TWP was funded by the Irish Cardiac Society Brian McGovern Travelling Fellowship. WTP was funded by R01 HL095712 and an AHA Established Investigator Award.

Todos los pasos descritos se realizaron bajo los protocolos aprobados por el Comité de Cuidado y Uso de Animales Institucional del Hospital Infantil de Boston. 1. Preparación <ol><li> Realizar la evaluación anatómica y funcional cardiaca por ecocardiografía línea de base antes de comenzar el protocolo de inyección, ya que la posición del transductor fijo óptimo para la inyección intramiocárdica puede no producir las vistas estándar óptimas para delinear la anatomía y la evaluación de la función. </li><li> La configuración de la inyección se muestra en las Figuras 1A-1C. Coloque una jeringa vacía con una aguja enfundada, orientada bisel hacia arriba, en la abrazadera de la jeringa (ver Figura 1C) y asegurar la sonda de transductor de ultrasonidos en la abrazadera de exploración de la cabeza (véase la Figura 1B). Aflojar el scan-cabeza de la articulación de bloqueo de bolas abrazadera (Figura 1B) y manipular la orientación del transductor de manera que está alineado en paralelo al eje de la aguja. Fijar el SCAN-posición de la cabeza apretando el conjunto de bloqueo de bolas abrazadera exploración de cabeza. NOTA: Para la inyección en ratones adultos, una aguja de 30 G con un 1 in / 2,5 cm de longitud es óptima. Una jeringa de 1 ml se puede utilizar para volúmenes más grandes, mientras que una jeringa estanca a los gases puede ser utilizado para un control más preciso de volúmenes más pequeños (5-10 l). </li><li> Aplicar gel de ultrasonido liberalmente a la punta del transductor con una espátula para cubrir la cabeza a lo largo de su totalidad. Desenvainar cuidadosamente la aguja y el uso de la aguja de montaje controles para avanzar la aguja justo debajo del transductor y en el gel de ultrasonido para la visualización. Hacer ajustes menores utilizando la aguja de montaje de control de modo que la aguja se visualiza claramente a lo largo de su longitud en la imagen de ultrasonido. Si el transductor se correctamente alineado paralelo a la aguja en el paso 1.4, a continuación, la aguja debe permanecer dentro del plano de la imagen a medida que avanza y se retira con el mando de control de la inyección (Figura 1C). </li><li> En etapas posteriores, no molestar la necesidadLE / transductor alineación horizontal moviendo ya sea en el eje horizontal. Más bien, apuntar a áreas específicas del corazón para inyección cambiando la posición vertical (eje y) de la aguja de montar y moviendo la plataforma animal. </li><li> Mueva el transductor superiormente desde la plataforma animal, mediante la exploración de control de altura (Figura 1B) para permitir la posterior colocación del ratón anestesiado en la plataforma animal. Esto no perturbar la alineación del eje x del transductor al eje largo de la aguja. </li><li> Retire la jeringa que se utilizó para la alineación de la abrazadera de la jeringa y desechar cuidadosamente. Cargue la aguja y jeringa con la sustancia inyectada al volumen de destino final, teniendo en cuenta el espacio muerto en la punta de la jeringa. Tenga cuidado de eliminar las burbujas de aire. Coloque la jeringa en la abrazadera de la jeringa sin ajustar su alineamiento eje x. Retraer completamente la jeringa con el control de la inyección. NOTA: Para los propósitos iniciales de formación, el uso de azul de Evanscolorante (1%), mancha azul tripán (0,4%) o una suspensión de microesferas fluorescentes como el inyectado puede ayudar al operador a confirmar la competencia y el éxito de la inyección objetivo. </li></ol> 2. Inyección <ol><li> Encienda el calentador integrado de la plataforma de calefacción y configurarlo para 37 ° C. Coloque la plataforma de animales 180 ° de la orientación de imagen de rutina, con la abrazadera de la manguera de anestesia y la cabeza del animal más próximo al operador. Esto permite que el corazón (en el lado izquierdo del pecho) para ser ipsilateral a la abrazadera de la jeringa y la aguja. Nota: Los ajustes de rotación menor en sentido horario, además, a la plataforma de los animales pueden ser necesarios para orientar correctamente el corazón para el plano paraesternal eje corto de imagen que se utilizará para la inyección (Figura 2A). </li><li> Preparar los ratones para la ecocardiografía como se informó anteriormente 9. Anestesiar el ratón en una cámara de inducción con 2% de isoflurano. Eliminar el vello del pecho con el pelo crema de eliminación de und aplicar gel lubricante a ambos ojos para evitar el secado de la esclerótica. </li><li> Elevar el transductor mediante la exploración de control de altura de la cabeza (Figura 1B). Coloque la supina anestesiado ratón encima de la plataforma de los animales se calienta con el hocico dentro de un cono de la nariz entrega 1-3% isoflurano (Figuras 2A-2B). Suavemente inserte una sonda rectal y la cinta de las cuatro patas a los electrodos de ECG, la aplicación de gel de electrodos para el contacto eléctrico. NOTA: El nivel adecuado de anestesia se debe garantizar un trato humanitario de los animales. No debe haber ningún cambio en la frecuencia cardíaca y sin respuesta a la colocación de la aguja a través de la pared torácica. Controles de temperatura homeostática integradas de la plataforma de los animales deben ser utilizados para manutención de la temperatura (37 ± 0,5 ° C), como la hipotermia dará lugar a bradicardia relativa, dilatación ventricular, y posibles molestias. </li><li> Una vez que el ratón es seguro en la plataforma animal, bajar el transductor sobre la depilaTed pecho usando el análisis de control de altura de la cabeza (Figura 1B). La configuración de ultrasonido óptimo para la inyección es para el corazón para ser visualizado en la orientación del eje corto paraesternal, según la técnica ecocardiográfica estándar. Gire la plataforma animales 20-30 ° hacia la derecha para obtener la ventana acústica óptima para la inyección en el plano de imagen de eje corto (Figuras 2A-2B). Nota: Como alternativa, la inyección se puede realizar a partir de una orientación del eje longitudinal paraesternal en sentido contrario a las agujas del reloj de la plataforma de los animales (Figura 2C). </li><li> Use los controles de ajuste de la plataforma de animales para ajustar el campo de visión y para dirigirse a cualquier sitio de la inyección deseada en el miocardio del ventrículo izquierdo. Pan de ida y vuelta desde el ápice a la base de corazón para apuntar a la ubicación de inyección deseado en el miocardio del ventrículo izquierdo (Figuras 3A-3C). Nota: El paraesternal de eje corto midpapillary (Figura 3A) ofrece reproducible hitos que permiten imágenes de seguimiento del sitio de la inyección. Nota: Como alternativa, el eje largo paraesternal se puede utilizar para llegar a un sitio predefinido inyección (Figura 3D). </li><li> Comenzando con la jeringa en la abrazadera de la jeringa completamente retraído, avanzar lentamente la jeringa hacia el pecho del animal girando las agujas del reloj de control de la inyección (Figura 4A). Para permitir la visualización clara de ultrasonido de tanto el corazón y la punta de la aguja a medida que se acerca al pecho, utilizar un montón de gel de ultrasonido sobre el lado izquierdo del pecho y optimizar la ventana acústica mediante el establecimiento de un amplio campo de visión en los controles ecocardiográficos. Ajuste el punto / zona focal en el sitio diana para la inyección. Los ajustes menores a la aguja de montaje controles pueden optimizar la imagen de la aguja a lo largo de su longitud. NOTA: Algunas máquinas de ultrasonido tienen una función de software de guía de la aguja para ampliar digitalmente una línea a lo largo del eje largo de la aguja a través de al miocardio objetivo(Figura 4B). Esta herramienta de software puede ser útil, pero no es esencial. </li><li> Con el animal sedado adecuadamente (1-3% de isoflurano mezclado con 0,5-0,8 L / min 100% de oxígeno), avanzar la aguja a través de la pared torácica del ratón y en el miocardio, observando cuidadosamente la posición de la punta de la aguja biselada en absoluto veces. Detener el avance cuando la punta de la aguja está dentro del miocardio objetivo (Figura 4C). La punta biselada entera debe ser segura dentro del miocardio, para evitar la fuga de la sustancia inyectada en el espacio pericárdico. </li><li> Cuando la punta está en la ubicación deseada, entregar el inyectado empujando el émbolo de la jeringa. Entregar el producto a inyectar lentamente, durante 5 a 30 segundos (dependiendo del volumen que se entrega). Hasta 50 l de solución inyectada se pueden entregar sin comprometer la función ventricular. Un aspecto echobright transitoria a la región del miocardio inyectado puede ser evidente después de la inyección con éxito. Un período breve (segundos) de bradycard relativaia en ocasiones se observó con la inyección en el miocardio y rápidamente se resuelve. </li><li> Una vez que se ha administrado la sustancia inyectada, retirar rápidamente la aguja por el giro hacia la izquierda de la perilla de control de la inyección. El ratón debe mantenerse bajo anestesia durante varios minutos de observación ecocardiográfica para confirmar la función ventricular preservada y sin complicaciones después del procedimiento. Si está indicado, múltiples regiones de miocardio pueden ser inyectados en serie mediante el reposicionamiento del ángulo de la aguja de enfoque mediante el ajuste de la plataforma animal. Después de la inyección intramiocárdica, el ratón se coloca en una jaula en su propia y permitió recuperarse de la anestesia bajo observación. </li><li> No deje un animal sin vigilancia hasta que se haya recuperado el conocimiento suficiente para mantener decúbito esternal. No devuelva un animal que ha sufrido la inyección intramiocárdica de la compañía de otros animales hasta que se recupere completamente. La jaula debe ser colocado sobre una almohadilla de termorregulación con ready provisión de agua y el ratón dieta. No se espera que las molestias después del procedimiento y el fracaso para reanudar adecuadamente el comportamiento normal poco después de la intervención sugiere una posible complicación (ver Discusión). </li><li> Deseche cuidadosamente la aguja inmediatamente después de la finalización de la inyección intramiocárdica para minimizar el riesgo de lesiones cortopunzantes al operador oa terceros. La reutilización de una aguja puede resultar en embotamiento de la punta por lo que es más difícil de perforar el miocardio y que resulta en un mayor riesgo de complicación. </li></ol>

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The authors have nothing to disclose.

Los biológicos se pueden entregar al miocardio por inyección intramiocárdica directa, inyección intrapericárdica, o administración indirecta a través del torrente sanguíneo. Ensayos de terapia basados ​​en células recientes en modelos de infarto de miocardio han descrito un enfoque de toracotomía abierta a la entrega de la sustancia inyectada 12-14. Un factor importante en el éxito de una intervención terapéutica de miocardio depende de la elección de la ruta de entrega. La dosis más alta d...

La enfermedad cardíaca es la principal causa de muerte tanto para hombres y mujeres en los Estados Unidos, lo que representa 600.000 muertes al año 1. Los modelos murinos de enfermedad cardiovascular son de importancia crítica para la investigación de los mecanismos fisiopatológicos y para explorar posibles terapias. Infarto de entrega de vectores de terapia génica, las células, los ARN modificados, y otros agentes terapéuticos permisos de investigación de su potencial terapéutico para la enfermedad cardíaca 2-7 tallo. En la actualidad, hay opciones limitadas para la entrega infarto de agentes terapéuticos en modelos de ratón 6. Inyección intramiocárdica bajo visualización directa se usa comúnmente, pero requiere una esternotomía o toracotomía y se limita a la región expuesta del corazón. Aunque esto es conveniente cuando se realiza en el momento de otra manipulación experimental, como la ligadura de LAD, la necesidad de un procedimiento invasivo para la entrega intramyocardial limita posibles diseños experimentales e introduce unefectos adicionales A partir del procedimiento (por ejemplo, la fibrosis debido a toracotomía). Entrega pericárdico percutáneo de vectores virales se ha informado, pero el sitio y la distribución de agente terapéutico no es homogénea y es difícil de controlar 8. Resultados de inyección percutáneo de distribución más homogénea de material inyectado, pero la entrega coronaria eficiente y reproducible es un reto en modelos murinos. A continuación, describimos una técnica de inyección cerrado pecho intramyocardial que permite al operador controlar la orientación mínimamente invasiva, de agentes terapéuticos bajo guía ecográfica. La técnica es fácil de aprender, evita la necesidad de toracotomía o esternotomía y sus complicaciones experimentales concomitantes, y proporciona una mayor flexibilidad en el calendario y los sitios de la inyección intramiocárdica. Por lo tanto, la inyección intramiocárdica ecocardiografía asistida representa un método técnicamente simple y altamente efectiva de manipular elmiocardio en modelos experimentales murinos.

<table border="0" cellpadding="0" cellspacing="0" width="743">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:313px;">Vevo 2100 ultrasound imaging system&#160;</td>
			<td style="width:144px;">Visualsonics</td>
			<td style="width:119px;"></td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:313px;">Vevo Integrated Rail System III</td>
			<td style="width:144px;">Visualsonics</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:313px;">Microscan MS400 transducer</td>
			<td style="width:144px;">Visualsonics</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:313px;">Microscan MS550D transducer</td>
			<td style="width:144px;">Visualsonics</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:313px;">PrecisionGlide needles</td>
			<td style="width:144px;">BD</td>
			<td style="width:119px;">305128</td>
			<td>30G x 1 inch</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:313px;">1cc slip tip syringe</td>
			<td style="width:144px;">Exel International&#160;</td>
			<td style="width:119px;">26048</td>
			<td>or equivalent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:313px;">Gastight 50ul glass syringes</td>
			<td style="width:144px;">Hamilton&#160;</td>
			<td style="width:119px;">1705</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:313px;">Trypan blue stain (0.4%)</td>
			<td style="width:144px;">Gibco&#160;</td>
			<td style="width:119px;">15250</td>
			<td>or equivalent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:313px;">Isoflurane</td>
			<td style="width:144px;">Baxter</td>
			<td style="width:119px;">AHN3640</td>
			<td>or equivalent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:313px;">Aquasonic 100</td>
			<td style="width:144px;">Parker Laboratories</td>
			<td style="width:119px;">(01-08)</td>
			<td>or equivalent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:313px;">Polystyrene microspheres (red fluorescent)</td>
			<td style="width:144px;">Life Technologies</td>
			<td style="width:119px;">F-8842</td>
			<td>or equivalent</td>
		</tr>
	</tbody>
</table>

ultrasound-guided transthoracic intramyocardial injection in mice

Los modelos murinos de enfermedad cardiovascular son importantes para la investigación de los mecanismos fisiopatológicos y la exploración de potenciales terapias regenerativas. Los experimentos que implican la inyección miocárdica se llevan a cabo actualmente por el acceso quirúrgico directo a través de una toracotomía. Aunque esto es conveniente cuando se realiza en el momento de otra manipulación experimental como la ligadura de la arteria coronaria, la necesidad de un procedimiento invasivo para la entrega intramyocardial limita posibles diseños experimentales. Con cada vez mejor resolución ultrasonido y técnicas de imagen no invasivas avanzadas, ahora es factible realizar rutinariamente guiada por ecografía, la inyección intramiocárdica percutánea. Esta modalidad ofrece eficiente y fiable agentes a una región específica del miocardio. Las ventajas de esta técnica son evitar la morbilidad quirúrgica, la facilidad para las regiones objetivo de miocardio selectivamente bajo control ecográfico, y la oportunidad de ofrecer a inyectar a la myocardium en múltiples intervalos de tiempo, predeterminadas. Con técnica practicada, complicaciones de la inyección intramiocárdica son raros, y los ratones regresar rápidamente a la actividad normal en la recuperación de la anestesia. Siguiendo los pasos descritos en este protocolo, el operador con experiencia básica ecocardiografía puede convertirse rápidamente competente en esta técnica versátil, mínimamente invasivo.

Inyección intramiocárdica murino con colorante azul o microesferas fluorescentes La inyección de colorante azul de Evan es útil para fines de capacitación. Pronto después de la inyección, la eutanasia el ratón y quitar el corazón para visualizar la ubicación de la inyección de colorante azul. Figura 5 muestra un ejemplo de una inyección de éxito, con colorante azul de infiltrarse en el miocardio a nivel muscular mediados papilares (Figura 5A, regi?...

Watch this Scientific Journal Video about Ultrasound-guided Transthoracic Intramyocardial Injection in Mice at JoVE.com

Ultrasound-guided Transthoracic Intramyocardial Injection in Mice

Inyección intramiocárdica percutánea guiada por ecocardiografía representa una modalidad eficiente, fiable, y objeto de orientación para la entrega de agentes de transferencia de genes o células en el corazón murino. Siguiendo los pasos descritos en este protocolo, el operador puede convertirse rápidamente competente en esta técnica versátil, mínimamente invasivo.

Guiada por ecografía transtorácica intramiocárdica inyección en ratones

Murine models of cardiovascular disease are important for investigating pathophysiological mechanisms and exploring potential regenerative therapies. ...

ultrasound-guided-transthoracic-intramyocardial-injection-in-mice

Research

JoVE Journal

Medicine

14.7K vistas.  Boston Children's Hospital.  Inyección intramiocárdica percutánea guiada por ecocardiografía representa una modalidad eficiente, fiable, y objeto de orientación para la entrega de agentes de transferencia de genes o células en el corazón murino. Siguiendo los pasos descritos en este protocolo, el operador puede convertirse rápidamente competente en esta técnica versátil, mínimamente invasivo. 

Video: Ultrasound-guided Transthoracic Intramyocardial Injection in Mice

Transthoracic Echocardiography in Mice

In recent years, murine models have become the primary avenue for studying the molecular mechanisms of cardiac dysfunction resulting from changes in gene expression. Transgenic and gene targeting methods can be used to generate mice with altered cardiac size and function,1-3 and as a result, in vivo techniques are needed to evaluate their cardiac phenotype. Transthoracic echocardiography, pulse wave Doppler (PWD), and tissue Doppler imaging (TDI) can be used to provide dimensional measurements of the mouse heart and to quantify the degree of cardiac systolic and diastolic performance. Two-dimensional imaging is used to detect abnormal anatomy or movements of the left ventricle, whereas M-mode echo is used for quantification of cardiac dimensions and contractility.4,5 In addition, PWD is used to quantify localized velocity of turbulent flow,6 whereas TDI is used to measure the velocity of myocardial motion.7 Thus, transthoracic echocardiography offers a comprehensive method for the noninvasive evaluation of cardiac function in mice.

Transthoracic echocardiography offers a noninvasive method for the evaluation of cardiac function in mice. A combination of ultrasound and Doppler imaging modalities can be used to obtain dimensional measurements of the heart and intracardiac blood flow, which together provide an assessment of cardiac systolic and diastolic performance.

Ecocardiografía transtorácica en ratones

In recent years, murine models have become the primary avenue for studying the molecular mechanisms of cardiac dysfunction resulting from changes in gene ...

Investigación

Medicina

Coronary Artery Ligation and Intramyocardial Injection in a Murine Model of Infarction

Mouse models are a valuable tool for studying acute injury and chronic remodeling of the myocardium in vivo. With the advent of genetic modifications to the whole organism or the myocardium and an array of biological and/or synthetic materials, there is great potential for any combination of these to assuage the extent of acute ischemic injury and impede the onset of heart failure pursuant to myocardial remodeling. 
Here we present the methods and materials used to reliably perform this microsurgery and the modifications involved for temporary (with reperfusion) or permanent coronary artery occlusion studies as well as intramyocardial injections. The effects on the heart that can be seen during the procedure and at the termination of the experiment in addition to histological evaluation will verify efficacy. 
Briefly, surgical preparation involves anesthetizing the mice, removing the fur on the chest, and then disinfecting the surgical area. Intratracheal intubation is achieved by transesophageal illumination using a fiber optic light. The tubing is then connected to a ventilator. An incision made on the chest exposes the pectoral muscles which will be cut to view the ribs. For ischemia/reperfusion studies, a 1 cm piece of PE tubing placed over the heart is used to tie the ligature to so that occlusion/reperfusion can be customized. For intramyocardial injections, a Hamilton syringe with sterile 30gauge beveled needle is used. When the myocardial manipulations are complete, the rib cage, the pectoral muscles, and the skin are closed sequentially. Line block analgesia is effected by 0.25% marcaine in sterile saline which is applied to muscle layer prior to closure of the skin. The mice are given a subcutaneous injection of saline and placed in a warming chamber until they are sternally recumbent. They are then returned to the vivarium and housed under standard conditions until the time of tissue collection. At the time of sacrifice, the mice are anesthetized, the heart is arrested in diastole with KCl or BDM, rinsed with saline, and immersed in fixative. Subsequently, routine procedures for processing, embedding, sectioning, and histological staining are performed. 
Nonsurgical intubation of a mouse and the microsurgical manipulations described make this a technically challenging model to learn and achieve reproducibility. These procedures, combined with the difficulty in performing consistent manipulations of the ligature for timed occlusion(s) and reperfusion or intramyocardial injections, can also affect the survival rate so optimization and consistency are critical.

Numerous genetic manipulations and/or intramyocardial injections of genes, proteins, cells, and/or biomaterials are superimposed upon the dimension of time in studies of acute ischemia/ reperfusion injury and chronic remodeling in mice. This video illustrates the microsurgical procedures for ischemia/reperfusion, permanent coronary artery ligation, and intramyocardial injection studies.

Ligadura de las arterias coronarias y la inyección intramiocárdica en un modelo murino de infarto

Mouse models are a valuable tool for studying acute injury and chronic remodeling of the myocardium in vivo.  With the advent of genetic modifications to ...

Intramyocardial Cell Delivery: Observations in Murine Hearts

Previous studies showed that cell delivery promotes cardiac function amelioration by release of cytokines and factors that increase cardiac tissue revascularization and cell survival. In addition, further observations revealed that specific stem cells, such as cardiac stem cells, mesenchymal stem cells and cardiospheres have the ability to integrate within the surrounding myocardium by differentiating into cardiomyocytes, smooth muscle cells and endothelial cells.
Here, we present the materials and methods to reliably deliver noncontractile cells into the left ventricular wall of immunodepleted mice. The salient steps of this microsurgical procedure involve anesthesia and analgesia injection, intratracheal intubation, incision to open the chest and expose the heart and delivery of cells by a sterile 30-gauge needle and a precision microliter syringe.
Tissue processing consisting of heart harvesting, embedding, sectioning and histological staining showed that intramyocardial cell injection produced a small damage in the epicardial area, as well as in the ventricular wall. Noncontractile cells were retained into the myocardial wall of immunocompromised mice and were surrounded by a layer of fibrotic tissue, likely to protect from cardiac pressure and mechanical load.

Intramyocardial cell delivery in murine models of cardiovascular diseases, such as hypertension or myocardial infarction, is widely used to test the therapeutic potential of different cell types in regenerative studies. Therefore, a detailed description and a clear visualization of this surgical procedure will help to define the limits and advantages of cardiovascular cell therapeutic analyses in small rodents.

Intramiocárdica celular de la entrega: Las observaciones en murinos Hearts

Previous studies showed that cell delivery promotes cardiac function amelioration by release of cytokines and factors that increase cardiac tissue ...

Substernal Thyroid Biopsy Using Endobronchial Ultrasound-guided Transbronchial Needle Aspiration

Substernal thyroid goiter (STG) represents about 5.8% of all mediastinal lesions1. There is a wide variation in the published incidence rates due to the lack of a standardized definition for STG. Biopsy is often required to differentiate benign from malignant lesions. Unlike cervical thyroid, the overlying sternum precludes ultrasound-guided percutaneous fine needle aspiration of STG. Consequently, surgical mediastinoscopy is performed in the majority of cases, causing significant procedure related morbidity and cost to healthcare. Endobronchial Ultrasound-guided Transbronchial Needle Aspiration (EBUS-TBNA) is a frequently used procedure for diagnosis and staging of non-small cell lung cancer (NSCLC). Minimally invasive needle biopsy for lesions adjacent to the airways can be performed under real-time ultrasound guidance using EBUS. Its safety and efficacy is well established with over 90% sensitivity and specificity. The ability to perform EBUS as an outpatient procedure with same-day discharges offers distinct morbidity and financial advantages over surgery. As physicians performing EBUS gained procedural expertise, they have attempted to diversify its role in the diagnosis of non-lymph node thoracic pathologies. We propose here a role for EBUS-TBNA in the diagnosis of substernal thyroid lesions, along with a step-by-step protocol for the procedure.

Substernal thyroid lesions are common, and need to be differentiated from malignancy. Obtaining percutaneous fine needle biopsy is not possible due to its retrosternal location. This article proposes a protocol for biopsy of substernal thyroid lesions using Endobronchial Ultrasound-guided Transbronchial Needle Aspiration (EBUS-TBNA).

Subesternal tiroides Biopsia Usando guiada por ecografía endobronquial punción transbronquial

Substernal thyroid goiter (STG) represents about 5.8% of all mediastinal lesions1. There is a wide variation in the published incidence rates due to the ...

Ultrasound-guided Botulinum Toxin-A Injections: A Method of Treating Sialorrhea

Neurological diseases can be complicated by sialorrhea, an excessive flow of saliva. Patients suffering from moderate to severe sialorrhea have an impaired quality of life, often worsened by correlated complications such as aspiration pneumonia, oral infections, dental caries, and maceration of the skin. Diverse therapeutic approaches have been proposed for the treatment of sialorrhea, including surgery and the use of anticholinergic agents, with limited results and the possible occurrence of serious adverse events. Recently, botulinum toxin (BoNT) injection within the major salivary glands has been proposed in patients refractory to anticholinergic therapy, with the aim of inhibiting local acetylcholine release and gland activity. 
In order to obtain a better outcome in terms of reduction of saliva production, efficacy, duration, and avoidance of major adverse events, we developed an ultrasound-guided BoNT-type A injection technique accurately described in the text. Here we present a method of treating sialorrhea with bilateral parotid and submandibular gland BoNT-type A injections under ultrasound guidance. Four quadrants of the parotid gland and two quadrants of the submandibular gland are visualized and injected using two accesses and one access, respectively. 
The ultrasound-guided procedure provides a simple, non-invasive, real-time visualization of the muscular and glandular tissues and their surrounding structures, optimizing treatment efficacy and safety.

Botulinum toxin is injected into the salivary glands for the treatment of sialorrhea. The ultrasound-guided botulinum toxin injection in both the parotid and submandibular glands demonstrates a sustained efficacy and the absence of serious side effects.

Guiada por ultrasonografía Inyecciones de toxina botulínica-A: Un método para tratar sialorrea

Neurological diseases can be complicated by sialorrhea, an excessive flow of saliva. Patients suffering from moderate to severe sialorrhea have an ...

Ultrasound-guided Intracardiac Injection of Human Mesenchymal Stem Cells to Increase Homing to the Intestine for Use in Murine Models of Experimental Inflammatory Bowel Diseases

Crohn&#39;s disease (CD) is a common chronic inflammatory disease of the small and large intestines. Murine and human mesenchymal stem cells (MSCs) have immunosuppressive potential and have been shown to suppress inflammation in mouse models of intestinal inflammation, even though the route of administration can limit their homing and effectiveness 1,3,4,5. Local application of MSCs to colonic injury models has shown greater efficacy at ameliorating inflammation in the colon. However, there is paucity of data on techniques to enhance the localization of human bone marrow-derived MSCs (hMSCs) to the small intestine, the site of inflammation in the SAMP-1/YitFc (SAMP) model of experimental Crohn&#39;s disease. This work describes a novel technique for the ultrasound-guided intracardiac injection of hMSCs in SAMP mice, a well-characterized spontaneous model of chronic intestinal inflammation. Sex- and age-matched, inflammation-free AKR/J (AKR) mice were used as controls. To analyze the biodistribution and the localization, hMSCs were transduced with a lentivirus containing a triple reporter. The triple reporter consisted of firefly luciferase (fl), for bioluminescent imaging; monomeric red fluorescent protein (mrfp), for cell sorting; and truncated herpes simplex virus thymidine kinase (ttk), for positron emission tomography (PET) imaging. The results of this study show that 24 h after the intracardiac administration, hMSCs localize in the small intestine of SAMP mice as opposed to inflammation-free AKR mice. This novel, ultrasound-guided injection of hMSCs in the left ventricle of SAMP mice ensures a high success rate of cell delivery, allowing for the rapid recovery of mice with minimal morbidity and mortality. This technique could be a useful method for the enhanced localization of MSCs in other models of small-intestinal inflammation, such as TNF&#916;RE6. Future studies will determine if the increased localization of hMSCs by intra-arterial delivery can lead to increased therapeutic efficacy.

Murine studies in models of colonic inflammation have demonstrated that a small percentage (1 - 5%) of mesenchymal stem cells (MSC) injected intravenously or intraperitoneally home to the inflamed colon1,2. This study shows that ultrasound-guided intracardiac injections of MSCs result in increased localization to the intestine.

Guiado por ecografía intracardiaca inyección de células madre mesenquimales humanas para aumentar autoguiado hacia el blanco en el intestino para su uso en modelos murinos de enfermedades de intestino inflamatorias experimentales

Crohn&#39;s disease (CD) is a common chronic inflammatory disease of the small and large intestines. Murine and human mesenchymal stem cells (MSCs) have ...

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.

Inyección de contraste percutánea guiada por ecocardiografía intramiocárdica y entrega de celular en un modelo preclínico grande

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

Transthoracic Echocardiographic Examination in the Rabbit Model

Large animal models such as the rabbit are valuable for translational preclinical research. Rabbits have a similar cardiac electrophysiology compared to that of humans and that of other large animal models such as dogs and pigs. However, the rabbit model has the additional advantage of lower maintenance costs compared to other large animal models. The longitudinal evaluation of cardiac function using echocardiography, when appropriately implemented, is a useful methodology for preclinical assessment of novel therapies for heart failure with reduced ejection fraction (e.g. cardiac regeneration). The correct use of this non-invasive tool requires the implementation of a standardized examination protocol following international guidelines. Here we describe, step by step, a detailed protocol supervised by veterinary cardiologists for performing echocardiography in the rabbit model, and demonstrate how to correctly obtain the different echocardiographic views and imaging planes, as well as the different imaging modes available in a clinical echocardiography system routinely used in human and veterinary patients.

Here we describe, step by step, a detailed protocol for performing echocardiography in the rabbit model. We show how to correctly obtain the different echocardiographic views and imaging planes, as well as the different imaging modes available in a clinical echocardiography system routinely used in human and veterinary patients.

Examen Ecocardiográfico Transtorácico en el Modelo Conejo

Large animal models such as the rabbit are valuable for translational preclinical research. Rabbits have a similar cardiac electrophysiology compared to ...

Endoscopic Ultrasound-Guided Biliary Drainage: Endoscopic Ultrasound-Guided Hepaticogastrostomy in Malignant Biliary Obstruction

Patients with unresectable malignant biliary obstruction often require biliary drainage to decompress the biliary system. Endoscopic Retrograde Cholangiopancreatography (ERCP) is the primary biliary drainage method whenever possible. Percutaneous Transhepatic Biliary Drainage (PTBD) is used as a salvage method if ERCP fails. Endoscopic Ultrasound-Guided Biliary Drainage (EUS-BD) provides a feasible alternative biliary drainage method where one of the methods is EUS guided Hepaticogastrostomy (EUS-HGS). Here we describe the EUS-HGS technique in a case of unresectable malignant hilar biliary obstruction to achieve biliary drainage.
Presented here is the case of a 71-year-old female with painless jaundice and weight loss for 2 weeks. Computed Tomography (CT) imaging showed a 4 x 5 cm hilar tumor with lymphadenopathy and liver metastasis. EUS fine needle biopsy (FNB) of the lesion was consistent with cholangiocarcinoma. Her bilirubin levels were 212 &#181;mol/L (&lt;15) during presentation.
A linear echoendoscope was used to locate the left dilated intrahepatic ducts (IHD) of the liver. The segment 3 dilated IHD was identified and punctured using a 19 G needle. Contrast was used to opacify the IHDs under fluoroscopic guidance. The IHD was cannulated using a 0.025-inch guidewire. This was followed by the dilation of the fistula tract using a 6 Fr electrocautery dilator along with a 4 mm biliary balloon dilator. A partially covered metallic stent of 10 cm in length was deployed under fluoroscopic guidance. The distal part opens in the IHD and the proximal part was deployed within the working channel of the echoendoscope that subsequently released into the stomach. The patient was discharged three days after the procedure. Follow up performed in the second and fourth weeks showed that the bilirubin levels were 30 &#181;mol/L and 14 &#181;mol/L, respectively. This indicates that EUS-HGS is a safe method for biliary drainage in unresectable malignant biliary obstruction.

Endoscopic Ultrasound-Guided Biliary Drainage (EUS-BD) is an alternative method of biliary decompression in malignant biliary obstruction. Here we describe the technique of EUS guided-Hepaticogastrostomy (EUS-HGS) in a case of unresectable malignant hilar biliary obstruction.

Drenaje biliar guiado por ultrasonido endoscópico: hepaticogastrostomía endoscópica guiada por ultrasonido en la obstrucción biliar maligna

Patients with unresectable malignant biliary obstruction often require biliary drainage to decompress the biliary system. Endoscopic Retrograde ...

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.

Implantación de cardiomiocitos derivados de células madre pluripotentes inducida por ultrasonido en ratones con infartado de miocardio

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