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Find video protocols related to scientific articles indexed in Pubmed.
Identifying Correlates of Success and Failure of Native Freshwater Fish Reintroductions.
Conserv. Biol.
PUBLISHED: 08-12-2014
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Reintroduction of imperiled native freshwater fish is becoming an increasingly important conservation tool amidst persistent anthropogenic pressures and new threats related to climate change. We summarized trends in native fish reintroductions in the current literature, identified predictors of reintroduction outcome, and devised recommendations for managers attempting future native fish reintroductions. We constructed random forest classifications using data from 260 published case studies of native fish reintroductions to estimate the effectiveness of variables in predicting reintroduction outcome. The outcome of each case was assigned as a success or failure on the basis of the author's perception of the outcome and on whether or not survival, spawning, or recruitment were documented during post-reintroduction monitoring. Inadequately addressing the initial cause of decline was the best predictor of reintroduction failure. Variables associated with habitat (e.g., water quality, prey availability) were also good predictors of reintroduction outcomes, followed by variables associated with stocking (e.g., genetic diversity of stock source, duration of stocking event). Consideration of these variables by managers during the planning process may increase the likelihood for successful outcomes in future reintroduction attempts of native freshwater fish. Identificación de Correlaciones de Éxito y Fracaso de Reintroducciones de Peces de Nativos Agua Dulce.
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Treatment and outcomes of ST segment elevation myocardial infarction and out-of-hospital cardiac arrest in a regionalized system of care based on presence or absence of initial shockable cardiac arrest rhythm.
Am. J. Cardiol.
PUBLISHED: 07-16-2014
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The aim of this study was to evaluate the treatment and outcomes of patients with ST-segment elevation myocardial infarctions complicated by out-of-hospital cardiac arrest in a regional system of care. In this retrospective study, the effect of the absence of an initial shockable arrest rhythm was analyzed. The primary end point of survival with good neurologic outcome in patients with and without an initial shockable arrest rhythm was adjusted for age, witnessed arrest, bystander cardiopulmonary resuscitation, and treatment with therapeutic hypothermia and percutaneous coronary intervention. One-hundred sixty-eight of 348 patients (49%) survived to hospital discharge. Patients with a shockable initial rhythm were more likely to receive therapeutic hypothermia (48% vs 37%, risk ratio 1.2, 95% confidence interval [CI] 1.0 to 1.5) and to be treated in the cardiac catheterization laboratory (80% vs 43%, risk ratio 2.8, 95% CI 2.0 to 3.8). The likelihood of survival with good neurologic outcome in patients with a shockable initial rhythm compared with those presenting without a shockable rhythm was 4.8 (95% CI 2.7 to 8.7). In patients who underwent percutaneous coronary intervention, the likelihood of survival with good neurologic outcome was higher (risk ratio 2.7, 95% CI 1.1 to 6.8) in those with a shockable rhythm. In conclusion, the absence of an initial shockable rhythm in patients with ST-segment elevation myocardial infarctions plus out-of-hospital cardiac arrest is associated with significantly worse survival and neurologic outcome. These differences persist despite application of therapies including therapeutic hypothermia and percutaneous coronary intervention within a regionalized system of care.
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Current state of ST-segment myocardial infarction: evidence-based therapies and optimal patient outcomes in advanced systems of care.
Cardiol Clin
PUBLISHED: 06-10-2014
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Advances in reperfusion therapy for ST-segment elevation myocardial infarction (STEMI) provide optimal patient outcomes. Reperfusion therapies, including contemporary primary percutaneous coronary intervention, represent decades of clinical evidence development in large clinical trials and national databases. However, rapid identification of STEMI and guideline-directed management of patients across broad populations have been best achieved in advanced systems of care. Current outcomes in STEMI reflect the evolution of both clinical data and idealized health care delivery networks.
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Draft Genome Sequence of Enterobacter cloacae Strain JD6301.
Genome Announc
PUBLISHED: 05-31-2014
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Enterobacter cloacae strain JD6301 was isolated from a mixed culture with wastewater collected from a municipal treatment facility and oleaginous microorganisms. A draft genome sequence of this organism indicates that it has a genome size of 4,772,910 bp, an average G+C content of 53%, and 4,509 protein-coding genes.
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AFib in special populations.
Am. J. Med.
PUBLISHED: 03-25-2014
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For physicians who see and treat patients who present with AFib in routine clinical practice there are 4 important factors to understand and bear in mind when diagnosing and planning treatment strategies: age, gender, prior or incident heart failure, and underlying coronary artery disease (CAD) and acute coronary syndrome (ACS). (online video available at: http://education.amjmed.com/video.php?event_id=445&stage_id=5&vcs=1). This review addresses the clinical characteristics of each of these presentations in order. For all patients with AFib, of either gender or any age, the greatest risk is failure to prescribe anticoagulation therapy, with currently only about half of these patients are being prescribed anticoagulation therapy, a percentage that is often much lower in the elderly, where only about 1 in 3 eligible patients receive anticoagulation. This highlights the most important clinical point for physicians: first, diagnose! This means ensuring the simple procedure of taking the pulse; if that is irregular, then record the ECG and look for AFib. After these 2 simple steps, physicians should be aware of the 2 most important risk scoring systems at present, CHADS2, which has been updated as the CHAD2DS2 vascular score (CHA2DS2-VASc); the latter takes gender into account and is a more sensitive scoring system for differentiating truly low-risk patients from those who may appear to be low risk, but actually are at significant risk. As discussed, while the 2012 ESC guidelines recommend a shift toward a greater emphasis on identifying patients who are truly low-risk (vs those who are only apparently low risk), the US emphasis is on identifying the high-risk patients, and how use of the CHADS2 versus CHA2DS2-VASc to accomplish these 2 goals is outlined. Two further important subpopulations of AFib patients are those with congestive heart failure (CHF) and those with acute coronary syndromes (ACS). As discussed, the real progress that has been seen in the prognosis of CHF has not been seen for patients with CHF and concomitant AFib, meaning that even with optimal therapy, the patient with AFib who develops CHF is at higher risk of mortality. The challenge for patients with ACS and AFib is that their ACS will probably require antiplatelet therapy, and addition of anticoagulation therapy as prophylaxis against stroke and systemic embolism because of the AFib creates the problem of so-called "triple therapy." This review includes a clinical decision algorithm for balancing the lowest risk of thromboembolic events against the highest risk of bleeding in patients who must receive triple therapy. Finally, this review concludes with a brief overview of the possible benefits of the NOACs in these populations, while also emphasizing that all clinicians-especially primary care physicians, who may become the principal caregivers for these patients with AFib in the era of NOACs-should be familiar with one of current bleeding scores, perhaps the best of which is the HAS-BLED score, which includes patients who have hypertension, abnormal renal or liver function, bleeding history, predisposition or labile INR, elderly patients who are frail or >65 years, or with a history of drugs/alcohol concomitantly.
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Survival and neurologic outcome after out-of-hospital cardiac arrest: results one year after regionalization of post-cardiac arrest care in a large metropolitan area.
Prehosp Emerg Care
PUBLISHED: 01-08-2014
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Post-resuscitation care of cardiac arrest patients at specialized centers may improve outcome after out-of-hospital cardiac arrest (OOHCA). This study describes experience with regionalized care of resuscitated patients.
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Predictors of reperfusion delay in patients with ST elevation myocardial infarction self-transported to the hospital (from the American Heart Association's Mission: Lifeline Program).
Am. J. Cardiol.
PUBLISHED: 01-08-2014
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Primary percutaneous coronary intervention for ST elevation myocardial infarction (STEMI) is beneficial if performed in a timely manner. Self-transport patients with STEMI have prolonged treatment times compared with Emergency Medical Services-transported patients. This study evaluated self-transport patients with STEMI undergoing primary percutaneous coronary intervention to identify factors associated with prolonged door-to-balloon (D2B) times. From January 2007 to March 2011, data for 13,379 self-transport patients with STEMI treated at 432 hospitals in the Acute Coronary Treatment Intervention Outcomes Network Registry-Get With The Guidelines Registry were evaluated. Patients with a D2B time >90 minutes were compared with those with D2B time ?90 minutes. Factors associated with prolonged D2B (>90 minutes) were explored using logistic generalized estimating equations. The median (twenty-fifth, seventy-fifth percentiles) D2B time for the entire cohort was 72 minutes (58, 86), and 19% had a D2B time of >90 minutes. Over the study period, there was a significant increase in the percentage of patients achieving D2B time ?90 minutes. There were significant baseline differences between patients with D2B time ? versus >90 minutes. The main factors associated with prolonged treatment time were off-hour presentation (weekends and 7 p.m. to 7 a.m. weekdays), not obtaining an electrocardiogram within 10 minutes of hospital arrival, previous coronary artery bypass surgery, black race, older age, and female gender. In conclusion, although prolonged delay from arrival to electrocardiographic acquisition is a modifiable factor contributing to prolonged D2B times among self-transport patients with STEMI, additional factors (age, race, and gender) indicate that historic disparities for cardiovascular care still persist in terms of contemporary metrics for STEMI reperfusion.
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Effect of cangrelor on periprocedural outcomes in percutaneous coronary interventions: a pooled analysis of patient-level data.
Lancet
PUBLISHED: 09-03-2013
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Cangrelor is a potent, rapid-acting, reversible intravenous platelet inhibitor that was tested for percutaneous coronary intervention (PCI) in three large, double-blind, randomised trials. We did a pooled analysis of data from three trials that assessed the effectiveness of cangrelor against either clopidogrel or placebo in PCI.
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Emergency department bypass for ST-Segment-elevation myocardial infarction patients identified with a prehospital electrocardiogram: a report from the American Heart Association Mission: Lifeline program.
Circulation
PUBLISHED: 06-20-2013
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For patients identified before hospital arrival with ST-segment-elevation myocardial infarction, bypassing the emergency department (ED) with direct transport to the catheterization laboratory may shorten reperfusion times.
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Atomistic simulations of highly conductive molecular transport junctions under realistic conditions.
Nanoscale
PUBLISHED: 04-03-2013
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We report state-of-the-art atomistic simulations combined with high-fidelity conductance calculations to probe structure-conductance relationships in Au-benzenedithiolate (BDT)-Au junctions under elongation. Our results demonstrate that large increases in conductance are associated with the formation of monatomic chains (MACs) of Au atoms directly connected to BDT. An analysis of the electronic structure of the simulated junctions reveals that enhancement in the s-like states in Au MACs causes the increases in conductance. Other structures also result in increased conductance but are too short-lived to be detected in experiment, while MACs remain stable for long simulation times. Examinations of thermally evolved junctions with and without MACs show negligible overlap between conductance histograms, indicating that the increase in conductance is related to this unique structural change and not thermal fluctuation. These results, which provide an excellent explanation for a recently observed anomalous experimental result [Bruot et al., Nat. Nanotechnol., 2012, 7, 35-40], should aid in the development of mechanically responsive molecular electronic devices.
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Previous myocardial infarction as a risk factor for in-hospital cardiovascular outcomes (from the National Registry of Myocardial Infarction 4 and 5).
Am. J. Cardiol.
PUBLISHED: 02-07-2013
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Patients with acute coronary syndromes have a substantial disease burden and are at continued risk of future cardiovascular events. In this setting, the relation between previous myocardial infarction (MI) and the risk of subsequent in-hospital adverse cardiovascular outcomes has not been definitively established. The data were analyzed from 427,778 hospitalized patients presenting with acute MI from July 2002 to December 2006, who were enrolled in the National Registry of Myocardial Infarction 4-5 study. Multivariate logistic regression models were developed to examine the association between a history of MI and in-hospital all-cause mortality, recurrent MI, and congestive heart failure/pulmonary edema. Covariate adjustments were made for demographic characteristics, co-morbidities, prearrival medications, and health status at presentation. Similarly, multivariate linear regression models were used to evaluate the length of stay. Of the 232,927 patients with acute MI included in the present study after exclusions, 24.7% reported a history of MI. In-hospital mortality was not significantly different between the patients with and without a history of MI (adjusted odds ratio 0.99, 95% confidence interval 0.95 to 1.04, p = 0.75). However, patients with a previous MI had a small increased risk of in-hospital recurrent MI (adjusted odds ratio 1.18, 95% confidence interval 1.08 to 1.29, p <0.001) and congestive heart failure/pulmonary edema (adjusted odds ratio 1.23, 95% confidence interval1.19 to 1.28, p <0.001) compared with patients with no history of MI. In conclusion, a history of MI did not significantly affect in-hospital mortality after admission for an acute MI.
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Effect of different C/N ratios on carotenoid and lipid production by Rhodotorula glutinis.
Appl. Microbiol. Biotechnol.
PUBLISHED: 01-22-2013
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Due to the increasing demand for sustainable biofuels, microbial oils as feedstock for the transesterification into biodiesel have gained scientific and commercial interest. Also, microbial carotenoids have a considerable market potential as natural colorants. The carbon to nitrogen (C/N) ratio of the respective cultivation media is one of the most important parameters that influence the production of microbial lipids and carotenoids. Thus, in the present experiment, the influence of different C/N ratios, initial glucose loadings, and ammonium concentrations of the cultivation medium on microbial cell growth and lipid and carotenoid production by the oleaginous red yeast Rhodotorula glutinis has been assessed. As a general trend, both lipid and carotenoid production increased at high C/N ratios. It was shown that not only the final C/N ratio but also the respectively applied initial carbon and nitrogen contents influenced the observed parameters. The lipid yield was not affected by different ammonium contents, while the carotenoid production significantly decreased both at low and high levels of ammonium supply. A glucose-based increase from C/N 70 to 120 did not lead to an increased lipid production, while carotenoid synthesis was positively affected. Generally, it can be asserted that lipid and carotenoid synthesis are stimulated at higher C/N ratios.
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Number of coronary heart disease risk factors and mortality in patients with first myocardial infarction.
JAMA
PUBLISHED: 11-18-2011
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Few studies have examined the association between the number of coronary heart disease risk factors and outcomes of acute myocardial infarction in community practice.
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Role of polytetrahedral structures in the elongation and rupture of gold nanowires.
ACS Nano
PUBLISHED: 11-04-2011
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We report comprehensive high-accuracy molecular dynamics simulations using the ReaxFF force field to explore the structural changes that occur as Au nanowires are elongated, establishing trends as a function of both temperature and nanowire diameter. Our simulations and subsequent quantitative structural analysis reveal that polytetrahedral structures (e.g., icosahedra) form within the "amorphous" neck regions, most prominently for systems with small diameter at high temperature. We demonstrate that the formation of polytetrahedra diminishes the conductance quantization as compared to systems without this structural motif. We demonstrate that use of the ReaxFF force field, fitted to high-accuracy first-principles calculations of Au, combines the accuracy of quantum calculations with the speed of semiempirical methods.
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Comparison of clinical characteristics, treatments and outcomes of patients with ST-elevation acute myocardial infarction with versus without new or presumed new left bundle branch block (from NCDR®).
Am. J. Cardiol.
PUBLISHED: 07-05-2011
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Guidelines recommend urgent reperfusion for patients with new left bundle branch block (LBBB), similar to patients with ST-segment elevation myocardial infarction (STEMI). However, there are limited contemporary data comparing these 2 groups of patients. Patients presenting with acute STEMI or presumed new LBBB (nLBBB) enrolled in the Acute Coronary Treatment and Intervention Outcomes Network (ACTION) Registry-Get With the Guidelines (GWTG) from January 2007 to March 2009 were evaluated for clinical characteristics, treatment patterns, and outcomes. Logistic generalized estimating equation modeling was used to examine associated risk-adjusted mortality. Of 46,006 patients with either STEMI or nLBBB, 44,405 (96.5%) had STEMI, and 1,601 (3.5%) had nLBBB. Overall, patients with nLBBB had more baseline co-morbidities compared to those with STEMI. Compared to patients with STEMI, those with nLBBB were less likely to receive acute reperfusion (93.9% vs 48.3% p <0.0001) and were less likely to have door-to-balloon times ?90 minutes (76.8% vs 34.5%, p <0.0001). Mortality rates were higher for patients with nLBBB compared to those with STEMI (13.3% vs 5.6%, p <0.0001). After multivariate adjustment, nLBBB was not associated with an increased risk for in-hospital mortality (odds ratio 0.91, 95% confidence interval 0.75 to 1.12, p = 0.38). In conclusion, patients with nLBBB were clinically different from those with STEMI, with significantly more co-morbidities, and were less likely to receive emergent reperfusion therapy. Despite these differences, adjusted mortality rates were similar between patients with nLBBB and those with STEMI.
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Time-dependent density functional study of field emission from nanotubes composed of C, BN, SiC, Si, and GaN.
Nanotechnology
PUBLISHED: 06-06-2011
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Field emission from various types of nanotubes is studied by propagating the electronic density in real space and time using time-dependent density functional theory. Capped (5, 5) C, BN, SiC, Si, and GaN nanotubes are considered. The GaN, SiC, and Si nanotubes were found to be significantly better field emitters than C and BN nanotubes, both in terms of current magnitude and sharpness of peaks in the energy spectra. By analyzing the electronic structure of the various systems it is seen that the nanotubes with the highest currents have electron densities that extend significantly from the nanotube in the emission direction.
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Mortality incidence of patients with non-obstructive coronary artery disease diagnosed by computed tomography angiography.
Am. J. Cardiol.
PUBLISHED: 02-09-2011
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It was previously reported that event-free survival rates of symptomatic patients with coronary artery disease (CAD) diagnosed by computed tomographic angiography decreased incrementally from normal coronary arteries to obstructive CAD. The aim of this study was to investigate the clinical outcomes of symptomatic patients with nonobstructive CAD with luminal stenoses of 1% to 49% on the basis of coronary plaque morphology in an outpatient setting. Among 3,499 consecutive symptomatic subjects who underwent computed tomographic angiography, 1,102 subjects with nonobstructive CAD (mean age 59 ± 14 years, 69.9% men) were prospectively followed for a mean of 78 ± 12 months. Coronary plaques were defined as noncalcified, mixed, and calcified per patient. Multivariate Cox proportional-hazards models were developed to predict all-cause mortality. The death rate of patients with nonobstructive CAD was 3.1% (34 deaths). The death rate increased incrementally from calcified plaque (1.4%) to mixed plaque (3.3%) to noncalcified plaque (9.6%), as well as from single- to triple-vessel disease (p <0.001). In subjects with mixed or calcified plaques, the death rate increased with the severity of coronary artery calcium from 1 to 9 to ? 400. The risk-adjusted hazard ratios of all-cause mortality in patients with nonobstructive CAD were 3.2 (95% confidence interval 1.3 to 8.0, p = 0.001) for mixed plaques and 7.4 (95% confidence interval 2.7 to 20.1, p = 0.0001) for noncalcified plaques compared with calcified plaques. The areas under the receiver-operating characteristic curve to predict all-cause mortality were 0.75 for mixed and 0.86 for noncalcified coronary lesions. In conclusion, this study demonstrates that the presence of noncalcified and mixed coronary plaques provided incremental value in predicting all-cause mortality in symptomatic subjects with nonobstructive CAD independent of age, gender, and conventional risk factors.
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"Call 911" STEMI protocol to reduce delays in transfer of patients from non primary percutaneous coronary intervention referral Centers.
Crit Pathw Cardiol
PUBLISHED: 08-31-2010
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Primary percutaneous coronary intervention (PPCI) is the preferred method of reperfusion for ST-segment elevation myocardial infarction (STEMI), if it can be performed in a timely manner by an experienced interventional cardiologist at a high volume STEMI Receiving Center. However, an estimated 50% of STEMI patients present to STEMI Referral Centers without PPCI capability. Transfer of STEMI patients for PPCI has been shown to improve outcomes as compared with fibrinolysis given at the presenting hospital. Nonetheless, transfer of STEMI patients for PPCI has not been used extensively in the United States and is associated with markedly prolonged transfer times. This study demonstrates that rapid transfer of STEMI patients from community hospitals without PPCI capability to a STEMI Receiving Center is both safe and feasible using a standardized protocol with an integrated transfer system.
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Impact of chronic renal insufficiency on clinical outcomes in patients undergoing saphenous vein graft intervention with drug-eluting stents: a multicenter Southern Californian Registry.
Catheter Cardiovasc Interv
PUBLISHED: 07-13-2010
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To evaluate the clinical outcomes in patients with chronic renal insufficiency (CRI) who undergo saphenous vein graft (SVG) intervention with drug-eluting stents (DES).
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Appropriate cardiac cath lab activation: optimizing electrocardiogram interpretation and clinical decision-making for acute ST-elevation myocardial infarction.
Am. Heart J.
PUBLISHED: 03-29-2010
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During the last few decades, acute ST-elevation on an electrocardiogram (ECG) in the proper clinical context has been a reliable surrogate marker of acute coronary occlusion requiring primary percutaneous coronary intervention (PPCI). In 2004, the American College of Cardiology/American Heart Association ST-elevation myocardial infarction (STEMI) guidelines specified ECG criteria that warrant immediate angiography in patients who are candidates for primary PPCI, but new findings have emerged that suggest a reappraisal is warranted. Furthermore, as part of integrated and efficient STEMI systems, emergency department and emergency medical services providers are now encouraged to routinely make the time-sensitive diagnosis of STEMI and promptly activate the cardiac catheterization laboratory (Cath Lab) team. Our primary objective is to provide a practical summary of updated ECG criteria for emergency coronary angiography with planned PPCI, thus allowing clinicians to maximize the rate of appropriate Cath Lab activation and minimize the rate of inappropriate Cath Lab activation. We review the evidence for ECG interpretation strategies that either increase diagnostic specificity for "classic" STEMI and left bundle-branch block or improve diagnostic sensitivity in identifying 4 STEMI-equivalents: posterior MI, acute left main occlusion, de Winter ST/T-wave complex, and certain scenarios of resuscitated cardiac arrest.
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Comparison of sirolimus-eluting stents with paclitaxel-eluting stents in saphenous vein graft intervention (from a multicenter Southern California Registry).
Am. J. Cardiol.
PUBLISHED: 01-26-2010
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This study was designed to compare the safety and efficacy of sirolimus-eluting stents (SESs) to paclitaxel-eluting stents (PESs) in percutaneous intervention of saphenous vein graft (SVG) lesions. SVGs develop atherosclerosis at high rates and often require repeat revascularization. Percutaneous intervention with drug-eluting stents has become the preferred method of revascularization due to higher restenosis with bare metal stents and increased morbidity and mortality with repeat coronary artery bypass grafting. We sought to compare the rate of major adverse cardiac events and stent thrombosis between SESs and PESs in patients undergoing SVG intervention. A multicenter analysis of 172 patients with SVG lesions treated with SESs or PESs was performed. The 30-day and 1-year clinical outcomes of 102 patients receiving SESs were compared to those of 70 patients receiving PESs. There was no significant difference in baseline demographic, angiographic, and procedural characteristics between the SES and PES treatment groups. There was no statistical difference in major adverse cardiac events at 30 days and at 1 year (hazard ratio [HR] 1.58, 95% confidence interval [CI] 0.77 to 3.23, log-rank p = 0.21). There was also no difference in survival (HR 1.28, 95% CI 0.39 to 4.25, log-rank p = 0.69) or target vessel revascularization (HR 2.54, 95% CI 0.84 to 7.72, log-rank p = 0.09). In conclusion, this multicenter analysis of real-world patients demonstrated that SESs and PESs have similar clinical outcomes when used in SVG intervention.
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Choice of reperfusion strategy at hospitals with primary percutaneous coronary intervention: a National Registry of Myocardial Infarction analysis.
Circulation
PUBLISHED: 11-30-2009
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Many hospitals with percutaneous coronary intervention (PCI) capability also use fibrinolytic therapy in patients with ST-segment elevation myocardial infarction, but factors influencing the choice of reperfusion strategy at these hospitals are poorly understood. We examined clinical and system-related factors associated with choice of reperfusion strategy in patients with ST-segment elevation myocardial infarction at PCI-capable hospitals.
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Platelet inhibition with cangrelor in patients undergoing PCI.
N. Engl. J. Med.
PUBLISHED: 11-15-2009
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Cangrelor, a nonthienopyridine adenosine triphosphate analogue, is an intravenous blocker of the adenosine diphosphate receptor P2Y(12). This agent might have a role in the treatment of patients who require rapid, predictable, and profound but reversible platelet inhibition.
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Trends in the use of lipid-lowering medications at discharge in patients with acute myocardial infarction: 1998 to 2006.
Am. Heart J.
PUBLISHED: 01-23-2009
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Compelling evidence demonstrates that certain lipid-lowering medications improve outcomes after acute myocardial infarction (AMI), but to what extent national utilization has increased in response to trials and guidelines has not been well studied. The objective of this study is to determine trends in the use of lipid-lowering medications at discharge for AMI.
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Atherosclerotic risk factors and their association with hospital mortality among patients with first myocardial infarction (from the National Registry of Myocardial Infarction).
Am. J. Cardiol.
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Few studies have examined associations between atherosclerotic risk factors and short-term mortality after first myocardial infarction (MI). Histories of 5 traditional atherosclerotic risk factors at presentation (diabetes, hypertension, smoking, dyslipidemia, and family history of premature heart disease) and hospital mortality were examined among 542,008 patients with first MIs in the National Registry of Myocardial Infarction (1994 to 2006). On initial MI presentation, history of hypertension (52.3%) was most common, followed by smoking (31.3%). The least common risk factor was diabetes (22.4%). Crude mortality was highest in patients with MI with diabetes (11.9%) and hypertension (9.8%) and lowest in those with smoking histories (5.4%) and dyslipidemia (4.6%). The inclusion of 5 atherosclerotic risk factors in a stepwise multivariate model contributed little toward predicting hospital mortality over age alone (C-statistic = 0.73 and 0.71, respectively). After extensive multivariate adjustments for clinical and sociodemographic factors, patients with MI with diabetes had higher odds of dying (odds ratio [OR] 1.23, 95% confidence interval [CI] 1.20 to 1.26) than those without diabetes and similarly for hypertension (OR 1.08, 95% CI 1.06 to 1.11). Conversely, family history (OR 0.71, 95% CI 0.69 to 0.73), dyslipidemia (OR 0.62, 95% CI 0.60 to 0.64), and smoking (OR 0.85, 95% CI 0.83 to 0.88) were associated with decreased mortality (C-statistic = 0.82 for the full model). In conclusion, in the setting of acute MI, histories of diabetes and hypertension are associated with higher hospital mortality, but the inclusion of atherosclerotic risk factors in models of hospital mortality does not improve predictive ability beyond other major clinical and sociodemographic characteristics.
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Pharmacodynamic effects of cangrelor and clopidogrel: the platelet function substudy from the cangrelor versus standard therapy to achieve optimal management of platelet inhibition (CHAMPION) trials.
J. Thromb. Thrombolysis
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Cangrelor is an intravenous antagonist of the P2Y(12) receptor characterized by rapid, potent, predictable, and reversible platelet inhibition. However, cangrelor was not superior to clopidogrel in reducing the incidence of ischemic events in the cangrelor versus standard therapy to achieve optimal management of platelet inhibition (CHAMPION) trials. A prospectively designed platelet function substudy was performed in a selected cohort of patients to provide insight into the pharmacodynamic effects of cangrelor, particularly in regard to whether cangrelor therapy may interfere with the inhibitory effects of clopidogrel. This pre-defined substudy was conducted in a subset of patients from the CHAMPION-PCI trial (n = 230) comparing cangrelor with 600 mg of clopidogrel administered before percutaneous coronary intervention (PCI) and from the CHAMPION-PLATFORM trial (n = 4) comparing cangrelor at the time of PCI and 600 mg clopidogrel given after the PCI. Pharmacodynamic measures included P2Y12 reaction units (PRU) assessed by VerifyNow P2Y12 testing (primary endpoint marker), platelet aggregation by light transmittance aggregometry following 5 and 20 ?mol/L adenosine diphosphate stimuli, and markers of platelet activation determined by flow cytometry. The primary endpoint was the percentage of patients who achieved <20 % change in PRU between baseline and >10 h after PCI. The main trial was stopped early limiting enrollment in the platelet substudy. A total of 167 patients had valid pharmacodynamic assessments for the primary endpoint. The percent of individuals achieving <20 % change in PRU between baseline and >10 h after PCI was higher with cangrelor + clopidogrel (32/84, 38.1 %) compared with placebo + clopidogrel (21/83, 25.3 %), but this was not statistically significant (difference:12.79 %, 95 % CI: -1.18 %, 26.77 %;p = 0.076). All pharmacodynamic markers as well as the prevalence of patients with high on-treatment platelet reactivity were significantly lower in patients treated with cangrelor. A rapid platelet inhibitory effect was achieved during cangrelor infusion and a rapid offset of action after treatment discontinuation. This CHAMPION platelet function substudy represents the largest pharmacodynamic experience with cangrelor, demonstrating its potent P2Y(12) receptor inhibitory effects, and rapid onset/offset of action. Although there was no significant pharmacodynamic interaction when transitioning to clopidogrel therapy, further studies are warranted given that enrollment in this study was limited due to premature interruption of the main trial.
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Therapeutic hypothermia for acute myocardial infarction and cardiac arrest.
Am. J. Cardiol.
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This report focuses on cardioprotection and describes the advantages and disadvantages of various methods of inducing therapeutic hypothermia (TH) with regard to neuroprotection and cardioprotection for patients with cardiac arrest and ST-segment elevation myocardial infarction (STEMI). TH is recommended in cardiac arrest guidelines. For patients resuscitated after out-of-hospital cardiac arrest, improvements in survival and neurologic outcomes were observed with relatively slow induction of TH. More rapid induction of TH in patients with cardiac arrest might have a mild to modest incremental impact on neurologic outcomes. TH drastically reduces infarct size in animal models, but achievement of target temperature before reperfusion is essential. Rapid initiation of TH in patients with STEMI is challenging but attainable, and marked infarct size reductions are possible. To induce TH, a variety of devices have recently been developed that require additional study. Of particular interest is transcoronary induction of TH using a catheter or wire lumen, which enables hypothermic reperfusion in the absence of total-body hypothermia. At present, the main methods of inducing and maintaining TH are surface cooling, endovascular heat-exchange catheters, and intravenous infusion of cold fluids. Surface cooling or endovascular catheters may be sufficient for induction of TH in patients resuscitated after out-of-hospital cardiac arrest. For patients with STEMI, intravenous infusion of cold fluids achieves target temperature very rapidly but might worsen left ventricular function. More widespread use of TH would improve survival and quality of life for patients with out-of-hospital cardiac arrest; larger studies with more rapid induction of TH are needed in the STEMI population.
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Large-scale atomistic simulations of environmental effects on the formation and properties of molecular junctions.
ACS Nano
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Using an updated simulation tool, we examine molecular junctions composed of benzene-1,4-dithiolate bonded between gold nanotips, focusing on the importance of environmental factors and interelectrode distance on the formation and structure of bridged molecules. We investigate the complex relationship between monolayer density and tip separation, finding that the formation of multimolecule junctions is favored at low monolayer density, while single-molecule junctions are favored at high density. We demonstrate that tip geometry and monolayer interactions, two factors that are often neglected in simulation, affect the bonding geometry and tilt angle of bridged molecules. We further show that the structures of bridged molecules at 298 and 77 K are similar.
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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.

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.