This work is funded by the Swiss National Foundation (31_138429) and Synapsis Foundation for the support of research on Alzheimer&#8217;s disease.

Todos los procedimientos con animales están en conformidad con la Directiva de la UE 2010/63 / UE relativa a la protección de los animales utilizados para fines científicos y son aprobados por el Comité local de Cuidado de Animales (Cantón de Friburgo, Suiza). 1. Preparación Animal <ol><li> Los animales experimentales <ol><li> Realizar experimentos sobre tipo salvaje adulto de sexo masculino y de ratones transgénicos (C57BL / 6 de fondo) de 3-5 meses de edad. Los tres grupos de ratones corresponden a los controles de tipo salvaje (littermate grupo A, Jagged1 flox / flox 19) y dos líneas condicionales de ratón KO (grupo B, C y Jagged1ncKO, Jagged1gcKO). </li><li> Los ratones en condiciones de laboratorio estándar en una habitación ventilada, con un ciclo de oscuridad / luz controlada 12 horas y proporcionan alimento y agua ad libitum. </li></ol></li></ol> 2. Configuración Experimental <ol><li> Arena Experimental <ol><li> Para el ámbito experimental, utilizar una jaula ratón esterilizada limpia (36 cm largo x 20.5 cm de ancho x 13.5 cm de altura) (Figura 1). </li><li> Asigne a cada ratón a una jaula numerada con ropa de cama fresca, 3 cm de alto. Si se vuelven a utilizar jaulas, como en la prueba de sensibilidad al olor, tome las siguientes medidas para evitar la contaminación cruzada entre los olores y ratones. <ol><li> Marque el lado del agua. </li><li> Limpiar las paredes estrechas de las jaulas con dos papeles de seda rociadas con 70% de etanol, uno para cada lado. </li><li> Apilar las jaulas de acuerdo con el genotipo de los ratones y almacenar temporalmente bajo una campana laminar. </li></ol></li></ol></li><li> Cámara <ol><li> Montar una cámara en un trípode personalizada con el objetivo a 58 cm de la parte inferior de la jaula (Figura 1A). Fijar la posición del trípode y la jaula y delimitar con marcas para permitir que la cámara se centra en la parte superior de la jaula. </li><li> Grabar videos en 320 píxeles x 240 píxeles, 15,08 fotogramas por segundo como archivos MOV. </li></ol></li><li> Olores <ol><li> Resuspender el scents, cuando se indique, en el disolvente en el que son solubles. </li><li> Para la prueba de preferencia de uso de mantequilla de maní. Resuspender la mantequilla de cacahuete en aceite de cacahuete (10% w / v). </li><li> Para la utilización prueba de evitación puro 2-metilbutírico (2-MB) ácido (98%). </li><li> Para la prueba de sensibilidad, utilizar orina femenina de la misma colonia ratón y de fondo (C57BL / 6). <ol><li> Por conveniencia recoger la orina 1-2 días antes de la prueba olfativa. Restringir y mantenga pulsado el ratón debajo de la capilla con su vientre encima de la rejilla de la jaula. Bajo la rejilla jaula colocar una placa de Petri de plástico para recoger las gotas de orina. </li><li> Recoger la orina de cada mujer en un tubo de 1,5 ml y mezclar todas las muestras de orina para normalizar la variabilidad entre animales. Almacenar a -20 ° C hasta su uso. </li><li> En el día del experimento, descongelar la orina y realizar 4 diluciones en agua doblemente destilada a un factor de dilución de 10 (1:10, 1: 100, 1: 1.000; 1: 10.000). </li></ol></li></ol></li></ol>3. Las pruebas olfativas Nota: En este protocolo olores han sido elegidos deliberadamente que se perciben como atrayentes fuertes (mantequilla de maní y orina femenina) o repelente fuerte (ácido 2-MB) 15. Es importante para llevar a cabo la preferencia y las pruebas de sensibilidad a los olores agradables antes de la prueba de evitación para eliminar la posibilidad de cualquier interferencia con el comportamiento olfativo. Sin embargo, en aras de la simplicidad, en este trabajo, prueba de preferencia y la evitación será tanto se describe en la prueba de percepción. Cada sesión de comportamiento comienza con una fase de habituación. <ol><li> La habituación fase <ol><li> Colocar el animal en la jaula asignado limpia y se deja explorar durante 5 min (Figura 1B). Desde el entorno de la jaula experimental es familiar a la jaula de alojamiento, este corto período de tiempo es suficiente para permitir la habituación. </li><li> Si se completa la prueba de sensibilidad en un solo día, realice habituación sólo una vez antes de la application de la más alta olor diluido. Si la prueba de sensibilidad se lleva a cabo en diferentes días, en cada día se necesita una fase de habituación en una nueva jaula limpia. </li></ol></li><li> Prueba de Percepción <ol><li> Después de la habituación, activar la cámara e inmediatamente pipetear 60 l de la agradable aroma (mantequilla de maní) y 60 l de la olor neutro (agua del grifo) sobre las paredes opuestas de la jaula en alrededor de 10 cm desde la parte inferior (Figura 1C). </li><li> Deje que el ratón explorar los olores durante 2 min (Figura 1D). A partir de entonces, apague la cámara. </li><li> En este punto, continúe con la próxima ratón a partir de la fase de habituación. Realizar la prueba de evitación exactamente de la misma manera mediante la aplicación de 60 l de la olor repelente (ácido 2-MB) y 60 l de agua. </li></ol></li><li> Prueba de sensibilidad <ol><li> Evaluar el umbral de atracción de ratones macho a concentraciones crecientes de orina femenina en el siguiente orden: 1: 10.000; 1: 1.000; 1: 100; 1:10 y en la orina pura. </li><li> Después de la habituación, exponer cada ratón para la mayor dilución pipeta por el experimentador como se describe anteriormente en 3.2.1. </li><li> Registre el comportamiento exploratorio de la orina frente de agua, dentro de un plazo de 2 minutos en una cámara de vídeo. Después de todas las cohortes ratones son la prueba de la mayor dilución (1: 10.000), exponerlo a una mayor concentración de la orina, como se indicó anteriormente. </li></ol></li></ol> 4. Post-hoc de análisis de datos Nota: Todas las pruebas de comportamiento descritos se procesan post hoc siguiendo las instrucciones de análisis de datos. <ol><li> Abrir archivos MOV en ImageJ para sistemas Windows <ol><li> Instalar Quick Time para Java usando la configuración personalizada de http://www.apple.com/quicktime/download. </li><li> Instale el plugin de Quick Time desde el sitio web ImageJ (http://rsb.info.nih.gov/ij/plugins/qt-capture.html). </li><li> Importe el QTJava.zip (C: Archivos de programa QuickTime QTSystem) en las extens bibliotecaión de ImageJ (.ImageJ jre lib ext). </li><li> Copiar también el QTJava.zip en la carpeta plugins y cambiarle el nombre como QTJava.jar. </li><li> Instale los seis guiones adjuntos en la carpeta Macros (ImageJ plugins Macros). </li><li> Abrir ImageJ y compilar y ejecutar el plugin de Quick Time, a partir de entonces cerca ImageJ. </li><li> Reabrir ImageJ y abra el archivo MOV utilizando Archivo&gt; Importar&gt; usando Quick Time. </li></ol></li><li> Ajuste de vídeo <ol><li> Una vez que el archivo de vídeo se abre en ImageJ, cortar el vídeo con el fin de obtener una constante exploración 2 min desde el momento en que el experimentador ha pipetearon los odorantes en la jaula (T0). Identificar la estructura correspondiente al T0 y quitar los marcos anteriores utilizando incrementos de 1 (ImageJ imagen Pilas ToolsSlice removedor). Utilice el mismo comando para eliminar todas las tramas que superan la exploración 2 min. </li><li> Asegúrese de que la jaula está centrado y si es necesario, utilice la Imagen&gt; Transformar&gt; comando Rotar para alinearlo. </li></ol></li><li> Véaseo Procesamiento Nota: El procesamiento de vídeo es totalmente asistida por ordenador y usa comandos macros que acompañan este documento. <ol><li> Con el fin de restringir el área en la jaula de un 127 píxeles x 218 píxeles Tamaño de ejecutar el Paso 1 macro desde el Plugin&gt; Macros&gt; Ejecutar comando. Mueva el rectángulo fijo sobre la jaula (Figura 2, Paso 1). </li><li> Recortar el área de la jaula en la región de interés (ROI) con el Paso 2 macro (Figura 2, Paso 2). </li><li> Utilice la macro Paso 3 para extraer la imagen del ratón del fondo mediante la asignación de una señal de umbral, eliminación de puntos y el filtrado de la varianza de la señal. Los valores de salida en la trama eje Z indican los valores de gris medio, correspondiente a la intensidad de la sombra del ratón en movimiento dentro de la ROI de la &quot;cámara de agua&quot; durante la exploración 2 min. Copie los resultados en una hoja de cálculo denominada según el retorno de la inversión en un archivo de hoja de cálculo (Figura 2, Paso 3). </li><li> Utilice el Paso 4 macro paraextraer los valores medios de grises el ratón en la ROI &quot;cámara de olor&quot;. Copie los resultados en una hoja de cálculo denominada según el retorno de la inversión en la misma hoja de cálculo como en 4.3.3 (Figura 2, Paso 4). </li><li> Con el fin de restringir aún más el análisis del movimiento del ratón en el retorno de la inversión &quot;perímetro agua&quot; utilizar el Paso 5 macro. Copie el resultado en la hoja de cálculo llamado según el retorno de la inversión en la misma hoja de cálculo como en 4.3.3 (Figura 2, Paso 5). </li><li> Para restringir el análisis del movimiento del ratón en el retorno de la inversión &quot;olor perímetro&quot; utilizar el Paso 6 macro. Copie el resultado en la hoja de cálculo llamado de acuerdo con el archivo de hoja de cálculo de retorno de la inversión como en 4.3.3 (Figura 2, Paso 6). </li><li> Procesar todos los vídeos y comprobar la consistencia en el número de fotogramas por animales. Aquí, registrar todos los animales de 1810 tramas correspondientes a una sesión de exploración de 2 min. </li><li> Para cada animal y para cada tipo de ROI con marcos va de gris mediolues mayor que 0. Divide el número de fotogramas por los valores correspondientes a 1 segundo y obtener los segundos transcurridos en cada retorno de la inversión. </li></ol></li></ol> 5. Análisis estadístico <ol><li> Para cada prueba verificar la homogeneidad de la varianza dentro de grupos / genotipos mediante la prueba de Bartlett utilizando la fórmula disponible en http://www.real-statistics.com/one-way-analysis-of-variance-anova/homogeneity-variances/. </li><li> En la prueba de la atracción y evitación, realizar comparaciones entre los tiempos pasados ​​con agua frente olor dentro de un grupo utilizando la prueba t de Student no direccional asumiendo varianzas iguales o desiguales en función de los resultados de la prueba de Bartlett. Compare los tiempos pasados ​​con los olores restados por el tiempo que pasa con el agua entre los genotipos mediante un modelo lineal con la prueba post-hoc de Bonferroni. </li><li> En la prueba de sensibilidad a analizar las comparaciones del tiempo pasado con el olor restado del tiempo pasado con finalesr entre los grupos en un diluciones específicas de la orina por un modelo lineal con la prueba post-hoc de Bonferroni. Comparar la sensibilidad entre los grupos a las concentraciones crecientes de olor en un 2-Way ANOVA con repeticiones con test post-hoc de Bonferroni. </li><li> La interacción entre genotipos y tratamientos en la prueba de la atracción y la evasión son investigados por 2 vías ANOVA con test post-hoc de Bonferroni. </li></ol>

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There is no conflict of interest.

Las pruebas que se proponen en este protocolo permiten evaluar diferentes aspectos del comportamiento olfativo innata en ratones: la percepción de los olores, la discriminación entre los olores frente a agua y la sensibilidad a los olores. Este protocolo se puede aplicar a cualquier olor de acuerdo con la preferencia y la escala de evitación previamente demostrado 15. Dado que el protocolo se basa en la actividad exploratoria es importante que los ratones no muestran ningún deterioro motor o la ansiedad q...

El olfato es una de las funciones sensoriales más desarrollados e importantes en los mamíferos. Cualquier alteración en la actividad olfativa puede afectar la ingesta de alimentos, el comportamiento social y, en el peor de los casos, incluso la supervivencia. En los seres humanos, el deterioro del olfato es dependiente de 1 año y es considerado un fuerte predictor de trastornos neurológicos 2-6. La prueba de identificación del olfato desarrollado por la Universidad de Pennsylvania representa actualmente una de las pruebas más utilizadas, no invasivos y cuantificables, de diagnóstico que pueden evaluar los déficits neurológicos primeros 7 y predecir con alta probabilidad la progresión de la demencia 8,9. La accesibilidad del sistema olfativo y la prominencia del olfato en los roedores, ha desatado una intensa línea de investigación frente a los mecanismos de las funciones olfativas subyacentes 10. Hemos demostrado anteriormente que la pérdida de la función del recept señalizacióno Notch1 afecta evitar olfativa 11. En este protocolo que utilizamos ratones que carecen del ligando de señalización, Jagged1, en neuronas o células gliales para estudiar el rendimiento olfativo. Olfato innato se define por tres parámetros como la percepción, la discriminación entre los olores y la sensibilidad olfativa 4. Pruebas olfativas en roedores se puede hacer en una variedad de maneras y algunos estudios de comportamiento hacer uso de olfatómetros, que proporcionan el olor al animal en un concentraciones de vapor específicas y en un marco de tiempo precisa 12 - 14. Sin embargo, esta instrumentación es caro y puede estar disponible sólo en instalaciones especializadas. En nuestro trabajo, ofrecemos un protocolo de prueba olfativa simple, rápida y reproducible, que se lleva a cabo utilizando aromas volátiles. Las pruebas descritas percepción medida para un atrayente o un olor repelente y evaluar la discriminación entre el olor y 11,15,16 agua. Usando la misma configuración, wE también puede medir la sensibilidad a un olor a diferentes concentraciones 16,17. El procesamiento post-hoc asistida por ordenador de vídeo, inspirado en la obra de la página y sus colegas 18, ofrece resultados sin la necesidad de cegamiento experimental y permitiendo una sola persona para llevar a cabo todo el experimento. Este protocolo está destinado a proporcionar un punto de partida para estudiar el comportamiento olfativo en ratones.

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	<colgroup>
		<col span="4" />
	</colgroup>
	<tbody>
		<tr>
			<td class="xl63">Mouse cage</td>
			<td class="xl64">Italplast (Italy)</td>
			<td class="xl64">1144B</td>
			<td class="xl64">36 cm length x 20.5 cm width x 13.5 cm height</td>
		</tr>
		<tr>
			<td class="xl63">Chipped wood bedding</td>
			<td class="xl64">Abedd (Austria)</td>
			<td class="xl64">LTE E-001</td>
			<td class="xl64">3 cm high</td>
		</tr>
		<tr>
			<td class="xl63">Peanut butter</td>
			<td class="xl64">Migros (Swizterland)</td>
			<td class="xl64">NA</td>
			<td align="right" class="xl65">1:10</td>
		</tr>
		<tr>
			<td class="xl63">2-Methylbutyric</td>
			<td class="xl64">Sigma Aldrich (Switzerland)</td>
			<td class="xl64">W269514</td>
			<td class="xl64">Pure</td>
		</tr>
		<tr>
			<td class="xl63">Female Urine from fertile females of same mouse strain</td>
			<td class="xl64">NA</td>
			<td class="xl64">NA</td>
			<td class="xl64">Dilution series</td>
		</tr>
		<tr>
			<td class="xl63">Camera</td>
			<td class="xl64">Olympus (US)</td>
			<td class="xl64">Camedia C-8080</td>
			<td class="xl64">MOV files</td>
		</tr>
		<tr>
			<td class="xl63">Quicktime for Java (Windows)</td>
			<td class="xl64">Apple (USA)</td>
			<td class="xl64">NA</td>
			<td class="xl64">video plugin for visualizing MOV files</td>
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			<td class="xl63">Image J for Windows</td>
			<td class="xl64">NIH (USA)</td>
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simple and computer-assisted olfactory testing for mice

El olfato está altamente conservada entre las especies y se requiere para la reproducción y la supervivencia. En los seres humanos, el olfato es también uno de los sentidos que se ve afectado con el envejecimiento y es un fuerte predictor de enfermedades neurodegenerativas. Por lo tanto, las pruebas de olfato se utiliza como un método de diagnóstico no invasivo para detectar déficits neurológicos desde el principio. Con el fin de comprender los mecanismos subyacentes de sensibilidad olfativa red, la investigación olfativa en roedores ha cobrado impulso en la última década. A continuación, presentamos un método muy simple, eficiente en tiempo y reproducible prueba olfativa de innata percepción del olor y la sensibilidad en los ratones sin la necesidad de cualquier restricción de alimentos o agua antes. Las pruebas se realizan en un ambiente familiar a los ratones, requieren sólo los olores y una sesión de 2 minutos de exposición odorante. Se lleva a cabo el análisis, post-hoc, utilizando comandos asistida por ordenador en ImageJ y puede ser, por lo tanto,, Llevado a cabo de principio a fin por un investigador. Este protocolo no requiere ningún hardware o configuración especial y está indicado para cualquier laboratorio interesado en probar la percepción olfativa y sensibilidad.

La prueba mide la percepción de la atracción a la mantequilla de maní y la evitación de ácido 2-MB. Tres grupos de ratones se prueban y el tiempo pasado en el &quot;olor perímetro&quot; se cuantifican en comparación con agua. En la prueba de preferencia, el grupo de control A muestra preferencia significativa al olor en comparación con agua (8 t = 2,52, p &lt;0,05). Por otra parte, el grupo B no muestra ningún interés significativo para la mantequilla de maní y pasa más tiempo con agua (t 6</...

Watch this Scientific Journal Video about Simple and Computer-assisted Olfactory Testing for Mice at JoVE.com

Simple and Computer-assisted Olfactory Testing for Mice

We present a simple and unbiased olfactory test in mice. With this protocol olfactory discrimination, preference, avoidance and sensitivity to a novel odor as compared to water can be assessed in single behavioral sessions. This method is indicated for a single experimenter and analysis is based on computer-assisted video processing.

Simple y asistida por ordenador de pruebas olfativas para Ratones

Olfaction is highly conserved among species and is required for reproduction and survival.
In humans, olfaction is also one of the senses that is affected ...

simple-and-computer-assisted-olfactory-testing-for-mice

Research

JoVE Journal

Behavior

9.9K vistas.  University of Fribourg. We present a simple and unbiased olfactory test in mice. With this protocol olfactory discrimination, preference, avoidance and sensitivity to a novel odor as compared to water can be assessed in single behavioral sessions. This method is indicated for a single experimenter and analysis is based on computer-assisted video processing. 

Video: Simple and Computer-assisted Olfactory Testing for Mice

Barnes Maze Testing Strategies with Small and Large Rodent Models

Spatial learning and memory of laboratory rodents is often assessed via navigational ability in mazes, most popular of which are the water and dry-land (Barnes) mazes. Improved performance over sessions or trials is thought to reflect learning and memory of the escape cage/platform location. Considered less stressful than water mazes, the Barnes maze is a relatively simple design of a circular platform top with several holes equally spaced around the perimeter edge. All but one of the holes are false-bottomed or blind-ending, while one leads to an escape cage. Mildly aversive stimuli (e.g.&#160;bright overhead lights) provide motivation to locate the escape cage. Latency to locate the escape cage can be measured during the session; however, additional endpoints typically require video recording. From those video recordings, use of automated tracking software can generate a variety of endpoints that are similar to those produced in water mazes (e.g.&#160;distance traveled, velocity/speed, time spent in the correct quadrant, time spent moving/resting, and confirmation of latency). Type of search strategy (i.e.&#160;random, serial, or direct) can be categorized as well. Barnes maze construction and testing methodologies can differ for small rodents, such as mice, and large rodents, such as rats. For example, while extra-maze cues are effective for rats, smaller wild rodents may require intra-maze cues with a visual barrier around the maze. Appropriate stimuli must be identified which motivate the rodent to locate the escape cage. Both Barnes and water mazes can be time consuming as 4-7 test trials are typically required to detect improved learning and memory performance (e.g.&#160;shorter latencies or path lengths to locate the escape platform or cage) and/or differences between experimental groups. Even so, the Barnes maze is a widely employed behavioral assessment measuring spatial navigational abilities and their potential disruption by genetic, neurobehavioral manipulations, or drug/ toxicant exposure.

The dry-land Barnes maze is widely used to measure spatial navigation ability in response to mildly aversive stimuli. Over consecutive days, performance (e.g.&#160;latency to locate escape cage) of control subjects improves, indicative of normal learning and memory. Differences between rats and mice necessitate apparatus and methodology changes that are detailed here.

Barnes Maze estrategias de ensayo con pequeñas y grandes modelos de roedores

Spatial learning and memory of laboratory rodents is often assessed via navigational ability in mazes, most popular of which are the water and dry-land ...

Investigación

Comportamiento

Testing for Odor Discrimination and Habituation in Mice

This video demonstrates a technique to establish the presence of a normally functioning olfactory system in a mouse. The test helps determine whether the mouse can discriminate between non-social odors and social odors, whether the mouse habituates to a repeatedly presented odor, and whether the mouse demonstrates dishabituation when presented with a novel odor. Since many social behavior tests measure the experimental animal&#8217;s response to a familiar or novel mouse, false positives can be avoided by establishing that the animals can detect and discriminate between social odors. There are similar considerations in learning tests such as fear conditioning that use odor to create a novel environment or olfactory cues as an associative stimulus. Deficits in the olfactory system would impair the ability to distinguish between contexts and to form an association with an olfactory cue during fear conditioning. 
In the odor habitation/dishabituation test, the mouse is repeatedly presented with several odors. Each odor is presented three times for two minutes. The investigator records the sniffing time directed towards the odor as the measurement of olfactory responsiveness. A typical mouse shows a decrease in response to the odor over repeated presentations (habituation). The experimenter then presents a novel odor that elicits increased sniffing towards the new odor (dishabituation). After repeated presentation of the novel odor the animal again shows habituation. This protocol involves the presentation of water, two or more non-social odors, and two social odors. In addition to reducing experimental confounds, this test can provide information on the function of the olfactory systems of new knockout, knock-in, and conditional knockout mouse lines.

This manuscript describes a protocol to examine the olfactory system of rodents. The olfactory habituation/dishabituation test will allow investigators to determine whether a mouse habituates to a repeatedly presented odor and whether the mouse demonstrates dishabituation when presented a novel odor.

Las pruebas para detectar olor Discriminación y habituación en ratones

This video demonstrates a technique to establish the presence of a normally functioning olfactory system in a mouse. The test helps determine whether the ...

Morris Water Maze Test: Optimization for Mouse Strain and Testing Environment

The Morris water maze (MWM) is a commonly used task to assess hippocampal-dependent spatial learning and memory in transgenic mouse models of disease, including neurocognitive disorders such as Alzheimer&#8217;s disease. However, the background strain of the mouse model used can have a substantial effect on the observed behavioral phenotype, with some strains exhibiting superior learning ability relative to others. To ensure differences between transgene negative and transgene positive mice can be detected, identification of a training procedure sensitive to the background strain is essential. Failure to tailor the MWM protocol to the background strain of the mouse model may lead to under- or over- training, thereby masking group differences in probe trials. Here, a MWM protocol tailored for use with the F1 FVB/N x 129S6 background is described. This is a frequently used background strain to study the age-dependent effects of mutant P301L tau (rTg(TauP301L)4510 mice) on the memory deficits associated with Alzheimer&#8217;s disease. Also described is a strategy to re-optimize, as dictated by the particular testing environment utilized.

This manuscript describes a Morris water maze (MWM) protocol tailored for use with a commonly used mouse model of Alzheimer's disease. The MWM is widely used in transgenic mouse models. Implementation of a procedure sensitive to the background strain of the mouse model is essential for detecting group differences.

Morris Water Maze Prueba: Optimización de ratón Colar y entorno de pruebas

 The Morris water maze (MWM) is a commonly used task to assess hippocampal-dependent spatial learning and memory in transgenic mouse models of disease, ...

The Treadmill Fatigue Test: A Simple, High-throughput Assay of Fatigue-like Behavior for the Mouse

Fatigue is a prominent symptom in many diseases and disorders and reduces quality of life for many people. The lack of clear pathogenesis and failure of current interventions to adequately treat fatigue in all patients leaves a need for new treatment options. Despite the therapeutic need and importance of preclinical research in helping identify promising novel treatments, few preclinical assays of fatigue are available. Moreover, the most common preclinical assay used to assess fatigue-like behavior, voluntary wheel running, is not suitable for use with some strains of mice, may not be sensitive to drugs that reduce fatigue, and has relatively low throughput. The current protocol describes a novel, non-voluntary preclinical assay of fatigue-like behavior, the treadmill fatigue test, and provides evidence of its efficacy in detecting fatigue-like behavior in mice treated with a chemotherapy drug known to cause fatigue in humans and fatigue-like behavior in animals. This assay may be a beneficial alternative to wheel running, as fatigue-like behavior and potential interventions can be assessed in a greater number of mice over a shorter time frame, thus permitting faster discovery of new therapeutic options.

Fatigue is a common, undertreated and frequently poorly-understood symptom in many diseases and disorders. New preclinical assays of fatigue may help to improve current understanding and future treatment of fatigue. To that end, the current protocol provides a novel means of measuring fatigue-like behavior in the mouse.

El Ensayo de fatiga rueda de ardilla: Un ensayo sencillo, de gran procesamiento de comportamiento a fatiga similar para el ratón

Fatigue is a prominent symptom in many diseases and disorders and reduces quality of life for many people. The lack of clear pathogenesis and failure of ...

Task Interruption and Resumption Paradigm for Testing the Activation and Pursuit of an Abstract Thinking Goal

This protocol is based on the task interruption and resumption paradigm, the premise of which is that active goals lead to persistent behavior and thus a higher resumption rate after a period of delay or interruption. The task interruption and resumption protocol described in this research is tailored to test the activation of cognitive goals (e.g., a goal to think more abstractly). Cognitive goals may be pursued even during the interruption period; thus, to prevent this, the protocol involves cognitive distraction. The protocol consists of several stages. Specifically, the initial stage includes the goal activation process, where the treatment (versus control) condition receives a manipulation to activate the cognitive goal being tested by the researcher. In the next stage, participants are presented with the introduction of a task that is perceived to either satisfy or not satisfy the cognitive goal of interest. Importantly, this task is interrupted a few seconds after it begins. The task interruption forces a delay period and introduces a cognitive distraction to prevent the automatic pursuit and fulfillment of the cognitive goal. After the interruption period, participants are given a choice between resuming the interrupted task and abandoning the interrupted task to complete an alternative task instead. Among participants whose cognitive goals had been activated at the earlier stage, the task resumption rate should be higher if the task was perceived as an opportunity to satisfy (versus not satisfy) the goal. Such a finding would provide empirical evidence that the cognitive goal has been activated and pursued. In previous research, this protocol has been used to test whether causal uncertainty activates an abstract thinking goal. Adapting the protocol to test the activation of other cognitive goals is also discussed.

This protocol was designed to test the activation and pursuit of cognitive goals (e.g., an abstract thinking goal) using the task interruption and resumption paradigm. The protocol is suitable for cognitive goals that are automatically pursued once activated, as the distraction procedure prevents goal pursuit during the interruption period.

Tarea de Interrupción y reanudación de paradigma para probar la activación y la persecución de un objetivo abstracto Pensamiento

This protocol is based on the task interruption and resumption paradigm, the premise of which is that active goals lead to persistent behavior and thus a ...

A Simple and Low-cost Assay for Measuring Ambulation in Mouse Models of Muscular Dystrophy

Measuring functional outcomes in the treatment of muscular dystrophy is an essential aspect of preclinical testing. The assessment of voluntary ambulation in mouse models is a non-invasive and reproducible activity assay that is directly analogous to measures of patient ambulation such as the 6-minute walk test and related mobility scores. Many common methods for testing mouse ambulation speed and distance are based on the open field test, where an animal&#39;s free movement within an arena is measured over time. One major downside to this approach is that commercial software and equipment for high-resolution motion tracking is expensive and may require transferring mice to specialized facilities for testing. Here, we describe a low-cost, video-based system for measuring mouse ambulation that utilizes free and open-source software. Using this protocol, we demonstrate that voluntary ambulation in the dystrophin-null mdx mouse model for Duchenne muscular dystrophy (DMD) is decreased relative to wild-type mouse activity. In mdx mice expressing the utrophin transgene, these activity deficits are not observed and the total distance traveled is indistinguishable from wild-type mice. This method is effective for measuring changes in voluntary ambulation associated with dystrophic pathology, and provides a versatile platform that can be readily adapted to diverse research settings.

This protocol describes a flexible, low-cost system for measuring mouse ambulation in an open field activity assay. We show that a 6-minute ambulation assay based on this system detects a decrease in voluntary movement in mdx mice, and accurately distinguishes improvement in a muscle-specific rescue of these animals.

Un análisis Simple y de bajo costo para la medición de actividad en modelos de ratón de la Distrofia Muscular

Measuring functional outcomes in the treatment of muscular dystrophy is an essential aspect of preclinical testing. The assessment of voluntary ambulation ...

A Simple Non-invasive Method for Temporary Knockdown of Upper Limb Proprioception

Proprioception may be the least well measured of all contributors to the neural control of movement. New precise, reliable measures of proprioception are needed for clinical diagnosis of impairment, and to measure outcomes of proprioceptive training. The purpose of this simple, non-invasive method is to temporarily knockdown upper limb proprioception in healthy adults, to an extent that would be useful in the development and testing of upper limb proprioception measures. Knockdown models have two main advantages over studying humans with impaired proprioception: participant availability and the ability to control the extent of impairment across participants. Current published methods of temporary proprioception knockdown of the upper limb, such as ischemic nerve blocks and cryotherapy, are invasive, impractical, or uncomfortable for the participant. Here, vibration over the ulnar groove was used to reduce upper limb proprioception. High frequency vibration may reduce proprioceptive acuity by inhibiting pacinian corpuscle-induced input. The effect of vibration used in this protocol was confirmed using two quantitative measures. This method was simple to administer, comfortable for participants, and practical.

The goal of this protocol is to demonstrate a practical method to temporarily interfere with proprioception in the upper limb of healthy humans.

Un Simple método no invasivo para la caída temporal de propiocepción de extremidades superiores

Proprioception may be the least well measured of all contributors to the neural control of movement. New precise, reliable measures of proprioception are ...

Measuring Active and Passive Tameness Separately in Mice

Domesticated animals such as dogs and laboratory mice show a high level of tameness, which is important for humans to handle them easily. Tameness has two behavioral components: a reluctance to avoid humans (passive tameness) and a motivation to approach humans (active tameness). To quantify these components in mice, we previously developed behavioral tests for active tameness, passive tameness, and the willingness to stay on a human hand, each designed to be completed within 3 min. The data obtained were used for selective breeding, with a large number of mice analyzed per generation. The active tameness test measures the movement of the mouse toward a human hand and the contact it engages in. The passive tameness test measures the duration of time that a mouse tolerates human touch. In the stay-on-hand test, a mouse is placed on a human hand and touched slowly using the thumb of that hand; the duration of time that the animal remains on the hand is measured. Here, we describe the test set-up and apparatus, explain the procedures, and discuss the appropriate data analysis. Finally, we explain how to interpret the results.

Tameness in animals includes a reduction of avoidance responses to humans (passive tameness) and an increase in active approaches to humans (active tameness). Here, we describe detailed protocols for three behavioral tests (active tameness, passive tameness, and stay-on-hand tests) to separately measure the active and passive tameness of mice.

Medición activa y pasiva mansedumbre por separado en ratones

Domesticated animals such as dogs and laboratory mice show a high level of tameness, which is important for humans to handle them easily. Tameness has two ...

Computerized Adaptive Testing System of Functional Assessment of Stroke

The computerized adaptive testing system of the functional assessment of stroke (CAT-FAS) can simultaneously assess four functions (motor functions of the upper and lower extremities, postural control, and basic activities of daily living) with sufficient reliability and administrative efficiency. CAT, a modern measurement method, aims to provide a reliable estimate of the examinee's level of function rapidly. CAT administers only a few items whose item difficulties match an examinee's level of function and, thus, the administered items of CAT can provide sufficient information to reliably estimate the examinee's level of function in a short time. The CAT-FAS was developed through four steps: (1) determining the item bank, (2) determining the stopping rules, (3) validating the CAT-FAS, and (4) establishing a platform of online administration. The results of this study indicate that the CAT-FAS has sufficient administrative efficiency (average number of items = 8.5) and reliability (group-level Rasch reliability: 0.88 - 0.93; individual-level Rasch reliability: &#8805;70% of patients had Rasch reliability score &#8805;0.90) to simultaneously assess four functions in patients with stroke. In addition, because the CAT-FAS is a computer-based test, the CAT-FAS has three additional advantages: the automatic calculation of scores, the immediate storage of data, and the easy exporting of data. These advantages of the CAT-FAS will be beneficial to data management for clinicians and researchers.

Here, we present a protocol to develop the computerized adaptive testing system of the functional assessment of stroke (CAT-FAS). The CAT-FAS can simultaneously assess four functions (two motor functions [upper and lower extremities], postural control, and basic activities of daily living) with sufficient reliability and administrative efficiency.

Sistema de prueba adaptativa automatizada de valoración funcional del movimiento

The computerized adaptive testing system of the functional assessment of stroke (CAT-FAS) can simultaneously assess four functions (motor functions of the ...

Olfactory Context Dependent Memory: Direct Presentation of Odorants

Information is retrieved more effectively when the retrieval occurs in the same context as that in which the information was first encoded. This is termed context dependent memory (CDM). One category of cues that have been shown to effectively produce CDM effects are odors. However, it is unclear what the boundary conditions of these CDM effects are. In particular, given that olfaction has been called an implicit sense, it is possible that odors are only effective mnemonic cues when they are presented in the background. This assertion seems even more likely given that previous research has shown odors to be poor cues during paired associate memory tests, where odors are in the focus of attention as mnemonic cues for other information. In order to determine whether odors are only effective contextual mnemonic cues when presented outside the central focus of an observer, an olfactory CDM experiment was performed in which odorants were presented directly, rather than ambiently. Direct presentation was accomplished with the aid of an olfactometer. The olfactometer not only allows for direct presentation of odorants, but provides other methodological benefits, including the allowance of trial by trial manipulations of odorant presentations and, relatedly, time-specific releases of odorants. The presence of the same odor during both encoding and retrieval enhanced memory performance, regardless of whether the odor was presented ambiently or directly. This finding can serve as a basis for future olfactory CDM research which can utilize the benefits of direct presentation.

The use of an olfactometer for directly presenting odorants opens exciting opportunities for researchers of olfactory memory. The current paper discusses issues related to this methodology as related to a previously published experiment on olfactory context dependent memory.

Memoria dependiente de contexto olfativa: Presentación directa de olores

Information is retrieved more effectively when the retrieval occurs in the same context as that in which the information was first encoded. This is termed ...

Methods Article

Simple y asistida por ordenador de pruebas olfativas para Ratones