This work presents a new route to suppress grain growth and tune the sensitivity and selectivity of nanocrystalline SnO2 fibers. Unloaded and Pd‐loaded SnO2 nanofiber mats are synthesized by ...electrospinning followed by hot‐pressing at 80 °C and calcination at 450 or 600 °C. The chemical composition and microstructure evolution as a function of Pd‐loading and calcination temperature are examined using EDS, XPS, XRD, SEM, and HRTEM. Highly porous fibrillar morphology with nanocrystalline fibers comprising SnO2 crystallites decorated with tiny PdO crystallites is observed. The grain size of the SnO2 crystallites in the layers that are calcined at 600 °C decreases with increasing Pd concentration from about 15 nm in the unloaded specimen to about 7 nm in the 40 mol% Pd‐loaded specimen, indicating that Pd‐loading could effectively suppress the SnO2 grain growth during the calcination step. The Pd‐loaded SnO2 sensors have 4 orders of magnitude higher resistivity and exhibit significantly enhanced sensitivity to H2 and lower sensitivity to NO2 compared to their unloaded counterparts. These observations are attributed to enhanced electron depletion at the surface of the PdO‐decorated SnO2 crystallites and catalytic effect of PdO in promoting the oxidation of H2 into H2O. These phenomena appear to have a much larger effect on the sensitivity of the Pd‐loaded sensors than the reduction in grain size.
The cover image shows a scanning electron microscopy image of nanocrystalline Pd‐loaded SnO2 gas sensors produced by electrospinning. SnO2 and PdO nanocrystallites are presented in yellow and orange, respectively, in the false‐color image of the fibers in front. On page 4258, Avner Rothschild, Il‐Doo Kim, and co‐workers demonstrate that Pd‐loading remarkably enhances the sensitivity to CO and reduces the sensitivity to NO2.
Abstract Background The optimal duration of dual antiplatelet therapy (DAPT) remains controversial in patients with acute coronary syndrome (ACS). We sought to compare outcomes after the implantation ...of zotarolimus-eluting stent (ZES) between patients with ACS who received clopidogrel-based DAPT for > 6 months and those treated for ≤ 6 months. Methods From a registry of patients treated with ZESs between October 2005 and January 2010, 1740 patients with ACS were selected for the present analysis. Landmark analyses were performed for ACS patients who were event-free at 6 months follow-up (n = 1674). The primary outcome was a major adverse cardiac and cerebrovascular event (MACCE), including all-cause death, myocardial infarction (MI), target vessel revascularization (TVR), stent thrombosis, or stroke. We also performed adjustments for the baseline characteristics of patients, using their propensity-score matching (n = 469 pairs). Results During a median follow-up of 22.5 months, the rate of MACCE was 6.4% in patients with DAPT > 6 months (n = 1140) and 4.7% in patients with DAPT ≤ 6 months (n = 534) (adjusted hazard ratio HR 1.05; 95% confidence interval CI 0.61–1.82; p = 0.86). After propensity-score matching, DAPT > 6 months was not found to be associated with a lower incidence of MACCE compared with DAPT ≤ 6 months (adjusted HR 0.80, 95% CI 0.44–1.45, p = 0.46). The rates of all-cause death or MI, TVR, stent thrombosis, and stroke also did not differ significantly between two groups. Conclusion DAPT for > 6 months do not seem to be associated with improved clinical outcomes in patients with ACS undergoing percutaneous coronary intervention (PCI) with ZES.
There is a paucity of data regarding the long-term clinical outcomes of first- versus second-generation drug-eluting stent (DES), especially when used to treat complex lesions such as bifurcation ...lesions.
The current study compares the efficacy and safety of first- versus second-generation DES at the 5-year follow-up in patients who underwent bifurcation percutaneous coronary intervention (PCI).
A total of 5,498 patients with a bifurcation lesion who underwent PCI were pooled at a single patient level from COBIS (Coronary Bifurcation Stenting) registries II and III. Five-year target lesion failure (TLF) (the composite of cardiac death, myocardial infarction MI, and target lesion revascularization TLR) and cardiac death or MI were compared between the use of first-generation DES (n = 2,436) and second-generation DES (n = 3,062) during PCI. Propensity score matching was performed to reduce selection bias.
After a 1:1 propensity score matching procedure was conducted, the cohort consisted of 1,702 matched pairs. Patients treated with second-generation DES had a significantly lower risk of TLF at 5 years than those treated with first-generation DES in both overall and propensity-matched populations (matched hazard ratio HRmatched: 0.576; 95% confidence interval CI: 0.456 to 0.727; p <0.001). There were no significant differences in risk of a composite of cardiac death or MI between the 2 groups (HRmatched: 0.782; 95% CI: 0.539 to 1.133, P = 0.193). However, among patients who required a 2-stent technique, use of the second-generation DES reduced cardiac death or MI (HRmatched:0.422; 95% CI: 0.209 to 0.851, P = 0.016). On the other hand, among patients who required a one-stent technique, the risk of a composite of cardiac death or MI was similar between the 2 groups (HRmatched: 1.046; 95% CI: 0.664 to 1.650, P = 0.845). There was a significant interaction between stent generation and treatment strategy for cardiac death or MI (interaction P = 0.029).
In patients treated with PCI for a bifurcation lesion, the use of second-generation DES was associated with a significantly reduced risk of 5-year TLF than the use of first-generation DES. (Korean Coronary Bifurcation Stenting Registry II NCT01642992; COBIS II) (Korean Coronary Bifurcation Stenting Registry III NCT03068494 COBIS III)
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Cerebral ischemia leads to brain injury via a complex series of pathophysiological events. Therefore, multidrug treatments or multitargeting drug treatments are attractive options in efficiently ...limiting brain damage. Here, we report a novel multifunctional compound oxopropanoyloxy benzoic acid (OBA-09), a simple ester of pyruvate and salicylic acid. This protective effect was manifested by recoveries from neurological and behavioral deficits. OBA-09 exhibited antioxidative effects in the postischemic brain, which was evidenced by remarkable reduction of lipid peroxidation and 4-hydroxy-2-nonenal staining in OBA-09-administered animals. Reactive oxygen species generation was markedly suppressed in primary cortical cultures under oxygen-glucose deprivation. More interestingly, OBA-09 was capable of scavenging hydroxyl radical in cell-free assays. High-performance liquid chromatography results demonstrated that OBA-09 was hydrolyzed to salicylic acid and pyruvate with t(1/2) = 43 min in serum and 4.2 h in brain parenchyma, indicating that antioxidative function of OBA-09 is executed by itself and also by salicylic acid after the hydrolysis. In addition to antioxidative function, OBA-09 exerts anti-excitotoxic and anti-Zn(2+)-toxic functions, which might be attributed to attenuation of ATP and nicotinamide adenine dinucleotide depletion and to the suppression of nuclear factor-κB activity induction. Together these results indicate that OBA-09 has a potent therapeutic potential as a multimodal neuroprotectant in the postischemic brain and these effects were conferred by OBA-09 itself and subsequently its hydrolyzed products.
Curcumin (CUR) is a hydrophobic polyphenol derived from the rhizome of Curcuma longa. CUR confers protection in various pathological conditions, including many brain-related diseases, such as ...cerebral ischemia, intracerebral hemorrhage, or Alzheimer's disease, and these effects have been attributed to its anti-inflammatory and anti-oxidative properties. In the present study, we found CUR induced the nuclear translocation of nuclear factor E2-related factor 2 (Nrf2) in microglia, brain macrophage, and thus upregulated genes downstream of antioxidant response element, such as heme oxygenase 1, NAD(P)H:quinone oxidoreductase 1, glutamate-cysteine ligase modifier subunit, and ferritin light chain, and simultaneously downregulated lipopolysaccharide-induced inducible nitric oxide synthase expression. We showed that the anti-inflammatory effect of CUR in microglia is connected with its anti-oxidative effect in that CUR promotes Nrf2-p300 binding at the expense of p65-p300 binding. Since CUR is a dietary spice that is eaten on a daily basis, it appears that CUR could be used therapeutically to induce anti-oxidative effect and simultaneously ameliorate inflammatory conditions via up-downregulation of related genes.
•Non-ST-segment elevation myocardial infarction (NSTEMI) patients with higher ischemic and bleeding risks often receive clopidogrel.•Potent P2Y12 blockers for NSTEMI reduced ischemic risk but ...increased bleeding risk.•Earlier percutaneous coronary intervention and radial artery access reduced the risk of bleeding in NSTEMI.•The optimal dual antiplatelet therapy regimen in Asian patients with NSTEMI needs to be determined.
Potent P2Y12 blockers are preferred in patients with acute non-ST-segment elevation myocardial infarction (NSTEMI) undergoing percutaneous coronary intervention (PCI). However, the risk of bleeding remains a major concern. We assessed the association of potent P2Y12 blockers with ischemic and bleeding outcomes in patients with NSTEMI.
From the Korea Acute Myocardial Infarction Registry-National Institute of Health database, 4927 patients with NSTEMI receiving drug-eluting stents (DES) were divided into potent P2Y12 blocker (ticagrelor or prasugrel, n=901) and clopidogrel (n=3180) groups. Propensity-matched 12-month ischemic and bleeding events were compared. Patients who received anticoagulants or who discontinued P2Y12 blockers or switched between potent P2Y12 blockers and clopidogrel were excluded.
In the overall population, patients at higher ischemic and bleeding risks more often received clopidogrel. After propensity matching (n=901 in each group), 12-month rates of major adverse cardiac and cerebrovascular events were lower (7.3% vs. 10.1%, p=0.038), but Thrombolysis in Myocardial Infarction (TIMI) major or minor bleeding rates were higher (5.9% vs. 2.2%, p<0.001) with potent P2Y12 blockers. Twelve-month rates of death from any cause, MI, stroke, or TIMI major bleeding were not different. On multivariate analysis, 12-month risk of TIMI major or minor bleeding was higher with B2 or C lesion, potent P2Y12 blocker use, body weight <60kg, and lower with time to PCI <12h and radial artery access.
In patients with NSTEMI receiving DES, potent P2Y12 blockers were associated with reduced ischemic but increased bleeding risk with similar net clinical benefits.
Objective We aimed to determine whether the extension of ablation could influence the ablation outcome for ventricular tachycardia (VT)/premature ventricular contractions (PVCs) from the right ...ventricular outflow tract (RVOT).
Methods and results The radiofrequency catheter ablation results of 33 VT/6 frequent PVCs from the RVOT were analysed. The ablation extension was divided into 3 categories from the final successful ablation point with the earliest activation: (I) focal ablation (15 cases); ablation at 1 or 2 points; (II) focal with extended ablation (12 cases); focal and surrounding area ablation (maximum ≤1 cm) after elimination of clinical VT/PVCs; and (III) broad ablation (12 cases); continued broad ablation (maximum >1 cm) after elimination of clinical VT/PVCs. Acute termination was defined as the complete elimination and non-inducibility of clinical VT/PVCs during the procedure. For the mean follow-up of 12.8 months, the recurrence rate was not significantly different among the groups (P = 0.49). The mean procedure time was longer in group II, but ablation times and complication rates were not different among the groups. When acute termination was achieved, the overall recurrence rate was 7.6%. However, when confirming absence of the clinical VT/PVCs using 24-hour Holter monitoring immediately after the procedure, the recurrence rate was 2.7%.
Conclusions Ablation extension did not affect ablation outcome of VT/PVCs from the RVOT. Confirmation of absence of clinical VT/PVCs using 24-hour Holter monitoring immediately after the procedure could guarantee long-term success.
Quaternary p‐type SrTi0.65Fe0.35O3–δ (STFO) nanofibers with diameters ranging from 70 to 500 nm were synthesized via electrospinning and subsequent calcination at 750 °C. The STFO fibers showed ...single perovskite structure and polycrystalline fiber morphologies composed of small nanocrystallites in the range of 10–12 nm. The semiconducting oxygen sensor using STFO fiber network exhibited a wide temperature‐independence of resistance (≈12 ± 4 kΩ) that exceeded the range of 600–950 °C, high oxygen response (${{R_{{\rm O}_{{\rm 2}} } } \mathord{\left/ {\vphantom {{R_{{\rm O}_{{\rm 2}} } } {R_{{\rm N}_{{\rm 2}} } }}} \right. \kern-\nulldelimiterspace} {R_{{\rm N}_{{\rm 2}} } }}$ = 4.08 at 20% O2), and a fast response time (t = 2.1 s at 20% O2) upon cyclic oxygen exposure. These superior properties were attributed to the high surface‐to‐volume ratio of STFO fiber network and the effective diffusion of oxygen gas onto highly porous STFO‐sensing layers.
Quaternary p‐type SrTi0.65Fe0.35O3– δ (STFO) nanofibers with polycrystalline structure are synthesized via electrospinning and used as high‐sensitivity oxygen‐sensing layers.
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