Objective By exploring changes of six degrees of freedom(6DOF)kinematics of the knee joint during extra weight bearing of the body trunk,the influence of extra weight on knee joint movement patterns was studied.Methods A total of 24 healthy subjects were recruited to walk/run on a treadmill at four speeds under two states:self-weight and wearing a 16 kg vest,and gait analysis was conducted.A three-dimensional(3D)portable knee kinematics analysis system based on infrared stereophotography was used to capture 6DOF movement trajectory data of the tibia relative to the femur.Results Compared to the self-weight state,when additional trunk weight was added,the knee external rotation angle was reduced at 3.6 km/h speed(1.4°-2.1°)and 5.4 km/h speed(2.2°-2.7°);the knee internal rotation angle was reduced at 10.8 km/h speed(2.1°-4.2°);the knee flexion angles was increased significantly at the speed of 3.6 km/h(1.5°-1.8°),9 km/h(1.6°-3.3°)和 10.8 km/h(1.9°-3.1°);the knee adduction angle increased at 5.4 km/h speed(0.5°-0.6°),and decreased at 10.8 km/h speed(0.9°-1.3°).At 10.8 km/h speed,the distal knee displacement(0.2-0.4 mm)was increased,and the lateral knee displacement(0.1-0.2 mm),and anterior knee displacement(0.2-0.3 mm)were significantly reduced.Conclusions The 6DOF kinematics of human knee is significantly affected by the extra trunk weight.Performance is also different at lower and higher speeds.It is suggested that there may exist a hidden injury in military training,and this study provides a kinematic basis for the occurrence of sports injury.

Objective By exploring changes of six degrees of freedom(6DOF)kinematics of the knee joint during extra weight bearing of the body trunk,the influence of extra weight on knee joint movement patterns was studied.Methods A total of 24 healthy subjects were recruited to walk/run on a treadmill at four speeds under two states:self-weight and wearing a 16 kg vest,and gait analysis was conducted.A three-dimensional(3D)portable knee kinematics analysis system based on infrared stereophotography was used to capture 6DOF movement trajectory data of the tibia relative to the femur.Results Compared to the self-weight state,when additional trunk weight was added,the knee external rotation angle was reduced at 3.6 km/h speed(1.4°-2.1°)and 5.4 km/h speed(2.2°-2.7°);the knee internal rotation angle was reduced at 10.8 km/h speed(2.1°-4.2°);the knee flexion angles was increased significantly at the speed of 3.6 km/h(1.5°-1.8°),9 km/h(1.6°-3.3°)和 10.8 km/h(1.9°-3.1°);the knee adduction angle increased at 5.4 km/h speed(0.5°-0.6°),and decreased at 10.8 km/h speed(0.9°-1.3°).At 10.8 km/h speed,the distal knee displacement(0.2-0.4 mm)was increased,and the lateral knee displacement(0.1-0.2 mm),and anterior knee displacement(0.2-0.3 mm)were significantly reduced.Conclusions The 6DOF kinematics of human knee is significantly affected by the extra trunk weight.Performance is also different at lower and higher speeds.It is suggested that there may exist a hidden injury in military training,and this study provides a kinematic basis for the occurrence of sports injury.

BACKGROUND:In recent years,as the popularity of long-distance fitness running continues to rise,more research progress has been made on related scientific issues.Among them,the landing pattern of long-distance running is an important biomechanical research hotspot at the level of running technique. OBJECTIVE:Using CiteSpace to visualize and analyze the relevant literature,the article sorts through the last decade's literature on the subject to identify the current state,hot spots,and trends in the footprint as well as to further discuss the main research hotspots of the foot strike pattern from a biomechanical perspective. METHODS:"Foot strike pattern,""Rearfoot strike,""non-Rearfoot strike,""Forefoot strike"and"Midfoot strike"were used as keywords to search the Web of Science Core Collection database. RESULTS AND CONCLUSION:A total of 896 relevant papers were finally included.The number of articles published in a year showed an overall upward trend.The top three countries in terms of the number of publications were the United States,China and the United Kingdom;the top three institutions were Harvard University,Shanghai University of Sports and the University of Massachusetts;and the top three authors were Davis Irene S,Hamill Joseph and Fu Weijie.The keywords"barefoot running,runner,injury,footing pattern,kinesiology"appear more frequently,and the keyword clusters include"energy cost,loading rate,footing pattern,risk factors,gait analysis",and the relevant research still continues to be hot to this day.After analyzing the above data in detail,we found that the overall research intensity of foot strike pattern has remained stable in recent years,and the hotspot mainly focuses on the biomechanical research of foot strike pattern;the trend of this kind of research focuses on the influence and adaptability of different strike patterns(forefoot strike and rearfoot strike)on long-distance runners(barefoot,shoes,distance,speed,injury risk,running economy and energy consumption,etc.).Therefore,there is no"standardized optimal landing,"but there may be"individualized optimal landings."It is suggested that researchers should select the optimal landing pattern and running technique strategy according to their own habitual way,movement pattern characteristics,exercise level and task attributes.

OBJECTIVETo primarily evaluate the effects of ulinastatin on immune function of patients with severe burn injury.

METHODSForty patients with severe burn admitted to our ward from March 2013 to October 2015, conforming to the study criteria, were divided into conventional treatment group (CT, n=20) and ulinastatin treatment group (UT, n=20) according to the random number table and patient's consent. After admission, patients in group CT received antishock treatment, antibiotic treatment, debridement, skin grafting, and nutrition support, etc. On the basis of the above-mentioned treatment, patients in group UT received intravenous drip of ulinastatin from first day after admission twice a day, with a dosage of 8×10(5) U every time, for 7 days in addition. Peripheral venous blood samples were collected from patients in groups CT and UT on post treatment day (PTD) 1, 3, 5 and 7, respectively. Twenty healthy volunteer were selected as health control group (HC), and peripheral venous blood samples were collected on the first day of the study. Percentage of CD4(+) CD25(+) regulatory T lymphocytes (Tregs) was determined by flow cytometer. The proliferative activity of T lymphocytes was detected by microplate reader (denoted as absorbance value). Content of interleukin 2 (IL-2) in culture supernatant of T lymphocytes, and content of IL-4 and γ interferon (IFN-γ) in serum were detected by enzyme-linked immunosorbent assay. Expression of human leukocyte antigen-DR (HLA-DR) on CD14(+) monocytes was determined by flow cytometer. Data were processed with analysis of variance for repeated measurement, chi-square test, and LSD-t test.

RESULTS(1) Compared with that of volunteer in group HC, the percentage of CD4(+) CD25(+) Tregs of patients in group CT was significantly increased from PTD 1 to 7 (with t values from 13.303 to 26.043, P values below 0.01). Compared with that in group CT, the percentage of CD4(+) CD25(+) Tregs of patients in group UT was significantly decreased on PTD 5 and 7 (with t values respectively 8.317 and 15.071, P values below 0.01). (2) The proliferative activity of T lymphocytes of patients in group CT on PTD 1, 3, 5, and 7 was respectively 0.71±0.11, 0.61±0.15, 0.54±0.12, and 0.67±0.17, which was significantly lower than that in group HC (1.21±0.22, with t values from 8.686 to 11.957, P values below 0.01). The proliferative activity of T lymphocytes of patients in group UT on PTD 3, 5, and 7 were respectively 0.81±0.11, 0.85±0.14, and 1.08±0.13, which was significantly higher than that in group CT (with t values from 4.808 to 8.568, P values below 0.01). (3) Compared with those of volunteer in group HC, content of IL-2 in culture supernatant of T lymphocytes of patients in group CT was significantly decreased from PTD 1 to 7 (with t values from 8.073 to 9.288, P values below 0.01), content of IL-4 in serum of patients in group CT was significantly increased from PTD 1 to 7 (with t values from 18.926 to 41.451, P values below 0.01), and content of IFN-γ in serum of patients in group CT was significantly decreased from PTD 1 to 7 (with t values from 4.543 to 27.659, P values below 0.01). Compared with those in group CT, content of IL-2 in culture supernatant of T lymphocytes of patients in group UT was significantly increased from PTD 3 to 7 (with t values from 6.507 to 8.869, P values below 0.01), content of IL-4 in serum of patients in group UT was significantly decreased from PTD 3 to 7 (with t values from 6.922 to 8.843, P values below 0.01), and content of IFN-γ in serum of patients in group UT was significantly increased on PTD 5 and 7 (with t values respectively 5.369 and 13.521, P values below 0.01). (4) The percentages of CD14(+) monocytes with positive expression of HLA-DR of patients in group CT on PTD 1, 3, 5, and 7 were respectively (28±6)%, (25±7)%, (25±7)%, and (39±10)%, which were significantly lower than the percentage of volunteer in group HC [(87±8)%, with t values from 16.323 to 25.645, P values below 0.01]. The percentages of CD14(+) monocytes with positive expression of HLA-DR of patients in group UT on PTD 3, 5, and 7 were respectively (40±6)%, (42±9)%, and (49±10)%, which were significantly higher than those in group CT (with t values from 3.071 to 7.324, P values below 0.01).

CONCLUSIONSOn the basis of CT, additional ulinastatin intervention can decrease CD4(+) CD25(+) Tregs percentage, improve the immune function of T lymphocytes and T helper cells, and increase expression of HLA-DR on CD14(+) monocytes of patients with severe burn injury, thus improve the immune function of patients.

Burns ; drug therapy ; immunology ; Cells, Cultured ; Debridement ; Enzyme-Linked Immunosorbent Assay ; Glycoproteins ; therapeutic use ; Humans ; Interferon-gamma ; blood ; Interleukin-2 ; metabolism ; Interleukin-4 ; blood ; Monocytes ; immunology ; Skin Transplantation ; T-Lymphocytes, Regulatory ; immunology

OBJECTIVETo observe the effects of ulinastatin on immune function of splenic CD4(+) T lymphocytes and CD4(+) CD25(+) regulatory T lymphocytes (Tregs) and content of high mobility group box 1 (HMGB1) in peripheral blood of severely burned rats, and to analyze the possible mechanisms.

METHODSNinety-six male SD rats were divided into sham injury group, burn group, and ulinastatin group according to the random number table, with 32 rats in each group. Rats in sham injury group were sham injured on the back by immersing in 37 ℃ warm water for 12 s. Rats in burn group and ulinastatin group were inflicted with 30% total body surface area full-thickness scald (hereinafter referred to as burn) on the back by immersing in 94 ℃ hot water for 12 s. Immediately after injury, rats in each group were intraperitoneally injected with saline (40 mL/kg), meanwhile rats in ulinastatin group were intraperitoneally injected with ulinastatin (4×10(4) U/kg), once per 12 h, till post injury hour 72. Eight rats of each group were respectively selected on post injury day (PID) 1, 3, 5, and 7 to collect abdominal aortic blood samples. Serum content of HMGB1 was detected by enzyme-linked immunosorbent assay (ELISA). And then, rats of the 3 groups were sacrificed immediately to collect spleens and separate CD4(+) CD25(+) Tregs and CD4(+) T lymphocytes. Flow cytometer was used to detect positive expression rates of cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) and forkhead-winged helix transcription factor p3 (Foxp3) in CD4(+) CD25(+) Tregs. Content of IL-10 in culture supernatant of CD4(+) CD25(+) Tregs, and content of interleukin 2 (IL-2), IL-4, and γ interferon (IFN-γ) in culture supernatant of CD4(+) T lymphocytes was detected by ELISA. The proliferative activity of CD4(+) T lymphocytes was determined by microplate reader. The sample number of above-mentioned experiments was 8 at each time point in each group. Data were processed with analysis of variance of factorial design and LSD test.

RESULTS(1) Compared with that in sham injury group, serum content of HMGB1 of rats in burn group was significantly increased from PID 1 to 7 (with P values below 0.01). Compared with that in burn group, serum content of HMGB1 of rats in ulinastatin group was significantly decreased from PID 1 to 7 (with P values below 0.01). (2) Compared with those in sham injury group, the positive expression rates of CTLA-4 and Foxp3 in CD4(+) CD25(+) Tregs and content of IL-10 in culture supernatant of CD4(+) CD25(+) Tregs of rats in burn group were significantly increased from PID 1 to 7 (with P values below 0.01), peaking on PID 3 [(65±10)%, (76±10)%, and (28.2±4.4) pg/mL respectively]. These 3 indexes of rats in sham injury group on PID 3 were (45±7)%, (46±7)%, and (11.2±2.3) pg/mL respectively. Compared with those in burn group, the positive expression rates of CTLA-4 and Foxp3 in CD4(+) CD25(+) Tregs and content of IL-10 in culture supernatant of CD4(+) CD25(+) Tregs of rats in ulinastatin group were significantly decreased from PID 1 to 7 (P<0.05 or P<0.01), reaching the nadir on PID 7 [(43±6)%], PID 1 [(50±8)%], and PID 7 [(12.4±3.4) pg/mL] respectively. These 3 indexes of rats in burn group on PID 7, 1, and 7 were (58±8)%, (71±9)%, and (19.7±2.8) pg/mL respectively. (3) Compared with those in sham injury group, the content of IL-2 and IFN-γ in culture supernatant of CD4(+) T lymphocytes of rats was significantly decreased, while the content of IL-4 in culture supernatant of CD4(+) T lymphocytes of rats was significantly increased in burn group from PID 1 to 7, with P values below 0.01. Compared with that in burn group, the content of IL-2 and IFN-γ in culture supernatant of CD4(+) T lymphocytes of rats was significantly increased, while the content of IL-4 in culture supernatant of CD4(+) T lymphocytes of rats was significantly decreased in ulinastatin group from PID 1 to 7, P<0.05 or P<0.01. (4) Compared with that in sham injury group, the proliferative activity of CD4(+) T lymphocytes of rats in burn group was significantly decreased from PID 1 to 7 (with P values below 0.01). Compared with that in burn group, the proliferative activity of CD4(+) T lymphocytes of rats in ulinastatin group was significantly increased from PID 1 to 7 (with P values below 0.01).

CONCLUSIONSUlinastatin can weaken the immunosuppressive function mediated by splenic CD4(+) CD25(+) Tregs in severely burned rats, and improve proliferative function and secretory function of splenic CD4(+) T lymphocytes, which may be attributed to the inhibiting effect of ulinastatin on the release of HMGB1 in large amount.

Animals ; Burns ; drug therapy ; CTLA-4 Antigen ; metabolism ; Enzyme-Linked Immunosorbent Assay ; Flow Cytometry ; Forkhead Transcription Factors ; metabolism ; Glycoproteins ; pharmacology ; HMGB1 Protein ; blood ; Interferon-gamma ; metabolism ; Interleukin-10 ; metabolism ; Interleukin-2 ; metabolism ; Interleukin-4 ; metabolism ; Male ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Spleen ; drug effects ; T-Lymphocytes, Regulatory ; cytology ; drug effects

[ABSTRACT]AIM:ToobservehowfarnesoidXreceptor(FXR)functionedinconcanavalinA(ConA)-induced hepatitis (CIH) and the regulation of FXR-thyrotropin embryonic factor (TEF) pathway.METHODS:C57BL/6 mice were injected with Con A to induce hepatitis .The expression of FXR and TEF in the liver specimens was determined by qRT-PCR and Western blotting .The concentrations of serum ALT/AST and inflammatory cytokines IFN-γ, TNF-α, IL-4 and IL-2 in the blood samples were tested after Con A injection .RESULTS:FXR was down-regulated in CIH mice .TEF was up-regula-ted when FXR was activated by chenodeoxycholic acid (CDCA).Activation of FXR reduced the levels of aminotransferases and inflammatory cytokines IFN-γ, TNF-α, IL-4 and IL-2 in the CIH mice induced by Con A injection .CONCLUSION:FXR activation attenuates CIH mouse liver injury and reduces inflammatory cytokines .FXR activation results in TEF up-regu-lation.The FXR-TEF pathway may play a protective role in autoimmune hepatitis .