JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
A valid and reliable assessment tool for remote simulation-based ultrasound-guided regional anesthesia.
Reg Anesth Pain Med
PUBLISHED: 10-12-2014
Show Abstract
Hide Abstract
The purpose of this study was to establish construct and concurrent validity and interrater reliability of an assessment tool for ultrasound-guided regional anesthesia (UGRA) performance on a high-fidelity simulation model.
Related JoVE Video
Photopatterning of Hydrogel Scaffolds Coupled to Filter Materials Using Stereolithography for Perfused 3D Culture of Hepatocytes.
Biotechnol. Bioeng.
PUBLISHED: 09-10-2014
Show Abstract
Hide Abstract
In vitro models that recapitulate the liver's structural and functional complexity could prolong hepatocellular viability and function to improve platforms for drug toxicity studies and understanding liver pathophysiology. Here, stereolithography (SLA) was employed to fabricate hydrogel scaffolds with open channels designed for post-seeding and perfused culture of primary hepatocytes that form 3D structures in a bioreactor. Photopolymerizable polyethylene glycol-based hydrogels were fabricated coupled to chemically activated, commercially available filters (polycarbonate and polyvinylidene fluoride) using a chemistry that permitted cell viability, and was robust enough to withstand perfused culture of up to 1 ?L/sec for at least 7 days. SLA energy dose, photoinitiator concentrations, and pretreatment conditions were screened to determine conditions that maximized cell viability and hydrogel bonding to the filter. Multiple open channel geometries were readily achieved, and included ellipses and rectangles. Rectangular open channels employed for subsequent studies had final dimensions on the order of 350 ?m by 850 ?m. Cell seeding densities and flow rates that promoted cell viability were determined. Perfused culture of primary hepatocytes in hydrogel scaffolds in the presence of soluble epidermal growth factor (EGF) prolonged the maintenance of albumin production throughout the 7-day culture relative to 2D controls. This technique of bonding hydrogel scaffolds can be employed to fabricate soft scaffolds for a number of bioreactor configurations and applications. Biotechnol. Bioeng. © 2014 Wiley Periodicals, Inc.
Related JoVE Video
Understanding patients' perspective of statin therapy: can we design a better approach to the management of dyslipidaemia? A literature review.
Singapore Med J
PUBLISHED: 09-06-2014
Show Abstract
Hide Abstract
Dyslipidaemia leads to atherosclerosis and is a major risk factor for cardiovascular diseases. In clinical trials, 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors, or statins, have been shown to effectively reduce dyslipidaemia. Despite the availability and accessibility of statins, myocardial infarctions and cerebrovascular accidents remain among the top causes of mortality in developed countries, including Singapore. This enigma could be attributed to suboptimal adherence to statin therapy. The present literature review aimed to evaluate patients' perceptions of statin therapy.
Related JoVE Video
Three-dimensionally printed biological machines powered by skeletal muscle.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 06-30-2014
Show Abstract
Hide Abstract
Combining biological components, such as cells and tissues, with soft robotics can enable the fabrication of biological machines with the ability to sense, process signals, and produce force. An intuitive demonstration of a biological machine is one that can produce motion in response to controllable external signaling. Whereas cardiac cell-driven biological actuators have been demonstrated, the requirements of these machines to respond to stimuli and exhibit controlled movement merit the use of skeletal muscle, the primary generator of actuation in animals, as a contractile power source. Here, we report the development of 3D printed hydrogel "bio-bots" with an asymmetric physical design and powered by the actuation of an engineered mammalian skeletal muscle strip to result in net locomotion of the bio-bot. Geometric design and material properties of the hydrogel bio-bots were optimized using stereolithographic 3D printing, and the effect of collagen I and fibrin extracellular matrix proteins and insulin-like growth factor 1 on the force production of engineered skeletal muscle was characterized. Electrical stimulation triggered contraction of cells in the muscle strip and net locomotion of the bio-bot with a maximum velocity of ? 156 ?m s(-1), which is over 1.5 body lengths per min. Modeling and simulation were used to understand both the effect of different design parameters on the bio-bot and the mechanism of motion. This demonstration advances the goal of realizing forward-engineered integrated cellular machines and systems, which can have a myriad array of applications in drug screening, programmable tissue engineering, drug delivery, and biomimetic machine design.
Related JoVE Video
Finite element analysis to model complex mitral valve repair.
Asian Cardiovasc Thorac Ann
PUBLISHED: 06-07-2014
Show Abstract
Hide Abstract
Although finite element analysis has been used to model simple mitral repair, it has not been used to model complex repair. A virtual mitral valve model was successful in simulating normal and abnormal valve function. Models were then developed to simulate an edge-to-edge repair and repair employing quadrangular resection. Stress contour plots demonstrated increased stresses along the mitral annulus, corresponding to the annuloplasty. The role of finite element analysis in guiding clinical practice remains undetermined.
Related JoVE Video
Mitral valve repair in acquired dextrocardia.
Asian Cardiovasc Thorac Ann
PUBLISHED: 05-16-2014
Show Abstract
Hide Abstract
Surgical correction of valvular heart disease in patients with dextrocardia is extremely rare. We report a surgical case of mitral valve repair in a patient with acquired dextrocardia. Successful mitral valve repair was performed through a right lateral thoracotomy. We describe our surgical strategy and summarize the literature.
Related JoVE Video
Refining the ultrasound-guided interscalene brachial plexus block: the superior trunk approach.
Can J Anaesth
PUBLISHED: 05-14-2014
Show Abstract
Hide Abstract
The conventional ultrasound-guided interscalene block targets the C5 and C6 nerve roots at approximately the level of the cricoid cartilage where they lie in the groove between the anterior and middle scalene muscles. This technique, although effective at providing regional anesthesia of the shoulder, is associated with risks of phrenic nerve palsy, injury to the dorsal scapular and long thoracic nerves, and long-term postoperative neurologic symptoms. In this case report, we describe the ultrasound-guided superior trunk block. This procedure targets the C5 and C6 components of the brachial plexus more distally after they unite into the superior trunk but before the suprascapular nerve branches off.
Related JoVE Video
Collective cell traction force analysis on aligned smooth muscle cell sheet between three-dimensional microwalls.
Interface Focus
PUBLISHED: 04-22-2014
Show Abstract
Hide Abstract
During the past two decades, novel biomaterial scaffold for cell attachment and culture has been developed for applications in tissue engineering, biosensing and regeneration medicine. Tissue engineering of blood vessels remains a challenge owing to the complex three-layer histology involved. In order to engineer functional blood vessels, it is essential to recapitulate the characteristics of vascular smooth muscle cells (SMCs) inside the tunica media, which is known to be critical for vasoconstriction and vasodilation of the circulatory system. Until now, there has been a lack of understanding on the mechanotransduction of the SMC layer during the transformation from viable synthetic to quiescent contractile phenotypes. In this study, microfabricated arrays of discontinuous microwalls coated with fluorescence microbeads were developed to probe the mechanotransduction of the SMC layer. First, the system was exploited for stimulating the formation of a highly aligned orientation of SMCs in native tunica medium. Second, atomic force microscopy in combination with regression analysis was applied to measure the elastic modulus of a polyacrylamide gel layer coated on the discontinuous microwall arrays. Third, the conventional traction force assay for single cell measurement was extended for applications in three-dimensional cell aggregates. Then, the biophysical effects of discontinuous microwalls on the mechanotransduction of the SMC layer undergoing cell alignment were probed. Generally, the cooperative multiple cell-cell and cell-microwall interactions were accessed quantitatively by the newly developed assay with the aid of finite-element modelling. The results show that the traction forces of highly aligned cells lying in the middle region between two opposing microwalls were significantly lower than those lying adjacent to the microwalls. Moreover, the spatial distributions of Von Mises stress during the cell alignment process were dependent on the collective cell layer orientation. Immunostaining of the SMC sheet further demonstrated that the collective mechanotransduction induced by three-dimensional topographic cues was correlated with the reduction of actin and vinculin expression. In addition, the online two-dimensional LC-MS/MS analysis verified the modulation of focal adhesion formation under the influence of microwalls through the regulation in the expression of three key cytoskeletal proteins.
Related JoVE Video
Effect of adhesive ligand on cell deadhesion kinetics on poly(N-isopropylacrylamide).
Biomed Mater Eng
PUBLISHED: 03-20-2014
Show Abstract
Hide Abstract
Thermo-responsive poly(N-isopropylacrylamide) (PIPAAm) with a particular lower critical solution temperature (LCST) have been applied for the non-invasive harvesting of confluent cell layer. Until now, the effect of adhesive ligand on the biophysical responses of cells during cell layer harvesting from PIPAAm has not been elucidated. In this study, the deadhesion kinetics of smooth muscle cells (SMC) on various adhesive ligands immobilized on PIPAAm were investigated. Firstly, the formation of elastin (EL), laminin (LA), hyaluronic acid (HA) and collagen (CL) coating on PIPAAm surfaces were validated with XPS, microBCA assay and AFM. It was shown that EL was most effective in driving cell retraction on PIPAAm surface. Moreover, the highest rate of initial SMC deadhesion on EL-PIPAAm was driven by the formation of stress fibers. Interestingly, HA was most effective in preventing initial SMC detachment from PIPAAm surface in comparison with EL, LA and CL. Also, the adhesion energy of SMC on HA-PIPAAm remained constant, which was two times and six times higher than that on CL-PIPAAm and EL-PIPAAm, respectively from 20 min onward. Overall, the results reported herein pave the way for the engineering of the invasive regeneration/recovery of cells/tissue with adhesive ligand.
Related JoVE Video
Adherence to insulin treatment in diabetes: can it be improved?
J Diabetes
PUBLISHED: 03-16-2014
Show Abstract
Hide Abstract
Insulin is used in all subjects with Type 1 diabetes, and when Type 2 diabetes is not controlled by oral anti-diabetic medicines, insulin is also used in Type 2 diabetes. However, despite this use, there is still increased mortality and morbidity in subjects with diabetes, compared to subjects without diabetes. One of the factors, which may be involved in this increased mortality and morbidity in subjects with diabetes, is nonadherence to insulin. Nonadherence rates to insulin are in the range of 20-38%, and many factors contribute to the nonadherence. The major aim of the review was to determine whether interventions to improve adherence to insulin do actually improve adherence to insulin. Most studies have shown that adherence to insulin was improved by changing from the vial-and-syringe approach to prefilled insulin pens, but not all studies have shown that this translated into better glycemic control and clinical outcomes. The results of studies using automatic telephone messages to improve adherence to insulin to date are inconclusive. There is limited and variable evidence that an intervention by a nurse/educator, which discusses adherence to medicines, does improve adherence to insulin. In contrast, there is little or no evidence that an extra intervention by a doctor or an intervention by a pharmacist, which discusses adherence to insulin, does actually improve the measured adherence to insulin. In conclusion, rather than assuming that an intervention by a health professional discussing adherence to insulin actually improves adherence to insulin, long-term studies investigating this are required.
Related JoVE Video
Intra- and interrater reliability of ultrasound assessment of gastric volume.
Anesthesiology
PUBLISHED: 03-06-2014
Show Abstract
Hide Abstract
Gastric sonography can provide information about gastric content and volume that can help determine aspiration risk at the bedside. The primary objective of this study is to assess the intrarater and interrater reliability of a previously validated method of gastric volume assessment based on gastric antral area. The secondary objective is to evaluate the agreement between two different methods to measure gastric antral area.
Related JoVE Video
Contemporary midterm echocardiographic outcomes of Bentall procedure and aortic valve sparing root replacement.
Ann. Thorac. Surg.
PUBLISHED: 02-14-2014
Show Abstract
Hide Abstract
Valve sparing root replacement (VSRR) and aortic valve repair (AVr) is an attractive treatment option compared with composite valve and root replacement (Bentall procedure) for patients with aortic root dilatation with or without aortic valve disease. While aortic valve preservation reduces the risk of valve-related complications, little is known about echocardiographic differences at follow-up between these 2 strategies.
Related JoVE Video
Perioperative deaths after mitral valve operations may be overestimated by contemporary risk models.
Ann. Thorac. Surg.
PUBLISHED: 01-28-2014
Show Abstract
Hide Abstract
Percutaneous therapies to manage mitral regurgitation are emerging as an alternative to conventional operations, especially for patients with a high estimated perioperative risk. However, contemporary risk models may not accurately reflect outcomes at reference mitral valve centers. The purpose of this study was to describe perioperative mortality rates after mitral valve operations in a contemporary cohort.
Related JoVE Video
Clinical impact of mild acute kidney injury after cardiac surgery.
Ann. Thorac. Surg.
PUBLISHED: 01-27-2014
Show Abstract
Hide Abstract
Dialysis-dependent renal failure occurs infrequently after cardiac surgery but leads to substantial morbidity and mortality. In contrast, milder degrees of acute kidney injury (AKI), based on small increases in serum creatinine, occur frequently but the independent impact of mild AKI on outcome remains unclear.
Related JoVE Video
High-risk mitral valve surgery: what is the role of risk calculators?
Curr. Opin. Cardiol.
PUBLISHED: 01-18-2014
Show Abstract
Hide Abstract
The purpose of this review is to discuss the role of established risk scores in assessing patient outcomes following high-risk mitral valve surgery.
Related JoVE Video
The addition of epidural local anesthetic to systemic multimodal analgesia following lumbar spinal fusion: a randomized controlled trial.
Can J Anaesth
PUBLISHED: 01-15-2014
Show Abstract
Hide Abstract
This randomized trial aimed to evaluate the effects of adding continuous epidural analgesia with a bupivacaine and hydromorphone solution to systemic multimodal analgesia following one- or two-level lumbar spinal fusion.
Related JoVE Video
Mitral valve interventions in heart failure.
Curr. Opin. Cardiol.
PUBLISHED: 01-08-2014
Show Abstract
Hide Abstract
This review describes new developments in mitral valve interventions for patients with heart failure. The review also discusses innovative therapies in the treatment of mitral regurgitation in patients with heart failure and describes novel risk factors of recurrent mitral regurgitation following repair in this population.
Related JoVE Video
Proteomics based identification of cell migration related proteins in HBV expressing HepG2 cells.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Proteomics study was performed to investigate the specific protein expression profiles of HepG2 cells transfected with mutant HBV compared with wildtype HBV genome, aiming to identify the specific functions of SH3 binding domain (proline rich region) located in HBx. In addition to the cell movement and kinetics changes due to the expression of HBV genome we have observed previously, here we further targeted to explore the specific changes of cellular proteins and potential intracellular protein interactions, which might provide more information of the potential cellular mechanism of the differentiated cell movements. Specific changes of a number of proteins were shown in global protein profiling in HepG2 cells expressing wildtype HBV, including cell migration related proteins, and interestingly the changes were found recovered by SH3 binding domain mutated HBV. The distinctive expressions of proteins were validated by Western blot analysis.
Related JoVE Video
Regional anesthesia in patients with pregnancy induced hypertension.
J Anaesthesiol Clin Pharmacol
PUBLISHED: 11-20-2013
Show Abstract
Hide Abstract
Pregnancy induced hypertension is a hypertensive disorder, which occurs in 5% to 7% of all pregnancies. These parturients present to the labour and delivery unit ranging from gestational hypertension to HELLP syndrome. It is essential to understand the various clinical conditions that may mimic preeclampsia and the urgency of cesarean delivery, which may improve perinatal outcome. The administration of general anesthesia (GA) increases morbidity and mortality in both mother and baby. The provision of regional anesthesia when possible maintains uteroplacental blood flow, avoids the complications with GA, improves maternal and neonatal outcome. The use of ultrasound may increase the success rate. This review emphasizes on the regional anesthetic considerations when such parturients present to the labor and delivery unit.
Related JoVE Video
Ultrasound-guided sciatic nerve block in overweight and obese patients: a randomized comparison of performance time between the infragluteal and subgluteal space techniques.
Reg Anesth Pain Med
PUBLISHED: 10-15-2013
Show Abstract
Hide Abstract
Despite ultrasound (US) guidance, sciatic nerve block (SNB) remains among the least performed peripheral blocks. By targeting the tissue plane between the gluteus maximus and quadratus femoris muscles, the US-guided subgluteal space technique may facilitate the performance of US-guided SNB. We aimed to evaluate whether the subgluteal space technique shortens SNB performance time in overweight and obese patients compared with the conventional infragluteal technique.
Related JoVE Video
Ischemic mitral regurgitation: current trends and treatment.
Curr. Opin. Cardiol.
PUBLISHED: 10-09-2013
Show Abstract
Hide Abstract
Ischemic mitral regurgitation (MR) is a common finding in patients with coronary artery disease. In this review, we summarize the current literature describing the treatment of ischemic mitral regurgitation.
Related JoVE Video
Functional significance of elevated mitral gradients after repair for degenerative mitral regurgitation.
Circ Cardiovasc Imaging
PUBLISHED: 09-06-2013
Show Abstract
Hide Abstract
Background- We have observed that elevated mitral gradients can develop in some patients after mitral valve repair for degenerative mitral regurgitation. Methods and Results- We screened 275 patients who had mitral valve repair involving >1 leaflet scallop between October 2001 and July 2010. Mitral valve hemodynamics were assessed at rest and at peak exercise using the cycle ergometer. B-type natriuretic peptide levels were measured at rest and after exercise. The patients also performed a 6-minute walk test and short-form 36-Item Health Survey questionnaire. We enrolled 110 patients, with resting mean mitral diastolic gradient of ?3 mm Hg in 35 patients (group 1) and >3 mm Hg indicative of elevated mitral gradients in 75 patients (group 2). Posterior mitral leaflet plication (P=0.04) and the use of a complete mitral annuloplasty ring (P<0.0001) were associated with elevated mitral gradients. Group 2 patients had larger left atrial volume (P=0.02), higher mitral gradients at peak exercise and higher pulmonary artery systolic pressure at rest and at peak exercise, and lower exercise capacity (101±40 versus 122±51 W; P=0.02). Group 2 patients also had higher B-type natriuretic peptide levels and lower scores in 3 short-form 36-Item Health Survey health concepts. Multivariate regression analyses showed that mitral valve area was an independent predictor of maximum exercise capacity (P=0.003). Conclusions- After mitral valve repair for degenerative mitral regurgitation, elevated mitral gradients is not uncommon and is associated with worse intracardiac hemodynamics, higher B-type natriuretic peptide levels, lower exercise capacity, and poorer quality of life. Further refinement in the surgical technique may reduce the incidence of this complication.
Related JoVE Video
The utility of ultrasound imaging in predicting ease of performance of spinal anesthesia in an orthopedic patient population.
Reg Anesth Pain Med
PUBLISHED: 08-03-2013
Show Abstract
Hide Abstract
Ultrasonography of the spine improves technical performance of spinal anesthesia, but what is unclear is whether it can predict difficulty. We tested the hypothesis that a good ultrasound view at a given intervertebral level is associated with absence of technical difficulty.
Related JoVE Video
The impact of analgesic modality on early ambulation following total knee arthroplasty.
Reg Anesth Pain Med
PUBLISHED: 06-14-2013
Show Abstract
Hide Abstract
Total knee arthroplasty is associated with moderate to severe pain, and effective analgesia is essential to facilitate postoperative recovery. This retrospective cohort study examined the analgesic and rehabilitation outcomes associated with 48-hour continuous femoral nerve block, local infiltration analgesia, or local infiltration analgesia plus adductor canal nerve block.
Related JoVE Video
Initial evaluation of a femtosecond laser system in cataract surgery.
J Cataract Refract Surg
PUBLISHED: 05-21-2013
Show Abstract
Hide Abstract
To report the early experience and complications during cataract surgery with a noncontact femtosecond laser system.
Related JoVE Video
Clinical evaluation of functional mitral stenosis after mitral valve repair for degenerative disease: potential affect on surgical strategy.
J. Thorac. Cardiovasc. Surg.
PUBLISHED: 04-27-2013
Show Abstract
Hide Abstract
Mitral annuloplasty with either a partial band or complete ring is an integral part of mitral valve repair for degenerative disease. The affect of annuloplasty type on outcomes has not been well described. The objective of our study was to compare echocardiographic and functional characteristics of patients who underwent mitral repair with either a complete ring or a partial band.
Related JoVE Video
Ultrasound-guided transversus abdominis plane (TAP) block for laparoscopic gastric-bypass surgery:a prospective randomized controlled double-blinded trial.
Obes Surg
PUBLISHED: 04-18-2013
Show Abstract
Hide Abstract
Despite the laparoscopic approach, patients can suffer moderate to severe pain following bariatric surgery. This randomized controlled double-blinded trial investigated the analgesic efficacy of ultrasound-guided transversus abdominis plane (TAP) blocks for laparoscopic gastric-bypass surgery.
Related JoVE Video
Impact of mitral annular calcification on early and late outcomes following mitral valve repair of myxomatous degeneration.
Interact Cardiovasc Thorac Surg
PUBLISHED: 04-14-2013
Show Abstract
Hide Abstract
Mitral annular calcification is associated with significant morbidity and mortality at the time of mitral valve surgery. However, few data are available describing the impact of mitral annular calcification on early and late outcomes following mitral valve repair in the current era.
Related JoVE Video
Ultrasound-guided popliteal block through a common paraneural sheath versus conventional injection: a prospective, randomized, double-blind study.
Reg Anesth Pain Med
PUBLISHED: 04-06-2013
Show Abstract
Hide Abstract
The macroscopic anatomy of a common paraneural sheath that surrounds the sciatic nerve in the popliteal fossa has been studied recently in a human cadaveric study. It has been suggested that an injection through this sheath could be an ideal location for local anesthetic administration for popliteal block. The aim of the present study was to evaluate the hypothesis that popliteal sciatic nerve blockade through a common paraneural sheath results in shorter onset time when compared with conventional postbifurcation injection external to the paraneural tissue. To illustrate the microscopic anatomy of the paraneural tissues, we performed histological examinations of a human leg specimen.
Related JoVE Video
Tailoring the dependency between rigidity and water uptake of a microfabricated hydrogel with the conformational rigidity of a polymer cross-linker.
Biomacromolecules
PUBLISHED: 04-03-2013
Show Abstract
Hide Abstract
Many diverse applications utilize hydrogels as carriers, sensors, and actuators, and these applications rely on the refined control of physical properties of the hydrogel, such as elastic modulus and degree of swelling. Often, hydrogel properties are interdependent; for example, when elastic modulus is increased, degree of swelling is decreased. Controlling these inverse dependencies remains a major barrier for broader hydrogel applications. We hypothesized that polymer cross-linkers with varied chain flexibility would allow us to tune the inverse dependency between the elastic modulus and the degree of swelling of the hydrogels. We examined this hypothesis by using alginate and poly(acrylic acid) (PAA) modified with a controlled number of methacrylic groups as model inflexible and flexible cross-linkers, respectively. Interestingly, the polyacrylamide hydrogel cross-linked by the inflexible alginate methacrylates exhibited less dependency between the degree of swelling and the elastic modulus than the hydrogel cross-linked by flexible PAA methacrylates. This critical role of the cross-linkers inflexibility was related to the difference of the degree of hydrophobic association between polymer cross-linkers, as confirmed with pyrene probes added in pregel solutions. Furthermore, hydrogels cross-linked with alginate methacrylates could tune the projection area of adhered cells by solely altering elastic moduli. In contrast, gels cross-linked with PAA methacrylates failed to modulate the cellular adhesion morphology due to a lower, and smaller, elastic modulus range to be controlled. Overall, the results of this study will significantly advance the controllability of hydrogel properties and greatly enhance the performance of hydrogels in various biological applications.
Related JoVE Video
Enabling microscale and nanoscale approaches for bioengineered cardiac tissue.
ACS Nano
PUBLISHED: 03-27-2013
Show Abstract
Hide Abstract
In this issue of ACS Nano, Shin et al. present their finding that the addition of carbon nanotubes (CNT) in gelatin methacrylate (GelMA) results in improved functionality of bioengineered cardiac tissue. These CNT-GelMA hybrid materials demonstrate cardiac tissue with enhanced electrophysiological performance; improved mechanical integrity; better cell adhesion, viability, uniformity, and organization; increased beating rate and lowered excitation threshold; and protective effects against cardio-inhibitory and cardio-toxic drugs. In this Perspective, we outline recent progress in cardiac tissue engineering and prospects for future development. Bioengineered cardiac tissues can be used to build "heart-on-a-chip" devices for drug safety and efficacy testing, fabricate bioactuators for biointegrated robotics and reverse-engineered life forms, treat abnormal cardiac rhythms, and perhaps one day cure heart disease with tissue and organ transplants.
Related JoVE Video
Current readings: status of tricuspid valve repair.
Semin. Thorac. Cardiovasc. Surg.
PUBLISHED: 02-20-2013
Show Abstract
Hide Abstract
The surgical management of mitral and aortic valvular heart disease has changed significantly over the last decade. Meanwhile, tricuspid valve (TV) surgery has remained less commonly performed than left-sided valve surgeries, and there is a relative paucity of reports in the literature. There are ongoing controversies as to the optimal surgical management of TV disease, including repair versus replacement, the type of prosthesis preferred, optimal repair techniques, appropriate management of functional tricuspid regurgitation (TR) with concomitant left heart valve surgery, and others. In this article, we review what we believe are five important and contemporary papers that cover important aspects of TV surgery and provide recommendations for the surgical management of TV disease.
Related JoVE Video
Cardiomyocyte imaging using real-time spatial light interference microscopy (SLIM).
PLoS ONE
PUBLISHED: 01-16-2013
Show Abstract
Hide Abstract
Spatial light interference microscopy (SLIM) is a highly sensitive quantitative phase imaging method, which is capable of unprecedented structure studies in biology and beyond. In addition to the ?/2 shift introduced in phase contrast between the scattered and unscattered light from the sample, 4 phase shifts are generated in SLIM, by increments of ?/2 using a reflective liquid crystal phase modulator (LCPM). As 4 phase shifted images are required to produce a quantitative phase image, the switching speed of the LCPM and the acquisition rate of the camera limit the acquisition rate and, thus, SLIMs applicability to highly dynamic samples. In this paper we present a fast SLIM setup which can image at a maximum rate of 50 frames per second and provide in real-time quantitative phase images at 50/4?=?12.5 frames per second. We use a fast LCPM for phase shifting and a fast scientific-grade complementary metal oxide semiconductor (sCMOS) camera (Andor) for imaging. We present the dispersion relation, i.e. decay rate vs. spatial mode, associated with dynamic beating cardiomyocyte cells from the quantitative phase images obtained with the real-time SLIM system.
Related JoVE Video
Validation of a mathematical model for ultrasound assessment of gastric volume by gastroscopic examination.
Anesth. Analg.
PUBLISHED: 01-09-2013
Show Abstract
Hide Abstract
Pulmonary aspiration of gastric contents is a serious perioperative complication. Previous models of ultrasound gastric volume assessment are preliminary and have not been validated by an external "gold standard." In the present study we propose a more accurate model based on prospective data obtained from 108 patients undergoing bedside gastric sonography and upper gastrointestinal endoscopy (UGE).
Related JoVE Video
Multi-material bio-fabrication of hydrogel cantilevers and actuators with stereolithography.
Lab Chip
PUBLISHED: 11-29-2011
Show Abstract
Hide Abstract
Cell-based biohybrid actuators are integrated systems that use biological components including proteins and cells to power material components by converting chemical energy to mechanical energy. The latest progress in cell-based biohybrid actuators has been limited to rigid materials, such as silicon and PDMS, ranging in elastic moduli on the order of mega (10(6)) to giga (10(9)) Pascals. Recent reports in the literature have established a correlation between substrate rigidity and its influence on the contractile behavior of cardiomyocytes (A. J. Engler, C. Carag-Krieger, C. P. Johnson, M. Raab, H. Y. Tang and D. W. Speicher, et al., J. Cell Sci., 2008, 121(Pt 22), 3794-3802, P. Bajaj, X. Tang, T. A. Saif and R. Bashir, J. Biomed. Mater. Res., Part A, 2010, 95(4), 1261-1269). This study explores the fabrication of a more compliant cantilever, similar to that of the native myocardium, with elasticity on the order of kilo (10(3)) Pascals. 3D stereolithographic technology, a layer-by-layer UV polymerizable rapid prototyping system, was used to rapidly fabricate multi-material cantilevers composed of poly(ethylene glycol) diacrylate (PEGDA) and acrylic-PEG-collagen (PC) mixtures. The incorporation of acrylic-PEG-collagen into PEGDA-based materials enhanced cell adhesion, spreading, and organization without altering the ability to vary the elastic modulus through the molecular weight of PEGDA. Cardiomyocytes derived from neonatal rats were seeded on the cantilevers, and the resulting stresses and contractile forces were calculated using finite element simulations validated with classical beam equations. These cantilevers can be used as a mechanical sensor to measure the contractile forces of cardiomyocyte cell sheets, and as an early prototype for the design of optimal cell-based biohybrid actuators.
Related JoVE Video
Heart valve prosthesis selection in patients with end-stage renal disease requiring dialysis: a systematic review and meta-analysis.
Heart
PUBLISHED: 10-11-2011
Show Abstract
Hide Abstract
There is little evidence guiding heart valve prosthesis selection in patients with end-stage renal disease (ESRD) on dialysis.
Related JoVE Video
Ultrasound-guided versus anatomic landmark-guided ankle blocks: a 6-year retrospective review.
Reg Anesth Pain Med
PUBLISHED: 09-24-2011
Show Abstract
Hide Abstract
Ultrasound-guided (USG) ankle block has been described; however, its clinical efficacy compared with conventional anatomic landmark-guided (ALG) techniques remains undetermined.
Related JoVE Video
Reoperation of left heart valve bioprostheses according to age at implantation.
Circulation
PUBLISHED: 09-14-2011
Show Abstract
Hide Abstract
Evidence supporting the use of bioprostheses for heart valve replacement in young adults is accumulating. However, reoperation data, which may help guide clinical decision making in young patients, remains poorly defined in the literature.
Related JoVE Video
Resveratrol improves cardiovascular function in DOCA-salt hypertensive rats.
Curr Pharm Biotechnol
PUBLISHED: 08-30-2011
Show Abstract
Hide Abstract
The phytoalexin resveratrol (3,4,5-trihydroxy-trans-stilbene) may attenuate cardiovascular disease in man. This study has determined whether treatment with resveratrol (1 mg/kg/day orally) prevented cardiac fibrosis and the decreased cardiovascular function in the DOCA-salt hypertensive rat as a model of human hypertension. Uninephrectomised rats (UNX) administered DOCA (25mg every 4th day sc) and 1% NaCl in drinking water for 28 days developed cardiac and vascular remodelling. In these DOCA-salt rats, resveratrol decreased inflammatory cell infiltration, decreased cardiac fibrosis (left ventricular interstitial and perivascular collagen content) and improved cardiac and vascular function. Resveratrol attenuated other features of cardiovascular remodelling such as increases in systolic blood pressure, left ventricular wet weight, left ventricular wall thickness, diastolic stiffness constant, as well as decreased cardiac contractility and prolonged action potential duration characteristic of DOCA-salt rats. In summary, resveratrol, at a nutritionally relevant dose, prevents or attenuates the adverse changes in the cardiovascular system. We propose that the anti-inflammatory and anti-fibrotic effects of resveratrol are responsible, at least in part, for its amelioration in cardiovascular remodelling in DOCA-salt rats. These actions of resveratrol could play an important role in the protective effects on the human cardiovascular system reported for this constituent of red wine.
Related JoVE Video
Chronic ?-adrenoceptor antagonist treatment controls cardiovascular remodeling in heart failure in the aging spontaneously hypertensive rat.
J. Cardiovasc. Pharmacol.
PUBLISHED: 06-29-2011
Show Abstract
Hide Abstract
Selective ?1-adrenoceptor antagonists are part of standard therapy to prolong survival in human heart failure. This study has measured structural, functional, and electrical changes in the cardiovascular system of aging male spontaneously hypertensive rats (SHRs) to determine whether ?1-adrenoceptor antagonist treatment can prevent or reverse the development of cardiovascular remodeling and heart failure in these rats. Fifteen-month-old male Wistar-Kyoto (WKY) rats or SHRs were treated with increasing metoprolol doses (30 mg·kg·d for 4 weeks, then 50 mg·kg·d for 4 weeks, then 80 mg·kg·d for 16 weeks po). Cardiovascular structure and function were determined using organ wet weight, in vivo echocardiography, histological analysis of inflammation and collagen, isolated heart and thoracic aortic ring preparations, and single cell microelectrode measurements. From 15 months, untreated SHRs developed left ventricular dilation, hypertrophy, inflammatory cell infiltration and fibrosis, and action potential prolongation together with progressive systolic, diastolic, and endothelial dysfunction and increased cardiac stiffness. Treatment with metoprolol decreased systolic blood pressure at 21 months only but improved survival, decreased ventricular weight, prevented chamber dilation, reduced inflammation, decreased fibrosis, attenuated action potential prolongation, improved systolic and diastolic function, decreased stiffness and improved endothelium-independent vascular responses. Chronic metoprolol treatment markedly attenuated both cardiac and vascular remodeling in the aging SHRs, thus attenuating the onset of heart failure and improving survival, independent of blood pressure reduction.
Related JoVE Video
Comparison of sonography and computed tomography as imaging tools for assessment of airway structures.
J Ultrasound Med
PUBLISHED: 06-28-2011
Show Abstract
Hide Abstract
The aim of this study was to compare airway anatomic parameters as measured by sonography and computed tomography (CT).
Related JoVE Video
Label-free imaging of cell attachment with photonic crystal enhanced microscopy.
Analyst
PUBLISHED: 06-21-2011
Show Abstract
Hide Abstract
We introduce photonic crystal enhanced microscopy (PCEM) as a label-free biosensor imaging technique capable of measuring cell surface attachment and attachment modulation. The approach uses a photonic crystal optical resonator surface incorporated into conventional microplate wells and a microscope-based detection instrument that measures shifts in the resonant coupling conditions caused by localized changes in dielectric permittivity at the cell-sensor interface. Four model systems are demonstrated for studying cancer cells, primary cardiac muscle cells, and stem cells. First, HepG2/C3 hepatic carcinoma cells were cultured and observed via PCEM in order to characterize cell adhesion in the context of growth and locomotion. Second, Panc-1 pancreatic cancer cells were used to verify that cell attachment density decreases in response to staurosporine, a drug that induces apoptosis. Third, we used PCEM to confirm the influence of integrin-mediated signaling on primary neonatal cardiomyocyte growth and development. Rounded cardiomyocytes consistently showed decreased cell attachment density as recorded via PCEM, while spreading cells exhibited greater attachment strength as well as increased contractility. Finally, PCEM was used to monitor the morphological changes and extracellular matrix remodeling of porcine adipose-derived stem cells subjected to a forced differentiation protocol. Each of these experiments yielded information regarding cell attachment density without the use of potentially cytotoxic labels, enabling study of the same cells for up to several days.
Related JoVE Video
Ultrasound-guided transversus abdominis plane (TAP) block: a useful adjunct in the management of postoperative respiratory failure.
J Clin Anesth
PUBLISHED: 06-14-2011
Show Abstract
Hide Abstract
The ultrasound-guided transversus abdominis plane (TAP) block is a useful tool in controlling postoperative pain following abdominal surgery. The bilateral ultrasound-guided TAP blocks successfully managed the pain of a patient presenting with hypoxemia and respiratory failure in the Post-anesthesia Care Unit, following a laparotomy for small bowel obstruction during general anesthesia. The TAP block reduced systemic opioid requirements and opioid-induced sedation and respiratory depression, improved patient compliance with non-invasive positive pressure ventilation, and prevented the need for intubation and ventilation in the intensive care unit.
Related JoVE Video
Long-term evaluation of biological versus mechanical prosthesis use at reoperative aortic valve replacement.
J. Thorac. Cardiovasc. Surg.
PUBLISHED: 05-31-2011
Show Abstract
Hide Abstract
Recent evidence indicated that the use of a bioprosthesis in young patients at first-time aortic valve replacement (AVR) is associated with an increased reoperation risk, but not with an increase in long-term mortality, when compared with the use of a mechanical valve. However, at reoperative AVR, follow-up data by prosthesis type have been lacking from the literature. Therefore, we examined long-term survival and valve-related complications according to the type of prosthesis used at reoperative AVR.
Related JoVE Video
Gastric sonography in the fasted surgical patient: a prospective descriptive study.
Anesth. Analg.
PUBLISHED: 05-19-2011
Show Abstract
Hide Abstract
Aspiration pneumonia remains a serious anesthetic-related complication. A reliable diagnostic tool to assess gastric volume is currently lacking. We recently demonstrated that gastric sonography can provide reliable qualitative and quantitative information about gastric content and volume in healthy volunteers. In the current study, we performed a prospective qualitative and quantitative analysis of the gastric antrum in 200 fasted patients undergoing elective surgery.
Related JoVE Video
Ultrasound imaging facilitates spinal anesthesia in adults with difficult surface anatomic landmarks.
Anesthesiology
PUBLISHED: 05-17-2011
Show Abstract
Hide Abstract
Poor surface anatomic landmarks are highly predictive of technical difficulty in neuraxial blockade. The authors examined the use of ultrasound imaging to reduce this difficulty.
Related JoVE Video
Echotexture and correlated histologic analysis of peripheral nerves important in regional anesthesia.
Reg Anesth Pain Med
PUBLISHED: 05-11-2011
Show Abstract
Hide Abstract
Peripheral nerves in different body locations display different echotextures on ultrasound imaging, and knowledge of peripheral nerve echotexture is helpful for locating target nerves. However, the degree of echogenicity is often difficult to characterize. We aimed to define objectively the degree of echogenicity of peripheral nerves using grayscale measurements and compare nerve echotexture with matched histologic samples.
Related JoVE Video
Lateral versus medial needle approach for ultrasound-guided supraclavicular block: a randomized controlled trial.
Reg Anesth Pain Med
PUBLISHED: 05-11-2011
Show Abstract
Hide Abstract
When performing a supraclavicular brachial plexus block (SCB) under ultrasound (US) guidance, the needle may approach the nerves in-plane with the US beam from 1 of 2 directions relative to the transducer, lateral-to-medial (lateral) or medial-to-lateral (medial). We aimed to compare the rates of sensory and motor block of the 4 major peripheral nerves of the upper extremity following a lateral or medial needle approach for US-guided SCB.
Related JoVE Video
Off-pump coronary artery bypass grafting does not preserve renal function better than on-pump coronary artery bypass grafting: results of a case-matched study.
J. Thorac. Cardiovasc. Surg.
PUBLISHED: 05-09-2011
Show Abstract
Hide Abstract
Controversy exists regarding the perioperative renal effects of off-pump versus on-pump coronary artery bypass grafting. Large case-matched and randomized comparisons have shown conflicting results. This study focuses on this clinical controversy.
Related JoVE Video
Hand motion analysis using the imperial college surgical assessment device: validation of a novel and objective performance measure in ultrasound-guided peripheral nerve blockade.
Reg Anesth Pain Med
PUBLISHED: 04-27-2011
Show Abstract
Hide Abstract
The Imperial College Surgical Assessment Device (ICSAD) has been validated in various settings as an objective tool to measure technical performance. We sought to establish (1) the construct validity of the ICSAD as an assessment tool in ultrasound-guided supraclavicular block by determining its ability to discriminate between operators of different experience level and (2) the concurrent validity of the ICSAD by correlating it with a task-specific checklist and a global rating scale.
Related JoVE Video
Is circumferential injection advantageous for ultrasound-guided popliteal sciatic nerve block?: A proof-of-concept study.
Reg Anesth Pain Med
PUBLISHED: 04-15-2011
Show Abstract
Hide Abstract
Ultrasound (US) guidance, in some instances, can increase the success rate and reduce the onset and procedure times for peripheral nerve blockade compared with traditional nerve localization techniques. The presumptive mechanism for these benefits is the ability to accurately inject local anesthetic circumferentially around the target nerve. We aimed to determine whether ensuring circumferential spread of local anesthetic is advantageous for US-guided popliteal sciatic nerve block.
Related JoVE Video
Biomechanical study of the edge outgrowth phenomenon of encapsulated chondrocytic isogenous groups in the surface layer of hydrogel scaffolds for cartilage tissue engineering.
Acta Biomater
PUBLISHED: 04-13-2011
Show Abstract
Hide Abstract
In cartilage tissue engineering, hydrogel is widely used as the scaffold for hosting and culturing chondrocyte suspension during neo-tissue formation. In order to develop cultured chondrocytes into a functional cartilage equivalent, the hydrogel must provide an ideal microenvironment for the rapidly proliferating chondrocytes. At the same time, the essential functions of chondrocytes, such as the secretion of type II collagen and glycosaminoglycans, must be maintained. In these studies, we quantitatively characterize the mechanobiology underlying a newly discovered "edge flourish" phenomenon of cultured chondrocytes within a three-dimensional agarose hydrogel, which may ultimately nurture scaffold-free cartilaginous tissue regeneration. First, real-time microscopy was used to track the spatiotemporal distributions of chondrocytes at different focal planes. The chondrocytes were observed to exhibit abundant neo-tissue outgrowth and significant cartilaginous phenotype at the edge of the hydrogel compared to those inside the hydrogel bulk. Secondly, the hydrogel surface stresses induced by the encapsulated chondrocytes were characterized quantitatively in real time using the finite-element method. Finally, the real-time three-dimensional matrix deformations of agarose hydrogel under the influence of chondrocytes were measured using a multiple-particle tracking assay. Our results indicate that the mechanism of the "edge flourish" phenomenon is induced by the oriented outgrowth of chondrocytic isogenous groups located at the edge of hydrogel. These isogenous groups exhibit directed outgrowth towards the surface of the hydrogel and eventually generate substantial surface tension on the interface of hydrogel and medium. Ultimately, the encapsulated chondrocytes closest to the hydrogel/medium interface will spontaneously sprout out of the hydrogel and form a layer of rich proliferative and chondrocytic extracellular matrix secreting chondrocytes at the surface of the hydrogel.
Related JoVE Video
Epigallocatechin-3-gallate induced modulation of cell deadhesion and migration on thermosensitive poly(N-isopropylacrylamide).
J Biomed Mater Res A
PUBLISHED: 04-11-2011
Show Abstract
Hide Abstract
Epigallocatechin-3-gallate (EGCG), which is the main polyphenolic constituent of green tea, has emerged as a promising candidate for potential applications in selected anticancer therapeutics. Generally, tumor metastasis is known to be correlated with the alterations in cell adhesion and migration of normal cells. Nevertheless, the effect of EGCG on the biophysical responses of tumor cell adhering on extracellular matrix remains obscure. In this study, a thermosenstive poly(N-isopropylacrylamide) (PIPAAm) system was developed to elucidate the potential anti-tumor effect of EGCG on the deadhesion and migration of HepG2 cells. First, both XPS and ELISA validated the coating of laminin (LA) on PIPAAm. Second, a change of nanotopology of LA layer on PIPAAm across the lower solution critical temperature (LCST) was detected with AFM. HepG2 cells seeded on LA-coated PIPAAm surface was shown to go through deadhesion by lowering the temperature below the LCST. Interestingly, EGCG was shown to decelerate the thermally triggered deadhesion of HepG2 cell on LA coated PIPAAm. Moreover, the inhibition of cell deadhesion in EGCG treated cells was shown to be driven by actin remodeling. Interestingly, the modulation of cell deadhesion on LA coated PIPAAm by EGCG leads to the reduction of cell motility as shown by real-time cell migration assay. Overall, the use of PIPAAm system demonstrated the promise of EGCG as anticancer therapy through the suppression of cell deadhesion and migration.
Related JoVE Video
Experimental and numerical determination of cellular traction force on polymeric hydrogels.
Interface Focus
PUBLISHED: 04-02-2011
Show Abstract
Hide Abstract
Anchorage-dependent cells such as smooth muscle cells (SMCs) rely on the transmission of actomyosin-generated traction forces to adhere and migrate on the extracellular matrix. The cellular traction forces exerted by SMCs on substrate can be measured from the deformation of substrate with embedded fluorescent markers. With the synchronous use of phase-contrast and fluorescent microscopy, the deformation of polyacrylamide (PAM) gel substrate can be quantitatively determined using particle image velocimetry. This displacement map is then input as boundary conditions for the stress analysis on PAM gel by the finite-element method. In addition to optical microscopy, atomic force microscopy was also used to characterize the PAM substrate using the contact mode, from which the elasticity of PAM can be quantified using Hertzian theory. This provides baseline information for the stress analysis of PAM gel deformation. The material model introduced for the computational part is the Mooney-Rivlin constitutive law because of its long proven usefulness in predicting polymers mechanical behaviour. Numerical results showed that adhesive stresses are high around the cell edges, which is in accordance with the general phenomena of cellular focal adhesion. Further calculations on the total traction forces indicate a slightly contact-dominated regime for a broad range of Mooney-Rivlin stiffnesses.
Related JoVE Video
Characterization of mitral valve prolapse with cardiac computed tomography: comparison to echocardiographic and intraoperative findings.
Int J Cardiovasc Imaging
PUBLISHED: 03-18-2011
Show Abstract
Hide Abstract
A single imaging modality that can accurately assess both coronary anatomy and mitral valve (MV) anatomy prior to surgery may be desirable. We sought to determine the diagnostic accuracy of cardiac computed tomography (CT) to detect and characterize mitral valve prolapse (MVP) compared to echocardiography. Consecutive patients referred for single-source cardiac CT for investigation prior to non-coronary cardiac sugery were identified. MV anatomy was assessed for MVP and results were compared to echocardiography and to intra-operative visual assessment of the MV. Comparison between the three modalities was performed at the per-patient, per-leaflet and per-scallop levels. A total of 67 consecutive patients that were referred for Cardiac CT prior to non-coronary cardiac surgery and were prospectively recruited into a Cardiac CT registry. Of these, 65 patients underwent cardiac surgery. 63 patients had echocardiography and 32 patients had intra-operative visual assessment of the mitral valve. Compared to echocardiography, cardiac CT had excellent sensitivity (92.6%) and specificity (97.1%) for the detection of any MVP, but had poor sensitivity (68.5%) for the detection of individual prolapsing scallop. Compared to intra-operative visual assessment of the prolapsing scallop, both cardiac CT and echocardiography had low sensitivity (58.1 and 78.1%, respectively). Cardiac CT was able to identify patients with MVP but had difficulty identifying the prolapsed scallops compared to echocardiography. Single-source CT may not be ready for characterization of individual mitral valve scallops.
Related JoVE Video
Label-free intracellular transport measured by spatial light interference microscopy.
J Biomed Opt
PUBLISHED: 03-03-2011
Show Abstract
Hide Abstract
We show that applying the Laplace operator to a speckle-free quantitative phase image reveals an unprecedented level of detail in cell structure, without the gradient artifacts associated with differential interference contrast microscopy, or photobleaching and phototoxicity limitations common in fluorescence microscopy. This method, referred to as Laplace phase microscopy, is an efficient tool for tracking vesicles and organelles in living cells. The principle is demonstrated by tracking organelles in cardiomyocytes and vesicles in neurites of hippocampal neurons, which to our knowledge are the first label-free diffusion measurements of the organelles in such cells.
Related JoVE Video
Aligned 3D human aortic smooth muscle tissue via layer by layer technique inside microchannels with novel combination of collagen and oxidized alginate hydrogel.
J Biomed Mater Res A
PUBLISHED: 02-13-2011
Show Abstract
Hide Abstract
Tissue engineering of the small diameter blood vessel medial layer has been challenging. Recreation of the circumferentially aligned multilayer smooth muscle tissue has been one of the major technical difficulties. Some research has utilized cyclic stress to align smooth muscle cells (SMCs) but due to the long time conditioning needed, it was not possible to use primary human cells because of expeditious senescence occurred . We demonstrate rapid buildup of a homogeneous relatively thick (30-40 ?m) aligned smooth muscle tissue via layer by layer (LBL) technique within microchannels and a soft cell-adhesive hydrogel. Using a microchannelled scaffold with gapped microwalls, two layers of primary human SMCs separated by an interlayer hydrogel were cultured to confluence within the microchannels. The SMCs aligned along the microchannels because of the physically constraining microwalls. A novel double layered gel consisting of a mixture of pristine and oxidized alginate hydrogel coated with collagen was designed to place between each layer of cells, leading to a thicker tissue in a shorter time. The SMCs penetrated the soft thin interlayer hydrogel within 6 days of seeding of the 2nd cell layer so that the entire construct became more or less homogeneously populated by the SMCs. The unique LBL technique applied within the micropatterned scaffold using a soft cell-adhesive gel interlayer allows rapid growth and confluence of SMCs on 2D surface but at the same time aligns the cells and builds up multiple layers into a 3D tissue. This pseudo-3D buildup method avoids the typical steric resistance of hydrogel embedding.
Related JoVE Video
Predictors of liver transplant eligibility for patients with hepatocellular carcinoma in a safety net hospital.
Dig. Dis. Sci.
PUBLISHED: 02-10-2011
Show Abstract
Hide Abstract
Liver transplantation for patients with hepatocellular carcinoma (HCC) affords excellent long-term survival but is limited to patients with early stage tumors. Predictors for orthotopic liver transplantation eligibility are not well defined for patients in a safety-net hospital system.
Related JoVE Video
Mitral valve replacement is a viable alternative to mitral valve repair for ischemic mitral regurgitation: a case-matched study.
Ann. Thorac. Surg.
PUBLISHED: 02-02-2011
Show Abstract
Hide Abstract
Comparisons of mitral valve repair with mitral valve replacement for ischemic mitral regurgitation (IMR) have been limited by differences in preoperative and operative characteristics of patients undergoing these two types of surgical treatment. We performed a propensity-based, case-matched analysis to examine whether patients who undergo mitral valve repair and those who undergo mitral valve replacement for IMR have similar long-term outcomes.
Related JoVE Video
Is a patella motor response necessary for continuous femoral nerve blockade performed in conjunction with ultrasound guidance?
Anesth. Analg.
PUBLISHED: 02-02-2011
Show Abstract
Hide Abstract
Successful continuous femoral nerve blockade (CFNB) has been associated with the elicitation of a patella motor response during needle and catheter insertion. We evaluated whether a patella motor response is necessary when CFNB is performed in conjunction with ultrasound (US) guidance.
Related JoVE Video
Cardiovascular changes during maturation and ageing in male and female spontaneously hypertensive rats.
J. Cardiovasc. Pharmacol.
PUBLISHED: 02-02-2011
Show Abstract
Hide Abstract
Cardiovascular remodeling leading to heart failure is common in the elderly. Testing effective pharmacological treatment of human heart failure requires a suitable animal model that adequately mimics the human disease state.
Related JoVE Video
Minimally invasive coronary artery bypass grafting via a small thoracotomy versus off-pump: a case-matched study.
Eur J Cardiothorac Surg
PUBLISHED: 01-13-2011
Show Abstract
Hide Abstract
The minimally invasive coronary artery bypass grafting (MICS CABG) operation performed via a small thoracotomy has not previously been examined in a direct comparison to sternotomy off-pump coronary artery bypass grafting (OPCAB).
Related JoVE Video
Tropheryma whipplei aortic valve endocarditis without systemic Whipples disease.
Int. J. Infect. Dis.
PUBLISHED: 01-03-2011
Show Abstract
Hide Abstract
Culture-negative endocarditis is most often the result of prior antimicrobial therapy. Tropheryma whipplei is the etiologic agent of Whipples disease, which is typically characterized by diarrhea, weight loss, and intra-abdominal lymphadenopathy. We present the case of a 48-year-old male with Whipples endocarditis of the aortic valve who did not develop signs of systemic Whipples disease. Our patient was treated with a regimen that included ceftriaxone for 6 weeks prior to his cardiac surgery, yet valve pathology demonstrated abundant T. whipplei, suggesting that a prolonged antibiotic course is necessary for the treatment of Whipples endocarditis.
Related JoVE Video
Frequency and surgical management of complex posterior leaflet prolapse of the mitral valve.
J. Heart Valve Dis.
PUBLISHED: 11-09-2010
Show Abstract
Hide Abstract
Isolated posterior leaflet prolapse of the mitral valve may present with more complex anatomy than limited middle scallop prolapse (P2). The study aim was to describe the incidence and surgical management of extensive or commissural posterior leaflet prolapse, in addition to long-term outcomes following repair.
Related JoVE Video
Clinical sonopathology for the regional anesthesiologist: part 2: bone, viscera, subcutaneous tissue, and foreign bodies.
Reg Anesth Pain Med
PUBLISHED: 10-06-2010
Show Abstract
Hide Abstract
The use of ultrasound to facilitate regional anesthesia is an evolving area of clinical, education, and research interests. As our communitys experience grows, it has become evident that anesthesiologists performing "routine" ultrasound-guided blocks may very well be confronted with atypical or even pathologic anatomy. As an educational resource for anesthesiologists, the following articles present examples of common sonopathology that may be encountered during ultrasound-guided regional anesthesia. This present article describes sonopathology related to bone, viscera, and subcutaneous tissue.
Related JoVE Video
Clinical sonopathology for the regional anesthesiologist: part 1: vascular and neural.
Reg Anesth Pain Med
PUBLISHED: 10-06-2010
Show Abstract
Hide Abstract
The use of ultrasound to facilitate regional anesthesia is an evolving area of clinical, education, and research interests. As our communitys experience grows, it has become evident that anesthesiologists performing "routine" ultrasound-guided blocks may very well be confronted with atypical or even pathologic anatomy. As an educational resource for anesthesiologists, the following articles present examples of common sonopathology that may be encountered during ultrasound-guided regional anesthesia. This present article describes sonopathology related to blood vessels and nerves.
Related JoVE Video
Ultrasound-guided popliteal block distal to sciatic nerve bifurcation shortens onset time: a prospective randomized double-blind study.
Reg Anesth Pain Med
PUBLISHED: 10-06-2010
Show Abstract
Hide Abstract
Popliteal sciatic nerve block (SNB) in combination with saphenous nerve block provides anesthesia and analgesia for foot and ankle surgeries. Landmark-based and image-guided techniques, to date, aim at blocking the sciatic nerve proximal to its bifurcation. Sciatic nerve block is usually associated with a long onset time (30-60 mins). We hypothesized that SNB distal to its bifurcation (blocking its 2 main branches tibial and common peroneal nerves separately) is associated with a shorter onset time than blockade proximal to its bifurcation.
Related JoVE Video

What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.