Objective To explore the incidence and clinical characteristics of the anterior tibial translation(ATT) after anterior cruciate ligament injury.Methods One hundred and fifty-three patients with the anterior cruciate ligament injury underwent standard magnetic resonance imaging scans with full knee extension.Based on the relative location between the lateral tibial plateau and the lateral femoral condyle,all the patients were divided into an ATT positive group and an ATT negative group.Moreover,the posterior tibial slope angle(PTSA),the continuity of anterolateral ligament(ALL),and the integrity of posterior horn of the lateral meniscus of all the patients were detected so as to find the risking factors for ATT.Results Among the 153 patients,46 patients were finally confirmed to have ATT.Moreover,the average PTSA of the ATT positive group was significantly larger than that of the ATT negative group.However,there were no significant differences between the two groups in the continuity of ALL and the integrity of posterior horn of lateral meniscus.Conclusion In this study,the incidence of ATT was 30.1％,which may be correlated to the increased PTSA.

Objective To get a controllable acetabulum component inclination angle during the total hip arthroplasty(THA) with the lateral position,a new method using a self-made instrument was introduced.Methods Totally 80 consecutive patients undergoing THA at the lateral position were enrolled.Forty acetabular components were assembled using a new method with a self-made instrument referring to the 42 degrees' angle drawn on the wall(group A),while another 40 acetabular cups were implanted free-handedly(group B).The postoperative inclination angle was evaluated on the anterior-posterior pelvic radiographs.Results The average inclination angle was 43.3° ± 3.7°(34.7°～49.1°) in group A and 40.3 ± 4.5o(32.8°～50.7°) in group B.Moreover,40/40 of group A and 38/40 of group B were in the Lewinnek's inclination safe zone(P＞0.05),without significant differences between the two groups.Conclusion It is practical and reliable to decide the acetabular component orientation using the lateral position instrument and reference angle on the wall.

Objective To analyze the feasibility of using walking indicators to estimate other physical activity data,so as to provide evidences for the application of using walking monitoring tools to comprehensively assess the daily physical activity level.Methods Eighty participants were assessed 7 kinds of physical activities through wearing Cosmed K4b2 portable indirect calorimetry system and Actigraph GT3X accelerometer simultaneously.The indirect calorimetry was used as the criterion for measuring energy expenditure to develop individual equations using the vector magnitude (VM) as the independent variable.Then all participants were randomly divided into an experimental group(n=60) and a validation group (n=20).Omron HJ-113 pedometer and GT3X were then simultaneously worn to monitor their daily physical activities,with the wearing time of 3～4 days for the experimental group and 7 days for the validation group.Physical activity data were calculated using the individual equations.The correlation between walking indicators and the other physical activity data was analyzed in the experimental group,and the indicators of high correlation and application value were selected to develop equations to predict physical activity indicators.Then the data of the validation group were used to validate these equations.Results The correlation coefficients between daily steps and the moderate-to-vigorous physical activity(MVPA) time,MVPA volume,MVPA10 time and MVPA10 volume were 0.723,0.730,0.681 and 0.677 respectively(P＜0.01 for all).The correlation coefficient of the daily aerobic walking time to MVPA10 time and MVPA10 volume were 0.752 and 0.759 respectively(P＜0.01 for both).Six equations were developed based on these correlations(r2=0.55～0.63),and paired t test showed that there were no significant differences between the physical activity data predicted using these equations and the data measured by GT3X(P＞0.05).Moreover,Bland-Altman plot showed there was little predicted error for the 6 equations.Conclusion Walking indicators can indirectly reflect the overall physical activity level,and the equations developed in this study can be used to monitor the physical activity of larger samples.

Objective To investigate the effect of acute exercises of different intensities on the "browning" of epididymal white adipose tissue(WAT) in rats.Methods Thirty Sprague-Dawley male rats were randomly divided into a control group(C,n=6) and an exercises group(E,n=24).Rats in group E were further randomly divided into a moderate intensity exercise (EM,n=12,V=15 m/min) group and a high intensity intermittent exercise(EH,n=12,V=35 m/min,6min's exercises followed by 5 min's rest,repeating 3 times) group.Right after and 6 hours after the acute exercises,the epididymal WAT was taken,and the fibronectin type Ⅲ domain-containing 5 protein(FNDC5) and the uncoupling protein 1(UCP-1) mRNA were detected using RT-qPCR,while the level of FNDC5 and UCP-1 protein was evaluated using Western Blotting.Results Right after the acute exercises,compared with group C,the level of FNDC5 mRNA in group EH increased significantly (P＜0.01),while that of UCP-1 mRNA in group E decreased immediately(P＜0.05) but increased significantly six hours later(P＜0.05).Compared with group C,the level of FNDC5 in groups EM and EH tended to rise,and that of group EM increased significantly(P＜0.05).Compared with group C,the level of UCP-1 in group EM and EH had the tendency to rise,and it increased significantly immediately after exercises in group EH (P＜0.05).Conclusion The acute exercise at different intensities can promote the level of FNDC5 and UCP-1 in epididymal white adipose tissue,"browning" and heat production from fat issues.The level of UCP-1 mRNA increased significantly at 6 hours after exercises,while that of FNDC5 mRNA increased most immediately after the high-intensity intermittent exercises.

Objective To determine the effect of hypoxia conditions on the expression of autophagyrelated genes including P62,LC3 and Beclin-1 in the gastrocnemius muscles of rats with alimentary obesity and the possible mechanism of cellular autophagy induced by hypoxia exercises.Methods The model of rats with alimentary obesity was induced in Sprague-Dawley rats using high-fat diet.Then the obese rats were randomly divided into a control(C) group,a hypoxia-exercises-for-1-week(E1) group,a hypoxia-exercises-for-2-weeks (E2) group,a hypoxia-exercises-for-3-weeks (E3) group and a hypoxia-exercises-for-4-weeks(E4) group,each of 10.The rats were exposed to the environment where the simulated hypoxia was of about 13.6％ oxygen concentration(about the oxygen concentration at an actual altitude of 3,500 m),and underwent treadmill running with the speed at 20 m/min on a slope of 0 gradient every day,five days a week.After the last training,the rats were killed and sampled.The RT-PCR was used to detect the level of P62,LC3 and Beclin-1 mRNA and Western Blotting was conducted to examine the changes of protein P62 and LC3 before and after the intervention.Results Compared with group C,the expression of Beclin-1 mRNA in group E1,E2 and E3 increased significantly(P＜0.05),while the expression of protein Beclin-1 decreased significantly in group E2.The expression of protein Beclin-1 of group E2 and E3 was significantly lower than that of group E4,but there were no significant differences between group E2 and E3.Compared with group C,the relative expression of P62 mRNA in group E1 and E2 increased significantly(P＜0.05,P＜0.01),with that of group E2 significantly higher than group E1 (P＜0.05).Moreover,the relative expression of P62 mRNA in group E3 was significantly lower than that of E2(P＜0.01),and that of group E4 was significantly higher than group C,E1 and E3(P＜0.01).The relative expression of protein P62 in the obese rats in group E3 was significantly higher than that of group E2(P＜0.05).The relative expression of LC3 mRNA in group E2,E3 and E4 was significantly higher than that of group C(P＜0.01).Moreover,there were no significant differences in LC3-Ⅱ/LC3-Ⅰ protein among the five groups.Conclusion Hypoxia exercise can significantly enhance the relative expression of autophagy genes,and promote,to some extent,the autophagy.However,the transcription of autophagy genes does not happen synchronically with the synthesis of autophagy proteins.Moreover,an increase in autophagy in the skeletal muscle can be seen in the first two weeks of hypoxia exercises,followed by a gradual decrease with time prolonged,which may be the result of the gradual adaptation to hypoxia stimulation of the body.

Objective To discuss the effect of the electric stimulation on the free radicals and Nrf2 signaling pathway in skeletal muscle myoblasts(C2C12) of mice.Methods After 6 days of differentiation,skeletal muscle myoblasts(C2C12) cells of mice were randomly divided into a control group and an electrical stimulation group.The control group was not stimulated,while the electrical group was stimulated 30,45,60,75,90,120 and 150 minutes respectively with the electrical parameter as 20 ms,45 V and 5 Hz.The reactive oxygen species(ROS),glutathione peroxidase(GSH-Px) and nuclear factor E2 related factor 2(Nrf2) protein expression in C2C12 muscle tubes were determined.Results Compared with the control group,the amount of ROS produced in the C2C12 muscle tube increased significantly in the stimulation group(P＜0.05),except those stimulated for 30 and 150 minutes,with greatest increase for those stimulated for 60 and 120 minutes(P＜0.01).Compared with the control group,the activity of GSH-Px and the expression of Nrf2 nuclear protein increased significantly in all the stimula tion group(P＜0.05),except those stimulated for 30 minutes and with the greatest increase for those stimulated for 75 and 150 minutes(P＜0.01).Conclusion The electrical stimulation of 45 V,20 ms and 5 Hz can cause oxidative stress in the C2C12 muscle tube.Based on the variation of ROS production with the time of electric stimulation,it is found that only when ROS increases to a certain amount,can it activate the Nrf2 signaling system and related genes to make the GSH-Px play an antioxidant role.However,with the increase of stimulation time,the anti-oxidative ability decreases slightly,and then it continues to maintain its high level.

Objective To explore the effect of the temperature-sensitive hydrogel and platelet-rich plasma(PRP)complex on the healing of anterior cruciate ligament (ACL)partial tear in a rat model.Method PRP was processed according to an established method and then mixed with poly(ethylene glycol)monomethyl ether and poly(lactic-co-glycolic acid)(mPEG-PLGA).A total of 110 right knees of Sprague-Dawley male rats (12-week old)were included and randomly divided into a healthy control group (n=10),a lesion control group(n=60)and a study group(n=40).The saline and mPEG-PLGA-PRP complex was applied at the lesion site respectively.Samples were harvested 0,2 weeks and 6 weeks post-operatively and the histological and biomechanical changes were observed and compared among the 3 groups.Results Histologically,at 6 weeks after surgery,the torn ACL of the study group had been partially healed,with decreased number of inflammatory cells and new fibrous tissues and micro-vessels appearing.The ligament maturity index revealed a significantly higher score in the study group than the lesion control group(20.6 ± 4.9 vs.4.7 ± 1.0,P＜0.01).Biomechanically,at 6 weeks after surgery,the tensile strength of the study group was significantly higher than the contro] groups(52.7 ± 11.2 vs.30.3 ± 8.8,P＜0.05).Conclusion At six weeks after surgery,the mPEG-PLGA-PRP complex can enhance the healing of ACL partial tear,ahhough the ligament was not recovered to the norma] state.

Objective To explore the influence of visual searching training on attentional bias and stress response of athletes,in order to make guidance for their attention training before competition.Method Thirty-two athletes were given the visual searching training once every two days for 4 weeks.Before and after the training,the attention behavior of athletes was evaluated using the dot-probe task,and the stress response in stressful condition was evaluated using the rating of perceived exertion and heart rate variability(HRV).Result After the visual searching training,less stress,anxiety level and attention to negative information were observed in the stressful condition.Moreover,a decrease was also found in the ratio between low frequency and high frequency,and the low frequency normalized of HRV,while an increase was found in the high frequency normalized.Conclusion Visual searching training can lower the stress response and negative attentional bias for athletes in stressful condition.

Objective To explore the functional improvement of dancers' sensorimotor system after years of dance training.Methods Twenty-three dancers(the dance group) of more than 6 years of dancing experience and twenty-one college students (the control group) without any dance experience were recruited in this study.Then the resting state functional magnetic resonance imaging(RS-fMRI) was conducted for both groups and the data were collected.Regional homogeneity (ReHo),fractional amplitude of low frequency fluctuation (fALFF) and functional connectivity (FC) were compared between the two groups.Results Compared to the control group,significant increase was observed in the ReHo of the bilateral postcentral gyruses,the left superior temporal gyrus,the right precentral gyrus and the middle occipital gyrus and fALFF in the bilateral precentral gyruses of the dance group.Moreover,the connection between the right precentral gyrus and left precentral gyrus and the FC between the right precentral gyrus and bilateral postcentral gyrus enhanced significantly in the dance group compared to the control group.Conclusions The functional modulation of dancers' sensorimotor system may be associated with the long-term dancing experience,which may lead to the changes in action perception,memory processing,motor learning and movement control to enhance the formation of the mode to observe,implement and adjust complex actions.Our study has provided a supporting evidence for dancing-induced brain plasticity.

Objective To assess the impact of maximal fat oxidation intensity(FATmax) exercise on arterial stiffness in overweight/obesity young men.Method Thirty two overweight/obesity young men (BMI≥25 kg/m2) without the habit of doing exercises,were divided into an exercise group (n=16) and a control group (n=16) randomly.The exercise group completed a 12-week walk/run(FATmax intensity,3-5 times/week,40-60 min/time) intervention,while the control group maintained normal life style without regular exercise.The body composition,cardiopulmonary function (VO2max),C reactive proteins (CRP) and blood hemodynamic were measured,and the brachial-ankle pulse wave velocity(baPWV) was observed to assess the arterial stiffness before and after the 12-week intervention.Results Significant decrease was observed in the average weight,body mass index,body fat mass,body fat percentage,baPWV,CRP,platelet/lymphocyte ratio (PLR) and neutrophil/lymphocyte ratio (NLR) (P＜0.05),while significant increase was found in the average VO2max and HDL-C(P＜0.05) after the training.After the intervention,the change in baPWV(△) was positively associated with △ CRP(r=0.604),△ NLR(r=0.535) and △ WBC (white blood count) (r=0.406) (P＜0.05,n=32),but negatively correlated with △ VO2max (r=-0.660,P＜0.05,n=32).Conclusion FATmax intensity aerobic exercise is effective to downregulate the inflammation,and improve aerobic fitness and vascular function.However,the potential mechanism of arterial stiffness improvement following exercise needs further study.