Name: predicting amputation using local circulating mononuclear progenitor cells in angioplasty-treated patients with critical limb ischemia
Uploaded: 2020-09-22T13:00:00
Description: Watch this Scientific Journal Video about Predicting Amputation using Local Circulating Mononuclear Progenitor Cells in Angioplasty-treated Patients with Critical Limb Ischemia at JoVE.com

The authors thank the support of Institutional Program E015 for the project ID 356.2015.

The institutional research ethics committee from Centro M&#233;dico Nacional &#8220;20 de Noviembre&#8221; ISSSTE approved this prospective protocol, all enrolled patients provided written informed consent.
1. Evaluation of vascular block of lower limb, blood sampling and balloon angioplasty
NOTE: The study sample used for this experiment comprised of 20 diabetic patients, aged 68 years old and 10 out of 20 were males. Half of the sample were smokers and most prevalen...

<ol>
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J., Mart&#237;n-Conejero, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Peripheral+artery+disease:+Pathophysiology,+diagnosis+and+treatment.">Peripheral artery disease: Pathophysiology, diagnosis and treatment.</a> Revista Espa&#241;ola de Cardiolog&#237;a. 60 (9), 969-982 (2007).</li><li>Agarwal, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Burden+of+re-admissions+among+patients+with+critical+limb+ischemia.">Burden of re-admissions among patients with critical limb ischemia.</a> Journal of the American College of Cardiology. 69 (15), 1897-1908 (2017).</li><li>Kolte, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thirty-day+re-admissions+after+endovascular+or+surgical+therapy+for+critical+limb+ischemia:+Analysis+of+the+2013+to+2014+nationwide+re-admissions+databases.">Thirty-day re-admissions after endovascular or surgical therapy for critical limb ischemia: Analysis of the 2013 to 2014 nationwide re-admissions databases.</a> Circulation. 136 (2), 167-176 (2017).</li><li>Rowlands, T. E., Donnelly, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Medical+therapy+for+intermittent+claudication.">Medical therapy for intermittent claudication.</a> European Journal of Vascular and Endovascular Surgery. 34, 314-321 (2007).</li><li>Cronewett, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Acute limb ischemia and lower extremity chronic arterial disease: Rutherford's vascular surgery (8th ed.). , (2014).</li><li>Dick, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surgical+or+endovascular+revascularization+in+patients+with+critical+limb+ischemia:+influence+of+diabetes+mellitus+on+clinical+outcome.">Surgical or endovascular revascularization in patients with critical limb ischemia: influence of diabetes mellitus on clinical outcome.</a> Journal of Vascular Surgery. 45 (4), 751-761 (2007).</li><li>Su&#225;rez-Cuenca, J. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coronary+circulating+mononuclear+progenitor+cells+and+soluble+biomarkers+in+the+cardiovascular+prognosis+after+coronary+angioplasty.">Coronary circulating mononuclear progenitor cells and soluble biomarkers in the cardiovascular prognosis after coronary angioplasty.</a> Journal of Cellular and Molecular Medicine. 23 (7), 4844-4849 (2019).</li><li>Franz, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+autologous+bone+marrow+mononuclear+cell+implantation+therapy+as+a+limb+salvage+procedure+in+patients+with+severe+peripheral+arterial+disease.">Use of autologous bone marrow mononuclear cell implantation therapy as a limb salvage procedure in patients with severe peripheral arterial disease.</a> Journal of Vascular Surgery. 50 (6), 1378-1390 (2009).</li><li>Benoit, E., O'Donnell, T. F., Patel, A. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Safety+and+efficacy+of+autologous+cell+therapy+in+critical+limb+ischemia:+A+systematic+review.">Safety and efficacy of autologous cell therapy in critical limb ischemia: A systematic review.</a> Cellular Transplantation. 22 (3), 545-562 (2013).</li><li>Hill, J. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circulating+endothelial+progenitor+cells,+vascular+function,+and+cardiovascular+risk.">Circulating endothelial progenitor cells, vascular function, and cardiovascular risk.</a> New England Journal of Medicine. 348 (7), 593-600 (2003).</li><li>Schmidt-Lucke, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reduced+number+of+circulating+endothelial+progenitor+cells+predicts+future+cardiovascular+events:+proof+of+concept+for+the+clinical+importance+of+endogenous+vascular+repair.">Reduced number of circulating endothelial progenitor cells predicts future cardiovascular events: proof of concept for the clinical importance of endogenous vascular repair.</a> Circulation. 111 (22), 2981-2987 (2005).</li><li>Smadja, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Early+endothelial+progenitor+cells+in+bone+marrow+are+a+biomarker+of+cell+therapy+success+in+patients+with+critical+limb+ischemia.">Early endothelial progenitor cells in bone marrow are a biomarker of cell therapy success in patients with critical limb ischemia.</a> Cytotherapy. 14 (2), 232-239 (2012).</li><li>Kremastinos, D. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intracoronary+cyclic-GMP+and+cyclic-AMP+during+percutaneous+transluminal+coronary+angioplasty.">Intracoronary cyclic-GMP and cyclic-AMP during percutaneous transluminal coronary angioplasty.</a> International Journal of Cardiology. 53 (3), 227-232 (1996).</li><li>Truong, Q. A., Januzzi, J. L., Szymonifka, J., Thai, W. E., Wai, B., Lavender, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coronary+sinus+biomarker+sampling+compared+to+peripheral+venous+blood+for+predicting+outcomes+in+patients+with+severe+heart+failure+undergoing+cardiac+resynchronization+therapy:+the+BIOCRT+study.">Coronary sinus biomarker sampling compared to peripheral venous blood for predicting outcomes in patients with severe heart failure undergoing cardiac resynchronization therapy: the BIOCRT study.</a> Heart Rhythm. 11 (12), 2167-2175 (2014).</li><li>Ding, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fibrosis+and+inflammatory+markers+and+long-term+risk+of+peripheral+artery+disease:+The+ARIC+study.">Fibrosis and inflammatory markers and long-term risk of peripheral artery disease: The ARIC study.</a> Arteriosclerosis, Thrombosis and Vascular Biology. 40 (9), 2322-2331 (2020).</li><li>Potier, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Plasma+copeptin+and+risk+of+lower-extremity+amputation+in+Type+1+and+Type+2+diabetes.">Plasma copeptin and risk of lower-extremity amputation in Type 1 and Type 2 diabetes.</a> Diabetes Care. 40 (12), 2290-2297 (2019).</li><li>Schmidt-Lucke, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantification+of+circulating+endothelial+progenitor+cells+using+the+modified+ISHAGE+protocol.">Quantification of circulating endothelial progenitor cells using the modified ISHAGE protocol.</a> PLoS One. 5 (1), 13790 (2010).</li><li>Marboeuf, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inflammation+triggers+colony+forming+endothelial+cell+mobilization+after+angioplasty+in+chronic+lower+limb+ischemia.">Inflammation triggers colony forming endothelial cell mobilization after angioplasty in chronic lower limb ischemia.</a> Journal of Thrombosis and Haemostasis. 6 (1), 195-197 (2008).</li><li>Regueiro, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mobilization+of+endothelial+progenitor+cells+in+acute+cardiovascular+events+in+the+PROCELL+study:+Time-course+after+acute+myocardial+infarction+and+stroke.">Mobilization of endothelial progenitor cells in acute cardiovascular events in the PROCELL study: Time-course after acute myocardial infarction and stroke.</a> Journal of Molecular and Cellular Cardiology. 80, 146-155 (2015).</li></ol>

Blood collection at the precise site of the vascular block may show technical difficulties; therefore, we performed blood collection in the proximity to vascular block. Likewise, the amount of MPCs close to the vascular plaque seems to be highly dynamic and may originate variations before and after angioplasty. According to our observations, it is recommended to evaluate baseline- and 30min-post-angioplasty changes in the number of MPCs, since they may reflect several pathophysiological processes occurring within vascula...

Peripheral Arterial Disease (PAD) is characterized by a chronic and progressive vascular obstruction with limitation of blood supply1. At a global scale, PAD of the lower limbs affects around 10% of the elderly population, while up to 7% of such cases are submitted to limb amputation2,3.
Critical Limb Ischemia (CLI) represents the most serious presentation of PAD1. Patients usually experience pain at rest, ulcers, or gangrene attributable to occluded arteries; while clinical prognosis is unfavorable and marked by a 30% risk of limb amputation and mortality during 1 year3,4,5.
Angioplasty is a minimally invasive endovascular procedure that can restore blood flow to the lower limb in patients with CLI; however, some patients will inevitably require major limb amputation, even after angioplasty therapy1,5. Early identification of unfavorable outcomes after angioplasty is quite valuable, due to the possibility of therapy enforcement.
Traditional risk factors may provide a limited predictive ability for major limb amputation in patients with CLI undergoing angioplasty6. Pathophysiology-oriented biomarkers represent novel methods with potential clinical applications, which may result specifically useful in diseases related to vascular injury7. Nowadays, the participation of cellular populations owning endothelial repair properties, at the site of the atherosclerotic plaque, has been increasingly recognized8,9.
Mononuclear Progenitor Cells (MPCs) are derived from the bone marrow and own structural and functional characteristics of stem cells with vascular regenerative abilities. Due to MPC&#8217;s ability to proliferate, migrate and show vascular adherence; these cells have become good candidates to reflect endothelial repair in response to ischemia10,11,12. In addition, continuous interest in mechanisms underlying vascular injury has motivated exploring the prognostic role of local occurring biomarkers, since they are considered to reflect vascular damage and repair7,13,14.
The purpose of the present study is to describe how to determine the amount of MPCs that circulate close to the vascular obstruction in patients with CLI undergoing angioplasty; and how to evaluate the relation between MPCs with indicators of endothelial dysfunction and limb amputation.
Compared to the prognosis based on comorbidities and intrinsic vascular features, the amount of local MPCs show specific ability to predict clinical outcome regarding endothelial dysfunction and limb amputation. Consistently, some studies have described the prognostic role of similar biomarkers during the evaluation of patients with PAD15,16.
Based on previous results7, the method described here may be useful for an early identification of population at risk of adverse vascular outcomes in several clinical settings, such as lower limb and coronary ischemia, stroke, vasculitis, venous thrombosis and others involving vascular injury and repair.

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			<td>Bovine Serum Albumin (BSA) as a buffering agent, stabilizer, standard and for blending.</td>
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			<td>Miltenyi Biotec / MACS</td>
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			<td>Miltenyi Biotec / MACS</td>
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			<td>The monoclonal antibody clone AC136 detecs a class III epitope of the CD34</td>
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			<td>Miltenyi Biotec / MACS</td>
			<td>#130-092-880</td>
			<td>Monoclonal CD45 Antibody, human conjugated</td>
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			<td>Thermo SCIENTIFIC</td>
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			<td>5 mL Polystyrene Round-Bottom Tube. 12x75 style. Sterile.</td>
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			<td>Hemocytometer for cell counting. (range 0.1000mm, 0.0025mm2)</td>
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			<td>K2 EDTA Blood Collection Tubes</td>
			<td>BD Vacutainer</td>
			<td>#367863</td>
			<td>Lilac plastic vacutainer tube (K2E) 10.8mg, 6 mL.</td>
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			<td>Lymphoprep</td>
			<td>Stemcell Technologies</td>
			<td>01-63-12-002-A</td>
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			<td>The transfer pipette is a tool that facilitates liquid transfer with greater accuracy.</td>
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			<td>KIMBLE CHASE</td>
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predicting amputation using local circulating mononuclear progenitor cells in angioplasty-treated patients with critical limb ischemia

Critical limb ischemia (CLI) represents an advanced stage of the peripheral arterial disease. Angioplasty improves the blood flow to the lower limb; however, some patients irreversibly progress to limb amputation. The extent of vascular damage and the mechanisms of vascular repair are factors affecting post-angioplasty outcome. Mononuclear Progenitor Cells (MPCs) are reactive to vascular damage and repair, with the ability to reflect vascular diseases. The present protocol describes quantification of MPCs obtained from blood circulation from vessel close to the angioplasty site, as well as its relationship with endothelial dysfunction and its predictive ability for limb amputation in the next 30 days after angioplasty in patients with CLI.

Blood samples from blocked arteries, at the site addressed for angioplasty, were collected from 20 diabetic patients, aged 68 years old and 10 out of 20 were males. Half of sample population were smokers. Vascular lesions were mainly scored as Rutherford class VI; whereas patients showed a higher prevalence of type 2 Diabetes Mellitus (100%), hypertension (70%) and dyslipidemia (55%).
A 30 days clinical follow up after lower limb angioplasty was carried out. The percentage of MPC subpopulation...

Watch this Scientific Journal Video about Predicting Amputation using Local Circulating Mononuclear Progenitor Cells in Angioplasty-treated Patients with Critical Limb Ischemia at JoVE.com

Predicting Amputation using Local Circulating Mononuclear Progenitor Cells in Angioplasty-treated Patients with Critical Limb Ischemia

Lower limb amputation may occur even after angioplasty of obstructed vessels in Critical Limb Ischemia (CLI). Mononuclear Progenitor Cells (MPCs) reflect vascular repair. The present protocol describes the quantification of MPCs from circulation close to angioplasty, and its relationship with endothelial dysfunction and prediction of lower limb amputation.

Critical limb ischemia (CLI) represents an advanced stage of the peripheral arterial disease. Angioplasty improves the blood flow to the lower limb; ...

Although angioplasty improves blood flow in critical limb ischemia, some patients will still progress to limb amputation. Compared to prognosis based on traditional risk factors and intrinsic vascular features, the number of local MPCs can be more predictive of the clinical outcome, regarding endothelial dysfunction and limb amputation. The number of local MPCs represents a promising indicator of the prognosis of vascular events, such as ischemia heart disease, and lower limb ischemia, with potential application in risk stratification and prevention enforcement.Demonstrating the procedures will be Eduardo Vera-Gomez, Alejandro Hernandez-Patricio, Carolina Aranda-Rodriguez, Juan Ariel Gutierrez-Buendia, Atzin Sua Ruiz-Hernandez, Mario Antonio Tellez-Gonzalez, and Gabrielle Alexandra Dominguez-Perez. PhD's from the laboratories of experimental metabolism and tissue regeneration, as well, will be Gabrielle Hernandez-De Rubin and Oscar Antonio Loman-Zuniga. And these from the vascular surgery department.To determine the pre and post angioplasty FMD, use a vascular linear transducer to measure the diameter of the brachial artery of the patient. Next place, the cuff of a sphygmomanometer above the measurement site in the forearm, and insufflate the cuff 50 millimeters of mercury above the systolic blood pressure for five minutes before deflating. Within 60 seconds of deflating, measure the brachial artery diameter again, and use the equation to estimate the FMD.To evaluate the clinical severity of limb ischemia, according to the Rutherford classification, place an 18 gauge needle into the blood vessel at the selected groin site, and place an introducer over the needle. Advance a flexible guidewire into the introducer and replace the guide with a six French introducer. Using fluoroscopic guidance, inject contrast medium to identify the artery trajectory and blocked vascular sites.Introduce two, 0.014 French navigation guidewires and two, 0.014 French support guidewires into the vessel, and advance the guide wires to the blocked site. Next, introduce one five French catheter, and then one three French catheter, and collect 10 milliliters of blood from the site closest to the vascular obstruction. Place the sample on ice and advance a guidewire again.When the guidewire is in place, introduce an angioplasty balloon catheter, containing an inflatable balloon located at the end of the catheter, and advance the angioplasty balloon catheter to the site of the lesion. Inflate the balloon against the blocking plaque, located at the vascular wall, and verify restoration of the blood flow. 30 minutes after performing the angioplasty, advance a catheter to the site closest to the vascular block and collect 10 milliliters of blood.Then, remove all of the guidewires and provide the appropriate post-operative care. Two weeks after the angioplasty, evaluate the clinical severity of the limb ischemia, the resolving rest pain, lower ischemia, and functional foot preservation, according to the Rutherford classification, and identify those cases requiring a major amputation due to an unfavorable outcome. Within one hour of collection, transfer six milliliters of each collected blood sample into new 15 milliliter tubes, and dilute the samples at a one-to-one ratio in PBS.Add two milliliters of density gradient medium to each of three test tubes, and add three equal volume aliquots of the diluted blood to each tube to no more than three quarters full. Separate the blood cells by density gradient centrifugation, and use a pipette to collect the cells of the interface of the resulting layers. Pull the cells from each sample into a single 15 milliliter tube, and wash each sample six times, with two milliliters of PBS per wash.After the last wash, re-suspend the MPC containing pellets in one milliliter of PBS per sample for counting, and add one times 10 to the six cells per tube to the appropriate number of five milliliter flow cytometry tubes per sample. Pellet the cells by centrifugation, and re-suspend each cell sample in 100 microliters of the antibody cocktail of interest for 10 seconds, before incubating the cells for 20 minutes at four degrees Celsius, protected from light. At the end of the incubation, use isotype-matched control antibodies to set up the appropriate forward and side scatter gates for analysis, and use a tube containing a high number of CD45 and CD34 positive cells to gate the NPCs.To select for double positive immuno phenotypes, create new plots and gate-identify the KDR, CD133 and CD184 positive, CD34 positive, CD45 positive cells, then gate to identify the main MPC subpopulations. The number of MPCs can then be correlated with the baseline FMD value, and post angioplasty delta of FMD, and the proportion of patients requiring major amputation of the lower limb. In this representative analysis, 30 days after lower limb angioplasty, the baseline number of CD45 positive, CD34 positive, KDR positive MPCs, negatively correlated with the FMD.Whereas the change in CD45 positive, CD34 positive, CD133 positive, CD184 positive MPCs, after angioplasty, significantly correlated with FMD improvement. An increased baseline number of MPCs CD45 positive, CD34 positive, KDR positive subpopulations, as well as post angioplasty reduction in the MPC CD45 positive, CD34 positive, CD133 positive, CD184 positive cells, were also observed in patients, who evolved to limb amputation, During the vascular approach, be sure to collect the blood from the site closest to the vascular obstruction.

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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.

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

A Research Method For Detecting Transient Myocardial Ischemia In Patients With Suspected Acute Coronary Syndrome Using Continuous ST-segment Analysis

Each year, an estimated 785,000 Americans will have a new coronary attack, or acute coronary syndrome (ACS). The pathophysiology of ACS involves rupture of an atherosclerotic plaque; hence, treatment is aimed at plaque stabilization in order to prevent cellular death. However, there is considerable debate among clinicians, about which treatment pathway is best: early invasive using percutaneous coronary intervention (PCI/stent) when indicated or a conservative approach (i.e., medication only with PCI/stent if recurrent symptoms occur).
There are three types of ACS: ST elevation myocardial infarction (STEMI), non-ST elevation MI (NSTEMI), and unstable angina (UA). Among the three types, NSTEMI/UA is nearly four times as common as STEMI. Treatment decisions for NSTEMI/UA are based largely on symptoms and resting or exercise electrocardiograms (ECG). However, because of the dynamic and unpredictable nature of the atherosclerotic plaque, these methods often under detect myocardial ischemia because symptoms are unreliable, and/or continuous ECG monitoring was not utilized.
Continuous 12-lead ECG monitoring, which is both inexpensive and non-invasive, can identify transient episodes of myocardial ischemia, a precursor to MI, even when asymptomatic. However, continuous 12-lead ECG monitoring is not usual hospital practice; rather, only two leads are typically monitored. Information obtained with 12-lead ECG monitoring might provide useful information for deciding the best ACS treatment.
Purpose. Therefore, using 12-lead ECG monitoring, the COMPARE Study (electroCardiographic evaluatiOn of ischeMia comParing invAsive to phaRmacological trEatment) was designed to assess the frequency and clinical consequences of transient myocardial ischemia, in patients with NSTEMI/UA treated with either early invasive PCI/stent or those managed conservatively (medications or PCI/stent following recurrent symptoms). The purpose of this manuscript is to describe the methodology used in the COMPARE Study.
Method. Permission to proceed with this study was obtained from the Institutional Review Board of the hospital and the university. Research nurses identify hospitalized patients from the emergency department and telemetry unit with suspected ACS. Once consented, a 12-lead ECG Holter monitor is applied, and remains in place during the patient's entire hospital stay. Patients are also maintained on the routine bedside ECG monitoring system per hospital protocol. Off-line ECG analysis is done using sophisticated software and careful human oversight.

Continuous 12-lead electrocardiographic (ECG) monitoring can identify transient myocardial ischemia, even when asymptomatic, among patients with suspected acute coronary syndrome (ACS). In this article we describe our method for initiating patient monitoring using a Holter device, downloading the ECG data for off-line analysis, and how to utilize the ECG software to identify transient ischemia.

Each year, an estimated 785,000 Americans will have a new coronary attack, or acute coronary syndrome (ACS). The pathophysiology of ACS involves rupture ...

In vitro Method to Observe E-selectin-mediated Interactions Between Prostate Circulating Tumor Cells Derived From Patients and Human Endothelial Cells

Metastasis is a process in which tumor cells shed from the primary tumor intravasate blood vascular and lymphatic system, thereby, gaining access to extravasate and form a secondary niche.&#160;The extravasation of tumor cells from the blood vascular system can be studied using endothelial cells (ECs) and tumor cells obtained from different cell lines.&#160;Initial studies were conducted using static conditions but it has been well documented that ECs behave differently under physiological flow conditions.&#160;Therefore, different flow chamber assemblies are currently being used to studying cancer cell interactions with ECs.&#160;Current flow chamber assemblies offer reproducible results using either different cell lines or fluid at different shear stress conditions.&#160;However, to observe and study interactions with rare cells such as circulating tumor cells (CTCs), certain changes are required to be made to the conventional flow chamber assembly.&#160;CTCs are a rare cell population among millions of blood cells. Consequently, it is difficult to obtain a pure population of CTCs.&#160;Contamination of CTCs with different types of cells normally found in the circulation is inevitable using present enrichment or depletion techniques.&#160;In the present report, we describe a unique method to fluorescently label circulating prostate cancer cells and study their interactions with ECs in a self-assembled flow chamber system.&#160;This technique can be further applied to observe interactions between prostate CTCs and any protein of interest.

In vitro Method to Observe E-selectin-mediated Interactions Between Prostate Circulating Tumor Cells Derived From Patients and Human Endothelial Cells

Our report describes a unique method to visualize and analyze CTC/EC interactions in prostate cancer under physiological flow conditions.

Metastasis is a process in which tumor cells shed from the primary tumor intravasate blood vascular and lymphatic system, thereby, gaining access to ...

Studying Pancreatic Cancer Stem Cell Characteristics for Developing New Treatment Strategies

Pancreatic ductal adenocarcinoma (PDAC) contains a subset of exclusively tumorigenic cancer stem cells (CSCs) which have been shown to drive tumor initiation, metastasis and resistance to radio- and chemotherapy. Here we describe a specific methodology for culturing primary human pancreatic CSCs as tumor spheres in anchorage-independent conditions. Cells are grown in serum-free, non-adherent conditions in order to enrich for CSCs while their more differentiated progenies do not survive and proliferate during the initial phase following seeding of single cells. This assay can be used to estimate the percentage of CSCs present in a population of tumor cells. Both size (which can range from 35 to 250 micrometers) and number of tumor spheres formed represents CSC activity harbored in either bulk populations of cultured cancer cells or freshly harvested and digested tumors 1,2. Using this assay, we recently found that metformin selectively ablates pancreatic CSCs; a finding that was subsequently further corroborated by demonstrating diminished expression of pluripotency-associated genes/surface markers and reduced in vivo tumorigenicity of metformin-treated cells. As the final step for preclinical development we treated mice bearing established tumors with metformin and found significantly prolonged survival. Clinical studies testing the use of metformin in patients with PDAC are currently underway (e.g., NCT01210911, NCT01167738, and NCT01488552). Mechanistically, we found that metformin induces a fatal energy crisis in CSCs by enhancing reactive oxygen species (ROS) production and reducing mitochondrial transmembrane potential. In contrast, non-CSCs were not eliminated by metformin treatment, but rather underwent reversible cell cycle arrest. Therefore, our study serves as a successful example for the potential of in vitro sphere formation as a screening tool to identify compounds that potentially target CSCs, but this technique will require further in vitro and in vivo validation to eliminate false discoveries.

Pancreatic cancer stem cells (CSCs) can be expanded in vitro using the anchorage-independent sphere culture technique, which represents a powerful tool to study CSC biology and can serve as the first step to develop novel CSC-targeting therapies. Here the methodology for expanding, analyzing and targeting of pancreatic CSCs is provided.

Pancreatic ductal adenocarcinoma (PDAC) contains a subset of exclusively tumorigenic cancer stem cells (CSCs) which have been shown to drive tumor ...

Modeling Encephalopathy of Prematurity Using Prenatal Hypoxia-ischemia with Intra-amniotic Lipopolysaccharide in Rats

Encephalopathy of prematurity (EoP) is a term that encompasses the central nervous system (CNS) abnormalities associated with preterm birth. To best advance translational objectives and uncover new therapeutic strategies for brain injury associated with preterm birth, preclinical models of EoP must include similar mechanisms of prenatal global injury observed in humans and involve multiple components of the maternal-placental-fetal system. Ideally, models should produce a similar spectrum of functional deficits in the mature animal and recapitulate multiple aspects of the pathophysiology. To mimic human systemic placental perfusion defects, placental underperfusion and/or chorioamnionitis associated with pathogen-induced inflammation in early preterm birth, we developed a model of prenatal transient systemic hypoxia-ischemia (TSHI) combined with intra-amniotic lipopolysaccharide (LPS). In pregnant Sprague Dawley rats, TSHI via uterine artery occlusion on embryonic day 18 (E18) induces a graded placental underperfusion defect associated with increasing CNS damage in the fetus. When combined with intra-amniotic LPS injections, placental inflammation is increased and CNS damage is compounded with associated white matter, gait and imaging abnormalities. Prenatal TSHI and TSHI+LPS prenatal insults meet several of the criteria of an EoP model including recapitulating the intrauterine insult, causing loss of neurons, oligodendrocytes and axons, loss of subplate, and functional deficits in adult animals that mimic those observed in children born extremely preterm. Moreover, this model allows for the dissection of inflammation induced by divergent injury types.

Encephalopathy of prematurity encompasses the central nervous system abnormalities associated with injury from preterm birth. This report describes a clinically relevant rat model of in utero transient systemic hypoxia-ischemia and intra-amniotic lipopolysaccharide administration (LPS) that mimics chorioamnionitis, and the related impact of infectious stimuli and placental underperfusion on CNS development.

Encephalopathy of prematurity (EoP) is a term that encompasses the central nervous system (CNS) abnormalities associated with preterm birth. To best ...

A Method for Quantifying Upper Limb Performance in Daily Life Using Accelerometers

A key reason for referral to rehabilitation services after stroke and other neurological conditions is to improve one's ability to function in daily life. It has become important to measure a person's activities in daily life, and not just measure their capacity for activity in the structured environment of a clinic or laboratory. A wearable sensor that is now enabling measurement of daily movement is the accelerometer. Accelerometers are commercially-available devices resembling large wrist watches that can be worn throughout the day. Data from accelerometers can quantify how the limbs are engaged to perform activities in peoples' homes and communities. This report describes a methodology to collect accelerometry data and turn it into clinically-relevant information. First, data are collected by having the participant wear two accelerometers (one on each wrist) for 24 h or longer. The accelerometry data are then downloaded and processed to produce four different variables that describe key aspects of upper limb activity in daily life: hours of use, use ratio, magnitude ratio, and the bilateral magnitude. Density plots can be constructed that visually represent the data from the 24 h wearing period. The variables and their resultant density plots are highly consistent in neurologically-intact, community-dwelling adults. This striking consistency makes them a useful tool for determining if upper limb daily performance is different from normal. This methodology is appropriate for research studies investigating upper limb dysfunction and interventions designed to improve upper limb performance in daily life in people with stroke and other patient populations. Because of its relative simplicity, it may not be long before it is also incorporated in clinical neurorehabilitation practice.

This protocol describes a method to quantify upper limb performance in daily life using wrist-worn accelerometers.

A key reason for referral to rehabilitation services after stroke and other neurological conditions is to improve one's ability to function in daily life. ...

A Detailed Protocol for Physiological Parameters Acquisition and Analysis in Neurosurgical Critical Patients

Intracranial pressure (ICP) monitoring is now widely used in neurosurgical critical patients. Besides mean ICP value, the ICP derived parameters such as ICP waveform, amplitude of pulse (AMP), the correlation of ICP amplitude and ICP mean (RAP), pressure reactivity index (PRx), ICP and arterial blood pressure (ABP) wave amplitude correlation (IAAC), and so on, can reflect intracranial status, predict prognosis, and can also be used as guidance of proper treatment. However, most of the clinicians focus only on the mean ICP value while ignoring these parameters because of the limitations of the current devices. We have recently developed a multimodality monitoring system to address these drawbacks. This portable, user-friendly system will use a data collecting and storing device to continuously acquire patients&#39; physiological parameters first, i.e., ABP, ICP, and oxygen saturation, and then analyze these physiological parameters. We hope that the multimodality monitoring system will be accepted as a key measure to monitor physiological parameters, to analyze the current clinical status, and to predict the prognosis of the neurosurgical critical patients.

Recently, we have developed a portable multimodality monitoring system for the monitoring of various physiological parameters in neurosurgical critical patients. Detailed protocols on how to use this multimodality monitoring system are presented here.

Intracranial pressure (ICP) monitoring is now widely used in neurosurgical critical patients. Besides mean ICP value, the ICP derived parameters such as ...

Objective Nociceptive Assessment in Ventilated ICU Patients: A Feasibility Study Using Pupillometry and the Nociceptive Flexion Reflex

The concept of objective nociceptive assessment and optimal pain management have gained increasing attention. Despite the known negative short- and long-term consequences of unresolved pain or excessive analgosedation, adequate nociceptive monitoring remains challenging in non-communicative, critically ill adults. In the intensive care unit (ICU), routine nociceptive evaluation is carried out by the attending nurse using the Behavior Pain Scale (BPS) in mechanically ventilated patients. This assessment is limited by medication use (e.g., neuromuscular blocking agents) and the inherent subjective character of nociceptive evaluation by third parties.
Here, we describe the use of two nociceptive reflex testing devices as tools for objective pain evaluation: the pupillary dilation reflex (PDR) and nociception flexion reflex (NFR). These measurement tools are non-invasive and well tolerated, providing clinicians and researchers with objective information regarding two different nociceptive processing pathways: (1)&#160;the pain-related autonomic reactivity&#160;and (2) the ascending component of the somatosensory system. The use of PDR and NFR measurements are currently limited to specialized pain clinics and research institutions because of impressions that these are technically demanding or time-consuming procedures, or even because of a lack of knowledge regarding their existence.
By focusing on the two abovementioned nociceptive reflex assessments, this study evaluated their feasibility as a physiological pain measurement method in daily practice. Pursuing novel technologies for evaluating the analgesia level in unconscious patients may further improve individual pharmacological treatment and patient related outcome measures. Therefore, future research must include large well-designed clinical trials in a real-life environment.

Pain assessment in anesthetized patients who cannot communicate with the outside world in any way remains challenging despite the development of innovative objective pain evaluation tools. In this project, the pupillary dilation reflex and the nociception flexion reflex are assessed in critically ill, mechanically ventilated adult patients.

The concept of objective nociceptive assessment and optimal pain management have gained increasing attention. Despite the known negative short- and ...

Endotoxin Activity Assay for the Detection of Whole Blood Endotoxemia in Critically Ill Patients

Lipopolysaccharide, also known as endotoxin, is a fundamental component of gram-negative bacteria and plays a crucial role in the development of sepsis and septic shock. The early identification of an infectious process that is rapidly evolving to a critical illness might prompt a quicker and more intensive treatment, thereby potentially leading to better patient outcomes. The Endotoxin Activity (EA) assay can be used at the bedside as a reliable biomarker of systemic endotoxemia. The detection of elevated endotoxin activity levels has been repeatedly shown to be associated with an increased disease severity in patients with sepsis and septic shock. The assay is quick and easy to perform. Briefly, after sampling, an aliquot of whole blood is mixed with an anti-endotoxin antibody and with added LPS. Endotoxin activity is measured as the relative oxidative burst of primed neutrophils as detected by chemioluminescence. The assay&#39;s output is expressed on a scale from 0 (absent) to 1 (maximal) and categorized as &#8220;low&#8221; (&#60;0.4 units), &#8220;intermediate&#8221; (0.4&#8211;0.59 units), or &#8220;high&#8221; (&#8805;0.6 units). The detailed methodology and rationale for the implementation of the EA assay are reported in this manuscript.

We hereby present a protocol to measure at the bedside the endotoxin activity of human whole blood samples. The Endotoxin Activity assay is a simple test to perform and may be a useful biomarker in critically ill patients with sepsis.

Lipopolysaccharide, also known as endotoxin, is a fundamental component of gram-negative bacteria and plays a crucial role in the development of sepsis ...

Preclinical Model of Hind Limb Ischemia in Diabetic Rabbits

Peripheral vascular disease is a widespread clinical problem that affects millions of patients worldwide. A major consequence of peripheral vascular disease is the development of ischemia. In severe cases, patients can develop critical limb ischemia in which they experience constant pain and an increased risk of limb amputation. Current therapies for peripheral ischemia include bypass surgery or percutaneous interventions such as angioplasty with stenting or atherectomy to restore blood flow. However, these treatments often fail to the continued progression of vascular disease or restenosis or are contraindicated due to the overall poor health of the patient. A promising potential approach to treat peripheral ischemia involves the induction of therapeutic neovascularization to allow the patient to develop collateral vasculature. This newly formed network alleviates peripheral ischemia by restoring perfusion to the affected area. The most frequently employed preclinical model for peripheral ischemia utilizes the creation of hind limb ischemia in healthy rabbits through femoral artery ligation. In the past, however, there has been a strong disconnect between the success of preclinical studies and the failure of clinical trials regarding treatments for peripheral ischemia. Healthy animals typically have robust vascular regeneration in response to surgically induced ischemia, in contrast to the reduced vascularity and regeneration in patients with chronic peripheral ischemia. Here, we describe an optimized animal model for peripheral ischemia in rabbits that includes hyperlipidemia and diabetes. This model has reduced collateral formation and blood pressure recovery in comparison to a model with a higher cholesterol diet. Thus, the model may provide better correlation with human patients with compromised angiogenesis from the common co-morbidities that accompany peripheral vascular disease.

We describe a surgical procedure used to induce peripheral ischemia in rabbits with hyperlipidemia and diabetes. This surgery acts as a preclinical model for conditions experienced in peripheral artery disease in patients. Angiography is also described as a means to measure the extent of introduced ischemia and recovery of perfusion.

Peripheral vascular disease is a widespread clinical problem that affects millions of patients worldwide. A major consequence of peripheral vascular ...