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 os passos descritos foram realizados no âmbito de protocolos aprovados pelo Comitê de Cuidados e Uso do Hospital Infantil de Boston Animais Institucional. 1 Preparação <ol><li> Realizar avaliação anatômica e funcional cardíaca inicial por ecocardiografia antes de iniciar o protocolo de injeção, como a posição do transdutor fixo ideal para injeção transmural pode não produzir as ótimas vistas padrão para delinear a anatomia ea avaliação da função. </li><li> A configuração da injecção é mostrado nas figuras 1A-1C. Coloque uma seringa vazia com uma agulha com bainha, para cima orientada cônicas, na braçadeira seringa (ver Figura 1C) e fixe a sonda transdutor de ultra-som no grampo varredura-cabeça (ver Figura 1B). Soltar a verificação da cabeça de bloqueio bola grampo comum (Figura 1B) e manipular a orientação do transdutor de modo a que ele está alinhado paralelo ao eixo da agulha. Fixe a digitalizaçãoposição da cabeça, apertando a varredura-cabeça bola bloqueio braçadeira conjunta. NOTA: Para injeção em ratos adultos, uma agulha G 30 com a 1 in / 2,5 cm de comprimento é o ideal. Uma seringa de 1 ml podem ser usados ​​para volumes maiores, enquanto que uma seringa estanque ao gás pode ser utilizado para um controlo mais preciso de volumes mais pequenos (5-10 ul). </li><li> Aplicar gel de ultra-som para liberalmente a ponta do transdutor com uma espátula para cobrir a cabeça ao longo da sua totalidade. Desembainhar cuidadosamente a agulha e usar a montagem de agulha controlo para avançar a agulha directamente sob o transdutor e dentro do gel de ultra-som para a visualização. Faça ajustamentos menores, utilizando o controlo de montagem da agulha de modo que a agulha é claramente visualizada ao longo do seu comprimento a imagem de ultra-som em. Se o transdutor foi devidamente alinhado paralelamente à agulha na etapa 1.4, em seguida, a agulha deve permanecer no interior do plano da imagem, uma vez que é avançado e retirado com o botão de controlo de injecção (Figura 1C). </li><li> Em etapas subsequentes, não perturbe a necessidadele / transdutor alinhamento horizontal pelo movimento no eixo horizontal. Em vez disso, partes específicas do coração por injecção, alterando a posição vertical (eixo y) de montagem da agulha e pelo movimento da plataforma de animais. </li><li> Mover o transdutor superiormente a partir da plataforma de animal utilizando a verificação de controlo de altura (Figura 1B) para permitir a subsequente colocação do rato anestesiado para a plataforma animal. Isto não vai perturbar o alinhamento do eixo x do transdutor ao longo do eixo da agulha. </li><li> Retirar a seringa que foi usado para o alinhamento do grampo seringa e descartar cuidadosamente. Carregar a nova agulha e seringa com o injectado para o volume de destino final, permitindo espaço morto na ponta da seringa. Tenha cuidado para remover as bolhas de ar. Colocar a seringa no encaixe da seringa, sem ajustar o alinhamento do eixo-x. Totalmente retirar a seringa usando o controle de injeção. NOTA: Para fins de formação inicial, o uso do azul de Evancorante (1%), corante azul de tripano (0,4%) ou uma suspensão de microesferas fluorescentes como o injectado pode ajudar o operador a confirmação de competência e sucesso de injecção direccionada. </li></ol> 2 Injeção <ol><li> Ligue o aquecedor integrado da plataforma de aquecimento e configurá-lo para 37 ° C. Coloque a plataforma animais 180 ° em relação à orientação normal de imagem, com a braçadeira de mangueira de anestesia e da cabeça do animal, mais próxima do operador. Isto permite que o coração (no lado esquerdo do peito) ser ipsilateral à braçadeira de seringa e agulha. Nota: menor no sentido horário ajustes adicionais para rotação da plataforma de animal pode ser necessário para orientar correctamente o coração para o plano da imagem do eixo curto para-esternal, que será utilizado para a injecção (Figura 2A). </li><li> Prepare camundongos para ecocardiografia conforme relatado anteriormente 9. Anestesiar o mouse em uma câmara de indução com isoflurano a 2%. Remover pêlos no peito com Creme Depilatório umd aplicar gel lubrificante para ambos os olhos para evitar a secagem da esclera. </li><li> Elevar o transdutor usando o scan de controle da altura da cabeça (Figura 1B). Colocar o rato anestesiado supina sobre a plataforma de animais aquecidos com o focinho dentro de um cone de nariz entregar 1-3% de isoflurano (Figuras 2A-2B). Insira cuidadosamente a sonda retal e cole as quatro patas para os eletrodos de ECG, aplicando gel eletrodo para contato elétrico. NOTA: deve ser assegurado um nível adequado de anestesia para o tratamento humano do animal. Não deve haver nenhuma mudança na taxa de coração e não há resposta para a colocação da agulha através da parede torácica. Controles homeostáticos temperatura integrados da plataforma animal deve ser usado para manutenção da temperatura (37 ± 0,5 ° C), enquanto a hipotermia irá resultar em bradicardia relativa, dilatação ventricular, e possível desconforto. </li><li> Uma vez que o mouse está seguro sobre a plataforma animal, reduzir o transdutor na depilapeito ted usando o scan de controle da altura da cabeça (Figura 1B). A configuração ultra-som ideal para injeção é para o coração para ser visualizado na orientação do eixo curto paraesternal, conforme técnica ecocardiográfica padrão. Gire a plataforma animais de 20-30 ° no sentido horário para obter a janela acústica ideal para a injeção na imagem avião eixo curto (Figuras 2A-2B). Nota: Em alternativa, a injecção pode ser realizada a partir de uma orientação paresternal longo do eixo de rotação no sentido anti-horário da plataforma do animal (Figura 2C). </li><li> Use os animais controles para ajuste de plataforma para ajustar o campo de visão e atingir qualquer local da injeção desejada no miocárdio ventricular esquerdo. Pan vai-e-vem do ápice para a base do coração para atingir o local desejado injeção no miocárdio do ventrículo esquerdo (Figuras 3A-3C). Nota: O midpapillary parasternal vista-eixo curto (Figura 3A) oferece reproducible marcos que permitem acompanhamento de imagens do local da injeção. Observação: Como alternativa, o paraesternal longo eixo pode ser utilizado para atingir um local de injecção pré-definido (Figura 3D). </li><li> Começando com a seringa na braçadeira seringa totalmente retraída, mova lentamente a seringa contra o peito do animal, girando os ponteiros do relógio de controle de injeção (Figura 4A). Para permitir a visualização de ultra-som claro de ambos, o coração ea ponta da agulha que se aproxima do peito, use bastante gel de ultra-som sobre o lado esquerdo do peito e otimizar a janela acústica, estabelecendo um amplo campo de visão sobre os controles de ecocardiografia. Defina o ponto / zona focal no local de destino para a injecção. Pequenos ajustes para a agulha montar controles podem otimizar a imagem da agulha ao longo de seu comprimento. NOTA: Algumas máquinas de ultra-som tem uma função de software de guia de agulha para estender digitalmente uma linha ao longo do eixo longitudinal da agulha para a parte alvo miocárdio(Figura 4B). Tal ferramenta de software pode ser útil, mas não é essencial. </li><li> Com o animal adequadamente sedados (1-3% de isoflurano misturada com 0,5-0,8 L / min 100% de oxigénio), o avanço da agulha através da parede torácica do rato e no miocárdio, observando-se cuidadosamente a posição da ponta da agulha biselada em tudo vezes. Parar o avanço quando a ponta da agulha está no interior do miocárdio alvo (Figura 4C). Toda a ponta chanfrada deve ser firmemente dentro do miocárdio, para evitar a fuga de produto de injecção para dentro do espaço pericárdico. </li><li> Quando a ponta fica no local desejado, fornecer o produto de injecção, empurrando o êmbolo da seringa. Entregar o injectado lentamente, durante 5-30 segundos (dependendo do volume a ser entregue). Até 50 ul de produto de injecção podem ser apresentadas, sem comprometer a função ventricular. Um aspecto echobright transitória para a região do miocárdio injectado pode ser evidentes após a injecção com sucesso. Uma breve (segundos) período de relativa bradycardia ocasionalmente é observado com injeção no miocárdio e resolve rapidamente. </li><li> Uma vez que o material injetado foi administrado, prontamente retirar a agulha por rotação anti-horária do botão de controle de injeção. O mouse deve ser mantido sob anestesia por alguns minutos de observação ecocardiograma para confirmar função ventricular preservada e sem complicações pós-procedimento. Se indicado, várias regiões do miocárdio pode ser injectada em série com o reposicionamento do ângulo da agulha de abordagem por ajustamento da plataforma animal. Após a injeção intramiocárdica, o rato é colocado em uma gaiola por conta própria e autorizada a recuperar da anestesia sob observação. </li><li> Não deixe um animal sem supervisão até que ele recuperou a consciência suficiente para manter decúbito esternal. Não devolva um animal que passou por injeção intramiocárdica para a companhia de outros animais até que esteja totalmente recuperado. A gaiola deve ser colocada sobre uma almofada termorregulado com represtação ady de água e rato dieta. Desconforto pós-procedimento não se espera e falta de retomar de forma adequada o comportamento normal logo após a intervenção sugere uma complicação potencial (ver Discussão). </li><li> Cuidadosamente descarte a agulha imediatamente após a conclusão da injeção transmural de minimizar o risco de acidentes com perfurocortantes para o operador ou às pessoas presentes. Reutilizar uma agulha pode resultar em embotamento da ponta tornando-o mais difícil de furar o miocárdio, resultando em um maior risco de complicação. </li></ol>

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The authors have nothing to disclose.

Biológicos podem ser entregues ao miocárdio por injecção directa intramiocárdica, injeção intrapericárdica, ou administração indireta através da corrente sanguínea. Com base em células ensaios de terapia recentes em modelos de infarto do miocárdio têm descrito uma abordagem toracotomia aberta para a entrega do material injetado 12-14. Um fator importante para o sucesso de uma intervenção terapêutica do miocárdio depende da escolha da via de parto. A dose mais elevada do local biológico é ...

A doença cardíaca é a principal causa de morte para homens e mulheres nos Estados Unidos, sendo responsável por 600 mil mortes por ano 1. Modelos murino de doença cardiovascular são extremamente importantes para a investigação de mecanismos fisiopatológicos e para explorar potenciais terapias. Entrega do Miocárdio de vetores de terapia genética, células-tronco, RNAs modificados e outros agentes terapêuticos permite a investigação de seu potencial terapêutico para doenças do coração 2-7. Atualmente, há poucas opções para entrega do miocárdio de agentes terapêuticos em modelos de ratos 6. A injeção transmural sob visualização directa é comumente utilizada, mas requer uma esternotomia ou toracotomia e é limitada à região exposta do coração. Embora conveniente quando realizada no momento de uma outra manipulação experimental tal como LAD ligadura, a necessidade de um procedimento invasivo para entrega intramiocárdicas limita potenciais modelos experimentais e introduz umADICIONAIS efeitos do procedimento (por exemplo, fibrose devido a toracotomia). Entrega de pericárdio percutânea de vetores virais tem sido relatada, mas o local e distribuição de agente terapêutico não é homogênea e é difícil de controlar 8. Percutâneas resultados injeção coronárias em distribuição mais homogênea do material injetado, mas a entrega coronária eficaz e reprodutível, é um desafio em modelos murinos. Aqui, descrevemos um baú técnica de injeção intramiocárdica fechado que permite minimamente invasivo, controlado pelo operador orientação dos agentes terapêuticos sob a orientação do ultra-som. A técnica é fácil de aprender, elimina a necessidade de toracotomia ou esternotomia e suas complicações experimentais de atendimento, e proporciona uma maior flexibilidade do calendário e locais de injeção transmural. Assim, a injecção assistida por ecocardiografia intramiocárdicas representa um método tecnicamente simples e altamente eficaz de manipular omiocárdio em modelos experimentais 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

Modelos murino de doença cardiovascular são importantes para a investigação de mecanismos fisiopatológicos e explorar potenciais terapias regenerativas. Experimentos envolvendo injeção do miocárdio são actualmente desempenhadas pelo acesso cirúrgico direto através de uma toracotomia. Enquanto conveniente quando realizada no momento de outra manipulação experimental, como a ligadura coronária, a necessidade de um procedimento invasivo para entrega intramiocárdica limita potenciais projetos experimentais. Com cada vez melhor resolução ultra-som e modalidades avançadas de imagem não invasivos, é agora possível realizar rotineiramente guiada por ultra-som, injeção intramiocárdica percutânea. Esta modalidade de forma eficiente e confiável fornece agentes para uma região alvo de miocárdio. As vantagens dessa técnica incluem a prevenção de morbidade cirúrgica, a facilidade de atingir regiões do miocárdio seletivamente sob a orientação do ultra-som, bem como a oportunidade para entregar injetado ao myocardium em vários intervalos de tempo predeterminados,. Com a técnica praticada, complicações da injeção transmural são raros, e os ratos rapidamente retornar à atividade normal na recuperação da anestesia. Seguindo os passos descritos neste protocolo, o operador com experiência básica ecocardiografia pode rapidamente tornar-se competente nessa técnica versátil, minimamente invasiva.

A injeção transmural Murino com corante azul ou microesferas fluorescentes A injecção de corante azul de Evan é útil para fins de treino. Logo após a injecção, o rato eutanásia e remover o coração para visualizar a localização do corante azul injectada. Figura 5 mostra um exemplo de uma injecção com sucesso, com o corante azul infiltrantes do miocárdio ao nível dos músculos papilares meados (Figura 5A, região delimitada pela linha a tracejad...

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

Ultrasound-guided Transthoracic Intramyocardial Injection in Mice

Injeção intramiocárdica percutânea guiada por ecocardiografia representa uma modalidade eficiente, confiável e targetable para a entrega de agentes de transferência de genes ou células no coração murino. Seguindo os passos descritos neste protocolo, o operador pode rapidamente tornar-se competente nessa técnica versátil, minimamente invasiva.

Guiada por ultra-som transtorácica intramiocárdico Injection em Ratos

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 visualizações.  Boston Children's Hospital.  Injeção intramiocárdica percutânea guiada por ecocardiografia representa uma modalidade eficiente, confiável e targetable para a entrega de agentes de transferência de genes ou células no coração murino. Seguindo os passos descritos neste protocolo, o operador pode rapidamente tornar-se competente nessa técnica versátil, minimamente invasiva. 

Vídeo: 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.

Ecocardiografia transtorácica em Ratos

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

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 da artéria coronária e injeção intramiocárdica em um 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.

Entrega celular intramiocárdico: Observações em murino Corações

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).

Substernal Tireóide Biópsia Usando endobrônquica guiada por ultrassom transbrônquica Punção Aspirativa por Agulha

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.

O ultra-som-guiada botulínica injeções de toxina-A: um método de tratamento Sialorréia

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.

Guiada por ultra-som intracardíaca injeção de células-tronco mesenquimais humanas para aumentar Homing para o intestino para uso em modelos murino de doenças intestinais inflamatórias Experimental

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.

Injeção de contraste percutânea guiada por ecocardiografia Intramiocárdica e entrega de célula em uma grande maquete pré-clínicos

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.

Exame ecocardiográfico transtorácico no modelo coelho

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.

Drenagem biliar guiada por ultrassom endoscópico: Hepaticogastrostomia Guiada por Ultrassom Endoscópico em Obstrução 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.

Implante de Cardiomiócitos Derivados de Células-Tronco Pluripotentes Induzidos por Ultrassom em Camundongos Infartados do Miocárdio

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