Nous tenons à remercier Eugène Gurfinkel et Mark Chapman pour leur rôle dans la conception et la fabrication de Twister. Le développement de Twister a été financée par les Instituts nationaux de subventions de la santé R01 AR-31 017 à P. et V. Cordo Gurfinkel et F32 HD-008520 à T. Cacciatore. T. Cacciatore tiens également à remercier le Medical Research Council, Royaume-Uni pour le soutien à l&#39;écriture de ce manuscrit.

<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>

Les auteurs n&#39;ont rien à révéler.

Il est de notre avis que Twister peut être utilisé examinera les questions nombreuses dans le contrôle tonique. À ce jour, Twister a conduit à 7 publications telles 6-11,14. Probablement la plus importante caractéristique de Twister est qu&#39;il fournit un système intégré, mesure de cinétique de ton. Cette mesure de couple de ton n&#39;est pas fournie par cinématique, dynamique inverse ou les approches électromyographiques, et est nécessaire pour répondre aux nombreuses questions concernant ton. En outre, Twister est unique en pas sensiblement interférer avec l&#39;antigravité naturel ou comportement postural, et fournit un tonique, plutôt que d&#39;une perturbation phasique. Une utilisation potentielle de twister est la quantification des effets toniques de la maladie sur le tonus postural. Alors que la rigidité intrinsèque et le réflexe a été bien étudié pour de nombreuses maladies neurologiques et musculo-squelettiques en utilisant les perturbations rapide, l&#39;effet quantitatif de nombreuses maladies sur le tonus postural n&#39;est pas bien caractérisée. En particulier, Twister peut être used pour quantifier les effets des troubles tels que la rigidité 7,10,14, hypotonie, dystonie, et douleurs au dos et au cou de l&#39;ampleur, la distribution et la symétrie du tonus postural long de l&#39;axe du corps. Il peut également être utilisé pour mesurer kinesthésie axial, p.ex., la perception de rotation du corps repose sur les propriocepteurs des muscles et la symétrie perceptuomotor 11, par exemple, la représentation de tout droit pendant torsion axiale 14. Enfin, Twister peut être utilisé pour étudier l&#39;effet des interventions sur ces mesures du tonus postural axial 8. Nous estimons le coût de l&#39;embauche une firme d&#39;ingénierie pour fabriquer Twister est d&#39;environ $ 30.000 américains. Cet appareil peut vraisemblablement être fabriqués en interne pour une fraction de ce coût, comme le prix des matières premières est faible, mais significative de fabrication est nécessaire. Tout au long de son utilisation, Twister a beaucoup évolué et continue de le faire. Il ya beaucoup de questions fondamentales qui peuvent être abordés avec Twister. Nous espérons que cetterapport aidera d&#39;autres enquêteurs construire des dispositifs Torsion ou stimuler la recherche dans ce domaine fondamental mais mal compris.

method to measure tone of axial and proximal muscle

Le contrôle de l&#39;activité musculaire tonique reste mal comprise. Si la tonalité anormale est communément évaluée cliniquement par la mesure de la résistance passive des membres détendus 1, pas de systèmes sont disponibles pour étudier le contrôle des muscles toniques dans un état ​​naturel, active de soutien antigravité. Nous avons développé un dispositif (Twister) pour étudier la régulation tonique des muscles axiaux et proximaux lors de l&#39;entretien posturale actifs (c&#39;est à dire la posture la tonalité). Twister tourne régions du corps axiale par rapport à l&#39;autre sur l&#39;axe vertical au cours attitude, afin de tordre les régions cou, du tronc ou de la hanche. Cette torsion impose des changements de longueur axiale sur les muscles sans changer la relation du corps à la gravité. Parce que Twister ne fournit pas de soutien postural, le ton doit être réglementé pour contrecarrer les couples gravitationnels. Nous quantifions ce règlement tonique par le couple rétive à la torsion, ce qui reflète l&#39;état de tous les muscles subissent des changements de longueur, ainsi que par électromyographie demuscles concernés. Parce que le ton est caractérisée par de longue durée l&#39;activité musculaire de faible niveau, le contrôle tonique est étudié avec des mouvements lents qui produisent «tonique» des changements dans la longueur du muscle, sans évoquer rapide &quot;phasique&quot; réponses. Twister peut être reconfiguré pour étudier divers aspects de la tonicité musculaire, comme co-contraction, la modulation tonique pour les changements de posture, des interactions entre les segments du corps tonique, ainsi que les seuils de perception de ralentir la rotation axiale. Twister peut également être utilisé pour fournir une mesure quantitative des effets de la maladie sur le tonus postural axiale et proximale et d&#39;évaluer l&#39;efficacité de l&#39;intervention.

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

Nous avons développé un dispositif (Twister) pour étudier la régulation de l&#39;activité musculaire tonique posturale lors de la maintenance active. Twister mesures de résistance à la torsion et réponses musculaires chez des sujets debout pendant de torsion de l&#39;axe du corps. L&#39;appareil peut être configuré de manière flexible pour étudier divers aspects du contrôle tonique dans le cou, le tronc, et / ou les hanches.

Méthode pour mesurer tonicité des muscles axiaux et proximaux

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 vues.  Oregon Health and Science University. Nous avons développé un dispositif (Twister) pour étudier la régulation de l'activité musculaire tonique posturale lors de la maintenance active. Twister mesures de résistance à la torsion et réponses musculaires chez des sujets debout pendant de torsion de l'axe du corps. L'appareil peut être configuré de manière flexible pour étudier divers aspects du contrôle tonique dans le cou, le tronc, et / ou les hanches.

Vidéo: 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.

Test musculaire manuel: une méthode de mesure la force musculaire des extrémités appliquée aux patients gravement malades

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

Recherche

Médecine

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.

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

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.

Assay Sphéroïde pour mesurer le TGF-β induit 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 ...

Molecular Imaging to Target Transplanted Muscle Progenitor Cells

Duchenne muscular dystrophy (DMD) is a severe genetic neuromuscular disorder that affects 1 in 3,500 boys, and is characterized by progressive muscle degeneration1, 2. In patients, the ability of resident muscle satellite cells (SCs) to regenerate damaged myofibers becomes increasingly inefficient4. Therefore, transplantation of muscle progenitor cells (MPCs)/myoblasts from healthy subjects is a promising therapeutic approach to DMD. A major limitation to the use of stem cell therapy, however, is a lack of reliable imaging technologies for long-term monitoring of implanted cells, and for evaluating its effectiveness. Here, we describe a non-invasive, real-time approach to evaluate the success of myoblast transplantation. This method takes advantage of a unified fusion reporter gene composed of genes (firefly luciferase [fluc], monomeric red fluorescent protein [mrfp] and sr39 thymidine kinase [sr39tk]) whose expression can be imaged with different imaging modalities9, 10. A variety of imaging modalities, including positron emission tomography (PET), single-photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), optical imaging, and high frequency 3D-ultrasound are now available, each with unique advantages and limitations11. Bioluminescence imaging (BLI) studies, for example, have the advantage of being relatively low cost and high-throughput. It is for this reason that, in this study, we make use of the firefly luciferase (fluc) reporter gene sequence contained within the fusion gene and bioluminescence imaging (BLI) for the short-term localization of viable C2C12 myoblasts following implantation into a mouse model of DMD (muscular dystrophy on the X chromosome [mdx] mouse)12-14. Importantly, BLI provides us with a means to examine the kinetics of labeled MPCs post-implantation, and will be useful to track cells repeatedly over time and following migration. Our reporter gene approach further allows us to merge multiple imaging modalities in a single living subject; given the tomographic nature, fine spatial resolution and ability to scale up to larger animals and humans10,11, PET will form the basis of future work that we suggest may facilitate rapid translation of methods developed in cells to preclinical models and to clinical applications.

A non-invasive means to evaluate the success of myoblast transplantation is described. The method takes advantage of a unified fusion reporter gene composed of genes whose expression can be imaged with different imaging modalities. Here, we make use of a fluc reporter gene sequence to target cells via bioluminescence imaging.

L&#39;imagerie moléculaire à la cible transplanté des cellules progénitrices musculaires

Duchenne muscular dystrophy (DMD) is a severe genetic neuromuscular disorder that affects 1 in 3,500 boys, and is characterized by progressive muscle ...

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.

Haut-débit cytométrie en flux test cellulaire pour détecter les anticorps de la N-méthyl-D-aspartate Receptor ou récepteur de la dopamine-2 dans le sérum humain

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

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.

Précision en médecine dentaire, une nouvelle façon de mesurer la justesse et fidélité

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.

Vessie muscle lisse bande de contractilité comme une méthode pour évaluer urinaires inférieures Pharmacologie

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.

Détection précoce du médicament-Induced rénale hémodynamique Dysfonction Utilisation de échographique Technology chez le rat

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.

Télémétrie intra-utérine mesurer souris contractile pression<em&gt; In 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.

Évaluation Basé échographie de l&#39;artère coronaire de débit et de Flow Reserve coronaire Utilisation de la surcharge de pression modèle chez la souris

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

In Vivo Evaluation of the Mechanical and Viscoelastic Properties of the Rat Tongue

The tongue is a highly innervated and vascularized muscle hydrostat on the floor of the mouth of most vertebrates. Its primary functions include supporting mastication and deglutition, as well as taste-sensing and phonetics. Accordingly, the strength and volume of the tongue can impact the ability of vertebrates to accomplish basic activities such as feeding, communicating, and breathing. Human patients with sleep apnea have enlarged tongues, characterized by reduced muscle tone and increased intramuscular fat that can be visualized and quantified by magnetic resonance imaging (MRI). The abilities to measure force generation and viscoelastic properties of the tongue constitute important tools for obtaining functional information to correlate with imaging data. Here, we present techniques for measuring tongue force production in anesthetized Zucker rats via electrical stimulation of the hypoglossal nerves and for determining the viscoelastic properties of the tongue by applying passive Lissajous force/deformation curves.

In Vivo Evaluation of the Mechanical and Viscoelastic Properties of the Rat Tongue

We describe a surgical procedure in an anesthetized rat model for determining the muscle tone and viscoelastic properties of the tongue. The procedure involves specific stimulation of the hypoglossal nerves and application of passive Lissajous force/deformation curves to the muscle.