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1.
Cell Mol Life Sci ; 81(1): 88, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38349408

RESUMEN

Atrial fibrillation (AF) is the most prevalent sustained cardiac arrhythmia, and recent epidemiological studies suggested type 2 diabetes mellitus (T2DM) is an independent risk factor for the development of AF. Zinc finger and BTB (broad-complex, tram-track and bric-a-brac) domain containing 16 (Zbtb16) serve as transcriptional factors to regulate many biological processes. However, the potential effects of Zbtb16 in AF under T2DM condition remain unclear. Here, we reported that db/db mice displayed higher AF vulnerability and Zbtb16 was identified as the most significantly enriched gene by RNA sequencing (RNA-seq) analysis in atrium. In addition, thioredoxin interacting protein (Txnip) was distinguished as the key downstream gene of Zbtb16 by Cleavage Under Targets and Tagmentation (CUT&Tag) assay. Mechanistically, increased Txnip combined with thioredoxin 2 (Trx2) in mitochondrion induced excess reactive oxygen species (ROS) release, calcium/calmodulin-dependent protein kinase II (CaMKII) overactivation, and spontaneous Ca2+ waves (SCWs) occurrence, which could be inhibited through atrial-specific knockdown (KD) of Zbtb16 or Txnip by adeno-associated virus 9 (AAV9) or Mito-TEMPO treatment. High glucose (HG)-treated HL-1 cells were used to mimic the setting of diabetic in vitro. Zbtb16-Txnip-Trx2 signaling-induced excess ROS release and CaMKII activation were also verified in HL-1 cells under HG condition. Furthermore, atrial-specific Zbtb16 or Txnip-KD reduced incidence and duration of AF in db/db mice. Altogether, we demonstrated that interrupting Zbtb16-Txnip-Trx2 signaling in atrium could decrease AF susceptibility via reducing ROS release and CaMKII activation in the setting of T2DM.


Asunto(s)
Fibrilación Atrial , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Animales , Ratones , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina , Proteínas Portadoras/genética , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/genética , Proteína de la Leucemia Promielocítica con Dedos de Zinc , Especies Reactivas de Oxígeno , Tiorredoxinas/genética
2.
New Phytol ; 241(3): 1161-1176, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37964659

RESUMEN

Lignin contributes to plant mechanical properties during bending loads. Meanwhile, phytohormone auxin controls various plant biological processes. However, the mechanism of auxin's role in bending-induced lignin biosynthesis was unclear, especially in bamboo, celebrated for its excellent deformation stability. Here, we reported that auxin response factors (ARF) 3 and ARF6 from Moso bamboo (Phyllostachys edulis (Carrière) J. Houz) directly regulate lignin biosynthesis pathway genes, and affect lignin biosynthesis in bamboo. Auxin and lignin exhibited asymmetric distribution patterns, and auxin promoted lignin biosynthesis in response to bending loads in bamboo. Employing transcriptomic and weighted gene co-expression network analysis approach, we discovered that expression patterns of ARF3 and ARF6 strongly correlated with lignin biosynthesis genes. ARF3 and ARF6 directly bind to the promoter regions of 4-coumarate: coenzyme A ligase (4CL3, 4CL7, and 4CL9) or caffeoyl-CoA O-methyltransferase (CCoAOMT2) genes, pivotal to lignin biosynthesis, and activate their expressions. Notably, the efficacy of this binding hinges on auxin levels. Alternation of the expressions of ARF3 and ARF6 substantially altered lignin accumulation in transgenic bamboo. Collectively, our study shed light on bamboo lignification genetics. Auxin signaling could directly modulate lignin biosynthesis genes to impact plant lignin content.


Asunto(s)
Ácidos Indolacéticos , Lignina , Ácidos Indolacéticos/metabolismo , Lignina/metabolismo , Poaceae/genética , Transcriptoma , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas
3.
Opt Lett ; 49(16): 4662-4665, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39146129

RESUMEN

The bulk photovoltaic (BPV) effect in ferroelectric liquid crystals is of increasing scientific interest owing to its great potential for light-energy conversion. The ferroelectric nematic phase exhibits a huge spontaneous polarization that can be aligned to a preferred direction. In this Letter, we investigate the tensorial properties of the BPV effect in the planarly aligned ferroelectric nematic phase of the liquid crystalline material RM734. A steady-state short-circuit photocurrent of ~160 pA and an open-circuit photovoltage of ~50 mV were observed in a cell with a thickness of 5.5 µm under the illumination of ultraviolet light without any bias voltage. Based on the photocurrent measurements in different electrode configurations, the non-zero elements of the BPV tensor were obtained. The BPV effect is attributed to the combination of the spontaneous polarization and the asymmetric distribution of photoinduced charge carriers. This study not only provides an understanding of the bulk PV mechanism in soft ferroelectrics but also promises a wide range of unprecedented, to the best of our knowledge, benefits for light harvesting to engineer marketable photovoltaic devices.

4.
Ann Noninvasive Electrocardiol ; 29(1): e13097, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37997698

RESUMEN

The ECG diagnosis of LVH is predominantly based on the QRS voltage criteria. The classical paradigm postulates that the increased left ventricular mass generates a stronger electrical field, increasing the leftward and posterior QRS forces, reflected in the augmented QRS amplitude. However, the low sensitivity of voltage criteria has been repeatedly documented. We discuss possible reasons for this shortcoming and proposal of a new paradigm. The theoretical background for voltage measured at the body surface is defined by the solid angle theorem, which relates the measured voltage to spatial and non-spatial determinants. The spatial determinants are represented by the extent of the activation front and the distance of the recording electrodes. The non-spatial determinants comprise electrical characteristics of the myocardium, which are comparatively neglected in the interpretation of the QRS patterns. Various clinical conditions are associated with LVH. These conditions produce considerable diversity of electrical properties alterations thereby modifying the resultant QRS patterns. The spectrum of QRS patterns observed in LVH patients is quite broad, including also left axis deviation, left anterior fascicular block, incomplete and complete left bundle branch blocks, Q waves, and fragmented QRS. Importantly, the QRS complex can be within normal limits. The new paradigm stresses the electrophysiological background in interpreting QRS changes, i.e., the effect of the non-spatial determinants. This postulates that the role of ECG is not to estimate LV size in LVH, but to understand and decode the underlying electrical processes, which are crucial in relation to cardiovascular risk assessment.


Asunto(s)
Sistema de Conducción Cardíaco , Hipertrofia Ventricular Izquierda , Humanos , Hipertrofia Ventricular Izquierda/diagnóstico , Electrocardiografía , Arritmias Cardíacas , Bloqueo de Rama
5.
J Mol Cell Cardiol ; 182: 57-72, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37482037

RESUMEN

Hypertension-induced tunica media thickening (TMT) is the most important fundamental for the subsequent complications like stroke and cardiovascular diseases. Pathogenically, TMT originates from both vascular smooth muscle cells (VSMCs) hypertrophy due to synthesizing more amount of intracellular contractile proteins and excess secretion of extracellular matrix. However, what key molecules are involved in the pathogenesis of TMT is unknown. We hypothesize that formin homology 2 domain-containing protein 1 (FHOD1), an amply expressed mediator for assembly of thin actin filament in VSMCs, is a key regulator for the pathogenesis of TMT. In this study, we found that FHOD1 expression and its phosphorylation/activation were both upregulated in the arteries of three kinds of hypertensive rats. Ang-II induced actin filament formation and hypertrophy through activation and upregulation of FHOD1 in VSMCs. Active FHOD1-mediated actin filament assembly and secretions of collagen-1α/collagen-3α played crucial roles in Ang-II-induced VSMCs hypertrophy in vitro and hypertensive TMT in vivo. Proteomics demonstrated that activated FL-FHOD1 or its C-terminal diaphanous-autoregulatory domain significantly upregulated RNF213 (ring finger protein 213), a 591-kDa cytosolic E3 ubiquitin ligase with its loss-of-functional mutations being a susceptibility gene for Moyamoya disease which has prominent tunica media thinning in both intracranial and systemic arteries. Mechanistically, activated FHOD1 upregulated its downstream effector RNF213 independently of its classical pathway of decreasing G-actin/F-actin ratio, transcription, and translation, but dependently on its C-terminus-mediated stabilization of RNF213 protein. FHOD1-RNF213 signaling dramatically promoted collagen-1α/collagen-3α syntheses in VSMCs. Our results discovered a novel signaling axis of FHOD1-RNF213-collagen-1α/collagen-3α and its key role in the pathogenesis of hypertensive TMT.


Asunto(s)
Actinas , Hipertensión , Animales , Ratas , Actinas/metabolismo , Hipertensión/etiología , Hipertrofia , Transducción de Señal/fisiología , Factores de Transcripción , Túnica Media/metabolismo
6.
Opt Express ; 31(8): 12059-12071, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37157373

RESUMEN

Based on the negative curvature structure, we design a graded-index photonic crystal fiber (GI-PCF) supporting the orbital angular momentum (OAM) mode transmission and discuss its optimization strategy. The core of the designed GI-PCF is sandwiched by three-layer inner air-hole arrays with gradually decreasing air-hole radii and a single outer air-hole array, where the inner side of the annular core forms a graded refractive index distribution. All these structures are clad with negative-curvature tubes. By optimizing characteristic structural parameters, including the air-filling fraction of the outer array, the air-hole radii of the inner arrays, and the thickness of the tubes, the GI-PCF can support 42 OAM modes and most of them have a purity greater than 85%. Compared with conventional structures, the present design of GI-PCF has better properties on an overall level, which can stably transmit multiple OAM modes with high mode purity. These results inject new interest in the flexible design of PCF and have potential applications in various fields, including but not limited to the mode division multiplexing system and terabit data transmission.

7.
Opt Express ; 31(21): 35419-35430, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37859274

RESUMEN

Erbium-doped waveguide amplifiers enable the integration of various active functions on a silicon platform. Er3+ can provide the basis for efficient optical amplification of photonic integrated circuits, but the gain is limited by cooperative upconversion leading to doping concentration limitations and insufficient optimization of the waveguide structure. In this paper, an erbium-ytterbium co-doped Al2O3 amplifier has been innovatively implemented on a low loss Si3N4 waveguide by careful design and optimization with the finite difference method. A more accurate and comprehensive theoretical model of erbium-ytterbium co-doping is established, with consideration of upconversions, energy transfer, amplified spontaneous radiation and propagation loss to perform optimization of the high-gain erbium-ytterbium co-doped waveguide amplifier. The optimized waveguide amplifier achieves a small-signal gain of more than 36 dB at 1550 nm under Er3+ concentration of 3 × 1020 cm-3 and Yb3+ concentration of 3 × 1021 cm-3. Endowing Si3N4 photonic integrated circuits with gain can enable the miniaturization of various on-chip based active devices.

8.
Opt Lett ; 48(22): 5947-5950, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37966759

RESUMEN

We demonstrate multiple flatbands and compact localized states (CLSs) in a photonic super-Kagome lattice (SKL) that exhibits coexistence of singular and nonsingular flatbands within its unique band structure. Specifically, we find that the upper two flatbands of an SKL are singular-characterized by singularities due to band touching with their neighboring dispersive bands at the Brillouin zone center. Conversely, the lower three degenerate flatbands are nonsingular and remain spectrally isolated from other dispersive bands. The existence of such two distinct types of flatbands is experimentally demonstrated by observing stable evolution of the CLSs with various geometrical shapes in a laser-written SKL. We also discuss the classification of the flatbands in momentum space, using band-touching singularities of the Bloch wave functions. Furthermore, we validate this classification in real space based on unit cell occupancy of the CLSs in a single SKL plaquette. These results may provide insights for the study of flatband transport, dynamics, and nontrivial topological phenomena in other relevant systems.

9.
Europace ; 25(1): 146-155, 2023 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35942655

RESUMEN

AIMS: Activation mapping of premature atrial complexes (PACs) proves challenging due to interference by mechanical bumping and non-targeted ectopies. This study aims to compare the mapping efficacy, instant success, and long-term recurrence of catheter ablation for PACs with non-pulmonary vein (PV) and non-superior vena cava (SVC) origins between the novel dual-reference approach (DRA) and the routine single-reference approach (SRA) of mapping. METHODS AND RESULTS: Patients with symptomatic, drug-refractory PACs, or frequent residual PACs after atrial tachyarrhythmia ablation were enrolled. During activation mapping, the coronary sinus (CS) catheter was used as the only timing reference in the SRA group. In the DRA group, another catheter, which was spatially separated from the CS catheter, was used as the second reference. The timing difference between the two references was used to discriminate the targeted PACs from the uninterested rhythms. Procedural parameters and long-term recurrence were compared. A total of 188 patients (109 in SRA and 79 in DRA) were enrolled. The baseline characteristics were similar. Compared with the SRA group, the DRA group had less repeated mapping (1.2 ± 0.4 vs. 1.4 ± 0.5, P = 0.004), shorter mapping (15 ± 6 vs. 23 ± 7 min, P < 0.001) and procedural time (119 ± 28 vs. 132 ± 22 min, P = 0.001), similar procedural complication rates (3.6 vs. 3.8%, P > 0.999), higher instant success (96.2 vs. 87.2%, P = 0.039), and lower recurrence rate (15.2 vs. 29.3%, hazard ratio 1.943, P = 0.033) during a 24-month follow-up. CONCLUSION: As a novel strategy, the DRA shortens the procedural time and improves both instant and long-term success of PAC ablation, serving as a promising approach in mapping PACs with non-PV and non-SVC origins.


Asunto(s)
Fibrilación Atrial , Complejos Atriales Prematuros , Ablación por Catéter , Venas Pulmonares , Humanos , Fibrilación Atrial/cirugía , Resultado del Tratamiento , Venas Pulmonares/cirugía , Complejos Atriales Prematuros/diagnóstico , Complejos Atriales Prematuros/cirugía , Ablación por Catéter/efectos adversos , Ablación por Catéter/métodos , Recurrencia
10.
Pacing Clin Electrophysiol ; 46(9): 1035-1048, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37573146

RESUMEN

Transcatheter radiofrequency ablation has been widely introduced for the treatment of tachyarrhythmias. The demand for catheter ablation continues to grow rapidly as the level of recommendation for catheter ablation. Traditional catheter ablation is performed under the guidance of X-rays. X-rays can help display the heart contour and catheter position, but the radiobiological effects caused by ionizing radiation and the occupational injuries worn caused by medical staff wearing heavy protective equipment cannot be ignored. Three-dimensional mapping system and intracardiac echocardiography can provide detailed anatomical and electrical information during cardiac electrophysiological study and ablation procedure, and can also greatly reduce or avoid the use of X-rays. In recent years, fluoroless catheter ablation technique has been well demonstrated for most arrhythmic diseases. Several centers have reported performing procedures in a purposefully designed fluoroless electrophysiology catheterization laboratory (EP Lab) without fixed digital subtraction angiography equipment. In view of the lack of relevant standardized configurations and operating procedures, this expert task force has written this consensus statement in combination with relevant research and experience from China and abroad, with the aim of providing guidance for hospitals (institutions) and physicians intending to build a fluoroless cardiac EP Lab, implement relevant technologies, promote the standardized construction of the fluoroless cardiac EP Lab.


Asunto(s)
Ablación por Catéter , Técnicas Electrofisiológicas Cardíacas , Cirugía Asistida por Computador , Humanos , Electrofisiología Cardíaca , Ablación por Catéter/métodos , Técnicas Electrofisiológicas Cardíacas/métodos , Cirugía Asistida por Computador/métodos , Resultado del Tratamiento
11.
J Electrocardiol ; 81: 85-93, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37647776

RESUMEN

The ECG diagnosis of LVH is predominantly based on the QRS voltage criteria, i.e. the increased QRS complex amplitude in defined leads. The classical ECG diagnostic paradigm postulates that the increased left ventricular mass generates a stronger electrical field, increasing the leftward and posterior QRS forces. These increased forces are reflected in the augmented QRS amplitude in the corresponding leads. However, the clinical observations document increased QRS amplitude only in the minority of patients with LVH. The low sensitivity of voltage criteria has been repeatedly documented. We discuss possible reasons for this shortcoming and proposal of a new paradigm.


Asunto(s)
Electrocardiografía Ambulatoria , Hipertrofia Ventricular Izquierda , Humanos , Hipertrofia Ventricular Izquierda/diagnóstico , Electrocardiografía , Sistema de Conducción Cardíaco
12.
Opt Express ; 30(3): 4381-4391, 2022 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-35209676

RESUMEN

We propose a new kind of reconfigurable topological valley photonic crystal (TVPC), and a novel topological waveguide can be formed by constructing a domain wall between two TVPCs with opposite valley-Chern indices. The topological waveguide mode in the composite TVPC has large group refractive index. A topologically protected coupled waveguide cavity system is then designed by introducing a hexagonal ring cavity at the center of the straight domain wall of a combined TVPC, in which a narrow plasmon induced transparency window rises at 3.8848 GHz with a Q-factor of 1387 and a maximum group refractive index as high as 186. We propose a notch filter with a resonant frequency of 3.8852 GHz and a very high Q-factor of 10224. By changing the refractive index of liquid crystals via an external voltage applied between two parallel metal plates, the filter can be switched between band-pass and band-stop based on the reconfigurable topological interface state.

13.
Curr Opin Cardiol ; 37(1): 74-79, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34857717

RESUMEN

PURPOSE OF REVIEW: Combined atrial fibrillation (AF) ablation and left atrial (LA) appendage (LAA) closure (LAAC) has been practiced for management of both the symptoms and the high stroke risk of AF. The purpose of this review is to review recent evidence regarding the combined procedure. RECENT FINDINGS: Newly acquired long-term data of combined AF ablation and LAAC supplied satisfactory evidence on the safety and efficacy of the combined procedure. Studies also showed LA structural remodeling following combined procedure was mainly affected by sinus rhythm status post catheter ablation, not by LAAC. A cost-effectiveness study revealed that combined procedure was a cost-effective therapeutic option in symptomatic AF patients with high stroke and bleeding risk. Due to recent evidence of high incidences of LAA thrombus formation after LAA electrical isolation (LAAEI) and benefit of LAAC after LAAEI, an extended combined procedure of standard AF ablation plus LAAEI and LAAC was considered as a potential therapeutic option for persistent AF patients with high stroke risk. SUMMARY: In conclusion, combined AF ablation and LAAC serve as a promising option for patients with symptomatic AF and high risk of stroke and/or bleeding.


Asunto(s)
Apéndice Atrial , Fibrilación Atrial , Procedimientos Quirúrgicos Cardíacos , Ablación por Catéter , Accidente Cerebrovascular , Apéndice Atrial/cirugía , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/cirugía , Procedimientos Quirúrgicos Cardíacos/métodos , Ablación por Catéter/métodos , Humanos , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Resultado del Tratamiento
14.
BMC Cardiovasc Disord ; 22(1): 360, 2022 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-35933334

RESUMEN

BACKGROUND: Adaptive cardiac resynchronization therapy (aCRT) is associated with improved clinical outcomes. Left bundle branch area pacing (LBBAP) has shown encouraging results as an alternative option for aCRT. A technique that can be accomplished effectively using LBBAP combined with coronary venous pacing (LOT-aCRT). We aimed to assess the feasibility and outcomes of LOT-aCRT. METHODS: LOT-aCRT, capable of providing two pacing modes, LBBAP alone or LBBAP combined with LV pacing, was attempted in patients with CRT indications. Patients were divided into two groups: those with LBBAP and LV pacing (LOT-aCRT) and those with conventional biventricular pacing (BVP-aCRT). RESULTS: A total of 21 patients were enrolled in the study (10 in the LOT-aCRT group, 11 in the BVP-aCRT group). In the LOT-aCRT group, the QRS duration (QRSd) via BVP was narrowed from 158.0 ± 13.0 ms at baseline to 132.0 ± 4.5 ms (P = 0.019) during the procedure, and further narrowed to 123.0 ± 5.7 ms (P < 0.01) via LBBAP. After the procedure, when LOT-aCRT implanted and worked, QRSd was further changed to 121.0 ± 3.8 ms, but the change was not significant (P > 0.05). In the BVP-aCRT group, BVP resulted in a significant reduction in the QRSd from 176.7 ± 19.7 ms at baseline to 133.3 ± 8.2 ms (P = 0.011). However, compared with LOT-aCRT, BVP has no advantage in reducing QRSd and the difference was statistically significant (P < 0.01). During 9 months of follow-up, patients in both groups showed improvements in the LVEF and NT-proBNP levels (all P < 0.01). However, compared with BVP-aCRT, LOT-aCRT showed more significant changes in these parameters (P < 0.01). CONCLUSIONS: The study demonstrates that LOT-aCRT is clinically feasible in patients with systolic heart failure and LBBB. LOT-aCRT was associated with significant narrowing of the QRSd and improvement in LV function.


Asunto(s)
Terapia de Resincronización Cardíaca , Insuficiencia Cardíaca , Terapia de Resincronización Cardíaca/efectos adversos , Electrocardiografía/métodos , Sistema de Conducción Cardíaco , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/terapia , Humanos , Resultado del Tratamiento , Función Ventricular Izquierda
15.
Echocardiography ; 39(1): 118-121, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34866231

RESUMEN

Prevalence of primary coronary cameral fistula (CCF) is extremely rare, especially for CCF with its drainage channel into the left ventricle (LV). We describe a 45-year-old male patient with giant aneurysm associated with proximal right coronary artery (RCA), and the distal end of RCA draining into the LV through a fistula, which was discovered by echocardiography. Dual-source computer tomography revealed only the CCF-related giant RCA aneurysm. The drainage site of the fistula and the above coexistent abnormality could not be visualized clearly by coronary artery angiography because of deficient contrast medium filling into the aneurysm. The patient underwent surgical resection of the giant aneurysm and occlusion of the fistula in 2015. Finally, the patient accepted another operation to occlude the residual coronary fistula in 2021.


Asunto(s)
Aneurisma Coronario , Fístula , Aneurisma Coronario/cirugía , Angiografía Coronaria/métodos , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/cirugía , Fístula/complicaciones , Fístula/diagnóstico por imagen , Fístula/cirugía , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/cirugía , Humanos , Masculino , Persona de Mediana Edad
16.
Pflugers Arch ; 473(3): 491-506, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33411079

RESUMEN

Apamin-sensitive small-conductance calcium-activated potassium (SK) current (IKAS) plays an important role in cardiac repolarization under a variety of physiological and pathological conditions. The regulation of cardiac IKAS relies on SK channel expression, intracellular Ca2+, and interaction between SK channel and intracellular Ca2+. IKAS activation participates in multiple types of arrhythmias, including atrial fibrillation, ventricular tachyarrhythmias, and automaticity and conduction abnormality. Recently, sex dimorphisms in autonomic control have been noticed in IKAS activation, resulting in sex-differentiated action potential morphology and arrhythmogenesis. This review provides an update on the Ca2+-dependent regulation of cardiac IKAS and the role of IKAS on arrhythmias, with a special focus on sex differences in IKAS activation. We propose that sex dimorphism in autonomic control of IKAS may play a role in J wave syndrome.


Asunto(s)
Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/fisiopatología , Caracteres Sexuales , Canales de Potasio de Pequeña Conductancia Activados por el Calcio/fisiología , Animales , Femenino , Humanos , Masculino
17.
J Cardiovasc Electrophysiol ; 32(10): 2655-2664, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34428342

RESUMEN

OBJECTIVES: To explore the value of detecting the peri-device leak (PDL) and device endothelialization after left atrial appendage closure (LAAC) by cardiac computed tomography (CT) in patients with atrial fibrillation (AF), who underwent Watchman LAAC combined with radiofrequency ablation of atrial fibrillation (AFCA). METHODS: Patients with symptomatic drug-refractory atrial fibrillation at high risk of stroke (CHA2 DS2 -VASc Score ≥ 2), who underwent Watchman LAAC combined with AFCA in our center from March 2017 to December 2018 were enrolled. Maximum diameter of LAA orifice was determined by preoperative CCTA. A standardized view of Watchman device was obtained by postoperative CCTA multiplannar reconstruction to evaluate the PDL and device endothelialization. RESULTS: Approximately 84 patients post successful LAAC and AFCA were enrolled in this study. The satisfactory LAA occlusion rate was 100%. There was no death, bleeding, stroke, and device-related thrombus (DRT) events. At 6-month postprocedure, CCTA images evidenced complete endothelialization in 44 patients (no contrast enhancement in LAA); contrast enhancement in LAA and visible PDL in 33 patients; contrast enhancement in LAA but without PDL in seven patients (incomplete device endothelialization). Maximum diameter of LAA orifice could independently predict the occurrence of PDL (odds ratio, 1.31; 95% confidence interval, 1.11-1.55; p = .002), sensitivity was 69.7% and specificity was 80.4% with the cutoff value of maximum diameter of LAA orifice more than 28.2 mm on predicting PDL. CONCLUSIONS: CCTA is feasible to evaluate PDL and device endothelialization after LAAC. The maximum diameter of LAA orifice derived from CT can independently predict the occurrence of post-LAAC PDL.


Asunto(s)
Apéndice Atrial , Fibrilación Atrial , Ablación por Radiofrecuencia , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/cirugía , Fibrilación Atrial/diagnóstico por imagen , Fibrilación Atrial/cirugía , Angiografía por Tomografía Computarizada , Ecocardiografía Transesofágica , Humanos , Estudios Prospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
18.
Phys Rev Lett ; 124(18): 183901, 2020 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-32441985

RESUMEN

Topological properties of lattices are typically revealed in momentum space using concepts such as the Chern number. Here, we study unconventional loop states, namely, the noncontractible loop states (NLSs) and robust boundary modes, mediated by nontrivial topology in real space. While such states play a key role in understanding fundamental physics of flatband systems, their experimental observation has been hampered because of the challenge in realizing desired boundary conditions. Using a laser-writing technique, we optically establish photonic kagome lattices with both an open boundary by properly truncating the lattice, and a periodic boundary by shaping the lattice into a Corbino geometry. We thereby demonstrate the robust boundary modes winding around the entire edge of the open lattice and, more directly, the NLSs winding in a closed loop akin to that in a torus. We prove that the NLSs due to real-space topology persist in ideal Corbino-shaped kagome lattices of arbitrary size. Our results could be of great importance for our understanding of the singular flatbands and the intriguing physics phenomenon applicable for strongly interacting systems.

19.
BMC Cancer ; 20(1): 13, 2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-31906980

RESUMEN

BACKGROUND: Primary angiosarcomas of the right atrium are extremely rare, often resulted in missed diagnosis or misdiagnosis with routine examination tools. These malignant cardiac tumors are highly aggressive with generally poor prognosis. Surgical excision is the mainstay of treatment as it is essentially not responsive to current regimens of chemoradiotherapy. CASE PRESENTATION: Herein, we describe a patient who initially presented with paroxysmal atrial fibrillation and was subsequently treated with radiofrequency catheter ablation (RFCA). Prior to RFCA, an initial transesophageal echocardiography revealed a local thickening of the intratrial septum. Three months later, she was hospitalized with progressive dyspnea and massive pericardial effusion. A large immobile, non-pedunculated mass, occupying almost half of the right atrium was detected by transthoracic and transesophageal echocardiogram. Multimodality cardiac imaging was useful in further characterizing this mass, which was ultimately diagnosed as an angiosarcoma based upon biopsy results. The growth rate was extremely rapid following RFCA, and patient underwent surgical excision. After discharge, the angiosarcoma recurred and patient survived for 7 months from the first episode of tamponade. CONCLUSIONS: Primary cardiac angiosarcoma of the right atrium can easily be mistaken for structural anomalies in its early stages, losing the opportunity for initiating earlier treatments to improve potential patient outcomes. The correct diagnosis of this rare case relied on the comprehensive utilization of multimodal imaging techniques including biopsy.


Asunto(s)
Ablación por Catéter , Atrios Cardíacos , Neoplasias Cardíacas/diagnóstico , Hemangiosarcoma/diagnóstico , Diagnóstico Erróneo , Fibrilación Atrial/diagnóstico , Disnea/diagnóstico , Disnea/etiología , Resultado Fatal , Femenino , Atrios Cardíacos/patología , Neoplasias Cardíacas/diagnóstico por imagen , Neoplasias Cardíacas/patología , Neoplasias Cardíacas/cirugía , Hemangiosarcoma/diagnóstico por imagen , Hemangiosarcoma/patología , Hemangiosarcoma/cirugía , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Derrame Pericárdico/diagnóstico , Tomografía de Emisión de Positrones
20.
J Interv Cardiol ; 2020: 8615410, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32669982

RESUMEN

AIM: The feasibility and safety of performing the combined procedure of catheter ablation (CA) and left atrial appendage closure (LAAC) for atrial fibrillation (AF) have been reported by observational studies without controls. The aim of this study was to compare the procedural and long-term outcomes of combined procedures with isolated CA or LAAC. METHODS AND RESULTS: This study included patients who underwent combined CA and LAAC (combined group), CA alone (CA-only group), or LAAC alone (LAAC-only group). Propensity score matching was used to select controls from the CA-only and LAAC-only groups. Each group contained 76 subjects. The procedures were successfully performed in all the patients. Procedure-related complications of the combined group included one pericardial effusion and two groin haematomas, which did not differ significantly with those of the CA-only group (3.9% vs. 2.6%, P=0.650) or the LAAC-only group (3.9% vs. 2.6%, P=0.650), respectively. The AF-free rate of the combined group was comparable with that of the CA-only group after a mean of 2 years follow-up (67.1% vs. 69.7%, P=0.727). Compared with the LAAC-only group, the combined group achieved similar complete occlusion rate at implant (94.7% vs. 93.4%) and at 45 days (82.9% vs. 85.5%). At the end of follow-up, ischemic stroke and bleeding events of the combined group were low (3.9%) and were comparable with those of the CA-only group (5.3%) and the LAAC-only group (2.6%). CONCLUSIONS: The combination of AF-CA and LAAC is safe and efficacious compared with single procedures alone.


Asunto(s)
Apéndice Atrial/cirugía , Fibrilación Atrial/cirugía , Ablación por Catéter , Complicaciones Posoperatorias , Implantación de Prótesis , Dispositivo Oclusor Septal , Anciano , Fibrilación Atrial/complicaciones , Estudios de Casos y Controles , Ablación por Catéter/efectos adversos , Ablación por Catéter/métodos , Femenino , Humanos , Masculino , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/etiología , Implantación de Prótesis/efectos adversos , Implantación de Prótesis/instrumentación , Implantación de Prótesis/métodos , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Resultado del Tratamiento
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