Objective To assess the level and trend of community acquired respiratory distress syndrome (CARDS) toxin after the infection of Mycoplasma pneumonia(MP),and evaluate the clinical characteristics,the level of immunoglobulin E (IgE) and interleukin-4 (IL-4) so as to find the association among these factors.Methods According to whether the child had wheezing symptoms,all the 63 children were divided into wheezing group (26 ca-ses) and non-wheezing group (3 cases).The levels of CARDS toxin were respectively detected in the acute stage of MP infection,3 and 6 months later after MP infection in different groups,moreover,IgE and IL-4 levels were monitored at the same time.Results (1) The mean level of IgE were (384.96 ± 316.62) × 103 IU/L and (87.32 ± 66.32) × 103 IU/L in wheezing group and non-wheezing group,respectively,and there was statistically significant difference (P ＜ 0.05).(2) The load of CARDS toxin in wheezing group and non-wheezing group were (1.87 ± 0.62) Delta Rn and (1.15 ± 0.48) Delta Rn in the stage of acute infection,respectively,and there was statistically significant difference (P ＜ 0.05).Nevertheless,differences between 2 groups after 3 months and 6 months were not significant.(3) In the acute stage,the level of CARDS toxin in the severe cases were higher than the mild cases [(2.37 ± 0.37) Delta Rn vs (1.21 ± 0.45) Delta Rn],and there was statistically significant difference (P ＜ 0.05).(4) IL-4 showed significant difference in the acute stage and 3 months later after acute infection between 2 groups,however,there were no difference between 2 groups after 6 months later.(5)The load of CARDS toxin showed no significant difference between 2 groups at 3 months [(0.96 ± 0.35) vs.(0.99 ± 0.40) Delta Rn,P =0.757] and 6 months [(0.67 ± 0.20) vs.(0.69 ±0.32) Delta Rn,P =0.641] later after MP infection.(6)The children in wheezing group coughed for (24.89 ±7.04) days after acute infection and the last time for non-wheezing group was (16.46 ± 4.79) days,and there was statistically significant difference(P =0.000).Conclusions The load of CARDS toxin decreased after acute MP infection and it was still detectable six months after onset in the blood.The level of CARDS toxin was associated with the cough and wheezing symptom and the severity of disease.

Objective To analyze the differences of von Mises stress distribution in knee cartilage and meniscus in female with generalised joint hypermobility (GJH) and healthy female during drop jump landing. Methods The kinematic and ground reaction force (GRF) characteristics of knee joint in female with GJH and healthy female at the moment of peak vertical GRF (VGRF) during loading phase of drop jump landing were collected. The knee joint reaction force was calculated via inverse dynamics, and the combined force of knee joint along long axis of the femur was applied as the load. Based on three-dimensional (3D) finite element model of a female knee joint, numerical simulations were performed separately during drop jump landing of subjects in two groups, and von Mises stresses and stress distribution of knee cartilage and meniscus were calculated. Results At the moment of peak VGRF during drop jump landing, knee flexion and valgus angles in GJH group and control group showed a statistical significance (P<0. 05). Compared with control group, knee flexion angle decreased and valgus angle increased in GJH group. During drop jump landing, GJH group bore larger stress inside the knee joint, and stress distribution in weight-bearing areas of the medial and lateral tibiofemoral compartments was uneven, while the lateral femoral cartilage lateral condyle, the anterior and middle lateral of lateral tibial cartilage, the anterior angle and body lateral margin of lateral meniscus were stress concentration sites. Conclusions For females with GJH, the stability of knee joint decreases and force lines change in jumping events, due to the increased range of motion of knee joint and relaxation of joint capsule, which increases the risk of cartilage and meniscal injury in lateral knee joint. During jumping sports, females with GJH should especially prevent knee joint injury caused by altered force lines in frontal plane of knee joint.