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【Objective】 To investigate the effects of biomimetic bone trabecular with the same porosity and pore size and regular porous structure on the adhesion, proliferation, and differentiation of osteoblasts, so as to provide theoretical basis for the improvement of osseointegration performance of titanium alloy implants. 【Methods】 The biomimetic bone trabecular and regular porous structures with the same porosity and pore size were generated by computer-aided software, and then processed into disc-shaped Ti6Al4V scaffolds with a diameter of 10 mm and a height of 3 mm by selective laser melting technology. MC3T3-E1 cells, the precursor cells of mouse osteoblasts in the logarithmic growth phase, were seeded on two kinds of scaffolds and divided into biomimetic bone trabecular group and regular porous structure group. After 3 hours of culture, acridine orange staining and phalloidin /DAPI staining were used to evaluate the number of cell adhesion. After 3 days of culture, the scaffolds were examined by scanning electron microscopy to evaluate the adhesion state of cells. After 1, 3, and 5 days of culture, the scaffolds were taken for CCK8 detection to observe the proliferation of cells. After 7 and 14 days of differentiation, alkaline phosphatase (ALP) activity was detected. After 14 days of differentiation, the expressions of osteogenesis-related genes (ALP, OCN, RUNX2) were detected by RT-PCR. After 30 days of differentiation, the scaffolds were stained with alizarin red and 100 g/L cetylpyridinium chloride was used to dissolve mineralized nodules. Calcium salt deposition was qualitatively and quantitatively detected to evaluate cell differentiation. 【Results】 The results of acridine orange and phalloidin /DAPI staining showed that the biomimetic trabecular Ti6Al4V scaffold adhered to more MC3T3-E1 cells than the regular porous structure, and the cytoskeleton of the former scaffold was more densely distributed. The results of scanning electron microscopy showed that the pseudopodia of MC3T3-E1 cells on the biomimetic bone trabecular Ti6Al4V scaffold were longer and the extension state was better than that of the regular porous structure. CCK8 test showed that the proliferation of MC3T3-E1 cells on the biomimetic trabecular bone titanium alloy scaffold was significantly higher than that on the regular porous structure on the 3rd and 5th day, and the difference gradually increased with the increase of time, with statistical significance (P<0.05). The results of cell differentiation test showed that ALP activity on the bionic trabecular scaffold was higher than that on the regular porous structure (P<0.05). The expressions of osteogenic genes (ALP, OCN, RUNX2) in MC3T3-E1 cells on the biomimetic bone trabecular titanium alloy scaffold were significantly higher than those on the regular porous structure (P<0.05). After 30 days of induction, the amount of calcium salt deposited in the bionic trabecular titanium alloy scaffold was significantly larger than that in the regular porous structure (P<0.05). 【Conclusion】 The biomimetic bone trabecular with a porosity of 65% and an equivalent pore size of 600 μm is more conducive to the adhesion, proliferation and differentiation of mouse osteoblast precursor cells MC3T3-E1 on the titanium alloy scaffold than the regular porous structure with the same porosity and pore size. It is theoretically more conducive to improving the osseointegration performance of titanium alloy implants.
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Background@#To evaluate the feasibility of treating odontoid fractures in the Chinese population with two cortical screws based on computed tomography (CT) scans and describe a new measurement strategy to guide screw insertion in treating these fractures. @*Methods@#A retrospective review of cervical computed tomographic scans of 128 patients (aged 18–76 years; men, 55 [43.0%]) was performed. The minimum external transverse diameter (METD), minimum external anteroposterior diameter (MEAD), maximum screw length (MSL), and screw projection back angle (SPBA) of the odontoid process were measured on coronal and sagittal CT images. @*Results@#The mean values of METD and MEAD were 10.0 ± 1.1 mm and 12.0 ± 1.0 mm, respectively, in men and 9.2 ± 1.0 mm and 11.0 ± 1.0 mm, respectively, in women. Both measurements were significantly higher in men (p 9.0 mm that could accommodate two 3.5-mm cortical screws. The mean MSL value and SPBA range were 34.4 ± 2.9 mm and 13.5°–24.2°, respectively, with no statistically significant difference between men and women. @*Conclusions@#The insertion of two 3.5-mm cortical screws was possible for anterior fixation of odontoid fractures in 87 patients (68%) in our study, and there was a statistically significant difference between men and women.
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Objective:To investigate the risk factors of refracture of the injured vertebrae after percutaneous vertebral augmentation for acute symptomatic thoracolumbar osteoporotic compression fractures (ASTOCFs).Methods:A case-control study was conducted to analyze the clinical data of 2 237 ASTOCFs patients admitted to three hospitals from January 2010 to January 2019. There were 569 males and 1 668 females, with age range of 50-85 years [(66.7±4.8)years]. The patients underwent percutaneous vertebroplasty (PVP) or percutaneous kyphoplasty (PKP). According to the radiographic outcomes, the patients were divided into refracture group ( n=315) and non-refracture group ( n=1 922). Data were recorded for the two groups, including basic demographics (gender, age, height and weight), personal habits (smoking and alcohol consumption), basic diseases (diabetes, hypertension, coronary heart disease and chronic obstructive pulmonary disease), preoperative bone mineral density, fracture segment, number of injured vertebrae, surgical method (PVP or PKP), surgical approach, bone cement viscosity, distance from cement to the upper and lower endplate, cement volume in injured vertebrae, cement leakage, postoperative exercise, and postoperative anti-osteoporosis treatment. The above data were analyzed to identify their correlation with postoperative refracture of the injured vertebrae by univariate analysis. The independent risk factors for postoperative refracture of the injured vertebrae were determined by multivariate Logistic regression analysis. Results:Univariate analysis showed that refracture of injured vertebrae was correlated with gender, age, diabetes, fracture segment, surgical method, distance from cement to the upper and lower endplate, postoperative exercise, and postoperative anti-osteoporosis treatment ( P<0.05 or 0.01), but there was no correlation with height, weight, smoking, alcohol consumption, hypertension, coronary heart disease, chronic obstructive pulmonary disease, preoperative bone mineral density, number of fractured vertebrae, surgical approach, bone cement viscosity, cement volume in injured vertebrae or cement leakage (all P>0.05). Multivariate Logistic regression analysis showed that female ( OR=1.92, 95% CI 1.34-2.64, P<0.01), age ≥80 years ( OR=1.21, 95%CI 1.17-1.25, P<0.01), diabetes ( OR=1.92, 95% CI 0.44-2.55, P<0.01), thoracolumbar fracture ( OR=1.46, 95% CI 1.82-7.51, P<0.05), PKP ( OR=4.56, 95% CI 0.86-1.44, P<0.05), no postoperative exercise ( OR=2.14,95% CI 0.27-0.38, P<0.01), and no postoperative anti-osteoporosis treatment ( OR=2.36,95% CI 0.13-0.47, P<0.05) were positively correlated with refracture of injured vertebrae. Conclusion:Female, age ≥80 years, diabetes, thoracolumbar fracture, PKP, no postoperative exercise, and no postoperative anti-osteoporosis treatment are independent risk factors for refracture of injured vertebrae after percutaneous vertebral augmentation for ASTOCFs.
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Objective To investigate the clinical pathologic features of a distinct variant of focal cortical dysplasia (FCD) characterized by neuronal loss of layer four.Methods Between 2005 and 2017,approximately 3 000 surgeries were performed for the treatment of intractable epilepsy at Xuanwu Hospital,Capital Medical University and Yuquan Hospital,Tsinghua University.Retrospective analysis of clinic-pathological data of patients with epilepsy surgery was made and histological manifestations of neuronal loss of cortical layer four were included in this study.Results In this cohort,25 patients (22 males and three females) were identified with early onset pharmaco-resistant epilepsy and regionally circumscribed neuronal loss of cortical layer four in surgical specimens from the occipital lobe.Histologically,except for neuronal loss in cortical layer four in all cases,glial scar lesions were found in some patients.Thus the histology of those cases can be subdivided into two groups:group A (13 cases):neuronal loss of cortical layer four without glial scar lesions;and group B (12 cases):neuronal loss of cortical layer four with glial scar lesions.Due to the prominent horizontal disorganization of cortical layering and lack of any other microscopically visible principle lesion,group A should be classified hitherto as FCD International League Against Epilepsy (ILAE) type Ⅰ b,however,group B with scar lesions and cortical dysplasia around the main leision,should be classified as FCD ILAE type Ⅲd.This retrospective analysis of clinical histories revealed a perinatal distress in 20 patients (80％),suggesting an acquired pathomechanism.Magnetic resonance imaging revealed abnormal signals in the occipital lobe in all patients,and signal changes suggestive of encephalomalacia were found in 18 patients.Surgical treatment achieved favorable seizure control (Engel class Ⅰ and Ⅱ) in 18 patients (75％ among 24 available follow up).Comparion of the two groups with age at epilepsy onset (group A:5.00±2.76,group B:5.01±3.78),the proportion of perinatal distress (group A:11/13,group B:9/12) and the follow-up results (favorable seizure control of the two groups was 9/13,9/11 respectively) showed that there was no statistically significant difference between the two groups.Conculsion Neuronal loss of cortical layer four in the occipital lobe should be classified as a distinct variant of FCD ILAE type Ⅲd.
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Objective To study the effect of total knee arthroplasty after limb position on postoperative hemorrhage,to provide basis for clinical diagnosis and treatment.Methods 270 cases of total knee arthroplasty were selected.The patients were divided into groupⅠ,group Ⅱand group Ⅲ according to the random number table method, 90 cases in each group.Patients of group Ⅰ with limb hip and knee were straight,group Ⅱ hip joint elevation of 45 degrees,70 degrees of knee flexion,group Ⅲ hip joint elevation of 45 degrees,the knee extension.All the patients were intervened for 12h after operation,were placed drainage bag 24 hours.The lead flow,preoperative,postoperative hemoglobin and 5 days after the knee joint activity were compared in the three groups.Results Induced flow after surgery in group Ⅰ was (433.4 ±25.3)mL,which was significantly higher than (402.6 ±19.6)mL and (403.5 ± 21.5)mL in group Ⅱand group Ⅲ,and the differences were statistically significant (t =5.253,5.301,all P 0.05).The hemoglobin levels of the three groups were (92.3 ±4.2)g/L,(114.9 ±6.4)g/L and (113.2 ±7.5)g/L,which were significantly decreased after operation,the differences were statistically significant compared with before operation (t =5.083, 6.034,7.893,all P 0.05).There was no significant difference of range of motion in the three groups after 5 days of operation (P >0.05).Conclusion Hip flexion can effectively reduce bleeding after total knee arthro-plasty,the flexion and extension of knee joint had no significant effect on postoperative hemorrhage.
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Objective To investigate the clinical effect of modified storage type of autologous blood transfu-sion combined with shed blooding retransformation technique after OrthoPAT for artificial total knee arthroplasty. Methods 70 patients with total knee replacement were randomly divided into observation group and control group, 35 cases in each group.The observation group was treated with the modified storage autotransfusion combined shed blooding retransformation technique after OrthoPAT,while the control group was given conventional allogeneic blood transfusion.The hemoglobin values and blood coagulation function of the two groups at immediately before anesthesia and surgery,10min before autologous blood transfusion and after reinfusion of 15min,after 6h and 24h of surgery were recorded,and the drainage blood total value,allogeneic blood transfusion measurement issues and transfusion rate after 24h were recorded.Results The hemodynamics of the two groups were stable at each time,there were no difference at urine volume (all P >0.05).The coagulation conditions were normal of the two groups at each time,there were no statistically significant differences between the two groups (all P >0.05).The average volume and homologous blood transfusion rate in the observation group were (126.3 ±6.5)mL,1 /35,which were significantly lower than those in the control group [(476.4 ±10.6)mL,2 /35],the differences were statistically significant (t =10.73,χ2 =6.31,all P <0.05).The incidence rate of postoperative complication of the observation group was 5.7%,which was signifi-cantly lower than 22.9% of the control group,the difference between the two groups was statistically significant (χ2 =4.93,P <0.05).Conclusion The improved storage type of autologous blood transfusion combined with shed bloo-ding retransformation technique after OrthoPAT has exact effect for artificial total knee arthroplasty,the incidence of adverse reactions is low,as well as the low blood transfusion rate.