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Objective:To study the effects of enoxaparin on osteogenic differentiation of bone marrow stem cells (BMSCs) and the exosomes derived from BMSCs.Methods:After the BMSCs from 4-week old male SD rats were cultured, their surface antigen and multilineage differentiation potentials were identified. Subsequently, the BMSCs were incubated with osteogenic differentiation medium containing 10 IU/mL enoxaparin for 14 days. After the exosomes derived from BMSCs (BMSC-Exos) were extracted by the kit method, their structure was observed by transmission electron microscopy and their surface antigen CD63 detected by Western blot. Alizarin red staining was used to analyze the osteogenic differentiation of BMSCs. Osteogenic proteins including OCN and BMP-2 in BMSCs and exosomes were detected.Results:The spindle-shaped BMSCs isolated and cultured showed a uniform spiral pattern. They expressed highly the surface markers CD29 and CD44 but lowly CD34 and CD45, indicating that the majority of the cells were BMSCs. BMSC-Exos, in an oval shape with a diameter of about 30 to 80 nm, expressed CD63. Alizarin red staining showed that the number of mineralized nodules in the enoxaparin treatment group was significantly lower than that in the control group. Western blot analysis indicated that enoxaparin inhibited the expression of osteocalcin (OCN) and BMP-2 in BMSCs. ELISA results showed that the protein levels of OCN(48.81 ng/mL ± 8.23 ng/mL) and BMP-2 (311.45 pg/mL ± 27.59 pg/mL) in the BMSCs treated with enoxaparin were significantly lower than those of OCN (80.43 ng/mL ± 10.74 ng/mL) and BMP-2 (399.23 pg/mL ± 32.25 pg/mL) in the control BMSCs ( P<0.05). The contents of OCN (1.45 ng/mL±0.15 ng/mL) and BMP-2 (18.47 pg/mL ± 0.54 pg/mL) in the exosomes from BMSCs treated with enoxaparin were significantly higher than those of OCN (1.00 ng/mL ± 0.12 ng/mL) and BMP-2 (9.07 ng/mL ± 0.36 pg/mL) in the exosomes from control BMSCs ( P<0.05). Conclusions:Enoxaparin may inhibit the osteogenic differentiation of BMSCs. The mechanism of this might be related to its direct inhibition against the expression of OCN and BMP-2 in BMSCs and its indirect reduction of OCN and BMP-2 in BMSCs through the exhaust of the above proteins in the form of exosomes.
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Objective To evaluate the clinical and radiologic outcomes of minimally invasive plate percutaneous osteosynthesis (MIPPO) for distal clavicle fractures of Neer type Ⅱ. Methods From May 2015 to May 2016, 13 patients with distal clavicle fracture of Neer type Ⅱwere treated with MIPPO using an anatomic locking plate. Anteroposterior plain X-ray images of the clavicle were taken at intervals until union was observed. Fracture healing time and complications were recorded, and shoulder joint functions evaluated using Constant and University of California at Los Angeles (UCLA) scores. Results The average operating time was 60.9 minutes (range, from 48 to 83 minutes), average intraoperative blood loss 24.7 mL (range, from 18 to 30 mL), and average union time for the patients was 13.3 weeks (range, from 11 to 15 weeks). No delayed union or nonunion occurred. There were no major complications, like infection, plate breakage, or neurovascular injury. Only 2 patients felt local incision numbness. All the patients were satisfactory with their shoulder func-tions. At the final follow-ups, the mean Constant score was 93.2 points (from 87 to 95 points) and the mean UCLA score 30.6 points (from 28 to 34 points). Conclusion In the treatment of distal clavicle fractures of Neer type Ⅱ, minimally invasive plate percutaneous osteosynthesis can not only achieve good clinical and radi-ologic outcomes but also be advantageous over conventional open reduction in aspects of smaller invasion and better cosmetic effect.
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BACKGROUND:It is stil disputed at present about the treatment selection for clavicle fractures, operative or conservative treatment. OBJECTIVE:To evaluate the effects of operative and non-operative (conservative) treatment for clavicle fractures with the method of meta-analysis. METHODS: We retrieved PUBMED, EMBASE, OVID, Cochrane library, Science Direct, Springer Link, China National Knowledge Infrastructure and Wanfang Database for articles on treatment of clavicle fractures published from January 2000 to December 2013. According to specific inclusion and exclusion criteria, relevant literatures about treatments of clavicle fractures were searched for data source extraction, which were used for meta-analysis using Review Manager 5.0 software. RESULTS AND CONCLUSION:Six randomized controled trials were included, including 570 patients. Meta-analysis results demonstrated that for clavicle fractures, implant fixation could decrease nonunion rate [RR=0.16, 95%CI(0.07, 0.38),P < 0.000 1], malunion rate [RR=0.15, 95%CI(0.07, 0.34),P < 0.000 01], delayed union rate [RR=0.20, 95%CI(0.06, 0.70),P=0.01] and the incidence of residual pain at 1 year after treatment [RR=0.24, 95%CI(0.12, 0.51),P=0.000 2], could elevate Constant Score [MD=3.68, 95%CI(1.61, 5.76),P=0.000 5]. However, it was not concluded that fixation could reduce the incidence of neurological complications [RR=0.63, 95%CI(0.06, 0.70),P=0.22]. It is suggested that implant fixation for clavicle fractures obtained good clinical effects. However, due to the disadvantages of the included literatures, we stil needed high-quality multicenter randomized controled trials to further verify conclusions, and should pay more attention on patients’ individual conditions when the therapeutic methods for clavicle fractures were selected in the clinic.
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BACKGROUND:The in vivo degradation process of chitosan/hydroxyapatite composite porous scaffolds is not very clear. Research on the effects of rat osteoblasts and degradation products is less. OBJECTIVE:To analyze the biocompatiblity of rat osteoblasts with degradation products of chitosan/hydroxyapatite composite porous scaffolds. METHODS:The second generation of cultured rat osteoblasts were respectively cultured in the extract of degradation products of chitosan/hydroxyapatite composite scaffolds (experimental group) and Dulbecco’s modified Eagle’s medium containing 10%fetal bovine serum (control group). At 2, 4, 6, 8, 10 days of culture, cel counting was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Alkaline phosphatase activity was measured by the recommended method of determination of the Federation, and total protein was determined by BCA method. RESULTS AND CONCLUSION:The proliferation speed, alkaline phosphatase activity, total cel ular protein synthesis and ratio of alkaline phosphatase to total protein in rat osteoblasts cultured in the experimental group were significantly higher than those in the control group (P<0.05). This experiment showed that the degradation products of chitosan/hydroxyapatite composite porous scaffolds cannot only promote rat osteoblast adhesion, growth and proliferation, but also enhance its ossification function, with good biocompatibility.
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BACKGROUND:The degradation of a col agen Ⅰ modified porous calcium sulfate scaffold in vivo is unclear, and its degradation product effects on human osteoblasts are rarely reported. OBJECTIVE:To observe the biocompatibility of human osteoblasts with degradation products of calcium sulfate/col agen membrane composite porous scaffold. METHODS:Passage 2 human osteoblasts were cultured in the extract of degradation products of calcium sulfate/col agen membrane composite porous scaffold and in Dulbecco’s modified Eagle’s medium containing 10%newborn calf serum. At days 1, 3, 5, 7, cellproliferative curves and total protein were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method and Coomassie bril iant blue micro-plate method, respectively. And alkaline phosphatase activity was also detected. RESULTS AND CONCLUSION:The proliferation rate of human osteoblasts in the extract of degradation products of calcium sulfate/col agen membrane composite porous scaffold was slightly higher than that in the Dulbecco’s modified Eagle’s medium containing 10%newborn calf serum, but there was no significant difference (P>0.05). Alkaline phosphatase activity, total protein synthesis and alkaline phosphatase/total protein were increased with time in the two groups, but there was no significant difference at different time (P>0.05). These findings indicate that the degradation products of calcium sulfate/col agen membrane composite porous scaffold cannot influence proliferation and growth of human osteoblasts as wel as their normal physiological functions, which have good biocompatibility.
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BACKGROUND:Nowadays, the internal fixation materials for the clinical treatment of unstable femoral intertrochanteric fractures are broadly divided into two categories:intramedul ary fixation system and extramedul ary fixation system. However, the effects of the treatments usual y lack of macro evaluation. OBJECTIVE:To compare the effect of intramedul ary fixation system and extramedul ary internal fixation system in the treatment of unstable femoral intertrochanteric fractures. METHODS:217 patients with unstable femoral intertrochanteric fracture (Evans typing: Ⅲ type to Ⅴ type and R type) were treated by using intramedul ary fixation system and extramedul ary internal fixation system:18 cases were treated with dynamic condylar screw, 67 cases were treated with dynamic hip screw, 43 cases were treated with reconstruction nail, 72 cases were treated with proximal femoral anti-rotation blade nail, and 17 cases were treated with new generation of antegrade interlocking intramedul ary nail. The operative time, length of incision, blood loss, time in bed, fracture healing time, complications and Harris hip score were analyzed and compared. RESULTS AND CONCLUSION:In the aspects of operative time, blood loss, time in bed, complications and Harris hip score, the intramedul ary fixation system was superior to extramedul ary internal fixation system. But there were significant differences in the aspects of length of incision and fracture healing time between two methods. The results showed that the treatment of unstable femoral intertrochanteric fractures by using intramedul ary fixation system was better than the extramedul ary internal fixation system, as the intramedul ary fixation system could effectively shorten the operative time and reduce blood loss. This stable and reliable fixation enables patients to take early postoperative functional exercise, and could significantly shorten the time in bed and reduce the incidence of complications and it is conducive to postoperative hip function recovery. Therefore, intramedul ary fixation system is an ideal method for the treatment of unstable femoral intertrochanteric fractures.
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BACKGROUND:As an oral anticoagulant drug, many experiments have proved that rivaroxaban can prevent the deep venous thromboembolism after the hip arthroplasty. The foreign literatures indicate that it can significantly reduce the incidence of deep venous thromboembolism after extending the treatment course to 35 days. But there is no significant conclusion at home, and the safety of drugs after extentding the course has not been confirmed. OBJECTIVE:To analyze the efficacy and safety of rivaroxaban versus low-molecular-weight heparin for the prevention of deep venous thrombosis after the hip arthroplasty. METHODS:106 patients with primary unilateral hip arthroplasty in the Second Clinical Medical College of Shanxi Medical University between March 2011 and September 2012 were selected. The patients were randomly divided into rivaroxaban group and low-molecular-weight heparin group. The patients in two groups were given drugs at 6 hours after replacement, the patients in the rivaroxaban group were given rivaroxaban 10 mg/d with the course of 5 weeks;the patients in the low-molecular-weight heparin group were given low-molecular-weight heparin 4 100 U/d with the course of 2 weeks. RESULTS AND CONCLUSION:The review and fol ow-up results showed there was no deep vein thrombosis or symptoms of deep vein thrombosis in patients of the rivaroxaban group after replacement, while seven cases (13%) of deep vein thrombosis were observed in the low-molecular-weight heparin group, and there was significant difference in the incidence rate of deep vein thrombosis between two groups (P0.05). The results indicate that ful course of rivaroxaban has clear effect and reliable security in the prevention of deep venous thrombosis after hip arthroplasty.
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Objective To investigate the effect of insulin-like growth factor-1(IGF-1 ) on the osteogenic phenotype of fibroblasts. Methods Fibroblasts (Fbs) were derived from an adult New Zealand white rabbit through isolation,purification and cultivation.The experiment was conducted in 3 groups.In the control group,Fbs were cultured in conventional medium without any intervention factors.In the osteogenic induction group,the osteogenic induction medium was composed of conventional medium plus dexamethasone at concentration of 1 × 10-8 mol/L plus vitamin C at 50 mg/L plus sodium glycerophosphate-β at 10 mmol/L.In the experimental group,Fbs were cultured in osteogenic induction medium plus IGF-1 at the final concentration of50 ng/mL.Proliferation of Fbs in each group was detected by methyl thiazolyl tetrazolium (MTT)colorimetric assay.Alkaline phosphatase(ALP) activiiy was detected,osteocalcin 6 days after culture was determined,and the ability of osteogenic differentiation 2 weeks after culture was evaluated by calcium-cobalt staining. Results MTT showed that the cells grew significantly faster in the experimental group than in the other 2 groups( P ＜ 0.05),but there was no significant difference between the control group and the osteogenic induction group in this respect (P ＞ 0.05).The ALP expression in the experimental group was insignificantly higher than in the osteogenic induction group( P ＜ 0.05),but significantly higher than in the control group ( P ＜ 0.05).In osteocalcin secretory activity,the experimental group was significantly superior to the other 2 groups and the osteogenic induction group was significantly superior to the control group ( P ＜0.05).The experimental group had significantly more calcified nodules than the other 2 groups and there were few calcified nodules in the control group 2 weeks after culture. Conclusion IGF-1 can advance proliferation and osteogenic phenotype expression of the Fb stimulated.
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ObjectiveTo evaluate the effects of double plates in the treatment of humeral intercondylar fractures.MethodsFrom January 2004 to March 2011,31 patients with humeral intercondylarfractures were reviewed.According to AO/Müller classification,there were three patients with type C1 fractures,16 with type C2 and 12 with type C3.Trans-olecranon osteotomy or trans-triceps-side approach and internal fixation by standard method of AO double plates were performed in all patients.ResultsAll 31patients were followed up for 12 -18 months,which showed fracture healing 6-12 months after surgery.According to the Cassebaum scoring system,the effects were evaluated as excellent in seven patients,good in 19,fair in four and poor in one,with excellence rate of 87％. ConclusionDouble plates is proved to be a good choice for humeral intercondylar fractures,since it can obtain satisfactory outcome with solid fixation,stable mechanical properties,few complications and facilitation for early rehabilitation.
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Objective To discuss the efficacy of a modified single posterior fixation of complicated acetabular fractures with a percutaneous cannulated screw and a reconstruction plate in comparison with traditional bilateral approaches (ilioinguinal and Kocher-Langerbeek). Methods From April 2004 to May 2007, 48 cases of complicated acetabular fracture were treated surgically. By Letoumel classification, 22 were transverse and posterior wall fractures, 16 fractures of both columns, 3 fractures of anterior column and posterior wall, 3 T shape fractures and 4 anterior column and posterior hemi-transverse fractures. Of them, 22 cases were treated through the bilateral approaches and 26 cases through the modified single posterior approach by which a percutuneous cannulated screw was applied, going askew through skin and ischial tuberosity, to fix the anterior column and a reconstruction plate to fix the posterior column. Results Forty patients were followed up for 6 to 37 months(average, 18 months) . There was no statistical difference between the 2 groups as fax as the following factors were concerned: anatomic reduction rate and functional good-to-excellent rate. But there were significant differences in operation time and volume of hemorrhage during operation. Conclusion In treatment of complicated acetabular fractures, the modified singl eposterior approach simplifies traditional bilateral approaches so that surgery procedures, perioperative bleeding and postoperative complications can be reduced without sacrificing the treatment efficacy.