Nos gustaría dar las gracias a Eugene Gurfinkel y Chapman Marcos por su participación en el diseño y la fabricación de Twister. El desarrollo de Twister fue financiado por los Institutos Nacionales de Salud subvenciones R01 AR-31017 de P. Gurfinkel y Cordo V. y F32 HD-008520 de T. Cacciatore. T. Cacciatore también desea agradecer el Medical Research Council, del Reino Unido para apoyar a escribir este manuscrito.

<ol>
	<li>Foster, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Text+Book+of+Physiology.">A Text Book of Physiology.</a> The Central Nervous System. Vol. III, (1892).</li><li>Zatsiorsky, V. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kinetics+of+human+motion.">Kinetics of human motion.</a> Human Kinetics. , (2002).</li><li>Kumar, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ergonomics+and+biology+of+spinal+rotation.">Ergonomics and biology of spinal rotation.</a> Ergonomics. 47, 370-415 (2004).</li><li>Kumar, S., Panjabi, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vivo+axial+rotations+and+neutral+zones+of+the+thoracolumbar+spine.">Vivo axial rotations and neutral zones of the thoracolumbar spine.</a> Journal of spinal. 8, 253-263 (1995).</li><li>Lamoth, C. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pelvis-thorax+coordination+in+the+transverse+plane+during+walking+in+persons+with+nonspecific+low+back.">Pelvis-thorax coordination in the transverse plane during walking in persons with nonspecific low back.</a> Spine. 27, E92-E99 (2002).</li><li>Gurfinkel, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Postural+muscle+tone+in+the+body+axis+of+healthy+humans.">Postural muscle tone in the body axis of healthy humans.</a> Journal of Neurophysiology. 96, 2678-2687 (2006).</li><li>Wright, W. G., Gurfinkel, V. S., Nutt, J., Horak, F. B., Cordo, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Axial+hypertonicity+in+Parkinson's+disease:+direct+measurements+of+trunk+and+hip+torque.">Axial hypertonicity in Parkinson's disease: direct measurements of trunk and hip torque.</a> Exp. Neurol. 208, 38-46 (2007).</li><li>Cacciatore, T. W., Gurfinkel, V. S., Horak, F. B., Cordo, P. J., Ames, K. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Increased+dynamic+regulation+of+postural+tone+through+Alexander+Technique+training.">Increased dynamic regulation of postural tone through Alexander Technique training.</a> Human movement science. 30, 74-89 (2011).</li><li>Franzen, E., Gurfinkel, V. S., Wright, W. G., Cordo, P. J., Horak, F. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Haptic+touch+reduces+sway+by+increasing+axial+tone.">Haptic touch reduces sway by increasing axial tone.</a> Neuroscience. 174, 216-223 (2011).</li><li>Franzen, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reduced+performance+in+balance,+walking+and+turning+tasks+is+associated+with+increased+neck+tone+in+Parkinson's+disease.">Reduced performance in balance, walking and turning tasks is associated with increased neck tone in Parkinson's disease.</a> Exp. Neurol. 219, 430-438 (2009).</li><li>Wright, W. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Axial+kinesthesia+is+impaired+in+Parkinson's+disease:+Effects+of+levodopa.">Axial kinesthesia is impaired in Parkinson's disease: Effects of levodopa.</a> Exp. Neurol. , (2010).</li><li>Sinkjaer, T., Toft, E., Andreassen, S., Hornemann, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Muscle+stiffness+in+human+ankle+dorsiflexors:+intrinsic+and+reflex+components.">Muscle stiffness in human ankle dorsiflexors: intrinsic and reflex components.</a> J Neurophysiol. 60, 1110-1121 (1988).</li><li>Sherrington, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+plastic+tonus+and+proprioceptive+reflexes.">On plastic tonus and proprioceptive reflexes.</a> Quart. J. Exper. Physiol. 2, 109-156 (1909).</li><li>Wright, W. G., Gurfinkel, V., King, L., Horak, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Parkinson's+disease+shows+perceptuomotor+asymmetry+unrelated+to+motor+symptoms.">Parkinson's disease shows perceptuomotor asymmetry unrelated to motor symptoms.</a> Neurosci. Lett. 417, 10-15 (2007).</li></ol>

Los autores no tienen nada que revelar.

Es nuestra opinión que Twister se puede utilizar preguntas frente a muchos en el control tónico. Hasta la fecha, Twister ha dado lugar a siete publicaciones 6-11,14. Probablemente la característica más importante de Twister es que proporciona una medida integrada, cinética de tono. Esta medida del par de tono no es proporcionada por la dinámica de cinemática, inversa o métodos electromiográficos, y es necesario responder a muchas preguntas sobre el tono. Además, Twister es único en no interferir considerablemente con la antigravedad o el comportamiento natural de la postura, y proporciona un tónico, en lugar de una perturbación fásica. Un uso potencial de tornado es la cuantificación de los efectos tónicos de la enfermedad en el tono postural. Mientras que la rigidez intrínseca y el reflejo ha sido bien estudiado por muchos trastornos neurológicos y músculo-esquelético con perturbaciones rápido, no el efecto cuantitativo de muchas enfermedades en el tono postural bien caracterizados. En particular, Twister puede ser used para cuantificar los efectos de trastornos como la rigidez de 7,10,14, hipotonía, distonía, y dolor de espalda y cuello sobre la magnitud, distribución y la simetría del tono postural a lo largo del eje del cuerpo. También puede ser usado para medir la cinestesia axial, por ejemplo, la percepción de la rotación del cuerpo sobre la base de propioceptores musculares y el 11 de simetría perceptuomotor, por ejemplo, la representación de recto durante torsión axial 14. Por último, Twister se puede utilizar para estudiar el efecto de la intervención sobre estas medidas en el tono postural axial 8. Estimamos que el costo de contratar a una empresa de ingeniería para la fabricación de Twister es de aproximadamente 30.000 dólares EE.UU.. Este dispositivo es probable se pueden fabricar en casa por una fracción de este costo, ya que el precio de las materias primas es bajo, pero significativo de fabricación se requiere. A lo largo de su uso, Twister ha evolucionado considerablemente y lo sigue haciendo. Hay muchas preguntas básicas que se pueden abordar con Twister. Esperamos que estainforme ayudará a los investigadores a otros a construir dispositivos de torsión o de otra manera estimular la investigación en esta área fundamental pero mal entendido.

method to measure tone of axial and proximal muscle

El control de la actividad muscular tónica sigue siendo poco conocida. Mientras que el tono anormal es comúnmente evaluados clínicamente mediante la medición de la resistencia pasiva de los miembros se relajaron 1, no se dispone de sistemas para estudiar el control muscular tónica en un estado natural, activa de apoyo a la antigravedad. Hemos desarrollado un dispositivo (Twister) para estudiar la regulación tónica de los músculos axiales y proximales en activo de mantenimiento postural (es decir, el tono postural). Twister gira regiones axiales del cuerpo respecto al otro alrededor del eje vertical en la posición, así como para torcer la región del cuello, el tronco o la cadera. Esta torsión impone cambios en la longitud axial en los músculos sin necesidad de cambiar la relación del cuerpo con la gravedad. Debido a Twister no ofrece soporte postural, el tono debe ser regulada para contrarrestar pares gravitacionales. Podemos cuantificar esta regulación tónico por el par de inquietos a la torsión, lo que refleja el estado de todos los músculos sometidos a cambios en la longitud, así como por electromiografía delos músculos correspondientes. Porque el tono se caracteriza por la larga duración la actividad muscular de bajo nivel, el control tónico es estudiado con movimientos lentos que producen &quot;tónica&quot; los cambios en la longitud muscular, sin despertar rápido &quot;fásico&quot; las respuestas. Twister se puede reconfigurar para estudiar diversos aspectos del tono muscular, como por ejemplo, la co-contracción de modulación tónico para los cambios posturales, las interacciones tónica en todos los segmentos del cuerpo, así como los umbrales de la percepción para reducir la rotación axial. Twister también se puede utilizar para proporcionar una medición cuantitativa de los efectos de la enfermedad en el tono postural axial y proximal y evaluar la eficacia de la intervención.

Watch this Scientific Journal Video about Method to Measure Tone of Axial and Proximal Muscle at JoVE.com

Method to Measure Tone of Axial and Proximal Muscle

Hemos desarrollado un dispositivo (Twister) para estudiar la regulación de la actividad tónica muscular postural durante el mantenimiento activo. Twister medidas de resistencia a la torsión y la respuesta muscular en los sujetos de pie durante la torsión del eje del cuerpo. El dispositivo puede configurarse de manera flexible para estudiar diversos aspectos del control tónico en el cuello, tronco y / o las caderas.

Método para medir el tono del músculo axial y proximal

The control of tonic muscular activity remains poorly understood.  While abnormal tone is commonly assessed clinically by measuring the passive resistance ...

method-to-measure-tone-of-axial-and-proximal-muscle

Research

JoVE Journal

Medicine

17.4K vistas.  Oregon Health and Science University. Hemos desarrollado un dispositivo (Twister) para estudiar la regulación de la actividad tónica muscular postural durante el mantenimiento activo. Twister medidas de resistencia a la torsión y la respuesta muscular en los sujetos de pie durante la torsión del eje del cuerpo. El dispositivo puede configurarse de manera flexible para estudiar diversos aspectos del control tónico en el cuello, tronco y / o las caderas.

Video: Method to Measure Tone of Axial and Proximal Muscle

Manual Muscle Testing:  A Method of Measuring Extremity Muscle Strength Applied to Critically Ill Patients

Survivors of acute respiratory distress syndrome (ARDS) and other causes of critical illness often have generalized weakness, reduced exercise tolerance, and persistent nerve and muscle impairments after hospital discharge.1-6 Using an explicit protocol with a structured approach to training and quality assurance of research staff, manual muscle testing (MMT) is a highly reliable method for assessing strength, using a standardized clinical examination, for patients following ARDS, and can be completed with mechanically ventilated patients who can tolerate sitting upright in bed and are able to follow two-step commands. 7, 8 
This video demonstrates a protocol for MMT, which has been taught to &ge;43 research staff who have performed &gt;800 assessments on &gt;280 ARDS survivors. Modifications for the bedridden patient are included. Each muscle is tested with specific techniques for positioning, stabilization, resistance, and palpation for each score of the 6-point ordinal Medical Research Council scale.7,9-11 Three upper and three lower extremity muscles are graded in this protocol: shoulder abduction, elbow flexion, wrist extension, hip flexion, knee extension, and ankle dorsiflexion. These muscles were chosen based on the standard approach for evaluating patients for ICU-acquired weakness used in prior publications. 1,2.

Survivors of acute respiratory distress syndrome (ARDS) and critical illness frequently develop long-lasting muscle weakness. Manual muscle testing (MMT) is a standardized clinical examination commonly used to measure strength of peripheral skeletal muscle groups. This video demonstrates MMT using the 6-point Medical Research Council scale.

Pruebas musculares manuales: un método para medir fuerza de las extremidades muscular aplicada a los pacientes críticos

Survivors of acute respiratory distress syndrome (ARDS) and other causes of critical illness often have generalized weakness, reduced exercise tolerance, ...

Investigación

Medicina

Spheroid Assay to Measure TGF-&#946;-induced Invasion

TGF-&beta; has opposing roles in breast cancer progression by acting as a tumor suppressor in the initial phase, but stimulating invasion and metastasis at later stage1,2. Moreover, TGF-&beta; is frequently overexpressed in breast cancer and its expression correlates with poor prognosis and metastasis 3,4. The mechanisms by which TGF-&beta; induces invasion are not well understood.
TGF-&beta; elicits its cellular responses via TGF-&beta; type II (T&beta;RII) and type I (T&beta;RI) receptors. Upon TGF-&beta;-induced heteromeric complex formation, T&beta;RII phosphorylates the T&beta;RI. The activated T&beta;RI initiates its intracellular canonical signaling pathway by phosphorylating receptor Smads (R-Smads), i.e. Smad2 and Smad3. These activated R-Smads form heteromeric complexes with Smad4, which accumulate in the nucleus and regulate the transcription of target genes5. In addition to the previously described Smad pathway, receptor activation results in activation of several other non-Smad signaling pathways, for example Mitogen Activated Protein Kinase (MAPK) pathways6.
To study the role of TGF-&beta; in different stages of breast cancer, we made use of the MCF10A cell system. This system consists of spontaneously immortalized MCF10A1 (M1) breast epithelial cells7, the H-RAS transformed M1-derivative MCF10AneoT (M2), which produces premalignant lesions in mice8, and the M2-derivative MCF10CA1a (M4), which was established from M2 xenografts and forms high grade carcinomas with the ability to metastasize to the lung9. This MCF10A series offers the possibility to study the responses of cells with different grades of malignancy that are not biased by a different genetic background.
For the analysis of TGF-&beta;-induced invasion, we generated homotypic MCF10A spheroid cell cultures embedded in a 3D collagen matrix in vitro (Fig 1). Such models closely resemble human tumors in vivo by establishing a gradient of oxygen and nutrients, resulting in active and invasive cells on the outside and quiescent or even necrotic cells in the inside of the spheroid10. Spheroid based assays have also been shown to better recapitulate drug resistance than monolayer cultures11. This MCF10 3D model system allowed us to investigate the impact of TGF-&beta; signaling on the invasive properties of breast cells in different stages of malignancy.

An assay to quantitatively measure Transforming Growth Factor (TGF)-&#x03B2;-induced invasion in 3-dimensional collagen gels is described. This assay takes advantage of the MCF10A series of cell lines, which represent different stages of breast cancer development. This method can be adopted to be used with other cell lines and might be used to investigate other potential activators or inhibitors of invasion.

Ensayo esferoide para medir TGF-β inducida por invasión

TGF-&beta; has opposing roles in breast cancer progression by acting as a tumor suppressor in the initial phase, but stimulating invasion and metastasis ...

The Measurement and Treatment of Suppression in Amblyopia

Amblyopia, a developmental disorder of the visual cortex, is one of the leading causes of visual dysfunction in the working age population. Current estimates put the prevalence of amblyopia at approximately 1-3%1-3, the majority of cases being monocular2. Amblyopia is most frequently caused by ocular misalignment (strabismus), blur induced by unequal refractive error (anisometropia), and in some cases by form deprivation.
Although amblyopia is initially caused by abnormal visual input in infancy, once established, the visual deficit often remains when normal visual input has been restored using surgery and/or refractive correction. This is because amblyopia is the result of abnormal visual cortex development rather than a problem with the amblyopic eye itself4,5 . Amblyopia is characterized by both monocular and binocular deficits6,7 which include impaired visual acuity and poor or absent stereopsis respectively. The visual dysfunction in amblyopia is often associated with a strong suppression of the inputs from the amblyopic eye under binocular viewing conditions8. Recent work has indicated that suppression may play a central role in both the monocular and binocular deficits associated with amblyopia9,10 .
Current clinical tests for suppression tend to verify the presence or absence of suppression rather than giving a quantitative measurement of the degree of suppression. Here we describe a technique for measuring amblyopic suppression with a compact, portable device11,12 . The device consists of a laptop computer connected to a pair of virtual reality goggles. The novelty of the technique lies in the way we present visual stimuli to measure suppression. Stimuli are shown to the amblyopic eye at high contrast while the contrast of the stimuli shown to the non-amblyopic eye are varied. Patients perform a simple signal/noise task that allows for a precise measurement of the strength of excitatory binocular interactions. The contrast offset at which neither eye has a performance advantage is a measure of the "balance point" and is a direct measure of suppression. This technique has been validated psychophysically both in control13,14 and patient6,9,11 populations.
In addition to measuring suppression this technique also forms the basis of a novel form of treatment to decrease suppression over time and improve binocular and often monocular function in adult patients with amblyopia12,15,16 . This new treatment approach can be deployed either on the goggle system described above or on a specially modified iPod touch device15.

Amblyopia is a developmental disorder of the visual cortex that is often accompanied by strong suppression of one eye. We present a new technique for measuring and treating interocular suppression in patients with amblyopia that can be deployed using virtual reality goggles or a portable iPod Touch device.

La medición y tratamiento de la represión en la ambliopía

Amblyopia, a developmental disorder of the visual cortex, is one of the leading causes of visual dysfunction in the working age population. Current ...

High-throughput Flow Cytometry Cell-based Assay to Detect Antibodies to N-Methyl-D-aspartate Receptor or Dopamine-2 Receptor in Human Serum

Over the recent years, antibodies against surface and conformational proteins involved in neurotransmission have been detected in autoimmune CNS diseases in children and adults. These antibodies have been used to guide diagnosis and treatment. Cell-based assays have improved the detection of antibodies in patient serum. They are based on the surface expression of brain antigens on eukaryotic cells, which are then incubated with diluted patient sera followed by fluorochrome-conjugated secondary antibodies. After washing, secondary antibody binding is then analyzed by flow cytometry. Our group has developed a high-throughput flow cytometry live cell-based assay to reliably detect antibodies against specific neurotransmitter receptors. This flow cytometry method is straight forward, quantitative, efficient, and the use of a high-throughput sampler system allows for large patient cohorts to be easily assayed in a short space of time. Additionally, this cell-based assay can be easily adapted to detect antibodies to many different antigenic targets, both from the central nervous system and periphery. Discovering additional novel antibody biomarkers will enable prompt and accurate diagnosis and improve treatment of immune-mediated disorders.

Over the recent years, live cell-based assays have been used successfully to detect antibodies against surface and conformational antigens. Here, we describe a method using high-throughput flow cytometry enabling the analysis of large cohorts of patients. Detection of novel antibodies will improve diagnosis and treatment of immune-mediated disorders.

Ensayo de alto rendimiento basado en células citometría de flujo para detectar anticuerpos a la N-metil-D-aspartato receptor o dopamina-2 del receptor en suero humano

Over the recent years, antibodies against surface and conformational proteins involved in neurotransmission have been detected in autoimmune CNS diseases ...

Assessment of Right Ventricular Structure and Function in Mouse Model of Pulmonary Artery Constriction by Transthoracic Echocardiography

Emerging clinical data support the notion that RV dysfunction is critical to the pathogenesis of cardiovascular disease and heart failure1-3. Moreover, the RV is significantly affected in pulmonary diseases such as pulmonary artery hypertension (PAH). In addition, the RV is remarkably sensitive to cardiac pathologies, including left ventricular (LV) dysfunction, valvular disease or RV infarction4. To understand the role of RV in the pathogenesis of cardiac diseases, a reliable and noninvasive method to access the RV structurally and functionally is essential.
A noninvasive trans-thoracic echocardiography (TTE) based methodology was established and validated for monitoring dynamic changes in RV structure and function in adult mice. To impose RV stress, we employed a surgical model of pulmonary artery constriction (PAC) and measured the RV response over a 7-day period using a high-frequency ultrasound microimaging system. Sham operated mice were used as controls. Images were acquired in lightly anesthetized mice at baseline (before surgery), day 0 (immediately post-surgery), day 3, and day 7 (post-surgery). Data was analyzed offline using software.
Several acoustic windows (B, M, and Color Doppler modes), which can be consistently obtained in mice, allowed for reliable and reproducible measurement of RV structure (including RV wall thickness, end-diastolic&#160;and end-systolic dimensions), and function (fractional area change, fractional shortening, PA peak velocity, and peak pressure gradient) in normal mice and following PAC.
Using this method, the pressure-gradient resulting from PAC was accurately measured in real-time using Color Doppler mode and was comparable to direct pressure measurements performed with a Millar high-fidelity microtip catheter. Taken together, these data demonstrate that RV measurements obtained from various complimentary views using echocardiography are reliable, reproducible and can provide insights regarding RV structure and function. This method will enable a better understanding of the role of RV cardiac dysfunction.

Right ventricle (RV) dysfunction is critical to the pathogenesis of cardiovascular disease, yet limited methodologies are available for its evaluation. Recent advances in ultrasound imaging provide a noninvasive and accurate option for longitudinal RV study. Herein, we detail a step-by-step echocardiographic method using a murine model of RV pressure overload.

Evaluación del ventrículo derecho Estructura y función en modelo de ratón de la constricción de la arteria pulmonar mediante ecocardiografía transtorácica

Emerging clinical data support the notion that RV dysfunction is critical to the pathogenesis of cardiovascular disease and heart failure1-3. Moreover, ...

Accuracy in Dental Medicine, A New Way to Measure Trueness and Precision

Reference scanners are used in dental medicine to verify a lot of procedures. The main interest is to verify impression methods as they serve as a base for dental restorations. The current limitation of many reference scanners is the lack of accuracy scanning large objects like full dental arches, or the limited possibility to assess detailed tooth surfaces. A new reference scanner, based on focus variation scanning technique, was evaluated with regards to highest local and general accuracy. A specific scanning protocol was tested to scan original tooth surface from dental impressions. Also, different model materials were verified. The results showed a high scanning accuracy of the reference scanner with a mean deviation of 5.3 &#177; 1.1 &#181;m for trueness and 1.6 &#177; 0.6 &#181;m for precision in case of full arch scans. Current dental impression methods showed much higher deviations (trueness: 20.4 &#177; 2.2 &#181;m, precision: 12.5 &#177; 2.5 &#181;m) than the internal scanning accuracy of the reference scanner. Smaller objects like single tooth surface can be scanned with an even higher accuracy, enabling the system to assess erosive and abrasive tooth surface loss. The reference scanner can be used to measure differences for a lot of dental research fields. The different magnification levels combined with a high local and general accuracy can be used to assess changes of single teeth or restorations up to full arch changes.

Accuracy is a major demand in dental medicine. To verify accuracy, reference scanners are needed. This article presents a new reference scanner with an adjusted scanning method to acquire a broad variety of dental morphologies with high trueness and precision.

Precisión en Medicina Dental, Una nueva forma de medir veracidad y precisión

Reference scanners are used in dental medicine to verify a lot of procedures. The main interest is to verify impression methods as they serve as a base ...

Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology

We describe an in vitro method to measure bladder smooth muscle contractility, and its use for investigating physiological and pharmacological properties of the smooth muscle as well as changes induced by pathology. This method provides critical information for understanding bladder function while overcoming major methodological difficulties encountered in in vivo experiments, such as surgical and pharmacological manipulations that affect stability and survival of the preparations, the use of human tissue, and/or the use of expensive chemicals. It also provides a way to investigate the properties of each bladder component (i.e. smooth muscle, mucosa, nerves) in healthy and pathological conditions.
The urinary bladder is removed from an anesthetized animal, placed in Krebs solution and cut into strips. Strips are placed into a chamber filled with warm Krebs solution. One end is attached to an isometric tension transducer to measure contraction force, the other end is attached to a fixed rod. Tissue is stimulated by directly adding compounds to the bath or by electric field stimulation electrodes that activate nerves, similar to triggering bladder contractions in vivo. We demonstrate the use of this method to evaluate spontaneous smooth muscle contractility during development and after an experimental spinal cord injury, the nature of neurotransmission (transmitters and receptors involved), factors involved in modulation of smooth muscle activity, the role of individual bladder components, and species and organ differences in response to pharmacological agents. Additionally, it could be used for investigating intracellular pathways involved in contraction and/or relaxation of the smooth muscle, drug structure-activity relationships and evaluation of transmitter release.
The in vitro smooth muscle contractility method has been used extensively for over 50 years, and has provided data that significantly contributed to our understanding of bladder function as well as to pharmaceutical development of compounds currently used clinically for bladder management.

This manuscript presents a simple, yet powerful, in vitro method for evaluating smooth muscle contractility in response to pharmacological agents or nerve stimulation. Main applications are drug screening and understanding tissue physiology, pharmacology,&#160;and pathology.

Vejiga contractilidad del músculo liso de Gaza como un método para evaluar tracto urinario inferior Farmacología

We describe an in vitro method to measure bladder smooth muscle contractility, and its use for investigating physiological and pharmacological properties ...

Early Detection of Drug-Induced Renal Hemodynamic Dysfunction Using Sonographic Technology in Rats

The kidney normally functions to maintain hemodynamic homeostasis and is a major site of damage caused by drug toxicity. Drug-induced nephrotoxicity is estimated to contribute to 19- 25% of all clinical cases of acute kidney injury (AKI) in critically ill patients. AKI detection has historically relied on metrics such as serum creatinine (sCr) or blood urea nitrogen (BUN) which are demonstrably inadequate in full assessment of nephrotoxicity in the early phase of renal dysfunction. Currently, there is no robust diagnostic method to accurately detect hemodynamic alteration in the early phase of AKI while such alterations might actually precede the rise in serum biomarker levels. Such early detection can help clinicians make an accurate diagnosis and help in in decision making for therapeutic strategy. Rats were treated with Cisplatin to induce AKI. Nephrotoxicity was assessed for six days using high-frequency sonography, sCr measurement and upon histopathology of kidney. Hemodynamic evaluation using 2D and Color-Doppler images were used to serially study nephrotoxicity in rats, using the sonography. Our data showed successful drug-induced kidney injury in adult rats by histological examination. Color-Doppler based sonographic assessment of AKI indicated that resistive-index (RI) and pulsatile-index (PI) were increased in the treatment group; and peak-systolic velocity (mm/s), end-diastolic velocity (mm/s) and velocity-time integral (VTI, mm) were decreased in renal arteries in the same group. Importantly, these hemodynamic changes evaluated by sonography preceded the rise of sCr levels. Sonography-based indices such as RI or PI can thus be useful predictive markers of declining renal function in rodents. From our sonography-based observations in the kidneys of rats that underwent AKI, we showed that these noninvasive hemodynamic measurements may consider as an accurate, sensitive and robust method in detecting early stage kidney dysfunction. This study also underscores the importance of ethical issues associated with animal use in research.

Early stage hemodynamic dysfunction is critical to the development of kidney disease. Yet, detection methodologies are limited. Recent advances in sonography provide a noninvasive, accurate option for early detection of kidney injury. This study outlines a step-by-step, sonographic methodology for detecting kidney dysfunction using a drug-induced nephrotoxicity rat model.

La detección precoz de la disfunción renal hemodinámico inducido por medicamentos Usando tecnología ecográfica en ratas

The kidney normally functions to maintain hemodynamic homeostasis and is a major site of damage caused by drug toxicity. Drug-induced nephrotoxicity is ...

Intrauterine Telemetry to Measure Mouse Contractile Pressure In Vivo

A complex integration of molecular and electrical signals is needed to transform a quiescent uterus into a contractile organ at the end of pregnancy. Despite the discovery of key regulators of uterine contractility, this process is still not fully understood. Transgenic mice provide an ideal model in which to study parturition. Previously, the only method to study uterine contractility in the mouse was ex vivo isometric tension recordings, which are suboptimal for several reasons. The uterus must be removed from its physiological environment, a limited time course of investigation is possible, and the mice must be sacrificed. The recent development of radiometric telemetry has allowed for longitudinal, real-time measurements of in vivo intrauterine pressure in mice. Here, the implantation of an intrauterine telemeter to measure pressure changes in the mouse uterus from mid-pregnancy until delivery is described. By comparing differences in pressures between wild type and transgenic mice, the physiological impact of a gene of interest can be elucidated. This technique should expedite the development of therapeutics used to treat myometrial disorders during pregnancy, including preterm labor.

Intrauterine Telemetry to Measure Mouse Contractile Pressure In Vivo

This manuscript provides a protocol for implanting telemeters in the mouse for the purpose of measuring intrauterine pressures during pregnancy.

Telemetría intrauterina para medir la presión del ratón contráctil<em&gt; En Vivo</em

A complex integration of molecular and electrical signals is needed to transform a quiescent uterus into a contractile organ at the end of pregnancy. ...

Ultrasound Based Assessment of Coronary Artery Flow and Coronary Flow Reserve Using the Pressure Overload Model in Mice

Transthoracic Doppler echocardiography (TTDE) is a clinically useful, noninvasive tool for studying coronary artery flow velocity and coronary flow reserve (CFR) in humans. Reduced CFR is accompanied by marked intramyocardial and pericoronary fibrosis and is used as an indication of the severity of dysfunction. This study explores, step-by-step, the real-time changes measured in the coronary flow velocity, CFR and systolic to diastolic peak velocity (S/D) ratio in the setting of an aortic banding model in mice. By using a Doppler transthoracic imaging technique that yields reproducible and reliable data, the method assesses changes in flow in the septal coronary artery (SCA), for a period of over two weeks in mice, that previously either underwent aortic banding or thoracotomy. 
During imaging, hyperemia in all mice was induced by isoflurane, an anesthetic that increased coronary flow velocity when compared with resting flow. All images were acquired by a single imager. Two ratios, (1) CFR, the ratio between hyperemic and baseline flow velocities, and (2) systolic (S) to diastolic (D) flow were determined, using a proprietary software and by two independent observers. Importantly, the observed changes in coronary flow preceded LV dysfunction as evidenced by normal LV mass and fractional shortening (FS). 
The method was benchmarked against the current gold standard of coronary assessment, histopathology. The latter technique showed clear pathologic changes in the coronary artery in the form of peri-coronary fibrosis that correlated to the flow changes as assessed by echocardiography. 
The study underscores the value of using a non-invasive technique to monitor coronary circulation in mouse hearts. The method minimizes redundant use of research animals and demonstrates that advanced ultrasound-based indices, such as CFR and S/D ratios, can serve as viable diagnostic tools in a variety of investigational protocols including drug studies and the study of genetically modified strains.

Coronary flow reserve (CFR) is useful for assessment of myocardial oxygen demand and evaluation of cardiovascular risk. This study establishes a step-by-step transthoracic Doppler echocardiographic (TTDE) method for longitudinal monitoring of the changes in CFR, as measured from coronary artery in mice, under the experimental pressure overload of aortic banding.

Evaluación Ultrasonido base de la arteria coronaria de flujo y la reserva coronaria Utilizando la sobrecarga Modelo Presión en ratones

Transthoracic Doppler echocardiography (TTDE) is a clinically useful, noninvasive tool for studying coronary artery flow velocity and coronary flow ...