睡眠剥夺对力竭运动大鼠胸腺谷胱甘肽、丙二醛、超氧化物歧化酶的影响

目的:观察不同睡眠剥夺时间后力竭运动对大鼠胸腺谷胱甘肽、丙二醛含量和超氧化物歧化酶活性的变化,探讨睡眠剥夺对大鼠抗氧化能力的影响。方法:实验于2006-04/05在湖南师范大学体育学院运动生物化学实验室完成。实验分组:选择10周龄健康雄性SD大鼠30只,按随机数字表法分为5组,每组6只:睡眠非运动组,睡眠 力竭运动组和睡眠剥夺24,48,72h 力竭运动组。实验方法:①采用轻柔刺激法制备大鼠睡眠剥夺模型。②睡眠非运动组和睡眠 力竭运动组不进行睡眠剥夺。③睡眠 力竭运动组和睡眠剥夺各组大鼠运动方案:跑台坡度为10°,速度为19.3m/min(相当于76%VO2max),所有大鼠运动至力竭(运动末期,大鼠先后滞留跑道后1/3处达3次以上,各种刺激驱赶均无效,停跑后体征表现为呼吸急促,神情倦怠,腹卧位,对刺激反应迟钝,捕捉时,逃避反应较运动前减弱)。实验评估:①大鼠一般状态。②力竭时间。③大鼠力竭后麻醉处死,测定胸腺谷胱甘肽、丙二醛含量和超氧化物歧化酶活性。结果:纳入大鼠30只,均进入结果分析。①大鼠一般状态:睡眠 力竭运动组大鼠表现为形态正常,活泼好动,皮毛光亮,眼睛有神;睡眠剥夺48,h 力竭运动组大鼠均出现神态倦怠,眼神黯淡,四肢亦有不同程度的红肿;睡眠剥夺24h 力竭运动组大72鼠介于以上两者之间。②睡眠 力竭运动组和睡眠剥夺24,7248,h组大鼠的力竭时间分别为(232.36±37.67),(269.19±38.61),(162.42±35.70),(141.07±28.56)。③谷胱甘肽含量、超氧化物歧化酶活性:睡眠 力竭运动组谷胱甘肽含量和超氧min化物歧化酶活性均低于睡眠非运动组[分别为(25.54±0.79),(27.09±1.31)mg/g;(±0.21),(±0.10)mkat/g],差异有显4.594.88著性意义(P<0.05);睡眠剥夺24h 力竭运动组谷胱甘肽含量和超氧化物歧化酶活性均高于睡眠非运动组[分别为(28.60±0.96),(27.09±1.31)mg/g;(±0.10),(±0.10)5.234.88mkat/g],差异有显著性意义(P<0.05),睡眠剥夺48,h 力竭运动组P72均低于睡眠非运动组[分别为(23.74±1.19),(22.43±0.52),(27.09±1.31)mg/g;(±0.14),(±0.18),(±0.10)mkat/g],4.523.354.88差异均有非常显著性意义(P<0.01);睡眠剥夺各组与睡眠 力竭运动组间谷胱甘肽含量和超氧化物歧化酶活性差异均有非常P显著性意义(P<0.01);睡眠剥夺各组间比较差异有显著性意义(P<0.05)。④丙二醛浓度:睡眠 力竭运动组丙二醛浓度高于P睡眠非运动组[分别为(±0.27),(±0.24)μmol/L],差异有非常显著性意义(P<0.01);睡眠剥夺各组与睡眠非运动组之间6.565.35P差异均有非常显著性意义(P<0.01);睡眠剥夺24,48,72h 力竭运动组丙二醛含量均高于睡眠 力竭运动组[分别为(±0.12),(±P7.398.850.72),(10.89±0.82),(±0.27)μmol/L],差异有显著性意义(P<0.05;P<0.01);睡眠剥夺各组间比较,睡眠剥夺48h与睡眠剥夺24h差6.56异无显著性意义(P>0.05),睡眠剥夺72h与睡眠剥夺24h、睡眠剥夺72h与睡眠剥夺48h间比较差异有非常显著性意义(P<0.01)。结论:①睡眠剥夺24h可引起大鼠胸腺氧化应激,使氧自由基能力有所增强。②睡眠剥夺48,72h力竭运动后氧自由基能力降低。     

Differences in Transverse Abdominis Activation with Stable and Unstable Bridging Exercises in Individuals with Low Back Pain

Background

The transversus abdominis (TrA) is a spine stabilizer frequently targeted during rehabilitation exercises for individuals with low back pain (LBP). Performance of exercises on unstable surfaces is thought to increase muscle activation, however no research has investigated differences in TrA activation when stable or unstable surfaces are used.

Objective

The purpose of this study was to investigate whether TrA activation in individuals with LBP is greater when performing bridging exercises on an unstable surface versus a stable surface.

Methods

Fifty one adults (mean ± SD, age 23.1 ± 6.0 years, height 173.60 ± 10.5 cm, mass 74.7 ± 14.5 kg) with stabilization classification of LBP were randomly assigned to either exercise progression utilizing a sling bridge device or a traditional bridging exercise progression, each with 4 levels of increasing difficulty. TrA activation ratio (TrA contracted thickness/TrA resting thickness) was measured during each exercise using ultrasound imaging. The dependent variable was the TrA activation ratio.

Results

The first 3 levels of the sling-based and traditional bridging exercise progression were not significantly different. There was a significant increase in the TrA activation ratio in the sling-based exercise group when bridging was performed with abduction of the hip (1.48 ± .38) compared to the traditional bridge with abduction of the hip (1.22 ± .38; p<.05).

Conclusion

Both types of exercise result in activation of the TrA, however, the sling based exercise when combined with dynamic movement resulted in a significantly higher activation of the local stabilizers of the spine compared to traditional bridging exercise. This may have implications for rehabilitation of individuals with LBP.     

Expression of a Common LQT1 Mutation in Five Apparently Unrelated Families in a Regional Inherited Arrhythmia Clinic

Expression of a Common LQT1 Mutation. Background: The Inherited Arrhythmia Clinic at the University of Western Ontario services a catchment area of 1.5 million people and follows families with inherited arrhythmia syndromes. Methods: Patients referred for evaluation of long‐QT Syndrome (LQTS) are evaluated with resting and standing ECGs, and treadmill exercise testing. Patients with findings consistent with LQTS are offered comprehensive genetic testing with screening of all first‐degree relatives of genotype‐positive patients. Results: Among 31 probands with disease‐causing LQTS mutations, 5 probands from apparently unrelated families of Irish descent were found to have an identical disease causing transmembrane mutation in KCNQ1 (Leu266Pro). Systematic screening of 33 first‐degree relatives of genotype‐positive individuals detected 15 unaffected and 18 asymptomatic affected family members. Symptoms in 6 patients occurred later in life than reported LQT1 populations (61 ± 18 years, range 44–89). In this cohort, several family members presented with cardiac arrest during acute myocardial ischemia (n = 2), sudden death, unexplained drowning, and torsade de pointes during exercise testing. There was no identifiable common relative for this cohort after pedigree construction of the previous 4–7 generations. Affected patients had mild QT prolongation at rest with dramatic QT prolongation with exercise. Conclusions: Genetic testing in this LQTS population suggests a common KCNQ1 Leu266Pro founder effect, with the descendants clustering in our geographical region even though no common relative has been identified. The observations highlight the utility of genotypic and phenotypic correlation and a specialized clinic. (J Cardiovasc Electrophysiol, Vol. 21, pp. 296–300, March 2010)     

<Emphasis Type="Italic">Streptobacillus moniliformis</Emphasis> septic arthritis: a clinical entity distinct from rat-bite fever?

Background  

Streptobacillus moniliformis is a zoonotic agent associated with rodent contacts. Although it is more commonly reported to cause rat-bite fever with reactive arthritides, it can also lead to pyogenic infection of the joints.     

4-甲氧羰基芬太尼的4-N-丙酰基结构类似物的合成与镇痛活性

本文报道了4-甲氧羰基芬太尼4-N-丙酰基结构改变衍生物的合成及其镇痛活性。试验结果表明,该类衍生物均具有典型吗啡样作用的性质。多数化合物具有很强的镇痛活性。其中1379,1385和1387的镇痛活性强于先导物4-甲氧羰基芬太尼。     

6-取代苯基-3(2H)哒嗪酮的合成、抗惊活性及其构效关系的研究

本文报道了14个6-取代苯基-4,5-二氢-3(2H)哒嗪酮和15个6-取代苯基-3(2H)哒嚎酮的合成及其抗电惊活性。其ED₅₀值表明,以2′,4′-二氯苯基-3(2H)哒嗪酮的抗惊作用为最强。构效分析表明,苯环上的取代基对化合物的抗惊活性有明显影响,吸电子取代基和疏水性参数值较大的取代基有利于提高化合物的抗惊活性。     

复方螺旋藻片对高血脂症小鼠血脂的影响

目的：观察复方螺旋藻片（FST）对高脂血症小鼠血脂的影响。方法：用FST1.5mg/kg,3g/kg分别灌胃给予高脂血症小鼠,连续14d后,眼眶取血测血脂。结果：与高脂血症模型对照组相比,FST高、低剂量能显著降低血清TC、TG和LDL－C水平,明显升高血清HDL－C水平与HDL－C／TC比值。同时FST还能升高血清apoAI并降低apoB(但FST 1.5g/kg对apoB无明显影响）。结论：FST能明显降低高脂血症小鼠血脂水平,并对载脂蛋白有一定的调节作用。     

Exposure injury: Examining heat- and cold-related illnesses and injuries

Heat- and cold-related illnesses represent a broad spectrum of preventable common conditions affecting diverse populations every year. Clinicians treating patients near areas of outdoor recreation and nursing homes or who potentially see critical pediatric, indigent, or intoxicated patients can benefit from a better understanding of exposure injuries. Heat-related illnesses include the continuum of heat rash, heat cramps, heat exhaustion, and the potentially deadly heat stroke. Cold-related illnesses encompass a broad array of conditions ranging from soft tissue injuries like pernio, trench foot, and frostnip to the more severe effects of frostbite and hypothermia. The majority of patients with severe environmental exposure would usually present to an emergency or urgent care center; however, milder acute cases and more subtle chronic presentations would generally first be seen by a primary care physician. With any temperature-related illness, the family physician's role should most importantly include identification of at-risk populations and promotion of proper preventative strategies allowing early symptom recognition and rapid treatment.     

Visual cognition associated with knee proprioception,time to stability,and sensory integration neural activity after ACL reconstruction

Visual cognitive ability has previously been associated with anterior cruciate ligament injury and injury risk biomechanics in healthy athletes. Neuroimaging reports have identified increased neural activity in regions corresponding to visual-spatial processing, sensory integration, and visual cognition in individuals after anterior cruciate ligament reconstruction (ACLR), indicating potential neural compensatory strategies for motor control. However, it remains unclear whether there is a relationship between visual cognition, neural activity, and metrics of neuromuscular ability after ACLR. The purpose of this study was to (1) evaluate the relationship between visual cognitive function and measurements of neuromuscular control (proprioception and time to stability [TTS]), isokinetic strength, and subjective function, and (2) examine the neural correlates of visual cognition between ACLR (n = 16; time since surgery 41.4 ± 33.0 months) and demographically similar controls (n = 15). Visual cognition was assessed by the ImPACT visual motor and visual memory subscales. Outcome variables of proprioception to target knee angle 20°, landing TTS, strength, and subjective function were compared between groups, and visual cognition was correlated within groups to determine the relationship between visual cognition and outcome variables controlled for time from surgery (ACLR group). The control group had better IKDC scores and strength. Visual memory and visual motor ability were negatively associated with proprioception error (r = ?0.63) and TTS (r = ?0.61), respectively, in the ACLR group but not controls. Visual cognition was associated with increased neural activity in the precuneus and posterior cingulate cortex in the ACLR group but not control participants. These data suggest the neural strategy in which ACLR participants maintain proprioception and stability varies, and may depend on visual cognition and sensory integration neural activity.