雷帕霉素靶蛋白(mammaliantarget of rapamycin,mTOR)是丝氨酸/苏氨酸蛋白激酶,能感受细胞中的氨基酸、生长因子、能量及环境压力等信号,通过下游效应蛋白调控翻译起始因子,调控蛋白质的合成。作者对近年来mTOR研究的新进展及其在骨骼...雷帕霉素靶蛋白(mammaliantarget of rapamycin,mTOR)是丝氨酸/苏氨酸蛋白激酶,能感受细胞中的氨基酸、生长因子、能量及环境压力等信号,通过下游效应蛋白调控翻译起始因子,调控蛋白质的合成。作者对近年来mTOR研究的新进展及其在骨骼肌蛋白质合成中的作用进行了综述。展开更多
Background Phosphorous magnetic resonance spectroscopy （31p-MRS） has been successfully applied to study intracellular membrane compounds and high-energy phosphate metabolism.This study aimed to evaluate the capabili...Background Phosphorous magnetic resonance spectroscopy （31p-MRS） has been successfully applied to study intracellular membrane compounds and high-energy phosphate metabolism.This study aimed to evaluate the capability of dynamic 31p-MRS for assessing energy metabolism and mitochondrial function in skeletal muscle from type 2 diabetic patients.Methods Dynamic 31p-MRS was performed on 22 patients with type 2 diabetes and 26 healthy volunteers.Spectra were acquired from quadriceps muscle while subjects were in a state of rest,at exercise and during recovery.The peak areas of inorganic phosphate （Pi）,phosphocreatine （PCr）,and adenosine triphosphate （ATP） were measured.The concentration of adenosine diphosphate （ADP） and the intracellular pH value were calculated from the biochemistry reaction equilibrium.The time constant and recovery rates of Pi,PCr,and ADP were analyzed using exponential curve fitting.Results As compared to healthy controls,type 2 diabetes patients had significantly lower skeletal muscle concentrations of Pi,PCr and β-ATP,and higher levels of ADP and Pi/PCr.During exercise,diabetics experienced a significant Pi peak increase and PCr peak decrease,and once the exercise was completed both Pi and PCr peaks returned to resting levels.Quantitatively,the mean recovery rates of Pi and PCr in diabetes patients were （10.74±1.26） mmol/s and （4.74±2.36） mmol/s,respectively,which was significantly higher than in controls.Conclusions Non-invasive quantitative 31P-MRS is able to detect energy metabolism inefficiency and mitochondrial function impairment in skeletal muscle of type 2 diabetics.展开更多
Background: Children are affected by disorders that have an impact on the respiratory muscles. Inspiratory muscle function can be assessed by means of the noninvasive tension–time index of the inspiratory muscles(TTI...Background: Children are affected by disorders that have an impact on the respiratory muscles. Inspiratory muscle function can be assessed by means of the noninvasive tension–time index of the inspiratory muscles(TTImus). Our objectives were to identify the determinants of TTImus in healthy children and to report normal values of TTImus in this population.Methods: We measured weight, height, upper arm muscle area(UAMA), and TTImusin 96 children aged 6–18 years. The level and frequency of aerobic activity was assessed by questionnaire.Results: TTImuswas significantly lower in male subjects(0.095 ± 0.038, mean ± SD) compared with female subjects(0.126 ± 0.056)(p = 0.002).TTImus was significantly lower in regularly exercising(0.093 ± 0.040) compared with nonexercising subjects(0.130 ± 0.053)(p < 0.001). TTImus was significantly negatively related to age(r =-0.239, p = 0.019), weight(r =-0.214, p = 0.037), height(r =-0.355, p < 0.001), and UAMA(r =-0.222, p = 0.030). Multivariate logistic regression analysis revealed that height and aerobic exercise were significantly related to TTImus independently of age, weight, and UAMA. The predictive regression equation for TTImus in male subjects was TTImus = 0.228-0.001 × height(cm), and in female subjects it was TTImus = 0.320-0.001 × height(cm).Conclusion: Gender, age, anthropometry, skeletal muscularity, and aerobic exercise are significantly associated with indices of inspiratory muscle function in children. Normal values of TTImus in healthy children are reported.展开更多
目的:评价老年住院患者呼吸肌力量与肢体肌功能的关系。方法:纳入70名60岁以上的老年住院患者(43名男性和27名女性)。肢体肌的评估包括肢体肌量、肌力及肌功能。肌量评估使用生物阻抗分析法(bioelectrical impedance analysis,BIA),测...目的:评价老年住院患者呼吸肌力量与肢体肌功能的关系。方法:纳入70名60岁以上的老年住院患者(43名男性和27名女性)。肢体肌的评估包括肢体肌量、肌力及肌功能。肌量评估使用生物阻抗分析法(bioelectrical impedance analysis,BIA),测量后计算四肢肌容积指数(appendicular skeletal musc lemassindex, ASMI)。肢体肌力及肢体功能评估通过握力(handgrips trength,HGS)、平常步速(usualgaitspeed,UGS)、5次起坐实验(fivetimessittostandtest,FTSST)进行评估。呼吸肌力量通过肺功能测试中的最大吸气压(maximalinspiratorypressure,MIP)、最大呼气压(maximal expiratory pressure,MEP)及呼气峰流速(peak expiratory flow,PEF)评估。使用Sp ea r m a n相关性分析和多元线性回归分析研究呼吸肌和肢体肌功能之间的关系。结果:MIP与ASMI、UGS呈正相关(r=0.346、0.332,均P<0.01),与血清白蛋白、血红蛋白呈正相关(r=0.264、0.2 7 3,均P <0.0 5),与年龄呈负相关(r=-0.2 5 2, P <0.0 5)。M E P与A S M I、 H G S、 U G S均呈正相关(r=0.357、0.324、0.330,均P<0.01)。PEF与ASMI、HGS、UGS均呈正相关(r=0.334、0.334、0.346,均P<0.01)。在调整年龄后,以MIP、 MEP、PEF为因变量的多元线性回归分析中,均为其独立影响因素(分别β=0.319、0.314、0.318,均P<0.01);另外,ASMI为MIP的独立预测因素(β=0.275,P<0.05)。结论:呼吸肌力量与四肢骨骼肌质量相关,其中吸气肌力量与四肢骨骼肌质量显著相关;呼吸肌力量与以步速为评估方式的肢体肌功能呈显著相关。展开更多
目的本研究旨在探讨直肠癌新辅助放化疗(NACRT)对测量体内肌肉线粒体功能和身体体质的影响。方法我们前瞻性地研究了35例完成标准化NACRT的直肠癌患者,受试者均来自于2018年3月至2019年3月期间入住我院患者。所有患者在NACRT前后均接受...目的本研究旨在探讨直肠癌新辅助放化疗(NACRT)对测量体内肌肉线粒体功能和身体体质的影响。方法我们前瞻性地研究了35例完成标准化NACRT的直肠癌患者,受试者均来自于2018年3月至2019年3月期间入住我院患者。所有患者在NACRT前后均接受了心肺功能运动试验(CPET)和磷磁共振光谱分析四头肌运动后恢复情况。数据分析和报告中的患者身份及其临床过程完全保密。主要变量是两个体质测试包括评估无氧阈值时的摄氧量和运动峰值时摄氧量(m L·kg^-1·min^-1),以及一种在体内测量肌肉线粒体容量的方法—运动后磷酸肌酸恢复速率常数(min^-1)。结果患者平均年龄为67±5岁,3个主要变量在NACRT后呈显著负相关(95%CI):评估无氧阈值时摄氧量为-2.5 m L·kg^-1·min^-1(-3.7,-1.1),P=0.005;运动峰值时摄氧量为-3.9 m L·kg^-1·min^-1(-6.7,-1.1),P=0.015;和运动后磷酸肌酸(PCr)恢复速率常数为-0.4 min^-1(-0.5,-0.2),P=0.011。结论身体体质和体内肌肉线粒体功能的明显降低可能是由于肌肉线粒体的多因素机制引起,并可能影响NACRT后的体质恶化,这说明术前针对性的干预措施能提高身体体质。展开更多
文摘Background Phosphorous magnetic resonance spectroscopy （31p-MRS） has been successfully applied to study intracellular membrane compounds and high-energy phosphate metabolism.This study aimed to evaluate the capability of dynamic 31p-MRS for assessing energy metabolism and mitochondrial function in skeletal muscle from type 2 diabetic patients.Methods Dynamic 31p-MRS was performed on 22 patients with type 2 diabetes and 26 healthy volunteers.Spectra were acquired from quadriceps muscle while subjects were in a state of rest,at exercise and during recovery.The peak areas of inorganic phosphate （Pi）,phosphocreatine （PCr）,and adenosine triphosphate （ATP） were measured.The concentration of adenosine diphosphate （ADP） and the intracellular pH value were calculated from the biochemistry reaction equilibrium.The time constant and recovery rates of Pi,PCr,and ADP were analyzed using exponential curve fitting.Results As compared to healthy controls,type 2 diabetes patients had significantly lower skeletal muscle concentrations of Pi,PCr and β-ATP,and higher levels of ADP and Pi/PCr.During exercise,diabetics experienced a significant Pi peak increase and PCr peak decrease,and once the exercise was completed both Pi and PCr peaks returned to resting levels.Quantitatively,the mean recovery rates of Pi and PCr in diabetes patients were （10.74±1.26） mmol/s and （4.74±2.36） mmol/s,respectively,which was significantly higher than in controls.Conclusions Non-invasive quantitative 31P-MRS is able to detect energy metabolism inefficiency and mitochondrial function impairment in skeletal muscle of type 2 diabetics.
文摘Background: Children are affected by disorders that have an impact on the respiratory muscles. Inspiratory muscle function can be assessed by means of the noninvasive tension–time index of the inspiratory muscles(TTImus). Our objectives were to identify the determinants of TTImus in healthy children and to report normal values of TTImus in this population.Methods: We measured weight, height, upper arm muscle area(UAMA), and TTImusin 96 children aged 6–18 years. The level and frequency of aerobic activity was assessed by questionnaire.Results: TTImuswas significantly lower in male subjects(0.095 ± 0.038, mean ± SD) compared with female subjects(0.126 ± 0.056)(p = 0.002).TTImus was significantly lower in regularly exercising(0.093 ± 0.040) compared with nonexercising subjects(0.130 ± 0.053)(p < 0.001). TTImus was significantly negatively related to age(r =-0.239, p = 0.019), weight(r =-0.214, p = 0.037), height(r =-0.355, p < 0.001), and UAMA(r =-0.222, p = 0.030). Multivariate logistic regression analysis revealed that height and aerobic exercise were significantly related to TTImus independently of age, weight, and UAMA. The predictive regression equation for TTImus in male subjects was TTImus = 0.228-0.001 × height(cm), and in female subjects it was TTImus = 0.320-0.001 × height(cm).Conclusion: Gender, age, anthropometry, skeletal muscularity, and aerobic exercise are significantly associated with indices of inspiratory muscle function in children. Normal values of TTImus in healthy children are reported.
文摘目的:评价老年住院患者呼吸肌力量与肢体肌功能的关系。方法:纳入70名60岁以上的老年住院患者(43名男性和27名女性)。肢体肌的评估包括肢体肌量、肌力及肌功能。肌量评估使用生物阻抗分析法(bioelectrical impedance analysis,BIA),测量后计算四肢肌容积指数(appendicular skeletal musc lemassindex, ASMI)。肢体肌力及肢体功能评估通过握力(handgrips trength,HGS)、平常步速(usualgaitspeed,UGS)、5次起坐实验(fivetimessittostandtest,FTSST)进行评估。呼吸肌力量通过肺功能测试中的最大吸气压(maximalinspiratorypressure,MIP)、最大呼气压(maximal expiratory pressure,MEP)及呼气峰流速(peak expiratory flow,PEF)评估。使用Sp ea r m a n相关性分析和多元线性回归分析研究呼吸肌和肢体肌功能之间的关系。结果:MIP与ASMI、UGS呈正相关(r=0.346、0.332,均P<0.01),与血清白蛋白、血红蛋白呈正相关(r=0.264、0.2 7 3,均P <0.0 5),与年龄呈负相关(r=-0.2 5 2, P <0.0 5)。M E P与A S M I、 H G S、 U G S均呈正相关(r=0.357、0.324、0.330,均P<0.01)。PEF与ASMI、HGS、UGS均呈正相关(r=0.334、0.334、0.346,均P<0.01)。在调整年龄后,以MIP、 MEP、PEF为因变量的多元线性回归分析中,均为其独立影响因素(分别β=0.319、0.314、0.318,均P<0.01);另外,ASMI为MIP的独立预测因素(β=0.275,P<0.05)。结论:呼吸肌力量与四肢骨骼肌质量相关,其中吸气肌力量与四肢骨骼肌质量显著相关;呼吸肌力量与以步速为评估方式的肢体肌功能呈显著相关。
文摘目的本研究旨在探讨直肠癌新辅助放化疗(NACRT)对测量体内肌肉线粒体功能和身体体质的影响。方法我们前瞻性地研究了35例完成标准化NACRT的直肠癌患者,受试者均来自于2018年3月至2019年3月期间入住我院患者。所有患者在NACRT前后均接受了心肺功能运动试验(CPET)和磷磁共振光谱分析四头肌运动后恢复情况。数据分析和报告中的患者身份及其临床过程完全保密。主要变量是两个体质测试包括评估无氧阈值时的摄氧量和运动峰值时摄氧量(m L·kg^-1·min^-1),以及一种在体内测量肌肉线粒体容量的方法—运动后磷酸肌酸恢复速率常数(min^-1)。结果患者平均年龄为67±5岁,3个主要变量在NACRT后呈显著负相关(95%CI):评估无氧阈值时摄氧量为-2.5 m L·kg^-1·min^-1(-3.7,-1.1),P=0.005;运动峰值时摄氧量为-3.9 m L·kg^-1·min^-1(-6.7,-1.1),P=0.015;和运动后磷酸肌酸(PCr)恢复速率常数为-0.4 min^-1(-0.5,-0.2),P=0.011。结论身体体质和体内肌肉线粒体功能的明显降低可能是由于肌肉线粒体的多因素机制引起,并可能影响NACRT后的体质恶化,这说明术前针对性的干预措施能提高身体体质。
