作者想感谢的核心罗伯特Bloch博士，他的实验室空间和设施，并拉奥博士Gullapalli和大施慷慨捐赠，在马里兰（C - TRIM）为转化成像和磁共振研究中心（MRRC）技术支持。这项工作得到了补助金，RML（K01AR053235和1R01AR059179）国家卫生研究院和肌肉萎缩症协会（＃4278），和赠款，耆那教基金会的JAR。

1， 在体内损伤模型和等距扭矩测量。 <ol><li>这些程序可用于大鼠或小鼠7,17,18。首先，放置在动物仰卧吸入麻醉，使用精确的蒸发器（CAT＃91103，兽医装备公司，普莱森（〜4-5％的异氟醚诱导感应室，然后，通过头锥维护〜2％异氟醚） ，CA）。应用无菌眼科霜（Paralube兽医软膏，PharmaDerm，Floham公园，新泽西州），每只眼睛的角膜，以防止干燥。在实验过程中，动物笼外放置了一个烤灯保暖，从动物在任何时候都保持至少6英寸。 </li><li>预习消除头发和皮肤清洁与交替优碘和70％的酒精擦洗，以防止播种到软组织或骨皮肤上的细菌。缺乏深腱反射（没有脚捏脚撤出）确认适当的麻醉。手动放置一针是通过胫骨近端，以稳定的肢体上的钻井平台（25G或27G鼠标）。针不应该进入的腿前车厢。 </li><li>锁定到一个固定的位置，如该动物是仰卧和脚趾都面临着直线上升的针。一个特制的装置是用来固定针，从而稳定腿。 </li><li>脚下的肢体放置到一个定制加工踏板（图1）。踏板的轴步进电机（型号为T8904，NMB技术，Chatsworth的，CA）和扭矩传感器（模型QWFK - 8M，Sensotec，哥伦布，俄亥俄州）。最初应该是对齐脚，胫骨，这是正交，如图1。 </li><li>使用经皮电极（723742，剑桥，麻省，哈佛器械）或皮下电极（J05电极针针，36BTP，杰瑞电极供应，吉尔罗伊加利福尼亚），刺激颈部的腓骨，在神经附近的腓骨神经肤浅的位置。目视确认通过执行一系列的抽搐（小鼠和大鼠的1毫秒脉冲为0.1毫秒脉冲）前脚掌安全隔离背屈。一旦脚用胶布固定的踏板，在抽动的幅度在增加电压的增加证实，反对肌肉（plantarflexors）不被同时刺激。 </li><li>受伤前，在选定的时间点，在受伤后，生产dorsiflexors的能力的最大力量是记录为“等距最大扭矩”（没有改变肌肉长度的扭矩）。扭矩测量是在同一钻机，用于诱导损伤。在录音等距最大扭矩之前，脉冲幅度的调整，以优化抽搐紧张和踝关节的最佳位置，是由在不同长度的dorsiflexors给予抽搐。后获得的转矩角曲线，以确定最佳长度的dorsiflexors（休息长度，又名罗），扭矩频率图是通过逐步增加脉冲的频率在200毫秒脉冲序列。通常在90-100赫兹获得一个最大的融合强直收缩。三个独立的抽搐和强直收缩，记录和保存，作进一步的分析。 </li><li>使用商业软件（LabVIEW版本8.5，美国国家仪器公司，美国德克萨斯州奥斯汀​​）同步收缩的激活，踝关节旋转的发病和扭矩数据收集。而电脑控制的电机同时移动到跖屈踏板，从而导致延长收缩（也称为“偏心”的收缩，从而导致肌肉损伤）发生的dorsiflexor肌肉刺激。研究者所需的伤害所需的幅度取决于具体的协议。损伤的严重程度，或组织损伤，可调节的角速度，肌肉激活的时间，运动范围，并延长收缩，如变量的操纵。 </li><li>为了诱导损伤，延长收缩叠加到一个最大的等长收缩，不同范围内的议案，延长的速度，和刺激的时机需要。例如，一个最大的等长收缩是在dorsiflexors获得200毫秒后，他们在选定的速度延长至近似正常运动（900 ° /秒）。我们曾表明，激活前运动和程度的延长是重要因素，在获得伤害 14 。大多数dorsiflexors产生的扭矩是由电讯管理局局长 11，以前我们已经表明，这种模式的结果，这肌肉5,13-15受伤。电讯局长仍然刺激了整个延长。 </li><li>动物伤后，从设备中删除。胫骨针取出，清洗的腿再次返回和动物笼（温度控制的加热块放置在37 ° C）和监控，直至康复为止。这包括等待，直至动物清醒和移动。动物苦于没有观察到在手术过程中的疼痛和有步态没有明显的变化（如跛足）伤后延长收缩引起的。然而，适当的治疗抗痛随后管理（丁丙诺啡0.05 - 0.1毫克/公斤，每12小时手术后48小时）。 </li></ol> 2， 在整个肌肉紧张的现场测量。 <ol><li>动物是准备和胫骨的稳定到1.3上述第1.1节中所述。所有仪器在测试前至少30分钟打开适当的校准，以尽量减少热漂移的力传感器。 </li><li>切开皮肤前到脚踝，并切断肌腱，胫前肌（TA）。小心领带4.0爱惜康丝绸非吸收性缝合肌腱和重视薇乔缝线的称重传感器，通过所提供的的S形挂钩（重量0.1克），型号为FT03，草仪器，华威，RI）。另外，自定义钳（体重=0.5克）可以用来连接的肌腱薇乔缝合（图2）。 </li><li>称重传感器是安装一个显微（风筝机械手，世界精密仪器公司，萨拉索塔，佛罗里达州），因此，电讯局长可以调整休息长度和正确对齐（A的起源和插入之间的拉直线）。电讯管理局局长是从冷却保护，热灯和矿物油脱水。从称重传感器的信号（在每个测试之前校准）美联储通过直流放大器（型号为P122，草仪器，华威，RI）的一个A / D板，被收集和储存收购的软件（PolyVIEW 2.1版，草仪器华威，RI）。 </li><li>电讯局长的称重传感器，适用于不同的肌肉长度单抽搐（1 ms的矩形脉冲），以确定L 0。肌肉休息的长度，用标尺测量，被定义为胫骨结节和myotendinous交界处之间的距离。在这个长度，逐渐增加的脉冲幅度和脉冲频率，建立力频率的关系。强直收缩最大融合是获得约90 - 100HZ（300毫秒列车持续时间0.1 ms或1 ms脉冲组成）。使用150％的最大刺激强度激活电讯管理局局长以诱导最大收缩激活（0）。最大强直收缩，可重复执行的P 0的百分比表示，提供所需的任何时间点的疲劳指数。 </li></ol> 3， 在体内磁共振成像和/或光谱的啮齿类动物骨骼肌。 所有的MRI和MRS是在布鲁克BioSpin（比尔里卡，马萨诸塞州）7.0特斯拉核磁共振系统配备12厘米梯度插入运行Paravision 5.0软件（660吨/米，最大坡度，4570 T / M / S最大的回转速率）。 <ol><li>动物麻醉与异氟醚蒸发描述在1.1以上。磁共振兼容的小动物的监测和浇注系统（SA仪器公司）是用来监视呼吸率和体温。鼠体温度保持在36-37 ° C温水循环使用。一个特制的支架是用于定位鼠标在磁铁从膝盖到脚孔平行的两条腿的仰卧姿势。四通道接收表面线圈被放置在一个72毫米的线性1H谐振器。谐振器的线圈是调谐和匹配样品。 </li><li>磁共振成像：本地化后，下面的MR扫描表现：T1加权快速采集与松弛增强，具有以下参数（RARE）：TE = 9.52毫秒，TR = 1800，回声列车的长度= 4，在平面分辨率100 × 100微米和切片厚度为750微米。双回声PD/T2罕见：TE = 19.0/57.1毫秒，TR = 5000毫秒，回声列车的长度= 4，在平面分辨率100 × 100微米，和切片厚度为750微米。自旋回波（SE）扩散张量图像数据使用12个非共线方向：b值= 350秒/毫米-2，TE = 26毫秒，TR = 4500毫秒，在平面分辨率150X150微米和切片厚度为750微米。多层多回波（MSME）T2参数映射数据使用16工商业污水附加费= 11.4毫秒与ΔTE182.5毫秒= 11.4毫秒，TR = 10000毫秒，在平面分辨率为150X150微米，和切片厚度为750微米。 </li><li>图像处理：扩散张量的重建和跟踪技术是使用TrackVis（Martinos生物医学成像中心;马萨诸塞州总医院，波士顿，马萨诸塞）来创建平均扩散率（MD），分数各向异性（FA）的图像，以及跟踪技术的地图。 T2的映射是使用定制软件在共同商定的书面<html>劳顾会“（The MathWorks公司的Natic​​k市，MA）使用非线性最小二乘规范T2信号方程适合于每个像素的测量数据。感兴趣的测量区域内的电讯管理局局长进行评估参数值。 </li><li>上一个1 × 1 × 4毫米3在TA体素1H光谱：自动匀场。 A点分辨光谱（新闻）脉冲序列（TR / TE = 2000/18号决议MS）用于获取相同的体素从1024平均光谱。数据采集​​是每条腿34分钟。光谱数据处理使用LCModel包16。 31P光谱：一个双调谐（1H，31P）表面线圈是用来执行非本地化（使用单脉冲实验）或本地化的光谱， 利用体内光谱仪（ISIS）脉冲序列中选择图像。 </li></ol> 4。收获和储存肌肉。 助教的收获在实验结束后，称体重，管理单元在液氮中冷冻，然后储存在​​-80 ° C这可以在任何时间点后，在体内实验。肌肉收获后，立即在现场试验，因为这是一个终端程序。详细的形态学研究，动物是通过通过左心室灌注4％多聚甲醛固定。 5。代表性的成果。 图3显示了从大鼠体内仪器的有代表性的数据，在体内仪器是用来获取由dorsiflexor肌肉产生的最大扭矩;，它也可以用来诱导这些相同的肌肉损伤。由于长肌肉的紧张关系，最大的等距扭矩通常发生在踝关节的定位是在大约20 °，跖（胫骨考虑0 °定位正交脚）。获得最大等距扭矩后，脚就可以被放置到任何位置开始的伤害协议。图3表示从0 °的运动弧伤30重复协议 - 70 °。请注意在稳步下降，从等距阶段（实心箭头）和延长阶段在收缩损伤协议（开放箭头）产生扭矩。扭矩是记录NMM的单位，但绝对值取决于动物的大小和它的条件（例如，受伤的肌肉，肌肉疲劳或肌肉缺乏某种蛋白质，由于同源重组）。 图4显示了从大鼠原位仪器代表性的数据。我们的仪器在原位不涉及延长收缩，相反，它允许我们隔离开来，适当调整，并测量由一个已知长度的个别肌肉产生的最大张力。图4显示了一个老鼠在胫骨前肌的疲劳试验过程中发生的武力逐渐丧失。在这个特殊的例子，泰坦尼克号的收缩一次，第二次为5分钟。张力（力）通常记录在牛顿（或克），但扭矩一样，绝对值取决于动物的大小和条件。因为肌肉的重量后，立即获得此过程，可归的力量（所谓“特定力量”）肌肉横截面积。 图5显示了鼠标在体内成像代表性的数据，如T1加权和T2的参数映射，（A）的1 H谱（三），扩散张量成像（B） 和31个 P光谱三维跟踪技术。详情载于图例。 <img src="/files/ftp_upload/2782/2782fig1.jpg" alt="图1" /> 图1： 在体内的器具.*产生伤害，胫骨的稳定和脚连接到一个马达驱动板。脚踝dorsiflexors通过腓骨神经受到刺激，而踏板的力量足跖屈（虚线箭头）。 * 洛夫林德Deyne，J生物力学2005年，经许可使用。 <img src="/files/ftp_upload/2782/2782fig2.jpg" alt="图2" /> 图2： 在原位仪器称重传感器安装到显微因此，电讯局长可以调整休息长度的X，Y，Z方向正确并对齐。电讯局长的远端肌腱是连接称重传感器和单抽搐诱发不同的肌肉长度，以确定 L 0 。获得一个最大的强直收缩，以确定最大收缩激活（0） 。最大强直张力可重复执行，并表示百分比的P 0，想要在某个时间点提供的疲劳指数。 782/2782fig3.jpg“ALT =”图3“/&gt; 图3： 从扭矩延长收缩在大鼠体内的仪器代表跟踪录音扭矩数据 。在这个特殊的例子，肌肉刺激诱导延长的踏板900角速度70 °弧通过的议案（开放的箭头）前一个高峰的等长收缩（实心箭头）为200毫秒° /秒。 <img src="/files/ftp_upload/2782/2782fig4.jpg" alt="图4" /> 图4：从原位仪器具有代表性的数据，显示等距最大强直张力在反复刺激，在大鼠的胫前肌（TA）下降张力数据。在这个例子中，电讯局长是孤立的，调整到最佳长度（L 0），然后用200毫秒的强直收缩一次，第二次5分钟的刺激。 <img src="/files/ftp_upload/2782/2782fig5.jpg" alt="图5" /> 图5： 在活体成像答：图像显示横向（轴向）T1加权和T2从胫前肌（TA）的参数映射的部分。围绕TA点缀的红色方块显示T2在受伤增加增加（左侧）与健侧（右侧）B：扩散张量成像（DTI）的代表从三维跟踪技术：鼠标助教的 1 H频谱显示几个检测脂质共振; intramyocellular（IMCL）和extramyocellular脂质（EMCL）峰之间的分化是用这个方法取得D：31 个 P MR大鼠TA的频谱显示磷酸（PCR），无机磷（PI），而三。 5&#39; -三磷酸腺苷（ATP）的共振（α，β，γ）。

<ol>
	<li>Aldridge, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Muscle+pain+after+exercise+is+linked+with+an+inorganic+phosphate+increase+as+shown+by+31P.">Muscle pain after exercise is linked with an inorganic phosphate increase as shown by 31P.</a> NMR. Biosci. Rep. 6, 663-663 (1986).</li><li>Argov, Z., Lofberg, M., Arnold, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insights+into+muscle+diseases+gained+by+phosphorus+magnetic+resonance+spectroscopy.">Insights into muscle diseases gained by phosphorus magnetic resonance spectroscopy.</a> Muscle Nerve. 23, 1316-1316 (2000).</li><li>Brooks, S. V., Zerba, E., Faulkner, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Injury+to+muscle+fibres+after+single+stretches+of+passive+and+maximally+stimulated+muscles+in+mice.">Injury to muscle fibres after single stretches of passive and maximally stimulated muscles in mice.</a> J. Physiol. 488, 459-459 (1995).</li><li>Burkholder, 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+muscle+fiber+types+and+sizes+and+muscle+architectural+properties+in+the+mouse+hindlimb.">Relationship between muscle fiber types and sizes and muscle architectural properties in the mouse hindlimb.</a> J. Morphol. 221, 177-177 (1994).</li><li>Hakim, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dexamethasone+and+Recovery+of+Contractile+Tension+after+a+Muscle+Injury.">Dexamethasone and Recovery of Contractile Tension after a Muscle Injury.</a> Clin. Orthop. Relat Res. 439, 235-235 (2005).</li><li>Hamer, P. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evans+Blue+Dye+as+an+in+vivo+marker+of+myofibre+damage:+optimising+parameters+for+detecting+initial+myofibre+membrane+permeability.">Evans Blue Dye as an in vivo marker of myofibre damage: optimising parameters for detecting initial myofibre membrane permeability.</a> J. Anat. 200, 69-69 (2002).</li><li>Hammond, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+Autologous+Platelet-rich+Plasma+to+Treat+Muscle+Strain+Injuries.">Use of Autologous Platelet-rich Plasma to Treat Muscle Strain Injuries.</a> Am. J. Sports Med. , (2009).</li><li>Heemskerk, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+mouse+skeletal+muscle+architecture+using+three-dimensional+diffusion+tensor+imaging.">Determination of mouse skeletal muscle architecture using three-dimensional diffusion tensor imaging.</a> Magn Reson. Med. 53, 1333-1333 (2005).</li><li>Ho, K. W. <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+fiber+splitting+with+weight-lifting+exercise+in+rats.">Skeletal muscle fiber splitting with weight-lifting exercise in rats.</a> Am. J. Anat. 157, 433-433 (1980).</li><li>Huijing, P. A., Baan, G. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Myofascial+force+transmission+causes+interaction+between+adjacent+muscles+and+connective+tissue:+effects+of+blunt+dissection+and+compartmental+fasciotomy+on+length+force+characteristics+of+rat+extensor+digitorum+longus+muscle.">Myofascial force transmission causes interaction between adjacent muscles and connective tissue: effects of blunt dissection and compartmental fasciotomy on length force characteristics of rat extensor digitorum longus muscle.</a> Arch. Physiol Biochem. 109, 97-97 (2001).</li><li>Ingalls, C. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dihydropyridine+and+ryanodine+receptor+binding+after+eccentric+contractions+in+mouse+skeletal+muscle.">Dihydropyridine and ryanodine receptor binding after eccentric contractions in mouse skeletal muscle.</a> J. Appl. Physiol. 96, 1619-1619 (2004).</li><li>Lee, D., Marcinek, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Noninvasive+in+vivo+small+animal+MRI+and+MRS:+basic+experimental+procedures.">Noninvasive in vivo small animal MRI and MRS: basic experimental procedures.</a> J. Vis. Exp. , (2009).</li><li>Lovering, R. M., Deyne, P. G. D. e. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Contractile+function,+sarcolemma+integrity,+and+the+loss+of+dystrophin+after+skeletal+muscle+eccentric+contraction-induced+injury.">Contractile function, sarcolemma integrity, and the loss of dystrophin after skeletal muscle eccentric contraction-induced injury.</a> Am. J. Physiol Cell Physiol. 286, C230-C238 (2004).</li><li>Lovering, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+contribution+of+contractile+pre-activation+to+loss+of+function+after+a+single+lengthening+contraction.">The contribution of contractile pre-activation to loss of function after a single lengthening contraction.</a> J. Biomech. 38, 1501-1501 (2005).</li><li>Lovering, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recovery+of+function+in+skeletal+muscle+following+2+different+contraction-induced+injuries.">Recovery of function in skeletal muscle following 2 different contraction-induced injuries.</a> Arch. Phys. Med. Rehabil. 88, 617-617 (2007).</li><li>Provencher, S. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Automatic+quantitation+of+localized+in+vivo+1H+spectra+with+LCModel.">Automatic quantitation of localized in vivo 1H spectra with LCModel.</a> NMR Biomed. 14, 260-260 (2001).</li><li>Roche, J. A., Lovering, R. M., Bloch, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impaired+recovery+of+dysferlin-null+skeletal+muscle+after+contraction-induced+injury+in+vivo.">Impaired recovery of dysferlin-null skeletal muscle after contraction-induced injury in vivo.</a> Neuroreport. 19, 1579-1579 (2008).</li><li>Stone, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Absence+of+keratin+19+in+mice+causes+skeletal+myopathy+with+mitochondrial+and+sarcolemmal+reorganization.">Absence of keratin 19 in mice causes skeletal myopathy with mitochondrial and sarcolemmal reorganization.</a> J. Cell Sci. 120, 3999-3999 (2007).</li><li>Van Donkelaar, C. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diffusion+tensor+imaging+in+biomechanical+studies+of+skeletal+muscle+function.">Diffusion tensor imaging in biomechanical studies of skeletal muscle function.</a> J. Anat. 194, 79-79 (1999).</li><li>Vogl, 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=The+value+of+in-vivo+31-phosphorus+spectroscopy+in+the+diagnosis+of+generalized+muscular+diseases.+The+clinical+results+and+the+differential+diagnostic+aspects.">The value of in-vivo 31-phosphorus spectroscopy in the diagnosis of generalized muscular diseases. The clinical results and the differential diagnostic aspects.</a> Rofo. 162, 455-455 (1995).</li></ol>

“肌肉损伤”已定义，并在许多方面衡量。在6,9病理结果结构破坏是显而易见的，但许多用于评估肌肉损伤，包括在动物实验中使用的的生物标志物的问题，他们通常没有关联武力的损失。肌肉损伤通常被定义内用来检查它的检测的背景下，没有人发现，可以考虑在伤后的收缩变化。由于充分的收缩功能，能坚持，尽管损伤标志物的存在，可能会失去武力的最有效的措施，伤后3 ...

（所有的设备是相同的小鼠和大鼠的踏板除外） <ul><li>芽价值线柜（纽瓦克，06M4718） </li><li>多功能L / O USB - 6221M（美国国家仪器，779808-01） </li><li>步进电机控制器（纽瓦克，16M4189） </li><li>步进电机（纽瓦克，16M4198） </li><li>应变放大器（霍尼韦尔，Sensotec，DV - 05） </li><li>扭矩传感器（霍尼韦尔QWLC - 8M） </li><li>脚踏板和稳定装置（定制，正在申请专利） </li></ul>

an in vivo rodent model of contraction-induced injury and non-invasive monitoring of recovery

肌肉拉伤，医生治疗最常见的投诉之一。一个肌肉损伤通常是单独从患者的病史和体检诊断，但可以不同的临床表现大大取决于在评估肌肉损伤肌肉损伤或肌肉疾病，患者程度的损伤，病人的疼痛的耐受力等临床体征，如压痛，强度，范围的议案，最近，影像学检查，通常是有限的。生物标志物，如血清肌酸磷酸激酶水平，通常与肌肉损伤升高，但他们的水平并不总是力生产的损失相关联。这是来自动物，它提供了一个“直接的措施”损害的组织学研究结果即使如此，但没有考虑到所有的功能丧失。有些人认为，肌肉收缩力的整体健康状况的最全面的衡量。由于肌肉损伤是一个随机事件发生的各种生物力学条件下，它是很难研究。在这里，我们描述了在体内动物模型来测量扭矩，并产生一个可靠的肌肉损伤。我们还描述了我们的模型，从一个在原地隔离肌肉力测量。此外，我们描述了我们的小动物磁共振成像过程。

Watch this Scientific Journal Video about An in vivo Rodent Model of Contraction-induced Injury and Non-invasive Monitoring of Recovery at JoVE.com

An in vivo Rodent Model of Contraction-induced Injury and Non-invasive Monitoring of Recovery

一个<em&gt;在体内</em&gt;损伤的动物模型是描述。该方法采用腓骨神经的皮下位置的优势。测速，授时肌肉活化，圆弧运动，所有预先确定的，并同步使用商业软件。伤后的变化进行监测<em&gt;在体内</em&gt;，使用磁共振成像/光谱。

一个在体内收缩引起的损伤，非侵入性的监测恢复啮齿动物模型

Muscle strains are one of the most  common complaints treated by physicians. A muscle injury is typically diagnosed from the patient history and  physical ...

an-vivo-rodent-model-contraction-induced-injury-non-invasive

Research

JoVE Journal

Medicine

An in vivo Rodent Model of Contraction-induced Injury and Non-invasive Monitoring of Recovery

13.7K 次观看.  University of Maryland School of Medicine. 一个在体内损伤的动物模型是描述。该方法采用腓骨神经的皮下位置的优势。测速，授时肌肉活化，圆弧运动，所有预先确定的，并同步使用商业软件。伤后的变化进行监测在体内，使用磁共振成像/光谱。

视频: An in vivo Rodent Model of Contraction-induced Injury and Non-invasive Monitoring of Recovery

Non-invasive Optical Measurement of Cerebral Metabolism and Hemodynamics in Infants

Perinatal brain injury remains a significant cause of infant mortality and morbidity, but there is not yet an effective bedside tool that can accurately screen for brain injury, monitor injury evolution, or assess response to therapy. The energy used by neurons is derived largely from tissue oxidative metabolism, and neural hyperactivity and cell death are reflected by corresponding changes in cerebral oxygen metabolism (CMRO2). Thus, measures of CMRO2 are reflective of neuronal viability and provide critical diagnostic information, making CMRO2 an ideal target for bedside measurement of brain health.
Brain-imaging techniques such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT) yield measures of cerebral glucose and oxygen metabolism, but these techniques require the administration of radionucleotides, so they are used in only the most acute cases.
Continuous-wave near-infrared spectroscopy (CWNIRS) provides non-invasive and non-ionizing radiation measures of hemoglobin oxygen saturation (SO2) as a surrogate for cerebral oxygen consumption. However, SO2 is less than ideal as a surrogate for cerebral oxygen metabolism as it is influenced by both oxygen delivery and consumption. Furthermore, measurements of SO2 are not sensitive enough to detect brain injury hours after the insult 1,2, because oxygen consumption and delivery reach equilibrium after acute transients 3. We investigated the possibility of using more sophisticated NIRS optical methods to quantify cerebral oxygen metabolism at the bedside in healthy and brain-injured newborns. More specifically, we combined the frequency-domain NIRS (FDNIRS) measure of SO2 with the diffuse correlation spectroscopy (DCS) measure of blood flow index (CBFi) to yield an index of CMRO2 (CMRO2i) 4,5.
With the combined FDNIRS/DCS system we are able to quantify cerebral metabolism and hemodynamics. This represents an improvement over CWNIRS for detecting brain health, brain development, and response to therapy in neonates. Moreover, this method adheres to all neonatal intensive care unit (NICU) policies on infection control and institutional policies on laser safety. Future work will seek to integrate the two instruments to reduce acquisition time at the bedside and to implement real-time feedback on data quality to reduce the rate of data rejection.

We combined frequency-domain near-infrared spectroscopy measures of cerebral hemoglobin oxygenation with diffuse correlation spectroscopy measures of cerebral blood flow index to estimate an index of oxygen metabolism. We tested the utility of this measure as a bedside screening tool to evaluate the health and development of the newborn brain.

婴幼儿的脑代谢和血流动力学的非侵入式光学测量

Perinatal brain injury remains a significant cause of infant mortality  and morbidity, but there is not yet an effective bedside tool that can  accurately ...

科研

医学

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 ...

Transplantation into the Anterior Chamber of the Eye for Longitudinal, Non-invasive In vivo Imaging with Single-cell Resolution in Real-time

Intravital imaging has emerged as an indispensable tool in biological research. In the process, many imaging techniques have been developed to study different biological processes in animals non-invasively. However, a major technical limitation in existing intravital imaging modalities is the inability to combine non-invasive, longitudinal imaging with single-cell resolution capabilities. We show here how transplantation into the anterior chamber of the eye circumvents such significant limitation offering a versatile experimental platform that enables non-invasive, longitudinal imaging with cellular resolution in vivo. We demonstrate the transplantation procedure in the mouse and provide representative results using a model with clinical relevance, namely pancreatic islet transplantation. In addition to enabling direct visualization in a variety of tissues transplanted into the anterior chamber of the eye, this approach provides a platform to screen drugs by performing long-term follow up and monitoring in target tissues. Because of its versatility, tissue/cell transplantation into the anterior chamber of the eye not only benefits transplantation therapies, it extends to other in vivo applications to study physiological and pathophysiological processes such as signal transduction and cancer or autoimmune disease development.

Transplantation into the Anterior Chamber of the Eye for Longitudinal, Non-invasive In vivo Imaging with Single-cell Resolution in Real-time

A new approach combining intraocular transplantation and confocal microscopy enables longitudinal, non-invasive real-time imaging with single-cell resolution within grafted tissues in vivo. We demonstrate how to transplant pancreatic islets into the anterior chamber of the mouse eye.

纵向，非侵入性的移植到眼睛的前房<em在体内</em&gt;单细胞分辨率的实时成像

Intravital imaging has emerged as an indispensable tool in biological research.  In the process, many imaging techniques have been developed to study ...

An Alkali-burn Injury Model of Corneal Neovascularization in the Mouse

Under normal conditions, the cornea is avascular, and this transparency is essential for maintaining good visual acuity. Neovascularization (NV) of the cornea, which can be caused by trauma, keratoplasty or infectious disease, breaks down the so called &lsquo;angiogenic privilege' of the cornea and forms the basis of multiple visual pathologies that may even lead to blindness. Although there are several treatment options available, the fundamental medical need presented by corneal neovascular pathologies remains unmet. In order to develop safe, effective, and targeted therapies, a reliable model of corneal NV and pharmacological intervention is required. Here, we describe an alkali-burn injury corneal neovascularization model in the mouse. This protocol provides a method for the application of a controlled alkali-burn injury to the cornea, administration of a pharmacological compound of interest, and visualization of the result. This method could prove instrumental for studying the mechanisms and opportunities for intervention in corneal NV and other neovascular disorders.

Neovascularization (NV) of the cornea can complicate multiple visual pathologies. Utilizing a controlled, alkali-burn injury model, a quantifiable level of corneal NV can be produced for mechanistic study of corneal NV and evaluation of potential therapies for neovascular disorders.

角膜新生血管在小鼠碱烧伤模型

Under normal conditions, the cornea is avascular, and this transparency is essential for maintaining good visual acuity. Neovascularization (NV) of the ...

Murine Model for Non-invasive Imaging to Detect and Monitor Ovarian Cancer Recurrence

Epithelial ovarian cancer is the most lethal gynecologic malignancy in the United States. Although patients initially respond to the current standard of care consisting of surgical debulking and combination chemotherapy consisting of platinum and taxane compounds, almost 90% of patients recur within a few years. In these patients the development of chemoresistant disease limits the efficacy of currently available chemotherapy agents and therefore contributes to the high mortality. To discover novel therapy options that can target recurrent disease, appropriate animal models that closely mimic the clinical profile of patients with recurrent ovarian cancer are required. The challenge in monitoring intra-peritoneal (i.p.) disease limits the use of i.p. models and thus most xenografts are established subcutaneously. We have developed a sensitive optical imaging platform that allows the detection and anatomical location of i.p. tumor mass. The platform includes the use of optical reporters that extend from the visible light range to near infrared, which in combination with 2-dimensional X-ray co-registration can provide anatomical location of molecular signals. Detection is significantly improved by the use of a rotation system that drives the animal to multiple angular positions for 360 degree imaging, allowing the identification of tumors that are not visible in single orientation. This platform provides a unique model to non-invasively monitor tumor growth and evaluate the efficacy of new therapies for the prevention or treatment of recurrent ovarian cancer.

We describe a non-invasive animal imaging platform that allows the detection, quantification, and monitoring of ovarian cancer growth and recurrence. This intra-peritoneal xenograft model mimics the clinical profile of patients with ovarian cancer.

小鼠模型的非侵入性成像检测和监测卵巢癌复发

Epithelial ovarian cancer is the most lethal gynecologic malignancy in the United States. Although patients initially respond to the current standard of ...

Use of Ultra-high Field MRI in Small Rodent Models of Polycystic Kidney Disease for In Vivo Phenotyping and Drug Monitoring

Several in vivo pre-clinical studies in Polycystic Kidney Disease (PKD) utilize orthologous rodent models to identify and study the genetic and molecular mechanisms responsible for the disease, and are very convenient for rapid drug screening and testing of promising therapies. A limiting factor in these studies is often the lack of efficient non-invasive methods for sequentially analyzing the anatomical and functional changes in the kidney. Magnetic resonance imaging (MRI) is the current gold standard imaging technique to follow autosomal dominant polycystic kidney disease (ADPKD) patients, providing excellent soft tissue contrast and anatomic detail and allowing Total Kidney Volume (TKV) measurements.A major advantage of MRI in rodent models of PKD is the possibility for in vivo imaging allowing for longitudinal studies that use the same animal and therefore reducing the total number of animals required. In this manuscript, we will focus on using Ultra-high field (UHF) MRI to non-invasively acquire in vivo images of rodent models for PKD. The main goal of this work is to introduce the use of MRI as a tool for in vivo phenotypical characterization and drug monitoring in rodent models for PKD.

Use of Ultra-high Field MRI in Small Rodent Models of Polycystic Kidney Disease for In Vivo Phenotyping and Drug Monitoring

The use of ultra-high field MRI as a non-invasive way to obtain phenotypic information of rodent models for polycystic kidney disease and to monitor interventions is described. Compared with the traditional histological approach, MRI images can be acquired in vivo, allowing for longitudinal follow-up.

在多囊肾小型啮齿动物模型采用超高场磁共振成像<em&gt;在体内</em&gt;表型和药物监测

Several in vivo pre-clinical studies in Polycystic Kidney Disease (PKD) utilize orthologous rodent models to identify and study the genetic and molecular ...

Non-invasive Assessments of Subjective and Objective Recovery Characteristics Following an Exhaustive Jump Protocol

Fast recovery after strenuous exercise is important in sports and is often studied via cryotherapy applications. Cryotherapy has a significant vasoconstrictive effect, which seems to be the leading factor in its effectiveness. The resulting enhanced recovery can be measured by using both objective and subjective parameters. Two commonly measured subjective characteristics of recovery are delayed-onset muscle soreness (DOMS) and ratings of perceived exertion (RPE). Two important objective recovery characteristics are countermovement jump (CMJ) performance and peak power output (PPO). Here, we provide a detailed protocol to induce muscular exhaustion of the frontal thighs with a self-paced, 3 x 30 countermovement jump protocol (30-s rest between each set). This randomized controlled trial protocol explains how to perform local cryotherapy cuff application (+ 8 &#176;C for 20 min) and thermoneutral cuff application (+ 32 &#176;C for 20 min) on both thighs as two possible post-exercise recovery modalities. Finally, we provide a non-invasive protocol to measure the effects of these two recovery modalities on subjective (i.e., DOMS of both frontal thighs and RPE) and objective recovery (i.e., CMJ and PPO) characteristics 24, 48, and 72 h post-application. The advantage of this method is that it provides a tool for researchers or coaches to induce muscular exhaustion, without using any expensive devices; to implement local cooling strategies; and to measure both subjective and objective recovery, without using invasive methods. Limitations of this protocol are that the 30 s rest period between sets is very short, and the cardiovascular demand is very high. Future studies may find the assessment of maximum voluntary contractions to be a more sensitive assessment of muscular exhaustion compared to CMJs.

This protocol describes the procedure for non-invasive recovery assessments during a 72 h recovery period. This protocol induces muscular exhaustion of the frontal thighs using countermovement jumps and uses either local cold-cuff or thermoneutral-cuff application as a recovery modality.

根据彻底的跳跃协议进行的主观和客观恢复特征的非侵入性评估

Fast recovery after strenuous exercise is important in sports and is often studied via cryotherapy applications. Cryotherapy has a significant ...

Non-invasive Assessment of Dorsiflexor Muscle Function in Mice

Assessment of skeletal muscle contractile function is an important measurement for both clinical and research purposes. Numerous conditions can negatively affect skeletal muscle. This can result in a loss of muscle mass (atrophy) and/or loss of muscle quality (reduced force per unit of muscle mass), both of which are prevalent in chronic disease, muscle-specific disease, immobilization, and aging (sarcopenia). Skeletal muscle function in animals can be evaluated by a range of different tests. All tests have limitations related to the physiological testing environment, and the selection of a specific test often depends on the nature of the experiments. Here, we describe an in vivo, non-invasive technique involving a helpful and easy assessment of force frequency-curve (FFC) in mice that can be performed on the same animal over time. This permits monitoring of disease progression and/or efficacy&#160;of a potential therapeutic treatment.

Measurement of rodent skeletal muscle contractile function is a useful tool that can be used to track disease progression as well as efficacy of therapeutic intervention. We describe here the non-invasive, in vivo assessment of the dorsiflexor muscles that can be repeated over time in the same mouse.

小鼠肌功能的无创评价

Assessment of skeletal muscle contractile function is an important measurement for both clinical and research purposes. Numerous conditions can negatively ...

An Intact Pericardium Ischemic Rodent Model

This protocol has shown that the pericardium and its contents play an essential anti-fibrotic role in the ischemic rodent model (coronary ligation to induce myocardial injury). The majority of pre-clinical myocardial infarction models require the disruption of pericardial integrity with loss of the homeostatic cellular milieu. However, recently a methodology has been developed by us to induce myocardial infarction, which minimizes pericardial damage and retains the heart&#39;s resident immune cell population. An improved cardiac functional recovery in mice with an intact pericardial space following coronary ligation has been observed. This method provides an opportunity to study inflammatory responses in the pericardial space following myocardial infarction. Further development of the labeling techniques can be combined with this model to understand the fate and function of pericardial immune cells in regulating the inflammatory mechanisms that drive remodeling in the heart, including fibrosis.

This protocol outlines the steps for inducing myocardial infarction in mice while preserving the pericardium and its contents.

完整的心包缺血性啮齿动物模型

This protocol has shown that the pericardium and its contents play an essential anti-fibrotic role in the ischemic rodent model (coronary ligation to ...

Improved Rodent Model of Myocardial Ischemia and Reperfusion Injury

Myocardial ischemia and reperfusion injury (MIRI), induced by coronary heart disease (CHD), causes damage to the cardiomyocytes. Furthermore, evidence suggests that thrombolytic therapy or primary percutaneous coronary intervention (PPCI) does not prevent reperfusion injury. There is still no ideal animal model for MIRI. This study aims to improve the MIRI model in rats to make surgery easier and more feasible. A unique method for establishing MIRI is developed by using a soft tube during a key step of the ischemic period. To explore this method, thirty rats were randomly divided into three groups: sham group (n = 10); experimental model group (n = 10); and existing model group (n = 10). Findings of triphenyltetrazolium chloride staining, electrocardiography, and percent survival are compared to determine the accuracies and survival rates of the operations. Based on the study results, it has been concluded that the improved surgery method is associated with a higher survival rate, elevated ST-T segment, and larger infarct size, which is expected to mimic the pathology of MIRI better.

Myocardial ischemia-reperfusion model of rat heart is improved by using a self-made retractor, polyvinyl chloride tube, and a unique knotting method. Electrocardiogram, triphenyltetrazolium chloride and histological staining, and percent survival analysis results showed that the improved model group has higher success and survival rates than the already existing model group.

心肌缺血再灌注损伤的改进啮齿动物模型

Myocardial ischemia and reperfusion injury (MIRI), induced by coronary heart disease (CHD), causes damage to the cardiomyocytes. Furthermore, evidence ...