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1.
Europace ; 26(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38306687

RESUMO

AIMS: Data on the hybrid atrial fibrillation (AF) treatment are lacking in patients with structural heart disease undergoing concomitant CryoMaze procedures. The aim was to assess whether the timely pre-emptive catheter ablation would achieve higher freedom from AF or atrial tachycardia (AT) and be associated with better clinical outcomes than surgical ablation alone. METHODS AND RESULTS: The trial investigated patients with non-paroxysmal AF undergoing coronary artery bypass grafting and/or valve repair/replacement with mandatory concomitant CryoMaze procedure who were randomly assigned to undergo either radiofrequency catheter ablation [Hybrid Group (HG)] or no further treatment (Surgery Group). The primary efficacy endpoint was the first recurrence of AF/AT without class I or III antiarrhythmic drugs as assessed by implantable cardiac monitors. The primary clinical endpoint was a composite of hospitalization for arrhythmia recurrence, worsening of heart failure, cardioembolic event, or major bleeding. We analysed 113 and 116 patients in the Hybrid and Surgery Groups, respectively, with a median follow-up of 715 (IQR: 528-1072) days. The primary efficacy endpoint was significantly reduced in the HG [41.1% vs. 67.4%, hazard ratio (HR) = 0.38, 95% confidence interval (CI): 0.26-0.57, P < 0.001] as well as the primary clinical endpoint (19.9% vs. 40.1%, HR = 0.51, 95% CI: 0.29-0.86, P = 0.012). The trial groups did not differ in all-cause mortality (10.6% vs. 8.6%, HR = 1.17, 95%CI: 0.51-2.71, P = 0.71). The major complications of catheter ablation were infrequent (1.9%). CONCLUSION: Pre-emptively performed catheter ablation after the CryoMaze procedure was safe and associated with higher freedom from AF/AT and improved clinical outcomes.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Taquicardia Supraventricular , Humanos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Fibrilação Atrial/tratamento farmacológico , Resultado do Tratamento , Taquicardia Supraventricular/cirurgia , Antiarrítmicos/uso terapêutico , Hemorragia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Recidiva
2.
Europace ; 2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37178136

RESUMO

AIMS: Atrial fibrillation (AF), typical atrial flutter (AFL), and other atrial tachycardias (ATs) are common in patients with pulmonary hypertension. Frequently, several supraventricular arrhythmias are successively observed in individual patients. We investigated the hypothesis of whether more extensive radiofrequency catheter ablation of the bi-atrial arrhythmogenic substrate instead of clinical arrhythmia ablation alone results in superior clinical outcomes in patients with pulmonary arterial hypertension (PH) and supraventricular arrhythmias. METHODS AND RESULTS: Patients with combined post- and pre-capillary or isolated pre-capillary PH and supraventricular arrhythmia indicated to catheter ablation were enrolled in three centres and randomized 1:1 into two parallel treatment arms. Patients underwent either clinical arrhythmia ablation only (Limited ablation group) or clinical arrhythmia plus substrate-based ablation (Extended ablation group). The primary endpoint was arrhythmia recurrence >30 s without antiarrhythmic drugs after the 3-month blanking period. A total of 77 patients (mean age 67 ± 10 years; 41 males) were enrolled. The presumable clinical arrhythmia was AF in 38 and AT in 36 patients, including typical AFL in 23 patients. During the median follow-up period of 13 (interquartile range: 12; 19) months, the primary endpoint occurred in 15 patients (42%) vs. 17 patients (45%) in the Extended vs. Limited ablation group (hazard ratio: 0.97, 95% confidence interval: 0.49-2.0). There was no excess of procedural complications and clinical follow-up events including an all-cause death in the Extended ablation group. CONCLUSION: Extensive ablation, compared with a limited approach, was not beneficial in terms of arrhythmia recurrence in patients with AF/AT and PH. CLINICAL TRIALS REGISTRATION: ClinicalTrials.gov; NCT04053361.

3.
Phys Chem Chem Phys ; 25(9): 6693-6706, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36807663

RESUMO

The role of the oxidation state of cerium cations in a thin oxide film in the adsorption, geometry, and thermal stability of glycine molecules was studied. The experimental study was performed for a submonolayer molecular coverage deposited in vacuum on CeO2(111)/Cu(111) and Ce2O3(111)/Cu(111) films by photoelectron and soft X-ray absorption spectroscopies and supported by ab initio calculations for prediction of the adsorbate geometries, C 1s and N 1s core binding energies of glycine, and some possible products of the thermal decomposition. The molecules adsorbed on the oxide surfaces at 25 °C in the anionic form via the carboxylate oxygen atoms bound to cerium cations. A third bonding point through the amino group was observed for the glycine adlayers on CeO2. In the course of stepwise annealing of the molecular adlayers on CeO2 and Ce2O3, the surface chemistry and decomposition products were analyzed and found to relate to different reactivities of glycinate on Ce4+ and Ce3+ cations, observed as two dissociation channels via C-N and C-C bond scission, respectively. The oxidation state of cerium cations in the oxide was shown to be an important factor, which defines the properties, electronic structure, and thermal stability of the molecular adlayer.

4.
J Appl Biomed ; 21(2): 67-72, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37212155

RESUMO

BACKGROUND: Atrial fibrillation is common in patients with structural heart disease who are undergoing cardiac surgery. Surgical CryoMaze has been shown to be an effective treatment in several trials, but success rates have varied considerably, between 47-95%. The sequential hybrid approach, combining surgical CryoMaze followed by radiofrequency catheter ablation, can achieve high freedom from atrial arrhythmias. However, in patients with concomitant surgical atrial fibrillation treatment, data comparing the hybrid approach to CryoMaze alone are lacking. METHODS: The SurHyb study was designed as a prospective, open-label, multicentre randomized trial. Patients with non-paroxysmal atrial fibrillation who were scheduled for coronary artery bypass grafting or valve repair/replacement were randomized to either surgical CryoMaze alone or surgical CryoMaze followed by radiofrequency catheter ablation 3 months post-surgery. The primary outcome measure was arrhythmia-free survival without class I or III antiarrhythmic drugs, which has been evaluated using implantable cardiac monitors. CONCLUSIONS: This is the first randomized study that compares concomitant surgical CryoMaze alone with the staged hybrid surgical CryoMaze followed by catheter ablation, in patients with non-paroxysmal atrial fibrillation using rigorous rhythm monitoring. The results may contribute to the optimization of the treatment in patients undergoing concomitant CryoMaze for atrial fibrillation.


Assuntos
Fibrilação Atrial , Procedimentos Cirúrgicos Cardíacos , Ablação por Cateter , Humanos , Antiarrítmicos/uso terapêutico , Fibrilação Atrial/cirurgia , Fibrilação Atrial/tratamento farmacológico , Procedimentos Cirúrgicos Cardíacos/métodos , Ablação por Cateter/métodos , Estudos Multicêntricos como Assunto , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
5.
Europace ; 23(4): 539-547, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33305813

RESUMO

AIMS: The aim of this study is to analyse the prevalence, epidemiology, and anticoagulation prevention of stroke or transient ischaemic attack (TIA) in Czech patients with atrial fibrillation (AF). METHODS AND RESULTS: Retrospective observational analysis of diagnoses, procedures, and treatment reported to the Czech National Registry of Reimbursed Healthcare Services between 2015 and 2018. Prevalence of AF in 2018 was 4.3% of Czech population and the prevalence of stroke/TIA in AF patients was 22.3% with annual incidence of 181.62 cases per 100 000 inhabitants. In 2018, CHA2DS2-ASc score ≥4 was present in 98% AF patients in secondary and 59% in primary prevention, respectively, while the anticoagulation treatment was used by 71-81% of them. Between 2015 and 2018, the percentage of AF patients treated with warfarin monotherapy in primary prevention decreased from 35% to 31%, with acetylsalicylic acid (ASA) monotherapy from 18% to 16% and non-vitamin K antagonist oral anticoagulants (NOACs) monotherapy increased from 7% to 11%. In secondary prevention, the percentage of warfarin monotherapy treatment decreased from 35% to 32%, with ASA monotherapy from 20% to 18% and with NOACs monotherapy increased from 9% to 15%. CONCLUSION: This study followed all Czech patients with AF. The unadjusted prevalence and incidence of AF was higher compared with other countries and 2019 European Society of Cardiology Statistics. The study identified several gaps in standard of reimbursed care. 20-30% of AF patients with other risk factors were without any prevention medication and the share of ASA monotherapy in treated patients was 16-18%.


Assuntos
Fibrilação Atrial , Ataque Isquêmico Transitório , Acidente Vascular Cerebral , Administração Oral , Anticoagulantes/uso terapêutico , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/epidemiologia , República Tcheca/epidemiologia , Humanos , Ataque Isquêmico Transitório/diagnóstico , Ataque Isquêmico Transitório/epidemiologia , Ataque Isquêmico Transitório/prevenção & controle , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle
6.
Nat Mater ; 17(7): 592-598, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29867166

RESUMO

Electrocatalysis is at the heart of our future transition to a renewable energy system. Most energy storage and conversion technologies for renewables rely on electrocatalytic processes and, with increasing availability of cheap electrical energy from renewables, chemical production will witness electrification in the near future1-3. However, our fundamental understanding of electrocatalysis lags behind the field of classical heterogeneous catalysis that has been the dominating chemical technology for a long time. Here, we describe a new strategy to advance fundamental studies on electrocatalytic materials. We propose to 'electrify' complex oxide-based model catalysts made by surface science methods to explore electrocatalytic reactions in liquid electrolytes. We demonstrate the feasibility of this concept by transferring an atomically defined platinum/cobalt oxide model catalyst into the electrochemical environment while preserving its atomic surface structure. Using this approach, we explore particle size effects and identify hitherto unknown metal-support interactions that stabilize oxidized platinum at the nanoparticle interface. The metal-support interactions open a new synergistic reaction pathway that involves both metallic and oxidized platinum. Our results illustrate the potential of the concept, which makes available a systematic approach to build atomically defined model electrodes for fundamental electrocatalytic studies.

7.
J Chem Phys ; 151(20): 204703, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31779319

RESUMO

Iridium-based materials are among the most active bifunctional catalysts in heterogeneous catalysis and electrocatalysis. We have investigated the properties of atomically defined Ir/CeO2(111) model systems supported on Cu(111) and Ru(0001) by means of synchrotron radiation photoelectron spectroscopy, resonant photoemission spectroscopy, near ambient pressure X-ray photoelectron spectroscopy (NAP XPS), scanning tunneling microscopy, and temperature programmed desorption. Electronic metal-support interactions in the Ir/CeO2(111) system are accompanied by charge transfer and partial reduction of CeO2(111). The magnitude of the charge transfer depends strongly on the Ir coverage. The Ir/CeO2(111) system is stable against sintering upon annealing to 600 K in ultrahigh vacuum (UHV). Annealing of Ir/CeO2(111) in UHV triggers the reverse oxygen spillover above 450 K. The interaction of hydrogen with Ir/CeO2(111) involves hydrogen spillover and reversible spillover between 100 and 400 K accompanied by the formation of water above 190 K. Formation of water coupled with the strong reduction of CeO2(111) represents the dominant reaction channel upon annealing in H2 above 450 K. The interaction of Ir/CeO2(111) with oxygen has been investigated at moderate and NAP conditions. Additionally, the formation and stability of iridium oxide prepared by deposition of Ir in oxygen atmosphere was investigated upon annealing in UHV and under exposure to H2. The oxidation of Ir nanoparticles under NAP conditions yields stable IrOx nanoparticles. The stability of Ir and IrOx nanoparticles under oxidizing conditions is hampered, however, by encapsulation by cerium oxide above 450 K and additionally by copper and ruthenium oxides under NAP conditions.

8.
J Cardiovasc Electrophysiol ; 29(1): 64-70, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28884872

RESUMO

INTRODUCTION: Frequent ventricular premature complexes (VPCs) may cause symptoms and/or lead to deterioration of LV systolic function. Although frequent VPCs may be abolished by catheter ablation, it may be challenging in case of their origin from the LV papillary muscles (PMs). Our collaborative study aimed to analyze in detail the site of origin and the outcome of ablation. METHODS: Consecutive 34 patients (males: 68%; aged 62 ± 12 years; LV ejection fraction: 50 ± 9%) undergoing catheter ablation of VPCs originating from PMs were included. All procedures were guided by intracardiac echocardiography. RESULTS: The size and shape of PMs were highly variable. The length of anterolateral and posteromedial PM was 23 ± 4 mm and 28 ± 7 mm, respectively. In about one-third of patients, the PM was formed by two distinctly separate heads. The ectopic foci were located on anterolateral, posteromedial or both PM in 35%, 56% and 9% of cases, respectively. Their location was found within the distal, mid, or proximal (basal) third of PM in the 67%, 19%, and 14%, respectively. A total of 86% of PM foci were acutely abolished and long-term success was achieved in 65% of patients. Absence of VPCs of other morphologies and a high burden of ectopic activity before ablation were associated with favorable clinical outcome. CONCLUSION: VPCs originate predominantly from the distal portion of the PM. This knowledge may facilitate the mapping in patients with infrequent ectopic beats. Intracardiac echocardiography is of crucial importance for navigation of the ablation catheter and for assessment of its stability at PM target sites.


Assuntos
Frequência Cardíaca , Ventrículos do Coração/fisiopatologia , Músculos Papilares/fisiopatologia , Função Ventricular Esquerda , Complexos Ventriculares Prematuros/fisiopatologia , Potenciais de Ação , Idoso , Ablação por Cateter , Ecocardiografia , Técnicas Eletrofisiológicas Cardíacas , Europa (Continente) , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Músculos Papilares/diagnóstico por imagem , Músculos Papilares/cirurgia , Fatores de Tempo , Complexos Ventriculares Prematuros/diagnóstico , Complexos Ventriculares Prematuros/cirurgia
9.
Phys Chem Chem Phys ; 20(7): 4688-4698, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-29372205

RESUMO

A model study of adenine adsorption on the Au(111) surface is reported for molecular adlayers prepared by evaporation in vacuum and deposition from saturated aqueous solution. The electronic structure and adsorption geometry of the molecular films were studied experimentally by X-ray photoelectron spectroscopy and near edge X-ray absorption fine structure spectroscopy. Adsorption models are proposed for the adlayers arising from the different preparation methods. Density functional theory calculations were used to examine both parallel and upright adenine adsorption geometries, supply additional information on the bond strength, and identify which atom is involved in bonding to Au(111). In the case of deposition in vacuum, the adenine molecule is bound via van der Waals forces to Au(111) with the molecular plane parallel to the surface, consistent with the published scanning tunneling microscopy data on this system. The most stable parallel adenine configuration was found to have an adsorption energy of ca. -1.1 eV using the optB86b-vdW functional. For adenine deposition from aqueous solution, the adlayer is disordered, with molecules in an upright geometry, and with an adsorption energy of ca. -1.0 eV, coordinated via the imino N3 nitrogen atom. The present study contributes to the substantial literature of model studies of adenine on Au(111), complementing the existing knowledge with information on electronic structure, bonding geometry and adsorption energy of this system.

10.
Nat Mater ; 15(3): 284-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26657332

RESUMO

Electronic interactions between metal nanoparticles and oxide supports control the functionality of nanomaterials, for example, the stability, the activity and the selectivity of catalysts. Such interactions involve electron transfer across the metal/support interface. In this work we quantify this charge transfer on a well-defined platinum/ceria catalyst at particle sizes relevant for heterogeneous catalysis. Combining synchrotron-radiation photoelectron spectroscopy, scanning tunnelling microscopy and density functional calculations we show that the charge transfer per Pt atom is largest for Pt particles of around 50 atoms. Here, approximately one electron is transferred per ten Pt atoms from the nanoparticle to the support. For larger particles, the charge transfer reaches its intrinsic limit set by the support. For smaller particles, charge transfer is partially suppressed by nucleation at defects. These mechanistic and quantitative insights into charge transfer will help to make better use of particle size effects and electronic metal-support interactions in metal/oxide nanomaterials.


Assuntos
Elétrons , Nanopartículas/química , Catálise , Cério/química , Estrutura Molecular , Tamanho da Partícula , Compostos de Platina/química , Propriedades de Superfície
11.
Phys Chem Chem Phys ; 18(11): 7672-9, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-26908194

RESUMO

The reactivity of atomically dispersed Pt(2+) species on the surface of nanostructured CeO2 films and the mechanism of H2 activation on these sites have been investigated by means of synchrotron radiation photoelectron spectroscopy and resonant photoemission spectroscopy in combination with density functional calculations. Isolated Pt(2+) sites are found to be inactive towards H2 dissociation due to high activation energy required for H-H bond scission. Trace amounts of metallic Pt are necessary to initiate H2 dissociation on Pt-CeO2 films. H2 dissociation triggers the reduction of Ce(4+) cations which, in turn, is coupled with the reduction of Pt(2+) species. The mechanism of Pt(2+) reduction involves reverse oxygen spillover and formation of oxygen vacancies on Pt-CeO2 films. Our calculations suggest the existence of a threshold concentration of oxygen vacancies associated with the onset of Pt(2+) reduction.

12.
Eur Neurol ; 73(3-4): 158-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25573455

RESUMO

BACKGROUND: Undetected atrial fibrillation (AF) is often suspected as the possible cause in patients with cryptogenic ischemic stroke (IS), especially in elderly population. In young IS patients, the prevalence of AF, particularly paroxysmal form, remains still not enough established. Our aim was to assess the presence of AF in young patients using a long-term electrocardiography (ECG) Holter monitoring. METHODS: The study set consisted of acute IS patients ≤50 years enrolled in the prospective HISTORY (Heart and Ischemic STrOke Relationship studY) study (NCT01541163). In all patients, admission ECG, serum cardiac markers, transesophageal echocardiography, 24-h and 3-week ECG Holter monitoring were performed. RESULTS: Out of 634 enrolled patients in the HISTORY study, 98 were ≤50 years (56 males, mean age 39.7 ± 8.4). In total, AF was detected in 10.2% of patients and 70% of them had a paroxysmal form of AF. The elevated serum cardiac markers were present in 70% of patients with detected AF (p = 0.0001). CONCLUSION: AF was detected in 10.2% of young stroke patients and paroxysmal form of AF prevailed. Using of long-term ECG Holter monitoring improved the detection of AF. Patients with presence of AF had more frequently elevated serum specific cardiac markers.


Assuntos
Fibrilação Atrial/complicações , Acidente Vascular Cerebral/etiologia , Adulto , Fibrilação Atrial/epidemiologia , Eletrocardiografia , Eletrocardiografia Ambulatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos
13.
Phys Chem Chem Phys ; 16(45): 24747-54, 2014 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-25315100

RESUMO

By means of synchrotron radiation photoemission spectroscopy, we have investigated Pt-CeO2 mixed oxide films prepared on CeO2(111)/Cu(111). Using CO molecules as a probe, we associate the corresponding surface species with specific surface sites. This allows us to identify the changes in the composition and morphology of Pt-CeO2 mixed oxide films caused by annealing in an ultrahigh vacuum. Specifically, two peaks in C 1s spectra at 289.4 and 291.2 eV, associated with tridentate and bidentate carbonate species, are formed on the nanostructured stoichiometric CeO2 film. The peak at 290.5-291.0 eV in the C 1s spectra indicates the onset of restructuring, i.e. coarsening, of the Pt-CeO2 film. This peak is associated with a carbonate species formed near an oxygen vacancy. The onset of cerium oxide reduction is indicated by the peak at 287.8-288.0 eV associated with carbonite species formed near Ce(3+) cations. The development of surface species on the Pt-CeO2 mixed oxides suggests that restructuring of the films occurs above 300 K irrespective of Pt loadings. We do not find any adsorbed CO species associated with Pt(4+) or Pt(2+). The onset of Pt(2+) reduction is indicated by the peak at 286.9 eV in the C 1s spectra due to CO adsorption on metallic Pt particles. The thermal stability of Pt(2+) in Pt-CeO2 mixed oxide depends on Pt loading. We find excellent stability of Pt(2+) for 12% Pt content in the CeO2 film, whereas at a Pt concentration of 25% in the CeO2 film, a large fraction of the Pt(2+) is converted into metallic Pt particles above 300 K.

14.
Phys Chem Chem Phys ; 16(26): 13209-19, 2014 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-24872150

RESUMO

We have studied the interaction of H2 with Pt-Sn nanoalloys supported on Sn-Ce mixed oxide films of different composition by means of synchrotron radiation photoelectron spectroscopy and resonant photoemission spectroscopy. The model catalysts are prepared in a three step procedure that involves (i) the preparation of well-ordered CeO2(111) films on Cu(111) followed by subsequent physical vapor deposition of (ii) metallic Sn and (iii) metallic Pt. The formation of mixed Sn-Ce oxide is accompanied by partial reduction of Ce(4+) cations to Ce(3+). Pt deposition leads to the formation of Pt-Sn nanoalloys accompanied by the partial re-oxidation of Ce(3+) to Ce(4+). Subsequent annealing promotes further Pt-Sn alloy formation at expense of the Sn content in the Sn-Ce mixed oxide. Adsorption of H2 on Pt-Sn/Sn-Ce-O at 150 K followed by stepwise annealing results in reversible reduction of Ce cations caused by spillover of dissociated hydrogen between 150 and 300 K. Above 500 K, annealing of Pt-Sn/Sn-Ce-O in a hydrogen atmosphere results in irreversible reduction of Ce cations. This reduction is caused by the reaction of hydrogen with oxygen provided by the mixed oxide substrate via the reverse spillover to Pt-Sn nanoalloy. The extent of the hydrogen and oxygen spillover strongly depends on the amount of Sn in the Sn-Ce mixed-oxide. We observe an enhancement of hydrogen spillover on Pt-Sn/Sn-Ce-O at low Sn concentration as compared to Sn-free Pt/CeO2. Although the extent of hydrogen spillover on Pt-Sn/Sn-Ce-O with high Sn concentration is comparable to Pt/CeO2, the reverse oxygen spillover is substantially suppressed on these samples.

15.
Angew Chem Int Ed Engl ; 53(39): 10525-30, 2014 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-24919780

RESUMO

Platinum is the most versatile element in catalysis, but it is rare and its high price limits large-scale applications, for example in fuel-cell technology. Still, conventional catalysts use only a small fraction of the Pt content, that is, those atoms located at the catalyst's surface. To maximize the noble-metal efficiency, the precious metal should be atomically dispersed and exclusively located within the outermost surface layer of the material. Such atomically dispersed Pt surface species can indeed be prepared with exceptionally high stability. Using DFT calculations we identify a specific structural element, a ceria "nanopocket", which binds Pt(2+) so strongly that it withstands sintering and bulk diffusion. On model catalysts we experimentally confirm the theoretically predicted stability, and on real Pt-CeO2 nanocomposites showing high Pt efficiency in fuel-cell catalysis we also identify these anchoring sites.

16.
ACS Appl Mater Interfaces ; 16(14): 18099-18111, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38551398

RESUMO

The interface between a metal electrode and an organic semiconductor (OS) layer has a defining role in the properties of the resulting device. To obtain the desired performance, interlayers are introduced to modify the adhesion and growth of OS and enhance the efficiency of charge transport through the interface. However, the employed interlayers face common challenges, including a lack of electric dipoles to tune the mutual position of energy levels, being too thick for efficient electronic transport, or being prone to intermixing with subsequently deposited OS layers. Here, we show that monolayers of 1,3,5-tris(4-carboxyphenyl)benzene (BTB) with fully deprotonated carboxyl groups on silver substrates form a compact layer resistant to intermixing while capable of mediating energy-level alignment and showing a large insensitivity to substrate termination. Employing a combination of surface-sensitive techniques, i.e., low-energy electron microscopy and diffraction, X-ray photoelectron spectroscopy, and scanning tunneling microscopy, we have comprehensively characterized the compact layer and proven its robustness against mixing with the subsequently deposited organic semiconductor layer. Density functional theory calculations show that the robustness arises from a strong interaction of carboxylate groups with the Ag surface, and thus, the BTB in the first layer is energetically favored. Synchrotron radiation photoelectron spectroscopy shows that this layer displays considerable electrical dipoles that can be utilized for work function engineering and electronic alignment of molecular frontier orbitals with respect to the substrate Fermi level. Our work thus provides a widely applicable molecular interlayer and general insights necessary for engineering of charge injection layers for efficient organic electronics.

17.
J Cardiothorac Surg ; 19(1): 397, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937763

RESUMO

OBJECTIVES: Current recommendations support surgical treatment of atrial fibrillation (AF) in patients indicated for cardiac surgery. These procedures are referred to as concomitant and may be carried out using radiofrequency energy or cryo-ablation. This study aimed to assess the electrophysiological findings in patients undergoing concomitant cryo-ablation. METHODS: Patients with non-paroxysmal AF undergoing coronary artery bypass grafting and/or valve repair/replacement were included in the trial if concomitant cryo-ablation was part of the treatment plan according to current guidelines. The patients reported in this study were assigned to undergo staged percutaneous radiofrequency catheter ablation (PRFCA), i.e., hybrid treatment, as a part of the SURHYB trial protocol. RESULTS: We analyzed 103 patients who underwent PRFCA 105 ± 35 days after surgery. Left and right pulmonary veins (PVs) were found isolated in 65 (63.1%) and 63 (61.2%) patients, respectively. The LA posterior wall isolation and mitral isthmus conduction block were found in 38 (36.9%) and 18 (20.0%) patients, respectively. Electrical reconnections (gaps) in the left PVs were more often localized superiorly than inferiorly (57.9% vs. 26.3%, P = 0.005) and anteriorly than posteriorly (65.8% vs. 31.6%, P = 0.003). Gaps in the right PVs were more equally distributed anteroposteriorly but dominated in superior segments (72.5% vs. 40.0%, P = 0.003). There was a higher number of gaps on the roof line compared to the inferior line (131 (67.2%) vs. 67 (42.2%), P < 0.001). Compared to epicardial cryo-ablation, endocardial was more effective in creating PVs and LA posterior wall isolation (P < 0.05). Cryo-ablation using nitrous oxide (N20) or argon (Ar) gas as cooling agents was similarly effective (P = NS). CONCLUSIONS: The effectiveness of surgical cryo-ablation in achieving transmural and durable lesions in the left atrium is surprisingly low. Gaps are located predominantly in the superior and anterior portions of the PVs and on the roof line. Endocardial cryo-ablation is more effective than epicardial ablation, irrespective of the cooling agent used.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Criocirurgia , Veias Pulmonares , Humanos , Fibrilação Atrial/cirurgia , Criocirurgia/métodos , Masculino , Feminino , Ablação por Cateter/métodos , Pessoa de Meia-Idade , Idoso , Veias Pulmonares/cirurgia , Resultado do Tratamento , Ponte de Artéria Coronária/métodos
18.
Chemphyschem ; 14(16): 3673-7, 2013 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-24123498

RESUMO

From a different angle: Thin films of functionalized ionic liquids are deposited on cerium oxides following a surface science approach. The functionalization of the alkyl chain changes its orientation with respect to the surface plane from normal to parallel. This then leads to a different surface chemistry at higher temperatures.

19.
Artigo em Inglês | MEDLINE | ID: mdl-34897297

RESUMO

AIM: Retrospective national sub-analysis of antidiabetic pharmacotherapy in patients with diabetes mellitus (DM) and heart failure (HF) based on data reported to the National Register of Paid Health Services in the Czech Republic between 2012-2018. METHODOLOGY AND RESULTS: In 2012, there were 75,022 patients with HF and DM (i.e. 42.5% of patients with HF), 6 years later 117,265 (i.e. 41.0% of HF patients in 2018). The most represented antidiabetic drug was metformin (45.6%). Of the insulins and analogues, glargine showed the largest positive trend (5.8% 2012; 14.8% 2018). Empagliflozin was the most prescribed SGLT-2 inhibitor (1.8% in 2018). A decrease in prescribing was observed for saxagliptin (0.5% 2012; 0.1% 2018) and for sulfonylurea derivates - gliclazide (13.0% 2012; 10.3% in 2018) and glimepiride (12.9% 2012; 9.0% 2018). Linagliptin was the most prescribed dipeptidyl peptidase inhibitor (0.7% 2012; 6.8% 2018). CONCLUSION: In the Czech Republic, between 2012 and 2008, there was an increase in prevalence of patients with heart failure and concomitant diabetes mellitus, their proportion being similar. In correspondence with other registries, metformin was used mostly. A positive trend was observed in prescription of DDP-4 and SGLT-2 inhibitors, while there was a significant decrease in patients taking sulfonylureas.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Insuficiência Cardíaca , Metformina , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Inibidores da Dipeptidil Peptidase IV/farmacologia , Estudos Retrospectivos , Hipoglicemiantes/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Metformina/efeitos adversos , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico
20.
Artigo em Inglês | MEDLINE | ID: mdl-34916673

RESUMO

BACKGROUND: Clinical parameters linked to a low benefit of ICD implantation and increased mortality risks are needed for an individualized assessment of potential benefits and risks of ICD implantation. METHODS: Analysis of a prospective registry of all patients hospitalized from 2009 to 2019 in a single centre for a first implantation of any type of ICD. RESULTS: A total of 2,681 patients were included in the registry. Until the end of follow-up (38.4 ± 29.1 months), 682 (25.4%) patients died. The one-year mortality in all patients, the one-year CV mortality, the three-year mortality in all patients, and the three-year CV mortality were 7.8%, 5.7%, 20.6%, and 14.8%, respectively. There was a statistically significant difference when the subgroups were compared according to the type of cardiomyopathy. No significant difference was found between primary and secondary prevention and between the types of devices. Male gender, age ≥ 75 years, diabetes mellitus, and atrial fibrillation were associated with a significantly increased mortality risk. CONCLUSION: In an analysis of a long-term follow-up of 2,681 ICD patients, we found no mortality difference between patients with ischemic or non-ischemic cardiomyopathy and in the device type. A higher mortality risk was found in men, patients older than 75 years, diabetics, and those with atrial fibrillation.


Assuntos
Fibrilação Atrial , Cardiomiopatias , Desfibriladores Implantáveis , Humanos , Masculino , Idoso , Fatores de Risco , Morte Súbita Cardíaca/prevenção & controle , Cardiomiopatias/terapia , Sistema de Registros , Resultado do Tratamento
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