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The enhanced stability of Co nanocrystals (NCs) when they are highly ordered at both nanometer and micrometer scales is reported. For the first time, it is shown that both the crystalline structure of Co nanoparticles (NPs) and their 2D hexagonal organization have a significant impact on the oxidation process rate enabling to produce various types of nanostructures including core-shell NPs. The Co core can be either polycrystalline or hexagonal close-packed (hcp) single-crystalline, whereas the oxide shell is composed either of CoO or of the spinel structrure Co3O4. The present results are evidenced through a careful high-resolution transmission electron microscopy (HRTEM) study and are highly reproducible. [ABSTRACT FROM AUTHOR]

A cobalt cementation process in ethanol–watersolvent atdifferent temperatures is presented. A new model is proposed whichtakes into account the depletion of the less electropositive metalby a shrinking core technique. The model comprises a system of twoordinary differential equations whose dependent variables are theconcentration of the cation undergoing cementation and the radiusof the sacrificial metal particles. An analytic solution is obtainedand a comparison between the present model and the traditional oneis proposed. The model is validated by experimental data regressionto investigate the cementation kinetics at different temperatures,and the relevant activation energy suggests the onset of a chemicalcontrol regime for all experimental runs. Finally, the cemented phaseis morphologically and chemically characterized, and the size distributionof the relevant metal aggregates is determined by means of both dynamiclight scattering in solution and atomic force microscopy after dropcasting onto a solid substrate. [ABSTRACT FROM AUTHOR]

Abstract: In patients on oral anticoagulant (OAC) therapy undergoing percutaneous coronary intervention (PCI) with stent, international guidelines endorse the use of direct oral anticoagulants (DOAC) rather than vitamin K antagonists (VKA) and dual antithrombotic therapy (DAT) rather than triple antithrombotic therapy (TAT). The aim of this study was to evaluate contemporary real-world data on antithrombotic regimens and outcome in patients on OAC undergoing PCI with stent. Consecutive patients on OAC undergoing PCI were enrolled in the multicenter, prospective, observational PERSEO registry (NCT03392948). Primary end point was net adverse clinical events (NACE) with VKA versus DOAC, whereas a secondary prespecified end point was NACE with DAT versus TAT both at 1-year follow-up. From February 2018 to February 2022; in total, 1234 consecutive patients were included. The main indication for OAC was atrial fibrillation (86%), and the mean CHA 2 DS 2 VASc and HAS-BLED scores were 4 ± 2 and 3.6 ± 1, respectively. Of the 1228 patients discharged alive, 222 (18%) were on VKA and 1006 (82%) on DOAC ( P < 0.01). DAT was employed in 197 patients whereas TAT in 1028. At follow-up, NACE rate was significantly higher than VKA compared with DOAC (23% vs. 16%, P = 0.013) and confirmed after propensity score adjustment. TAT and DAT did not differ as regards NACE rate (17% vs. 19%, P = 0.864) although, compared with TAT, DAT was associated with less major bleedings (2% vs. 5%, P = 0.014), confirmed after propensity score adjustment. In conclusion, in patients on OAC undergoing PCI, DOAC, compared with VKA, was associated with a significantly lower occurrence of NACE and DAT reduced bleedings compared with TAT., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Objectives: Patent hemostasis (PH) is essential for preventing radial artery occlusion (RAO) after trans-radial procedures; however, it remains unclear how it should be obtained. The aim of this multicenter randomized study was to evaluate whether the use of an adjustable device (AD), inflated with a pre-determined amount of air (AoA), was more effective than a non-adjustable device (non-AD) for achieving PH, thereby reducing the incidence of RAO., Methods: We enrolled a total of 480 patients undergoing transradial procedure at 3 Italian institutions. Before the procedure, a modified Reverse Barbeau Test (mRBT) was performed in all patients to evaluate the AoA to be eventually inflated in the AD. After the procedure, patients were randomized into 2 groups: (1) AD Group, using TR-Band (Terumo) inflated with the pre-determined AoA; and 2) non-AD Group, using RadiStop (Abbott). An RBT was performed during compression to demonstrate the achievement of PH, as well as 24 hours later to evaluate the occurrence of RAO., Results: PH was more often obtained in the AD Group compared with the non-AD Group (90% vs 64%, respectively, P less than .001), with no difference in terms of bleedings. RAO occurred more often in the non-AD Group compared with the AD Group (10% vs 3%, respectively, P less than .001). Of note, mRBT was effective at guiding AD inflation and identifying high-risk patients in whom PH was more difficult to obtain., Conclusions: The use of AD, filled with a predetermined AoA, allowed PH significantly more often compared with non-AD, providing a significantly reduced incidence of RAO.

Background: Vasoplegic syndrome is a form of vasodilatory shock that can occur before, during or after cardiopulmonary bypass (CPB). We introduce a strategy to reduce the incidence of early hypotension phenomena during Coronary Artery Bypass Graft (CABG) procedures., Materials and Methods: In this prospective cohort study, 100 patients underwent elective CABG with two perioperative CPB settings. The study group (50 patients) was managed with retrograde autologous priming (RAP), 3-minute stepwise for the institution of CPB, and pulsatile flow (PP). The control group (50 patients) was managed without RAP, with the rapid initiation of CPB, and non-pulsatile (NP) flow. The primary endpoints were MAP (mmHg), number of hypotensive phenomena (MAP < 50 mmHg for > 30 sec), the venous return volume on CPB (ml), the cardiac index (L/min/m2), hemoglobin (g/dL), indexed oxygen delivery (DO2i, ml/min/m2), the systemic vascular resistance index (SVRI, dynes s m2/cm5), number of 1-ml boluses of a vasoactive substance (norepinephrine), the positive fluid balance (ml), and the number of red blood cell units for transfusion., Results: During CPB, the mean values in the study and control groups were as follows: MAP, 68± 7 vs 56 ± 7 (p-value, 0.0019); hypotensive phenomena, 3 ± 1 vs 8 ±2 (p-value, 0.019); venous return volume, 840±79 vs 1129 ±123 (p-value, 0.0017); cardiac index, 2.4 ± 0.4 vs 2.7 ±0.2 (p-value, 0.0023); hemoglobin, 9.13 ± 0.29 vs 7.8± 0.23 (p-value, 0.0001); DO2i, 301± 12 vs 276±23 (p-value, 0.0011); SVRI, 1879 ±280 vs 2210 ±140 (p-value, 0.0017); norepinephrine, 1±2 vs 8 ±3 (p-value, 0.0023); positive fluid balance, 750 ±212 vs 1450 ±220 (p-value, 0.005); and total number of red blood cell units for transfusion, 16 ±4.2 vs 27 ± 5.3 (p-value, 0.008)., Conclusions: In this prospective cohort study, during CPB, the study group showed a better preservation of MAP, SVRI, and DO2i, and a reduction of vasoconstrictor use in a CPB setting with the RAP technique, 3-minute stepwise for the initiation of CPB and pulsatile pump flow, compared to the control group. Further studies are needed to validate this perioperative approach to CPB.

Background: Several studies showed that thrombolysis reduces ventricular arrhythmias and improves heart rate variability (HRV) in patients with acute myocardial infarction (AMI). Primary percutaneous coronary intervention (PCI) has recently become the treatment of choice for AMI, but it is still unknown whether it has favorable effects on these prognostic variables., Methods: We studied a group of 44 consecutive AMI patients (39 males, 5 females, mean age 59 +/- 9 years) submitted to primary PCI and 93 consecutive AMI patients (80 males, 13 females, mean age 61.0 +/- 11 years) treated with thrombolytic therapy within 6 hours of symptom onset. All patients underwent 24-hour Holter recording before discharge., Results: The number of premature ventricular beats and the prevalence of non-sustained ventricular tachycardia in the 24 hours were lower in the PCI group (162 +/- 474 and 9%, respectively) than in the thrombolysed group (334 +/- 1730 and 14%, respectively), but the difference did not achieve statistical significance (p = 0.62 and p = 0.58, respectively). There were also no significant differences in HRV variables between the two groups, although a lower proportion of PCI patients tended to have bottom quartile values of HRV variables. The favorable trend for arrhythmias and HRV in PCI patients, however, seemed to be related to a worse basal clinical profile of thrombolysed patients, including a higher prevalence of previous AMI (14 vs 2%, p = 0.065), diabetes (27 vs 18%, p = 0.14) and, in particular, a lower use of beta-blockers (35 vs 93%, p < 0.001)., Conclusions: In this study, we failed to show any significant benefit of primary PCI compared to thrombolysis on ventricular arrhythmias and HRV in patients with ST-segment elevation AMI. The clinical implications of these findings deserve investigation in future studies.