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1.
Nature ; 586(7829): 390-394, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33057223

RESUMEN

Owing to its high thermal and electrical conductivities, its ductility and its overall non-toxicity1-3, copper is widely used in daily applications and in industry, particularly in anti-oxidation technologies. However, many widespread anti-oxidation techniques, such as alloying and electroplating1,2, often degrade some physical properties (for example, thermal and electrical conductivities and colour) and introduce harmful elements such as chromium and nickel. Although efforts have been made to develop surface passivation technologies using organic molecules, inorganic materials or carbon-based materials as oxidation inhibitors4-12, their large-scale application has had limited success. We have previously reported the solvothermal synthesis of highly air-stable copper nanosheets using formate as a reducing agent13. Here we report that a solvothermal treatment of copper in the presence of sodium formate leads to crystallographic reconstruction of the copper surface and formation of an ultrathin surface coordination layer. We reveal that the surface modification does not affect the electrical or thermal conductivities of the bulk copper, but introduces high oxidation resistance in air, salt spray and alkaline conditions. We also develop a rapid room-temperature electrochemical synthesis protocol, with the resulting materials demonstrating similarly strong passivation performance. We further improve the oxidation resistance of the copper surfaces by introducing alkanethiol ligands to coordinate with steps or defect sites that are not protected by the passivation layer. We demonstrate that the mild treatment conditions make this technology applicable to the preparation of air-stable copper materials in different forms, including foils, nanowires, nanoparticles and bulk pastes. We expect that the technology developed in this work will help to expand the industrial applications of copper.

2.
BMC Cardiovasc Disord ; 22(1): 400, 2022 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-36071377

RESUMEN

BACKGROUND: Early recurrence (ER) after catheter ablation for atrial fibrillation (AF) has been considered as a common phenomenon but its mechanism and implication in long-term outcome has not been fully elucidated. We aimed to clarify the relation between post-ablation inflammation and ER after cryoballoon ablation (CBA) or radio-frequency ablation (RFA) and evaluate the clinical significance of ER. METHODS: A total of 154 patients with paroxysmal AF undergoing ablation were consecutively recruited, including 90 patients undergoing RFA (RF group) and 64 patients undergoing CBA (CB group). Myocardial injury and inflammation biomarkers were analyzed before and 6 h, 24 h and 48 h after ablation. Acute early recurrence (AER), non-acute early recurrence (NAER) and late recurrence (LR) was defined as recurrence of atrial tachyarrhythmia during 0-3, 4-90 days and beyond a 90-day blanking period after ablation. RESULTS: Cardiac troponin I was significantly higher in CB group while C reactive protein (CRP) and Ratio Neutrophil/Lymphocyte were more elevated in RF group. Higher CRP level after RFA was significantly associated with AER in RF group and lower CRP level after CBA was predictive of AER in CB group. In addition, average cryoablation duration was positively correlated with CRP level after CB group. Cox regression revealed that NAER and left atrial diameter were associated with LR in RF group, while AER and NAER were predictive of LR after CBA. CONCLUSIONS: Post-ablation inflammation was greater in RFA than in CBA. Excessive inflammatory response may be an important factor of AER after RFA. AER after CBA was related with lower inflammation and predictive of LR. Further investigations are still warranted to address on these findings.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Criocirugía , Ablación por Radiofrecuencia , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/cirugía , Ablación por Catéter/efectos adversos , Enfermedad Crónica , Criocirugía/efectos adversos , Humanos , Inflamación
3.
Pacing Clin Electrophysiol ; 45(9): 1015-1023, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35767472

RESUMEN

BACKGROUND: Cryoballoon ablation (CBA) is one of the most commonly used technologies designed for pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF), although the dosing of CBA remains controversial. We evaluated the long-term efficacy and safety of a novel individualized strategy of CBA compared to radiofrequency ablation (RFA) for patients with PAF. METHODS: In this observational study, symptomatic patients with drug-refractory paroxysmal AF were prospectively consented and enrolled in four centers, being assigned either to the CBA or RFA arm for ablation. In the CBA group, we used a time to isolation (TTI) - based dosing protocol. The primary endpoint was the recurrence of atrial arrhythmia >30 s following a 90-day blanking period. The secondary endpoint was procedure-related complications and procedure parameters. RESULTS: A total of 500 patients were recruited in either the CBA group (n = 247) or the RFA group (n = 253) between January 2017 and July 2018. After a median follow-up of 778 days, the atrial tachyarrhythmia-free survival was 71.7% in the CBA group and 67.0% in the RFA group. CBA and RFA displayed similar major or minor complication occurrence, while the former had a significantly shorter procedure duration (82.5 min vs. 141.1 min, p < .001) and left atrial dwell time (60.1 min vs. 109.9 min, p < .001) but longer fluoroscopy exposure (13.8 min vs. 8.1 min, p < .001). CONCLUSION: Compared to RFA, our TTI-based CBA dosing protocol showed comparable efficacy and safety, with a significantly reduced procedure duration in patients with PAF.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Criocirugía , Venas Pulmonares , Ablación por Catéter/métodos , Criocirugía/métodos , Humanos , Venas Pulmonares/cirugía , Recurrencia , Resultado del Tratamiento
4.
Clin Proteomics ; 18(1): 1, 2021 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-33407078

RESUMEN

BACKGROUND: Atrial fibrillation (AF) is the most common cardiac heterogeneous rhythm disorder. It represents a major cause of mortality and morbidity, mainly related to embolic events and heart failure. Mechanisms of AF are complex and remain incompletely understood. Recent evidence suggests exosomes are membrane-coated objects released by many cell-types. Their presence in body fluids and the variable surface composition and content render them attractive as a mechanism for potential biomarkers. However, the content of serum exosomes of AF patients has not been fully delineated. METHODS: In this work, the serum exosomes from AF patients and healthy donors were used to compare changes in the exosome protein content. Exosomes were isolated from serum of AF patients and healthy donors and their purity was confirmed by Western blotting assays and transmission electron microscopy (TEM). Label-free LC-MS/MS quantitative proteomic analysis was applied to analyze protein content of serum exosomes. RESULTS: A total of 440 exosomal protein groups were identified, differentially expressed proteins were filtrated with fold change ≥ 2.0 (AF/controls protein abundance ratio ≥ 2 or ≤ 0.5) and p value less than 0.05 (p < 0.05), significantly changed in abundance group contains 39 elevated proteins and 18 reduced proteins, while consistent presence/absence expression profile group contains 40 elevated proteins and 75 reduced proteins. Bioinformatic analysis of differential exosomal proteins confirmed the significant enrichment of components involved in the anticoagulation, complement system and protein folding. Parallel-Reaction Monitoring Relative Quantitative Analysis (PRM) further suggested that AF related to complement system and protein folding. CONCLUSIONS: These results revealed the composition and potential function of AF serum exosomes, thus providing a new perspective on the complement system and protein folding to AF.

5.
J Cardiovasc Electrophysiol ; 31(3): 658-663, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31975470

RESUMEN

BACKGROUND: Data comparing dabigatran with rivaroxaban regarding the resolution of left atrial/left atrial appendage (LA/LAA) thrombus in patients with nonvalvular atrial fibrillation (AF) are scarce. This study aimed to compare the efficacy and safety of dabigatran vs rivaroxaban regarding the resolution of LA/LAA thrombus in patients with nonvalvular AF. METHODS: This retrospective study enrolled nonvalvular AF patients scheduled to undergo catheter ablation or cardioversion in Shanghai Ruijin Hospital between January 2014 and January 2019. Altogether, 34 patients with LA/LAA thrombus detected by transesophageal echocardiography (TEE) were enrolled. Among them, 12 patients were treated with dabigatran 150 mg bid and the other 22 with rivaroxaban 20 mg qd. Follow-up TEE was performed within greater than or equal to 3 weeks to less than 6 months of the initial TEE to evaluate the resolution of the LA/LAA thrombus. RESULTS: Baseline patient characteristics were similar in the two groups. Overall, 18 patients (81.8%) in the rivaroxaban group had complete thrombus resolution after 70.3 ± 22.1 treatment days, and 10 patients (83.3%) in the dabigatran group had complete thrombus resolution after 69.3 ± 47.9 treatment days. There was no significant difference between the groups (P = .6). TEE showed that the average length, width, and area of thrombus significantly decreased in both groups after treatment, although there was no significant difference in the amount of change in these parameters between the two groups after treatment (P = .6). Undissolved thrombus in two patients in the rivaroxaban group did dissolve after switching to dabigatran. CONCLUSIONS: The results suggest that both dabigatran and rivaroxaban are potential options for treating LA/LAA thrombus in patients with nonvalvular AF. Dabigatran could be an alternative option for the resolution of LA/LAA thrombus resistant to rivaroxaban.


Asunto(s)
Antitrombinas/administración & dosificación , Apéndice Atrial/efectos de los fármacos , Fibrilación Atrial/tratamiento farmacológico , Dabigatrán/administración & dosificación , Inhibidores del Factor Xa/administración & dosificación , Rivaroxabán/administración & dosificación , Accidente Cerebrovascular/prevención & control , Trombosis/tratamiento farmacológico , Administración Oral , Anciano , Antitrombinas/efectos adversos , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/fisiopatología , Fibrilación Atrial/diagnóstico por imagen , Fibrilación Atrial/fisiopatología , Dabigatrán/efectos adversos , Inhibidores del Factor Xa/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Rivaroxabán/efectos adversos , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/fisiopatología , Trombosis/diagnóstico por imagen , Trombosis/fisiopatología , Factores de Tiempo , Resultado del Tratamiento
6.
Cardiovasc Drugs Ther ; 34(3): 323-334, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32297025

RESUMEN

PURPOSE: To compare the effects of class III antiarrhythmic agents (amiodarone vs. ibutilide) on ventricular fibrillation (VF) and hemodynamic status in a canine heart failure (HF) model. METHODS: A total of 12 beagles were used to establish the HF model by rapid pacing for 4 consecutive weeks. These canines were randomly divided into two groups based on the administration of ibutilide and amiodarone. A 12 × 12 unipolar electrode plaque was used for ventricular epicardial mapping, and a 6-electrode plunge needle was inserted for ventricular transmural mapping. The restitution curve was estimated from activation recovery intervals (ARIs) by pacing from the plaque electrodes before and after drug administration. The defibrillation threshold (DFT) and VF activation patterns, including the activation rate, cycle length (VF-CL) and the transmural dispersion of the activation rate, were evaluated and the hemodynamic parameters were mearsured and compared before and after drug administration. RESULTS: Compared to HF baseline, ibutilide administration has markedly decreased the DFT by 28% (18 ± 2 J vs. 13 ± 2.7 J, P < 0.01) without affecting the canine's hemodynamics (mean arterial pressure 91 ± 15 mmHg vs. 92 ± 17 mmHg, P > 0.05). Furthermore, VF activation pattern became more organized, and spontaneous termination was observed only after ibutilide administration. Conversely, amiodarone has significantly compromised the hemodynamic status (mean arterial pressure 92 ± 6.1 mmHg vs. 52 ± 11.6 mmHg, P < 0.05), but did not alter the DFT (17 ± 2.3 J vs. 16 ± 2.0 J, P > 0.05). Compared to pre-medication, both ibutilide and amiodarone have significantly prolonged the VERP (178 ± 9.6 ms vs. 208 ± 8.9 ms, P < 0.05; 185 ± 10.5 ms vs. 202 ± 7.5 ms, P < 0.05, respectively) and reduced the dispersion of refractoriness, the maximal slope of restitution curve, and the epicardial dispersion during pacing. Additionally, both drugs have significantly increased the VF-CL and reduced the transmural dispersion of the VF activation rate. CONCLUSIONS: Ibutilide had potential antifibrillatory properties, which was shown by decreasing the DFT and organizing the VF activation in HF, and with no apparent impact on the hemodynamic status. In contrast, intravenous amiodarone administration demonstrated prominent negative effects on the hemodynamic status possibly by affecting the myocardial contractility before and after defibrillation but did not alter the DFT.


Asunto(s)
Amiodarona/farmacología , Antiarrítmicos/farmacología , Insuficiencia Cardíaca/tratamiento farmacológico , Frecuencia Cardíaca/efectos de los fármacos , Sulfonamidas/farmacología , Fibrilación Ventricular/prevención & control , Potenciales de Acción , Animales , Presión Arterial , Modelos Animales de Enfermedad , Perros , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/fisiopatología , Periodo Refractario Electrofisiológico , Factores de Tiempo , Fibrilación Ventricular/etiología , Fibrilación Ventricular/fisiopatología
7.
J Cardiovasc Electrophysiol ; 30(12): 2929-2935, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31638712

RESUMEN

INTRODUCTION: Catheter ablation of frequent para-Hisian premature ventricular contractions (PH-PVCs) is considered to be challenging. The purpose of this study was to evaluate the strategy, potential technical advantages, and clinical outcomes of remote magnetic navigation (RMN) in the ablation of PH-PVCs. METHODS: Fifteen consecutive patients with PH-PVCs were included in this study. Electrical mapping was initially performed in the right ventricular septum by manipulating the RMN catheter with a "U-curve." In the case of no optimal ablation site or ablation failure, the ablation catheter was directed to the left ventricular (LV) septum through a transseptal approach for further mapping and ablation by manipulating the RMN catheter with a "reverse S-curve." RESULTS: Nine of 15 patients were submitted to ablation on the right side. However, ablation success was only achieved in only three (33%) cases. Of the other 12 patients, 11 underwent LV mapping and ablation. In this subset, 9 of 11 (82%) PH-PVCs were totally eliminated on the left side. Overall, RMN-guided mapping and ablation successfully eliminated 12 (80%) of 15 idiopathic PH-PVCs. During follow-up, the reoccurrence of PVCs was reported in 1 (8%) of 12 patients. No atrioventricular block was observed during or after the procedure. CONCLUSION: RMN-guided catheter ablation for PH-PVCs is effective and safe in unselected patients. Due to the excellent reachability and contact with special morphologies of the RMN catheter on both sides of the ventricular septum, RMN can be considered an effective approach for frequent PH-PVCs.


Asunto(s)
Fascículo Atrioventricular/cirugía , Ablación por Catéter , Magnetismo , Cirugía Asistida por Computador , Complejos Prematuros Ventriculares/cirugía , Potenciales de Acción , Anciano , Fascículo Atrioventricular/fisiopatología , Ablación por Catéter/efectos adversos , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Cirugía Asistida por Computador/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Complejos Prematuros Ventriculares/diagnóstico , Complejos Prematuros Ventriculares/fisiopatología
8.
Exp Physiol ; 104(11): 1630-1637, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31465138

RESUMEN

NEW FINDINGS: What is the central question of this study? Can successful electrical shock in combination with a delayed after-depolarization (DAD) blocker suppress early refibrillation episodes following long duration ventricular fibrillation (LDVF)? What is the main finding and its importance? Flunarizine significantly reduced the activation of LDVF and early ventricular fibrillation (VF) recurrence following LDVF, suggesting that DADs potentially contribute to refibrillation in prolonged VF. Thus, DAD inhibition can be used as an adjunctive therapy for electrical defibrillation to treat prolonged VF and suppress refibrillation following LDVF. ABSTRACT: This study attempts to detect changes in the defibrillation threshold (DFT) at different stages of ventricular fibrillation (VF) (short duration VF, SDVF; long duration VF, LDVF) and during early refibrillation following successful defibrillation of LDVF by giving flunarizine, a blocker of delayed after-depolarizations (DADs). Twelve beagles were divided into two groups (the control group, n = 6; and the flunarizine group, n = 6). Two 64-electrode basket catheters were deployed into the left and the right ventricles for global endocardium mapping. The DFTs of SDVF and LDVF were determined at 20 s and 7 min, respectively, after VF induction in each group. Any refibrillation episodes were recorded within 15 min after the first successful defibrillation of LDVF. In the flunarizine group, the SDVF-DFT values before and after the drug were not significantly different. The 7 min LDVF-DFTs were markedly reduced by 26% (P < 0.05, the control group) and 38% (P < 0.01, the flunarizine group) compared to the 20 s SDVF-DFTs within each group. The difference between SDVF-DFT and LDVF-DFT after flunarizine was larger than that in the control group (213 ± 65 vs. 120 ± 84 V, P < 0.05). The number of refibrillation episodes per animal (1.3 ± 1.0) following successful defibrillation of LDVF after flunarizine was 48% of that in controls (2.7 ± 2.0, P < 0.05). The effect of flunarizine on SDVF-DFT and LDVF-DFT indicates that the role of DADs in the defibrillation mechanism may differ as VF continues. Flunarizine significantly reduced early VF recurrence following LDVF, suggesting that DADs potentially contribute to refibrillation in a canine model of prolonged VF.


Asunto(s)
Flunarizina/farmacología , Ventrículos Cardíacos/efectos de los fármacos , Fibrilación Ventricular/tratamiento farmacológico , Animales , Arritmias Cardíacas/tratamiento farmacológico , Modelos Animales de Enfermedad , Perros , Cardioversión Eléctrica/métodos , Endocardio/efectos de los fármacos , Femenino , Masculino , Factores de Tiempo
9.
Exp Physiol ; 103(1): 19-30, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29094471

RESUMEN

NEW FINDINGS: What is the central question of this study? In the present study, we investigated the effects of renal denervation on the vulnerability to ventricular fibrillation and the ventricular electrical properties in a rapid pacing-induced heart failure canine model. What is the main finding and its importance? Renal denervation significantly attenuated the process of heart failure and improved left ventricular systolic dysfunction, stabilized ventricular electrophysiological properties and decreased the vulnerability of the heart to ventricular fibrillation during heart failure. Thus, renal denervation can attenuate ventricular electrical remodelling and exert a potential antifibrillatory action in a pacing-induced heart failure canine model. In this study, we investigated the effects of renal denervation (RDN) on the vulnerability to ventricular fibrillation (VF) and the ventricular electrical properties in a canine model of pacing-induced heart failure (HF). Eighteen beagles were divided into the following three groups: control (n = 6), HF (n = 6) and HF+RDN (n = 6). Heart failure was induced by rapid right ventricular pacing. Renal denervation was performed simultaneously with the pacemaker implantation in the HF+RDN group. A 64-unipolar basket catheter was used to perform global endocardial mapping of the left ventricle. The restitution properties and dispersion of refractoriness were estimated from the activation recovery intervals (ARIs) by a pacing protocol. The VF threshold (VFT) was defined as the maximal pacing cycle length required to induce VF using a specific pacing protocol. The defibrillation threshold (DFT) was measured by an up-down algorithm. Renal denervation partly restored left ventricular systolic function and attenuated the process of HF. Compared with the control group, the VFT in the HF group was decreased by 27% (106 ± 8.0 versus 135 ± 10 ms, P < 0.01). However, RDN increased the VFT by 13% (135 ± 10 versus 118 ± 7.5 ms, P < 0.05) and decreased the DFT by 27% (30 ± 6.3 versus 21.8 ± 4.7 J, P < 0.05) in the treated hearts compared with the failing hearts. Renal denervation significantly flattened the ventricular ARI restitution curve by 15% (1.48 ± 0.2 versus 1.26 ± 0.11, P < 0.05) and decreased the dispersion of ARI by 25% (0.08 ± 0.02 versus 0.06 ± 0.01, P < 0.01) in the treated group compared with the HF group. The findings of this study suggest that RDN can attenuate ventricular electrical remodelling and exert a potential antifibrillatory action on VF in a canine model of pacing-induced HF.


Asunto(s)
Estimulación Cardíaca Artificial/efectos adversos , Desnervación/tendencias , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/terapia , Riñón/inervación , Fibrilación Ventricular/diagnóstico por imagen , Fibrilación Ventricular/prevención & control , Animales , Desnervación/métodos , Perros , Insuficiencia Cardíaca/fisiopatología , Riñón/diagnóstico por imagen , Riñón/cirugía , Fibrilación Ventricular/fisiopatología
10.
Langmuir ; 34(9): 2942-2951, 2018 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-29433306

RESUMEN

Like their biogenic counterparts, synthetic minerals with hierarchical architectures should exhibit multiple structural functions, which nicely bridge the boundaries between engineering and functional materials. Nevertheless, design of bioinspired mineralization approaches to thin coatings with distinct micro/nanotextures remains challenging in the realm of materials chemistry. Herein, a general morphosynthetic method based on seeded mineralization was extended to achieve prismatic-type thin CaCO3 coatings on fibrous substrates for oil/water separation applications. Distinct micro/nanotextures of the overlayers could be obtained in mineralization processes in the presence of different soluble (bio)macromolecules. These hierarchical thin coatings therefore exhibit multiple structural functions including underwater superoleophobicity, ultralow adhesion force of oil in water, and comparable stiffness/strength to the prismatic-type biominerals found in mollusk shells. Moreover, this controllable approach could proceed on fibrous substrates to obtain robust thin coatings, so that a modified nylon mesh could be employed for oil/water separation driven by gravity. Our bioinspired approach based on seeded mineralization opens the door for the deposition of hierarchical mineralized thin coatings exhibiting multiple structural functions on planar and fibrous substrates. This bottom-up strategy could be readily extended for the syntheses of advanced thin coatings with a broad spectrum of engineering and functional constituents.

11.
J Cardiovasc Electrophysiol ; 28(12): 1387-1392, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28862806

RESUMEN

BACKGROUND: There have been advancements of sophisticated mapping systems used for ablation procedures over the last decade. Utilization of these novel mapping systems in combination with remote magnetic navigation (RMN) needs to be established. We investigated the new EnSite Precision mapping system (St. Jude Medical, Inc., St. Paul, MN, USA), which collects magnetic data for checking navigation field stability and is built on an open platform, allowing physicians to choose diagnostic and ablation catheters. We address its compatibility with RMN. OBJECTIVE: To assess the clinical utility of a novel 3D mapping system (EnSite Precision mapping system) combined with RMN (Niobe ES, Stereotaxis, Inc., St. Louis, MO, USA) for atrial fibrillation (AF) ablation. METHODS: In this prospective nonrandomized study, two groups of patients were treated in our center for drug refractory AF. Patients were consecutively enrolled in each group. Group A (n = 35, 14 persistent AF [PsAF]) was treated using the novel 3D mapping system combined with RMN. Group B (n = 38, 16 PsAF) was treated using Carto® 3 (Biosense Webster, Inc., Diamond Bar, CA, USA) combined with RMN. In Group A, the left atrium (LA) was mapped with a circular magnetic catheter manually and was then replaced by a RMN ablation catheter. At the end of the procedures in Group A, the circular catheter was used for confirming field stability. In Group B, an ablation catheter was controlled by RMN to perform both LA mapping and ablation. All patients underwent pulmonary vein antrum isolation. Additional complex fractionated atrial electrograms (CFAEs) ablation was performed for PsAF. Procedural, ablation, and fluoroscopy times were recorded and complications were assessed. RESULTS: Electrophysiological end points were achieved in all patients. Using the novel mapping system, LA mapping time was fast (308 ± 60 seconds) with detailed anatomy points (178,831 ± 70,897) collected and magnetic points throughout LA. At the end of the procedures in Group A, the LA model was confirmed to be stable and its location was within the distance threshold (1 mm). Procedure time (117.9 ± 29.6 minutes vs. 119.2 ± 29.7 minutes, P = 0.89), fluoroscopy time (6.1 ± 2.4 minutes vs. 4.8 ± 2.2 minutes, P = 0.07), and ablation time (28.0 ± 12.9 minutes vs. 27.9 ± 15.8 minutes, P = 0.98) were similar in Group A versus Group B, respectively. No complications occurred in either group. CONCLUSIONS: LA mapped by the novel system is stable and reliable. Combined with RMN, it could be effectively used for AF ablation without impacting overall procedural times.


Asunto(s)
Fibrilación Atrial/diagnóstico por imagen , Fibrilación Atrial/cirugía , Mapeo del Potencial de Superficie Corporal/métodos , Ablación por Catéter/métodos , Imagenología Tridimensional/métodos , Anciano , Femenino , Humanos , Fenómenos Magnéticos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
12.
BMC Cardiovasc Disord ; 17(1): 99, 2017 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-28407744

RESUMEN

BACKGROUND: The objective of this study was to detect differences in the distribution of the left and right ventricle (LV & RV) activation rate (AR) during short-duration ventricular fibrillation (SDVF, <1 min) and long-duration ventricular fibrillation VF (LDVF, >1 min) in normal and heart failure (HF) canine hearts. METHODS: Ventricular fibrillation (VF) was electrically induced in six healthy dogs (control group) and six dogs with right ventricular pacing-induced congestive HF (HF group). Two 64-electrode basket catheters deployed in the LV and RV were used for global endocardium electrical mapping. The AR of VF was estimated by fast Fourier transform analysis from each electrode. RESULTS: In the control group, the LV was activated faster than the RV in the first 20 s, after which there was no detectable difference in the AR between them. When analyzing the distribution of the AR within the bi-ventricles at 3 min of LDVF, the posterior LV was activated fastest, while the anterior was slowest. In the HF group, a detectable AR gradient existed between the two ventricles within 3 min of VF, with the LV activating more quickly than the RV. When analyzing the distribution of the AR within the bi-ventricles at 3 min of LDVF, the septum of the LV was activated fastest, while the anterior was activated slowest. CONCLUSIONS: A global bi-ventricular endocardial AR gradient existed within the first 20 s of VF but disappeared in the LDVF in healthy hearts. However, the AR gradient was always observed in both SDVF and LDVF in HF hearts. The findings of this study suggest that LDVF in HF hearts can be maintained differently from normal hearts, which accordingly should lead to the development of different management strategies for LDVF resuscitation.


Asunto(s)
Cardioversión Eléctrica/métodos , Sistema de Conducción Cardíaco/fisiopatología , Insuficiencia Cardíaca/fisiopatología , Frecuencia Cardíaca/fisiología , Ventrículos Cardíacos/fisiopatología , Fibrilación Ventricular/fisiopatología , Animales , Mapeo del Potencial de Superficie Corporal , Modelos Animales de Enfermedad , Perros , Endocardio , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/terapia , Fibrilación Ventricular/complicaciones , Fibrilación Ventricular/terapia
13.
Pacing Clin Electrophysiol ; 40(10): 1067-1072, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28703873

RESUMEN

OBJECTIVES: We assessed the effectiveness and safety of cryoballoon ablation (CBA) in the Chinese population with paroxysmal atrial fibrillation (AF) with a 1-year follow-up and determined the association of early recurrence of atrial tachyarrhythmias (ERAT) with late recurrence (LR). METHODS: A total of 114 patients (age 61 ± 10 years, 78 males) with paroxysmal AF who underwent CBA were consecutively enrolled. After procedures, patients were observed for 3 days with continuous electrocardiogram monitoring in the hospital with routine follow-up visits at 3 months, 6 months, and 1 year. Documented atrial tachyarrhythmia >30 seconds was defined as recurrence. ERAT was defined as any recurrence during the first 3 months, and LR was recurrence between 3 and 12 months. RESULTS: With the first 3 months as blanking period, 76% of patients were free of LR at 12 months. Five patients (4%) experienced complications, including phrenic nerve palsy, stroke, and groin complications. Forty-five percent of patients had ERAT in the first 3 months and 31% of patients had ERAT in the first 3 days. Patients with ERAT had higher LR rate (LRR) than those without ERAT (43% vs 8%, P < 0.001). The LRR of patients with ERAT only in the first 3 days was lower than those with ERAT both in the first 3 days and in 4-90 days (29% vs 64%, P = 0.036). CONCLUSIONS: CBA was an effective and safe treatment option for paroxysmal AF. Patients with ERAT had higher LRR after CBA of AF. The time when ERAT occurred had an impact on LRR.


Asunto(s)
Fibrilación Atrial/cirugía , Ablación por Catéter/métodos , Criocirugía , Pueblo Asiatico , Procedimientos Quirúrgicos Cardíacos/métodos , Ablación por Catéter/instrumentación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
14.
Small ; 11(12): 1436-42, 2015 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-25363306

RESUMEN

By using one-dimensional rutile TiO(2) nanorod arrays as the structure-directing scaffold as well as the TiO(2) source to two consecutive hydrothermal reactions, densely aligned SrTiO(3) -modified rutile TiO(2) heterojunction photocatalysts are crafted for the first time. The first hydrothermal processing yielded nanostructured rutile TiO(2) with the hollow openings on the top of nanorods (i.e., partially etched rutile TiO(2) nanorod arrays; denoted PE-TNRAs). The subsequent second hydrothermal treatment in the presence of Sr(2+) transforms the surface of partially etched rutile TiO(2) nanorods into SrTiO(3) nanoparticles via the concurrent dissolution of TiO(2) and precipitation of SrTiO(3) while retaining the cylindrical shape (i.e., forming SrTiO(3) -decorated rutile TiO(2) composite nanorods; denoted STO-TNRAs). The structural and composition characterizations substantiate the success in achieving STO-TNRA nanostructures. In comparison to PE-TNRAs, STO-TNRA photocatalysts exhibit higher photocurrents and larger photocatalytic degradation rates of methylene blue (3.21 times over PE-TNRAs) under UV light illumination as a direct consequence of improved charge carrier mobility and enhanced electron/hole separation. Such 1D perovskite-decorated semiconductor nanoarrays are very attractive for optoelectronic applications in photovoltaics, photocatalytic hydrogen production, among other areas.

15.
Croat Med J ; 55(2): 121-7, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24778098

RESUMEN

AIM: To determine the role of repetitive endocardial focal activations and Purkinje fibers in the maintenance of long duration ventricular fibrillation (LDVF, VF>1 minute) in canine hearts in vivo. METHODS: The study was conducted in electrophysiological laboratory of Shanghai Ruijin hospital from July 2010 to August 2012. A 64-electrode basket was introduced through a carotid artery into the left ventricle (LV) of 11 beagle dogs for global endocardial electrical mapping. In the Lugol's solution group (n=5), the subendocardium was ablated by washing with Lugol's solution. In the control group, (n=6) saline was used for ablation. Before and after saline or Lugol ablation, we determined QRS duration and QT/QTc interval in sinus rhythm (SR). We also measured the activation rates in the first 2 seconds of each minute during 7 minutes of VF for each group. If VF terminated spontaneously in less than 7 minutes, the VF segments used in activation rate analysis were reduced accordingly. RESULTS: At the beginning of VF there was no difference between the groups in the activation rate. However, after 1 minute of LDVF the Lugol's solution group had significantly slower activation rate than the control group. In the control group, all episodes of LDVF (6/6) were successfully sustained for 7 minutes, while in the Lugol's solution group 4/5 episodes of LDVF spontaneously terminated before 7 minutes (4.8±1.4 minutes) (P=0.015). In the control group, at 5.1±1.3 minutes of LDVF, a successive, highly organized focal LV endocardial activation pattern was observed. During this period, activations partly arose in PF and spread to the working ventricular myocardium. Mapping analysis showed that these events were consistent with repetitive endocardial focal activations. No evidence of similar focal activations was observed in the Lugol's solution group. CONCLUSIONS: Repetitive endocardial focal activations in the LV endocardium may be associated with activation of subendocardial PFs. This mechanism may play an important role in the maintenance of LDVF.


Asunto(s)
Endocardio/fisiopatología , Ramos Subendocárdicos/fisiopatología , Fibrilación Ventricular/fisiopatología , Potenciales de Acción/fisiología , Animales , Perros , Cardioversión Eléctrica , Yoduros , Masculino , Factores de Tiempo
16.
Int Immunopharmacol ; 132: 111894, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38569426

RESUMEN

AIMS: To investigate the immunology shared mechanisms underlying chronic obstructive pulmonary disease (COPD) and type 2 diabetes mellitus (T2DM) and examine the impact of anti-diabetic drugs on acute exacerbation of COPD (AECOPD). METHODS: We analyzed GSE76925, GSE76894, GSE37768, and GSE25724 to identify differentially expressed genes. Hub-genes were identified through protein-protein interaction network analysis and evaluated by the receiver operating characteristic curve. CXCL12 emerged as a robust biomarker, and its correlation with lung function and CD8+ T cells were further quantified and validated. The activated signaling pathways were inferred through Gene set enrichment analysis (GSEA). The retrospective clinical analysis was executed to identify the influence of dipeptidyl peptidase-4 inhibitors (DPP-4i) on CXCL12 and evaluate the drug's efficacy in AECOPD. RESULTS: The significant up-regulation of CXCL12 expression in patients with two diseases were revealed. CXCL12 exhibited a negative correlation with pulmonary function (r = -0.551, p < 0.05). Consistent with analysis in GSE76925 and GSE76894, the positive correlation between the proportion of CD8+ T cells was demonstrated(r=0.469, p<0.05). GSEA identified "cytokines interaction" as an activated signaling pathway, and the clinical study revealed the correlation between CXCL12 and IL-6 (r=0.668, p<0.05). In patients with COPD and T2DM, DDP-4i treatment exhibited significantly higher serum CXCL12, compared to GLP-1RA. Analysis of 187 COPD patients with T2DM indicated that the DPP-4i group had a higher frequency of AECOPD compared to the GLP-1RA group (OR 1.287, 95%CI [1.018-2.136]). CONCLUSIONS: CXCL12 may represent a therapeutic target for COPD and T2DM. GLP-1RA treatment may be associated with lower CXCL12 levels and a lower risk of AECOPD compared to DPP-4i treatment. CLINICAL TRIAL REGISTRATION: China Clinical Trial Registration Center(ChiCTR2200055611).


Asunto(s)
Quimiocina CXCL12 , Biología Computacional , Diabetes Mellitus Tipo 2 , Inhibidores de la Dipeptidil-Peptidasa IV , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Masculino , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Inhibidores de la Dipeptidil-Peptidasa IV/farmacología , Femenino , Anciano , Persona de Mediana Edad , Estudios Retrospectivos , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Progresión de la Enfermedad , Mapas de Interacción de Proteínas
17.
Clin Chim Acta ; 553: 117703, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38097129

RESUMEN

BACKGROUND: We aimed to identify plasma biomarkers of atrial fibrillation (AF) progression and recurrence after catheter ablation. METHODS: Using AF gene profiling data from GEO database, a weighted gene co-expression network analysis (WGCNA) was conducted to determine the most significant module and hub genes associated with AF. Subsequently, 318 consecutively admitted patients who had undergone radiofrequency catheter ablation were enrolled in this study. RESULTS: WGCNA results revealed that paired immunoglobulin-like type 2 receptor alpha (PILRA) was the only black module gene highly correlated with clinical traits. Plasma soluble PILRα (sPILRα) levels were elevated in patients with AF and significantly elevated in patients with persistent versus paroxysmal AF (4.64 ± 2.74 vs. 3.04 ± 1.56 ng/mL, p < 0.001). Elevated sPILRα level was an independent risk factor for AF progression even after adjusting for traditional factors (adjusted odds ratio: 3.06, 95 % confidence interval [CI]: 1.88-5.27, p < 0.001) and AF recurrence after catheter ablation in patients with persistent AF (adjusted hazards ratio: 4.41, 95 % CI: 1.22-15.92, p = 0.023). CONCLUSIONS: WGCNA screening of GEO microarray gene profiling data showed PILRA expression levels to be correlated with AF progression and recurrence after catheter ablation in patients with persistent AF.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Humanos , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/genética , Fibrilación Atrial/cirugía , Resultado del Tratamiento , Recurrencia , Factores de Riesgo , Biomarcadores
18.
Small ; 9(2): 312-21, 2013 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-23047462

RESUMEN

Dye-sensitized solar cells (DSSCs) based on hierarchical rutile TiO(2) flower clusters prepared by a facile, one-pot hydrothermal process exhibit a high efficiency. Complex yet appealing rutile TiO(2) flower films are, for the first time, directly hydrothermally grown on a transparent conducting fluorine-doped tin oxide (FTO) substrate. The thickness and density of as-grown flower clusters can be readily tuned by tailoring growth parameters, such as growth time, the addition of cations of different valence and size, initial concentrations of precursor and cation, growth temperature, and acidity. Notably, the small lattice mismatch between the FTO substrate and rutile TiO(2) renders the epitaxial growth of a compact rutile TiO(2) layer on the FTO glass. Intriguingly, these TiO(2) flower clusters can then be exploited as photoanodes to produce DSSCs, yielding a power conversion efficiency of 2.94% despite their rutile nature, which is further increased to 4.07% upon the TiCl(4) treatment.

19.
Small ; 9(17): 2945-53, 2013 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-23420792

RESUMEN

Binary wettability patterned surfaces with extremely high wetting contrasts can be found in nature on living creatures. They offer a versatile platform for microfluidic management. In this work, a facile approach to fabricating erasable and rewritable surface patterns with extreme wettability contrasts (superhydrophilic/superhydrophobic) on a TiO2 nanotube array (TNA) surface through self-assembly and photocatalytic lithography is reported. The multifunctional micropatterned superhydrophobic TNA surface can act as a 2D scaffold for site-selective cell immobilization and reversible protein absorption. Most importantly, such a high-contrast wettability template can be used to construct various well-defined 3D functional patterns, such as calcium phosphate, silver nanoparticles, drugs, and biomolecules in a highly selective manner. The 3D functional patterns would be a versatile platform in a wide range of applications, especially for biomedical devices (e.g., high-throughput molecular sensing, targeted antibacterials, and drug delivery). In a proof-of-concept study, the surface-enhanced Raman scattering and antibacterial performance of the fabricated 3D AgNP@TNA pattern, and the targeted drug delivery for site-specific and high-sensitivity cancer cell assays was investigated.


Asunto(s)
Nanotubos/química , Titanio/química , Humectabilidad , Nanotecnología , Propiedades de Superficie
20.
Phys Chem Chem Phys ; 15(11): 4041-8, 2013 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-23400011

RESUMEN

A highly ordered TiO(2) nanotube array film was fabricated by an anodic oxidation method. The film was modified by Au nanoparticles (NPs) formed by a deposition-precipitation technique and was covered with a thin ZnS shell prepared by a successive ionic layer adsorption and reaction (SILAR) method. The photoelectrochemical properties of the prepared ZnS/Au/TiO(2) composite film were evaluated by incident photon-to-current conversion efficiency (IPCE), and photopotential and electrochemical impedance spectroscopy (EIS) measurements under white light illumination. The results indicated that the Au NPs could expand the light sensitivity range of the film and suppress the electron-hole recombination, and the ZnS shell could inhibit the leakage of photogenerated electrons from the surface of Au NPs to the ZnS/electrolyte interface. When the 403 stainless steel in a 0.5 M NaCl solution was coupled to the ZnS/Au/TiO(2) nanotube film photoanode under illumination, its potential decreased by 400 mV, showing that the composite film had a better photocathodic protection effect on the steel than that of a pure TiO(2) nanotube film.

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