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Find video protocols related to scientific articles indexed in Pubmed.
Non-invasive vulnerable plaque imaging: how do we know that treatment works?
Eur Heart J Cardiovasc Imaging
PUBLISHED: 05-29-2014
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Atherosclerosis is an inflammatory disorder that can evolve into an acute clinical event by plaque development, rupture, and thrombosis. Plaque vulnerability represents the susceptibility of a plaque to rupture and to result in an acute cardiovascular event. Nevertheless, plaque vulnerability is not an established medical diagnosis, but rather an evolving concept that has gained attention to improve risk prediction. The availability of high-resolution imaging modalities has significantly facilitated the possibility of performing in vivo regression studies and documenting serial changes in plaque stability. This review summarizes the currently available non-invasive methods to identify vulnerable plaques and to evaluate the effects of the current cardiovascular treatments on plaque evolution.
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Growth inhibition, cell-cycle alteration and apoptosis in stimulated human peripheral blood lymphocytes by multiwalled carbon nanotube buckypaper.
Nanomedicine (Lond)
PUBLISHED: 05-15-2014
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Aim: This study was designed to investigate the cytotoxicity of multiwalled carbon nanotube buckypaper (BP) in stimulated human peripheral blood lymphocytes. Methods & results: BP treatment led to a delay in the cell growth, as proven by a minor increase in the cell number over time relative to that seen in untreated cells, assessed by trypan blue, resazurin and neutral red assays. The analysis of cell-cycle profile, by propidium iodide staining, indicated that BP treatment blocked cell-cycle progression by arresting cells at the G0/G1 phase. Moreover, increased apoptosis was also recorded by Annexin V-fluorescein isothiocyanate/propidium iodide staining. Conclusion: The results presented here demonstrate an inhibitor effect of BP on cell growth that was likely through cytostatic and cytotoxic events. Original submitted 21 June 2013; Revised submitted 10 January 2014.
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Meta-analysis of mortality outcomes and mitral regurgitation evolution in 4,839 patients having transcatheter aortic valve implantation for severe aortic stenosis.
Am. J. Cardiol.
PUBLISHED: 04-29-2014
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Transcatheter aortic valve implantation (TAVI) is an effective alternative therapy in selected patients with severe aortic stenosis. The role and effects of coexistent moderate to severe mitral regurgitation (msMR) in patients who undergo TAVI remain unclear. Thirteen studies enrolling 4,839 patients who underwent TAVI, including patients with msMR, were considered in a meta-analysis and analyzed for all-cause-mortality; a further meta-analysis was performed to assess mitral regurgitation (MR) evolution after TAVI. In patients with msMR, all-cause-mortality after TAVI was significantly increased at 30-day (effect size [ES] -0.18, 95% confidence interval [CI] -0.31 to -0.04, I(2) = 46.51, Q = 7.48), 1-year (ES -0.22, 95% CI -0.36 to -0.08, I(2) = 56.20, Q = 11.41), and 2-year (ES -0.15, 95% CI -0.27 to -0.02, I(2) = 0.00, Q = 2.64) follow-up compared with patients with absent or mild MR, independent of baseline left ventricular ejection fraction. Interestingly, the impact of msMR on outcomes was statistically stronger when the CoreValve system was used. TAVI was also associated with an improvement in MR entity at 3- and 6-month follow-up (overall ES -0.19, 95% CI -0.37 to -0.01, I(2) = 61.52, Q = 10.39). In conclusion, the presence of preoperative msMR in patients with severe, symptomatic aortic stenosis who undergo TAVI negatively affects outcomes after TAVI. In addition, in the same group of patients, a trend toward a reduction in MR severity was observed. Whether the decrease in MR severity affects mortality after TAVI remains to be defined.
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Cerebral embolic lesions detected with diffusion-weighted magnetic resonance imaging following carotid artery stenting: a meta-analysis of 8 studies comparing filter cerebral protection and proximal balloon occlusion.
JACC Cardiovasc Interv
PUBLISHED: 03-28-2014
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The aim of this meta-analysis was to evaluate and compare the efficacy of the 2 different neuroprotection systems in preventing embolization during carotid artery stenting (CAS), as detected by diffusion-weighted magnetic resonance imaging (DW-MRI).
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Increased mortality after transcatheter aortic valve implantation (TAVI) in patients with severe aortic stenosis and low ejection fraction: a meta-analysis of 6898 patients.
Int. J. Cardiol.
PUBLISHED: 01-21-2014
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There is conflicting evidence regarding the safety and efficacy of transcatheter aortic valve implantation (TAVI) procedures in patients with severe aortic stenosis and low left ventricular ejection fraction (EF). The primary aim of this study was to determine the impact of TAVI on short- and long-term mortality in patients with low EF (EF <50%); the secondary aim was to analyze the impact of TAVI procedure on EF recovery in the same setting of patients.
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Adaptive response in human blood lymphocytes exposed to non-ionizing radiofrequency fields: resistance to ionizing radiation-induced damage.
J. Radiat. Res.
PUBLISHED: 08-26-2013
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The aim of this preliminary investigation was to assess whether human peripheral blood lymphocytes which have been pre-exposed to non-ionizing radiofrequency fields exhibit an adaptive response (AR) by resisting the induction of genetic damage from subsequent exposure to ionizing radiation. Peripheral blood lymphocytes from four healthy donors were stimulated with phytohemagglutinin for 24 h and then exposed for 20 h to 1950 MHz radiofrequency fields (RF, adaptive dose, AD) at an average specific absorption rate of 0.3 W/kg. At 48 h, the cells were subjected to a challenge dose (CD) of 1.0 or 1.5 Gy X-irradiation (XR, challenge dose, CD). After a 72 h total culture period, cells were collected to examine the incidence of micronuclei (MN). There was a significant decrease in the number of MN in lymphocytes exposed to RF + XR (AD + CD) as compared with those subjected to XR alone (CD). These observations thus suggested a RF-induced AR and induction of resistance to subsequent damage from XR. There was variability between the donors in RF-induced AR. The data reported in our earlier investigations also indicated a similar induction of AR in human blood lymphocytes that had been pre-exposed to RF (AD) and subsequently treated with a chemical mutagen, mitomycin C (CD). Since XR and mitomycin-C induce different kinds of lesions in cellular DNA, further studies are required to understand the mechanism(s) involved in the RF-induced adaptive response.
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Genetic deletion of uncoupling protein 3 exaggerates apoptotic cell death in the ischemic heart leading to heart failure.
J Am Heart Assoc
PUBLISHED: 05-22-2013
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Uncoupling protein 3 (ucp3) is a member of the mitochondrial anion carrier superfamily of proteins uncoupling mitochondrial respiration. In this study, we investigated the effects of ucp3 genetic deletion on mitochondrial function and cell survival under low oxygen conditions in vitro and in vivo.
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GC/CI-MS/MS method for the identification and quantification of volatile N-nitrosamines in meat products.
Food Chem
PUBLISHED: 01-23-2013
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A sensitive and selective method was developed and validated for the determination of nine N-nitrosamines in meat products. The N-nitrosamines were extracted with NaOH/methanol, partitioned into dichloromethane on a ChemElut column and cleaned-up by solid-phase extraction. All samples were spiked with (2)H isotope-labelled N-nitrosamine internal standard prior to extraction. After purification on a Florisil mini-column, the extracts were analysed by gas chromatography-chemical ionisation tandem mass spectrometry (GC-CI/MS/MS) using ammonia as reagent gas. The presence of N-nitrosamines in samples was quantified by isotope dilution mass spectrometry. The method was validated for linearity and range, accuracy, precision and sensitivity. Recoveries were calculated at three levels of concentration (0.5, 1 and 10 ?g/kg) spiked in raw pork meat. The values were found between 95% and 110% with relative standard deviation (RSD) values between 5% and 11%. The excellent selectivity and sensitivity allows quantification and identification of low levels of N-nitrosamines in meat products (limits of quantitation (LOQs) 0.3-0.4 ?g/kg). Finally, the method was successfully used to analyse a sample of canned meat and nine different cured meat products produced in Italy. N-Nitroso-dimethylamine was detected in all examined products in the range 0.3-1.1 ?g/kg.
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DNA electrophoretic migration patterns change after exposure of Jurkat cells to a single intense nanosecond electric pulse.
PLoS ONE
PUBLISHED: 09-26-2011
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Intense nanosecond pulsed electric fields (nsPEFs) interact with cellular membranes and intracellular structures. Investigating how cells respond to nanosecond pulses is essential for a) development of biomedical applications of nsPEFs, including cancer therapy, and b) better understanding of the mechanisms underlying such bioelectrical effects. In this work, we explored relatively mild exposure conditions to provide insight into weak, reversible effects, laying a foundation for a better understanding of the interaction mechanisms and kinetics underlying nsPEF bio-effects. In particular, we report changes in the nucleus of Jurkat cells (human lymphoblastoid T cells) exposed to single pulses of 60 ns duration and 1.0, 1.5 and 2.5 MV/m amplitudes, which do not affect cell growth and viability. A dose-dependent reduction in alkaline comet-assayed DNA migration is observed immediately after nsPEF exposure, accompanied by permeabilization of the plasma membrane (YO-PRO-1 uptake). Comet assay profiles return to normal within 60 minutes after pulse delivery at the highest pulse amplitude tested, indicating that our exposure protocol affects the nucleus, modifying DNA electrophoretic migration patterns.
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Induction of adaptive response in human blood lymphocytes exposed to 900 MHz radiofrequency fields: influence of cell cycle.
Int. J. Radiat. Biol.
PUBLISHED: 05-11-2011
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To investigate the influence of cell cycle on the adaptive response (AR) induced by the exposure of human blood lymphocytes to radiofrequency fields (RF).
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EGFR trans-activation by urotensin II receptor is mediated by ?-arrestin recruitment and confers cardioprotection in pressure overload-induced cardiac hypertrophy.
Basic Res. Cardiol.
PUBLISHED: 02-10-2011
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Urotensin II (UTII) and its seven trans-membrane receptor (UTR) are up-regulated in the heart under pathological conditions. Previous in vitro studies have shown that UTII trans-activates the epidermal growth factor receptor (EGFR), however, the role of such novel signalling pathway stimulated by UTII is currently unknown. In this study, we hypothesized that EGFR trans-activation by UTII might exert a protective effect in the overloaded heart. To test this hypothesis, we induced cardiac hypertrophy by transverse aortic constriction (TAC) in wild-type mice, and tested the effects of the UTII antagonist Urantide (UR) on cardiac function, structure, and EGFR trans-activation. After 7 days of pressure overload, UR treatment induced a rapid and significant impairment of cardiac function compared to vehicle. In UR-treated TAC mice, cardiac dysfunction was associated with reduced phosphorylation levels of the EGFR and extracellular-regulated kinase (ERK), increased apoptotic cell death and fibrosis. In vitro UTR stimulation induced membrane translocation of ?-arrestin 1/2, EGFR phosphorylation/internalization, and ERK activation in HEK293 cells. Furthermore, UTII administration lowered apoptotic cell death induced by serum deprivation, as shown by reduced TUNEL/Annexin V staining and caspase 3 activation. Interestingly, UTII-mediated EGFR trans-activation could be prevented by UR treatment or knockdown of ?-arrestin 1/2. Our data show, for the first time in vivo, a new UTR signalling pathway which is mediated by EGFR trans-activation, dependent by ?-arrestin 1/2, promoting cell survival and cardioprotection.
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AngioJet rheolytic thrombectomy for acute superficial femoral artery stent or femoropopliteal by-pass thrombosis.
Monaldi Arch Chest Dis
PUBLISHED: 12-22-2010
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Thrombosis of superficial femoral artery (SFA) nitinol stents or polytetrafluoroethylene (PTFE) femoropopliteal bypass grafts after discontinuation of antiplatelet therapy is an emergent clinical challenge of acute limb ischemia (ALI), requiring immediate percutaneous intervention. Currently, there is no evidence-based approach for the management of such complications. We describe the cases of two patients presenting with ALI due to nitinol stent thrombosis after discontinuation of antiplatelet therapy and the case of a patient presenting with ALI due to PTFE femoropopliteal graft thrombosis in which limb salvage was obtained by AngioJet rheolytic thrombectomy and re-stenting. In both cases, the thrombus was successfully removed using the Possis AngioJet mechanical thrombectomy catheter and percutaneous transluminal angioplasty (PTA) was performed to recanalize two femoropopliteal nitinol stents and a femoropopliteal PTFE graft. In both cases, optimal angiographic result was obtained. To the best of our knowledge, these are the first three cases reporting the use of the AngioJet rheolytic thrombectomy in ALI due to stent or graft thrombosis. Taken together, these cases suggest that AngioJet rheolytic thrombectomy might represent a novel effective strategy in the percutaneous treatment of stent or graft thrombosis determining ALI.
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Development of a gas chromatographic/mass spectrometric method for determination of phthalates in oily foods.
J AOAC Int
PUBLISHED: 03-26-2010
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A GC/MS method was developed for simultaneous determination of 12 phthalates and four other plasticizers--acetyl tributyl citrate, di(2-ethylhexyl) adipate, dibutyl sebacate, di-isononyl cyclohexane 1,2-dicarboxylate (DINCH)--in vegetable oil, pesto, and tomato sauce. Samples were extracted with acetonitrile and cleaned on a Florisil column. The final extract was analyzed by GC in combination with ion trap MS. The phthalates and di-isononyl cyclohexane 1,2-dicarboxylate were detected by MS/MS, while the other three plasticizers were monitored in the same GC run using full scan mode. The analytical process was validated in each matrix by the analysis of blank samples. Performance characteristics, such as linearity, LOQ, precision, and recoveries were studied. Studies at fortification levels of 0.25-200 mg/kg gave mean recoveries ranging from 71 to 106% and RSD values between 7 and 12% for all compounds. LOQs were 0.050-0.10 mg/kg for all the target compounds except di-isononyl phthalate, di-isodecyl phthalate, and DINCH (2.0 mg/kg).
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Induction of mitogen-activated protein kinases is proportional to the amount of pressure overload.
Hypertension
PUBLISHED: 11-09-2009
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Pressure overload has been shown to induce mitogen activated protein kinases (MAPKs) and reactivate the atrial natriuretic factor in the heart. To test the sensitivity of these signals to pressure overload, we assayed the activity of MAPKs extracellular signal-regulated kinase, c-Jun N-terminal kinase 1, and p38 in protein lysates from the left ventricle (LV) or white blood cells (WBC) isolated from aortic banded mice with varying levels of pressure overload. In separated mice we measured atrial natriuretic factor mRNA levels by Northern blotting. As expected, a significant induction of atrial natriuretic factor mRNA levels was observed after aortic banding, and it significantly correlated with the trans-stenotic systolic pressure gradient but not with the LV weight:body weight ratio. In contrast, a significant correlation with systolic pressure gradient or LV weight:body weight ratio was observed for all of the MAPK activity detected in LV samples or WBCs. Importantly, LV activation of MAPKs significantly correlated with their activation in WBCs from the same animal. To test whether MAPK activation in WBCs might reflect uncontrolled blood pressure levels in humans, we assayed extracellular signal-regulated kinase, c-Jun N-terminal kinase 1, and p38 activation in WBCs isolated from normotensive volunteers, hypertensive patients with controlled blood pressure values, or hypertensive patients with uncontrolled blood pressure values. Interestingly, in hypertensive patients with controlled blood pressure values, LV mass and extracellular signal-regulated kinase phosphorylation were significantly reduced compared with those in hypertensive patients with uncontrolled blood pressure values. These results suggest that MAPKs are sensors of pressure overload and that extracellular signal-regulated kinase activation in WBCs might be used as a novel surrogate biomarker of uncontrolled human hypertension.
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Induction of adaptive response in human blood lymphocytes exposed to radiofrequency radiation.
Radiat. Res.
PUBLISHED: 07-08-2009
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The incidence of micronuclei was evaluated to assess the induction of an adaptive response to non-ionizing radiofrequency (RF) radiation in peripheral blood lymphocytes collected from five different human volunteers. After stimulation with phytohemagglutinin for 24 h, the cells were exposed to an adaptive dose of 900 MHz RF radiation used for mobile communications (at a peak specific absorption rate of 10 W/kg) for 20 h and then challenged with a single genotoxic dose of mitomycin C (100 ng/ml) at 48 h. Lymphocytes were collected at 72 h to examine the frequency of micronuclei in cytokinesis-blocked binucleated cells. Cells collected from four donors exhibited the induction of adaptive response (i.e., responders). Lymphocytes that were pre-exposed to 900 MHz RF radiation had a significantly decreased incidence of micronuclei induced by the challenge dose of mitomycin C compared to those that were not pre-exposed to 900 MHz RF radiation. These preliminary results suggested that the adaptive response can be induced in cells exposed to non-ionizing radiation. A similar phenomenon has been reported in cells as well as in animals exposed to ionizing radiation in several earlier studies. However, induction of adaptive response was not observed in the remaining donor (i.e., non-responder). The incidence of micronuclei induced by the challenge dose of mitomycin C was not significantly different between the cells that were pre-exposed and unexposed to 900 MHz RF radiation. Thus the overall data indicated the existence of heterogeneity in the induction of an adaptive response between individuals exposed to RF radiation and showed that the less time-consuming micronucleus assay can be used to determine whether an individual is a responder or non-responder.
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Reactive oxygen species formation is not enhanced by exposure to UMTS 1950 MHz radiation and co-exposure to ferrous ions in Jurkat cells.
Bioelectromagnetics
PUBLISHED: 05-29-2009
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This study was designed to assess if radiofrequency (RF) radiation induces oxidative stress in cultured mammalian cells when given alone or in combination with ferrous ions (FeSO(4)). For this purpose the production of reactive oxygen species (ROS) was measured by flow cytometry in human lymphoblastoid cells exposed to 1950 MHz signal used by the third generation wireless technology of the Universal Mobile Telecommunication System (UMTS) at Specific Absorption Rate of 0.5 and 2.0 W/kg. Short (5-60 min) or long (24 h) duration exposures were carried out in a waveguide system under strictly controlled conditions of both dosimetry and environment. Cell viability was also measured after 24 h RF exposure using the Resazurin and Neutral Red assays. Several co-exposure protocols were applied to test if RF radiation is able to alter ROS formation induced by FeSO(4) (RF given before or concurrently to FeSO(4)). The results obtained indicate that non-thermal RF exposures do not increase spontaneous ROS formation in any of the experimental conditions investigated. Consistent with the lack of ROS production, no change in cell viability was observed in Jurkat cells exposed to RF radiation for 24 h. Similar results were obtained when co-exposures were considered: combined exposures to RF radiation and FeSO(4) did not increase ROS formation induced by the chemical treatment alone. In contrast, in cultures treated with FeSO(4) as positive control, a dose-dependent increase in ROS formation was recorded, validating the sensitivity of the method employed.
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Endovascular treatment of lower extremity arteries is associated with an improved outcome in diabetic patients affected by intermittent claudication.
BMC Surg
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Lower extremity peripheral arterial disease (LE-PAD) is a highly prevalent condition among diabetic patients, associated with reduced walking capacity and a high incidence of cardiovascular events. Endovascular revascularization of lower extremities arteries improves walking performance and quality of life of diabetic patients affected by intermittent claudication, but few studies evaluated the impact of revascularization on cardiovascular outcome in this high-risk population. Accordingly, in the present study we evaluated if leg-ischemia resolution by effective lower limbs percutaneous revascularization can also impact cardiovascular outcome in a homogeneous group of diabetic patients affected by intermittent claudication.
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Ankle/brachial index to everyone.
BMC Surg
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In the last years significant attention has been paid in identifying markers of subclinical atherosclerosis or of increased cardiovascular risk.
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Abdominal aortic aneurysm in patients affected by intermittent claudication: prevalence and clinical predictors.
BMC Surg
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Abdominal aortic aneurysm (AAA) is a frequent cause of death among elderly. Patients affected by lower extremity peripheral arterial disease (LE-PAD) seem to be particularly at high risk for AAA. We aimed this study at assessing the prevalence and the clinical predictors of the presence of AAA in a homogeneous cohort of LE-PAD patients affected by intermittent claudication.
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Use of statins in lower extremity artery disease: a review.
BMC Surg
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Lower extremity artery disease (LE-PAD) is one of the most common manifestations of atherosclerosis, particularly in elderly patients, and it is related to a high cardiovascular risk.
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Effects of successful percutaneous lower extremity revascularization on cardiovascular outcome in patients with peripheral arterial disease.
Int. J. Cardiol.
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Lower extremity peripheral arterial disease (LE-PAD) reduces walking capacity and is associated with an increased cardiovascular risk. Endovascular revascularization of LE-PAD improves walking performance and quality of life. In the present study, we determined whether successful lower limbs revascularization also impacts cardiovascular outcome in LE-PAD patients.
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Induction of an adaptive response in human blood lymphocytes exposed to radiofrequency fields: influence of the universal mobile telecommunication system (UMTS) signal and the specific absorption rate.
Mutat. Res.
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The induction of an adaptive response (AR) was examined in human peripheral blood lymphocytes exposed to non-ionizing radiofrequency fields (RF). Cells from nine healthy human volunteers were stimulated for 24h with phytohaemagglutinin and then exposed for 20h to an adaptive dose (AD) of a 1950MHz RF UMTS (universal mobile telecommunication system) signal used for mobile communications, at different specific absorption rates (SAR) of 1.25, 0.6, 0.3, and 0.15W/kg. This was followed by treatment of the cells at 48h with a challenge dose (CD) of 100ng/ml mitomycin C (MMC). Lymphocytes were collected at the end of the 72h total culture period. The cytokinesis-block method was used to record the frequency of micronuclei (MN) as genotoxicity end-point. When lymphocytes from six donors were pre-exposed to RF at 0.3W/kg SAR and then treated with MMC, these cells showed a significant reduction in the frequency of MN, compared with the cells treated with MMC alone; this result is indicative of induction of AR. The results from our earlier study indicated that lymphocytes that were stimulated for 24h, exposed for 20h to a 900MHz RF GSM (global system for mobile communication) signal at 1.25W/kg SAR and then treated with 100ng/ml MMC, also exhibited AR. These overall data suggest that the induction of AR depends on RF frequency, type of the signal and SAR. Further characterization of RF-induced AR is in progress.
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Radiofrequency radiation at 1950 MHz (UMTS) does not affect key cellular endpoints in neuron-like PC12 cells.
Bioelectromagnetics
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In this study, rat pheochromocytoma (PC12) cells were exposed, as a model of neuron-like cells, to 1950 MHz radiofrequency (RF) radiation with a signal used by the 3G wireless technology of the Universal Mobile Telecommunications System (UMTS) to assess possible adverse effects. RF exposure for 24 h at a specific absorption rate (SAR) of 10 W/kg was carried out in a waveguide system under accurately controlled environmental and dosimetric parameters. DNA integrity, cell viability, and apoptosis were investigated as cellular endpoints relevant for carcinogenesis and other diseases of the central nervous system. Very sensitive biological assays were employed to assess the effects immediately after RF exposure and 24 h later, as demonstrated by the cellular response elicited in PC12 cells using positive control treatments provided for each assay. In our experimental conditions, 24 h of RF exposure at a carrier frequency and modulation scheme typical of a UMTS signal was not able to elicit any effect in the selected cellular endpoints in undifferentiated PC12 cells, despite the application of a higher SAR value than those applied in the majority of the studies reported in the literature.
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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.

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

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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.