 cases of normal brain tissues and positive in 19 cases of human glioma and 4 cases of brain metastic cancer specimens. ClC-3 protein was mainly expressed in the membrane or cytoplasm of neoplastic cells and microvascular endothelial cells. The expression of ClC-3 mRNA was detected in 16 cases of human glioma and 4 cases of brain metastasis cancer specimens among the tissues with the positive expression of ClC-3 protein. The level of protein and RNA of ClC-3 in high malignant oligodendrogliomas was higher than that in low malignant ones. CONCLUSION: ClC-3 is generally expressed in human glioma and brain metastic cancer and is probably correlated with the classification of its pathological malignance.

OBJECTIVE To investigate the effect of mono-2-ethylhexyl phthalate(MEHP) on proliferation of primary neural stem cells(NSCs)of rats and NE-4C cells of mice and on the migration of NE-4C cells and the mechanism. METHODS NE-4C or NSCs were treated with MEHP 1,10,100 and 1000 μmol · L-1 for 72 h,respectively. The cytotoxicity was estimated with the cell counting kit-8 (CCK-8). Cell proliferation was analyzed by EdU assay. The mRNA expression levels of the glucocorticoid receptor(GR),signal transducer and activator of transcription 3(Stat3)and sex determining region Y (SRY)-box 2(Sox2) were detected by qRT-PCR. The protein expression levels of total GR,GRβ, Sox2,Stat3 and p-Stat3 were measured by Western blotting. RESULTS Cell viability of NE-4C cells and NSCs at MEHP 1000μmol·L-1 was significantly decreased,which was 70.3%and 40.0%of the control group, respectively. EdU assay showed that MEHP 100 μmol · L-1 decreased NE-4C cells and NSCs by 74.8%and 12.0%(P<0.05)compared with control. The effect of MEHP on the cell migration of NE-4C was evidenced by the fact that the migration was obviously reduced to (63.4±2.0)%(P<0.05)after treatment with MEHP 100μmol · L-1 for 72 h. The mRNA expression levels associated with proliferation and migration in NE-4C of GR,Stat3 and Sox2 in MEHP 100 μmol · L-1 group were down-regulated to 49.8%,26.0% and 14.0%of control(P<0.05). At MEHP 100μmol · L-1,mRNA of GR, Stat3 and Sox2 in NSCs declined to 10.0%,14.0% and 15.3% of normal control. Western blotting results revealed that protein expressions of GR,GRβ,Sox2 and p-Stat3 were remarkably inhibited by MEHP 100 μmol · L-1 in that the relative expression of NE-4C was 0.92 ± 0.17,0.87 ± 0.35,0.81 ± 0.22 and 0.62 ± 0.24(P<0.05). The corresponding protein expression in NSCs was 0.82 ± 0.20,0.56 ± 0.12,0.84 ± 0.36 and 0.53 ± 0.20(P<0.05)when the cells were treated with MEHP 100μmol · L-1 for 72 h. CONCLUSION MEHP can inhibit the proliferation and migration of NE-4C cells and NSCs possibly by decreasing Stat3 and Sox2 that are mediated by GRβ.

Objective:To investigate the prognostic significance of D-dimer level in patients with diffuse large B-cell lymphoma (DLBCL).Methods:The clinical data of 70 newly diagnosed DLBCL patients who were admitted to Tianjin People's Hospital from January 2015 to June 2019 were retrospectively analyzed. The optimal cut-off value of D-dimer for survival was determined according to the receiver operating characteristic (ROC) curve, and the patients were grouped. The differences of coagulation related indexes and clinicopathological features between patients with different D-dimer levels were compared. Kaplan-Meier method was used for univariate analysis of overall survival (OS), and Cox regression model was used for multivariate analysis of OS.Results:According to ROC curve, the best cut-off value of D-dimer for survival was 0.75 mg/L. The proportion of patients with different clinical staging, international prognostic index score, lactate dehydrogenase level had statistically significant differences between the D-dimer ≥0.75 mg/L group (36 cases) and <0.75 mg/L group (34 cases) (all P < 0.05). The prothrombin time of D-dimer ≥ 0.75 mg/L group and < 0.75 mg/L group were (13.5±0.9) s and (13.0±0.8) s, respectively, and the activated partial thromboplastin time were (37±5) s and (34±6) s, respectively,and the differences were statistically significant (all P < 0.05). Univariate analysis showed that the 5-year OS rates of DLBCL patients with Ann Arbor stage Ⅲ-Ⅳ, international prognostic index score > 2, lactate dehydrogenase level > 240 U/L, B symptoms, D-dimer level ≥0.75 mg/L were decreased (all P < 0.05). Multivariate Cox regression analysis showed that D-dimer ≥0.75 mg/L was an independent risk factor for OS of DLBCL patients ( HR=0.368, 95% CI 0.144-0.944, P= 0.038). Conclusion:The level of D-dimer can be used as a clinical indicator to judge the prognosis of DLBCL patients, and the prognosis of patients with high D-dimer level is poor.