代表性数据的产生是由美国国立卫生研究院资助R01HL084178，5R01MH068767-08，并从布朗的MRI研究设施和罗得岛基金会的赠款支持。弗吉尼亚州南车研发补助1 IK2 CX000724-01A2支持的协议的发展和进一步的工作。我们感谢我们所有的参与者。

合资格参与人签署书面知情同意参加研究项目。研究符合执行与人类福利机构，国家和国际准则。 1，参加筛查和诊断访谈<ol><li>知情同意后，进行诊断访谈，以核实创伤后应激障碍的诊断和病情严重程度。注意:这些措施包括DSM-IV-TR的结构化临床访谈（SCID）24和用药PTSD评分表的临床医生（CAPS）25，以及在Folstein简易精神状态检查（MMSE）26来评估认知状态。 </li><li>请参与者填写相关的压力和情绪的自我报告量表。 注:其中包括生命应激清单-修订（LSC-R）27，儿童期创伤问卷（CTQ）28，知觉压力量表（PSS）29和抑郁症状的快速清查S（QIDS-SR）30。 </li><li>计划的合资格参与者的核磁共振，参与者计划扫描会话之前到达约1小时，审查所需的扫描组件，如MRI的安全性和研究程序。 </li><li>获得尿，妊娠（适当的时候），和毒理学试验前扫描。 </li></ol> 2，培训参与者执行的N-back任务<ol><li>开始先用0回一封信警觉试运行。 <ol><li>指导学员通过两个按钮的响应框和"否"的所有其他辅音字母来表示"是"辅音一个目标（"H"或"H"）。 </li><li>显示参与者9个辅音为每500毫秒，与2500 ms的刺激间的时间，总共27秒，并要求他们作出反应，定向以上。注:目标辅音将显示每个0回块内4次。 </li></ol></li><li>接下来，已参加练习2-BACK的测试。 <ol><li>指导学员制作上的两个按钮的响应盒一个"是"或"否"响应，在每个辅音提出，以表明它是否是相同的或不同的辅音提出了两个以前在一个系列。 </li><li>显示参与者的一系列15个辅音，而每500毫秒，与2500毫秒的刺激间隔，总共45秒。注:一个目标刺激如图5倍。 </li></ol></li><li>火车参与者进行第n-back任务扫描仪之外，直到他们的表现达到&gt; 75％的2型回组件是否正确。注意:上面的参数可以通过刺激呈现软件自动化（见表材料/设备）。 </li></ol> 3，MRI收购<ol><li>有参与者转变成核磁共振兼容的衣服，并给他们带来了3特斯拉MRI扫描仪的房间内。让他们戴上耳塞对听力保护，然后在西港岛线轮床上躺下升，最终将它们移到MRI机器的中间。 <ol><li>周围放置他们的头部靠垫，尽量减少头部运动。与第n回工作记忆任务中的核磁共振兼容的响应盒提供它们，挤压球停止扫描在紧急情况下，并放置一个脉搏血氧仪对他们的手指生理监测和记录。 </li><li>将32通道头线圈及以上参与者的头部演示画面，并把它们放入扫描仪的中间。 </li></ol></li><li>确保参与者能心情舒畅地看到屏幕，然后开始在MRI扫描会话。开始采集高分辨率（1毫米3）解剖脑部扫描。在回波时间（TE）输入电脑灯控制台上的高分辨率MRI参数= 2.98毫秒，重复时间（TR）= 1,900毫秒，视场（FOV）= 256 平方毫米和矩阵大小64 2 1毫米的薄片。通过按下扫描"运行"按钮，开始采集MRI检查NER控制台。 </li><li>扫描仪控制台TR = 2500毫秒，TE = 28毫秒，FOV = 192 平方毫米，而矩阵大小64 2 3㎜轴片上设置的FMRI的BOLD图像采集参数。 </li><li>接下来，获取对工作记忆的FMRI图像，使用n回测试（见第2节）使用以下参数: <ol><li>提出了一个30秒的基线固定交叉，给病人之前，使用每个刺激呈现软件0回块。注意:这将提供一个基准作比较;其他0 - 2回块中的数据分析。 </li><li>项目的说明，病人持续3秒前，各自为0或2-back任务使用的刺激呈现软件。 </li><li>总体而言，包括三名0后卫和2回部分以及两个基准块，两种成像奔跑，在反平衡的顺序排列。 </li></ol></li><li>按MRI扫描仪控制台上的"运行"开始。 </li><li>正回完成后，确保参与者是舒适，并准备继续前进。指示他们，剩下的块是下一个，并告诉他们不要睡着。使用刺激呈现软件，在屏幕上显示一个固定的交叉。 </li><li>获得静息状态下的图像在接下来的4分钟，用作为用于收购正影像相同的FMRI设置（见3.3），按"运行"MRI扫描仪控制台上。 </li><li>重复步骤3.4。和3.5。在此之前每个新节，询问参与者，如果他们都非常舒适，如果他们能够继续。如果他们能够继续的协议。如果不是，暂停核磁共振成像扫描仪，并根据需要令人舒适的调整。 </li><li>接下来，告诉扫描仪可能会在接下来的顺序摇晃参与者，并指示他们闭上眼睛，因为最好的，他们可以在扫描仪中放松身心。然后按电脑灯控制台上的"运行"按钮获取DTI序列。 </li><li>在扫描仪浓度设定DTI图像采集参数鞋底双自旋回波平面扩散加权图像（DWI），并在64个非共线的方向（β= 1,000），1 DWI对每个梯度方向和10个非加权（B = 0）归一化的图像，TR施加扩散梯度= 10,060毫秒，TE = 103毫秒，FOV =226毫米，128×2矩阵，层厚为1.8毫米，局部回声和插值。 </li><li>从扫描仪中取出的参与者，并询问如何了会议去了。回答他们的任何问题，并感谢他们的参与。拥有核磁共振成像扫描仪电脑写的DVD参与者的影像和生理记录为后续的数据分析。 </li></ol> 4，数据分析<ol><li>数据预处理<ol><li>使用fMRI处理软件，重建原始数据转换成3D +时间的数据集，串连并注册的第一个系列的第五卷，尽量减少运动伪影并产生运动校正参数。应用带通滤波（0.009-0.08赫兹）来隔离DMN的频域，并减少低频漂移和高频噪声的影响。注:每个像素冇变量应包括平均心室和白质的时间序列以及头部运动的6参数​​估计;这些估算应包括贬低和导数值。滋扰变量的预测时间当然应该从完整的体素的时间序列被移除，以产生"残余"的时间序列数据，以用于以后的相关分析31。 </li><li>大规模的数据正常化内运行强度，平滑数据高达4毫米的半峰全宽（FWHM）高斯核。从数据集32大于1.5 mm排量御史图像。不执行全局信号回归（GSR），因为GSR可以在休息状态数据33,34影响的相关性。 </li></ol></li><li>静息状态下连接分析<ol><li>使用种子区域连通性分析，以评估一个先验定义区域之间的关系来评价功能连接11。注:包括种子是DMN的，分别主要前部和后部的节点时，内侧前额叶和PCC。这些位置的功能坐标一般优于图谱定义的位置35。 </li><li>从这些种子中提取的平均BOLD时间序列，并进行全脑相关性分析。变换相关性的R值到Z分数为36以后的假设检验。 <ol><li>由体素的基础上比较Z值的体素组之间，以评估创伤后应激障碍和控制为主要观察指标之间的功能连接显著差异。阈值这些结果在在P双尾显着性&lt;0.05，使用家庭明智的（ 即集群）纠错。注意:使用蒙特卡罗模拟来估计假阳性簇的概率产生集群修正。使用统计算法毫秒计算群集校正作为视场，分辨率，平整度的函数，并且在个体体素级37的信号强度。 </li></ol></li><li>为了评估临床症状和影像学检查结果之间的关系，进行后续的分析，包括评定量表分数和DMN区域的连通性平均Z值之间的相关性。包括相关分析该帐户相关的人口统计信息，如抑郁症的严重程度，脑外伤，以及教育和其他相关变量。 </li></ol></li><li>工作记忆分析<ol><li>使用FMRI处理软件进行预处理的数据，并基于体素的GLM量化特定任务的活动中各个数据集11,31的各体素的脑。注:在GLM独立变量是休息和0的时间过程 - 和2 - 回任务（包括建模为伽玛函数血流动力学转换）和协变量（线性漂移和观察二维运动），与BOLD信号随时间作为因变量。 </li><li>一般导致在规定的DMN地区GLM测试砝码。注:从个体层面的数据集，这些均正返回响应作为在随后的组级的统计分析大脑活动的基本措施。 </li><li>协方差分析的使用，研究创伤后应激障碍和非PTSD组之间组水平的差异，并估计任务难度（活动期间0 即比较- 与 2回任务）的影响在每个DMN区域;还包括任何相关的统计控制措施分析静息状态下分析了4.2过程中根据需要。 </li></ol></li><li>结构连接使用DTI <ol><li>预处理<ol><li>使用DTI处理软件，共同注册的非扩散（ 即 ，B = 0）的图像校正运动伪影，并作为后续弥散加权图像的归一化图像使用。使用12参数仿射变换注册弥散加权图像来解释运动和涡流文物。 </li><li>确保每个扩散方向的梯度向量旋转占到模型拟合之前转换。使用约束拟合程序38非线性扩散加权信号衰减计算每个体素二阶扩散张量。 </li><li>使用弥散加权图像来计算特征值，特征向量和扩散的各向异性分数地图。 </li></ol></li><li>使用跟踪技术软件来量化的的扣带束的完整性。利用标准图谱进行种子区域选择，如那些由森等人的 39和卡塔尼和德的Schotten 40。通过中线排除区域筛选产生的跟踪技术，除去纤维半球之间穿越。计算平均FA，跟踪，轴向和径向扩散，通过其扣带回通过所有体素。&lt;/ LI&gt; <li>使用混合模型方差分析对每个扩散的措施，以半球作为被试内变量，比较PTSD和非PTSD参与者之间的组间差异，在统计学上控制了其他因素，如严重抑郁症，物质滥用，轻度脑外伤，教育和人口采用协方差分析的变量。 </li></ol></li></ol>

The authors have no conflicts of interest to disclose relevant to the content of this manuscript. Both Dr. Philip and Ms. Carpenter are US Government Employees.

成功实施了神经成像协议的两个最关键的步骤是准确地捕获静止状态和工作记忆的影响。 从概念上讲，收购静止状态的图像很简单。由于没有要执行的任务，实验者经常形容大脑活动在这时代的"休息"。然而，由于这一领域是相对较新的相比，神经影像学检查1的其他领域，有一个如何准确定义"其余部分没有明确的共识"在扫描器。大多数协议，包括这一个，要求学员?...

神经影像学代表以前所未有的潜力的工具来检查诊断的有效性，生病，预测和神经精神病学中治疗反应的严重程度。广泛的互补性神经影像学技术现在可用于表征关键脑神经系统的结构和功能，并在精神病人群的神经影像学表型的鉴定提供帮助。这些系统中，默认模式网络（DMN）已经获得了极大的关注，在认知和临床神经科学文献在过去的十年。 该DMN是一种所谓的"静息状态网络"，包括内侧前额叶皮层（MPFC）为主要节点前，后扣带回皮质/楔前叶（PCC）为原则后路节点，随着劣质外侧顶叶皮层和内侧颞区。这个网络的，他们主要特点是，它在休息期间，WHI表现其活性最高发生通道，而主体是清醒和警觉，但不参与具体的任务;这种静息状态下的活动是创造脑功能1的"默认模式"。静息状态下的活动在DMN也高度同步，这被描述为静息状态功能连接。该DMN的其他主要特点是，它表明在增加外部认知要求期间的活动减弱， 功能神经影像学期间被观察到的任务引起的失活范式2,3。据推测，需要内部（ 即静息状态）和外部（ 例如任务相关的活动）的需求之间的平衡，以维持健康的大脑功能3-5。 以下部分提供了三种方法来研究DMN的简要概述:功能连接和任务相关的失活，其次是结构的连接。这三种方法都是递减ribed作为补充的方式到该网络的临床标本，如患者创伤后应激障碍和相关精神疾病的表征。 静息状态下DMN功能连接静息状态下的功能连接最近已成为用来评估在没有任务要求的基线脑功能模式的常用方法。功能连接是一个解析方法，量化的连贯性，或同步的程度血氧水平依赖（BOLD）的信号随着时间的推移，在不同的脑区。研究文献越来越多表明的DMN连接的典型模式可能会改变在临床和高危人群，尤其是那些以前接触显著压力或创伤。最常见的发现已减少创伤后应激障碍相关的6 DMN的静息状态功能连接。这减少的连接可能甲肝e直的临床应用，降低DMN连接可能会与预测急性应激七日后谁可能发展创伤后应激障碍。缩水DMN功能连接可以被解释的几种方法，最常用的，它反映参与自我加工的关键脑区，这可能导致无法重新分配内部资源从基线DMN处理外部需求之间差的通信。这对网络的干扰可以解释精神疾病如创伤后应激障碍和其他与压力相关的精神疾病8核心的临床症状。进一步调查这些中断的病因是未来研究的一个重要领域。 从更全面的角度，考察了DMN的功能连接的优点包括相对容易实施和健康对照组静息状态功能连接的一个强大的模式，允许一个比较可靠9,10 </s了&gt;。因此，这种方法已被开发成的应力相关的精神障碍容易实现和鲁棒神经成像的生物标记，通知大脑如何功能在没有与创伤后应激障碍以及其他应激相关的精神病症的个体的特定任务的需求的潜力。 任务相关DMN中停用在工作​​记忆（WM）检查DMN响应提供了另一种方法来研究这个网络的超越静息状态下的同步功能和功能障碍。这种做法，这反映了一种更标准的功能性磁共振成像（fMRI）方法，提供了有关回应，可能有临床意义11任务要求不同的信息。以往的研究已经证明，与会者与创伤后应激障碍证明受损的WM运作，并在WM任务更大程度的DMN停用的，这也许反映出增加认知努力12-15。 USI吴WM作为FMRI的挑战有以下几个优点。例如，它可靠地脱开几个关键DMN的区域，从静止到起动状态。最相关的创伤后应激障碍和其他与压力相关的精神疾病，西医任务可靠地脱开MPFC，参与失调的创伤后应激障碍的关键途径，主要的前DMN节点。它已经确立了内侧前额叶上行调制杏仁核活动，并有可能在扮演着恐惧条件16了至关重要的作用。内侧前额叶活动的评估，也可能是在未来的临床护理一个有用的指标。例如，在创伤的警察之一先前的研究中，暴露心理增加内侧前额叶的活动，并在创伤性记忆提取降低杏仁核活动。这些神经影像学改变与下降PSTD症状17。中西医诱发MPFC的停用这种情况下，只有一个神经影像学指标如何应用到临床人群的例子，并进一步探索其他DMN成分很可能是未来研究的一个富有成效的领域。 在这个协议中，言语工作记忆在n-back任务时使用。在n-back任务被广泛应用于FMRI研究，并且提供执行激活和默认模式网络去激活区域18,19的可靠的活化。这个任务包括三个组成部分，一个0回字母警觉任务，工作记忆和静止的基线进行比较的2-back任务。在0回警戒任务，参加者回答"是"时，预定的目标辅音（"H"或"H"）出现了，"不"使用的是两键的反应盒，而在扫描仪内其他辅音。 9辅音六0回控制块这个任务过程中提出。在2回，一系列辅音在视觉上呈现为每500毫秒，与2500毫秒的刺激间隔。与会者做出"是"或"否"响应，在每个辅音呈现，以指示它是否是相同或不同的从辅音中的一系列（ 例如 ，，W，N，R，N，R，Q，R，Q，N，W 等提出了两个先前。 ，用粗体显示正确答案）。在2回，六45秒系列15个辅音介绍。执行成功的参与者必须保持一个苛刻的认知集，其中包括恒音素缓冲（ 即 ，持有辅音在短期记忆），subvocal音素彩排（ 即 ，重复辅音没有阐明出声），和执行协调。在这两个0 - 和2 - 背块，演示的速度是一样的，目标的33％都在随机位置，大小写是随机的鼓励言语编码。一个30秒的休息基线十字注视点呈现之前，每个0回块;该基准是用于subsequ任务相关活动的耳鼻喉科比较期间的数据分析与基线相比。 两者合计，现存的数据表明任务相关DMN活动的过程中的各种任务的表征可以在临床上使用的功能DMN分析中发挥重要作用。还有其他的优势，使用WM作为应激相关精神疾病的功能磁共振成像的挑战。类似于静止状态的连接，有DMN停用的WM期间在健康个体图案清晰，这有利于比较与临床标本。 WM也外伤中立，这可能避免在扫描过程中引发创伤后应激障碍的临床症状。因此，这种方法也有反映大脑如何回应在应激相关精神障碍的外部需求将发展成为一个神经成像生物标志物的潜力。 DMN的结构连接虽然功能成像能够描述变化与应激暴露相关的大脑连接或活动秒，功能的方法没有描述后面观察大脑变化的病因。构造成像方法，如扩散张量成像（DTI），能够测量和量化的白质连接脑区的完整性。 DTI是最常见的结构性神经影像学的方法和措施，脑白质完整性的基础上，各向异性（ 即方向）流动的水分子沿白质束，因为水的流动主要是沿着白质束（比起跨过它们）。定向流量这种差异表现为各向异性分数（FA）。低度FA的被认为是反映在白质微观结构的变化，这可能是神经元损伤的表现从多种原因引起，包括应力曝光4的后果。从网络的角度来看，脑的协调活动（ 即静息状态下的活动或COORdinated任务相关的活动）必须依靠结构连接。在前面的DMN结果的情况下，结构性损伤损害DMN的节点之间的通信，从而降低DMN功能连接。同样，增加的失活模式可能反映了任务就必须响应期间的皮质区更大招募微观结构损伤。相关的创伤后应激障碍和DMN，一些研究已经在扣带回20,21，这是白质束连接大脑的22大边缘结构如图减少足总杯。这很可能是利用跟踪技术（ 即直接在神经元层面追查白质束）更精确的措施将能够阐明具体是哪个白质纤维都参与了网络中断。的优势，DTI成像是，它是比较容易获得，因为没有必要的任务，扫描仪执行。 在FOllowing协议，静息状态下的功能连接和任务诱​​发停用的定量功能的方法是结合使用DTI结构连接性的检查，以图DMN的结构和功能，并与这些发现病情的严重程度和临床相关因素的创伤后应激障碍。之前我们已经实施这种方法创伤暴露健康成人18,23后发现，该协议提供了一个令人信服的方法来表征本身会适应创伤后应激障碍的研究和其他与压力相关的精神疾病的DMN。

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developing neuroimaging phenotypes of the default mode network in ptsd: integrating the resting state, working memory, and structural connectivity

用于检查默认模式网络（DMN）互补的结构和功能神经影像学技术有可能提高精神疾病严重度评估，并提供额外的有效性的临床诊断过程。最近的神经成像研究表明，DMN的进程可能在一些与压力有关的精神疾病，如创伤后应激障碍（PTSD）的干扰。 虽然具体的DMN功能仍在调查，但一般认为是参与反省和自我处理。在健康个体中它表现在休息时间，用更少的活性，观察失活，在认知任务， 例如 ，工作记忆最伟大的活动。这个网络包括内侧前额叶皮质，后扣带回皮质/楔前叶，顶叶外侧皮质和颞区。 多重功能和结构的想象力纳克的方法已被开发，研究DMN。这些都空前的潜力，进一步这个网络的功能和功能障碍的认识。功能性的方法，如静息状态下连接和任务引起的失活的评估，具有良好的潜力，以确定有针对性的神经认知和neuroaffective（功能性）的诊断标志物和可能预示病情严重程度及预后与提高精度或特异性。结构的方法，如形态学和连通性的评价，可提供病因和长期结果的独特标记。结合，功能和结构的方法提供了强大的多模式，互补和协同的方法来开发与压力相关的精神疾病有效DMN为基础的成像表现型。该协议旨在整合这些方法在创伤后应激障碍调查DMN的结构和功能，研究结果与病情严重程度和相关的临床因素。

代表性的成果是基于使用相同的成像方法与童年创伤和虐待史个人的两个不同样本中收集到的数据，但没有创伤后应激障碍21,22。结果从静息状态功能连通性分析，揭示了空间格局与DMN的主要节点相一致（ 图1）1-3,8包括内侧前额叶，宝成，角回/下顶叶和颞中地区。这种空间分布的确认作为初始有效性检查，并允许随后的假设检验。 大脑活动的过?...

Watch this Scientific Journal Video about Developing Neuroimaging Phenotypes of the Default Mode Network in PTSD: Integrating the Resting State, Working Memory, and Structural Connectivity at JoVE.com

Developing Neuroimaging Phenotypes of the Default Mode Network in PTSD: Integrating the Resting State, Working Memory, and Structural Connectivity

This protocol describes the complementary neuroimaging techniques of resting state structural connectivity, task-induced deactivation, and structural connectivity analyses to examine the default network in post-traumatic stress disorder. The use of synergistic methods could potentially lead to improved diagnostics and assessments of severity, outcome, and other relevant clinical factors.

发展中的默认模式网络的神经影像学表型在创伤后应激障碍:整合静息状态下，工作记忆和结构连接

Complementary structural and functional neuroimaging techniques used to examine the Default Mode Network (DMN) could potentially improve assessments of ...

developing-neuroimaging-phenotypes-default-mode-network-ptsd

Research

JoVE Journal

Medicine

14.9K 次观看.  Alpert Medical School, Brown University. This protocol describes the complementary neuroimaging techniques of resting state structural connectivity, task-induced deactivation, and structural connectivity analyses to examine the default network in post-traumatic stress disorder. The use of synergistic methods could potentially lead to improved diagnostics and assessments of severity, outcome, and other relevant clinical factors.

视频: Developing Neuroimaging Phenotypes of the Default Mode Network in PTSD: Integrating the Resting State, Working Memory, and Structural Connectivity

High-frequency High-resolution Echocardiography: First Evidence on Non-invasive Repeated Measure of Myocardial Strain, Contractility, and Mitral Regurgitation in the Ischemia-reperfused Murine Heart

Ischemia-reperfusion (IR) was surgically performed in murine hearts which were then subjected to repeated imaging to monitor temporal changes in functional parameters of key clinical significance. Two-dimensional movies were acquired at high frame rate (8 kHz) and were utilized to estimate high-quality myocardial strain. Two-dimensional elastograms (strain images), as well as strain profiles, were visualized. Results were powerful in quantitatively assessing IR-induced changes in cardiac events including left-ventricular (LV) contraction, LV relaxation and isovolumetric phases of both pre-IR and post-IR beating hearts in intact mice. In addition, compromised sector-wise wall motion and anatomical deformation in the infarcted myocardium were visualized.  The elastograms were uniquely able to provide information on the following parameters in addition to standard physiological indices that are known to be affected by myocardial infarction in the mouse: internal diameters of mitral valve orifice and aorta, effective regurgitant orifice, myocardial strain (circumferential as well as radial), turbulence in blood flow pattern as revealed by the color Doppler movies and velocity profiles, asynchrony in LV sector, and changes in the length and direction of vectors demonstrating slower and asymmetrical wall movement. This work emphasizes on the visual demonstration of how such analyses are performed. 

High-frequency High-resolution Echocardiography: First Evidence on Non-invasive Repeated Measure of Myocardial Strain, Contractility, and Mitral Regurgitation in the Ischemia-reperfused Murine Heart 

High frequency Doppler ultrasound is a novel technology for assessing regional myocardial function. This work presents first evidence demonstrating applicability of this versatile imaging platform for the repeated measure of myocardial strain, dp/dt, and mitral regurgitation in the ischemia-reperfused (IR) murine heart.

高频超声心动图：非侵入性的反复测量小鼠心脏缺血再灌注心肌劳损，收缩力，二尖瓣关闭不全的第一个证据

Ischemia-reperfusion (IR) was surgically performed in murine hearts which were then subjected to repeated imaging to monitor temporal changes in ...

科研

医学

Dual-mode Imaging of Cutaneous Tissue Oxygenation and Vascular Function

Accurate assessment of cutaneous tissue oxygenation and vascular function is important for appropriate detection, staging, and treatment of many health disorders such as chronic wounds. We report the development of a dual-mode imaging system for non-invasive and non-contact imaging of cutaneous tissue oxygenation and vascular function. The imaging system integrated an infrared camera, a CCD camera, a liquid crystal tunable filter and a high intensity fiber light source. A Labview interface was programmed for equipment control, synchronization, image acquisition, processing, and visualization. Multispectral images captured by the CCD camera were used to reconstruct the tissue oxygenation map. Dynamic thermographic images captured by the infrared camera were used to reconstruct the vascular function map. Cutaneous tissue oxygenation and vascular function images were co-registered through fiduciary markers. The performance characteristics of the dual-mode image system were tested in humans.

A dual-mode imaging system was developed for non-contact assessment of cutaneous tissue oxygenation and vascular function.

双模式成像，皮肤组织氧合和血管功能

Accurate assessment of cutaneous tissue oxygenation and vascular function is important for appropriate detection, staging, and treatment of many health ...

A Method for Murine Islet Isolation and Subcapsular Kidney Transplantation

Since the early pioneering work of Ballinger and Reckard demonstrating that transplantation of islets of Langerhans into diabetic rodents could normalize their blood glucose levels, islet transplantation has been proposed to be a potential treatment for type 1 diabetes 1,2. More recently, advances in human islet transplantation have further strengthened this view 1,3. However, two major limitations prevent islet transplantation from being a widespread clinical reality: (a) the requirement for large numbers of islets per patient, which severely reduces the number of potential recipients, and (b) the need for heavy immunosuppression, which significantly affects the pediatric population of patients due to their vulnerability to long-term immunosuppression. Strategies that can overcome these limitations have the potential to enhance the therapeutic utility of islet transplantation.
Islet transplantation under the mouse kidney capsule is a widely accepted model to investigate various strategies to improve islet transplantation. This experiment requires the isolation of high quality islets and implantation of islets to the diabetic recipients. Both procedures require surgical steps that can be better demonstrated by video than by text. Here, we document the detailed steps for these procedures by both video and written protocol. We also briefly discuss different transplantation models: syngeneic, allogeneic, syngeneic autoimmune, and allogeneic autoimmune.

Transplantation of isolated islets has been proposed to be a potential treatment for type 1 diabetes. Here we describe a method to isolate islets from mouse pancreata and transplant them to the subcapsular space of the kidney.

小鼠胰岛的分离和包膜下肾移植的方法

Since the early pioneering work of Ballinger and Reckard demonstrating that transplantation of islets of Langerhans into diabetic rodents could normalize ...

Biomarkers in an Animal Model for Revealing Neural, Hematologic, and Behavioral Correlates of PTSD

Identification of biomarkers representing the evolution of the pathophysiology of Post Traumatic Stress Disorder (PTSD) is vitally important, not only for objective diagnosis but also for the evaluation of therapeutic efficacy and resilience to trauma. Ongoing research is directed at identifying molecular biomarkers for PTSD, including traumatic stress induced proteins, transcriptomes, genomic variances and genetic modulators, using biologic samples from subjects' blood, saliva, urine, and postmortem brain tissues. However, the correlation of these biomarker molecules in peripheral or postmortem samples to altered brain functions associated with psychiatric symptoms in PTSD remains unresolved. Here, we present an animal model of PTSD in which both peripheral blood and central brain biomarkers, as well as behavioral phenotype, can be collected and measured, thus providing the needed correlation of the central biomarkers of PTSD, which are mechanistic and pathognomonic but cannot be collected from people, with the peripheral biomarkers and behavioral phenotypes, which can.
Our animal model of PTSD employs restraint and tail shocks repeated for three continuous days - the inescapable tail-shock model (ITS) in rats. This ITS model mimics the pathophysiology of PTSD 17, 7, 4, 10. We and others have verified that the ITS model induces behavioral and neurobiological alterations similar to those found in PTSD subjects 17, 7, 10, 9. Specifically, these stressed rats exhibit (1) a delayed and exaggerated startle response appearing several days after stressor cessation, which given the compressed time scale of the rat's life compared to a humans, corresponds to the one to three months delay of symptoms in PTSD patients (DSM-IV-TR PTSD Criterian D/E 13), (2) enhanced plasma corticosterone (CORT) for several days, indicating compromise of the hypothalamopituitary axis (HPA), and (3) retarded body weight gain after stressor cessation, indicating dysfunction of metabolic regulation.
The experimental paradigms employed for this model are: (1) a learned helplessness paradigm in the rat assayed by measurement of acoustic startle response (ASR) and a charting of body mass; (2) microdissection of the rat brain into regions and nuclei; (3) enzyme-linked immunosorbent assay (ELISA) for blood levels of CORT; (4) a gene expression microarray plus related bioinformatics tools 18. This microarray, dubbed rMNChip, focuses on mitochondrial and mitochondria-related nuclear genes in the rat so as to specifically address the neuronal bioenergetics hypothesized to be involved in PTSD.

We describe a rat model of post traumatic stress disorder (PTSD) that reveals the persistent alterations in neuroendocrine function and the delayed long-term, exaggerated fear response, characteristic of PTSD patients. The animal model and methods described here are useful for correlating biomarkers in brain nuclei, which are mechanistic but cannot be measured in patients, with biomarkers in peripheral white blood cells, which can.

在动物模型揭示神经，血液，创伤后应激障碍和行为相关因素的生物标志物

Identification of biomarkers representing the evolution of the pathophysiology of Post Traumatic Stress Disorder (PTSD) is vitally important, not only for ...

NADH Fluorescence Imaging of Isolated Biventricular Working Rabbit Hearts

Since its inception by Langendorff1, the isolated perfused heart remains a prominent tool for studying cardiac physiology2. However, it is not well-suited for studies of cardiac metabolism, which require the heart to perform work within the context of physiologic preload and afterload pressures. Neely introduced modifications to the Langendorff technique to establish appropriate left ventricular (LV) preload and afterload pressures3. The model is known as the isolated LV working heart model and has been used extensively to study LV performance and metabolism4-6. This model, however, does not provide a properly loaded right ventricle (RV). Demmy et al. first reported a biventricular model as a modification of the LV working heart model7, 8. They found that stroke volume, cardiac output, and pressure development improved in hearts converted from working LV mode to biventricular working mode8. A properly loaded RV also diminishes abnormal pressure gradients across the septum to improve septal function. Biventricular working hearts have been shown to maintain aortic output, pulmonary flow, mean aortic pressure, heart rate, and myocardial ATP levels for up to 3 hours8.
When studying the metabolic effects of myocardial injury, such as ischemia, it is often necessary to identify the location of the affected tissue. This can be done by imaging the fluorescence of NADH (the reduced form of nicotinamide adenine dinucleotide)9-11, a coenzyme found in large quantities in the mitochondria. NADH fluorescence (fNADH) displays a near linearly inverse relationship with local oxygen concentration12 and provides a measure of mitochondrial redox state13. fNADH imaging during hypoxic and ischemic conditions has been used as a dye-free method to identify hypoxic regions14, 15 and to monitor the progression of hypoxic conditions over time10.
The objective of the method is to monitor the mitochondrial redox state of biventricular working hearts during protocols that alter the rate of myocyte metabolism or induce hypoxia or create a combination of the two. Hearts from New Zealand white rabbits were connected to a biventricular working heart system (Hugo Sachs Elektronik) and perfused with modified Krebs-Henseleit solution16 at 37 &deg;C. Aortic, LV, pulmonary artery, and left &amp; right atrial pressures were recorded. Electrical activity was measured using a monophasic action potential electrode. To image fNADH, light from a mercury lamp was filtered (350&plusmn;25 nm) and used to illuminate the epicardium. Emitted light was filtered (460&plusmn;20 nm) and imaged using a CCD camera. Changes in the epicardial fNADH of biventricular working hearts during different pacing rates are presented. The combination of the heart model and fNADH imaging provides a new and valuable experimental tool for studying acute cardiac pathologies within the context of realistic physiological conditions.

The objective is to monitor the mitochondrial redox state of isolated hearts within the context of physiologic preload and afterload pressures. A biventricular working rabbit heart model is presented. High spatiotemporal resolution fluorescence imaging of NADH is used to monitor the mitochondrial redox state of epicardial tissue.

NADH的荧光成像隔离双心室工作离体兔心

Since its inception by Langendorff1, the isolated perfused heart remains a prominent tool for studying cardiac physiology2. However, it is not well-suited ...

Identification of Disease-related Spatial Covariance Patterns using Neuroimaging Data

The scaled subprofile model (SSM)1-4 is a multivariate PCA-based algorithm that identifies major sources of variation in patient and control group brain image data while rejecting lesser components (Figure 1). Applied directly to voxel-by-voxel covariance data of steady-state multimodality images, an entire group image set can be reduced to a few significant linearly independent covariance patterns and corresponding subject scores. Each pattern, termed a group invariant subprofile (GIS), is an orthogonal principal component that represents a spatially distributed network of functionally interrelated brain regions. Large global mean scalar effects that can obscure smaller network-specific contributions are removed by the inherent logarithmic conversion and mean centering of the data2,5,6. Subjects express each of these patterns to a variable degree represented by a simple scalar score that can correlate with independent clinical or psychometric descriptors7,8. Using logistic regression analysis of subject scores (i.e. pattern expression values), linear coefficients can be derived to combine multiple principal components into single disease-related spatial covariance patterns, i.e. composite networks with improved discrimination of patients from healthy control subjects5,6. Cross-validation within the derivation set can be performed using bootstrap resampling techniques9. Forward validation is easily confirmed by direct score evaluation of the derived patterns in prospective datasets10. Once validated, disease-related patterns can be used to score individual patients with respect to a fixed reference sample, often the set of healthy subjects that was used (with the disease group) in the original pattern derivation11. These standardized values can in turn be used to assist in differential diagnosis12,13 and to assess disease progression and treatment effects at the network level7,14-16. We present an example of the application of this methodology to FDG PET data of Parkinson's Disease patients and normal controls using our in-house software to derive a characteristic covariance pattern biomarker of disease.

Multivariate techniques including principal component analysis (PCA) have been used to identify signature patterns of regional change in functional brain images. We have developed an algorithm to identify reproducible network biomarkers for the diagnosis of neurodegenerative disorders, assessment of disease progression, and objective evaluation of treatment effects in patient populations.

鉴定的使用神经影像学数据的与疾病-相关的的空间协方差模式

The scaled subprofile model (SSM)1-4 is a multivariate PCA-based algorithm that identifies major sources of variation in patient and control group brain ...

Permanent Cerebral Vessel Occlusion via Double Ligature and Transection

Stroke is a leading cause of death, disability, and socioeconomic loss worldwide. The majority of all strokes result from an interruption in blood flow (ischemia) 1. Middle cerebral artery (MCA) delivers a great majority of blood to the lateral surface of the cortex 2, is the most common site of human stroke 3, and ischemia within its territory can result in extensive dysfunction or death 1,4,5. Survivors of ischemic stroke often suffer loss or disruption of motor capabilities, sensory deficits, and infarct. In an effort to capture these key characteristics of stroke, and thereby develop effective treatment, a great deal of emphasis is placed upon animal models of ischemia in MCA.
Here we present a method of permanently occluding a cortical surface blood vessel. We will present this method using an example of a relevant vessel occlusion that models the most common type, location, and outcome of human stroke, permanent middle cerebral artery occlusion (pMCAO). In this model, we surgically expose MCA in the adult rat and subsequently occlude via double ligature and transection of the vessel. This pMCAO blocks the proximal cortical branch of MCA, causing ischemia in all of MCA cortical territory, a large portion of the cortex. This method of occlusion can also be used to occlude more distal portions of cortical vessels in order to achieve more focal ischemia targeting a smaller region of cortex. The primary disadvantages of pMCAO are that the surgical procedure is somewhat invasive as a small craniotomy is required to access MCA, though this results in minimal tissue damage. The primary advantages of this model, however, are: the site of occlusion is well defined, the degree of blood flow reduction is consistent, functional and neurological impairment occurs rapidly, infarct size is consistent, and the high rate of survival allows for long-term chronic assessment.

Permanent Cerebral Vessel Occlusion via Double Ligature and Transection

We describe a highly reproducible method for the permanent occlusion of a rodent major cerebral blood vessel. This technique can be accomplished with very little peripheral damage, minimal blood loss, a high rate of long-term survival, and consistent infarct volume commensurate with the human clinical population.

永久性脑血管闭塞<em&gt;通过</em&gt;双人结扎横断

Stroke is a leading cause of death, disability, and socioeconomic loss worldwide. The majority of all strokes result from an interruption in blood flow ...

Network Analysis of the Default Mode Network Using Functional Connectivity MRI in Temporal Lobe Epilepsy

Functional connectivity MRI (fcMRI) is an fMRI method that examines the connectivity of different brain areas based on the correlation of BOLD signal fluctuations over time. Temporal Lobe Epilepsy (TLE) is the most common type of adult epilepsy and involves multiple brain networks. The default mode network (DMN) is involved in conscious, resting state cognition and is thought to be affected in TLE where seizures cause impairment of consciousness. The DMN in epilepsy was examined using seed based fcMRI. The anterior and posterior hubs of the DMN were used as seeds in this analysis. The results show a disconnection between the anterior and posterior hubs of the DMN in TLE during the basal state. In addition, increased DMN connectivity to other brain regions in left TLE along with decreased connectivity in right TLE is revealed. The analysis demonstrates how seed-based fcMRI can be used to probe cerebral networks in brain disorders such as TLE.

The Default Mode Network (DMN) in Temporal Lobe Epilepsy (TLE) is analyzed in the resting state of the brain using seed-based functional connectivity MRI (fcMRI).

使用功能性磁共振成像连接在颞叶癫痫默认模式网络的网络分析

Functional connectivity MRI (fcMRI) is an fMRI method that examines the connectivity of different brain areas based on the correlation of BOLD signal ...

Collection and Extraction of Saliva DNA for Next Generation Sequencing

The preferred source of DNA in human genetics research is blood, or cell lines derived from blood, as these sources yield large quantities of high quality DNA. However, DNA extraction from saliva can yield high quality DNA with little to no degradation/fragmentation that is suitable for a variety of DNA assays without the expense of a phlebotomist and can even be acquired through the mail. However, at present, no saliva DNA collection/extraction protocols for next generation sequencing have been presented in the literature. This protocol optimizes parameters of saliva collection/storage and DNA extraction to be of sufficient quality and quantity for DNA assays with the highest standards, including microarray genotyping and next generation sequencing.

DNA extraction from saliva can provide a readily available source of high molecular weight DNA, with little to no degradation/fragmentation. This protocol provides optimized parameters for saliva collection/storage and DNA extraction to be of sufficient quality and quantity for downstream DNA assays with high quality requirements.

收集和唾液DNA提取用于新一代测序

The preferred source of DNA in human genetics research is blood, or cell lines derived from blood, as these sources yield large quantities of high quality ...

State of the Art Cranial Ultrasound Imaging in Neonates

Cranial ultrasound (CUS) is a reputable tool for brain imaging in critically ill neonates. It is safe, relatively cheap and easy to use, even when a patient is unstable. In addition it is radiation-free and allows serial imaging. CUS possibilities have steadily expanded. However, in many neonatal intensive care units, these possibilities are not optimally used. We present a comprehensive approach for neonatal CUS, focusing on optimal settings, different probes, multiple acoustic windows and Doppler techniques. This approach is suited for both routine clinical practice and research purposes. In a live demonstration, we show how this technique is performed in the neonatal intensive care unit. Using optimal settings and probes allows for better imaging quality and improves the diagnostic value of CUS in experienced hands. Traditionally, images are obtained through the anterior fontanel. Use of supplemental acoustic windows (lambdoid, mastoid, and lateral fontanels) improves detection of brain injury. Adding Doppler studies allows screening of patency of large intracranial arteries and veins. Flow velocities and indices can be obtained. Doppler CUS offers the possibility of detecting cerebral sinovenous thrombosis at an early stage, creating a window for therapeutic intervention prior to thrombosis-induced tissue damage. Equipment, data storage and safety aspects are also addressed.

Cranial ultrasound (CUS) is a valuable tool for brain imaging in critically ill neonates. This video shows a comprehensive approach for neonatal (Doppler) CUS for both clinical and research purposes, including a bedside demonstration of the technique.

艺术颅超声成像在新生儿的状态

Cranial ultrasound (CUS) is a reputable tool for brain imaging in critically ill neonates. It is safe, relatively cheap and easy to use, even when a ...