Objective To identify the effect of insulin-like growth factor-1(IGF-1) gene transfer on motoneurons apoptosis in anterior horn after acute spinal cord injury in adult rats.Methods Thirty-six male Wistar rats were randomly divided into 3 groups: IGF-1 group,model group and control group.The SCI models were made by cutting half spinal cord of rats on the T_8 segment by ophthalmogy scissors.Lipofectamine and recombinant plasmid pcDNA-hIGF-1 complexes were injected into the injury spinal cord by microinjector in IGF-1 group while pcDNA3.1,LipfectAmine and saline were administered in model group.The expression of IGF1 was detected by immunohistochemistry method,the apoptosis of the motoneurons in anterior horn was detected by TUNEL,and moting function of hindlimbs was evaluated by BBB locomotor scale.Results Compared with model group and control group,the expression of IGF-1 was increased significantly(P

0.05).)Conclusion The extra-pedicular technique is feasible in biomechanics.

Objective To identify the effect of morphology of adult upper and middle thoracic pedicle on security of screw implantation.Methods Five fresh adult cadaveric thoracic spine from T1 to T8 were harvested.Pedicle transverse diameters were measured and compared with the smallest diameter(4.5 mm) of screw used in clinic.The screws were inserted and implant effect was observed.Results The mean transverse diameter of adult thoracic(T1-T8) were T1:4.74(3.85-5.25)mm,T2:4.51(3.45-5.25)mm,T3:4.15(3.60-4.65)mm,T4:3.75(3.10-4.50)mm,T5:4.25(3.70-4.65)mm,T6: 4.53(4.40-4.70)mm,T7:5.38(5.25-5.60)mm,T8:5.55(5.50-5.80)mm.Of all specimens,there were 9 specmen(22.5%) whose tranverse diameters were smaller than 4.5 mm.After implantation,two screws broke through pedicle lateral wall.Conclusion Adult pedicle transverse diameters in T3-T4 are smallest,transpedicular screw placement is difficult in some of these vertebrae,but in most of thoracic vertebrae,pedicle tranverse diameter could permit screw implanting in security.

Objective To establish a model of respiratory mechanics with consideration of gas exchange and directly correlate with the gas content in blood during mechanical ventilation with the mechanics of respiratory system. Methods By coupling the physiological parameters of respiratory system and blood circulation system, including the molecular numbers of oxygen and carbon dioxide in alveoli and clinically monitored physiological parameters such as gas content, hemoglobin content, heart rate and cardiac output, a mechanical model was constructed to predict those dynamic parameters of gas content, pressure and flow rate in airway and alveoli in continuous breathing cycles. Results The gas content in different locations of a respiratory system was estimated by the model and the sensitivity of gas content in expiration to the undetermined parameters was evaluated. Conclusions The model of respiratory mechanics developed in the study is a preliminary attempt to predict the regulation roles of physiological parameters clinically monitored during mechanical ventilation, which will provide a theoretical support for the design and development of novel respirators in the follow-up experiment.

Objective To investigate the disease progression and influencing factors of human immunodeficiency virus (HIV)-infected persons in Sanya area from 2010-2020. Methods Data of HIV infected cases reported in XX region from January 2014 to January 2020 were collected through the National AIDS Comprehensive Prevention and Control Information System. The incidence of AIDS was calculated by the life expectancy method, and the single factors influencing the progression of HIV infection were analyzed from the aspects of sex, age, BMI, nationality, marital status, educational level, highly active anti-retroviral therapy (HAART), anemia, route of transmission, CD4⁺ cell count, and co-infection of other viruses. Results A total of 761 HIV-infected cases were reported in Sanya areaFrom January 2010 to January 2020, of which 103 had progressed to AIDS (13.53%), the incidence of AIDS was 6.01/100 person-years, the average incubation period was 4.63 years; There were 31 death cases, and the all-cause mortality rate was 1.81/100 person years; Gender, age, HAART treatment status, anemia, CD4⁺ cell count, and other viral infections were single factors that affect the disease progression of HIV-infected persons (χ²=16.803, 13.362, 15.954, 20.119, 16.039, 15.711, P<0.05), meanwhile, age, HAART treatment status, anemia, CD4⁺ cell count, and other viral infections were independent risk factors that affect the disease progression of HIV-infected persons (P=0.014, 0.007, 0.017, 0.009, 0.001, 0.001). Conclusion The incubation period is an important stage of the disease progression of HIV-infected patients, moreover, age, HAART treatment status, anemia, CD4⁺ cell count, and other viral infections are all independent risk factors that affect the disease progression of HIV-infected patients.