Los autores desean agradecer a John Marston para el experto la cría de animales y el Dr. Marco A. Passini para la asistencia técnica en las primeras etapas de este proyecto. Este trabajo fue financiado por la beca de los Institutos Nacionales de Salud para la LLC (R01NS41584; R01HD054413).

1. Inyección intracerebroventricular <ol><li> El primer paso es la preparación de las soluciones de inyección de valores, estas soluciones son vector viral, el ADN plásmido, las drogas, y debe ser inyectado bajo condiciones estériles. </li><li> Mezcla de un título deseado de vector viral (total l 5-7) con un 0,05% w / v de azul tripan en PBS durante la visualización del sitio de la inyección. </li><li> Solución de ADN plásmido (5 en total l l) contiene D-(+)-glucosa al 20% (w / v) (1 l), azul de tripano (0,05%) PBS (1 l), el plásmido (~ 5 ~ g / L ~ ) (2 ~ L), y 2,5 kDa homopolímero lineal PEI (150 mm) (1 ~ L). </li><li> Inmovilizar el PND dos recién nacidos a través de la crio-anestesia durante 1-2 minutos. </li><li> La aguja utilizada para la inyección es un micro-litros calibrada micropipeta de vidrio esterilizado que se adjunta a una jeringa de 3 ml 3 ml Hamilton a través de un tubo largo. </li><li> Romper la punta de la aguja (con una espátula) para ajustarse a la penetración de 2 mm en el cráneo. Colocar la aguja en diagonal en el tubo de microcentrífuga que contiene la solución inyectable. Cargue la solución de la inyección en la aguja con cuidado tirando del émbolo de la jeringa. </li><li> Después de la absorción de la solución, desvincular la jeringa de la sonda, tire del émbolo hasta allá y luego se adhieren a la aguja de nuevo. </li><li> Mantenga la aguja en la mano derecha entre el pulgar y los dedos índice y coloque la jeringa entre los dedos medio y anular con el émbolo tocando la palma de la mano derecha. </li><li> Sujete firmemente el ratón inmovilizado por la piel detrás de la cabeza con la mano izquierda y colocar en una luz de fibra óptica para iluminar las estructuras anatómicas relevantes que se pueden utilizar como guía. </li><li> Inserte la aguja de 2 mm de profundidad, perpendicular a la superficie del cráneo, en un lugar de aproximadamente 0,25 mm lateral a la sutura sagital y 0,50-0,75 mm rostral a la sutura coronaria neonatal (Figura 1). A continuación, empuje el émbolo con la palma de la la mano derecha muy despacio y con cuidado. Monitor de ruptura de vasos o hinchazón de la cara. </li><li> Retire la aguja de 15 segundos después de la interrupción del movimiento del émbolo para evitar el reflujo. </li><li> Para recuperar, mantener a los ratones durante 5-10 minutos en un recipiente calentado hasta que el movimiento y la respuesta general es restaurado. </li></ol> 2. La inyección intravenosa a través de la vena temporal / facial <ol><li> La solución a inyectar debe estar preparado y que será completada con el tinte filtra los alimentos verdes en dilución 1:100 y se inyecta bajo condiciones estériles. </li><li> Adjuntar una pequeña de plástico luer hasta el final de una jeringa de vidrio de 100 L Hamilton. Para el luer, conectar un 33 calibre 0,25 pulgadas aguja hipodérmica. Asegúrese de que todas las piezas estén bien conectados. </li><li> Cargue la jeringa con el volumen a inyectar, asegurando que no hay aire en la jeringa como la inyección de aire en el vaso es letal. A menudo es útil para pipeta el volumen que se inyecta a un trozo de parafilm. Esto permite la visualización clara de la absorción de la solución en la jeringa. </li><li> A la vista Transiluminador Wee se utiliza para visualizar fácilmente la vena temporal superficial, o en la vena facial, en el neonato (Figura 2A). Antes de la inyección, seguro del recién nacido a la transiluminador con cinta quirúrgica. Gasa se debe colocar entre el recién nacido y la cinta para evitar que la cinta de dañar la piel del animal. Seguro que el animal el transiluminador de su lado, asegurando que la cinta no impide la respiración. El cuello del recién nacido debe ser agitado giró de forma que la vena facial es fácilmente visible y la nariz debe ser grabada para estabilizar la cabeza. </li><li> Usando una lupa diadema 2,25 X para permitir una mejor visualización, introduzca lentamente la aguja en la vena. La vena es muy superficial por lo que la aguja debe permanecer visible debajo de la piel. </li><li> Poco a poco infundir el volumen de la solución en la vena. El tinte verde permite una fácil visualización de la inyección. </li><li> Espere 15 segundos antes de retirar la aguja, como hay un desfase entre completamente el émbolo de la jeringa y la expulsión de la solución restante debido a la perforación de aguja extremadamente estrecho. </li><li> Después de retirar la aguja, usar una gasa para aplicar presión en el sitio de la inyección hasta que el sangrado se detiene. </li><li> Monitorear el recién nacido en busca de signos de angustia. Después de una inyección adecuada, no angustia manifiesta deben ser observados. El recién nacido debe ser dado a unos 5 minutos para recuperarse antes de que sea devuelto a la jaula. </li><li> Enjuague la unidad de la aguja / jeringa con PBS entre las inyecciones de la sangre en la aguja rápidamente se obstruyen debido al pequeño diámetro. </li></ol> 3. Los resultados representativos: ICV inyección: El cerebro se puede cosechar en el momento de los diferentes puntos después de la inyección y se visualizan para demostrar la técnica de inyección de éxito. Si el medio no se agrega a la solución de inyección, que será difícil para verificar la exactitud de los deproyección. De inyección adecuada de uno de los ventrículos permite la distribución de los azules en el lado de tripan inyecta en el cerebro a unos 10-15 minutos después de la inyección (fig. 1B). Una distribución uniforme de azul tripán en ambos hemisferios cerebrales derecho e izquierdo y bulbos olfatorios será visible aproximadamente 60 minutos después de la inyección (fig. 1C). Esto se debe a la conectividad de los ventrículos cerebrales que permitan la difusión del colorante azul al ventrículo adyacente. Inyecciones de precisión también puede verse por la dispersión del colorante azul en el canal central de la columna rostral aproximadamente dentro de 12 horas después de la inyección (Figura 1D). Inyecciones incorrectas pueden ser distinguidos por la falta de color azul en los hemisferios cerebrales. En este caso, la profundidad de la aguja no fue suficiente y la solución de inyección probablemente ha distribuido bajo la piel. Una posibilidad alternativa es que la aguja penetra demasiado profundamente en el cerebro, lo que pasa más allá del ventrículo y la solución se vacía por debajo de los ventrículos cerebrales. IV de inyección: inyección precisa y eficiente la vena temporal / facial puede ser visualizado inmediatamente después de la inyección. Como la solución se inyecta el tinte verde permite la visualización de la solución que entra y fluye a través de la vena facial (Figura 2A). Además, el color de la piel alterada del ratón se observó después de la inyección. El recién nacido es de color rosado normal se convierte en verde, debido a la presencia del colorante verde en la solución de la inyección (Figura 2B). La medida del cambio de color verde observada en el recién nacido depende de la concentración de colorante utilizado. Para la visualización simple de la inyección y durante un periodo de prácticas, una dilución 1:50 se recomienda. Sin embargo, el tono de la piel dramáticamente alterado con frecuencia resulta en el cachorro de ser rechazado por la madre y por lo tanto, la eliminación del colorante o una concentración significativa reducción se debe considerar en los procedimientos experimentales. Una inyección incorrecta dará lugar a la acumulación de colorante verde debajo de la piel en el sitio de la inyección. Inyección incompleta, lo que ocurre cuando la abertura de la aguja no está completamente insertada en la vena, se ve cuando los flujos de alguna solución en la vena y algunos se acumula bajo la piel. Si esto se detecta, la aguja debe insertarse aún más en el vaso. <img src="/files/ftp_upload/2968/2968fig1.jpg" alt="Figura 1"/> Figura 1. Demostración del éxito de las inyecciones de ICV en PDN2 ratones. Un esquema) de los sitios de inyección utilizado en las inyecciones ICV hacia los ventrículos. B) del cerebro de ICV inyecta Cachorro con azul tripán en PBS el ventrículo izquierdo, foto tomada 15 minutos después de la inyección. C ) del cerebro de ICV inyecta Cachorro con azul tripán en PBS en ventrículo izquierdo, foto tomada 60 minutos después de la inyección. D) se muestra el centro del canal espinal rostral de ICV inyecta cachorro con azul tripán en PBS el ventrículo izquierdo, foto tomada 12 horas después de la inyección. <img src="/files/ftp_upload/2968/2968fig2.jpg" alt="Figura 2"/> Figura 2. Demostración del éxito de inyecciones intravenosas en PDN2 ratones. Esquema A) de la vena facial utilizada para inyecciones intravenosas. B) IV Cachorro inyectó un tinte verde en comparación con PBS sin inyección de la misma camada, foto tomada inmediatamente después de la inyección.

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No hay conflictos de interés declarado.

Investigación utilizando modelos de ratón de la enfermedad a menudo requiere la administración de medicamentos u otras sustancias a los recién nacidos. En este video, se demuestra el paso a paso los procedimientos que participan dos tipos de estrategias de inyección que puede ser utilizada para combatir el SNC: 1) la inyección directa en el sistema nervioso central que utilizan intracerebroventricular (ICV) de la inyección, o 2) la inyección IV dirigidas a la / temporal vena facial. El calendario de estas inyecc...

<table border="1"><tbody><tr><th> Nombre del reactivo </th><th> Empresa </th><th> Número de catálogo </th><th> Comentarios (opcional) </th></tr><tr><td> Verde colorantes en los alimentos </td><td> McCormick </td><td> n / a </td><td> Debe ser filtrada </td></tr><tr><td> Hamilton jeringa de vidrio (100 l) </td><td> Sigma Aldrick </td><td> 20702 </td><td></td></tr><tr><td> Tema LuerMxF White Style Nylon </td><td> Piezas pequeñas, Inc. </td><td> VPLF-LC78-1-25 </td><td></td></tr><tr><td> Finas agujas hipodérmicas calibre </td><td> Corchete </td><td> 7111 </td><td> Tamaño: 33 (SWG) x ¼ &quot;(6,35 mm) </td></tr><tr><td> Transiluminador vista Wee </td><td> Respironics </td><td> 1017920 </td><td></td></tr><tr><td> 2,25 X diadema Lupa </td><td> MagEyes </td><td> Modelo N º 5 </td><td> Seleccione ampliación para adaptarse a las preferencias individuales </td></tr></tbody></table>

delivery of therapeutic agents through intracerebroventricular (icv) and intravenous (iv) injection in mice

A pesar de la función protectora de la barrera hematoencefálica juega en la protección del cerebro, limita el acceso al sistema nervioso central (SNC) que con mayor frecuencia resulta en el fracaso de la terapéutica potencial diseñado para 1,2 trastornos neurodegenerativos. Enfermedades neurodegenerativas como la atrofia muscular espinal (SMA), en el que las neuronas motoras inferiores se ven afectados, pueden beneficiarse enormemente de la introducción de los agentes terapéuticos en el SNC. El propósito de este video es para demostrar dos paradigmas diferentes de inyección para entregar los materiales terapéuticos en ratones recién nacidos poco después del nacimiento. Uno de estos métodos es la inyección directamente en los ventrículos laterales cerebrales (intracerebroventricular) que se traduce en la entrega de materiales en el sistema nervioso central a través del líquido cefalorraquídeo 3,4. El segundo método es una inyección en la vena temporal (intravenosa) que se pueden introducir diferentes terapias en el sistema circulatorio, dando lugar a la entrega sistémica incluyendo los 5 del SNC. Transducción generalizada del sistema nervioso central que se puede lograr si un vector apropiado viral y el serotipo viral se utiliza. La visualización y la utilización de la vena temporal para la inyección es posible hasta después del día 6. Sin embargo, si el material entregado está destinado a llegar al sistema nervioso central, estas inyecciones debe llevarse a cabo mientras la barrera hematoencefálica es más permeable, debido a su estado de inmadurez, de preferencia antes del día 2 después del parto. La barrera sanguínea del cerebro completamente desarrollado en gran medida limita la eficacia de la administración intravenosa. Ambos sistemas de entrega son simples y efectivas una vez que la capacidad quirúrgica se logra. No requieren ningún dispositivo quirúrgico extenso y se puede realizar por una sola persona. Sin embargo, estas técnicas no es una tarea sencilla. El pequeño tamaño de postnatal día 2 cachorros y las áreas posteriores objetivo pequeñas pueden hacer que las inyecciones difícil de realizar y en un principio difícil de replicar.

Watch this Scientific Journal Video about Delivery of Therapeutic Agents Through Intracerebroventricular ICV and Intravenous IV Injection in Mice at JoVE.com

Delivery of Therapeutic Agents Through Intracerebroventricular ICV and Intravenous IV Injection in Mice

Este artículo muestra dos métodos muy diferentes de inyección: 1) en el cerebro (intracerebroventricular) y 2) sistémica (intravenosa) para introducir los agentes terapéuticos en el sistema nervioso central de ratones recién nacidos.

La entrega de los agentes terapéuticos a través de intracerebroventricular (ICV) y la inyección intravenosa (IV) en ratones

Despite the protective role that blood brain barrier plays in shielding the brain, it limits the access to the central nervous system (CNS) which most ...

delivery-therapeutic-agents-through-intracerebroventricular-icv

Research

JoVE Journal

Medicine

Delivery of Therapeutic Agents Through Intracerebroventricular (ICV) and Intravenous (IV) Injection in Mice

58.7K vistas.  University of Missouri. Este artículo muestra dos métodos muy diferentes de inyección: 1) en el cerebro (intracerebroventricular) y 2) sistémica (intravenosa) para introducir los agentes terapéuticos en el sistema nervioso central de ratones recién nacidos.

Video: Delivery of Therapeutic Agents Through Intracerebroventricular ICV and Intravenous IV Injection in Mice

Orthotopic Xenografting of Human Luciferase-Tagged Malignant Peripheral Nerve Sheath Tumor Cells for in vivo Testing of Candidate Therapeutic Agents

Although in vitro screens are essential for the initial identification of candidate therapeutic agents, a rigorous assessment of the drug's ability to inhibit tumor growth must be performed in a suitable animal model. The type of animal model that is best for this purpose is a topic of intense discussion. Some evidence indicates that preclinical trials examining drug effects on tumors arising in transgenic mice are more predictive of clinical outcome1and so candidate therapeutic agents are often tested in these models. Unfortunately, transgenic models are not available for many tumor types. Further, transgenic models often have other limitations such as concerns as to how well the mouse tumor models its human counterpart, incomplete penetrance of the tumor phenotype and an inability to predict when tumors will develop.
Consequently, many investigators use xenograft models (human tumor cells grafted into immunodeficient mice) for preclinical trials if appropriate transgenic tumor models are not available. Even if transgenic models are available, they are often partnered with xenograft models as the latter facilitate rapid determination of therapeutic ranges. Further, this partnership allows a comparison of the effectiveness of the agent in transgenic tumors and genuine human tumor cells. Historically, xenografting has often been performed by injecting tumor cells subcutaneously (ectopic xenografts). This technique is rapid and reproducible, relatively inexpensive and allows continuous quantitation of tumor growth during the therapeutic period2. However, the subcutaneous space is not the normal microenvironment for most neoplasms and so results obtained with ectopic xenografting can be misleading due to factors such as an absence of organ-specific expression of host tissue and tumor genes. It has thus been strongly recommended that ectopic grafting studies be replaced or complemented by studies in which human tumor cells are grafted into their tissue of origin (orthotopic xenografting)2. Unfortunately, implementation of this recommendation is often thwarted by the fact that orthotopic xenografting methodologies have not yet been developed for many tumor types.
Malignant peripheral nerve sheath tumors (MPNSTs) are highly aggressive sarcomas that occur sporadically or in association with neurofibromatosis type 13and most commonly arise in the sciatic nerve4. Here we describe a technically straightforward method in which firefly luciferase-tagged human MPNST cells are orthopically xenografted into the sciatic nerve of immunodeficient mice. Our approach to assessing the success of the grafting procedure in individual animals and subsequent non-biased randomization into study groups is also discussed.

Orthotopic Xenografting of Human Luciferase-Tagged Malignant Peripheral Nerve Sheath Tumor Cells for in vivo Testing of Candidate Therapeutic Agents

A method for reliably grafting luciferase-tagged human malignant peripheral nerve sheath tumor cells into the sciatic nerve of immunodeficient mice is described. The use of bioluminescence imaging to demonstrate proper establishment of tumor grafts and criteria for random segregation of animals into study groups are also discussed.

Xenotrasplante ortotópico de los Derechos Humanos-luciferasa Tagged células malignas del tumor vaina de nervio periférico para In vivo Pruebas de candidatos a agentes terapéuticos

Although in vitro screens are essential for the initial identification of candidate therapeutic agents, a rigorous assessment of the drug's ability to ...

Investigación

Medicina

Slow-release Drug Delivery through Elvax 40W to the Rat Retina: Implications for the Treatment of Chronic Conditions

Diseases of the retina are difficult to treat as the retina lies deep within the eye. Invasive methods of drug delivery are often needed to treat these diseases. Chronic retinal diseases such as retinal oedema or neovascularization usually require multiple intraocular injections to effectively treat the condition. However, the risks associated with these injections increase with repeated delivery of the drug. Therefore, alternative delivery methods need to be established in order to minimize the risks of reinjection. Several other investigations have developed methods to deliver drugs over extended time, through materials capable of releasing chemicals slowly into the eye. In this investigation, we outline the use of Elvax 40W, a copolymer resin, to act as a vehicle for drug delivery to the adult rat retina. The resin is made and loaded with the drug. The drug-resin complex is then implanted into the vitreous cavity, where it will slowly release the drug over time. This method was tested using 2-amino-4-phosphonobutyrate (APB), a glutamate analogue that blocks the light response of the retina. It was demonstrated that the APB was slowly released from the resin, and was able to block the retinal response by 7 days after implantation. This indicates that slow-release drug delivery using this copolymer resin is effective for treating the retina, and could be used therapeutically with further testing.

This paper details how Elvax 40W can be used as a slow-release method for drug delivery to the adult rat retina. The protocol for preparing, loading, and delivering the drug-resin complex to the eye is described.

De liberación lenta Drug Delivery través Elvax 40W a la Rata Retina: Implicaciones para el tratamiento de condiciones crónicas

Diseases of the retina are difficult to treat as the retina lies deep within the eye. Invasive methods of drug delivery are often needed to treat these ...

Ultrasound-guided Transthoracic Intramyocardial Injection in Mice

Murine models of cardiovascular disease are important for investigating pathophysiological mechanisms and exploring potential regenerative therapies. Experiments involving myocardial injection are currently performed by direct surgical access through a thoracotomy. While convenient when performed at the time of another experimental manipulation such as coronary artery ligation, the need for an invasive procedure for intramyocardial delivery limits potential experimental designs. With ever improving ultrasound resolution and advanced noninvasive imaging modalities, it is now feasible to routinely perform ultrasound-guided, percutaneous intramyocardial injection. This modality efficiently and reliably delivers agents to a targeted region of myocardium. Advantages of this technique include the avoidance of surgical morbidity, the facility to target regions of myocardium selectively under ultrasound guidance, and the opportunity to deliver injectate to the myocardium at multiple, predetermined time intervals. With practiced technique, complications from intramyocardial injection are rare, and mice quickly return to normal activity on recovery from anesthetic. Following the steps outlined in this protocol, the operator with basic echocardiography experience can quickly become competent in this versatile, minimally invasive technique.

Echocardiography-guided percutaneous intramyocardial injection represents an efficient, reliable, and targetable modality for the delivery of gene transfer agents or cells into the murine heart. Following the steps outlined in this protocol, the operator can quickly become competent in this versatile, minimally invasive technique.

Guiada por ecografía transtorácica intramiocárdica inyección en ratones

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

Testing the Efficacy of Pharmacological Agents in a Pericardial Target Delivery Model in the Swine

To date, many pharmacological agents used to treat or prevent arrhythmias in open-heart cases create undesired systemic side effects. For example, antiarrhythmic drugs administered intravenously can produce drops in systemic pressure in the already compromised cardiac patient. While performing open-heart procedures, surgeons will often either create a small port or form a pericardial cradle to create suitable fields for operation. This access yields opportunities for target pharmacological delivery (antiarrhythmic or ischemic preconditioning agents) directly to the myocardial tissue without undesired side effects.
We have developed a swine model for testing pharmacological agents for target delivery within the pericardial fluid. While fully anesthetized, each animal was instrumented with a Swan-Ganz catheter as well as left and right ventricle pressure catheters, and pacing leads were placed in the right atrial appendage and the right ventricle. A medial sternotomy was then performed and a pericardial access cradle was created; a plunge pacing lead was placed in the left atrial appendage and a bipolar pacing lead was placed in the left ventricle. Utilizing a programmer and a cardiac mapping system, the refractory period of the atrioventricular node (AVN), atria and ventricles was determined. In addition, atrial fibrillation (AF) induction was produced utilizing a Grass stimulator and time in AF was observed. These measurements were performed prior to treatment, as well as 30 min&#160;and 60 min&#160;after pericardial treatment. Additional time points were added for selected studies. The heart was then cardiopleged and reanimated in a four chamber working mode. Pressure measurements and function were recorded for 1 hr after reanimation. This treatment strategy model allowed us to observe the effects of pharmacological agents that may decrease the incidence of cardiac arrhythmias and/or ischemic damage, during and after open-heart surgery.

We have developed a swine model for the target delivery of pharmacological agents within the pericardial space/fluid. Using this approach, the relative benefits of administered agents on induced atrial fibrillation, relative refractory periods and/or ischemic protection can be investigated.

Prueba de la eficacia de los agentes farmacológicos en un modelo de entrega de destino pericárdico en la producción porcina

To date, many pharmacological agents used to treat or prevent arrhythmias in open-heart cases create undesired systemic side effects. For example, ...

Disposable Dosators for Pulmonary Insufflation of Therapeutic Agents to Small Animals

Development of new therapeutic products requires efficacy testing in an animal model. The pulmonary route of administration can be utilized to deliver drugs locally and systemically. Evaluation of dry powder aerosols necessitates an efficient dispersion mechanism to maintain high concentrations in an exposure chamber or for direct endotracheal administration. While solutions exist to expose animals by passive inhalation to dry powder aerosols, most require masses of powder in large excess of the dose delivered. This precludes conducting early feasibility studies as insufficient drug is available at the research or early development stage to support the dose delivery requirements for conventional aerosol delivery systems. When designing an aerosol drug product, aerodynamic performance can relate directly to delivery efficiency and efficacy. Dispersion of powder into an aerosol requires energy input sufficient to overcome interparticulate forces, and particle engineering approaches can substantially improve aerosol performance. We have developed a dispersion system (dosator) which can aerosolize engineered dry powder aerosols efficiently for the purpose of direct pulmonary insufflation, dispersion into an exposure system or generation for analytical purposes.

During development of drugs for pulmonary delivery, it is necessary to evaluate pharmacokinetics and efficacy in an animal model. We present a method to build a disposable aerosol dispersion system from of-the-shelf components that can be used to administer intrapulmonary dry powder aerosol to rodents.

Dosificadores desechable para insuflación pulmonar de agentes terapéuticos para animales pequeños

Development of new therapeutic products requires efficacy testing in an animal model. The pulmonary route of administration can be utilized to deliver ...

Intranasal Delivery of Therapeutic Stem Cells to Glioblastoma in a Mouse Model

The intrinsic tropism towards brain malignancies renders stem cells as promising carriers of therapeutic agents against malignant tumors. The delivery of therapeutic stem cells via the intranasal route is a recently discovered alternative strategy, with strong potential for clinical translation, due to its non-invasive nature compared to intracranial implantation or delivery via systemic routes. The lack of blood brain barrier further strengthens the therapeutic potential of stem cells undergoing intranasal brain entry. This article summarizes the essential techniques utilized in our studies and outlines the basic principles of intranasal strategy for stem cell delivery using a mouse model of intracranial glioma xenografts. We demonstrate the optimized procedures that generate consistent and reproducible results with specific predetermined experimental parameters and offer guidelines for streamlined work flow that ensure efficient execution and reliable experimental outcome. The article is designed to serve as a baseline for further experimental customization based on hypothesis, stem cell types, or tumor specifics.

Stem cells are promising therapeutic carriers to treat brain tumors due to their intrinsic tumor tropism. Non-invasive intranasal stem cell delivery bypasses the blood brain barrier and demonstrates strong potential for clinical translation. This article summarizes the basic principles of intranasal stem cell delivery in a mouse model of glioma.

Entrega intranasal de células madre terapéuticas a glioblastoma en un modelo de ratón

The intrinsic tropism towards brain malignancies renders stem cells as promising carriers of therapeutic agents against malignant tumors. The delivery of ...

A Rat Carotid Artery Pressure-Controlled Segmental Balloon Injury with Periadventitial Therapeutic Application

Cardiovascular disease remains the leading cause of death and disability worldwide, in part due to atherosclerosis. Atherosclerotic plaque narrows the luminal surface area in arteries thereby reducing adequate blood flow to organs and distal tissues. Clinically, revascularization procedures such as balloon angioplasty with or without stent placement aim to restore blood flow. Although these procedures reestablish blood flow by reducing plaque burden, they damage the vessel wall, which initiates the arterial healing response. The prolonged healing response causes arterial restenosis, or re-narrowing, ultimately limiting the long-term success of these revascularization procedures. Therefore, preclinical animal models are integral for analyzing the pathophysiological mechanisms driving restenosis, and provide the opportunity to test novel therapeutic strategies. Murine models are cheaper and easier to operate on than large animal models. Balloon or wire injury are the two commonly accepted injury modalities used in murine models. Balloon injury models in particular mimic the clinical angioplasty procedure and cause adequate damage to the artery for the development of restenosis. Herein we describe the surgical details for performing and histologically analyzing the modified, pressure-controlled rat carotid artery balloon injury model. Additionally, this protocol highlights how local periadventitial application of therapeutics can be used to inhibit neointimal hyperplasia. Lastly, we present light sheet fluorescence microscopy as a novel approach for imaging and visualizing the arterial injury in three-dimensions.

The rat carotid artery balloon injury mimics the clinical angioplasty procedure performed to restore blood flow in atherosclerotic vessels. This model induces the arterial injury response by distending the arterial wall, and denuding the intimal layer of endothelial cells, ultimately causing remodeling and an intimal hyperplastic response.

Una lesión de globo segmentario controlada por presión arterial carótida de rata con aplicación terapéutica periavential

Cardiovascular disease remains the leading cause of death and disability worldwide, in part due to atherosclerosis. Atherosclerotic plaque narrows the ...

Intratracheal Administration of Dry Powder Formulation in Mice

In the development of inhalable dry powder formulations, it is essential to evaluate their biological activities in preclinical animal models. This paper introduces a noninvasive method of intratracheal delivery of dry powder formulation in mice. A dry powder loading device that consists of a 200 &#181;L gel loading pipette tip connected to an 1 mL syringe via a three-way stopcock is presented. A small amount of dry powder (1-2 mg) is loaded into the pipette tip and dispersed by 0.6 mL of air in the syringe. Because pipette tips are disposable and inexpensive, different dry powder formulations can be loaded into different tips in advance. Various formulations can be evaluated in the same animal experiment without device cleaning and dose refilling, thereby saving time and eliminating the risk of cross-contamination from residual powder. The extent of powder dispersion can be inspected by the amount of powder remaining in the pipette tip. A protocol of intubation in mouse with a custom-made light source and a guiding cannula is included. Proper intubation is one of the key factors that influences the intratracheal delivery of dry powder formulation to the deep lung region of the mouse.

Dry powder formulations for inhalation have great potential in treating respiratory diseases. Before entering human studies, it is necessary to evaluate the efficacy of the dry powder formulation in preclinical studies. A simple and noninvasive method of the administration of dry powder in mice through the intratracheal route is presented.

Administración Intratraqueal De La Formulación De Polvo Seco En Ratones

In the development of inhalable dry powder formulations, it is essential to evaluate their biological activities in preclinical animal models. This paper ...

Decocción de Liujunzi: Un tratamiento eficaz para la prevención del CCU-CRC

Establishment of Coloproctitis Cancer Model in Mice and Evaluation of Therapeutic Effect of Chinese Medicine

Colorectal cancer (CRC) is a common malignancy of the digestive system and has become the third most common malignancy worldwide and the second leading cause of malignancy-related death. Ulcerative coloproctitis (UC) is a precancerous lesion, and UC-associated CRC (UC-CRC) is the most common subtype of CRC. Therefore, a reasonable UC-CRC model is the cornerstone and guarantee of new drug development. Traditional Chinese medicine (TCM) has been widely used in the treatment of UC-CRC due to its good efficacy. As a classic tonic prescription of TCM, Liujunzi decoction (LJZD) has been widely used in the treatment of UC-CRC. In this study, a UC-CRC model was established by combining azomethane and dextran sulfate sodium, and the LJZD was administered. The data confirmed that LJZD can effectively inhibit cancer transition in UC-CRC by using mouse body weight, colorectal length, pathological and inflammatory factors, colorectal barrier function, and cancer markers. This protocol provides a system for evaluating the efficacy of TCM in the prevention and treatment of UC-CRC.

Autor destacado: La decocción de Liujunzi como tratamiento tradicional chino para el cáncer de coloproctitis

This protocol provides a mouse model of ulcerative coloproctitis-associated colorectal cancer induced by azomethane combined with dextran sulfate sodium. The model was used to evaluate the efficacy of traditional Chinese medicine compounds in the prevention and treatment of colorectal cancer.

Establecimiento de un modelo de cáncer de coloproctitis en ratones y evaluación del efecto terapéutico de la medicina china

Colorectal cancer (CRC) is a common malignancy of the digestive system and has become the third most common malignancy worldwide and the second leading ...