Polymer-based or polymer-free stents in patients at high bleeding risk

BACKGROUND Polymer-free drug-coated stents provide superior clinical outcomes to bare-metal stents in patients at high bleeding risk who undergo percutaneous coronary intervention (PCI) and are treated with 1 month of dual antiplatelet therapy. Data on the use of polymer-based drug-eluting stents, as compared with polymer-free drug-coated stents, in such patients are limited. METHODS In an international, randomized, single-blind trial, we compared polymer-based zotarolimus-eluting stents with polymer-free umirolimus­coated stents in patients at high bleeding risk. After PCI, patients were treated with 1 month of dual antiplatelet therapy, followed by single antiplatelet therapy. The primary outcome was a safety composite of death from cardiac causes, myocardial infarction, or stent thrombosis at 1 year. The principal secondary outcome was target-lesion failure, an effectiveness composite of death from cardiac causes, target-vessel myocardial infarction, or clinically indicated target-lesion revascularization. Both outcomes were powered for noninferiority. RESULTS A total of 1996 patients at high bleeding risk were randomly assigned in a 1:1 ratio to receive zotarolimus-eluting stents (1003 patients) or polymer-free drugcoated stents (993 patients). At 1 year, the primary outcome was observed in 169 of 988 patients (17.1%) in the zotarolimus-eluting stent group and in 164 of 969 (16.9%) in the polymer-free drug-coated stent group (risk difference, 0.2 percentage points; upper boundary of the one-sided 97.5% confidence interval [CI], 3.5; noninferiority margin, 4.1; P=0.01 for noninferiority). The principal secondary outcome was observed in 174 patients (17.6%) in the zotarolimus-eluting stent group and in 169 (17.4%) in the polymer-free drug-coated stent group (risk difference, 0.2 percentage points; upper boundary of the one-sided 97.5% CI, 3.5; noninferiority margin, 4.4; P=0.007 for noninferiority). CONCLUSIONS Among patients at high bleeding risk who received 1 month of dual antiplatelet therapy after PCI, use of polymer-based zotarolimus-eluting stents was noninferior to use of polymer-free drug-coated stents with regard to safety and effectiveness composite outcomes. (Funded by Medtronic; ONYX ONE ClinicalTrials.gov number, NCT03344653.). (AU)

The inhibitory effect of oligodeoxynucleotides complementary to different fragments of tRNA structure on the enzymatic binding of Phe-tRNA to poly-U-programmed eukaryotic ribosomes.

The effect of several oligodeoxynucleotides complementary to the fragments of yellow lupin tRNA(Phe) was tested in the aminoacylation of tRNA(Phe) and in the binding of Phe-tRNA(Phe) to poly-U-programmed eukaryotic ribosomes. Oligonucleotides tested in the aminoacylation test did not give any inhibition. Monomers and dimers did not have any significant influence on the binding assay, either. A different percentage of inhibition of the binding of Phe-tRNA to ribosomes has been observed for oligonucleotides. Heptamer complementary to the anticodon loop gave 100% inhibition of the binding reaction. However, the oligonucleotides complementary to both the anticodon loop and stem and longer than the heptamer were much less effective inhibitors. A high inhibitory effect was also observed for trimers and for the decamer complementary to the D-loop and CCA-end.