这项工作是支持汉密尔顿 - 费尔利NHMRC奖学金（RH，AL），维多利亚州政府的运营基础设施支援计划（RH，EW）和的玛丽·居里INDUSTRIA学术界的伙伴关系和途径补助，赞助由欧盟委员会（PD ME） 。笔者想感谢博士弗朗西斯安德烈博士Miyague，俄，罗西塔Kinnart女士和伊万先生Laermans的为他们的技术专长，在生产这种视频。

下面的实验动物伦理委员会，天主教鲁汶大学，比利时鲁汶协议批准。我们跟着前面描述的手术过程13，包括一些方法上的变化，尤其是在麻醉过程。 1。诱导胎儿宫内发育迟缓（IUGR） <ol><li>于孕兔（混合登德尔蒙德和新西兰白）的时间被安置在个别网箱12/12小时光照时间表与水和标准兔饲料自由采食 ，从胎龄（GA）18天的访问。 GA 25天（足月约是31天），兔子被转移到手术室手术造成胎儿宫内发育迟缓。手术前，随机分配一个“案例”（胎儿宫内发育迟缓）和“控制”子宫角子宫双角的兔子，用随机软件（GraphPad软件，USA）19。功率计算样本大小应由个别ŗesearchers他们感兴趣的问题。 </li><li> 麻醉过程。 是通过诱导麻醉管理氯胺酮35毫克/公斤（CEVA SANTE ANIMALE，布鲁塞尔，比利时）和甲苯噻嗪5毫克/公斤（CEVA SANTE ANIMALE，布鲁塞尔，比利时）的肌注后腿。然后保持1-4％的 ​​混合吸入麻醉异氟醚（Isoba兽医;雅培制药有限公司Queenborough，肯特，英国O 2的2升/分钟）。将脉搏血氧仪（N-20的Nellcor，Covidien公司，爱尔兰）对产妇的第二个和第三个脚趾连续监测心脏率和动脉氧饱和度。 </li><li> 外科手术。 <ol><li> 术前用药，手术开始之前，管理预防性应用抗生素青霉素G，30万IU（克拉制药，HOOGSTRATEN，比利时），子宫宫缩醋酸甲羟孕酮0.9毫克/千克（德波-孕酮，法玛西亚厄普约翰，Puurs位于比利时）和镇痛丁丙诺啡0.03毫克/公斤（Temgesic先灵葆雅）皮下注射2.5毫升注射器在一个单一的。 </li><li> 兔准备。变暖垫手术的持续时间将兔子。将头发从腹部外科领域应用防腐剂7.5％碘伏（聚维酮碘，普渡大学，康涅狄格州，美国）。一个完整的无菌协议。 </li><li> 腹部剖腹探查术。渗透切口部位皮下局部麻醉（2毫升1％的利多卡因，B布劳恩医疗，比利时）。切口部位应该是在中线的长度约5厘米，在下部2/3的腹部。皮肤一旦被打开，使用尖锐，钝性分离的混合物，至腹直肌鞘暴露。必须小心，以避免血管产妇乳腺位于任一侧的条目（ 图1A）上的中线。抓住腹直肌鞘和腹膜，帐篷，以防止意外的腹腔内容列入，并准确输入使用锐性剥离（ 图1B）。 </li><li> 子宫外置环绕外科领域，用纱布浸泡在温暖的盐水窗帘。小心把握和exteriorize两侧双角子宫。必须小心，不要放置下的每个子宫角阴道或卵巢年底的紧张，因为这可能导致不受欢迎的出血，疼痛和子宫收缩。助理不断灌溉露出温暖的盐水，以防止子宫收缩子宫。触诊和记录胎儿存在于每个喇叭的数量。按照惯例，胎儿卵巢端指定的第一个胎儿。子宫角之一的情况下喇叭，另一种是控制角。胎儿宫内发育迟缓感应识别先前随机分配的情况下，喇叭，然后，更换控制反击号角内部控制胎儿腹部（）。 </li><li> 手术引起的胎儿宫内发育迟缓 。子宫胎盘血管识别每个孕囊在指定的情况下，喇叭（ 图1C）。手术结扎这些船只使用5-0 polyglacin线（薇乔爱惜康，强生医疗，USA）（ 图1D-1E）的40-50％。在实践中，常常有三个维管束提供每个孕囊。在这种情况下，最大的维管束结扎。一旦完成，子宫再次灌溉用温热盐水并小心地返回到腹部。 </li><li> 腹部闭合。关闭腹部两层，采用连续运行2-0 polyglacin线（薇乔爱惜康，强生医疗，美国）。关闭皮肤的polyglactin缝合皮下3-0（薇乔，爱惜，美国强生公司医疗）。喷铝气溶胶在伤口上，以防止兔从购买干扰缝线。 </li><li> 恢复停止麻醉，并密切观察呼吸恢复。兔子，然后收纳如上所述的食物和水随意访问，每天观察。 </li></ol></li></ol> 2。进行胎儿超声心动图和多普勒超声脉冲波<ol><li>同样的兔子，然后转移GA 30天，超声心动图和超声评价。变暖的垫被放置在兔的持续时间的检查。 </li><li> 麻醉过程。 <ol><li>是通过诱导麻醉管理氯胺酮35毫克/公斤（CEVA SANTE ANIMALE，布鲁塞尔，比利时）和甲苯噻嗪5毫克/千克（CEVA SANTE ANIMALE，布鲁塞尔，比利时）的肌注。一旦稳重，取得静脉通道，使用24号外围耳静脉插入套管（BD因西特-W，碧迪输液治疗系统，犹他州，美国）。 </li><li>维持麻醉用氯胺酮和甲苯噻嗪连续输注：2毫升氯胺酮（100毫克/毫升）和1.5毫升甲苯噻嗪（20毫克/毫升），46.5 ml生理盐水，然后通过注射器泵输注在40毫升/小时。三路抽头固定和连接5毫升注射器抢救麻醉2毫升的氯胺酮（100毫克/毫升）和1.5毫升甲苯噻嗪（20毫克/毫升）。很少需要的0.5毫升麻醉救援的丸药。管理镇痛丁丙诺啡0.03毫克/千克（Temgesic先灵葆雅）subcutaneouslyprior手术。应用面罩氧气2升/分钟。将脉搏血氧仪（N-20的Nellcor，Covidien公司，爱尔兰）对产妇的第二个和第三个脚趾连续监测心脏率和动脉氧饱和度。 </li></ol></li><li> 腹部剖腹探查术及子宫表面化。参见1.3.3和1.3.4。 </li><li> 胎儿超声心动图和超声检查定位。 <ol><li>将兔的横向位置朝向研究者。这便于检索一个单一的检查孕囊和子宫胎盘血管防止过度牵拉。尽可能以尽量减少暴露时间，尽量exteriorize只有一个孕囊。确保暴露的孕囊放在纱布灌溉温暖的盐水。中使用的超声检查，以确保在不同的研究组，一般只有在卵巢癌和阴道的每个子宫角的两端胎儿之间的标准化结果的。 </li><li>胎儿心脏功能是很容易受到到子宫外化的效果，改变在胎盘血管从超声波换能器的温度和压力。为了最大限度地减少这些环境和医源性混杂对心脏功能的影响，超声检查必须立即开始表面化后孕囊，应该是系统的，高效的。根据我们的经验，在胎儿心脏功能的变化很少发生在第5分钟的曝光。如果遇到胎儿心动过缓，取出超声探头，重新胎儿，防止胎儿胎盘血管扭结，灌溉用盐水或短暂回暖返回孕囊进入母体腹部。如果胎儿心动过缓是持久性的，检查此FETUS应该放弃赞成检查下胎儿。 </li></ol></li><li> 胎儿超声心动图检查。 <ol><li> VEVO Visualsonics 2100（多伦多，加拿大）的高分辨率microultrasound平台与心脏和应变分析软件的安装是必需的。 MS-250àVisualSonics的换能器（加拿大多伦多VisualSonics）是用于数据采集。这有13-24 MHz的带宽的中心频率为21兆赫。的几何焦点的最大图像宽度是15毫米，23毫米和图像的最大深度为30mm。足迹是28×5.75毫米。按照美国社会的超声心动图的指引和标准采集数据20胎儿超声心动图的性能。 </li><li> 数据采集1的侧视图。在横向视图四腔的电平，记录至少5个心动周期的B模式电影回放，以确定应变，应变率，速度和位移。这是离线分析使用VevoStrain然后，可以（Visualsonics，多伦多，加拿大）算法21 M型超声心动图指标如前所述，在杂志上的细节。这个标准视图中获得。离线测量心脏结构和功能，然后可以分析：内部心室和室间隔直径在收缩和舒张，卷，每搏输出量，短轴缩短率，射血分数和心输出量21 </li><li> 数据采集2：根尖视图。水平的心尖四腔视图中，B模式电影回放可以重复为如上所述的VevoStrain分析。 M型超声心动图是用来评估三尖瓣和二尖瓣环平面收缩漂移（MAPSE）和纵向应变和应变率（TAPSE）22,23心尖视图还允许评估瓣膜血流速度波形和修改后的心肌性能指标如先前描述24 </li></ol></li><li> 胎儿胎盘脉冲多普勒ULT挥手rasound。 </li></ol>流速波形（FVW）是通过脐部血管彩色多普勒定位，然后将脉冲多普勒取样门上免费循环脐带脐动脉25脐动脉，大脑中动脉（MCA）FVW位于Willis环是由位于彩色多普勒后，将脉冲多普勒取样门刚刚超越马华的起源。26静脉导管（DV）是通过将脉冲多普勒取样门近端部分的DV看到FVW彩色多普勒，它起源从肝内脐静脉在矢状或横向视图的胎儿。26搏动指数（PI），离线计算的的心血管VisualSonics分析软件。

笔者扬德虎格教授有一个研究协议，VisualSonics的。的其余没有披露。

我们已经使用了一个验证的方法，手术子宫胎盘血流量减少，产生胎儿宫内发育迟缓13-16兔子，后来检查胎儿心脏功能14描述microultrasound的技术和可用在VEVO VisualSonics 2100心脏功能分析。繁殖能力，人类胎儿宫内发育迟缓胎儿胎儿胎盘多普勒变化中的小动物模型，然后让最近描述的超声心动图检查心脏功能是胎儿心脏研究可能取得进展，在临床相关的方式。 小?...

心血管疾病负担，导致胎儿宫内发育迟缓（IUGR）不能被夸大。它是导致死胎，先天性畸形后1胎儿宫内发育迟缓是指对胎儿未能达到其增长潜力，通常是一个导致胎盘功能不全。2在幸存者中，心肌功能障碍明显的心血管健康状况不佳是显而易见的整个生命跨度在婴儿期和童年3,4和后续的高血压，糖尿病6，肥胖在成年生活中发展-从出生的所有累积的心脏危险因素对缺血性心脏疾病过早死亡7 发展动物模型的特点，建立胎儿宫内发育迟缓和胎儿的后续反应减少基板的可用性母胎通信是必要的，如果我们双方更好地了解胎儿宫内发育迟缓有关汽车的病理生理DIAC减值和心脏保护策略，以提高胎儿和出生后的健康发展。在这方面，许多不同的模式，不同的植物物种已被描述。8胎儿宫内发育迟缓通常产妇营养不足引起低蛋白饮食在啮齿类动物中，9手术切除或结扎子宫血流量在啮齿类动物和豚鼠10或闭塞脐动脉的羊。11然而，很明显，没有模型充分概括了人类胎儿宫内发育迟缓。 在当前的方法论研究，我们采用了很好的验证方法选择性子宫胎盘血管中断，不仅产生超声观察胎儿的心血管反应，临床上14，但也允许审讯胎儿心脏功能新颖的超声心动图使用microultrasound技术在兔13-16的VEVO VisualSonics 2100。虽然多普勒超声fetopl保持acental血管的基石，目前的产前监测胎儿宫内发育迟缓胎儿17，超声心动图功能正在越来越多地被用于疾病的病理生理机制提供新的见解，并以评估胎儿健康18因此，在这里我们采取这些进步从临床研究和描述的动物模型，港口不仅成像的复杂性，但也提供了实验平台调查机制的途径和新的疗法。

<table border="1">
	<tbody>
 <tr>
 <td>Name of Reagent/Material</td>
 <td>Company</td>
 <td>Catalog Number</td>
 <td>Comments</td>
 </tr>
 <tr>
 <td>Ketamine</td>
 <td>Ceva Sante Animale</td>
 <td></td>
 <td><a href="http://www.ceva.com/en" target="_blank">http://www.ceva.com/en</a></td>
 </tr>
 <tr>
 <td>Xylazine</td>
 <td>Ceva Sante Animale</td>
 <td></td>
 <td><a href="http://www.ceva.com/en" target="_blank">http://www.ceva.com/en</a></td>
 </tr>
 <tr>
 <td>Depot Provera</td>
 <td>Pharmacia Upjohn</td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Penicillin G</td>
 <td>Kela Pharma</td>
 <td></td>
 <td><a href="http://www.kela.be" target="_blank">http://www.kela.be</a></td>
 </tr>
 <tr>
 <td >Lidocaine</td>
 <td>B Braun Medical</td>
 <td></td>
 <td><a href="http://www.bbraun.com/" target="_blank">http://www.bbraun.com/</a></td>
 </tr>
 <tr>
 <td>Temgesic</td>
 <td>Schering-Plough</td>
 <td></td>
 <td><a href="http://www.merck-animal-health-usa.com/" target="_blank">http://www.merck-animal-health-usa.com/</a></td>
 </tr>
 <tr>
 <td>Isolurane</td>
 <td>Isoba Vet; Abbott Laboratories Ltd</td>
 <td></td>
 <td><a href="http://www.abbottanimalhealth.com/index.html" target="_blank">http://www.abbottanimalhealth.com/index.html</a></td>
 </tr>
 <tr>
 <td>Ethicon</td>
 <td>Johnson and Johnson</td>
 <td></td>
 <td><a href="http://www.ethiconproducts.co.uk/products/sutures" target="_blank">http://www.ethiconproducts.co.uk/products/sutures</a></td>
 </tr>
 <tr>
 <td>Ethicon</td>
 <td>Johnson and Johnson</td>
 <td></td>
 <td><a href="http://www.ethiconproducts.co.uk/products/sutures" target="_blank">http://www.ethiconproducts.co.uk/products/sutures</a></td>
 </tr>
 <tr>
 <td>Ethicon</td>
 <td>Johnson and Johnson</td>
 <td></td>
 <td><a href="http://www.ethiconproducts.co.uk/products/sutures" target="_blank">http://www.ethiconproducts.co.uk/products/sutures</a></td>
 </tr>
 <tr>
 <td>VEVO 2100</td>
 <td>VisualSonics</td>
 <td>SN100-0032</td>
 <td><a href="http://www.visualsonics.com/" target="_blank">http://www.visualsonics.com/</a></td>
 </tr>
 <tr>
 <td>Aquasonic Gel</td>
 <td>Parker Laboratories</td>
 <td>01 02</td>
 <td><a href="http://www.parkerlabs.com/ultrasound_products.html" target="_blank">http://www.parkerlabs.com/ultrasound_products.html</a></td>
 </tr>
 <tr>
 <td>Nellcor N-20PA Pulse oximeter</td>
 <td>Covidien</td>
 <td></td>
 <td><a href="http://www.nellcor.com/prod/PRODUCT.ASPX?S1=POX&amp;S2=MON&amp;id=282&amp;V" target="_blank">http://www.nellcor.com/prod/PRODUCT.ASPX?S1=POX&amp;S2=MON&amp;id=282&amp;V</a></td>
 </tr>
	 </tbody>
 </table>

fetal echocardiography and pulsed-wave doppler ultrasound in a rabbit model of intrauterine growth restriction

胎儿宫内发育迟缓（IUGR）导致心功能异常，这是明显的产前由于胎儿胎盘多普勒超声及胎儿超声心动图的进步。越来越多，这些成像方式被雇用临床检查心脏功能，并在子宫内健康评估，从而指导出生决策时机。在这里，我们使用的胎儿宫内发育迟缓，让兔子模型分析心脏功能的临床相关的方式。使用异氟醚诱导麻醉，胎儿宫内发育迟缓手术创造胎龄25天进行剖腹探查，露出双角子宫，然后结扎每个孕囊在一个单一的子宫角子宫胎盘血管供应的40-50％。在兔双角子宫的其他角作为内部控制胎儿。然后，在胎龄30天（足月）恢复后，同一只兔子进行检查胎儿心脏功能。麻醉诱导与吉胆INE和甲苯噻嗪肌肉注射，然后保持连续静脉滴注氯胺酮和甲苯噻嗪对胎儿的心脏功能，以尽量减少医源性影响。重复剖腹探查进行揭露每个孕囊及胎儿心脏功能的一个microultrasound考试（VEVO VisualSonics 2100）进行。胎盘功能不全是由凸起的搏动指数或缺席或逆转的舒张末期脐动脉多普勒波形流可见一斑。静脉导管和大脑中动脉多普勒检查。胎儿超声心动图检查进行记录B模式，M模式和流速波形在横向和心尖意见。离线计算确定标准的M型心脏变量，三尖瓣和二尖瓣环平面收缩漂移，斑点追踪应变分析，修改后的心肌性能指数和血管血流速度波形的利益。这个小动物模型，胎儿宫内发育迟缓，因此能提供在电脑上检查Ø心脏功能与目前的临床实践是一致的，因此可用于转化研究设置。

一个不对称的生长受限制的子宫胎盘血管结扎的胎儿和胎盘从较正常对照图1F中的胎儿和胎盘。不对称增长证实了减少新生儿出生体重和头围增大：腹围比对照组。从胎儿胎盘多普勒研究的代表性结果示于图2。正端控制胎儿舒张期血流显示一个正常的低电阻模式。随着逐步增加阻力见于胎盘在胎儿宫内发育迟缓的胎儿，没有，然后逆转舒张末流是显而易见的。 图3</...

Watch this Scientific Journal Video about Fetal Echocardiography and Pulsed-wave Doppler Ultrasound in a Rabbit Model of Intrauterine Growth Restriction at JoVE.com

Fetal Echocardiography and Pulsed-wave Doppler Ultrasound in a Rabbit Model of Intrauterine Growth Restriction

我们描述检查胎儿心脏功能与现代功能的胎儿超声心动图和使用VisualSonics VEVO 2100 microultrasound的胎儿胎盘多普勒超声在手术引起的胎儿宫内生长受限模型兔子。

在家兔模型宫内生长受限胎儿超声心动图和多普勒超声脉冲波

Fetal intrauterine growth restriction (IUGR) results in abnormal cardiac function that is apparent antenatally due to advances in fetoplacental Doppler ...

fetal-echocardiography-pulsed-wave-doppler-ultrasound-rabbit-model

Research

JoVE Journal

Medicine

28.1K 次观看.  University Hospitals Leuven. 我们描述检查胎儿心脏功能与现代功能的胎儿超声心动图和使用VisualSonics VEVO 2100 microultrasound的胎儿胎盘多普勒超声在手术引起的胎儿宫内生长受限模型兔子。

视频: Fetal Echocardiography and Pulsed-wave Doppler Ultrasound in a Rabbit Model of Intrauterine Growth Restriction

Murine Echocardiography and Ultrasound Imaging

Rodent models of cardiac pathophysiology represent a valuable research tool to investigate mechanism of disease as well as test new therapeutics.1 Echocardiography provides a powerful, non-invasive tool to serially assess cardiac morphometry and function in a living animal.2 However, using this technique on mice poses unique challenges owing to the small size and rapid heart rate of these animals.3 Until recently, few ultrasound systems were capable of performing quality echocardiography on mice, and those generally lacked the image resolution and frame rate necessary to obtain truly quantitative measurements. Newly released systems such as the VisualSonics Vevo2100 provide new tools for researchers to carefully and non-invasively investigate cardiac function in mice. This system generates high resolution images and provides analysis capabilities similar to those used with human patients. Although color Doppler has been available for over 30 years in humans, this valuable technology has only recently been possible in rodent ultrasound.4,5 Color Doppler has broad applications for echocardiography, including the ability to quickly assess flow directionality in vessels and through valves, and to rapidly identify valve regurgitation. Strain analysis is a critical advance that is utilized to quantitatively measure regional myocardial function.6 This technique has the potential to detect changes in pathology, or resolution of pathology, earlier than conventional techniques. Coupled with the addition of three-dimensional image reconstruction, volumetric assessment of whole-organs is possible, including visualization and assessment of cardiac and vascular structures. Murine-compatible contrast imaging can also allow for volumetric measurements and tissue perfusion assessment.

This video demonstrates use of a rail-mounted high-frequency ultrasound probe to perform echocardiography on an anesthetized mouse. The methods describe both conventional two-dimensional and M-mode measurements of cardiac function in addition to newer, more powerful tools such as color Doppler, strain analysis, as well as general and targeted contrast imaging.

小鼠超声心动图和超声成像

Rodent models of cardiac pathophysiology represent a valuable research tool to investigate mechanism of disease as well as test new therapeutics.1  ...

科研

医学

Assessing Teratogenic Changes in a Zebrafish Model of Fetal Alcohol Exposure

Fetal alcohol syndrome (FAS) is a severe manifestation of embryonic exposure to ethanol. It presents with characteristic defects to the face and organs, including mental retardation due to disordered and damaged brain development. Fetal alcohol spectrum disorder (FASD) is a term used to cover a continuum of birth defects that occur due to maternal alcohol consumption, and occurs in approximately 4% of children born in the United States. With 50% of child-bearing age women reporting consumption of alcohol, and half of all pregnancies being unplanned, unintentional exposure is a continuing issue2. In order to best understand the damage produced by ethanol, plus produce a model with which to test potential interventions, we developed a model of developmental ethanol exposure using the zebrafish embryo. Zebrafish are ideal for this kind of teratogen study3-8. Each pair lays hundreds of eggs, which can then be collected without harming the adult fish. The zebrafish embryo is transparent and can be readily imaged with any number of stains. Analysis of these embryos after exposure to ethanol at different doses and times of duration and application shows that the gross developmental defects produced by ethanol are consistent with the human birth defect. Described here are the basic techniques used to study and manipulate the zebrafish FAS model.

In order to understand the molecular mechanisms of the ethanol-induced developmental damage, we have developed a zebrafish model of ethanol exposure and are exploring the physical, cellular, and genetic alterations that occur after ethanol exposure1. We then seek to find potential interventions and rapidly test them in this animal model.

在斑马鱼模型的胎儿酒精暴露评估致畸的变化

Fetal alcohol syndrome (FAS) is a severe manifestation of embryonic exposure to ethanol. It presents with characteristic defects to the face and organs, ...

A Novel Surgical Approach for Intratracheal Administration of Bioactive Agents in a Fetal Mouse Model

Prenatal pulmonary delivery of cells, genes or pharmacologic agents could provide the basis for new therapeutic strategies for a variety of genetic and acquired diseases. Apart from congenital or inherited abnormalities with the requirement for long-term expression of the delivered gene, several non-inherited perinatal conditions, where short-term gene expression or pharmacological intervention is sufficient to achieve therapeutic effects, are considered as potential future indications for this kind of approach. Candidate diseases for the application of short-term prenatal therapy could be the transient neonatal deficiency of surfactant protein B causing neonatal respiratory distress syndrome1,2 or hyperoxic injuries of the neonatal lung3. Candidate diseases for permanent therapeutic correction are Cystic Fibrosis (CF)4, genetic variants of surfactant deficiencies5 and &alpha;1-antitrypsin deficiency6.
Generally, an important advantage of prenatal gene therapy is the ability to start therapeutic intervention early in development, at or even prior to clinical manifestations in the patient, thus preventing irreparable damage to the individual. In addition, fetal organs have an increased cell proliferation rate as compared to adult organs, which could allow a more efficient gene or stem cell transfer into the fetus. Furthermore, in utero gene delivery is performed when the individual's immune system is not completely mature. Therefore, transplantation of heterologous cells or supplementation of a non-functional or absent protein with a correct version should not cause immune sensitization to the cell, vector or transgene product, which has recently been proven to be the case with both cellular and genetic therapies7.
In the present study, we investigated the potential to directly target the fetal trachea in a mouse model. This procedure is in use in larger animal models such as rabbits and sheep8, and even in a clinical setting9, but has to date not been performed before in a mouse model. When studying the potential of fetal gene therapy for genetic diseases such as CF, the mouse model is very useful as a first proof-of-concept because of the wide availability of different transgenic mouse strains, the well documented embryogenesis and fetal development, less stringent ethical regulations, short gestation and the large litter size.
Different access routes have been described to target the fetal rodent lung, including intra-amniotic injection10-12, (ultrasound-guided) intrapulmonary injection13,14 and intravenous administration into the yolk sac vessels15,16 or umbilical vein17. Our novel surgical procedure enables researchers to inject the agent of choice directly into the fetal mouse trachea which allows for a more efficient delivery to the airways than existing techniques18.

We developed a novel surgical approach for intratracheal administration of bioactive agents into the mouse fetus. The delivery route is more efficient in targeting the fetal mouse lungs than the commonly used intra-amniotic injection. This procedure has to date not been described in a mouse model.

一种新的手术方法气管内注射生物活性剂在胎鼠模型

Prenatal pulmonary delivery of cells, genes or pharmacologic agents could provide the basis for new therapeutic strategies for a variety of genetic and ...

Murine Fetal Echocardiography

Transgenic mice displaying abnormalities in cardiac development and function represent a powerful tool for the understanding the molecular mechanisms underlying both normal cardiovascular function and the pathophysiological basis of human cardiovascular disease. Fetal and perinatal death is a common feature when studying genetic alterations affecting cardiac development 1-3. In order to study the role of genetic or pharmacologic alterations in the early development of cardiac function, ultrasound imaging of the live fetus has become an important tool for early recognition of abnormalities and longitudinal follow-up. Noninvasive ultrasound imaging is an ideal method for detecting and studying congenital malformations and the impact on cardiac function prior to death 4. It allows early recognition of abnormalities in the living fetus and the progression of disease can be followed in utero with longitudinal studies 5,6. Until recently, imaging of fetal mouse hearts frequently involved invasive methods. The fetus had to be sacrificed to perform magnetic resonance microscopy and electron microscopy or surgically delivered for transillumination microscopy. An application of high-frequency probes with conventional 2-D and pulsed-wave Doppler imaging has been shown to provide measurements of cardiac contraction and heart rates during embryonic development with databases of normal developmental changes now available 6-10. M-mode imaging further provides important functional data, although, the proper imaging planes are often difficult to obtain. High-frequency ultrasound imaging of the fetus has improved 2-D resolution and can provide excellent information on the early development of cardiac structures 11.

Fetal and perinatal death is a common feature when studying genetic alterations affecting cardiac development. High-frequency ultrasound imaging has improved 2-D resolution and can provide excellent information on early cardiac development and is an ideal method to detect the impact on cardiac structure and function prior to death.

小鼠胎儿超声心动图

Transgenic mice displaying abnormalities in  cardiac development and function represent a powerful tool for the understanding  the molecular mechanisms ...

A Mouse Fetal Skin Model of Scarless Wound Repair

Early in utero, but not in postnatal life, cutaneous wounds undergo regeneration and heal without formation of a scar. Scarless fetal wound healing occurs across species but is age dependent. The transition from a scarless to scarring phenotype occurs in the third trimester of pregnancy in humans and around embryonic day 18 (E18) in mice. However, this varies with the size of the wound with larger defects generating a scar at an earlier gestational age. The emergence of lineage tracing and other genetic tools in the mouse has opened promising new avenues for investigation of fetal scarless wound healing. However, given the inherently high rates of morbidity and premature uterine contraction associated with fetal surgery, investigations of fetal scarless wound healing in vivo require a precise and reproducible surgical model. Here we detail a reliable model of fetal scarless wound healing in the dorsum of E16.5 (scarless) and E18.5 (scarring) mouse embryos.

During mammalian development, early gestational skin wounds heal without a scar. Here we detail a reliable and reproducible model of fetal scarless wound healing in the cutaneous dorsum of E16.5 (scarless) and E18.5 (scarring) mouse embryos.

对无瘢痕修复鼠标胎儿皮肤模型

Early in utero, but not in postnatal life, cutaneous wounds undergo regeneration and heal without formation of a scar. Scarless fetal wound healing occurs ...

Intrauterine Telemetry to Measure Mouse Contractile Pressure In Vivo

A complex integration of molecular and electrical signals is needed to transform a quiescent uterus into a contractile organ at the end of pregnancy. Despite the discovery of key regulators of uterine contractility, this process is still not fully understood. Transgenic mice provide an ideal model in which to study parturition. Previously, the only method to study uterine contractility in the mouse was ex vivo isometric tension recordings, which are suboptimal for several reasons. The uterus must be removed from its physiological environment, a limited time course of investigation is possible, and the mice must be sacrificed. The recent development of radiometric telemetry has allowed for longitudinal, real-time measurements of in vivo intrauterine pressure in mice. Here, the implantation of an intrauterine telemeter to measure pressure changes in the mouse uterus from mid-pregnancy until delivery is described. By comparing differences in pressures between wild type and transgenic mice, the physiological impact of a gene of interest can be elucidated. This technique should expedite the development of therapeutics used to treat myometrial disorders during pregnancy, including preterm labor.

Intrauterine Telemetry to Measure Mouse Contractile Pressure In Vivo

This manuscript provides a protocol for implanting telemeters in the mouse for the purpose of measuring intrauterine pressures during pregnancy.

宫内遥测来衡量鼠标收缩压力<em&gt;在体内</em

A complex integration of molecular and electrical signals is needed to transform a quiescent uterus into a contractile organ at the end of pregnancy. ...

Percutaneous Contrast Echocardiography-guided Intramyocardial Injection and Cell Delivery in a Large Preclinical Model

Cell and gene therapy are exciting and promising strategies for the purpose of cardiac regeneration in the setting of heart failure with reduced ejection fraction (HFrEF). Before they can be considered for use, and implemented in humans, extensive preclinical studies are required in large animal models to evaluate the safety, efficacy, and fate of the injectate (e.g., stem cells) once delivered into the myocardium. Small rodent models offer advantages (e.g., cost effectiveness, amenability for genetic manipulation); however, given inherent limitations of these models, the findings in these rarely translate into the clinic. Conversely, large animal models such as rabbits, have advantages (e.g., similar cardiac electrophysiology compared to humans and other large animals), whilst retaining a good cost-effective balance. Here, we demonstrate how to perform a percutaneous contrast echocardiography-guided intramyocardial injection (IMI) technique, which is minimally invasive, safe, well tolerated, and very effective in the targeted delivery of injectates, including cells, into several locations within the myocardium of a rabbit model. For the implementation of this technique, we also have taken advantage of a widely available clinical echocardiography system. After putting in practice the protocol described here, a researcher with basic ultrasound knowledge will become competent in the performance of this versatile and minimally invasive technique for routine use in experiments, aimed at hypothesis testing of the capabilities of cardiac regenerative therapeutics in the rabbit model. Once competency is achieved, the whole procedure can be performed within 25 min after anaesthetizing the rabbit.

Novel therapeutic strategies in cardiac regenerative medicine require extensive and detailed studies in large preclinical animal models before they can be considered for use in humans. Here, we demonstrate a percutaneous contrast echocardiography-guided intramyocardial injection technique in rabbits, which is valuable for hypothesis testing the efficacy of such novel therapies.

经皮超声心动图引导心肌注射液与大鼠前体细胞的临床研究

Cell and gene therapy are exciting and promising strategies for the purpose of cardiac regeneration in the setting of heart failure with reduced ejection ...

A Pleural Effusion Model in Rats by Intratracheal Instillation of Polyacrylate/Nanosilica

Pleural effusion is a prevalent clinical finding of many pulmonary diseases. Having a useful animal pleural effusion model is very important to study these pulmonary diseases. Previous pleural effusion models paid more attention to biological factors rather than nanoparticles in the environment. Here, we introduce a model to make pleural effusion in rats by intratracheal instillation of polyacrylate/nanosilica, and a method of nanoparticle isolation in the pleural effusion. By intratracheal instillation of polyacrylate/nanosilica with concentrations of 3.125, 6.25 and 12.5 mg/kg&#8729;mL, the pleural effusion in rats presented on day 3, peaked at days 7-10 in 6.25 and 12.5 mg/kg&#8729;mL groups, then slowly decreased and disappeared on day 14. When the concentration of polyacrylate/nanosilica increased, the pleural effusion is produced more and faster. This pleural fluid was detected by ultrasound examination or CT chest scanning and confirmed by dissection of rats. Silica nanoparticles were observed in the rats' pleural effusion by transmission electron microscope. These results showed that the exposure to polyacrylate/nanosilica leads to the induction of pleural effusion, which was consistent with our previous report in humans. Additionally, this model is beneficial for the further study of nanotoxicology and the pleural effusion diseases.

Here, we present a protocol to construct a pleural effusion model in rats by intratracheal instillation of polyacrylate/nanosilica.

聚丙烯酸/纳米水的气管内灌注积液模型

Pleural effusion is a prevalent clinical finding of many pulmonary diseases. Having a useful animal pleural effusion model is very important to study ...

Continuous Venous-Arterial Doppler Ultrasound During a Preload Challenge

A preload challenge (PC) is a clinical maneuver that, first, increases the cardiac filling (i.e., preload) and, second, calculates the change in cardiac output. Fundamentally, a PC is a bedside approach for testing the Frank-Starling-Sarnoff (i.e., "cardiac function") curve. Normally, this curve has a steep slope such that a small change in the cardiac preload generates a large change in the stroke volume (SV) or cardiac output. However, in various disease states, the slope of this relationship flattens such that increasing the volume into the heart leads to little rise in the SV. In this pathological scenario, additional cardiac preload (e.g., intravenous fluid) is unlikely to be physiologically effective and could lead to harm if organ congestion evolves. Therefore, inferring both the cardiac preload and output is clinically useful as it may guide intravenous (IV) fluid resuscitation. Accordingly, the goal of this protocol is to describe a method for contemporaneously tracking the surrogates of cardiac preload and output using a novel, wireless, wearable ultrasound during a well-validated preload challenge.

The Frank-Starling-Sarnoff curve is clinically important and describes the relationship between cardiac preload and output. This report illustrates a novel method of simultaneous jugular venous and carotid arterial Doppler velocimetry as transient surrogates of cardiac preload and output, respectively; this approach is enabled by wireless, wearable Doppler ultrasound.

负荷前激发期间的连续静脉动脉多普勒超声检查

A preload challenge (PC) is a clinical maneuver that, first, increases the cardiac filling (i.e., preload) and, second, calculates the change in cardiac ...

A Modified Sonographic Algorithm for Image Acquisition in Life-Threatening Emergencies in the Critically Ill Newborn

The use of routine point-of-care ultrasound (POCUS) is increasing in neonatal intensive care units (NICUs), with several centers advocating for 24 h equipment availability. In 2018, the sonographic algorithm for life-threatening emergencies (SAFE) protocol was published, which allows the assessment of neonates with sudden decompensation to identify abnormal contractility, tamponade, pneumothorax, and pleural effusion. In the study unit (with a consulting neonatal hemodynamics and POCUS service), the algorithm was adapted by including consolidated core steps to support at-risk newborns, aiding clinicians in managing cardiac arrest, and adding views to verify correct intubation. This paper presents a protocol that can be applied in the NICU and the delivery room (DR) in relation to three scenarios: cardiac arrest, hemodynamic deterioration, or respiratory decompensation. 
This protocol can be performed with a state-of-the-art ultrasound machine or an affordable handheld device; the image acquisition protocol is carefully detailed. This method was designed to be learned as a general competence to obtain the timely diagnosis of life-threatening scenarios; the method aims to save time but does not represent a substitute for comprehensive and standardized hemodynamic and radiological analyses by a multidisciplinary team, which might not universally be on call but needs to be involved in the process. From January 2019 to July 2022, in our center, 1,045 hemodynamic consultation/POCUS consults were performed with 25 patients requiring the modified SAFE protocol (2.3%), and a total of 19 procedures were performed. In five cases, trained fellows on call resolved life-threatening situations. Clinical examples are provided that show the importance of including this technique in the care of critical newborns.

Here, we present a protocol that can be applied in the neonatal intensive care unit and the delivery room in relation to three scenarios: cardiac arrest, hemodynamic deterioration, or respiratory decompensation. This protocol can be performed with a state-of-the-art ultrasound machine or an affordable handheld device; an image acquisition protocol is carefully detailed.

一种改进的超声算法，用于危重新生儿危及生命的急症图像采集

The use of routine point-of-care ultrasound (POCUS) is increasing in neonatal intensive care units (NICUs), with several centers advocating for 24 h ...