This work was supported by grant 13IRG14560023 from the American Heart Association and NIH grants AI078972 and HL108054 to CJO. Support for AOB was from the NIH National Center for Advancing Translational Sciences NIH ULTR001120, and F31 A110417701.

注:所有小鼠实验进行了审查，并在得克萨斯健康科学中心大学圣安东尼奥（协议＃13032-34-01C）批准的机构动物护理和使用委员会。动物保健和遵守公法89-544（动物福利法）及其修正案，公共卫生服务的指导方针，以及指南实验动物的护理和使用（健康与人类服务部）的实验方案。 1.感染<ol><li>获得10-12周龄岁之间的男性和女性的BALB / c小鼠。 注:S.血清型肺炎 4个应变TIGR4是已测序的16剧毒临床分离。 </li><li>生长TIGR4中的Todd-Hewitt肉汤，在37℃在5％CO 2，直到达到一个光学密度（OD）0.5 620（对应于1.0×10 8菌落形成单位[CFU] / ml）中。颗粒通过离心肺炎球菌培养，在3 10分钟，500×g离心并除去使用真空线上清液。暂停和稀的细菌，用无菌磷酸盐缓冲盐水（PBS）以1.0×10 4 CFU / ml的终浓度。 </li><li>使用感应室，麻醉小鼠在氧气2.5％异氟烷气化。轻轻捏脚趾用生硬的镊子确认麻醉状态。 <ol><li>由它的浮渣保持了麻醉的小鼠和直立用一只手，注入每只小鼠腹膜内（IP）用100μl的S的使用注射器用27-30号针（对应于1.0×10 3 CFU一个挑战剂量） 肺炎悬浮液。将鼠标放回笼子。小鼠通常唤醒注射后30-40秒。 </li></ol></li><li>允许感染进行至少24（早期）或30（高级）小时。 <ol><li>安乐死小鼠CO 2窒息。执行颈椎脱位，确保鼠标已经死亡。安乐死是通过去除进一步证实在1.6步的心脏。 </li></ol></li><li>消毒用酒精棉签尾部操起一个2-3毫米的部分。收集2微升的血液和连续稀释血液的10倍PBS含肝素钠1 U / ml的五倍。在胰蛋白大豆血琼脂平板上平板系列稀释并在5％CO 2，从菌落第二天外推计算菌血症水平孵育过夜，在37℃。 </li><li>固定鼠标在上一个外科平台仰卧位置。喷雾胸部用70％乙醇和拍干。用手术剪刀和镊子打开胸腔，取出肋骨，和横切隔膜暴露心脏和肺部。用剪刀剪连接到心脏的血管，轻轻摘除心脏小心，避免用钳子青紫。 </li><li>冲洗PBS的心脏，然后放入组织标本收集磁带，这样冠状切片将组织切片中获得。对于石蜡包埋，解放军CE在10％缓冲的甲醛溶液和第二天卡匣发送用于石蜡包埋。 <ol><li>可替代地使用cryomold已放置在干冰上内OCT化合物闪光冻结。 </li></ol></li></ol> 2.可视化心脏病变及病变范围内的肺炎球菌<ol><li>减少石蜡包埋的心脏部分，使4室的心脏在每个组织切片可见。切载玻片在5微米厚。 </li><li> Deparaffinize和染色的幻灯片使用标准方法17苏木和伊红（H＆E）。 </li><li>视图，H＆E染色使用光学显微镜在低（100X，200X）和高（油浸:400X，1,000X）心脏切片的放大倍数。表征心中microlesions在心肌的存在。在这里，获得使用蔡司Axioskop 2显微镜配备了100X 1.3数值孔径计划，NEOFLUAR客观H＆E影像。 注:在早期心脏升esions由它们的差是有色的外观和在某些情况下的免疫细胞（单核细胞和粒细胞）什么似乎是单核细胞的存在区别。在先进的病变，尤其是在看到30小时，免疫细胞缺失和大空泡状病变在他们的地方观察。要注意的是，虽然在心肌病变发展的早期阶段的免疫细胞流入可发生不似乎是一个要求是很重要的。 </li></ol> 3.免疫荧光显微镜的范围内Microlesions肺炎球菌<ol><li>部分心脏中cryomolds用切片机以厚度为5微米，代替部分上带正电荷的载玻片上。让心脏冰冻切片解冻和空气干燥。定为10分钟，在10％的中性缓冲的福尔马林部分（pH为6.8-7.2，在25℃）。 </li><li>在PBS中5分钟洗载玻片（3×），透化在0.2％的Triton X-100的PBS中15分钟，然后在PBS中再次洗涤。 </li><li>块组织secti<html>对载玻片用1小时在PBS中的10％山羊血清。 </li><li>漂洗载玻片用PBS，盖孵育心脏切片用兔抗血清型4肺炎球菌血清在1:在37℃下在PBS 1000，用10％山羊血清2小时。 注:对于阴性对照调查人员应使用天真兔抗血清</li><li>之后用PBS洗涤，盖孵育，用10％山羊血清的PBS中的部分用山羊抗兔FITC缀合的抗体以1:在37℃2000 30分钟。 </li><li>按照制造商的指示，用DAPI（4&#39;，6-二脒基-2-苯基吲哚）以5mg / ml的真核细胞核可视化。清洗和安装组织切片与FluorSave。 </li><li>使用共聚焦显微镜系统在低和高放大倍数取得的荧光图像。调节的数值孔径相应的，以获得最佳的效果。这里，使用共聚焦系统，具有60X 1.42数值孔径物镜获取荧光图像。 </li></ol>化粪池小鼠"&gt; 4。抗生素救援<ol><li>小鼠感染IP用1.0×10 3 CFU TIGR4的开始如先前在步骤1中所示。 </li><li>在30小时后的感染开始，施用在100μl盐水药用级氨苄青霉素IP（80毫克/公斤体重），每12小时36小时。如在用于石蜡包埋和组织，切片步骤1.6中所述收集心在期望的时间点和处理。 </li></ol> 5.胶原沉积检测<ol><li>使用二甲苯和分级醇洗涤与使用标准方法17去离子水，deparaffinize和水合物的组织切片。治疗用含水0.2％磷酸部分为5分钟，并用去离子水冲洗5分钟。 </li><li>染色切片用0.1％天狼星红在苦味酸2小时，在室温下进行。 </li><li>在0.01N盐酸3分钟洗部分和漂洗用70％乙醇1分钟。 </li><li> Dehydra使用相同的TE成功的部分，但是为了反洗到5.1概括的，脱水增加心脏部分，分级乙醇浓度再二甲苯。 </li><li>摩组织切片与微观评估的安装解决方案。 </li><li>以确定胶原沉积的区域中，检查染色组织切片的深读染色使用光学显微镜在低和高放大倍数的区域。这是红色心脏的心室中的任何区域是胶原蛋白已存入的区域。如果没有这个红染色领域是健康组织的网站缺乏胶原沉积。此处，获取使用装有20X 0.5数值孔径物镜的显微镜中苦天狼红染色的图像。 注:该庭污渍红健康组织。 </li></ol>

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The authors declare no conflict of interest in this study.

在这份报告中，高度重复的方法诱导S.肺炎介导的小鼠心脏microlesions IPD期间和技术的可视化展示。小鼠感染剂量的细菌，优于通关免疫系统的门槛，导致高档菌血症，​​类似这人类败血症期间发生，并导致最终的细菌移位到心肌。对于未知的原因，S.肺炎的心脏是能够通过宿主的免疫反应来复制偏向虎山行。这是正在进行的调查的主题，本出版物可以促进其他研究者在他们的努力?...

成人社区获得性肺炎（CAP）住院进行了心脏不良事件，有助于死亡率1-4文件化的风险。在最近的一项研究科拉莱斯-Medina 等人 ，发现心脏并发症要关联有和/或负责肺炎相关死亡3的27％。 肺炎链球菌 （肺炎球菌），CAP和败血症5的最常见原因，已直接与多达19％的人承认的成人患者6心脏不良事件相关。与肺炎相关的不良心脏事件包括为了降低频率6的新的或恶化充血性心脏衰竭，心律失常和心肌梗死。 在最近的一个公共科学图书馆病原布朗等人的文章。，肺炎链球菌 ，发现通过心脏血管内皮，进入myocardiu是能够易位米，并形成独立非化脓性病变显微镜（microlesions）侵袭性肺炎球菌疾病（IPD）7时充满细菌侧脑室。观察心脏样本中心脏microlesion形成的证据来自非人类灵长类动物和个人谁曾死于肺炎球菌感染。同样，实验感染小鼠重复开发的心脏microlesions。在小鼠中，microlesion大小和数量呈正的持续时间和菌血症，心肌肌钙蛋白血清水平的严重程度，以及异常心脏电相关。细菌易位入心脏，发现发生通过负责跨越血-脑屏障和肺炎球菌性脑膜炎的发展， 也就是 ，胆碱结合蛋白A介导的血管内皮细胞的浸润在层粘连蛋白受体和血小板的肺炎球菌的易位相同的机制-activating因子受体依赖性8。 Microles离子的形成还需要肺炎球菌成孔毒素肺炎球菌被发现杀死心肌7。 肺炎球菌心脏microlesions是从由其他革兰氏阳性菌，包括金黄色葡萄球菌所引起的化脓性软组织和心脏脓肿鲜明。这些特点是由细菌中性粒细胞和纤维蛋白沉积9,10包围的单一病灶。 Microlesions由S.形成肺炎在尺寸，在整个受影响的心脏分布更小，且缺乏免疫细胞浸润。在感染的早期阶段，microlesions引起由S.肺炎表现为受损或发炎的组织让人想起心肌病的病理征象领域。一些单核细胞可能在此期间观察到，但是他们的存在是短暂的，病变迅速成为坏死在外观，充满了细菌，同时继续GR流的大小，直到动物或抗微生物干预的死亡。重要的是，内抗生素干预后3天，大量的免疫细胞浸润被观察到前者病变部位，这是伴随着强劲的胶原沉积。类似心脏重塑已报道发生对心脏功能11-15持久后果沿着以下梗死。因此，microlesions是心脏相关死亡率的恢复期个体的发病率增加谁生存了疾病发作期间的IPD和可能发生的不良心脏事件的潜在的解释。 这里，指令被设置在IPD与心肌损伤形成和心肌microlesions可视化的实验小鼠模型中，在感染的早期和晚期阶段。已保存的抗菌干预动物的协议检测胶原沉积的证明。本文的目的是至facilitate在这一重要和新颖的肺炎病理其他研究者的研究。

<table><tbody><tr><td>Todd-Hewitt broth&amp;nbsp;</td><td>Neogen</td><td>7161A</td><td></td></tr><tr><td>O.C.T Compound&amp;nbsp;</td><td>Tissue-Tek (Sakura Finetek)&amp;nbsp;</td><td>4583</td><td></td></tr><tr><td>Triton X-100&amp;nbsp;</td><td>Fisher Scientific (Acros)</td><td>9002-93-1</td><td></td></tr><tr><td>Normal Goat Serum</td><td>Abcam</td><td>ab7481</td><td></td></tr><tr><td>anti-serotype 4 pneumococcus antiserum&amp;nbsp;</td><td>Statens Serum Institut</td><td>16747</td><td></td></tr><tr><td>goat anti-rabbit FITC conjugated antibody&amp;nbsp;</td><td>Jackson ImmunoResearch</td><td>111-096-144</td><td></td></tr><tr><td>DAPI</td><td>Invitrogen</td><td>D1306</td><td></td></tr><tr><td>Fluorsave</td><td>Millipore</td><td>345789</td><td></td></tr><tr><td>Permount</td><td>Fisher Scientific</td><td>S70104</td><td></td></tr><tr><td>Ampicillin</td><td>Sigma</td><td>A9393</td><td></td></tr><tr><td>phosphomolybdic acid 0.2%&amp;nbsp;</td><td>Electron Microscopy Sciences</td><td>26357-01</td><td></td></tr><tr><td>0.1% Sirius Red in picric acid&amp;nbsp;</td><td>Electron Microscopy Sciences</td><td>26357-02</td><td></td></tr><tr><td>0.01 N hydrochloric acid&amp;nbsp;</td><td>Electron Microscopy Sciences</td><td>26357-03</td><td></td></tr><tr><td>Tissue Tack Microscope Slides</td><td>Polysciences, Inc</td><td>24216</td><td></td></tr><tr><td>Paralube Vet Ointment</td><td>Dechra</td><td>12920060</td><td></td></tr><tr><td>Hematoxylin and Eosin Staining Kit</td><td>unspeciified&amp;nbsp;</td><td></td><td>Standard</td></tr></tbody></table>

visualization of streptococcus pneumoniae within cardiac microlesions and subsequent cardiac remodeling

期间菌血症肺炎链球菌可在血管内皮转运进入心肌和形成离散菌填充微观病变（microlesions）是显着的，由于缺乏浸润免疫细胞。由于其释放心脏毒性的产品，S.肺炎 microlesions内被认为有助于向心脏衰竭是在成人中雷酸侵袭性肺炎球菌疾病中经常观察到。在此证明一个协议，用于实验的小鼠感染，导致30小时内可重复的心脏microlesion形成。设在microlesion鉴定苏木精 - 伊红染色心脏切片和早期和晚期microlesions之间的形态区别的指令被突出显示。设置在一个协议，用于验证S的指令肺炎使用抗肺炎球菌荚膜多糖和microlesions内免疫荧光显微镜。最后，提供了一种协议，用于抗生素干预拯救感染小鼠和用于检测和瘢痕形成在恢复期小鼠的心脏评估。一起，这些协议将促进肺炎球菌心脏侵袭，心肌细胞死亡，心脏重塑底层的暴露至S.的结果的分子机制的研究肺炎 ，以及在心脏的肺炎球菌的免疫应答。

Microlesions由H＆E可视化心脏microlesions观察到的H＆E染色小鼠与IPD下面的IP挑战，TIGR4心脏部分心室。 图1说明了增加24和​​30小时后感染（HPI），与这些病变的大小更多的苏木染色的（ 即 ，紫蓝色）肺炎病灶内可见。 Microlesions的特点是一个液泡样形态，更密集的曙红（红色）染色紧邻病灶部位的心肌细胞中的，病灶内双球菌，和一般缺乏免疫细胞。?...

Watch this Scientific Journal Video about Visualization of Streptococcus pneumoniae within Cardiac Microlesions and Subsequent Cardiac Remodeling at JoVE.com

Visualization of Streptococcus pneumoniae within Cardiac Microlesions and Subsequent Cardiac Remodeling

Streptococcus pneumoniae forms discrete non-purulent microscopic lesions in the heart. Outlined is the protocol for a murine model of cardiac microlesion formation. Instruction is provided on microlesion visualization using microscopy, discrimination between early and late microlesions, and methods to detect cardiac remodeling in hearts of convalescent animals.

可视化<em&gt;肺炎链球菌</em&gt;在心脏Microlesions和随后的心脏重构

During bacteremia Streptococcus pneumoniae can translocate across the vascular endothelium into the myocardium and form discrete bacteria-filled ...

visualization-streptococcus-pneumoniae-within-cardiac-microlesions

Research

JoVE Journal

Medicine

Visualization of Streptococcus pneumoniae within Cardiac Microlesions and Subsequent Cardiac Remodeling

8.9K 次观看.  The University of Texas Health Science Center at San Antonio. Streptococcus pneumoniae forms discrete non-purulent microscopic lesions in the heart. Outlined is the protocol for a murine model of cardiac microlesion formation. Instruction is provided on microlesion visualization using microscopy, discrimination between early and late microlesions, and methods to detect cardiac remodeling in hearts of convalescent animals. 

视频: Visualization of Streptococcus pneumoniae within Cardiac Microlesions and Subsequent Cardiac Remodeling

Quantitative Visualization of Leukocyte Infiltrate in a Murine Model of Fulminant Myocarditis by Light Sheet Microscopy

Light-sheet fluorescence microscopy (LSFM), in combination with chemical clearing protocols, has become the gold standard for analyzing fluorescently labelled structures in large biological specimens, and is down to cellular resolution. Meanwhile, the constant refinement of underlying protocols and the enhanced availability of specialized commercial systems enable us to investigate the microstructure of whole mouse organs and even allow for the characterization of cellular behavior in various live-cell imaging approaches. Here, we describe a protocol for the spatial whole-mount visualization and quantification of the CD45+ leukocyte population in inflamed mouse hearts. The method employs a transgenic mouse strain (CD11c.DTR)that has recently been shown to serve as a robust, inducible model for the study of the development of fulminant fatal myocarditis, characterized by lethal cardiac arrhythmias. This protocol includes myocarditis induction, intravital antibody-mediated cell staining, organ preparation, and LSFM with subsequent computer-assisted image post-processing. Although presented as a highly-adapted method for our particular scientific question, the protocol represents the blueprint of an easily adjustable system that can also target completely different fluorescent structures in other organs and even in other species.

Here, we describe a light-sheet microscopy approach to visualize the cardiac CD45+ leukocyte infiltrate in a murine model of aseptic fulminant myocarditis, which is induced by the intratracheal diphtheria toxin treatment of CD11c.DTR mice.

通过轻型显微镜对小鼠急性心肌炎模型中白细胞浸润的定量可视化

Light-sheet fluorescence microscopy (LSFM), in combination with chemical clearing protocols, has become the gold standard for analyzing fluorescently ...

科研

医学

Refined CLARITY-Based Tissue Clearing for Three-Dimensional Fibroblast Organization in Healthy and Injured Mouse Hearts

Cardiovascular disease is the most prevalent cause of mortality worldwide and is often marked by heightened cardiac fibrosis that can lead to increased ventricular stiffness with altered cardiac function. This increase in cardiac ventricular fibrosis is due to activation of resident fibroblasts, although how these cells operate within the 3-dimensional (3-D) heart, at baseline or after activation, is not well understood. To examine how fibroblasts contribute to heart disease and their dynamics in the 3-D heart, a refined CLARITY-based tissue clearing and imaging method was developed that shows fluorescently labeled cardiac fibroblasts within the entire mouse heart. Tissue resident fibroblasts were genetically labeled using Rosa26-loxP-eGFP florescent reporter mice crossed with the cardiac fibroblast expressing Tcf21-MerCreMer knock-in line. This technique was used to observe fibroblast localization dynamics throughout the entire adult left ventricle in healthy mice and in fibrotic mouse models of heart disease. Interestingly, in one injury model, unique patterns of cardiac fibroblasts were observed in the injured mouse heart that followed bands of wrapped fibers in the contractile direction. In ischemic injury models, fibroblast death occurred, followed by repopulation from the infarct border zone. Collectively, this refined cardiac tissue clarifying technique and digitized imaging system allows for 3-D visualization of cardiac fibroblasts in the heart without the limitations of antibody penetration failure or previous issues surrounding lost fluorescence due to tissue processing.

A refined method of tissue clearing was developed and applied to the adult mouse heart. This method was designed to clear dense, autofluorescent cardiac tissue, while maintaining labeled fibroblast fluorescence attributed to a genetic reporter strategy.

在健康和受伤的老鼠心脏中为三维纤维细胞组织进行精炼的清晰组织清除

Cardiovascular disease is the most prevalent cause of mortality worldwide and is often marked by heightened cardiac fibrosis that can lead to increased ...

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 ...

Tissue Preparation Techniques for Contrast-Enhanced Micro Computed Tomography Imaging of Large Mammalian Cardiac Models with Chronic Disease

Structural remodeling is a common consequence of chronic pathological stresses imposed on the heart. Understanding the architectural and compositional properties of diseased tissue is critical to determine their interactions with arrhythmic behavior. Microscale tissue remodeling, below the clinical resolution, is emerging as an important source of lethal arrhythmia, with high prevalence in young adults. Challenges remain in obtaining high imaging contrast at sufficient microscale resolution for preclinical models, such as large mammalian whole hearts. Moreover, tissue composition-selective contrast enhancement for three-dimensional high-resolution imaging is still lacking. Non-destructive imaging using micro-computed tomography shows promise for high-resolution imaging. The objective was to alleviate sufferance from X-ray over attenuation in large biological samples. Hearts were extracted from healthy pigs (N = 2), and sheep (N = 2) with either induced chronic myocardial infarction and fibrotic scar formation or induced chronic atrial fibrillation. Excised hearts were perfused with: a saline solution supplemented with a calcium ion quenching agent and a vasodilator, ethanol in serial dehydration, and hexamethyldisilizane under vacuum. The latter reinforced the heart structure during air-drying for 1 week. Collagen-dominant tissue was selectively bound by an X-ray contrast-enhancing agent, phosphomolybdic acid. Tissue conformation was stable in air, permitting long-duration microcomputed tomography acquisitions to obtain high-resolution (isotropic 20.7 &#181;m) images. Optimal contrast agent loading by diffusion showed selective contrast enhancement of the epithelial layer and sub-endocardial Purkinje fibers in healthy pig ventricles. Atrial fibrillation (AF) hearts showed enhanced contrast accumulation in the posterior walls and appendages of the atria, attributed to greater collagen content. Myocardial infarction hearts showed increased contrast selectively in regions of cardiac fibrosis, which enabled the identification of interweaving surviving myocardial muscle fibers. Contrast-enhanced air-dried tissue preparations enabled microscale imaging of the intact large mammalian heart and selective contrast enhancement of underlying disease constituents.

Here, we present a protocol to obtain high resolution micro computed tomography images of healthy and pathological large mammalian whole hearts with collagen-selective contrast enhancement.

用于慢性病大型哺乳动物心脏模型对比增强显影显微计算机断层扫描的组织制备技术

Structural remodeling is a common consequence of chronic pathological stresses imposed on the heart. Understanding the architectural and compositional ...

Scanning Electron Microscopy of Macerated Tissue to Visualize the Extracellular Matrix

Fibrosis is a component of all forms of heart disease regardless of etiology, and while much progress has been made in the field of cardiac matrix biology, there are still major gaps related to how the matrix is formed, how physiological and pathological remodeling differ, and most importantly how matrix dynamics might be manipulated to promote healing and inhibit fibrosis. There is currently no treatment option for controlling, preventing, or reversing cardiac fibrosis. Part of the reason is likely the sheer complexity of cardiac scar formation, such as occurs after myocardial infarction to immediately replace dead or dying cardiomyocytes. The extracellular matrix itself participates in remodeling by activating resident cells and also by helping to guide infiltrating cells to the defunct lesion. The matrix is also a storage locker of sorts for matricellular proteins that are crucial to normal matrix turnover, as well as fibrotic signaling. The matrix has additionally been demonstrated to play an electromechanical role in cardiac tissue. Most techniques for assessing fibrosis are not qualitative in nature, but rather provide quantitative results that are useful for comparing two groups but that do not provide information related to the underlying matrix structure. Highlighted here is a technique for visualizing cardiac matrix ultrastructure. Scanning electron microscopy of decellularized heart tissue reveals striking differences in structure that might otherwise be missed using traditional quantitative research methods.

Shown here is a method for visualizing extracellular matrix ultrastructure in decellularized cardiac tissues.

扫描浸软组织的电子显微镜可视化的细胞外基质

Fibrosis is a component of all forms of heart disease regardless of etiology, and while much progress has been made in the field of cardiac matrix ...

生物学

Ultrasound-Guided Induced Pluripotent Stem Cell-Derived Cardiomyocyte Implantation in Myocardial Infarcted Mice

The key objective of cell therapy after myocardial infarction (MI) is to effectively enhance the cell grafted rate, and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) are a promising cell source for cardiac repair after ischemic damage. However, a low grafted rate is a significant obstacle for effective cardiac tissue regeneration after transplantation. This protocol shows that multiple hiPSC-CM ultrasound-guided percutaneous injections into an MI area effectively increase cell transplantation rates. The study also describes the entire hiPSC-CM culture process, pretreatment, and ultrasound-guided percutaneous delivery methods. In addition, the use of human mitochondrial DNA help detect the absence of hiPSC-CMs in other mouse organs. Lastly, this paper describes the changes in cardiac function, angiogenesis, cell size, and apoptosis at the infarcted border zone in mice 4 weeks after cell delivery. It can be concluded that echocardiography-guided percutaneous injection of the left ventricular myocardium is a feasible, relatively invasive, satisfactory, repeatable, and effective cellular therapy.

Ultrasound-guided cell delivery around the site of myocardial infarction in mice is a safe, effective, and convenient way of cell transplantation.

超声引导诱导多能干细胞来源心肌细胞植入心肌梗死小鼠

The key objective of cell therapy after myocardial infarction (MI) is to effectively enhance the cell grafted rate, and human induced pluripotent stem ...

An Experimental Model of Myocardial Infarction for Studying Cardiac Repair and Remodeling in Knockout Mice

Cardiovascular disease is the most prevalent cause of death in Western countries, with acute myocardial infarction (MI) being the most prevalent form. This paper describes a protocol for studying the role of galectin 3 (Gal-3) in the temporal evolution of cardiac healing and remodeling in an experimental animal model of MI. 
The procedures described include an experimental model of MI with a permanent coronary ligature in male C57BL/6J (control) and Gal-3 knockout (KO) mice, an echocardiography procedure to study cardiac remodeling and systolic function in vivo, a histological evaluation of interstitial myocardial fibrosis with picrosirius red-stained and rhodamine-conjugated lectin-stained sections for studying myocyte hypertrophy by the cross-sectional area (MCSA), and the quantification of infarct size and cardiac remodeling (scar thinning, septum thickness, and expansion index) by planimetry in slices stained with Masson's trichrome and triphenyl tetrazolium chloride. Gal-3 KO mice with MI showed disrupted cardiac remodeling and an increase in the scar thinning ratio and the expansion index. At the onset of MI, myocardial function and cardiac remodeling were also severely affected. At 4 weeks post MI, the natural evolution of fibrosis in infarcted Gal-3 KO mice was also affected. 
In summary, the experimental model of MI is a suitable model for studying the temporal evolution of cardiac repair and remodeling in mice with the genetic deletion of Gal-3 and other animal models. The lack of Gal-3 affects the dynamics of cardiac repair and disrupts the evolution of cardiac remodeling and function after MI.

Here, we describe an experimental model of myocardial infarction, an echocardiography procedure to study cardiac remodeling and function, and procedures for quantifying fibrosis and hypertrophy in picrosirius red-stained and rhodamine-stained sections, as well as the infarct size and expansion index in slices stained with Masson's trichrome.

Cardiovascular disease is the most prevalent cause of death in Western countries, with acute myocardial infarction (MI) being the most prevalent form. ...

揭示小鼠肺静脉心肌结构

Microdissection and Immunofluorescence Staining of Myocardial Sleeves in Murine Pulmonary Veins

Pulmonary veins (PVs) are the major source of ectopic beats in atrial arrhythmias and play a crucial role in the development and progression of atrial fibrillation (AF). PVs contain myocardial sleeves (MS) composed of cardiomyocytes. MS are implicated in the initiation and maintenance of AF, as they preserve similarities to the cardiac working myocardium, including the ability to generate ectopic electrical impulses. Rodents are widely used and may represent excellent animal models to study the pulmonary vein myocardium since cardiomyocytes are widely present all over the vessel wall. However, precise microdissection and preparation of murine PVs is challenging due to the small organ size and intricate anatomy.
We demonstrate a microscopy-guided microdissection protocol for isolating the murine left atrium (LA) together with the PVs. Immunofluorescence staining using cardiac Troponin-T (cTNT) and connexin 43 (Cx43) antibodies is performed to visualize the LA and PVs in full length. Imaging at 10x and 40x magnification provides a comprehensive view of the PV structure as well as detailed insights into the myocardial architecture, particularly highlighting the presence of connexin 43 within the MS.

作者聚焦：开发跨物种心房颤动研究的转化模型 

This protocol demonstrates microscopy-guided isolation and immunofluorescence staining of murine pulmonary veins. We prepare tissue samples containing the left atrium, pulmonary veins, and the corresponding lungs and stain them for cardiac Troponin T and Connexin 43.

小鼠肺静脉心肌套的显微解剖和免疫荧光染色

Pulmonary veins (PVs) are the major source of ectopic beats in atrial arrhythmias and play a crucial role in the development and progression of atrial ...

可视化

摘要

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此视频中的章节

通过轻型显微镜对小鼠急性心肌炎模型中白细胞浸润的定量可视化

在健康和受伤的老鼠心脏中为三维纤维细胞组织进行精炼的清晰组织清除

完整的心包缺血性啮齿动物模型

用于慢性病大型哺乳动物心脏模型对比增强显影显微计算机断层扫描的组织制备技术

扫描浸软组织的电子显微镜可视化的细胞外基质

超声引导诱导多能干细胞来源心肌细胞植入心肌梗死小鼠

An Experimental Model of Myocardial Infarction for Studying Cardiac Repair and Remodeling in Knockout Mice

小鼠肺静脉心肌套的显微解剖和免疫荧光染色

小鼠肺静脉心肌套的显微解剖和免疫荧光染色

小鼠肺静脉心肌套的显微解剖和免疫荧光染色