National Institutes of Health (NIH), Joshua Frase Fondation, Muscular Dystrophy Association (MDA).

<ol>
	<li>Childers, M. K., Okamura, C. S., Bogan, D. J., Bogan, J. R., Petroski, G. F., McDonald, K., Kornegay, J. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Eccentric+contraction+injury+in+dystrophic+canine+muscle.">Eccentric contraction injury in dystrophic canine muscle.</a> Arch Phys Med Rehabil. 83, 1572-1578 (2002).</li><li>Childers, M. K., Okamura, C. S., Bogan, D. J., Bogan, J. R., Sullivan, M. J., Kornegay, J. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Myofiber+injury+and+regeneration+in+a+canine+homologue+of+Duchenne+muscular+dystrophy.">Myofiber injury and regeneration in a canine homologue of Duchenne muscular dystrophy.</a> Am J Phys Med Rehabil. 80, 175-181 (2001).</li><li>MK, C. h. i. l. d. e. r. s., JT, S. t. a. l. e. y., JN, K. o. r. n. e. g. a. y., KS, M. c. D. o. n. a. l. d. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Skinned+single+fibers+from+normal+and+dystrophin-deficient+dogs+incur+comparable+stretch-induced+force+deficits.">Skinned single fibers from normal and dystrophin-deficient dogs incur comparable stretch-induced force deficits.</a> Muscle Nerve. 31, 768-771 (2005).</li><li>Kornegay, J. N., Bogan, D. J., Bogan, J. R., Childers, M. K., Cundiff, D. D., Petroski, G. F., Schueler, R. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Contraction+force+generated+by+tarsal+joint+flexion+and+extension+in+dogs+with+golden+retriever+muscular+dystrophy.">Contraction force generated by tarsal joint flexion and extension in dogs with golden retriever muscular dystrophy.</a> J Neurol Sci. 166, 115-121 (1999).</li><li>Liu, J. M., Okamura, C. S., Bogan, D. J., Bogan, J. R., Childers, M. K., Kornegay, J. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+prednisone+in+canine+muscular+dystrophy.">Effects of prednisone in canine muscular dystrophy.</a> Muscle Nerve. 30, 767-773 (2004).</li><li>Tegeler, C. J., Grange, R. W., Bogan, D. J., Markert, C. D., Case, D., Kornegay, J. N., Childers, M. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Eccentric+contractions+induce+rapid+isometric+torque+drop+in+dystrophin-deficient+dogs.">Eccentric contractions induce rapid isometric torque drop in dystrophin-deficient dogs.</a> Muscle Nerve. 42, 130-132 (2010).</li><li>Allen, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Eccentric+muscle+damage:+mechanisms+of+early+reduction+of+force.">Eccentric muscle damage: mechanisms of early reduction of force.</a> Acta Physiol Scand. 171, 311-319 (2001).</li><li>Friden, J., Lieber, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Eccentric+exercise-induced+injuries+to+contractile+and+cytoskeletal+muscle+fibre+components.">Eccentric exercise-induced injuries to contractile and cytoskeletal muscle fibre components.</a> Acta Physiol Scand. 171, 321-326 (2001).</li><li>Merkies, I. S., Faber, C. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Outcome+measures+in+Duchenne+muscular+dystrophy:+are+we+ready+for+the+new+therapeutic+era?.">Outcome measures in Duchenne muscular dystrophy: are we ready for the new therapeutic era?.</a> Neuromuscul Disord. 19, 447-447 (2009).</li><li>Nagaraju, K., Willmann, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Developing+standard+procedures+for+murine+and+canine+efficacy+studies+of+DMD+therapeutics:+report+of+two+expert+workshops+on+"Pre-clinical+testing+for+Duchenne+dystrophy".">Developing standard procedures for murine and canine efficacy studies of DMD therapeutics: report of two expert workshops on "Pre-clinical testing for Duchenne dystrophy".</a> Neuromuscul Disord. 19, 502-506 (2009).</li><li>Proske, U., Allen, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Damage+to+skeletal+muscle+from+eccentric+exercise.">Damage to skeletal muscle from eccentric exercise.</a> Exerc Sport Sci Rev. 33, 98-104 (2005).</li><li>Warren, G. L., Lowe, D. A., Armstrong, R. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurement+tools+used+in+the+study+of+eccentric+contraction-induced+injury.">Measurement tools used in the study of eccentric contraction-induced injury.</a> Sports Med. 27, 43-59 (1999).</li></ol>

La production de cette vidéo article a été parrainé par Aurora Scientific, Inc

Ce protocole est utilisé pour évaluer la fonction du muscle grand animal in vivo afin d&#39;analyser, documenter et déterminer l&#39;efficacité des interventions thérapeutiques ou pour documenter les caractéristiques biologiques de la progression de la maladie. 1-6 positionnement des animaux, le placement des membres et le placement des électrodes sont des variables clés que les résultats d&#39;impact de manière significative. Dans une étude préliminaire, la moyenne de concentration alvéolaire (MAC) des valeurs pour l&#39;isoflurane n&#39;a pas affecté significativement les mesures de force (RO Schueler, Koch H, Kornegay JN, données inédites, 1993). Matériels et logiciels sont disponibles dans le commerce et les méthodes bien établies. 7, 1,2,8,4,9-11,6,12 Il est recommandé que les utilisateurs d&#39;obtenir et d&#39;utiliser le logiciel et le matériel décrit ci-dessus en suivant ce protocole. Modifications: limitations du servomoteur actuelles comprennent la masse corporelle d&#39;environ 23 kg et une longueur de patte de 20cm. Notez que la limite de couple est ~ 8 N-mètres pour le capteur de couple (modèle 310LR) décrites ici. Cette valeur peut être dépassée par des chiens normaux à 6 mois ou plus. D&#39;éventuelles modifications à l&#39;actuel protocole comprennent la mise à jour du logiciel et d&#39;augmenter la plage de couple du transducteur. Aurora Scientific fabrique un dispositif de positionnement des membres pour les grands animaux qui peuvent être substitués pour le cadre stéréotaxique utilisé dans le protocole actuel. Cette méthode a été appliquée avec succès à d&#39;autres modèles animaux, y compris les primates non-humains.

<table border="1"><tbody><tr><th> Nom du réactif </th><th> Société </th><th> Numéro de catalogue </th><th> Commentaires (optionnel) </th></tr><tr><td> Électrodes de stimulation </td><td> Teca </td><td> 25mmx26G </td><td> Stérile jetable électrodes aiguilles monopolaires </td></tr><tr><td> Stimulateur </td><td> L&#39;herbe </td><td> S88X </td><td></td></tr><tr><td> Unité d&#39;isolement de stimulation </td><td> L&#39;herbe </td><td> UES-C </td><td></td></tr><tr><td> Système de levier des muscles </td><td> Aurora scientifique </td><td> 310C-LR </td><td> Option de platine </td></tr><tr><td> Interface de signal </td><td> Aurora scientifique </td><td> Série 604A </td><td></td></tr><tr><td> Contrôle musculaire dynamique et logiciels d&#39;analyse </td><td> Aurora scientifique </td><td> Aurora scientifique </td><td></td></tr><tr><td> PC / Moniteur </td><td> Aurora scientifique </td><td> Ordinateur sous Windows XP </td><td></td></tr><tr><td> Dispositif de la position des membres </td><td> Aurora scientifique </td><td> NA </td><td> Peut être remplacé par cadre stéréotaxique </td></tr><tr><td> Tableau </td><td> Northstar douanes, LLC </td><td> NA </td><td> Personnalisé de table en </td></tr><tr><td> Envelopper flexible pour la fixation patte à pédales </td><td> Andover </td><td> PetFlex (5cmx2m) </td><td> Peut être réutilisé une fois ou deux </td></tr></tbody></table>

in vivo canine muscle function assay

Nous décrivons une méthode peu invasive et reproductible pour mesurer la force pelvienne canines musculaire des membres et de la réponse musculaire à répétition des contractions excentriques. Le membre pelvien d&#39;un chien anesthésié est immobilisé dans un cadre stéréotaxique pour aligner le tibia à angle droit sur le fémur. Adhésif envelopper appose sa patte à une pédale montée sur l&#39;arbre d&#39;un servomoteur pour mesurer le couple. Stimulation nerveuse percutanée active les muscles des membres postérieurs de la patte soit poussée (extension) ou tirer (flex) contre la pédale de générer un couple isométrique. La stimulation percutanée du nerf tibial active muscles extenseurs tibiotarsienne. Répétée excentrique (allongement) des contractions sont induites dans les muscles fléchisseurs tibiotarsienne par stimulation percutanée du nerf tibial. Le protocole se compose d&#39;un excentrique contraction initiale suivie d&#39;une isométrique étirer forcé imposé par le servomoteur. La rotation efficace allonge le muscle alors qu&#39;il contrats, par exemple, une contraction excentrique. Lors d&#39;une stimulation des muscles fléchisseurs sont soumis à une vue isométrique 800 ms et 200 ms contraction excentrique. Cette procédure est répétée toutes les 5 sec. Pour éviter la fatigue, 4 min de repos qui suit toutes les 10 contractions avec un total de 30 contractions effectuées.

Watch this Scientific Journal Video about In Vivo Canine Muscle Function Assay at JoVE.com

In Vivo Canine Muscle Function Assay

Nous décrivons une méthode peu invasive et indolore pour mesurer la force musculaire des membres postérieurs canine et de la réponse musculaire à répétition des contractions excentriques.

In Vivo Assay Muscle Fonction Canine

We describe a minimally-invasive and reproducible method to measure canine pelvic limb muscle strength and muscle response to repeated eccentric 
...

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Medicine

In Vivo Canine Muscle Function Assay

16.7K vues.  Wake Forest University. Nous décrivons une méthode peu invasive et indolore pour mesurer la force musculaire des membres postérieurs canine et de la réponse musculaire à répétition des contractions excentriques.

Vidéo: In Vivo Canine Muscle Function Assay

An in vivo Assay to Test Blood Vessel Permeability

This method is based on the intravenous injection of Evans Blue in mice as the test animal model. Evans blue is a dye that binds albumin. Under physiologic conditions the endothelium is impermeable to albumin, so Evans blue bound albumin remains restricted within blood vessels. In pathologic conditions that promote increased vascular permeability endothelial cells partially lose their close contacts and the endothelium becomes permeable to small proteins such as albumin. This condition allows for extravasation of Evans Blue in tissues. A healthy endothelium prevents extravasation of the dye in the neighboring vascularized tissues. Organs with increased permeability will show significantly increased blue coloration compared to organs with intact endothelium. The level of vascular permeability can be assessed by simple visualization or by quantitative measurement of the dye incorporated per milligram of tissue of control versus experimental animal/tissue. Two powerful aspects of this assay are its simplicity and quantitative characteristics. Evans Blue dye can be extracted from tissues by incubating a specific amount of tissue in formamide. Evans Blue absorbance maximum is at 620 nm and absorbance minimum is at 740 nm. By using a standard curve for Evans Blue, optical density measurements can be converted into milligram dye captured per milligram of tissue. Statistical analysis should be used to assess significant differences in vascular permeability.

An in vivo Assay to Test Blood Vessel Permeability

We are presenting an in vivo assay to test blood vessel permeability. This assay is based on intravenous injection of a dye and subsequent visualization of its diffusion into interstitial spaces.

Un<em&gt; In vivo</emTest&gt; Tester la perméabilité des vaisseaux sanguins

This method is based on the intravenous injection of Evans Blue in mice as the test animal model. Evans blue is a dye that binds albumin. Under ...

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Médecine

In vivo 19F MRI for Cell Tracking

In vivo 19F MRI allows quantitative cell tracking without the use of ionizing radiation. It is a noninvasive technique that can be applied to humans. Here, we describe a general protocol for cell labeling, imaging, and image processing. The technique is applicable to various cell types and animal models, although here we focus on a typical mouse model for tracking murine immune cells. The most important issues for cell labeling are described, as these are relevant to all models. Similarly, key imaging parameters are listed, although the details will vary depending on the MRI system and the individual setup. Finally, we include an image processing protocol for quantification. Variations for this, and other parts of the protocol, are assessed in the Discussion section. Based on the detailed procedure described here, the user will need to adapt the protocol for each specific cell type, cell label, animal model, and imaging setup. Note that the protocol can also be adapted for human use, as long as clinical restrictions are met.

In vivo 19F MRI for Cell Tracking

We describe a general protocol for in vivo cell tracking using MRI in a mouse model with ex vivo labeled cells. A typical protocol for cell labeling, image acquisition processing and quantification is included.

In vivo 19 F IRM pour le suivi cellulaire

In vivo 19F MRI allows quantitative cell tracking without the use of ionizing radiation. It is a noninvasive technique that can be applied to humans. ...

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 ...

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.

Évaluation de ventriculaire droite Structure et fonction dans le modèle de souris de l&#39;artère pulmonaire constriction par échocardiographie transthoracique

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

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 ...

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 ...

Depletion of Mouse Cells from Human Tumor Xenografts Significantly Improves Downstream Analysis of Target Cells

The use of in vitro cell line models for cancer research has been a useful tool. However, it has been shown that these models fail to reliably mimic patient tumors in different assays1. Human tumor xenografts represent the gold standard with respect to tumor biology, drug discovery, and metastasis research 2-4. Tumor xenografts can be derived from different types of material like tumor cell lines, tumor tissue from primary patient tumors4 or serially transplanted tumors. When propagated in vivo, xenografted tissue is infiltrated and vascularized by cells of mouse origin. Multiple factors such as the tumor entity, the origin of xenografted material, growth rate and region of transplantation influence the composition and the amount of mouse cells present in tumor xenografts. However, even when these factors are kept constant, the degree of mouse cell contamination is highly variable.
Contaminating mouse cells significantly impair downstream analyses of human tumor xenografts. As mouse fibroblasts show high plating efficacies and proliferation rates, they tend to overgrow cultures of human tumor cells, especially slowly proliferating subpopulations. Mouse cell derived DNA, mRNA, and protein components can bias downstream gene expression analysis, next-generation sequencing, as well as proteome analysis 5. To overcome these limitations, we have developed a fast and easy method to isolate untouched human tumor cells from xenografted tumor tissue. This procedure is based on the comprehensive depletion of cells of mouse origin by combining automated tissue dissociation with the benchtop tissue dissociator and magnetic cell sorting. Here, we demonstrate that human target cells can be can be obtained with purities higher than 96% within less than 20 min independent of the tumor type.

Human tumor xenografts are vascularized and infiltrated by cells of mouse origin during the growth phase in vivo. To circumvent the bias caused by these contaminating cells during downstream analysis, we developed a method allowing for comprehensive depletion of all mouse cells by magnetic cell sorting.

Appauvrissement des cellules de souris de xénogreffes de tumeurs humaines améliore de manière significative l&#39;analyse en aval des cellules cibles

The use of in vitro cell line models for cancer research has been a useful tool. However, it has been shown that these models fail to reliably mimic ...

Phosphorus-31 Magnetic Resonance Spectroscopy: A Tool for Measuring In Vivo Mitochondrial Oxidative Phosphorylation Capacity in Human Skeletal Muscle

Skeletal muscle mitochondrial oxidative phosphorylation (OXPHOS) capacity, which is critically important in health and disease, can be measured in vivo and noninvasively in humans via phosphorus-31 magnetic resonance spectroscopy (31PMRS). However, the approach has not been widely adopted in translational and clinical research, with variations in methodology and limited guidance from the literature. Increased optimization, standardization, and dissemination of methods for in vivo 31PMRS would facilitate the development of targeted therapies to improve OXPHOS capacity and could ultimately favorably impact cardiovascular health. 31PMRS produces a noninvasive, in vivo measure of OXPHOS capacity in human skeletal muscle, as opposed to alternative measures obtained from explanted and potentially altered mitochondria via muscle biopsy. It relies upon only modest additional instrumentation beyond what is already in place on magnetic resonance scanners available for clinical and translational research at most institutions. In this work, we outline a method to measure in vivo skeletal muscle OXPHOS. The technique is demonstrated using a 1.5 Tesla whole-body MR scanner equipped with the suitable hardware and software for 31PMRS, and we explain a simple and robust protocol for in-magnet resistive exercise to rapidly fatigue the quadriceps muscle. Reproducibility and feasibility are demonstrated in volunteers as well as subjects over a wide range of functional capacities.

Phosphorus-31 Magnetic Resonance Spectroscopy: A Tool for Measuring In Vivo Mitochondrial Oxidative Phosphorylation Capacity in Human Skeletal Muscle

This work demonstrates the feasibility of an in vivo phosphorus-31 magnetic resonance spectroscopy (31PMRS) technique to quantify mitochondrial oxidative phosphorylation (OXPHOS) capacity in human skeletal muscle.

Phosphore-31 Spectroscopie par résonance magnétique: un outil de mesure<em&gt; In Vivo</em&gt; Capacité mitochondrial phosphorylation oxydative dans le muscle squelettique humain

Skeletal muscle mitochondrial oxidative phosphorylation (OXPHOS) capacity, which is critically important in health and disease, can be measured in vivo ...

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.

Évaluation in vivo des propriétés mécaniques et viscoélastiques de la langue de rat

The tongue is a highly innervated and vascularized muscle hydrostat on the floor of the mouth of most vertebrates. Its primary functions include ...

Skeletal Muscle Neurovascular Coupling, Oxidative Capacity, and Microvascular Function with 'One Stop Shop' Near-infrared Spectroscopy

Exercise represents a major hemodynamic stress that demands a highly coordinated neurovascular response in order to match oxygen delivery to metabolic demand. Reactive hyperemia (in response to a brief period of tissue ischemia) is an independent predictor of cardiovascular events and provides important insight into vascular health and vasodilatory capacity. Skeletal muscle oxidative capacity is equally important in health and disease, as it determines the energy supply for myocellular processes. Here, we describe a simple, non-invasive approach using near-infrared spectroscopy to assess each of these major clinical endpoints (reactive hyperemia, neurovascular coupling, and muscle oxidative capacity) during a single clinic or laboratory visit. Unlike Doppler ultrasound, magnetic resonance images/spectroscopy, or invasive catheter-based flow measurements or muscle biopsies, our approach is less operator-dependent, low-cost, and completely non-invasive. Representative data from our lab taken together with summary data from previously published literature illustrate the utility of each of these end-points. Once this technique is mastered, application to clinical populations will provide important mechanistic insight into exercise intolerance and cardiovascular dysfunction.

Skeletal Muscle Neurovascular Coupling, Oxidative Capacity, and Microvascular Function with &#039;One Stop Shop&#039; Near-infrared Spectroscopy

Here, we describe a simple, non-invasive approach using near-infrared spectroscopy to assess reactive hyperemia, neurovascular coupling and skeletal muscle oxidative capacity in a single clinic or laboratory visit.

Couplage neurovasculaire Muscle squelettique, la capacité oxydative et microvasculaire fonction avec « One Stop Shop » de spectroscopie proche infrarouge

Exercise represents a major hemodynamic stress that demands a highly coordinated neurovascular response in order to match oxygen delivery to metabolic ...