1.Biomechanical study on femoral neck fracture fixation based on cortical screw support theory
Lijiang WANG ; Haiqiang WEI ; Lianjiang GUO ; Ning LI ; Aqin PENG
Chinese Journal of Trauma 2009;25(7):614-617
Objective To evaluate the biomechanical effect of cortical screw support technique in fixation of the femoral neck fractures. Methods The models of subcapital femoral neck fracture were made in eight matched pairs of embamled cadaver femurs and decided into experiment group and control group (four pairs per group). The side of experiment group was fixed using three cannulated compression screws with cortical screw support and that of control group with conventional screw placement. The speci-mens in two groups were tested in aspects of torsion and axial loading. Results In axial load test at load of 600 N and 800 N, the displacements in cortical screw support group were (0.677±0.135) mm and (0.907±0.132) mm respectively, while those of femoral head in conventional screw placement group were (0.899±0.160) mm and (1.202±0.152) nun respectively (P <0.05). There was signifi-cant difference between the two groups (P < 0.05). The maximal vertical loading for failure of the fixa-tion was (2 782±228) N in cortical screw support group and (1 950±281) N in conventional screw placement group (P < 0.01). In torsibility test at 4° and 6° torsibility, the torque-moments of cortical screw support group were (10.406±1.515) Nm and (15.328 ±1.471) Nm respectively and those of conventional screw placement group (6.628±1.163) Nm and (9.072±1.570) Nm respectively, with statistical difference between two groups (P <0.01). The maximal torque-moment for failure of the fixa-tion was (25.437±5.213) Nm in cortical screw support group and (13.235±3.012) Nm in conven-tional screw placement group (P < 0.01). Conclusion Fixation of femoral neck fractures by using cortical screw support can significantly enhance anti-torsion and anti-compression of internal fixation.
2.Research progress in the relationship between betatrophin and diabetes mellitus
Lijiang LI ; Xiangying LI ; Xiaofeng MIAO ; Xuejing YU ; Sanmin GUO ; Jian SUN
Basic & Clinical Medicine 2017;37(1):114-117
Betatrophin is a newly found factor that affects the metabolisms of sugar and fat , which is mainly ex-pressed in the liver and adipose tissue .This factor not only has an influence on the glucolipid metabolism , but also has regulating effect on replicating pancreatic βcell.Glucose and lipid metabolic disorder and the decrease in the number of pancreatic βcell are main risk factors of diabetes , diabetic great vascular complications and other com-plications.Therefore, betatrophin level has close relationship with diabetes .
3.The role of histone demethylase KDM2A on airway inflammation and airway remodeling in a rat asthma model
Zhixia Wang ; Xiang Luo ; Lijiang Wang ; Yan Liu ; Chun Guo ; Yang Yang ; Zhiqiang Zhang
Acta Universitatis Medicinalis Anhui 2022;57(4):610-615
Objective:
To investigate the role of protein demethylase of lysine-specific demethylase 2 A(KDM2 A) in airway inflammation and remodeling in rats with bronchial asthma.
Methods:
Intraperitoneal injection of chicken ovalbumin(OVA) sensitized aerosol to stimulate the asthma rat model. Eighteen 6-8 weeks old SPF SD female rats were randomly divided into 3 groups, namely the control group, the asthma group for 4 weeks, and the asthma group for 8 weeks. After the success of the asthma model, the infiltration of inflammatory cells in the trachea and perivascular of the lung tissue was observed by HE staining; Goblet cell proliferation and mucus secretion were observed by PAS staining; Masson staining was used to observe the fibrosis of airway wall; The proliferation of airway smooth muscle was observed by fluorescence immunohistochemistry; The protein expression level of KDM2 A was detected by Western blot.
Results:
The inflammatory scores and inflammatory cell counts of rats in the asthma 4-week group and the asthma 8-week group were higher than those in the control group. There was a statistically significant difference in the above indicators between the asthma two groups(P<0.01). Compared with the control group, the proliferation of goblet cells and mucus secretion in the airway epithelium, the deposition of collagen fibers in the lung tissue and the proliferation of bronchial smooth muscle cells increased in the asthma groups(P<0.01). With the prolonged OVA sensitization time, airway inflammation and airway remodeling changes were more severe in the asthma 8-week group than those in the asthma 4-week group. The results of Western blot showed that the expression of KDM2 A in the lung tissues of the asthmatic 4-week group and the asthmatic 8-week group was higher than that of the control group, and the expression of KDM2 A in the asthma 8-week group was also higher than that of the asthma 4-week group. The differences were statistically significant(P<0.01). The expression of KDM2 A protein in lung tissue of rats in each group was positively correlated with airway inflammation score, total number of inflammatory cells, goblet cell mucus secretion score, lung tissue fibrosis ratio, and airway smooth muscle hyperplasia area(allP<0.01).
Conclusion
KDM2 A may play an important role in the pathogenesis of airway inflammation and airway remodeling in bronchial asthma.
4.Mechanism of action and clinical research progress of iguratimod in connective tissue diseases
Xiaorong YANG ; Shuhong ZHOU ; Lijiang GUO ; Ying CHEN ; Yingying JI ; Lijie XU
China Pharmacy 2024;35(5):629-634
As a new type of immunosuppressant,iguratimod can mediate the anti-inflammatory signaling pathway by inhibiting the proliferation of inflammatory cells and reducing the release of inflammatory cytokines, and play the role of anti-inflammatory. It can affect the proliferation of immune cells and the expression of immune factors,reduce the production and deposition of immune complexes in the body,and play the role of immune regulation. It can regulate bone metabolism by mediating signaling pathways such as Wnt/β-catenin,Toll-like receptor 4/nuclear factor-κB and osteoprotegerin/nuclear factor-κB receptor activating factor ligand, and play a role in bone protection. It can inhibit pulmonary fibrosis by inhibiting the expression of transforming growth factor β1/ Smad2/3 signaling pathway,tumor necrosis factor-α,interleukin-1,interleukin-6,matrix metalloproteinase-9 and other inflammatory cytokines in lung tissue,and inhibiting the expression of collagen and fibronectin. Its efficacy and safety have been confirmed in the clinical application of rheumatoid arthritis and primary Sjogren syndrome and included in the diagnosis and treatment of the disease. It has also shown good efficacy in the clinical application of other connective tissue diseases such as systemic lupus erythematosus and ankylosing spondylitis,and no obvious safety risks have been found.