Mechanochemical Synthesis and Rapid Consolidation of Nanocrystalline 3NiAl- Al

Nanopowders of 3NiAl and Al2O3 were synthesized from 3NiO and 5Al powders by high-energy ball milling. Nanocrystalline Al2O3 reinforced composite was consolidated by high-frequency induction-heated sintering within 3 minutes from mechanochemically synthesized powders of Al2O3 and 3NiAl. The advantage of this process is that it allows very quick densification to near theoretical density and inhibition grain growth. Nanocrystalline materials have received much attention as advanced engineering materials with improved physical and mechanical properties. The relative density of the composite was 97%. The average Vickers hardness and fracture toughness values obtained were 804 kg/mm2 and 7.5 MPa⋅m1/2, respectively

Sirolimus- Versus Paclitaxel-Eluting Stents for the Treatment of Coronary Bifurcations Results From the COBIS (Coronary Bifurcation Stenting) Registry

ObjectivesWe aimed to compare the long-term clinical outcomes of patients treated with sirolimus-eluting stents (SES) or paclitaxel-eluting stents (PES) for coronary bifurcation lesions.BackgroundThere are limited data regarding comparisons of SES and PES for the treatment of bifurcation lesions.MethodsPatients who received percutaneous coronary intervention for non-left main bifurcation lesions were enrolled from 16 centers in Korea between January 2004 and June 2006. We compared major adverse cardiac events (MACE [cardiac death, myocardial infarction, or target lesion revascularization]) between the SES and PES groups in patients overall and in 407 patient pairs generated by propensity-score matching.ResultsWe evaluated 1,033 patients with bifurcation lesions treated with SES and 562 patients treated with PES. The median follow-up duration was 22 months. Treatment with SES was associated with a lower incidence of MACE (hazard ratio [HR]: 0.53, 95% confidence interval [CI]: 0.32 to 0.89, p < 0.01) and target lesion revascularization (HR: 0.55, 95% CI: 0.31 to 0.97, p = 0.02), but not of cardiac death (HR: 2.77, 95% CI: 0.40 to 18.99, p = 0.62) and cardiac death or myocardial infarction (HR: 0.97, 95% CI: 0.38 to 2.49, p = 0.94). After propensity-score matching, patients with SES still had fewer MACE and target lesion revascularization incidences than did patients with PES (HR: 0.52, 95% CI: 0.30 to 0.91, p = 0.02, and HR: 0.48, 95% CI: 0.25 to 0.91, p = 0.02, respectively). There was no significant difference in the occurrences of stent thrombosis between the groups (0.7% vs. 0.7%, p = 0.94).ConclusionsIn patients with bifurcation lesions, the use of SES resulted in better long-term outcomes than did the use of PES, primarily by decreasing the rate of repeat revascularization. (Coronary Bifurcation Stenting Registry in South Korea [COBIS]; NCT00851526

Drug-Eluting Stenting Followed by Cilostazol Treatment Reduces Late Restenosis in Patients With Diabetes Mellitus The DECLARE-DIABETES Trial (A Randomized Comparison of Triple Antiplatelet Therapy With Dual Antiplatelet Therapy After Drug-Eluting Stent Implantation in Diabetic Patients)

ObjectivesWe sought to evaluate the impact of cilostazol on neointimal hyperplasia after drug-eluting stent (DES) implantation in patients with diabetes mellitus (DM).BackgroundAlthough cilostazol has reduced the extent of neointimal hyperplasia and restenosis in patients after bare-metal stent implantation, it is not known whether this effect occurs after DES implantation in diabetic patients.MethodsThis randomized, multicenter, prospective study compared triple antiplatelet therapy (aspirin, clopidogrel, and cilostazol, triple group, n = 200) and dual antiplatelet therapy (aspirin and clopidogrel, standard group, n = 200) for 6 months in patients with DM receiving DES. The primary end point was in-stent late loss at 6 months.ResultsThe 2 groups had similar baseline clinical and angiographic characteristics. The in-stent (0.25 ± 0.53 mm vs. 0.38 ± 0.54 mm, p = 0.025) and in-segment (0.42 ± 0.50 mm vs. 0.53 ± 0.49 mm, p = 0.031) late loss were significantly lower in the triple versus standard group, as were 6-month in-segment restenosis (8.0% vs. 15.6%, p = 0.033) and 9-month target lesion revascularization (TLR) (2.5% vs. 7.0%, p = 0.034). At 9 months, major adverse cardiac events, including death, myocardial infarction, and TLR, tended to be lower in the triple than in the standard group (3.0% vs. 7.0%, p = 0.066). Multivariate analysis showed that sirolimus-eluting stents and the use of cilostazol were strong predictors of reduced restenosis or TLR.ConclusionsTriple antiplatelet therapy after DES implantation decreased angiographic restenosis and extent of late loss, resulting in a reduced risk of 9-month TLR compared with dual antiplatelet therapy in diabetic patients

Impact of the Metabolic Syndrome on the Clinical Outcome of Patients with Acute ST-Elevation Myocardial Infarction

We sought to determine the prevalence of metabolic syndrome (MS) in patients with acute myocardial infarction and its effect on clinical outcomes. Employing data from the Korea Acute Myocardial Infarction Registry, a total of 1,990 patients suffered from acute ST-elevation myocardial infarction (STEMI) between November 2005 and December 2006 were categorized according to the National Cholesterol Education Program-Adult Treatment Panel III criteria of MS. Primary study outcomes included major adverse cardiac events (MACE) during one-year follow-up. Patients were grouped based on existence of MS: group I: MS (n=1,182, 777 men, 62.8±12.3 yr); group II: Non-MS (n=808, 675 men, 64.2±13.1 yr). Group I showed lower left ventricular ejection fraction (LVEF) (P=0.005). There were no differences between two groups in the coronary angiographic findings except for multivessel involvement (P=0.01). The incidence of in-hospital death was higher in group I than in group II (P=0.047), but the rates of composite MACE during one-year clinical follow-up showed no significant differences. Multivariate analysis showed that low LVEF, old age, MS, low high density lipoprotein cholesterol and multivessel involvement were associated with high in-hospital death rate. In conclusion, MS is an important predictor for in-hospital death in patients with STEMI

Randomized Trial of Stents Versus Bypass Surgery for Left Main Coronary Artery Disease 5-Year Outcomes of the PRECOMBAT Study

AbstractBackgroundIn a previous randomized trial, we found that percutaneous coronary intervention (PCI) was not inferior to coronary artery bypass grafting (CABG) for the treatment of unprotected left main coronary artery stenosis at 1 year.ObjectivesThis study sought to determine the 5-year outcomes of PCI compared with CABG for the treatment of unprotected left main coronary artery stenosis.MethodsWe randomly assigned 600 patients with unprotected left main coronary artery stenosis to undergo PCI with a sirolimus-eluting stent (n = 300) or CABG (n = 300). The primary endpoint was a major adverse cardiac or cerebrovascular event (MACCE: a composite of death from any cause, myocardial infarction, stroke, or ischemia-driven target vessel revascularization) and compared on an intention-to-treat basis.ResultsAt 5 years, MACCE occurred in 52 patients in the PCI group and 42 patients in the CABG group (cumulative event rates of 17.5% and 14.3%, respectively; hazard ratio [HR]: 1.27; 95% confidence interval [CI]: 0.84 to 1.90; p = 0.26). The 2 groups did not differ significantly in terms of death from any cause, myocardial infarction, or stroke as well as their composite (8.4% and 9.6%; HR, 0.89; 95% CI, 0.52 to 1.52; p = 0.66). Ischemia-driven target vessel revascularization occurred more frequently in the PCI group than in the CABG group (11.4% and 5.5%, respectively; HR: 2.11; 95% CI: 1.16 to 3.84; p = 0.012).ConclusionsDuring 5 years of follow-up, our study did not show significant difference regarding the rate of MACCE between patients who underwent PCI with a sirolimus-eluting stent and those who underwent CABG. However, considering the limited power of our study, our results should be interpreted with caution. (Bypass Surgery Versus Angioplasty Using Sirolimus-Eluting Stent in Patients With Left Main Coronary Artery Disease [PRECOMBAT]; NCT00422968

Study design and rationale of 'Influence of Cilostazol-based triple anti-platelet therapy on ischemic complication after drug-eluting stent implantation (CILON-T)' study: A multicenter randomized trial evaluating the efficacy of Cilostazol on ischemic vascular complications after drug-eluting stent implantation for coronary heart disease

<p>Abstract</p> <p>Background</p> <p>Current guidelines recommend dual anti-platelet therapy, aspirin and clopidogrel, for patients treated with drug-eluting stent for coronary heart disease. In a few small trials, addition of cilostazol on dual anti-platelet therapy (triple anti-platelet therapy) showed better late luminal loss. In the real-world unselected patients with coronary heart disease, however, the effect of cilostazol on platelet reactivity and ischemic vascular events after drug-eluting stent implantation has not been tested. It is also controversial whether there is a significant interaction between lipophilic statin and clopidogrel.</p> <p>Methods/Design</p> <p>CILON-T trial was a prospective, randomized, open-label, multi-center, near-all-comer trial to demonstrate the superiority of triple anti-platelet therapy to dual anti-platelet therapy in reducing 6 months' major adverse cardiovascular/cerebrovascular events, composite of cardiac death, nonfatal myocardial infarction, target lesion revascularization and ischemic stroke. It also tested whether triple anti-platelet therapy is superior to dual anti-platelet therapy in inhibiting platelet reactivity in patients receiving percutaneous coronary intervention with drug-eluting stent. Total 960 patients were randomized to receive either dual anti-platelet therapy or triple anti-platelet therapy for 6 months and also, randomly stratified to either lipophilic statin (atorvastatin) or non-lipophilic statin (rosuvastatin) indefinitely. Secondary endpoints included all components of major adverse cardiovascular/cerebrovascular events, platelet reactivity as assessed by VerifyNow P2Y12 assay, effect of statin on major adverse cardiovascular/cerebrovascular events, bleeding complications, and albumin-to-creatinine ratio to test the nephroprotective effect of cilostazol. Major adverse cardiovascular/cerebrovascular events will also be checked at 1, 2, and 3 years to test the 'legacy' effect of triple anti-platelet therapy that was prescribed for only 6 months after percutaneous coronary intervention.</p> <p>Discussion</p> <p>CILON-T trial will give powerful insight into whether triple anti-platelet therapy is superior to dual anti-platelet therapy in reducing ischemic events and platelet reactivity in the real-world unselected patients treated with drug-eluting stent for coronary heart disease. Also, it will verify the laboratory and clinical significance of drug interaction between lipophilic statin and clopidogrel.</p> <p>Trial Registration</p> <p>National Institutes of Health Clinical Trials Registry (ClinicalTrials.gov identifier# NCT00776828).</p

Is it possible to reduce intra-hospital transport time for computed tomography evaluation in critically ill cases using the Easy Tube Arrange Device?

Objective Patients are often transported within the hospital, especially in cases of critical illness for which computed tomography (CT) is performed. Since increased transport time increases the risks of complications, reducing transport time is important for patient safety. This study aimed to evaluate the ability of our newly invented device, the Easy Tube Arrange Device (ETAD), to reduce transport time for CT evaluation in cases of critical illness. Methods This prospective randomized control study included 60 volunteers. Each participant arranged five or six intravenous fluid lines, monitoring lines (noninvasive blood pressure, electrocardiography, central venous pressure, arterial catheter), and therapeutic equipment (O2 supply device, Foley catheter) on a Resusci Anne mannequin. We measured transport time for the CT evaluation by using conventional and ETAD method. Results The median transport time for CT evaluation was 488.50 seconds (95% confidence interval [CI], 462.75 to 514.75) and, 503.50 seconds (95% CI, 489.50 to 526.75) with 5 and 6 fluid lines using the conventional method and 364.50 seconds (95% CI, 335.00 to 388.75), and 363.50 seconds (95% CI, 331.75 to 377.75) with ETAD (all P<0.001). The time differences were 131.50 (95% CI, 89.25 to 174.50) and 148.00 (95% CI, 116.00 to 177.75) (all P<0.001). Conclusion The transport time for CT evaluation was reduced using the ETAD, which would be expected to reduce the complications that may occur during transport in cases of critical illness

Visualizing Orbital Content of Electronic Bands in Anisotropic 2D Semiconducting ReSe2

Many properties of layered materials change as they are thinned from their bulk forms down to single layers, with examples including indirect-to-direct band gap transition in 2H semiconducting transition metal dichalcogenides as well as thickness-dependent changes in the valence band structure in post-transition metal monochalcogenides and black phosphorus. Here, we use angle-resolved photoemission spectroscopy to study the electronic band structure of monolayer ReSe$_{2}$, a semiconductor with a distorted 1T structure and in-plane anisotropy. By changing the polarization of incoming photons, we demonstrate that for ReSe$_{2}$, in contrast to the 2H materials, the out-of-plane transition metal $d_{z^{2}}$ and chalcogen $p_{z}$ orbitals do not contribute significantly to the top of the valence band which explains the reported weak changes in the electronic structure of this compound as a function of layer number. We estimate a band gap of 1.7 eV in pristine ReSe$_{2}$ using scanning tunneling spectroscopy and explore the implications on the gap following surface-doping with potassium. A lower bound of 1.4 eV is estimated for the gap in the fully doped case, suggesting that doping-dependent many-body effects significantly affect the electronic properties of ReSe$_{2}$. Our results, supported by density functional theory calculations, provide insight into the mechanisms behind polarization-dependent optical properties of rhenium dichalcogenides and highlight their place amongst two-dimensional crystals.Comment: 37 pages (including Supporting Information), 7 figures in the main tex