Este trabajo fue apoyado por los números de concesión de subvenciones y R01HL096593 K23HL72825 del Instituto Nacional del Corazón, los Pulmones y la Sangre. El contenido es responsabilidad exclusiva de la Universidad Thomas Jefferson y no representa necesariamente la opinión oficial del Instituto Nacional del Corazón, los Pulmones y la Sangre o los Institutos Nacionales de Salud.

Presentación de casos (requerido, en su caso): NA, lo que es todavía un procedimiento de investigación experimental, aún no se utilizan clínicamente. Diagnóstico, evaluación y plan (requerido, en su caso): NA, lo que es todavía un procedimiento de investigación experimental, aún no se utilizan clínicamente. Procedimiento (obligatorio): Esta parte debe incluir una descripción paso a paso de los procedimientos pertinentes, cumpliendo con las siguientes pautas. 1. Microscopía capilar (Figura 1) <ol><li> Nuestra técnica es una adaptación de capilaroscopia Serne y sus colegas 1. Un criterio de exclusión para este procedimiento es la enfermedad del colágeno vascular, enfermedad vascular del colágeno ya que produce cambios conocidos capilares 2. </li><li> Después de un mínimo de 10-hr noche de ayuno y 20 min de descanso sentada, las mediciones se llevan a cabo microvasculares durante una media hora entre-7y 11 horas, en una habitación tranquila temperatura, controlada (mantenido entre 21.5-22.5 ° C), con el sujeto en posición sentada y la mano izquierda a la altura del corazón. </li><li> Periungueal capilares en la piel dorsal del tercer dedo se visualizaron utilizando un microscopio estereoscópico (Olympus, Center Valley, PA), vinculado a un Insight megapíxeles 4 SPOT monocromo cámara digital (número de modelo en-1400: instrumentos de diagnóstico, Sterling Heights, MI), y un ordenador portátil (Dell Latitude D600: Dell, Austin, TX). Para limitar el movimiento, la mano y el antebrazo izquierdos están más o menos cubierta con una manta doblada, y reposó en otra manta doblada colocada en la base del microscopio. </li><li> Iluminación lecho ungueal se consigue con una lámpara halógena de 250 W de fibra óptica (KL 2500LCD: Schott-Fostec; Elmsford, NY); iluminación adicional de una fibra suplementaria 150W óptico fuente de luz halógena (B &amp; B Microscopios, Ltd., Warrendale, PA) se utiliza en individuos con pigmentación oscura. </li><li> Para visualizar los capilares, la3.2x objetivo (Olympus 3.2/0.07) se usa con un aumento del sistema total de 38.4x. </li><li> El uso de software de imágenes SPOT proporciona con la cámara, luz / oscuridad de contraste en las fotografías capilares se ve reforzada con la misma función estándar de software SPOT (estiramiento de los niveles de claros y oscuros) para maximizar la visibilidad de los capilares en todas las materias. </li><li> Para cuantificar la densidad capilar, fotomicrografías digitales se toman cada sec 3-5 durante cada una de tres etapas, al inicio del estudio en reposo, durante la hiperemia reactiva postocclusive, y durante la oclusión venosa. (A) Al inicio del descanso, fotomicrografías se toman durante un período de tres minutos para detectar los capilares perfundidos en reposo. (B) durante la hiperemia reactiva postocclusive, se toman fotomicrografías de cuantificar funcionalmente capilares perfundidos (línea de base más capilares reserva), de la siguiente manera. En primer lugar, un manguito de oclusión en la parte superior del brazo izquierdo es inflado a 40 mm Hg por encima de la presión sistólica de 10 min. Las microfotografías son llevados durante ªminutos e inmediatamente después de la liberación primero de la oclusión arterial, visualizando todo funcionalmente perfundidos capilares. Baja densidad capilar tras la hiperemia reactiva indica deterioro reclutamiento capilar funcional, y por lo tanto rarefacción funcional. (C) Durante venosos fotomicrografías de oclusión se toman para cuantificar la densidad máxima capilar, que incluye tanto el perfundido (con celda activa glóbulos rojos (RBC) de movimiento) y nonperfused (lleno de estancamiento, que no se mueven los glóbulos rojos) capilares 3 como sigue. Tras diez minutos de descanso después del procedimiento postocclusive hiperemia reactiva, el brazalete se infla a 60 mm Hg durante 60 segundos, pasivamente forzando la sangre a todos los presentes patente capilares y fotomicrografías fueron tomadas durante este tiempo. Dado que la densidad capilar máxima incluye todo estructuralmente capilares presentes, una reducción en la densidad capilar máxima indica rarefacción estructural. </li><li> La densidad capilar se define como el número de capilares por cuadrado milmilimétricas de la piel del lecho ungueal, y se calcula como la media de cuatro medidas obtenidas de las cuatro imágenes más claramente centradas, al menos distorsionada por el movimiento. En nuestros estudios, los valores típicos para el recuento capilar (capilares / mm 2) han sido 55-80 de línea de base, 65-90 de post-isquémica, y 90-105 de la oclusión venosa. Los valores para el reclutamiento ciento capilar son típicamente entre 5% y 25% (media del ~ 10-15%) y por ciento capilares perfundidos entre 70% y 95% (media del ~ 80-90%), con valores fueron inferiores entre los hipertensos que normotensos. La reproducibilidad del procedimiento de recuento se ha verificado con tres observadores independientes que realizaron las evaluaciones manuales de fotografías de 10 temas diferentes (Figura 2). Los observadores fueron cegados a la identidad y la presión arterial de estos temas. Después del entrenamiento, los recuentos posteriores realizadas de forma independiente demostró un alto nivel de acuerdo. Promedio discrepancias entre calificadores y calificadores intra-eran de la order de 2-3 vasos capilares / mm 2, y los coeficientes de correlación intraclase fueron superiores a 0,90. A corto plazo, la variación de las medidas capilaroscopia eran del mismo orden de magnitud que las discrepancias entre calificadores y calificadores intra-(aproximadamente 2 capilares / mm 2), pero a más largo plazo, la variación observada durante 2-3 años fue un orden de magnitud mayor (aproximadamente 15 capilares / mm 2), lo que indica que los cambios longitudinales se pueden distinguir fácilmente de la variación de calificadores. Fiabilidad de las dos medidas de la función capilar también fue alta (coeficiente de correlación intraclase = 0,84 para el reclutamiento capilar por ciento y 0,82 por ciento para perfusión capilares). </li><li> Los investigadores ahora utilizan un método basado en computadora para cuantificar la densidad capilar utilizando Image-Pro Plus de imágenes de software (versión 6,2, Media Cybernetics, Inc., Bethesda, MD: Figura 3). Correlaciones de Pearson entre la situación basal, post-isquémica y enfermedad venonos cuenta la congestión hecho con el software y los correspondientes recuentos manuales en 10 sujetos fueron 0,78, 0,78, y 0,71, respectivamente (todos p &lt;0,05), lo que indica un acuerdo razonable entre los dos métodos. La fiabilidad de los recuentos basados ​​en computadoras es ligeramente menor que el de recuentos manuales pero todavía alta (coeficiente de correlación intraclase = 0,91 para la línea de base, 0,86 por post-isquémica, y 0,84 para la oclusión venosa). Tenemos datos no publicados que demuestran también la asociación de cuentas automatizadas con múltiples factores de riesgo cardiovascular como la hipertensión, que estamos preparando para su publicación. </li><li> La Tabla 1 resume las mediciones de la densidad capilar y cálculos. Reclutamiento ciento capilar se evaluó dividiendo el aumento de la densidad capilar inducida por la hiperemia reactiva postocclusive (postocclusive reactiva densidad hiperemia capilar menos densidad basal capilar), por la densidad capilar máxima (observada durante pasivo venonos oclusión). Porcentaje de capilares perfundidos representa la proporción de todos los presentes capilares que son perfundidos (funcionalmente activo), y se calcula dividiendo la densidad capilar postocclusive reactiva hiperemia por la densidad capilar máxima. Tanto el reclutamiento ciento por ciento capilar y los capilares perfundidos reflejan el número de capilares funcionales. Los valores más bajos para estas medidas indican rarefacción capilar funcional. </li></ol> 2. Evaluación de la función endotelial <ol><li> La función endotelial se evaluó antes y después de la hiperemia reactiva postocclusive, utilizando mediciones no invasivas de pletismografía de flujo sanguíneo del antebrazo, de acuerdo con el método de Sivertsson, 4 que utiliza el estímulo dependiente del endotelio de la hiperemia reactiva para inducir la vasodilatación. </li><li> Con el sujeto en posición sentada después de 10 min de reposo en posición supina, una galga de caucho de mercurio en la cepa estirada a 10% más allá de su longitud de reposo es enrollado around del sujeto antebrazo 5 cm por debajo de la fosa antecubital. </li><li> La cepa de calibre está conectado a un pletismógrafo (CE-4: DE Hokanson, Inc; Bellevue, WA), que a su vez está conectado a un registrador de Doppler (CW-1; DE Hokanson, Inc; Belleveue, WA). </li><li> Un manguito de brazo superior oclusión se aplica, y el brazo está suspendido cómodamente al nivel del corazón usando un vendaje eslinga conectada a un polo intravenosa ajustable. Sistólica y diastólica y frecuencia cardíaca se obtienen con un Dinamap ProCare manguito 100 automático BP (GE Healthcare, Piscataway, NJ) colocado en el brazo opuesto. </li><li> Un manguito pediátrico alrededor de la muñeca se infla a 200 mm Hg para ocluir el flujo a la mano. El manguito de brazo superior es inflada a 50 mm Hg, se desinfla para 1,5 s, y luego vuelto a inflar rápidamente antes de cada medición del flujo sanguíneo del antebrazo, que se obtiene a través de la expansión de la galga de tensión coloca alrededor del antebrazo. </li><li> Flujo sanguíneo del antebrazo (FBF) se mide en la línea base descansaba (FBF base) y de nuevo unt postocclusive hiperemia inducida por la vasodilatación máxima (FBF max). Para las mediciones de referencia de flujo de sangre, cuatro curvas consecutivas FBF se obtienen dentro de 30 seg (FBF base). </li><li> La oclusión arterial se infla entonces a 40 mm Hg por encima de la presión sistólica de 10 min. Después de la liberación de la oclusión arterial (hiperemia reactiva postocclusive), cuatro curvas FBF consecutivos se obtienen dentro de los 30 primeros segundos de flujo (FBF max). </li><li> La relación FBF max / FBF base se calcula como una estimación de la vasodilatación, dividiendo la media de los cuatro valores de FBF max por la media de los cuatro valores de base FBF. 5 resistencia vascular del antebrazo a la vasodilatación máxima (FVR max) se calcula como la la presión arterial media (MAP) dividido por FBF max. FBF max durante la hiperemia reactiva está directamente relacionada con FBF máxima después de la infusión intraarterial de acetilcolina, un vasodilatador dependiente del endotelio. 6 </sup&gt; En consecuencia, max FBF y la relación de la base FBF max / FBF se aceptan medidas no invasivas de la función endotelial. 6.8 Además, tanto FBF max y FVR reflejar los cambios estructurales (resistencia de la arteria aumentado pared / luz ratio) 9. </li></ol>

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Los autores no tienen conflictos de intereses financieros relacionados con la realización o publicación de esta obra a revelar.

Capilaroscopia (microscopia capilar) es una medida no estándar de la estructura capilar. Sin embargo, en la actualidad, no existen métodos estándar para la evaluación directa de structure.Furthermore capilar, microscopía capilar ha sido ampliamente utilizado para la evaluación directa de capillarydensity en un cuerpo grande y creciente de trabajo publicado 12, 13, 10, 11, 14-18 . Adicionalmente, se han validado la técnica de microscopía capilar mediante la correlación de los resultados capilaroscopia...

non-invasive assessment of microvascular and endothelial function

Los autores han utilizado capilaroscopia antebrazo y técnicas de flujo de sangre para investigar el papel de la disfunción microvascular en la patogénesis de la enfermedad cardiovascular. Capilaroscopia es un no-invasivo, metodología relativamente barato para la visualización directa de la microcirculación. Reclutamiento ciento capilar se evaluó dividiendo el aumento de la densidad capilar inducida por postocclusive hiperemia reactiva (postocclusive reactiva densidad hiperemia capilar menos densidad basal capilar), por la máxima densidad capilar (observada durante la oclusión venosa pasiva). Porcentaje de capilares perfundidos representa la proporción de todos los presentes capilares que son perfundidos (funcionalmente activo), y se calcula dividiendo la densidad capilar postocclusive reactiva hiperemia por la densidad capilar máxima. Tanto el reclutamiento ciento por ciento capilar y los capilares perfundidos reflejan el número de capilares funcionales. El flujo sanguíneo del antebrazo (FBF) Técnica de provides aceptado medidas no invasivas de la función endotelial: La relación FBF max / FBF base se calcula como una estimación de la vasodilatación, dividiendo la media de los cuatro valores de FBF max por la media de los cuatro valores de base FBF. Resistencia vascular del antebrazo a la vasodilatación máxima (FVR max) se calcula como la presión arterial media (MAP) dividido por FBF max. Tanto el capilaroscopia y técnicas de antebrazo son fácilmente aceptable para los pacientes y se puede aprender rápidamente. La función endotelial microvascular y las medidas obtenidas con los métodos descritos en este documento pueden ser útiles en el futuro clínicos de pacientes cardiovasculares estrategias de reducción de riesgos. Como hemos publicado informes que demuestran que la disfunción endotelial microvascular y se encuentran en las etapas iniciales de la hipertensión como prehipertensión, medidas de la función endotelial y microvasculares pueden llegar a ayudar en la identificación temprana, Estratificación del riesgo vascular y la prevención de patologías en fase terminal, con sus consecuencias potencialmente fatales.

Las diferencias en la aparición de la microvasculatura entre personas normotensas e hipertensas son fácilmente evidentes mediante la comparación de las figuras 4 y 5. Figura 4 muestra la red típico de recta capilares en filas bien organizadas en un individuo normotensos. En contraste, la Figura 5 muestra un patrón más desordenado de encogido capilares, en espiral. Los autores tienen un interés continuo en el papel de la disfunción mi...

Watch this Scientific Journal Video about Non-invasive Assessment of Microvascular and Endothelial Function at JoVE.com

Non-invasive Assessment of Microvascular and Endothelial Function

Capilaroscopia es un no-invasivo, metodología relativamente barato para la visualización directa de la microcirculación. La sangre del antebrazo técnica de flujo proporciona aceptados medidas no invasivas de la función endotelial.

La evaluación no invasiva de la función endotelial microvascular y

The authors have utilized capillaroscopy and forearm blood flow techniques to investigate the role of microvascular dysfunction in pathogenesis of ...

non-invasive-assessment-of-microvascular-and-endothelial-function

Research

JoVE Journal

Medicine

16.1K vistas.  Thomas Jefferson University. Capilaroscopia es un no-invasivo, metodología relativamente barato para la visualización directa de la microcirculación. La sangre del antebrazo técnica de flujo proporciona aceptados medidas no invasivas de la función endotelial.

Video: Non-invasive Assessment of Microvascular and Endothelial Function

An in vivo Rodent Model of Contraction-induced Injury and Non-invasive Monitoring of Recovery

Muscle strains are one of the most common complaints treated by physicians. A muscle injury is typically diagnosed from the patient history and physical exam alone, however the clinical presentation can vary greatly depending on the extent of injury, the patient's pain tolerance, etc. In patients with muscle injury or muscle disease, assessment of muscle damage is typically limited to clinical signs, such as tenderness, strength, range of motion, and more recently, imaging studies. Biological markers, such as serum creatine kinase levels, are typically elevated with muscle injury, but their levels do not always correlate with the loss of force production. This is even true of histological findings from animals, which provide a "direct measure" of damage, but do not account for all the loss of function. Some have argued that the most comprehensive measure of the overall health of the muscle in contractile force. Because muscle injury is a random event that occurs under a variety of biomechanical conditions, it is difficult to study. Here, we describe an in vivo animal model to measure torque and to produce a reliable muscle injury. We also describe our model for measurement of force from an isolated muscle in situ. Furthermore, we describe our small animal MRI procedure.

An in vivo Rodent Model of Contraction-induced Injury and Non-invasive Monitoring of Recovery

An in vivo animal model of injury is described. The method takes advantage of the subcutaneous position of the fibular nerve. Velocity, timing of muscle activation, and arc of motion are all pre-determined and synchronized using commercial software. Post injury changes are monitored in vivo using MR imaging/spectroscopy.

Un In vivo Modelo de roedores de la contracción inducida por la lesión y la monitorización no invasiva de la recuperación

Muscle strains are one of the most  common complaints treated by physicians. A muscle injury is typically diagnosed from the patient history and  physical ...

Investigación

Medicina

Non-invasive Optical Measurement of Cerebral Metabolism and Hemodynamics in Infants

Perinatal brain injury remains a significant cause of infant mortality and morbidity, but there is not yet an effective bedside tool that can accurately screen for brain injury, monitor injury evolution, or assess response to therapy. The energy used by neurons is derived largely from tissue oxidative metabolism, and neural hyperactivity and cell death are reflected by corresponding changes in cerebral oxygen metabolism (CMRO2). Thus, measures of CMRO2 are reflective of neuronal viability and provide critical diagnostic information, making CMRO2 an ideal target for bedside measurement of brain health.
Brain-imaging techniques such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT) yield measures of cerebral glucose and oxygen metabolism, but these techniques require the administration of radionucleotides, so they are used in only the most acute cases.
Continuous-wave near-infrared spectroscopy (CWNIRS) provides non-invasive and non-ionizing radiation measures of hemoglobin oxygen saturation (SO2) as a surrogate for cerebral oxygen consumption. However, SO2 is less than ideal as a surrogate for cerebral oxygen metabolism as it is influenced by both oxygen delivery and consumption. Furthermore, measurements of SO2 are not sensitive enough to detect brain injury hours after the insult 1,2, because oxygen consumption and delivery reach equilibrium after acute transients 3. We investigated the possibility of using more sophisticated NIRS optical methods to quantify cerebral oxygen metabolism at the bedside in healthy and brain-injured newborns. More specifically, we combined the frequency-domain NIRS (FDNIRS) measure of SO2 with the diffuse correlation spectroscopy (DCS) measure of blood flow index (CBFi) to yield an index of CMRO2 (CMRO2i) 4,5.
With the combined FDNIRS/DCS system we are able to quantify cerebral metabolism and hemodynamics. This represents an improvement over CWNIRS for detecting brain health, brain development, and response to therapy in neonates. Moreover, this method adheres to all neonatal intensive care unit (NICU) policies on infection control and institutional policies on laser safety. Future work will seek to integrate the two instruments to reduce acquisition time at the bedside and to implement real-time feedback on data quality to reduce the rate of data rejection.

We combined frequency-domain near-infrared spectroscopy measures of cerebral hemoglobin oxygenation with diffuse correlation spectroscopy measures of cerebral blood flow index to estimate an index of oxygen metabolism. We tested the utility of this measure as a bedside screening tool to evaluate the health and development of the newborn brain.

No invasiva de medición óptica del metabolismo cerebral en lactantes y Hemodinámica

Perinatal brain injury remains a significant cause of infant mortality  and morbidity, but there is not yet an effective bedside tool that can  accurately ...

Murine Spinotrapezius Model to Assess the Impact of Arteriolar Ligation on Microvascular Function and Remodeling

The murine spinotrapezius is a thin, superficial skeletal support muscle that extends from T3 to L4, and is easily accessible via dorsal skin incision. Its unique anatomy makes the spinotrapezius useful for investigation of ischemic injury and subsequent microvascular remodeling. Here, we demonstrate an arteriolar ligation model in the murine spinotrapezius muscle that was developed by our research team and previously published1-3. For certain vulnerable mouse strains, such as the Balb/c mouse, this ligation surgery reliably creates skeletal muscle ischemia and serves as a platform for investigating therapies that stimulate revascularization. Methods of assessment are also demonstrated, including the use of intravital and confocal microscopy. The spinotrapezius is well suited to such imaging studies due to its accessibility (superficial dorsal anatomy) and relative thinness (60-200 &mu;m). The spinotrapezius muscle can be mounted en face, facilitating imaging of whole-muscle microvascular networks without histological sectioning. We describe the use of intravital microscopy to acquire metrics following a functional vasodilation procedure; specifically, the increase in arterilar diameter as a result of muscle contraction. We also demonstrate the procedures for harvesting and fixing the tissues, a necessary precursor to immunostaining studies and the use of confocal microscopy.

We demonstrate a novel arterial ligation model in murine spinotrapezius muscle, including a step-by-step procedure and description of required instrumentation. We describe the surgery and relevant outcome measurements relating to vascular network remodeling and functional vasodilation using intravital and confocal microscopy.

Modelo murino Spinotrapezius para evaluar el impacto de la ligadura arteriolar en la función microvascular y Remodelación

The murine spinotrapezius is a thin, superficial skeletal support muscle that extends from T3 to L4, and is easily accessible via dorsal skin incision. ...

A Methodological Approach to Non-invasive Assessments of Vascular Function and Morphology

The endothelium is the innermost lining of the vasculature and is involved in the maintenance of vascular homeostasis. Damage to the endothelium may predispose the vessel to atherosclerosis and increase the risk for cardiovascular disease. Assessments of peripheral endothelial function are good indicators of early abnormalities in the vascular wall and correlate well with assessments of coronary endothelial function. The present manuscript details the important methodological steps necessary for the assessment of microvascular endothelial function using laser Doppler imaging with iontophoresis, large vessel endothelial function using flow-mediated dilatation, and carotid atherosclerosis using carotid artery ultrasound. A discussion on the methodological considerations for each of the techniques is also presented, and recommendations are made for future research.

The present article describes the methodological considerations for several non-invasive assessments of vascular function and morphology that are commonly used in medical research to assess different stages of atherosclerosis.

Un enfoque metodológico para las evaluaciones no invasivas de la función vascular y Morfología

The endothelium is the innermost lining of the vasculature and is involved in the maintenance of vascular homeostasis.  Damage to the endothelium may ...

Non-invasive Assessment of the Efficacy of New Therapeutics for Intestinal Pathologies Using Serial Endoscopic Imaging of Live Mice

Animal models of inflammatory bowel disease (IBD) and colorectal cancer (CRC) have provided significant insight into the cell intrinsic and extrinsic mechanisms that contribute to the onset and progression of intestinal diseases. The identification of new molecules that promote these pathologies has led to a flurry of activity focused on the development of potential new therapies to inhibit their function. As a result, various pre-clinical mouse models with an intact immune system and stromal microenvironment are now heavily used. Here we describe three experimental protocols to test the efficacy of new therapeutics in pre-clinical models of (1) acute mucosal damage, (2) chronic colitis and/or colitis-associated colon cancer, and (3) sporadic colorectal cancer. We also outline procedures for serial endoscopic examination that can be used to document the therapeutic response of an individual tumor and to monitor the health of individual mice. These protocols provide complementary experimental platforms to test the effectiveness of therapeutic compounds shown to be well tolerated by mice.

We describe methods for longitudinal monitoring of the efficacy of therapeutics for the treatment of colonic pathologies in mice using a rigid endoscope. This protocol can be readily used for the characterization of the therapeutic response of an individual tumor in live mice and also for monitoring potential disease relapse.

Evaluación no invasiva de la eficacia de nuevas terapias para Intestinal Patologías recurriendo a imágenes de Endoscópica serie de ratones vivos

Animal models of inflammatory bowel disease (IBD) and colorectal cancer (CRC) have provided significant insight into the cell intrinsic and extrinsic ...

Ultrasound Assessment of Endothelial Function: A Technical Guideline of the Flow-mediated Dilation Test

Cardiovascular disease is the primary cause of mortality and a major cause of disability worldwide. The dysfunction of the vascular endothelium is a pathological condition characterized mainly by a disruption in the balance between vasodilator and vasoconstrictor substances and is proposed to play an important role in the development of atherosclerotic cardiovascular disease. Therefore, a precise evaluation of endothelial function in humans represents an important tool that could help better understand the etiology of multiple cardio-centric pathologies.
Over the past twenty-five years, many methodological approaches have been developed to provide an assessment of endothelial function in humans. Introduced in 1989, the FMD test incorporates a forearm occlusion and subsequent reactive hyperemia that promotes nitric oxide production and vasodilation of the brachial artery. The FMD test is now the most widely utilized, non-invasive, ultrasonic assessment of endothelial function in humans and has been associated with future cardiovascular events.
Although the FMD test could have clinical utility, it is a physiological assessment that has inherited several confounding factors that need to be considered. This article describes a standardized protocol for determining FMD including the recommended methodology to help minimize the physiological and technical issues and improve the precision and reproducibility of the assessment.

The flow mediated dilation (FMD) test is the most commonly utilized, non-invasive, ultrasound assessment of endothelial function in humans. Although the FMD test has been related with the prediction of future cardiovascular disease and events, it is a physiological assessment with many inherent confounding factors that need to be considered.

La evaluación ecográfica de la función endotelial: Una guía técnica de la prueba de dilatación mediada por flujo

Cardiovascular disease is the primary cause of mortality and a major cause of disability worldwide. The dysfunction of the vascular endothelium is a ...

Non-invasive Assessments of Subjective and Objective Recovery Characteristics Following an Exhaustive Jump Protocol

Fast recovery after strenuous exercise is important in sports and is often studied via cryotherapy applications. Cryotherapy has a significant vasoconstrictive effect, which seems to be the leading factor in its effectiveness. The resulting enhanced recovery can be measured by using both objective and subjective parameters. Two commonly measured subjective characteristics of recovery are delayed-onset muscle soreness (DOMS) and ratings of perceived exertion (RPE). Two important objective recovery characteristics are countermovement jump (CMJ) performance and peak power output (PPO). Here, we provide a detailed protocol to induce muscular exhaustion of the frontal thighs with a self-paced, 3 x 30 countermovement jump protocol (30-s rest between each set). This randomized controlled trial protocol explains how to perform local cryotherapy cuff application (+ 8 &#176;C for 20 min) and thermoneutral cuff application (+ 32 &#176;C for 20 min) on both thighs as two possible post-exercise recovery modalities. Finally, we provide a non-invasive protocol to measure the effects of these two recovery modalities on subjective (i.e., DOMS of both frontal thighs and RPE) and objective recovery (i.e., CMJ and PPO) characteristics 24, 48, and 72 h post-application. The advantage of this method is that it provides a tool for researchers or coaches to induce muscular exhaustion, without using any expensive devices; to implement local cooling strategies; and to measure both subjective and objective recovery, without using invasive methods. Limitations of this protocol are that the 30 s rest period between sets is very short, and the cardiovascular demand is very high. Future studies may find the assessment of maximum voluntary contractions to be a more sensitive assessment of muscular exhaustion compared to CMJs.

This protocol describes the procedure for non-invasive recovery assessments during a 72 h recovery period. This protocol induces muscular exhaustion of the frontal thighs using countermovement jumps and uses either local cold-cuff or thermoneutral-cuff application as a recovery modality.

Evaluaciones no invasivas de las características de recuperación subjetiva y objetiva después de un protocolo de salto exhaustivo

Fast recovery after strenuous exercise is important in sports and is often studied via cryotherapy applications. Cryotherapy has a significant ...

Assessment of Human Adipose Tissue Microvascular Function Using Videomicroscopy

While obesity is closely linked to the development of metabolic and cardiovascular disease, little is known about mechanisms that govern these processes. It is hypothesized that pro-atherogenic mediators released from fat tissues particularly in association with central/visceral adiposity may promote pathogenic vascular changes locally and systemically, and the notion that cardiovascular disease may be the consequence of adipose tissue dysfunction continues to evolve. Here, we describe a unique method of videomicroscopy that involves analysis of vasodilator and vasoconstrictor responses of intact small human arterioles removed from the adipose depot of living human subjects. Videomicroscopy is used to examine functional properties of isolated microvessels in response to pharmacological or physiological stimuli using a pressured system that mimics in vivo conditions. The technique is a useful approach to gain understanding of the pathophysiology and molecular mechanisms that contribute to vascular dysfunction locally within the adipose tissue milieu. Moreover, abnormalities in the adipose tissue microvasculature have also been linked with systemic diseases. We applied this technique to examine depot-specific vascular responses in obese subjects. We assessed endothelium-dependent vasodilation to both increased flow and acetylcholine in adipose arterioles (50 - 350 &#181;m internal diameter, 2 - 3 mm in length) isolated from two different adipose depots during bariatric surgery from the same individual. We demonstrated that arterioles from visceral fat exhibit impaired endothelium-dependent vasodilation compared to vessels isolated from the subcutaneous depot. The findings suggest that the visceral microenvironment is associated with vascular endothelial dysfunction which may be relevant to clinical observation linking increased visceral adiposity to systemic disease mechanisms. The videomicroscopy technique can be used to examine vascular phenotypes from different fat depots as well as compare findings across individuals with different degrees of obesity and metabolic dysfunction. The method can also be used to examine vascular responses longitudinally in response to clinical interventions.

Videomicroscopy systems are used to examine functional properties of isolated adipose tissue arterioles in response to physiological and pharmacological stimuli. This technique can be used to examine microvascular phenotypes in different adipose tissue domains in obese humans.

Evaluación de la función Microvascular del tejido adiposo humano mediante videomicroscopía

While obesity is closely linked to the development of metabolic and cardiovascular disease, little is known about mechanisms that govern these processes. ...

Non-invasive Assessment of Dorsiflexor Muscle Function in Mice

Assessment of skeletal muscle contractile function is an important measurement for both clinical and research purposes. Numerous conditions can negatively affect skeletal muscle. This can result in a loss of muscle mass (atrophy) and/or loss of muscle quality (reduced force per unit of muscle mass), both of which are prevalent in chronic disease, muscle-specific disease, immobilization, and aging (sarcopenia). Skeletal muscle function in animals can be evaluated by a range of different tests. All tests have limitations related to the physiological testing environment, and the selection of a specific test often depends on the nature of the experiments. Here, we describe an in vivo, non-invasive technique involving a helpful and easy assessment of force frequency-curve (FFC) in mice that can be performed on the same animal over time. This permits monitoring of disease progression and/or efficacy&#160;of a potential therapeutic treatment.

Measurement of rodent skeletal muscle contractile function is a useful tool that can be used to track disease progression as well as efficacy of therapeutic intervention. We describe here the non-invasive, in vivo assessment of the dorsiflexor muscles that can be repeated over time in the same mouse.

Evaluación no invasiva de la función muscular de los dorsiflexores en ratones

Assessment of skeletal muscle contractile function is an important measurement for both clinical and research purposes. Numerous conditions can negatively ...

A Computerized Functional Skills Assessment and Training Program Targeting Technology Based Everyday Functional Skills

Today, many functional skills are technology-based, so development of a technology-based training program has broad importance. Here we present a computerized functional skills training program that was paired in half of the participants with a commercially available cognitive training (CCT) program.
Non-impaired older individuals (NC) aged 60+ (n=45) and similarly aged individuals with mild cognitive impairment (MCI; n=50) were randomized to receive 12 weeks of twice-weekly computerized functional skills training (CFST) or 12 weeks of twice-weekly sessions split between CCT and CFST. Skills trained were use of an ATM; internet banking; ticket kiosk; telephone and internet prescription refill; medication management; and internet shopping. As with previous functional capacity assessments, we focus on completion time for each simulation.
51 participants completed the training program, either by mastering all 6 tasks (34) or completing 12 weeks of training. 44 more participants completed 4 or more training sessions so they were also analyzed for improvement up to their last training session. Completion time for all 6 tests significantly improved from the baseline assessment to the final training session in both groups of participants (all p&#60;0.001 with an average improvement in task completion time of 45%). Further, there was no differential improvement in MCI and NC in the 6 tests from baseline to end of training (all t&#60;1.66, all p&#62;0.12). Finally, combined CCT plus CFST did not differ from CSFT alone on any of the percent-change score measures (all t&#60;1.64, all p&#62;0.11).
Both NC and MCI groups evidenced substantial improvements in performance. CCT supplementation led to similar functional gains with half as many training sessions. The NC participants proceeded through the training fairly rapidly even without CCT supplementation; MCI participants required more training but learned equivalently. These findings suggest that even in cases with memory impairments, functional skills can be efficiently learned with training.

This training protocol uses computerized training to teach technology-related everyday functional skills. These skills include financial skills, travel and transit, as well as medication management.

Un Programa Computarizado de Evaluación y Capacitación de Habilidades Funcionales Dirigido a Las Habilidades Funcionales Diarias Basadas en La Tecnología