这项工作得到了德克萨斯大学阿灵顿跨学科研究项目补助金的支持。

本议定书遵循德克萨斯大学阿林顿机构审查委员会的指导方针, 符合《赫尔辛基宣言》最新版本规定的标准。因此, 在开始研究程序之前 (而且应该) 获得书面知情同意。
1. 仪器仪表
注: 以下仪器描述是基于我们实验室使用的近红外线 (近红外) 光谱仪和数据采集系统 (请参阅材料表)。因此, 指令包括这些设备的最佳功能所必需的步骤。这些步骤包括使用随附的软件和校准幻影对近红外探测器进行校准, 以及应用暗布排除周围光线。如果使用了不同的数据收集硬件和/或软件, 调查人员应参考他们自己的特定用户手册进行校准和环境光的考虑。图 1演示了下面所描述的实验设置和检测。
<ol><li>指示主体仰卧与他们的腿在一个较低的身体负压 (LBNP) 室 (图 1A), 使他们的皮带线近似地甚至与打开 LBNP 框。有关如何生成 LBNP 室的说明, 请参见引用17.
</li>
	<li>放置三心电图电极的主题: 两个在一个较低的, 锁骨上的位置和一个在主题的左侧内侧到髂嵴。这种配置提供了最好的结果, 由于有限的访问下肢, 上肢的仪器, 和手臂运动在手握演习。</li>
	<li>将无创血压监测模块放在主体手腕上。将手指血压袖口放在每个手指上, 并将它们连接到模块 (图 1B)。确保手指的血压袖口是正确的校准根据用户的手册陪同您的设备。</li>
	<li>指示该主题掌握一个手握测功机 (恒光达) 与他们的非显性手臂在一个轻微的绑架的位置。手臂应舒适地放置在床边的桌子上。恒光达的距离和角度应进行调整, 以使最佳握杆强度最小的臂移动(图 1C)。</li>
	<li>把恒光达固定在床边的桌子上。</li>
	<li>测量参与者的最大自愿收缩 (MVC)。告诉参与者, 当提示时, 他们必须尽可能用力挤压恒光达, 而只需要使用手和前臂的肌肉。指导的主题, 他们必须避免招募他们的上臂, 胸部, 肩膀, 或腹部肌肉时, 执行最大的抓地力。</li>
	<li>重复步骤1.6 三次, 至少相隔六十年代. 记录所达到的最大力 (最好为 3)。这一最大力将用于计算骨骼肌氧化能力和神经血管耦合的运动强度 (下)。</li>
	<li>在练习手的上臂周围放置一个快速充气袖口。将航空公司从快速的通货膨胀控制器连接到袖口。</li>
	<li>鉴别屈趾深肌腱。使用皮肤标记来标定可触摸肌肉的边界。</li>
	<li>确保根据您的设备附带的用户手册正确校准近红外光谱仪。清洁近红外探针将定位与酒精准备擦拭的皮肤。</li>
	<li>将近红外探针放在肌肉腹部的中心 (屈趾深肌腱) 上, 并将其安全地贴在前臂上。</li>
	<li>用深色布包裹探头和前臂, 尽量减少环境光线的干扰 (图 1C,图 1D)。</li>
	<li>当准备完成研究的功能 sympatholysis 部分时, 将主语密封到 LBNP 室。</li>
</ol>2. 骨骼肌氧化能力
注: 图2描述了用于测量骨骼肌氧化能力的实验程序的代表性数据跟踪。此实验方法以前已对体内磷夫人18和原位肌肉 respirometry19进行了验证, 并获得了广泛的接受20。
<ol><li>如上文所示 (检测) 来测量主题。</li>
	<li>通过近红外探针, 指示主体在监视脱氧 (HHb) 和 oxyhemoglobin (HbO2) 的同时, 仍要躺2分钟。 注意: 此休息期允许主题从与检测过程相关的任何移动工件中恢复, 并确保基线测量稳定。如果在2分钟后没有发生明显的波动, 则可以在稳定状态或静止基线上考虑该问题。</li>
	<li>在袖口闭塞之前, 通知你的主题, 你将充气袖口。充气上臂袖口至少 30 mmHg 以上收缩压5分钟 (即, suprasystolic)。指导该主题保持他们的手臂仍然和放松尽可能在袖口通货膨胀和后袖通货紧缩。 注: 这5分钟肱动脉袖套闭塞协议密切反映目前接受的临床标准为血管闭塞测试21,22,23,24,25。</li>
	<li>记录袖套闭塞期间的初始/基线值 (在袖扣前) 和组织饱和度的最低值 (2), 并确定这两个值之间的中点。 <img alt="Equation 1" src="/files/ftp_upload/57317/57317eq1.jpg">
</li>
	<li>允许主体从袖扣中恢复, 并返回静止基线值。一旦主题保持了至少1分钟的休息基线, 继续下一步。</li>
	<li>指导受压, 并保持一个等距的手握在50% 的 MVC。鼓励主体保持其等距收缩, 直到组织 desaturates 50%。在达到这个价值后, 告诉他们放松自己的手, 并告知他们不再需要运动或运动。</li>
	<li>在运动停止后 3-5 秒内, 管理以下快速袖扣系列 (一系列 = 1 通货膨胀 + 1 通货紧缩), 如以前建立的18: 系列 #1-6: 5 s on/5 s 关闭 系列 #7-10: 7 s on/10 s 关闭 系列 #11-14: 十年代 on/15 s 关闭 系列 #15-18: 十年代 on/20 s 关闭</li>
	<li>完成 18th通货膨胀/通货紧缩系列后, 指示该主体休息, 允许组织饱和度返回初始基线值。在这些值保持至少2分钟的一致性之后, 重复步骤2.4 和2.5。</li>
	<li>
骨骼肌氧化能力的计算
	<ol>
<li>计算2中每个单独的18个袖闭塞的变化斜率, 形成图 2C中所示的 monoexponential 恢复点。</li>
		<li>将计算数据从2.7 调整为以下 monoexponential 曲线18,19,26 y = 端Δ x e-kt 注: ' y ' 是在袖扣期间的相对肌肉耗氧率 (mV̇O2), "末端" 代表 mV̇O2在运动停止后立即;delta ("Δ") 表示 mV̇O2中的更改从 rest 到练习结束;"k" 是拟合速率常数;' t ' 是时间。头计算为 1/k。</li>
	</ol>
</li>
</ol>3. 反应性充血
注: 在图 3中描述了用于测量反应性充血的实验过程的代表性数据跟踪。
<ol><li>以主题说谎仰卧和被测量如上面描述 (仪器仪表), 指示主题说谎尽可能仍然。</li>
	<li>一旦该主题达到了一致的休息状态, 继续记录至少1分钟基线数据, 然后迅速充气一个血压袖口上手臂的 suprasystolic 压力 (30 mmHg 以上的收缩期血压)。</li>
	<li>在5分钟的标记, 迅速压缩袖口, 而记录充血的反应。</li>
	<li>继续录制至少3分钟以捕获主题的恢复。</li>
	<li>
反应性充血的计算 注: 计算的近红外光谱参数如图3所示。<ol>
<li>在动脉袖套闭塞发生之前, 将基线停用2作为平均值为2 1 全分钟。</li>
		<li>确定休息的骨骼肌代谢率为饱和率 (即,平均斜率) 在袖套闭塞 (定义为斜坡 1)27,28。</li>
		<li>计算反应性充血如下: a) 袖扣释放后的平均上坡 (即,再灌注率, 定义为斜率 2), 计算从袖口释放的时刻, 通过线性增加阶段的反弹痕迹; b) 在袖口释放后达到的最高的2值 (表示为停用2max); c) 曲线下的反应性充血区 (联合自卫队);计算从袖扣时间到 1, 2 和3分钟后袖套闭塞 (联合自卫队1分钟, 哥伦比亚自卫队2分钟, 和哥伦比亚自卫队3分钟);和 d) 充血准备金, 计算为高于基线的2的更改, 并报告为百分比 (%) 更改。此值计算为在阻塞后回弹期间达到的最高饱和度减去步骤3.5.1 中计算的平均饱和度 (见上文)。 注: 基线数据的大差异将极大地影响充血保护区的解释。</li>
	</ol>
</li>
</ol>4. 功能 Sympatholysis
注意: 描述用于测量功能 sympatholysis 的实验过程的典型数据跟踪显示在图 4中。
<ol><li>如上文所示 (检测) 来测量主题。</li>
	<li>确保密封在 LBNP 室。</li>
	<li>随着主题静止和静止, 收集3分钟的基线数据。</li>
	<li>在3分钟的标记, 打开真空。调整真空度, 使 LBNP 腔内的压力介于-20 至-30 mmHg 之间。允许真空运行2分钟, 同时监测主体的反应。</li>
	<li>在5分钟的标记, 关闭真空, 让主题休息3分钟。</li>
	<li>在8分钟的标记, 启动语音提示引导主题通过节奏的手抓练习 (20% MVC)。</li>
	<li>确认主题是保持他们的挤压整个每个抓取阶段, 并在每次重复之间完全放松。监测他们的力量输出, 并确认他们是实现 20% MVC 每一个抓地力。继续练习直到11分钟标记。</li>
	<li>在11分钟的标记, 打开真空鼓励主题继续他们的韵律运动。允许真空从 11-13 分钟运行, 然后关闭它。</li>
	<li>让主题继续执行有节奏的手握练习在20% 他们的 MVC 为另外的2分钟。运动停止后, 让主题静静地休息, 躺着不动。</li>
	<li>
计算功能 Sympatholysis
	<ol>
<li>将 oxyhemoglobin 与 LBNP 的变化正常化为总的不稳定信号 (TLS), 在5分钟袖套闭塞期间确定: <img alt="Equation 2" src="/files/ftp_upload/57317/57317eq2.jpg"> <img alt="Equation 3" src="/files/ftp_upload/57317/57317eq3.jpg">
</li>
		<li>将每个事件计算为每个事件的最终20分钟平均值。</li>
		<li>计算 oxyhemoglobin 减少的运动诱发衰减: <img alt="Equation 4" src="/files/ftp_upload/57317/57317eq4.jpg">
</li>
	</ol>
</li>
</ol>

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H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessment+of+flow-mediated+dilation+in+humans:+a+methodological+and+physiological+guideline.">Assessment of flow-mediated dilation in humans: a methodological and physiological guideline.</a> Am J Physiol Heart Circ Physiol. 300 (1), H2-H12 (2011).</li><li>Green, D. J., Jones, H., Thijssen, D., Cable, N. T., Atkinson, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flow-mediated+dilation+and+cardiovascular+event+prediction:+does+nitric+oxide+matter?.">Flow-mediated dilation and cardiovascular event prediction: does nitric oxide matter?.</a> Hypertension. 57 (3), 363-369 (2011).</li><li>Southern, W. M., Ryan, T. E., Reynolds, M. A., McCully, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reproducibility+of+near-infrared+spectroscopy+measurements+of+oxidative+function+and+postexercise+recovery+kinetics+in+the+medial+gastrocnemius+muscle.">Reproducibility of near-infrared spectroscopy measurements of oxidative function and postexercise recovery kinetics in the medial gastrocnemius muscle.</a> Appl Physiol Nutr Metab. 39 (5), 521-529 (2014).</li><li>Ryan, T. E., Erickson, M. L., Brizendine, J. T., Young, H. J., McCully, K. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Noninvasive+evaluation+of+skeletal+muscle+mitochondrial+capacity+with+near-infrared+spectroscopy:+correcting+for+blood+volume+changes.">Noninvasive evaluation of skeletal muscle mitochondrial capacity with near-infrared spectroscopy: correcting for blood volume changes.</a> J Appl Physiol. 113 (2), 175-183 (2012).</li><li>Ryan, T. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Skeletal+muscle+oxidative+capacity+in+amyotrophic+lateral+sclerosis.">Skeletal muscle oxidative capacity in amyotrophic lateral sclerosis.</a> Muscle Nerve. 50 (5), 767-774 (2014).</li><li>Mayeur, C., Campard, S., Richard, C., Teboul, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+four+different+vascular+occlusion+tests+for+assessing+reactive+hyperemia+using+near-infrared+spectroscopy.">Comparison of four different vascular occlusion tests for assessing reactive hyperemia using near-infrared spectroscopy.</a> Crit Care Med. 39 (4), 695-701 (2011).</li><li>McLay, K. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vascular+responsiveness+determined+by+near-infrared+spectroscopy+measures+of+oxygen+saturation.">Vascular responsiveness determined by near-infrared spectroscopy measures of oxygen saturation.</a> Exp Physiol. 101 (1), 34-40 (2016).</li><li>McLay, K. M., Nederveen, J. P., Pogliaghi, S., Paterson, D. H., Murias, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Repeatability+of+vascular+responsiveness+measures+derived+from+near-infrared+spectroscopy.">Repeatability of vascular responsiveness measures derived from near-infrared spectroscopy.</a> Physiol Rep. 4 (9), (2016).</li><li>Ryan, T. E., Southern, W. M., Brizendine, J. T., McCully, K. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Activity-induced+changes+in+skeletal+muscle+metabolism+measured+with+optical+spectroscopy.">Activity-induced changes in skeletal muscle metabolism measured with optical spectroscopy.</a> Med Sci Sports Exerc. 45 (12), 2346-2352 (2013).</li><li>Southern, W. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reduced+skeletal+muscle+oxidative+capacity+and+impaired+training+adaptations+in+heart+failure.">Reduced skeletal muscle oxidative capacity and impaired training adaptations in heart failure.</a> Physiol Rep. 3 (4), (2015).</li><li>Ryan, T. E., Brizendine, J. T., McCully, K. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comparison+of+exercise+type+and+intensity+on+the+noninvasive+assessment+of+skeletal+muscle+mitochondrial+function+using+near-infrared+spectroscopy.">A comparison of exercise type and intensity on the noninvasive assessment of skeletal muscle mitochondrial function using near-infrared spectroscopy.</a> J Appl Physiol. 114 (2), 230-237 (2013).</li><li>Adami, A., Cao, R., Porszasz, J., Casaburi, R., Rossiter, H. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reproducibility+of+NIRS+assessment+of+muscle+oxidative+capacity+in+smokers+with+and+without+COPD.">Reproducibility of NIRS assessment of muscle oxidative capacity in smokers with and without COPD.</a> Respir Physiol Neurobiol. 235, 18-26 (2017).</li><li>Lacroix, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reproducibility+of+near-infrared+spectroscopy+parameters+measured+during+brachial+artery+occlusion+and+reactive+hyperemia+in+healthy+men.">Reproducibility of near-infrared spectroscopy parameters measured during brachial artery occlusion and reactive hyperemia in healthy men.</a> J Biomed Opt. 17 (7), 077010 (2012).</li><li>Bopp, C. M., Townsend, D. K., Warren, S., Barstow, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Relationship+between+brachial+artery+blood+flow+and+total+[hemoglobin+myoglobin]+during+post-occlusive+reactive+hyperemia.">Relationship between brachial artery blood flow and total [hemoglobin+myoglobin] during post-occlusive reactive hyperemia.</a> Microvasc Res. 91, 37-43 (2014).</li><li>Willingham, T. B., Southern, W. M., McCully, K. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measuring+reactive+hyperemia+in+the+lower+limb+using+near-infrared+spectroscopy.">Measuring reactive hyperemia in the lower limb using near-infrared spectroscopy.</a> J Biomed Opt. 21 (9), 091302 (2016).</li><li>Kragelj, R., Jarm, T., Erjavec, T., Presern-Strukelj, M., Miklavcic, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Parameters+of+postocclusive+reactive+hyperemia+measured+by+near+infrared+spectroscopy+in+patients+with+peripheral+vascular+disease+and+in+healthy+volunteers.">Parameters of postocclusive reactive hyperemia measured by near infrared spectroscopy in patients with peripheral vascular disease and in healthy volunteers.</a> Ann Biomed Eng. 29 (4), 311-320 (2001).</li><li>Gurley, K., Shang, Y., Yu, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Noninvasive+optical+quantification+of+absolute+blood+flow,+blood+oxygenation,+and+oxygen+consumption+rate+in+exercising+skeletal+muscle.">Noninvasive optical quantification of absolute blood flow, blood oxygenation, and oxygen consumption rate in exercising skeletal muscle.</a> J Biomed Opt. 17 (7), 075010 (2012).</li></ol>

作者声明他们没有竞争的财政利益。

本文所述方法可在单个诊所或实验室访问中进行无创、无反应性充血、神经血管耦合和骨骼肌氧化能力的临床评价。
关键考虑事项
虽然近红外光谱是相对健壮和易于使用, 收集这些数据需要仔细放置的 optodes 直接在肌肉腹部, 固定到位, 以避免运动工件, 并覆盖在昏暗的房间里的黑色乙烯基板, 以避免外部光对近红外的干扰。此外, 获得?...

充血对短暂的组织缺血的反应已成为一种关键的非侵入性测量 (微) 血管功能。在导管动脉闭塞期间, 下游动脉扩张, 以抵消缺血性的侮辱。在阻断后, 血管阻力的减少导致充血, 其大小取决于一个人的能力来扩张下游微管。虽然反应性充血是心血管事件的一个强有力的独立预测因子1,2 , 因此一个临床重要的终点, 它的功能意义, 锻炼耐受性和生活质量是不太清楚。
事实上, 动态运动是一种主要的心血管压力, 需要高度协调的神经血管反应, 以便将氧气输送与新陈代谢需求相匹配。例如, 骨骼肌血流可以增加近100倍, 在单独的肌肉收缩3, 这将压倒心脏的抽水能力, 如果这样的血流动力学反应被推断为全身运动。因此, 为了避免严重的低血压, 交感神经 (即,收缩) 神经活动增加, 重新分配心脏输出远离非活动和内脏组织和对主动骨骼肌4。交感神经流出也被定向到运动骨骼肌5;然而, 局部代谢信号减弱收缩反应, 以确保足够的组织氧气输送6,7,8,9,10, 11. 总的来说, 这个过程被称为功能 sympatholysis12, 对运动过程中骨骼肌血流的正常调节是必不可少的。由于骨骼肌血流是有氧能力的关键决定因素--生命质量和心血管疾病发病率和死亡率的独立预测因子13-了解骨骼肌血流和组织氧的控制运动期间分娩具有重要的临床意义。
然而, 氧气的传递只是菲克方程的一半, 氧气的利用满足了等式的另一半。在氧利用的主要决定中, 线粒体氧化磷酸化对于在静止和运动期间为细胞过程提供足够的能量起着至关重要的作用。事实上, 肌肉氧化能力的损害可以限制功能能力和生活质量14,15,16。各种措施通常用于提供肌肉氧化能力指标, 包括侵入性肌肉活检和昂贵和耗时的磁共振光谱学 (夫人) 技术。
在这里, 我们提出了一种新的, 非侵入性的方法, 使用近红外光谱分析, 以评估这三个主要临床终点 (活性充血, sympatholysis 和肌肉氧化能力) 在一个单一的诊所或实验室访问。该方法的主要优点是三倍: 首先, 该技术易于携带, 成本相对较低, 易于执行。目前的多普勒超声检测反应性充血的方法是高度依赖于操作者-需要广泛的技能和培训-并需要复杂, 高成本, 数据采集硬件和后处理软件。此外, 这可能被引入到临床和/或大型临床试验, 为床边监测或测试的疗效。其次, 根据该方法, 该技术特别注重骨骼肌微血管, 提高了技术的整体特异性。其他方法使用多普勒超声聚焦在上游导管容器和推断变化下游, 这可能会减弱信号。第三, 这种技术是完全无侵入性的。骨骼肌氧化能力传统上是用侵袭性和痛苦的肌肉活检来评估的, 功能 sympatholysis 可以用动脉内注射 sympathomimetics 和 sympatholytics 来评估。这种方法完全避免了这些要求。

<table border="0" cellpadding="0" cellspacing="0" width="836">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:328px;">Dual-channel OxiplexTS Near-infrared spectroscopy machine</td>
			<td style="width:223px;">Iss Medical</td>
			<td align="right" style="width:119px;">101</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:328px;">NIRS muscle sensor</td>
			<td style="width:223px;">Iss Medical</td>
			<td align="right" style="width:119px;">201.2</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:328px;">E20 Rapid cuff inflation system</td>
			<td style="width:223px;">Hokanson</td>
			<td style="width:119px;">E20</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:328px;">AG101 Air Source</td>
			<td style="width:223px;">Hokanson</td>
			<td style="width:119px;">AG101</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:328px;">Smedley Handgrip dynometer (recording)</td>
			<td style="width:223px;">Stolting</td>
			<td align="right" style="width:119px;">56380</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:328px;">Powerlab 16/35, 16 Channel Recorder</td>
			<td style="width:223px;">ADInstruments</td>
			<td style="width:119px;">PL3516</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:328px;">Human NIBP Set</td>
			<td style="width:223px;">ADInstruments</td>
			<td style="width:119px;">ML282-SM</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:328px;">Bio Amp</td>
			<td style="width:223px;">ADInstruments</td>
			<td style="width:119px;">FE132</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:328px;">Quad Bridge Amp</td>
			<td style="width:223px;">ADInstruments</td>
			<td style="width:119px;">FE224</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:328px;">Connex Spot Monitor</td>
			<td style="width:223px;">Welch Allyn</td>
			<td style="width:119px;">71WX-B</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:328px;">Origin(Pro) graphing software</td>
			<td style="width:223px;">OrignPro</td>
			<td style="width:119px;">Pro</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:328px;">Lower body negative pressure chamber</td>
			<td style="width:223px;">Physiology Research Instruments</td>
			<td style="width:119px;">standard unit</td>
			<td></td>
		</tr>
	</tbody>
</table>

skeletal muscle neurovascular coupling, oxidative capacity, and microvascular function with 'one stop shop' near-infrared spectroscopy

运动是一种主要的血流动力学压力, 需要高度协调的神经血管反应, 以便将氧气输送与新陈代谢需求相匹配。反应性充血 (在短时间内组织缺血) 是心血管事件的独立预测因子, 为血管的健康和舒张能力提供了重要的洞察力。骨骼肌氧化能力在健康和疾病中同样重要, 因为它决定了 myocellular 过程的能量供应。在这里, 我们描述了一个简单的, 非侵入性的方法, 使用近红外光谱评估这些主要临床终点 (反应性充血, 神经血管耦合, 肌肉氧化能力) 在一个单一的诊所或实验室访问。不同于多普勒超声, 磁共振图像/光谱学, 或侵入导管的流量测量或肌肉活检, 我们的方法是较少的操作者依赖, 低成本, 完全没有侵入。我们实验室的代表性数据连同先前发表的文献中的摘要数据, 说明了每个端点的效用。一旦掌握了这种技术, 应用到临床人群将提供重要的机械洞察力的运动不耐受和心血管功能障碍。

骨骼肌氧化能力
图 2说明了在近红外光谱衍生骨骼肌氧化能力评估期间有代表性的参与者反应。面板 a 显示了5分钟的动脉袖套闭塞协议, 手柄运动, 和间歇性动脉闭塞在运动恢复期间的组织饱和度剖面。小组 B 说明在恢复期间歇性动脉闭塞期间, 预期的组织饱和/再饱和度剖面。饱和的?...

Watch this Scientific Journal Video about Skeletal Muscle Neurovascular Coupling, Oxidative Capacity, and Microvascular Function with 'One Stop Shop' Near-infrared Spectroscopy at JoVE.com

Skeletal Muscle Neurovascular Coupling, Oxidative Capacity, and Microvascular Function with 'One Stop Shop' Near-infrared Spectroscopy

"一站式" 近红外光谱对骨骼肌神经血管的耦合、氧化能力及微血管功能的作用

在这里, 我们描述了一个简单的, 非侵入性的方法, 使用近红外光谱评估反应性充血, 神经血管耦合和骨骼肌氧化能力的单一诊所或实验室访问。

Exercise represents a major hemodynamic stress that demands a highly coordinated neurovascular response in order to match oxygen delivery to metabolic ...

skeletal-muscle-neurovascular-coupling-oxidative-capacity

Research

JoVE Journal

Medicine

12.4K 次观看.  University of Texas at Arlington. 在这里, 我们描述了一个简单的, 非侵入性的方法, 使用近红外光谱评估反应性充血, 神经血管耦合和骨骼肌氧化能力的单一诊所或实验室访问。

视频: Skeletal Muscle Neurovascular Coupling, Oxidative Capacity, and Microvascular Function with 'One Stop Shop' Near-infrared Spectroscopy

Myo-mechanical Analysis of Isolated Skeletal Muscle

To assess the in vivo effects of therapeutic interventions for the treatment of muscle disease 1,2,3, quantitative methods are needed that measure force generation and fatigability in treated muscle. We describe a detailed approach to evaluating myo-mechanical properties in freshly explanted hindlimb muscle from the mouse. We describe the atraumatic harvest of mouse extensor digitorum longus muscle, mounting the muscle in a muscle strip myograph (Model 820MS; Danish Myo Technology), and the measurement of maximal twitch and tetanic tension, contraction time, and half-relaxation time, using a square pulse stimulator (Model S48; Grass Technologies). Using these measurements, we demonstrate the calculation of specific twitch and tetanic tension normalized to muscle cross-sectional area, the twitch-to-tetanic tension ratio, the force-frequency relationship curve and the low frequency fatigue curve 4. This analysis provides a method for quantitative comparison between therapeutic interventions in mouse models of muscle disease 1,2,3,5, as well as comparison of the effects of genetic modification on muscle function 6,7,8,9.

To assess the in vivo effects of therapeutic interventions for muscle disease, methods are needed to quantitate force generation and fatigability in treated muscle. We detail an approach to evaluating myo-mechanical properties in explanted mouse hindlimb muscle. This analysis provides a robust approach to quantitating the effects of genetic modification on muscle function, as well as comparison of therapies in mouse models of muscle disease.

离体骨骼肌肌的力学分析

To assess the in vivo effects of therapeutic interventions for the treatment of muscle disease 1,2,3, quantitative methods are needed that measure force ...

科研

医学

In Vivo Canine Muscle Function Assay

We describe a minimally-invasive and reproducible method to measure canine pelvic limb muscle strength and muscle response to repeated eccentric 
contractions. The pelvic limb of an anesthetized dog is immobilized in a stereotactic frame to align the tibia at a right angle to the femur. Adhesive wrap affixes the 
paw to a pedal mounted on the shaft of a servomotor to measure torque. Percutaneous nerve stimulation activates pelvic limb muscles of the paw to either push (extend) or 
pull (flex) against the pedal to generate isometric torque. Percutaneous tibial nerve stimulation activates tibiotarsal extensor muscles. Repeated eccentric (lengthening) 
contractions are induced in the tibiotarsal flexor muscles by percutaneous peroneal nerve stimulation. The eccentric protocol consists of an initial isometric contraction 
followed by a forced stretch imposed by the servomotor. The rotation effectively lengthens the muscle while it contracts, e.g., an eccentric contraction. During 
stimulation flexor muscles are subjected to an 800 msec isometric and 200 msec eccentric contraction. This procedure is repeated every 5 sec. To avoid fatigue, 4 min rest 
follows every 10 contractions with a total of 30 contractions performed.

In Vivo Canine Muscle Function Assay

We describe a minimally-invasive and painless method to measure canine hindlimb muscle strength and muscle response to repeated eccentric contractions.

在犬体内的肌肉功能测定

We describe a minimally-invasive and reproducible method to measure canine pelvic limb muscle strength and muscle response to repeated eccentric 
...

Skeletal Muscle Gender Dimorphism from Proteomics

Gross contraction in skeletal muscle is primarily determined by a relatively small number of contractile proteins, however this tissue is also remarkably adaptable to environmental factors1 such as hypertrophy by resistance exercise and atrophy by disuse. It thereby exhibits remodeling and adaptations to stressors (heat, ischemia, heavy metals, etc.)2,3. Damage can occur to muscle by a muscle exerting force while lengthening, the so-called eccentric contraction4. The contractile proteins can be damaged in such exertions and need to be repaired, degraded and/or resynthesized; these functions are not part of the contractile proteins, but of other much less abundant proteins in the cell. To determine what subset of proteins is involved in the amelioration of this type of damage, a global proteome must be established prior to exercise5 and then followed subsequent to the exercise to determine the differential protein expression and thereby highlight candidate proteins in the adaptations to damage and its repair. Furthermore, most studies of skeletal muscle have been conducted on the male of the species and hence may not be representative of female muscle. 
In this article we present a method for extracting proteins reproducibly from male and female muscles, and separating them by two-dimensional gel electrophoresis followed by high resolution digital imaging6. This provides a protocol for spots (and subsequently identified proteins) that show a statistically significant (p &lt; 0.05) two-fold increase or decrease, appear or disappear from the control state. These are then excised, digested with trypsin and separated by high-pressure liquid chromatography coupled to a mass spectrometer (LC/MS) for protein identification (LC/MS/MS)5. This methodology (Figure 1) can be used on many tissues with little to no modification (liver, brain, heart etc.).

A straight-forward set of methods to isolate and determine the identity of the most abundant proteins expressed in skeletal muscle. About 800 spots are discerned on a two-dimensional gel from 10 mg muscle; this allows for the determination of gender-specific protein expression. These methods will give equivalent results in most tissues.

骨骼肌蛋白质组学性别异形

Gross contraction in skeletal muscle is primarily determined by a relatively small number of contractile proteins, however this tissue is also remarkably ...

Non-invasive Assessment of Microvascular and Endothelial Function

The authors have utilized capillaroscopy and forearm blood flow techniques to investigate the role of microvascular dysfunction in pathogenesis of cardiovascular disease. Capillaroscopy is a non-invasive, relatively inexpensive methodology for directly visualizing the microcirculation. Percent capillary recruitment is assessed by dividing the increase in capillary density induced by postocclusive reactive hyperemia (postocclusive reactive hyperemia capillary density minus baseline capillary density), by the maximal capillary density (observed during passive venous occlusion). Percent perfused capillaries represents the proportion of all capillaries present that are perfused (functionally active), and is calculated by dividing postocclusive reactive hyperemia capillary density by the maximal capillary density. Both percent capillary recruitment and percent perfused capillaries reflect the number of functional capillaries. The forearm blood flow (FBF) technique provides accepted non-invasive measures of endothelial function: The ratio FBFmax/FBFbase is computed as an estimate of vasodilation, by dividing the mean of the four FBFmax values by the mean of the four FBFbase values. Forearm vascular resistance at maximal vasodilation (FVRmax) is calculated as the mean arterial pressure (MAP) divided by FBFmax. Both the capillaroscopy and forearm techniques are readily acceptable to patients and can be learned quickly.
The microvascular and endothelial function measures obtained using the methodologies described in this paper may have future utility in clinical patient cardiovascular risk-reduction strategies. As we have published reports demonstrating that microvascular and endothelial dysfunction are found in initial stages of hypertension including prehypertension, microvascular and endothelial function measures may eventually aid in early identification, risk-stratification and prevention of end-stage vascular pathology, with its potentially fatal consequences.

Capillaroscopy is a non-invasive, relatively inexpensive methodology for directly visualizing the microcirculation. The forearm blood flow technique provides accepted non-invasive measures of endothelial function.

非侵入性的评估微血管和内皮功能

The authors have utilized capillaroscopy and forearm blood flow techniques to investigate the role of microvascular dysfunction in pathogenesis of ...

Quantitative Magnetic Resonance Imaging of Skeletal Muscle Disease

Quantitative magnetic resonance imaging (qMRI) describes the development and use of MRI to quantify physical, chemical, and/or biological properties of living systems. Neuromuscular diseases often exhibit a temporally varying, spatially heterogeneous, and multi-faceted pathology. The goal of this protocol is to characterize this pathology using qMRI methods. The MRI acquisition protocol begins with localizer images (used to locate the position of the body and tissue of interest within the MRI system), quality control measurements of relevant magnetic field distributions, and structural imaging for general anatomical characterization. The qMRI portion of the protocol includes measurements of the longitudinal and transverse relaxation time constants (T1 and T2, respectively). Also acquired are diffusion-tensor MRI data, in which water diffusivity is measured and used to infer pathological processes such as edema. Quantitative magnetization transfer imaging is used to characterize the relative tissue content of macromolecular and free water protons. Lastly, fat-water MRI methods are used to characterize fibro-adipose tissue replacement of muscle. In addition to describing the data acquisition and analysis procedures, this paper also discusses the potential problems associated with these methods, the analysis and interpretation of the data, MRI safety, and strategies for artifact reduction and protocol optimization.

Neuromuscular diseases often exhibit a temporally varying, spatially heterogeneous, and multi-faceted pathology. The goal of this protocol is to characterize this pathology using non-invasive magnetic resonance imaging methods.

骨骼肌疾病的定量磁共振成像

Quantitative magnetic resonance imaging (qMRI) describes the development and use of MRI to quantify physical, chemical, and/or biological properties of ...

Combined Near-infrared Fluorescent Imaging and Micro-computed Tomography for Directly Visualizing Cerebral Thromboemboli

Direct thrombus imaging visualizes the root cause of thromboembolic infarction. Being able to image thrombus directly allows far better investigation of stroke than relying on indirect measurements, and will be a potent and robust vascular research tool. We use an optical imaging approach that labels thrombi with a molecular imaging thrombus marker&#160;&#8212; a Cy5.5 near-infrared fluorescent (NIRF) probe that is covalently linked to the fibrin strands of the thrombus by the fibrin-crosslinking enzymatic action of activated coagulation factor XIIIa during the process of clot maturation. A micro-computed tomography (microCT)-based approach uses thrombus-seeking gold nanoparticles (AuNPs) functionalized to target the major component of the clot: fibrin. This paper describes a detailed protocol for the combined in vivo microCT and ex vivo NIRF imaging of thromboemboli in a mouse model of embolic stroke. We show that in vivo microCT and fibrin-targeted glycol-chitosan AuNPs (fib-GC-AuNPs) can be used for visualizing both in situ thrombi and cerebral embolic thrombi. We also describe the use of in vivo microCT-based direct thrombus imaging to serially monitor the therapeutic effects of tissue plasminogen activator-mediated thrombolysis. After the last imaging session, we demonstrate by ex vivo NIRF imaging the extent and the distribution of residual thromboemboli in the brain. Finally, we describe quantitative image analyses of microCT and NIRF imaging data. The combined technique of direct thrombus imaging allows two independent methods of thrombus visualization to be compared: the area of thrombus-related fluorescent signal on ex vivo NIRF imaging vs. the volume of hyperdense microCT thrombi in vivo.

This protocol describes the application of combined near-infrared fluorescent (NIRF) imaging and micro-computed tomography (microCT) for visualizing cerebral thromboemboli. This technique allows the quantification of thrombus burden and evolution. The NIRF imaging technique visualizes fluorescently labeled thrombus in excised brain, while the microCT technique visualizes thrombus inside living animals using gold-nanoparticles.

结合近红外荧光成像和微计算机断层扫描直接可视化脑血栓

Direct thrombus imaging visualizes the root cause of thromboembolic infarction. Being able to image thrombus directly allows far better investigation of ...

Phosphorus-31 Magnetic Resonance Spectroscopy: A Tool for Measuring In Vivo Mitochondrial Oxidative Phosphorylation Capacity in Human Skeletal Muscle

Skeletal muscle mitochondrial oxidative phosphorylation (OXPHOS) capacity, which is critically important in health and disease, can be measured in vivo and noninvasively in humans via phosphorus-31 magnetic resonance spectroscopy (31PMRS). However, the approach has not been widely adopted in translational and clinical research, with variations in methodology and limited guidance from the literature. Increased optimization, standardization, and dissemination of methods for in vivo 31PMRS would facilitate the development of targeted therapies to improve OXPHOS capacity and could ultimately favorably impact cardiovascular health. 31PMRS produces a noninvasive, in vivo measure of OXPHOS capacity in human skeletal muscle, as opposed to alternative measures obtained from explanted and potentially altered mitochondria via muscle biopsy. It relies upon only modest additional instrumentation beyond what is already in place on magnetic resonance scanners available for clinical and translational research at most institutions. In this work, we outline a method to measure in vivo skeletal muscle OXPHOS. The technique is demonstrated using a 1.5 Tesla whole-body MR scanner equipped with the suitable hardware and software for 31PMRS, and we explain a simple and robust protocol for in-magnet resistive exercise to rapidly fatigue the quadriceps muscle. Reproducibility and feasibility are demonstrated in volunteers as well as subjects over a wide range of functional capacities.

Phosphorus-31 Magnetic Resonance Spectroscopy: A Tool for Measuring In Vivo Mitochondrial Oxidative Phosphorylation Capacity in Human Skeletal Muscle

This work demonstrates the feasibility of an in vivo phosphorus-31 magnetic resonance spectroscopy (31PMRS) technique to quantify mitochondrial oxidative phosphorylation (OXPHOS) capacity in human skeletal muscle.

磷31磁共振波谱分析:一种测量工具<em&gt;在体内</em&gt;线粒体氧化磷酸化能力人骨骼肌

Skeletal muscle mitochondrial oxidative phosphorylation (OXPHOS) capacity, which is critically important in health and disease, can be measured in vivo ...

Assessment of Human Adipose Tissue Microvascular Function Using Videomicroscopy

While obesity is closely linked to the development of metabolic and cardiovascular disease, little is known about mechanisms that govern these processes. It is hypothesized that pro-atherogenic mediators released from fat tissues particularly in association with central/visceral adiposity may promote pathogenic vascular changes locally and systemically, and the notion that cardiovascular disease may be the consequence of adipose tissue dysfunction continues to evolve. Here, we describe a unique method of videomicroscopy that involves analysis of vasodilator and vasoconstrictor responses of intact small human arterioles removed from the adipose depot of living human subjects. Videomicroscopy is used to examine functional properties of isolated microvessels in response to pharmacological or physiological stimuli using a pressured system that mimics in vivo conditions. The technique is a useful approach to gain understanding of the pathophysiology and molecular mechanisms that contribute to vascular dysfunction locally within the adipose tissue milieu. Moreover, abnormalities in the adipose tissue microvasculature have also been linked with systemic diseases. We applied this technique to examine depot-specific vascular responses in obese subjects. We assessed endothelium-dependent vasodilation to both increased flow and acetylcholine in adipose arterioles (50 - 350 &#181;m internal diameter, 2 - 3 mm in length) isolated from two different adipose depots during bariatric surgery from the same individual. We demonstrated that arterioles from visceral fat exhibit impaired endothelium-dependent vasodilation compared to vessels isolated from the subcutaneous depot. The findings suggest that the visceral microenvironment is associated with vascular endothelial dysfunction which may be relevant to clinical observation linking increased visceral adiposity to systemic disease mechanisms. The videomicroscopy technique can be used to examine vascular phenotypes from different fat depots as well as compare findings across individuals with different degrees of obesity and metabolic dysfunction. The method can also be used to examine vascular responses longitudinally in response to clinical interventions.

Videomicroscopy systems are used to examine functional properties of isolated adipose tissue arterioles in response to physiological and pharmacological stimuli. This technique can be used to examine microvascular phenotypes in different adipose tissue domains in obese humans.

应用 Videomicroscopy 评价人脂肪组织微血管功能

While obesity is closely linked to the development of metabolic and cardiovascular disease, little is known about mechanisms that govern these processes. ...

A New Best Practice for Validating Tail Vein Injections in Rat with Near-infrared-Labeled Agents

Intravenous (IV) administration of agents into the tail vein of rats can be both difficult and inconsistent. Optimizing tail vein injections is a key part of many experimental procedures where reagents need to be introduced directly into the bloodstream. Unwittingly, the injection can be subcutaneous, possibly altering the scientific outcomes. Utilizing a nanoemulsion-based biological probe with an incorporated near-infrared fluorescent (NIRF) dye, this method offers the capability of imaging a successful tail vein injection in vivo. With the use of a NIRF imager, images are taken before and after the injection of the agent. An acceptable IV injection is then qualitatively or quantitatively determined based on the intensity of the NIRF signal at the site of injection.

Here we present a method to validate tail vein injections in rats by utilizing near-infrared fluorescence imaging data from dyes incorporated into agents or biological probes. The tail is imaged before and after the injection, the fluorescent signal is quantified, and an assessment of the injection quality is made.

近红外标记剂对大鼠尾静脉注射的新的最佳验证

Intravenous (IV) administration of agents into the tail vein of rats can be both difficult and inconsistent. Optimizing tail vein injections is a key part ...

How to Administer Near-Infrared Spectroscopy in Critically ill Neonates, Infants, and Children

Near infrared spectroscopy (NIRS) calculates regional tissue oxygenation (rSO2) using the different absorption spectra of oxygenated and deoxygenated hemoglobin molecules. A probe placed on the skin emits light that is absorbed, scattered, and reflected by the underlying tissue. Detectors in the probe sense the amount of reflected light: this reflects the organ-specific ratio of oxygen supply and consumption - independent of pulsatile flow. Modern devices enable the simultaneous monitoring at different body sites. A rise or dip in the rSO2 curve visualizes changes in oxygen supply or demand before vital signs indicate them. The evolution of rSO2 values in relation to the starting point is more important for interpretation than are absolute values.
A routine clinical application of NIRS is the surveillance of somatic and cerebral oxygenation during and after cardiac surgery. It is also administered in preterm infants at risk for necrotizing enterocolitis, newborns with hypoxic ischemic encephalopathy and a potential risk of impaired tissue oxygenation. In the future, NIRS could be increasingly used in multimodal neuromonitoring, or applied to monitor patients with other conditions (e.g., after resuscitation or traumatic brain injury).

This protocol is designed to assist clinicians to measure regional tissue oxygenation at different body sites in infants and children. It can be used in situations where tissue oxygenation is potentially compromised, particularly during cardiopulmonary bypass, when using non-pulsatile cardiac-assist devices, and in critically ill neonates, infants and children.

如何管理危重新生儿、婴儿和儿童近红外光谱

Near infrared spectroscopy (NIRS) calculates regional tissue oxygenation (rSO2) using the different absorption spectra of oxygenated and deoxygenated ...