Repair of femoral shaft fracture with bridging combined internal fixation and locking plate screw system：a biomechanical comparison / 中国组织工程研究

BACKGROUND:Different methods of internal fixation can be selected during the repair of femoral shaft fractures in the clinic, including bridging combined internal fixation and metal locking plate screw fixation. OBJECTIVE: To compare the biomechanical properties of bridging combined internal fixation and metal locking plate screw fixation for femoral shaft fracture. METHODS:Eighteen femoral samples were colected and randomly divided to three groups, with six in each group. In the normal control group, no treatment was given. In the other groups, models of femoral shaft fracture were established. In the bridging combination group, samples underwent bridging combined internal fixation. In the locking plate screw group, samples underwent metal locking plate screw fixation. Biomechanical test was conducted in samples of the three groups. In the femoral compression experiments, we recorded the maximum displacement under the maximal load 500 N. In the femoral flexion experiment, we recorded the maximum displacement under the maximal load of 100 N. In the femoral retroversion experiment, we recorded the maximum displacement under the maximal load of 100 N. RESULTS AND CONCLUSION: (1) Compression experiment at different loads: the maximum displacement was larger in the bridging combination group and locking plate screw group than in the normal control group. Under the maximum load of 500 N, the maximum displacement was significantly larger in the bridging combination group and locking plate screw group than in the normal control group (P < 0.05). Moreover, the maximum displacement was significantly less in the bridging combination group than in the locking plate screw group (P< 0.05). (2) Flexion experiment under different loads: the maximum displacement was larger in the bridging combination group and locking plate screw group than in the normal control group. Under the maximal load of 100 N, the maximum displacement was significantly larger in the bridging combination group and locking plate screw group than in the normal control group (P< 0.05). Moreover, the maximum displacement was significantly smaler in the bridging combination group than in the locking plate screw group (P < 0.05). (3) Retroflexion experiment under different loads: the maximum displacement was larger in the bridging combination group and locking plate screw group than in the normal control group. Under the maximal load of 100 N, the maximum displacement was significantly larger in the bridging combination group and locking plate screw group than in the normal control group (P < 0.05). Moreover, the maximum displacement was significantly smaler in the bridging combination group than in the locking plate screw group (P < 0.05). (4) These results suggested thatin vitro simulated femoral shaft fracture bridging combination fixation and metal locking plate screw system can obtain good fixation effect; the design meets the principle of biomechanics. Among them, bridging combined internal fixation can maintain a smaler displacement, suggesting good deformation resistance under compressive stress, anteflexion and retroflexion stress.

Preparation and immunogenicity of silk fibroin/chitosan microspheres for DNA vaccine delivery against infectious bursal disease virus / 生物工程学报

To evaluate the immunities of biodegradable microsphere as a release delivery system for DNA vaccine against Infectious Bursal Disease Virus, in our study, silk fibroin/chitosan microsphere adjuvant was prepared with a precipitation/coacervation method. Both glutaraldehyde and Na2SO4 solution were used in cross-linking. No immune chicken were intramuscularly inoculated at 14 day-old and boosted 2 weeks later. The results show that glutaraldehyde destroyed the DNA activity of the vaccine whereas Na2SO4 solution did not. Factors of the chitosan concentration 0.5% (pH 5.0), silk fibroin concentration 0.6%, plasmid DNA (500 microg/mL) dissolved in 2% Na2SO4 solution were optimized to produce microsphere, with a loading capacity of 89.14%. The average particle size of SF-CS/pCI-VP2/4/3 microsphere is 1.98 microm, and it can protect the loading DNA vaccine from DNase I digestion. Data from anti IBDV ELISA antibodies in the serum show that immunization activity of the microsphere groups were generally higher than plasmid vaccine group (P < 0.05), and the SF/CS compound microspheres group was better than that of sole CS microsphere group. The developed SF/CS microspheres are a very promising vaccine delivery system.

Prognostic factors of acute exacerbation of chronic obstructive pulmonary disease / 中国医师杂志

ObjectiveTo investigate prognostic factors in acute exacerbation of COPD (AECOPD).Methods352 AECOPD patients were investigated.26 possible variables were analyzed.Multivariate Logistic and Cox proportional-hazards regression analysis were used.ResultsAccording to multivariate Logistic regression,it showed seven factors were statistically significant for short term prognosis ( P ＜0.05 ),including PaO2 ( OR =0.082),CKMB ( OR =4.967 ),mechanical ventilation ( OR =6.903 ),albumin ( OR =0.221 ),FEV1％ ( OR =0.255 ),charlson index ( OR =8.406 ) and hospital day ( OR =0.075).According to multivariate Cox regression,it showed seven factors were statistically significant for long term survival ( P ＜ 0.05 ) including acute exacerbation frequency( HR =1.611 ),charlson index( HR =4.319),SaO2 ( HR =0.224 ),troponin Ⅰ ( HR =3.824 ),albumin ( HR =0.569 ),hospital day ( HR =0.456) and FEV1％ (HR =0.494).Acute exacerbation frequency was correlated with dyspnea scale( rs =0.508,P ＜ 0.01 ).ConclusionsPaO2,albumin,FEV1％,CKMB and charlson index were related with short term prognosis.SaO2,albumin,FEV1 ％,troponin Ⅰ,charlson index and acute exacerbation frequency were related with long term survival.Higher acute exacerbation frequency contributed to more severe breathing difficulties and worse quality of life.

Clinical Observation on the Treatment of Rheumatoid Arthritisin Early Stage with TongLuoShu Liquid / 国际中医中药杂志

Objective To investigate the clinical efficacy of TongluoShu Liquid in treating rheumatoid arthritis at early stage. Methods 100 cases were randomly recruited into a control group and a treatment group with 50 cases in each group. The treatment group was given TongluoShu liquid, 150ml / time, twice a day; and the control group was given Diclofenac Sodium Sustained Release Tablets (Deegan), one granule for each time, twice a day, and Methotrexate 7.5mg / time, once per week. Results In the treatment group, symptoms, signs and biochemical indicators were significantly improved, and the swelling of the soft tissue around the joints in stage Ⅰ and Ⅱ were also reduced. Besides, osteoporosis was controlled and the progress of destruction to the cartilage of stage Ⅲ was detained, though there was no statistical difference between the two groups after the treatment. Conclusion ShuTongluo liquid is a safe and effective medicine with less adverse reactions in treating rheumatoid arthritis.