The guardian of the genome p53 regulates exercise‐induced mitochondrial plasticity beyond organelle biogenesis

The Guardian of the Genome p53 has been established as a potent tumour suppressor. However, culminating from seminal findings in rodents more than a decade ago, several studies have demonstrated that p53 is required to maintain basal mitochondrial function [ie, respiration and reactive oxygen species (ROS) homeostasis]. Specifically, via its role(s) as a tumour suppressor, p53 intimately surveys cellular DNA damage, in particular mitochondrial DNA (mtDNA), to ensure that the mitochondrial network is carefully monitored and cell viability is upheld, because aberrant mtDNA damage leads to apoptosis and widespread cellular perturbations. Indeed, data from rodents and humans have demonstrated that p53 forms an integral component of the exercise‐induced signal transduction network regulating skeletal muscle mitochondrial remodelling. In response to exercise‐induced disruptions to cellular homeostasis that have the potential to harm mtDNA (eg, contraction‐stimulated ROS emissions), appropriate p53‐regulated, mitochondrial turnover responses prevail to protect the genome and ultimately facilitate a shift from aerobic glycolysis to oxidative phosphorylation, adaptations critical for endurance‐based exercise that are commensurate with p53's role as a tumour suppressor. Despite these observations, several discrepancies exist between rodent and human studies pinpointing p53 subcellular trafficking from nuclear‐to‐mitochondrial compartments following acute exercise. Such interspecies differences in p53 activity and the plausible p53‐mediated adaptations to chronic exercise training will be discussed herein.     

新型撑开器结合微创内固定系统内固定治疗胫骨近端骨折

背景:传统手术治疗方法治疗胫骨近端骨折对骨折部位剥离广泛,且影响局部血液循环,增加骨折延迟愈合和不愈合的发生率。近年来兴起的微创内固定系统,可以最大限度地保护局部软组织以及血液循环,为骨折愈合提供更好的条件,而新型撑开器的应用也解决了传统人手牵引复位稳定性、持久性的问题,两者的结合应用逐渐受到关注。目的:探讨新型撑开器辅助复位、微创内固定系统治疗胫骨近端骨折的疗效。方法:以2016年5月至2019年10月收治的22例胫骨近端骨折患者为研究,随机分为对照组和观察组,各11例。对照组采用传统手法复位、常规切口钢板内固定;观察组以新型撑开器辅助复位、微创内固定系统钢板内固定。试验经广州医科大学附属第五医院伦理委员会批准。结果与结论:与对照组相比,观察组患者末次随访时Rasmussen膝关节功能评分较优,术中失血量、手术用时、住院天数、开始负重时间较少,出现关节受限、骨折延迟愈合等术后并发症患者数量较少,但骨折愈合时间与对照组接近,且切口感染、内固定松动断裂等术后并发症患者数量与对照组接近。提示应用新型撑开器结合微创内固定系统内固定治疗胫骨近端骨折,可以减少手术复位时间、降低局部软组织损伤,有利于患者早期功能锻炼,减少手术后并发症。     

Influence of concurrent exercise or nutrition countermeasures on thigh and calf muscle size and function during 60 days of bed rest in women

AIM: The goal of this investigation was to test specific exercise and nutrition countermeasures to lower limb skeletal muscle volume and strength losses during 60 days of simulated weightlessness (6 degrees head-down-tilt bed rest). METHODS: Twenty-four women underwent bed rest only (BR, n = 8), bed rest and a concurrent exercise training countermeasure (thigh and calf resistance training and aerobic treadmill training; BRE, n = 8), or bed rest and a nutrition countermeasure (a leucine-enriched high protein diet; BRN, n = 8). RESULTS: Thigh (quadriceps femoris) muscle volume was decreased (P < 0.05) in BR (-21 +/- 1%) and BRN (-24 +/- 2%), with BRN losing more (P < 0.05) than BR. BRE maintained (P > 0.05) thigh muscle volume. Calf (triceps surae) muscle volume was decreased (P < 0.05) to a similar extent (P > 0.05) in BR (-29 +/- 1%) and BRN (-28 +/- 1%), and this decrease was attenuated (P < 0.05) in BRE (-8 +/- 2%). BR and BRN experienced large (P < 0.05) and similar (P > 0.05) decreases in isometric and dynamic (concentric force, eccentric force, power and work) muscle strength for supine squat (-19 to -33%) and calf press (-26 to -46%). BRE maintained (P > 0.05) or increased (P < 0.05) all measures of muscle strength. CONCLUSION: The nutrition countermeasure was not effective in offsetting lower limb muscle volume or strength loss, and actually promoted thigh muscle volume loss. The concurrent aerobic and resistance exercise protocol was effective at preventing thigh muscle volume loss, and thigh and calf muscle strength loss. While the exercise protocol offset approximately 75% of the calf muscle volume loss, modification of this regimen is needed.     

Regression of juvenile idiopathic scoliosis

For a young scoliotic boy the customary "wait and watch" management program for rapidly progressive juvenile idiopathic scoliosis was considered unsatisfactory in view of the poor prognosis. The management program devised was based on the congenital postural induction concept of scoliosis with progression accruing from mechanically induced bioengineering fatigue, cumulative molecular scissions, laxity of ligaments, and secondary bone deformation. A coexisting pelvic tilt with restricted movement of the hip and shoulder joints was overlooked initially. Possibly induced simultaneously with the scoliosis, it is considered a contributory factor in scoliosis progression and requires early diagnosis and correction. The rapid improvement in this child's spinal status achieved by physiological traction and specifically designed exercises was such that as a preventive measure the technique warrants further clinical assessment on young scoliotics.     

The mirror does not lie: Acute exercise and self-efficacy

Although acute bouts of exercise have consistently been found to enhance self-efficacy, recent evidence suggests that the exercise environment may moderate this relation. The purpose of this study was to investigate the influence of an acute bout of exercise performed in environments differing in self-evaluative potential on self-efficacy. Forty-three female undergraduates performed 20 min of aerobic exercise in front of and in the absence of a full-length mirror. Self-efficacy was assessed at 4 time points: before entry into the experimental condition, pre-exercise, postexercise, and 20 min postexercise. Results revealed that self-efficacy did not significantly change following exercise or recovery in the no mirror condition. However, the mirror condition resulted in moderate increases in self-efficacy postexercise and large increases following recovery. Results indicate that self-evaluation following exercise may increase one’s perceptions of capabilities and appear to be in contrast to past research demonstrating a negative effect of mirrors on self-efficacy.     

骨质疏松症患者运动处方及运动疗效

目的探讨运动疗法对骨质疏松症(OP)的疗效及治疗OP的运动处方。方法将26例原发性骨质疏松症(OP)患者按病情平分成A、B两组,B组的运动负荷约为A组的75%,治疗18个月后对比两组患者治疗前后腰椎的骨密度值以及两组的疗效。结果骨密度值都明显增大(P<0.01或P<0.05),并且A组的增幅大于B组;经疗效评定,A组治愈率为69.2%,好转率为23.1%,B组治愈率为38.5%,好转率为53.8%,A组的疗效优于B组(P<0.01)。结论不同运动对原发性OP患者的治疗作用及疗效有所不同;运动负荷强度影响着治疗效果。     

毒鼠强浓度在人体内变化规律研究

Objective To study the variation of blood concentration of tetramine in human body with acute tetramine intoxication treated with three different protocols and the levels in human body after discharge from the hos-pital. Methods The blood concentration of tetramine was determined by gas chromatography-mass spectrometry (GC-MS). All 101 patients of acute tetramine intoxication were divided into 3 groups (routine comprehensive treat-ment group,hemoperfusion group,blood transfusion group) according to their blood concentration of tetramine and clinical symptoms. The patients were followed up to monitor the tetramine levels in a year. Results The level of tet-famine in blood was decreased from 33.0(1.7～115.0)μg/L to 18.0(0.3～47.6)μg/L in routine comprehensive treatment group. The total decrement was 45.5 %. The level was decreased from 108.0 (54.0～290.0)μg/L to 26.0 μg/L in hemoperfusion group. The total decrement was 75.9%. The decrement was 20.0%～45.0% after each he-moperfusion. The level was slightly high after 24 h of hemoperfusion. The total decrement in blood transfusion group was 33.5%～60.0%. The level was <0.3μg/L in all 25 out-patients 1 year after their intoxication. Conclusion Routine comprehensive treatment,hemoperfusion,blood transfusion are effective in the treatment of acute tetramine intoxication. The degradation of tetramine in human body is slow.     

Microvolt T-Wave Alternans During Exercise and Pacing in Patients with Acute Myocardial Infarction

Cardiac Arrhythmias and Risk Stratification after Myocardial infarction (CARISMA) is a prospective multicenter trial designed to document the incidence of cardiac arrhythmias after acute myocardial infarction (AMI), and to assess the predictive accuracy of various arrhythmic risk markers. In this substudy of the CARISMA trial, microvolt T-wave alternans (TWA) was assessed with specific equipment 6 weeks after AMI during bicycle exercise, atrial (A) pacing, and simultaneous ventricular and atrial (V + A) pacing in 80 patients with left ventricular ejection fraction (LVEF) <40%. The agreement between the acute test results was determined by overall proportion of concordance and the kappa statistic. Sustained TWA was observed in 24, 45, and 50% of the patients during the exercise test, A pacing, and V + A pacing, respectively. The number of indeterminate TWA was significantly lower during V + A pacing (n = 7) than exercise test (n = 34). The TWA concordance rate was 71% between exercise and V + A pacing (κ= 0.53, P = 0.001), 79% between exercise and A pacing (κ= 0.54, P < 0.001), and 95% between the two pacing modes (κ= 0.89, P < 0.001). Patients with positive TWA in all tests had lower LVEF (28 ± 7% vs 35 ± 9%, P < 0.01) and wider QT dispersion (99 ± 44 ms vs 67 ± 38 ms, P < 0.01) than those with inconsistent test result. The low number of indeterminate tests and high concordance between the test results indicate that V + A pacing may provide a valuable means to assess TWA in patients who cannot complete the exercise test.     

运动及饮食疗法对代谢综合征患者及高危者的治疗作用

目的：探讨运动训练及饮食控制对以超重或肥胖为基础的代谢综合征患者及高危者的治疗改善作用。方法：以超重或肥胖为基础的代谢综合征患者及高危者共197例．进行6周运动训练及饮食控制治疗．观察治疗后代谢综合征各组成成分的变化。结果：治疗后受试者具有的代谢综合征组成成分的个数明显减少（P〈0．001）。体重、BMI、收缩压、舒张压、甘油三酯治疗后明显降低（P〈0．05），高密度脂蛋白胆固醇明显提高（P=0．001）。患者组改善较高危组明显（P〈0．001）。结论：对于以肥胖或超重为基础、年龄较轻的代谢综合征患者和高危者，短期低能量饮食配合中等强度规律运动．可以取得较好的治疗效果。     

富氧水对高原人体血液流变学的干预

目的探讨富氧水对高原人体血液流变学的影响。方法①在海拔3 700m选择10名已习服半年的男性士兵,在海拔5 380m选择10名已习服2个月的男性士兵,均采用口服富氧水前(对照组)后(实验组)的自身对比运动负荷双盲实验,实验组口服5%葡萄糖注射液制成的富氧水,对照组口服5%葡萄糖注射液,均每次500mL,一日2次。运动结束检测全血粘度、全血还原粘度、血浆粘度、红细胞刚性指数、红细胞聚集指数、红细胞变形指数等血液流变学指标。②对首次进驻海拔5 200m的36名男性青年,自海拔1 400m驻地乘汽车2天到达海拔3 700m当日随机分实验组(18人,口服富氧水)和对照组(18人口服5%葡萄糖注射液),口服富氧水,方法同前。直至进入海拔5 200m某哨卡第6 d,共服9d,检测血液流变学指标。结果①海拔3 700m和5 380m负荷运动,实验组较对照组全血粘度、全血还原粘度、红细胞压积、血浆粘度、红细胞刚性指数、红细胞变形指数均降低,有显著性差异(P<0.01或0.05);红细胞高切相对指数和低切相对指数无统计学差异(P>0.05)。海拔3 700m时红细胞聚集指数降低,有显著性差异(P<0.05),海拔5 380m时无统计学差异(P>0.05)。②进驻海拔5 200m的青年,实验组较对照组全血粘度、红细胞压积、红细胞刚性指数、红细胞变形指数、血浆粘度、全血还原粘度、红细胞高切相对指数和低切相对指数均降低,有显著性差异(P<0.01或0.05);红细胞聚集指数无统计学差异(P>0.05)。结论富氧水可增加组织对氧的利用,改善微循环,预防急性高原病的发生。