ABSTRACT
BACKGROUND:Irreducible femoral neck fracture was difficult to obtain anatomic reduction.As a new type of internal fixation,the femoral neck system is still blank for the treatment of non-anatomical reduced femoral neck fractures. OBJECTIVE:To explore the biomechanical stability of femoral neck system internal fixation under nonanatomical reduction in the treatment of femoral neck fractures based on finite element analysis. METHODS:CT data of the hip joint of a healthy female adult were obtained.Anatomical reduction of femoral neck fracture models with Pauwels angles of 30°,50°,and 70° were established using Mimics 21.0,Geomagic Wrap 2021,and SolidWorks 2020.The fracture proximal ends of the three anatomical reduction models were shifted upward by 2 mm along the fracture line,and three positive buttress models with different Pauwels angles were obtained.In the same way,three negative buttress models were acquired by shifting downward by 2 mm.SolidWorks 2020 was used to make the femoral neck system internal fixation,and the nine femoral neck fracture models were assembled with the femoral neck system.Then Ansys 19.0 was used for finite element analysis.The displacement distribution and maximum displacement,stress distribution and maximum stress of the femur and femoral neck system were recorded under 2100 N stress. RESULTS AND CONCLUSION:(1)When Pauwels angles were 30°,50°,and 70°,the maximum stresses of the femoral neck system appeared to be concentrated at the junction of the sliding hip screw and anti-rotation screw.The maximum femur stresses appeared to be concentrated in the medial cortex of the femur.The maximum displacement was concentrated at the upper of the femoral head and femoral neck system.(2)When Pauwels angles were 30° and 50°,the maximum displacement and maximum stress of the femoral neck system and femur were:negative buttress>anatomical reduction>positive buttress.(3)When Pauwels angle was 70°,the maximum displacement and maximum stress of the femoral neck system were:negative buttress>anatomical reduction>positive buttress;the maximum displacement and maximum stress of the femur were:negative buttress>positive buttress>anatomical reduction.(4)With the increase of Pauwels angle,the biomechanical advantage of the positive buttress was weakening.However,it was better than a negative buttress.When Pauwels angle was 30°,positive buttress was more stable than anatomical reduction.When Pauwels angle was 50°,the biomechanical difference between positive buttress and anatomical reduction became smaller.When Pauwels angle was 70°,the stability of anatomical reduction was slightly better than positive buttress.(5)If it was difficult to achieve anatomical reduction of femoral neck fracture during operation,but the positive buttress had been displaced within 2 mm,the femoral neck system could be used to offer stable mechanical fixation.It is necessary to avoid negative buttress reduction.
ABSTRACT
BACKGROUND: Osteoporosis is a balance disorder between bone formation of osteoblasts and bone resorption of osteoclasts during bone remodeling. Strict control of bone remodeling at the cellular level is important to maintain bone homeostasis and avoid osteoporosis. Previous studies have shown that 1.25×10-2 g/L mogroside V can promote osteoblast proliferation and differentiation, and its mechanism may be related to LncRNA TUG1. OBJECTIVE: To investigate the role of LncRNA TUG1 in the promotion of osteoblast proliferation and differentiation by mogroside V. METHODS: Osteoblasts from neonatal Sprague-Dawley rats were extracted by two-step enzymatic digestion. The cells were divided into two groups and treated with 0 and 1.25×10-2 g/L Mogroside V. The LncRNA was detected after 2 days of culture. LncRNA TUG1 silencing virus was designed and synthetized. The newly extracted osteoblasts were divided into normal cell control group, mogroside V intervention group, mogroside V+negative virus group, TUG1 silent group, and mogroside V+TUG1 silent group. The proliferation of osteoblasts was observed by FDA fluorescence staining at 2, 4, and 6 days after processing according to the above grouping conditions. After 6 days of treatment on osteoblasts, the effect of TUG1 on osteoblast proliferation and differentiation was studied by alkaline phosphatase staining, alizarin red staining and qRT-PCR. RESULTS AND CONCLUSION: LncRNA detection showed that 1.25×10-2 g/L Mogroside V significantly promoted the expression of LncRNA TUG1 in osteoblasts. FDA fluorescent staining showed that silencing of TUG1 inhibited the positive effect of mogroside V on osteoblast proliferation. After 6 days of treatment, alkaline phosphatase staining and alizarin red staining showed that silencing of TUG1 inhibited the positive effect of mogroside V on mineralization of osteoblasts. The results of qRT-PCR showed that Runx2, BSP, OCN and COL1A1 genes were highly expressed in the mogroside V intervention group, but their expression was inhibited in the mogroside V+TUG1 silent group. Overall findings indicate that mogroside V stimulates the proliferation and differentiation of osteoblasts by promoting the expression of LncRNA TUG1.
ABSTRACT
<p><b>OBJECTIVE</b>To observe effect of Xue Hanjing oral fluid on mice immunological function.</p><p><b>METHOD</b>The weight of thymus gland and spleen and the function of abdominal cavity macrophage were measured. Production of the hemolysin antibody, the immunoglobulin of blood serum and complement and the proliferation of T lymphocytes were observed respectively by means of microblood, immune-turbidimetry and MTT staining.</p><p><b>RESULT</b>Xue Hanjing oral fluid could enhance index of the thymus gland and spleen and the phago-percent of abdominal cavity macrophage, increase the immunoglobulin of blood serum(IgG and IgM), and accelerate production of the hemolysin antibody and the proliferation of T lymphocytes.</p><p><b>CONCLUSIONS</b>Xue Hanjing oral can reinforce immunological function in mice.</p>