Name: in vivo tracking of edema development and microvascular pathology in a model of experimental cerebral malaria using magnetic resonance imaging
Uploaded: 2017-06-08T12:30:00.000+00:00
Duration: 9 min 4 s
Description: Watch this Scientific Journal Video about In Vivo Tracking of Edema Development and Microvascular Pathology in a Model of Experimental Cerebral Malaria Using Magnetic Resonance Imaging at JoVE.com

衷心感谢Miriam Reinig的专家技术援助。 AH由海德堡大学医学院的博士后补助金资助。 MP由Else-Kröner-Fresenius基金会的纪念津贴支持。 AKM是德国感染研究中心（DZIF）DZIF学院的产假津贴的获得者。 JP是海德堡分子医学研究中心（HRCMM）职业发展奖学金的获得者。我们进一步感谢Julia M. Sattler和Friedrich Frischknecht提供了子孢子运动的典型电影。

本文中报道的所有动物实验均根据实验动物科学协会联合会（FELASA）B类和实验动物科学学会（GV-SOLAS）标准指南进行，并得到当地德国当局在卡尔斯鲁厄（卡尔斯鲁厄大学（RegierungspräsidiumKarlsruhe） ，德国）。请注意，生物安全级别2适用于蚊子和Bermhei疟原虫ANKA子孢子工作。 感染<ol><li>通过在拜访模式鼠标上喂养15分钟来感染按摩皂甙Stephensi蚊子与Berghei ANKA 疟原虫 。将感染的蚊子保持在80％湿度和21°C。 </li><li>在血餐后17天至22天，从笼子里收集女性蚊子。将它们放在冰上麻醉它们。 </li><li>使用镊子，将三至四只蚊子放在载有一滴冷RPMI培养基的玻片上。将幻灯片放在显微镜下。 </li> &lt;li&gt;使用镊子，小心翼翼地伸展头部和身体之间的蚊子。使用注射器和针头分离唾液腺。用剩余的蚊子重复这个步骤。 </li><li>通过用玻璃移液管吸取玻璃移液管，从玻片上收集唾液腺，并将其收集在1.5 mL离心管中。 注意:根据感染率，每唾液腺通常可以获得8,000至15,000个感染性子孢子。 </li><li>约3分钟，用小的塑料棒粉碎离心管内的分离的唾液腺，以将子孢子与唾液腺组织分离。 </li><li>在1,000×g和4℃下离心3分钟以净化剩余组织中的子孢子。 </li><li>将含有子孢子（SPZ）的上清液吸移到新的离心管中，并计数Neubauer血细胞计数器中的纯化子孢子。 </li><li>通过添加ph将浓缩的子孢子浓度调整为10,000 / mL盐酸缓冲盐水。 </li><li>将总共​​1000个子孢子（0.1mL）注入近交C57BL / 6小鼠的尾静脉中以引发感染。为了方便注射，将C57BL / 6小鼠置于限制器中，并将尾巴放入温热（约37℃）的水中以帮助尾静脉的可视化; 注意:注射本身是一个简短的过程，可以在几秒钟内完成。 </li><li>每天一次，在SPZ感染后，从第3天开始，检查血液涂片上的血液寄生虫血症。 注意:监测寄生虫血症以前在Mueller 等人的JoVE文章中可视化。 8 </li><li>从子孢子注射后的第5天开始，用Rapid Murine Coma and Behavior Scale（RMCBS）评分每日一次。 注意:Caroll 等人已经发表了此程序的详细描述，包括视频演示。 6 </li><li>评估根据RMCBS评分的MRI成像小鼠和研究问题需要解决。 6 </li></ol>磁共振成像设置<ol><li>使用用于射频传输的音量谐振器和4通道相控阵表面接收器线圈在9.4T小型动物扫描仪上进行MRI。将温度控制的水浴打开至42°C，以保持鼠标的体温。 </li><li>在室内使用2％异氟烷和压缩空气诱导麻醉，直到鼠标不再对脚趾反应。维持麻醉1-1.5％。 </li><li>将尾静脉导管放入小鼠的尾静脉。将鼠标放置在MRI上，并将其放置在装有头锁和牙杆的动物床上，以尽量减少头部运动。注意不要拉直老鼠的颈椎。 </li><li>将造影剂注射系统连接到尾静脉导管。使用填充有Gd-DTPA（0.3 mmol / kg）注射器的定制注射系统，或使用连接到Gd-DTPA（0.3 mmol / kg）注射器的PE管。 </li><li>将双酚茴香眼膏用于双眼。将4通道相控阵表面接收头线圈放置在鼠标头上。将呼吸垫放在鼠标背面并将其连接到呼吸监测装置上。 </li></ol>成像协议注意:根据要解决的研究问题，从下面列出的协议中选择成像序列。所有列出的参数对MRI软件有效，但如果使用其他软件程序，则可能需要进行调整。 <ol><li>首先进行本地化扫描，以确保鼠标的大脑位于磁铁的等中心。 </li><li> 为了定性评估血管性水肿，通过​​选择多切片RARE序列，使用3D T2加权成像。 <ol><li>输入以下pa参考MRI软件:重复时间= 2.000 ms，回波时间= 22 ms，各向同性分辨率= 0.1mm，视场= 20 x 10 x 12 mm 3 ;矩阵= 200×100×120，翻转角= 90〜180°; （自旋回波），稀有因子= 8.启动序列，等待10分48秒获取原始图像。 </li></ol></li><li> 定量评估血管性水肿，通过​​选择多切片多自旋回波序列来进行T2松弛度测定。 <ol><li>使用以下参数:重复时间= 3.100 ms，回波时间= 8-136 ms，增量为8 ms，切片数为17，切片厚度= 0.7 mm，平面分辨率= 0.116 mm x 0.116 mm，视场20 x 20 mm 2 ，矩阵= 172 x 172，翻转角= 90-180度; （自旋回波）。启动序列，等待8分53秒获取原始图像。 </li></ol></li><li> 为了定量评估血管性水肿和细胞毒性水肿，进行扩散加权成像/表观扩散系统通过选择自旋回波EPI扩散序列来实现（ADC）映射。 <ol><li>使用以下参数:重复时间= 3.400ms，回波时间= 20ms，切片厚度= 0.7mm，切片数= 17，扩散敏化方向数= 30，b值= 1.500s / mm 2 ，δ= 3ms ，Δ= 9ms，部分傅里叶编码加速因子= 1.51，视场= 12×15mm 2 ，矩阵= 96×128，平面内分辨率= 0.125mm×0.117mm，翻转角= 90-180度，以及饱和片数（矢状）= 1.启动序列，等待7分56秒，直到获取原始图像。 </li></ol></li><li> 评估微血肿，使用3D T2 *加权成像。选择流量补偿FLASH序列。 <ol><li>在MRI软件中输入以下参数:重复时间= 2.000 ms，回波时间= 22 ms，各向同性分辨率0.08 mm，视场= 32 x 15 x 8 mm 3 ，矩阵大小= 400 x 188 x 100，f唇角= 12度。启动序列，等待15分40秒获取原始图像。 </li></ol></li><li> 为了评估动脉通畅，通过选择3D FLASH序列来使用飞行时间血管造影。 <ol><li>在MRI软件中使用以下参数:重复时间= 16 ms，回波时间= 3.5 ms，切片厚度= 0.07 mm，平面内分辨率= 0.104 x 0.104 mm，视场= 20 x 20 x 10 mm 3 ，矩阵= 192×192×142，翻转角= 15度。启动序列并等待7分钟16秒直到获取图像。 </li></ol></li><li> 为了评估血脑屏障破坏，在造影剂注射0.3 mmol / kg之前和之后使用3D T1加权成像。选择具有全球射频激励的射频损坏FLASH序列。 <ol><li>在MRI软件中使用以下序列参数:重复时间= 5 ms，回波时间= 1.9 ms，各向同性分辨率= 0.156 mm，视场20 x 18.7×18.7mm 3 ，矩阵128×120×120，翻转角= 8.5°。启动序列并等待1分14秒，直到获取图像。 </li></ol></li></ol>图像处理与分析<ol><li>为了分析血脑屏障破坏，使用ImageJ中的算术工具或图像计算器工具从增强型T1加权图像中减去3D非增强T1加权图像。评估减法图像以增加信号，这对应于血脑屏障破坏。 9 </li><li>要分析大脑体积，请使用本机3D T1-或3D T2加权数据集。使用分割编辑器将大脑从嗅球描绘成小脑。 10 </li><li> 血管性水肿 <ol><li>用MRI软件处理T2松弛度数据或使用非线性最小二乘法拟合程序。 11使用MRI sof处理扩散加权数据以获得ADC图tware或FDT工具箱（请参阅材料表 ）。 </li><li>将感兴趣区域手动放置到不同的解剖区域。 注意:感兴趣区域的自动放置可能由于显着的大脑肿胀而不正确地注册。以这种方式获得所选解剖区域的T2时间和ADC值。 </li></ol></li><li>为了分析微出血体积，使用分割编辑器描绘在T2 *加权数据集上显示为卵形，黑色焦点的微出血。 </li></ol>

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The authors declare that they have no conflicts of interest.

在本文中，我们描述了一个全脑MRI方案来描绘实验性脑疟疾的变化。我们认为迄今为止，疟疾研究中MRI尚未得到充分利用，希望我们的方案能够帮助其他调查人员。我们想描述一些可能有帮助的附加要点。 如果严重恶心的小鼠成像，定位至关重要。由于颅内压升高，小鼠易死亡，因此颈椎不应伸展。麻醉也应保持在最低限度。如果轻度疾病的小鼠成像，MRI的最佳时间点是在?...

疟疾是一个重大的全球健康问题。 1严重疟疾的特征部分是脑受累，往往是不良预后因素。疟疾传播高的地区，五岁以下儿童的脑梗死是常见的，并且是该年龄组疟疾相关死亡的主要原因。 1虽然积极的治疗可以挽救生命，但是特别是早期阶段的脑疟疾检测可能很困难。涉及脑疟疾的病理过程包括微血管破裂和脑水肿，可导致严重的脑肿胀。在本文中，我们提出了磁共振成像（MRI）协议，允许全脑脑实验性脑疟疾（ECM） 体内成像。全脑高分辨率成像方法在这种疾病中已经广泛利用不足，尽管对ECM如何在中枢起搏方面知之甚少神经系统或什么具体机制导致疾病。涵盖全脑的体内 MRI代表了一种重要的研究工具，可以更好地了解ECM病理学。 MRI能够评估全球大脑脑肿胀，最近已经被认为是ECM的重要预测因子，也是人脑疟疾的重要预测因素。 2，3严重的脑肿胀发生在致命疾病中，代表了ECM模型与人类疾病之间的几种病理特征之一，其特征是炎症和微血管改变。 4 可以通过感染致死的疟原虫疟原虫ANKA在CBA或C57BL小鼠中诱导ECM 。 ECM的发病通常发生在感染后6天和10天之间，并且导致拟合，共济失调，呼吸窘迫和昏迷，这导致说唱id死亡。 4快速鼠类昏迷和行为量表（RMCBS）是评估ECM临床症状的有益成绩。它由10个参数组成，每个评分从0到2，最大可能得分为20. 6最近，我们在ECM小鼠中RMCBS评分的严重程度和MRI证实的病理变化之间表现出良好的一致性。 7在本协议中，我们描述了小鼠的ECM诱导和ECM小鼠的体内磁共振成像。

<table><tbody><tr><td>Isoflurane</td><td>Baxter</td><td>1001747</td><td>for anesthesia</td></tr><tr><td>Dotarem</td><td>Guebert</td><td>1086923</td><td>Gd-DTPA contrast agent; 0.5 mmol/mL</td></tr><tr><td>Amira (Image Processing Program)</td><td>FEI Group</td><td></td><td>Version Amira 5.3.2</td></tr><tr><td>MATLAB&amp;nbsp;</td><td>The MathWorks, Inc.,</td><td></td><td>Release 2012b</td></tr><tr><td>FDT toolbox&amp;nbsp;</td><td>FMRIB&#039;s Software Library</td><td>&lt;a href=&quot;http://www.fmrib.ox.ac.uk/fsl/fdt/index.html&quot;&gt;http://www.fmrib.ox.ac.uk/fsl/fdt/index.html&lt;/a&gt;</td><td></td></tr></tbody></table>

in vivo tracking of edema development and microvascular pathology in a model of experimental cerebral malaria using magnetic resonance imaging

Cerebral malaria is a sign of severe malarial disease and is often a harbinger of death. While aggressive management can be life-saving, the detection of cerebral malaria can be difficult. We present an experimental mouse model of cerebral malaria that shares multiple features of the human disease, including edema and microvascular pathology. Using magnetic resonance imaging (MRI), we can detect and track the blood-brain barrier disruption, edema development, and subsequent brain swelling. We describe multiple MRI techniques that can visualize these pertinent pathological changes. Thus, we show that MRI represents a valuable tool to visualize and track pathological changes, such as edema, brain swelling, and microvascular pathology, in vivo.

在C57BL / 6小鼠中，可以观察到ECM的第一临床症状，在用Berghei ANKA子孢子感染后的第 6天和第10天之间。 ECM在60-80％的感染小鼠中发展，并在24至48小时内迅速进入昏迷和死亡。相比之下，不会发展ECM的小鼠在感染后第二周因死于高血糖症严重贫血而死亡。 12 在MRI成像中，ECM的最早的迹象在嗅球中是...

Watch this Scientific Journal Video about In Vivo Tracking of Edema Development and Microvascular Pathology in a Model of Experimental Cerebral Malaria Using Magnetic Resonance Imaging at JoVE.com

In Vivo Tracking of Edema Development and Microvascular Pathology in a Model of Experimental Cerebral Malaria Using Magnetic Resonance Imaging

We describe a mouse model of experimental cerebral malaria and show how inflammatory and microvascular pathology can be tracked in vivo using magnetic resonance imaging.

使用磁共振成像实验性脑疟疾模型中的水肿发育​​和微血管病理学的体内追踪

Cerebral malaria is a sign of severe malarial disease and is often a harbinger of death. While aggressive management can be life-saving, the detection of ...

in-vivo-tracking-edema-development-microvascular-pathology-model

Research

JoVE Journal

Medicine

In Vivo Tracking of Edema Development and Microvascular Pathology in a Model of Experimental Cerebral Malaria Using Magnetic Resonance Imaging

6.4K 次观看.  Heidelberg University Hospital. We describe a mouse model of experimental cerebral malaria and show how inflammatory and microvascular pathology can be tracked in vivo using magnetic resonance imaging. 

视频: In Vivo Tracking of Edema Development and Microvascular Pathology in a Model of Experimental Cerebral Malaria Using Magnetic Resonance Imaging

Intravital Microscopy of the Mouse Brain Microcirculation using a Closed Cranial Window

This experimental model was designed to assess the mouse pial microcirculation during acute and chronic, physiological and pathophysiological hemodynamic, inflammatory and metabolic conditions, using in vivo fluorescence microscopy. A closed cranial window is placed over the left parieto-occipital cortex of the mice. Local microcirculation is recorded in real time through the window using epi and fluorescence illumination, and measurements of vessels diameters and red blood cell (RBC) velocities are performed. RBC velocity is measured using real-time cross-correlation and/or fluorescent-labeled erythrocytes. Leukocyte and platelet adherence to pial vessels and assessment of perfusion and vascular leakage are made with the help of fluorescence-labeled markers such as Albumin-FITC and anti-CD45-TxR antibodies. Microcirculation can be repeatedly video-recorded over several days. We used for the first time the close window brain intravital microscopy to study the pial microcirculation to follow dynamic changes during the course of Plasmodium berghei ANKA infection in mice and show that expression of CM is associated with microcirculatory dysfunctions characterized by vasoconstriction, profound decrease in blood flow and eventually vascular collapse.

Intravital microscopy to follow temporal and spatial hemodynamic and inflammatory events in the pial microcirculation.

活体鼠脑微循环显微镜使用一个封闭的颅窗口

This experimental model was designed to assess the mouse pial microcirculation during acute and chronic, physiological and pathophysiological hemodynamic, ...

科研

神经科学

Intravital Microscopy of the Spleen: Quantitative Analysis of Parasite Mobility and Blood Flow

The advent of intravital microscopy in experimental rodent malaria models has allowed major advances to the knowledge of parasite-host interactions 1,2. Thus, in vivo imaging of malaria parasites during pre-erythrocytic stages have revealed the active entrance of parasites into skin lymph nodes 3, the complete development of the parasite in the skin 4, and the formation of a hepatocyte-derived merosome to assure migration and release of merozoites into the blood stream 5. Moreover, the development of individual parasites in erythrocytes has been recently documented using 4D imaging and challenged our current view on protein export in malaria 6. Thus, intravital imaging has radically changed our view on key events in Plasmodium development. Unfortunately, studies of the dynamic passage of malaria parasites through the spleen, a major lymphoid organ exquisitely adapted to clear infected red blood cells are lacking due to technical constraints.
Using the murine model of malaria Plasmodium yoelii in Balb/c mice, we have implemented intravital imaging of the spleen and reported a differential remodeling of it and adherence of parasitized red blood cells (pRBCs) to barrier cells of fibroblastic origin in the red pulp during infection with the non-lethal parasite line P.yoelii 17X as opposed to infections with the P.yoelii 17XL lethal parasite line 7. To reach these conclusions, a specific methodology using ImageJ free software was developed to enable characterization of the fast three-dimensional movement of single-pRBCs. Results obtained with this protocol allow determining velocity, directionality and residence time of parasites in the spleen, all parameters addressing adherence in vivo. In addition, we report the methodology for blood flow quantification using intravital microscopy and the use of different colouring agents to gain insight into the complex microcirculatory structure of the spleen. 
Ethics statement
All the animal studies were performed at the animal facilities of University of Barcelona in accordance with guidelines and protocols approved by the Ethics Committee for Animal Experimentation of the University of Barcelona CEEA-UB (Protocol No DMAH: 5429). Female Balb/c mice of 6-8 weeks of age were obtained from Charles River Laboratories.

We show the method for performing intravital microscopy of the spleen using GFP transgenic malaria parasites and the quantification of parasite mobility and blood flow within this organ.

活体显微镜的脾：寄生虫的流动性和血流量的定量分析

The advent of intravital microscopy in experimental rodent malaria models has allowed major advances to the knowledge of parasite-host interactions 1,2. ...

免疫与感染

Monitoring Dendritic Cell Migration using 19F / 1H Magnetic Resonance Imaging

Continuous advancements in noninvasive imaging modalities such as magnetic resonance imaging (MRI) have greatly improved our ability to study physiological or pathological processes in living organisms. MRI is also proving to be a valuable tool for capturing transplanted cells in vivo. Initial cell labeling strategies for MRI made use of contrast agents that influence the MR relaxation times (T1, T2, T2*) and lead to an enhancement (T1) or depletion (T2*) of signal where labeled cells are present. T2* enhancement agents such as ultrasmall iron oxide agents (USPIO) have been employed to study cell migration and some have also been approved by the FDA for clinical application. A drawback of T2* agents is the difficulty to distinguish the signal extinction created by the labeled cells from other artifacts such as blood clots, micro bleeds or air bubbles. In this article, we describe an emerging technique for tracking cells in vivo that is based on labeling the cells with fluorine (19F)-rich particles. These particles are prepared by emulsifying perfluorocarbon (PFC) compounds and then used to label cells, which subsequently can be imaged by 19F MRI. Important advantages of PFCs for cell tracking in vivo include (i) the absence of carbon-bound 19F in vivo, which then yields background-free images and complete cell selectivityand(ii) the possibility to quantify the cell signal by 19F MR spectroscopy.

Monitoring Dendritic Cell Migration using 19F / 1H Magnetic Resonance Imaging

Tracking of cells using MRI has gained remarkable attention in the past years. This protocol describes the labeling of dendritic cells with fluorine (19F)-rich particles, the in vivo application of these cells, and monitoring the extent of their migration to the draining lymph node with 19F/1H MRI and 19F MRS.

监测树突状细胞迁移<sup&gt; 19</sup&gt; F /<sup&gt; 1</sup&gt; H磁共振成像

Continuous  advancements in noninvasive imaging modalities such as magnetic resonance  imaging (MRI) have greatly improved our ability to study ...

Modeling Brain Metastases Through Intracranial Injection and Magnetic Resonance Imaging

Metastatic spread of cancer is an unfortunate consequence of disease progression, aggressive cancer subtypes, and/or late diagnosis. Brain metastases are particularly devastating, difficult to treat, and confer a poor prognosis. While the precise incidence of brain metastases in the United States remains hard to estimate, it is likely to increase as extracranial therapies continue to become more efficacious in treating cancer. Thus, it is necessary to identify and develop novel therapeutic approaches to treat metastasis at this site. To this end, intracranial injection of cancer cells has become a well-established method in which to model brain metastasis. Previously, the inability to directly measure tumor growth has been a technical hindrance to this model; however, increasing availability and quality of small animal imaging modalities, such as magnetic resonance imaging (MRI), are vastly improving the ability to monitor tumor growth over time and infer changes within the brain during the experimental period. Herein, intracranial injection of murine mammary tumor cells into immunocompetent mice followed by MRI is demonstrated. The presented injection approach utilizes isoflurane anesthesia and a stereotactic setup with a digitally controlled, automated drill and needle injection to enhance precision, and reduce technical error. MRI is measured over time using a 9.4 Tesla instrument in The Ohio State University James Comprehensive Cancer Center Small Animal Imaging Shared Resource. Tumor volume measurements are demonstrated at each time point through use of ImageJ. Overall, this intracranial injection approach allows for precise injection, day-to-day monitoring, and accurate tumor volume measurements, which combined greatly enhance the utility of this model system to test novel hypotheses on the drivers of brain metastases.

Intracranial brain metastasis modeling is complicated by an inability to monitor tumor size and response to treatment with precise and timely methods. The presented methodology couples intracranial tumor injection with magnetic resonance imaging analysis, which when combined, cultivates precise and consistent injections, enhanced animal monitoring, and accurate tumor volume measurements.

通过颅内注射和磁共振成像对大脑转移进行建模

Metastatic spread of cancer is an unfortunate consequence of disease progression, aggressive cancer subtypes, and/or late diagnosis. Brain metastases are ...

癌症研究

In vivo 19F MRI for Cell Tracking

In vivo 19F MRI allows quantitative cell tracking without the use of ionizing radiation. It is a noninvasive technique that can be applied to humans. Here, we describe a general protocol for cell labeling, imaging, and image processing. The technique is applicable to various cell types and animal models, although here we focus on a typical mouse model for tracking murine immune cells. The most important issues for cell labeling are described, as these are relevant to all models. Similarly, key imaging parameters are listed, although the details will vary depending on the MRI system and the individual setup. Finally, we include an image processing protocol for quantification. Variations for this, and other parts of the protocol, are assessed in the Discussion section. Based on the detailed procedure described here, the user will need to adapt the protocol for each specific cell type, cell label, animal model, and imaging setup. Note that the protocol can also be adapted for human use, as long as clinical restrictions are met.

In vivo 19F MRI for Cell Tracking

We describe a general protocol for in vivo cell tracking using MRI in a mouse model with ex vivo labeled cells. A typical protocol for cell labeling, image acquisition processing and quantification is included.

在体内 19女性 MRI对细胞跟踪

In vivo 19F MRI allows quantitative cell tracking without the use of ionizing radiation. It is a noninvasive technique that can be applied to humans. ...

医学

Noninvasive Assessment of Cardiac Abnormalities in Experimental Autoimmune Myocarditis by Magnetic Resonance Microscopy Imaging in the Mouse

Myocarditis is an inflammation of the myocardium, but only ~10% of those affected show clinical manifestations of the disease. To study the immune events of myocardial injuries, various mouse models of myocarditis have been widely used. This study involved experimental autoimmune myocarditis (EAM) induced with cardiac myosin heavy chain (Myhc)-&#945; 334-352 in A/J mice; the affected animals develop lymphocytic myocarditis but with no apparent clinical signs. In this model, the utility of magnetic resonance microscopy (MRM) as a non-invasive modality to determine the cardiac structural and functional changes in animals immunized with Myhc-&#945; 334-352 is shown. EAM and healthy mice were imaged using a 9.4 T (400 MHz) 89 mm vertical core bore scanner equipped with a 4 cm millipede radio-frequency imaging probe and 100 G/cm triple axis gradients. Cardiac images were acquired from anesthetized animals using a gradient-echo-based cine pulse sequence, and the animals were monitored by respiration and pulse oximetry. The analysis revealed an increase in the thickness of the ventricular wall in EAM mice, with a corresponding decrease in the interior diameter of ventricles, when compared with healthy mice. The data suggest that morphological and functional changes in the inflamed hearts can be non-invasively monitored by MRM in live animals. In conclusion, MRM offers an advantage of assessing the progression and regression of myocardial injuries in diseases caused by infectious agents, as well as response to therapies.

This study demonstrates the successful establishment of magnetic resonance microscopy imaging as a non-invasive tool to assess the cardiac abnormalities in mice affected with autoimmune myocarditis. The data indicate that the technique can be used to monitor the disease-progression in live animals.

心脏异常的实验性自身免疫性心肌炎的无创性评估磁共振成像显微镜在鼠标

Myocarditis is an inflammation of the myocardium, but only ~10% of those affected show clinical manifestations of the disease. To study the immune events ...

Assessing Cortical Cerebral Microinfarcts on High Resolution MR Images

Cerebral microinfarcts are frequent findings in the post-mortem human brain, and are related to cognitive decline and dementia. Due to their small sizes it is challenging to study them on clinical MRI scans. It was recently demonstrated that cortical microinfarcts can be depicted with MRI scanners using high magnetic field strengths (7T). Based on this experience, a proportion of these lesions is also visible on lower resolution 3T MRI. These findings were corroborated with ex vivo imaging of post-mortem human brain tissue, accompanied by histopathological verification of possible cortical microinfarcts.
Here an ex vivo imaging protocol is presented, for the purpose of validating MR observed cerebral microvascular pathology with histological evaluation. Furthermore, guidelines are provided for the assessment of cortical microinfarcts on both in vivo 7T and 3T MR images. These guidelines provide researchers with a tool to rate cortical microinfarcts on in vivo images of larger patient samples, to further unravel their clinical relevance in cognitive decline and dementia, and establish these lesions as a novel biomarker of cerebral small vessel disease.

A high resolution ex vivo 7T MR imaging protocol is presented, to perform MR-guided histopathological validation of microvascular pathology in post-mortem human brain tissue. Furthermore, guidelines are provided for the assessment of cortical microinfarcts on in vivo 7T as well as 3T MR images.

评估皮层脑Microinfarcts高分辨率核磁共振图像

Cerebral microinfarcts are frequent findings in the post-mortem human brain, and are related to cognitive decline and dementia. Due to their small sizes ...

Longitudinal In Vivo Imaging of the Cerebrovasculature: Relevance to CNS Diseases

Remodeling of the brain vasculature is a common trait of brain pathologies. In vivo imaging techniques are fundamental to detect cerebrovascular plasticity or damage occurring overtime and in relation to neuronal activity or blood flow. In vivo two-photon microscopy allows the study of the structural and functional plasticity of large cellular units in the living brain. In particular, the thinned-skull window preparation allows the visualization of cortical regions of interest (ROI) without inducing significant brain inflammation. Repetitive imaging sessions of cortical ROI are feasible, providing the characterization of disease hallmarks over time during the progression of numerous CNS diseases. This technique accessing the pial structures within 250 &#956;m of the brain relies on the detection of fluorescent probes encoded by genetic cellular markers and/or vital dyes. The latter (e.g., fluorescent dextrans) are used to map the luminal compartment of cerebrovascular structures. Germane to the protocol described herein is the use of an in vivo marker of amyloid deposits, Methoxy-O4, to assess Alzheimer&#39;s disease (AD) progression. We also describe the post-acquisition image processing used to track vascular changes and amyloid depositions. While focusing presently on a model of AD, the described protocol is relevant to other CNS disorders where pathological cerebrovascular changes occur.

Longitudinal In Vivo Imaging of the Cerebrovasculature: Relevance to CNS Diseases

This manuscript describes a procedure to track the remodeling of the cerebrovasculature during amyloid plaque accumulation in vivo using longitudinal two-photon microscopy. A thinned-skull preparation enables the visualization of fluorescent dyes to assess the progression of cerebrovascular damage in a mouse model of Alzheimer&#39;s disease.

纵<em&gt;在体内</em&gt;的Cerebrovasculature影像:相关性疾病CNS

Remodeling of the brain vasculature is a common trait of brain pathologies. In vivo imaging techniques are fundamental to detect cerebrovascular ...

Tracking Superparamagnetic Iron Oxide-labeled Mesenchymal Stem Cells using MRI after Intranasal Delivery in a Traumatic Brain Injury Murine Model

Stem cell-based therapies for brain injuries, such as traumatic brain injury (TBI), are a promising approach for clinical trials. However, technical hurdles such as invasive cell delivery and tracking with low transplantation efficiency remain challenges in translational stem-based therapy. This article describes an emerging technique for stem cell labeling and tracking based on the labeling of the mesenchymal stem cells (MSCs) with superparamagnetic iron oxide (SPIO)&#160;nanoparticles, as well as intranasal delivery of the labeled MSCs. These nanoparticles are fluorescein isothiocyanate (FITC)-embedded and safe to label the MSCs, which are subsequently delivered to the brains of TBI-induced mice by the intranasal route. They are then tracked non-invasively in vivo by real-time magnetic resonance imaging (MRI). Important advantages of this technique that combines SPIO for cell labeling and intranasal delivery include (1) non-invasive, in vivo MSC tracking after delivery for long tracking periods, (2) the possibility of multiple dosing regimens due to the non-invasive route of MSC delivery, and (3) possible applications to humans, owing to the safety of SPIO, non-invasive nature of the cell-tracking method by MRI, and route of administration.

Presented here is a protocol for non-invasive mesenchymal stem cell (MSC) delivery and tracking in a mouse model of traumatic brain injury. Superparamagnetic iron oxide&#160;nanoparticles are employed as a magnetic resonance imaging (MRI) probe for MSC labeling and non-invasive in vivo tracking following intranasal delivery using real-time MRI.

跟踪超副磁性氧化铁标记的美感血干细胞使用MRI后，创伤性脑损伤Murine模型内伤分娩

Stem cell-based therapies for brain injuries, such as traumatic brain injury (TBI), are a promising approach for clinical trials. However, technical ...

Generation of a Mouse Model of Experimental Cerebral Malaria Using Host Mosquito-Derived Sporozoites

Source: Hoffmann, A. et al., <a href="https://app.jove.com/v/55334">In Vivo&#160;Tracking of Edema Development and Microvascular Pathology in a Model of Experimental Cerebral Malaria Using Magnetic Resonance Imaging.</a>&#160;J. Vis. Exp.&#160; (2017)
This video demonstrates the generation of an experimental mouse model of cerebral malaria. Sporozoites isolated from Plasmodium berghei-infected female mosquitoes are injected into a restrained mouse&#39;s tail veins, leading to blood-brain barrier disruption and brain inflammation, causing cerebral malaria. This infected mouse model offers a valuable tool to study in vivo microvascular pathology associated with cerebral malaria.

使用宿主蚊子孢子生成实验性脑疟疾小鼠模型

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.
1. ...

使用磁共振成像实验性脑疟疾模型中的水肿发育和微血管病理学的体内追踪

摘要

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此视频中的章节

活体鼠脑微循环显微镜使用一个封闭的颅窗口

活体显微镜的脾：寄生虫的流动性和血流量的定量分析

监测树突状细胞迁移

通过颅内注射和磁共振成像对大脑转移进行建模

在体内 ^19女性 MRI对细胞跟踪

心脏异常的实验性自身免疫性心肌炎的无创性评估磁共振成像显微镜在鼠标

评估皮层脑Microinfarcts高分辨率核磁共振图像

纵

跟踪超副磁性氧化铁标记的美感血干细胞使用MRI后，创伤性脑损伤Murine模型内伤分娩

使用宿主蚊子孢子生成实验性脑疟疾小鼠模型

使用磁共振成像实验性脑疟疾模型中的水肿发育​​和微血管病理学的体内追踪

摘要

探索更多视频

此视频中的章节

活体鼠脑微循环显微镜使用一个封闭的颅窗口

活体显微镜的脾：寄生虫的流动性和血流量的定量分析

监测树突状细胞迁移

通过颅内注射和磁共振成像对大脑转移进行建模

在体内 19女性 MRI对细胞跟踪

心脏异常的实验性自身免疫性心肌炎的无创性评估磁共振成像显微镜在鼠标

评估皮层脑Microinfarcts高分辨率核磁共振图像

纵

跟踪超副磁性氧化铁标记的美感血干细胞使用MRI后，创伤性脑损伤Murine模型内伤分娩

使用宿主蚊子孢子生成实验性脑疟疾小鼠模型

使用磁共振成像实验性脑疟疾模型中的水肿发育和微血管病理学的体内追踪

在体内 ^19女性 MRI对细胞跟踪