Lowering minimum eye height to increase peak knee and hip flexion during landing

The purpose was to determine the effect of lowering minimum eye height through an externally focused object on knee and hip flexion and impact forces during jump-landing. Kinematics and ground reaction forces were collected when 20 male and 19 female participants performed jump-landing trials with their natural minimum eye height, and trials focusing on lowering their minimum eye height to an external object, which was set at 5% or 10% of standing height lower. Participants demonstrated decreased minimum eye height and increased peak knee and hip flexion during early-landing and stance phase when focusing on lowering eye height to the external object (p \u3c 0.01). Peak vertical ground reaction forces during early-landing also decreased for the greater force group (p \u3c 0.001). Jump-landing training through manipulating eye height provides a strategy that involves an external focus and intrinsic feedback, which may have advantages in promoting learning and practical application

PO-228 Effects of Different Cryotherapy Models on Timing Sequence Recovery of Exercise Induced Muscle Damage in Middle and Long Distance Runners

Objective Exercise induced muscle damage (EIMD) is one common physiological phenomenon in competitive sports and mass sports. Water immersion recovery and whole body cryotherapy (cryostimulation) (WBC) has become one of the fast recovery methods adopted by high level athletes in the world. The aim of this study was to compare the water immersion recovery and WBC from timing sequential recovery on EIMD, subjective scales, biochemical indicators, exercise performance indicators. Methods Twelve middle and long distance runners from Beijing Sport University were recruited in this study (exercise performance is secondary level in China). All participants performed four models in four weeks which included rest control (CON), cold water immersion(CWI), contrast water therapy (CWT) and whole body cryotherapy (cryostimulation) (WBC) separated by one week. The subjects needed to complete the EIMD exercise program, includes two parts: the treadmill running and the jump step. The individual speed of treadmill running was based on the individual VO2max. running including 5 sets and total time is about 90 min. Every set consist of 6 min flat running, 6 min uphill running and 6 min downhill running. The speed of the treadmill was stable in different stages. The slope of the uphill running is（＋6,＋5,＋4,＋3,＋2）, and the slope of downhill running is (-8, -7, -6, -5, -4). The jump was performed 20 times separated by 30 s via special step ( height is 40 cm) . After the EIMD exercise program, the subjects were treated with different recovery methods immediately after exercise, 24 h, 48 h, 72 h after exercise, while CON group received no intervention. The CWI group was immerged in 15 °C cold water for 12min, and the CWT groups was immerged in 15°C cold water for 1min and 38°C hot water for 1min with 6 cycles. The whole body cryotherapy (cryostimulation) group was immerged in special chamber (-110—-140℃）for 3 min. The three interventions were immerged body to the position of shoulders. The indexes including subjective scales (VAS scale, RPE scale, Borg scale, WHO deep sleep scale, PQSI scale), biochemical indicators (creatine kinase, lactate dehydrogenase, myoglobin, interleukin-6, C reactive protein, SICAM-1), exercise performance indicators ( vertical jump height, grip, running distance). The indexes was collected in different periods (i.e. Before exercise, immediately after exercise,Post1h, Post 24h, Post 48h, Post 72h, Post 96h after exercise etc.). Results  (1) Subjective scales. From results of VAS scale, RPE scale, and Borg scale, the WBC had best recovery effects than the other three interventions (P<0.05).  The recovery effect of the CWI group was similar with the CON group. From results of WHO deep sleep scale and PQSI scale, the WBC group had better recovery effects than CON group (P<0.05). (2) Biochemical indicators. From results of CK, Mb and SICAM-1, the WBC group had better recovery effect than the other three groups (P<0.05). In the LDH, the WBC group had similar effects with the CWT group (P>0.05). From results of CRP and IL-6, the WBC group had better recovery effects than the other three groups (P<0.05).（3）Exercise performance indicators. From results of vertical jump, WBC had lower decrease than the other three groups (P<0.05).  From results of the grip, of the WBC and CWT groups have significant retentive effects than CON group (P<0.05), but there was no significant difference between CON and CWI groups (P>0.05). Conclusions (1)Through combine the treadmill running and the jump step exercise program,Can effectively lead to human body appear the EIMD. (2)WBC has positive effects on the subjective scale, biochemical indicators, exercise performance indicators associated with EIMD.For middle and long distance runners EIMD,compared with CWI CWT,WBC effect is better.(3) CWI and CWT has a positive effect on some subjective scales, biochemical indicators, and exercise performance indicators related to EIMD. However, the positive effect of CWI and CWT is lower than WBC in the extent of action and timing sequence. (4)For the middle and long distance runners EIMD timing sequence recovery effects,WBC have better effects,Followed by CWT , CWI  effect is not significant

PO-246 Effects of Different Methods of Precooling on Sub-maximal Intensity Exercise in Heat and High Humidity

Objective This study aimed to investigate the influence of using different precooling measures on the capacity of competition and the exercise performance in hot and humidity environment. The most effectual means of precooling will be recommended to help coaches and athletes to improve the ability and performance in training and matches Methods Ten male football (Rugby) players who came from the rugby team totally completed four experimental conditions in hot/humid conditions (38℃, 50% humidity). Initially, a 30-min precooling period consisting of either nothing to control (CONT, C); wearing cooling vest (4℃, V); ingesting of ice beverage (2.3 ml /kg of 4℃, I); or the mix method of combination of V and I (V+I, M). Following this, sub-maximal exercise (80% VO2max) of treadmill test occurred, until athletes exhausted Results The running distance of M and V and I have a significant increase (P≤0.05) than CONT. The peak oxygen uptake of exhaustion was no significant difference between each other. After exercise, the change rate of heart rate ratio of M compared with CONT has a very significant decrease (P≤0.01). The core temperature of M and CONT has a significant increase (P≤0.05) in comparison. The surface temperature of I and M and V comparison with CONT has a very significant increase (P≤0.01). When participants exhaust, the RPE of M in comparison with CONT had significantly lower (P≤0.05). The RPB and the rating of thermal sensation of each condition were no significant difference. After exercise, the blood lactic concentration of each ones was no significant difference Conclusions In hot and humidity condition, precooling has a promoting effect on the sub-maximal exercise. Precooling measures could improve the exercise performance and maintain the stability of functional status and physiology, especially the mix method. &nbsp

Metformin Uniquely Prevents Thrombosis by Inhibiting Platelet Activation and mtDNA Release

Thrombosis and its complications are the leading cause of death in patients with diabetes. Metformin, a first-line therapy for type 2 diabetes, is the only drug demonstrated to reduce cardiovascular complications in diabetic patients. However, whether metformin can effectively prevent thrombosis and its potential mechanism of action is unknown. Here we show, metformin prevents both venous and arterial thrombosis with no significant prolonged bleeding time by inhibiting platelet activation and extracellular mitochondrial DNA (mtDNA) release. Specifically, metformin inhibits mitochondrial complex I and thereby protects mitochondrial function, reduces activated platelet-induced mitochondrial hyperpolarization, reactive oxygen species overload and associated membrane damage. In mitochondrial function assays designed to detect amounts of extracellular mtDNA, we found that metformin prevents mtDNA release. This study also demonstrated that mtDNA induces platelet activation through a DC-SIGN dependent pathway. Metformin exemplifies a promising new class of antiplatelet agents that are highly effective at inhibiting platelet activation by decreasing the release of free mtDNA, which induces platelet activation in a DC-SIGN-dependent manner. This study has established a novel therapeutic strategy and molecular target for thrombotic diseases, especially for thrombotic complications of diabetes mellitus

Successful interventional management of postoperative hemorrhage in total arch replacement of type A aortic dissection

We reported a 48-year-old male patient with postoperative hemorrhage. Given his frailty, emergent interventional procedures were successfully performed and the end of the left subclavian artery was embolized by four coils. Our report provided a new therapeutic approach regarding the frail patients presenting postoperative hemorrhage

Analysis of circulatory mitochondrial DNA level after cardiac surgery with cardiopulmonary bypass and potential prognostic implications

Our research letter found that circulatory mtDNA level increased after the end of CPB and positive correlations between mtDNA and peak CRP level, peak BNP level, and peak PCT level, which revealed the prognostic role of perioperative circulatory mtDNA level in patients who underwent cardiopulmonary bypass

A Metabolomics-Based Study on NMDAR-Mediated Mitochondrial Damage through Calcium Overload and ROS Accumulation in Myocardial Infarction

Background: Coronary artery disease is a leading public health problem. However, the mechanisms underlying mitochondrial damage remain unclear. The present study verified and explored the novel mechanisms underlying ischemic injury based on a metabolomic analysis. Methods: Mouse models of acute myocardial infarction were established, and serum samples were collected for targeted liquid chromatography with tandem mass spectrometry analysis. Based on metabolomic analyses, the N-methyl-d-aspartic acid receptor (NMDAR)–related calcium transporting signaling pathway was selected. Primary cardiomyocyte cultures were used, and N-methyl-d-aspartic acid (NMDA) was used as an agonist to confirm the role of NMDAR in ischemic injury. In addition, Bax, Bcl-2, mitochondrial calcium, potential, and mitochondrial reactive oxygen species accumulation were used to explore the role of NMDAR in mitochondrial damage–induced apoptosis. Results: Glutamate-related metabolism was significantly altered following in acute myocardial infarction. NMDA induces apoptosis under hypoxic conditions NMDAR was translocated to the mitochondrial-related membrane after activation, and its mitochondrial expression was significantly increased (p < 0.05). Mitochondrial damage–induced apoptosis was significantly inhibited by a selective NDMAR antagonist (p < 0.05), while Bax expression was remarkably decreased and Bcl-2 expression was increased (p < 0.05). To further explore the mechanism of NMDAR, mitochondrial calcium, membrane potential, and reactive oxygen species were detected. With NMDAR inhibition under hypoxic conditions, mitochondrial morphology and function were preserved (p < 0.05). Conclusions: Our metabolomic study identified NMDAR as a promising target. In conclusion, our study provides solid data for further studies of the role of NMDAR in cardiovascular diseases and a promising target to interfere with apoptosis in acute myocardial infarction