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Based on the density functional theory and the Monte Carlo Simulation (MCS), the structural, the electronic and the magnetic properties of Sr 2 TiMoO 6 double perovskite have been studied with (GGA), (GGA + U) and (GGA + U + SOC) approaches. The lattice parameter, the band structure and the electronic densities of states have been analyzed. Furthermore, the results show a half-metallic behavior of the compound with (GGA + U) . By the energy calculation, Sr 2 TiMoO 6 oxide shows an antiferromagnetic ordering. The exchange coupling of Sr 2 TiMoO 6 has been also computed in order to investigate the magnetic properties by using MCS in the framework of the Ising model. Interesting phenomena have been obtained such as the first-order transitions and multiple hysteresis loops. These results make Sr 2 TiMoO 6 a promising candidate for spintronic applications. [ABSTRACT FROM AUTHOR]

Based on the density functional theory and the Monte Carlo Simulation (MCS), the structural, the electronic and the magnetic properties of Sr 2 TiMoO 6 double perovskite have been studied with (GGA), (GGA + U) and (GGA + U + SOC) approaches. The lattice parameter, the band structure and the electronic densities of states have been analyzed. Furthermore, the results show a half-metallic behavior of the compound with (GGA + U) . By the energy calculation, Sr 2 TiMoO 6 oxide shows an antiferromagnetic ordering. The exchange coupling of Sr 2 TiMoO 6 has been also computed in order to investigate the magnetic properties by using MCS in the framework of the Ising model. Interesting phenomena have been obtained such as the first-order transitions and multiple hysteresis loops. These results make Sr 2 TiMoO 6 a promising candidate for spintronic applications. [ABSTRACT FROM AUTHOR]

Wetland systems in arid countries can serve as a rich source of biodiversity and an ideal location to study invertebrate species diversity. Two study sites have been delimited in the Chott Zahrez Gharbi characterised by a semi-arid climate, a cold winter and a vegetation cover dominated by halophile species. One site is located north of Zahrez in the Hassi Bahbah region and the second one south of Zahrez in the Zaâfrane region. A comparative study of the Arthropoda communities, focused on Coleoptera and Araneae, was conducted during one year, using pitfall traps (Barber traps) monthly. In total 7344 individuals, belonging to 215 species, including 80 species of Coleoptera and 38 species of Araneae were collected. The Shannon-Weaver diversity index (H') varies between 0.41 and 2.95 bits. The results showed that Hassi Bahbah is richer and more diverse than Zaâfrane. The humidity and the organic matter are clearly higher in Hassi Bahbah than in Zaâfrane. A detrended correspondence analysis (DCA) showed a clear distinction of the species' groups between the two study areas. [ABSTRACT FROM AUTHOR]

The conception and modeling of a photovoltaic cell are done by combining the density functional theory (DFT) and solar cell capacitance simulator (SCAPS). The search for new lead-free halide semiconductor perovskite materials with an appropriate band gap, which can be used as good absorbers of solar radiation in the studied photovoltaic cell, is realized by substituting a percentage of sodium (Na) with potassium (K) and sulphur (S) in the double perovskite Cs 2 NaCrCl 6. The study also focuses on the choice of the best materials for the electron transport layer (ETL) and the hole transport one (HTL) as well as the thickness of the perovskite semiconductor materials Cs 2 Na 1− x X x CrCl 6 (X = S and K). The results reveal that Cu 2 O and WS 2 are suitable materials for HTL and ETL layers, respectively. The optimal thickness of the perovskite semiconductor is equal to 2 μm. Under optimized conditions, the photovoltaic device power conversion efficiency (η) equals 15.01 % and 20.01 % by using Cs 2 Na 0.5 K 0.5 CrCl 6 with E g = 1.8 eV and Cs 2 NaCrCl 6 with E g = 1.6 eV as active layer, respectively. Therefore, the obtained photovoltaic cell model is (Cu 2 O / Cs 2 NaCrCl 6 / WS 2 /FTO), with an efficiency of η = 20.01 %. • New semiconductor perovskite Cs 2 Na 1− x X x CrCl 6 (X = S and K) with appropriate band gap have been found. • Studies of ETL, HTL and semiconductor perovskite thickness have been done. • The efficiency of designed photovoltaic cell (Cu 2 O ∕ Cs 2 NaCrCl 6 ∕ WS 2 ∕FTO) is η = 20.01 %. • Conception and modeling of photovoltaic cell is done by combining DFT and SCAPS. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bi 2 NiCrO 6 is synthesized by the sol–gel method. • Bi 2 NiCrO 6 shows a cubic structure with an Fm3m space group. • Bi 2 NiCrO 6 is a metallic and ferromagnetic material (μ=1.17μB). • Bi 2 NiCrO 6 is a good candidate for spintronic application. In this work, the experimental and theoretical studies of Bi 2 NiCrO 6 double perovskite material have been performed. The synthesis of Bi 2 NiCrO 6 is made by sol–gel method. The X-ray diffraction (XRD) characterisation of the material reveals that the double perovskite adopts a cubic structure (a = 7.75 Å) with Fm3m space group. Based on the Density Functional Theory (DFT) with spin polarized calculations, the electronic and magnetic properties have been investigated. From the total electronic density of states and the electronic band structure analysis, it is found that Bi 2 NiCrO 6 exhibits a metallic behavior. It is also found that the studied compound is ferromagnetic material with a total magnetic moment 1.17 μ B . The results show that Bi 2 NiCrO 6 material is a good candidate for using in devices that requires multifunctional operations including spintronic. [ABSTRACT FROM AUTHOR]

[Display omitted] • DFT has been used to study the optic and electronic properties of Cs 2 AgBiX 6 (X = I ; Br ; Cl and F). • The studied compounds exhibit a semiconductor behavior. • The fluorine based perovskite is the least absorbent. • Bromine and Chlorine based perovskites are very interesting for the photovoltaic and optoelectronic. Lead free halide double perovskites are widely studied for their semiconducting behavior which allows them to be used as absorbing materials in solar cells and optoelectronic applications. In this paper, in order to look for perovskite materials with appropriate absorption and band gap, our aim is to study the electronic and optical properties of Cs 2 AgBiX 6 (X = I , Br , Cl and F) by using the density functional theory (DFT) with generalized gradient approximation (GGA). The found results show that the investigated halide compounds present a semiconductor features which absorb in a long wavelength range. Furthermore, iodine based halide perovskite exhibits a negative values of the dielectric function real part which correspond to a high photon reflection, besides the fluorine one is the least absorbent material. From the obtained results, our work confirm that, bromine and chlorine based double perovskites are very interesting for the photovoltaic and optoelectronic applications. [ABSTRACT FROM AUTHOR]

Environmental friendly double perovskite Sr 2 TiMoO 6 has been studied by using the density functional theory with generalized gradient approximation (GGA+U) approaches, and the Monte Carlo simulation in the framework of Ising model. The parameter of the unit cell has been optimized. The value of the crystal field and the exchange coupling have been estimated from the partial electronic density of states and the energy calculations, respectively. The magnetic properties and the magnetocaloric effect of the compound have been also studied. The Relative cooling power has been performed. It is found that Sr 2 TiMoO 6 is an interesting material for the magnetic refrigeration applications. • DFT and Monte Carlo simulation in the framework of Ising model have been performed. • Magnetocaloric effect in double perovskite Sr 2 TiMoO 6 has been studied. • Magnetic entropy change and relative cooling power have been calculated. • Sr 2 TiMoO 6 is an interesting material for the magnetic refrigeration applications. [ABSTRACT FROM AUTHOR]

As crucial stages in the plant ontogeny, germination and seedling establishment under adverse conditions greatly determine staple crop growth and productivity. In the context of green technologies aiming to improve crop yield, seed priming is emerging as an effective approach to enhance seed vigor and germination performance under salt stress. In this study, we assess the efficiency of seed priming with indole-3-acetic acid (IAA) in mitigating the adverse effects of salt stress on maize (Zea mays L.) seedlings during germination and early seedling stages. In unprimed seeds, salt stress reduced germination indices, and seedling (both radicle and coleoptile) growth, together with decreased tissue hydration. However, seed priming using IAA significantly improved maize salt response, as reflected by the increased seed germination dynamics, early seedling establishment, and water status. Besides, seedlings from IAA-primed seeds showed a higher activity of α-amylase, resulting in increased sugar contents in roots and coleoptiles of salt-stressed plants. Further, IAA-seed priming stimulated the accumulation of endogenous IAA in salt-stressed seedlings, in concomitance with a significant effect on reactive oxygen species detoxification and lipid peroxidation prevention. Indeed, our data revealed increased antioxidant enzyme activities, differentially regulated in roots and coleoptiles, leading to increased activities of the antioxidant enzymes (SOD, CAT and GPX). In summary, data gained from this study further highlight the potential of IAA in modulating early interactions between multiple signaling pathways in the seed, endowing maize seedlings with enhanced potential and sustained tolerance to subsequent salt stress., (© 2024. The Author(s).)

Plants are highly sensitive to various environmental stresses, which can hinder their growth and reduce yields. In this study, we investigated the potential of seed priming with salicylic acid (SA), gibberellic acid (GA 3 ), and sodium chloride (NaCl) to mitigate the adverse effects of salinity stress in Hordeum vulgare at the germination and early seedling stages. Exposing H. vulgare seeds to salt stress reduced the final germination percentage and seedling shoot and root growth. Interestingly, all seed treatments significantly improved salt-induced responses, with GA 3 being more effective in terms of germination performance, plant growth, and photosynthesis. SA priming exhibited promising effects on antioxidant defense mechanisms, proline, sugar, and ascorbic acid production. Notably, SA priming also suppressed reactive oxygen species accumulation and prevented lipid peroxidation. These findings highlight the ability of SA to manage crosstalk within the seed, coordinating many regulatory processes to support plant adaptation to salinity stress.

Background: CLOSE-guided pulmonary vein isolation (PVI) is based on contiguous and optimized (Ablation Index-guided) radiofrequency lesions. The efficacy of CLOSE-guided PVI in persistent atrial fibrillation (AF) treatment has been poorly evaluated., Methods: In two centers, 50 patients eligible for persistent AF ablation underwent CLOSE-guided PVI (Ablation Index ≥ 450 at the anterior wall, ≥300 at posterior wall, intertag distance ≤ 6 mm). If PVI failed to restore sinus rhythm (SR), electrical cardioversion (ECV) was performed. Atrial substrate modification (ASM) was performed only if PVI and ECV failed to restore SR. Recurrence was defined as any recorded episode of AF, atrial tachycardia (AT) or atrial flutter (AFL) > 30 s on Holter electrocardiographs at 3, 6 and 12 months., Results: From the 50 patients (64 ± 10 years, 14% long-standing persistent AF), SR was restored by ECV in 34 patients (68%) 56 ± 38 days prior to ablation. On the day of ablation, 42 patients (84%) were on class I-III anti-arrhythmic drug therapy (ADT) and the rhythm was AF in 23/50 patients. PVI was achieved in all patients; after PVI, ECV was required in 21 patients and ASM in 1 patient. The mean procedure time, radiofrequency time and fluoroscopy time were 141 ± 33 min, 23 ± 7 min and 7 ± 6 min, respectively. At 12 months, single-procedure freedom from AF/AT/AFL was 80%, with 19 patients (38%) receiving class I-III ADT., Conclusions: In a population of patients with persistent AF monitored with intermittent cardiac rhythm recordings, CLOSE-guided PVI resulted in high single-procedure arrhythmia-free survival at 1 year. Future large-scale studies involving continuous cardiac monitoring are necessary.

HIV-2 infection is characterized by low viremia and slow disease progression as compared to HIV-1 infection. Circulating CD14 ++ CD16 + monocytes were found to accumulate and CD11c + conventional dendritic cells (cDC) to be depleted in a Portuguese cohort of people living with HIV-2 (PLWHIV-2), compared to blood bank healthy donors (HD). We studied more precisely classical monocytes; CD16 + inflammatory (intermediate, non-classical and slan + monocytes, known to accumulate during viremic HIV-1 infection); cDC1, important for cross-presentation, and cDC2, both depleted during HIV-1 infection. We analyzed by flow cytometry these PBMC subsets from Paris area residents: 29 asymptomatic, untreated PLWHIV-2 from the IMMUNOVIR-2 study, part of the ANRS-CO5 HIV-2 cohort: 19 long-term non-progressors (LTNP; infection ≥8 years, undetectable viral load, stable CD4 counts≥500/μL; 17 of West-African origin -WA), and 10 non-LTNP (P; progressive infection; 9 WA); and 30 age-and sex-matched controls: 16 blood bank HD with unknown geographical origin, and 10 HD of WA origin (GeoHD). We measured plasma bacterial translocation markers by ELISA. Non-classical monocyte counts were higher in GeoHD than in HD (54 vs. 32 cells/μL, p = 0.0002). Slan + monocyte counts were twice as high in GeoHD than in HD (WA: 28 vs. 13 cells/μL, p = 0.0002). Thus cell counts were compared only between participants of WA origin. They were similar in LTNP, P and GeoHD, indicating that there were no HIV-2 related differences. cDC counts did not show major differences between the groups. Interestingly, inflammatory monocyte counts correlated with plasma sCD14 and LBP only in PLWHIV-2, especially LTNP, and not in GeoHD. In conclusion, in LTNP PLWHIV-2, inflammatory monocyte counts correlated with LBP or sCD14 plasma levels, indicating a potential innate immune response to subclinical bacterial translocation. As GeoHD had higher inflammatory monocyte counts than HD, our data also show that specific controls are important to refine innate immunity studies., (Copyright © 2020 Iannetta, Isnard, Manuzak, Guillerme, Notin, Bailly, Andrieu, Amraoui, Vimeux, Figueiredo, Charmeteau-de Muylder, Vaton, Hatton, Samri, Autran, Thiébaut, Chaghil, Glohi, Charpentier, Descamps, Brun-Vézinet, Matheron, Cheynier and Hosmalin.)

The endoplasmic reticulum (ER) is the site for Zika virus (ZIKV) replication and is central to the cytopathic effects observed in infected cells. ZIKV induces the formation of ER-derived large cytoplasmic vacuoles followed by "implosive" cell death. Little is known about the nature of the ER factors that regulate flavivirus replication. Atlastins (ATL1, -2, and -3) are dynamin-related GTPases that control the structure and the dynamics of the ER membrane. We show here that ZIKV replication is significantly decreased in the absence of ATL proteins. The appearance of infected cells is delayed, the levels of intracellular viral proteins and released virus are reduced, and the cytopathic effects are strongly impaired. We further show that ATL3 is recruited to viral replication sites and interacts with the nonstructural viral proteins NS2A and NS2B3. Thus, proteins that shape and maintain the ER tubular network ensure efficient ZIKV replication. IMPORTANCE Zika virus (ZIKV) is an emerging virus associated with Guillain-Barré syndrome, and fetal microcephaly as well as other neurological complications. There is no vaccine or specific antiviral treatment against ZIKV. We found that endoplasmic reticulum (ER)-shaping atlastin proteins (ATL1, -2, and -3), which induce ER membrane fusion, facilitate ZIKV replication. We show that ATL3 is recruited to the viral replication site and colocalize with the viral proteins NS2A and NS2B3. The results provide insights into host factors used by ZIKV to enhance its replication., (Copyright © 2019 American Society for Microbiology.)

Background: Anatomic macroreentrant atrial tachycardias (MATs) are conventionally reported to depend on the cavotricuspid isthmus, the mitral isthmus, or the left atrial roof, and are commonly seen following catheter ablation for atrial fibrillation., Objectives: To define the precise circuits of anatomic MAT with ultrahigh-resolution mapping., Methods: In 57 patients (mean age, 62 years; 10 female) who developed ≥1 anatomic MAT, we analyzed 88 MAT circuits including 16 peritricuspid, 42 perimitral, and 30 roof-dependent circuits, using high-density mapping and entrainment., Results: Of 16 peritricuspid atrial tachycardias (ATs), 8 (50.0%) showed a circuit not limited to the tricuspid annulus. However, cavotricuspid isthmus ablation terminated the tachycardia in all patients. Similarly, 26 of 42 perimitral ATs (61.9%) showed a circuit not limited to the mitral annulus, and a low-voltage zone <0.1 mV around the mitral annulus was associated with nontypical perimitral ATs (P < .0001). The practical isthmus was not in the mitral isthmus in 13 of these 26 perimitral ATs (50%). Finally, 22 of 30 roof-dependent ATs (73.3%) had a circuit not rotating around both pairs of pulmonary veins. Brief assessment of the activation direction on the posterior wall in relation to that on the septal, anterior, and lateral wall helped deduce the circuit of roof-dependent AT in 27 of 30 (90.0%). Practical isthmus was not in the roof in 8 of 22 (36.4%). Practical isthmuses mapped with the system were significantly shorter than the usual anatomic isthmuses (16.1 ± 8.2 mm vs 33.7 ± 10.4 mm) (P < .0001)., Conclusions: High-density mapping successfully identified the precise circuits and the practical isthmus of anatomic MATs in patients with prior atrial fibrillation ablation., (Copyright © 2017 Heart Rhythm Society. All rights reserved.)

Introduction: It is largely believed that atrial tachycardias (ATs) encountered during ablation of persistent atrial fibrillation (PsAF) are a byproduct of ablative lesions. We aimed to explore the alternative hypothesis that they may be a priori drivers of AF remaining masked until other AF sources are reduced or eliminated., Methods and Results: Radiofrequency ablation of fibrillatory drivers mapped by electrocardiographic imaging (ECGI; ECVUE™, Cardioinsight Technologies, Cleveland, OH, USA) terminated PsAF in 198 (73%) out of 270 patients (61 ± 10 years, 9 ± 9 m). Two hundred and six ATs in 158 patients were subsequently mapped. Their anatomic relationship to the fibrillatory drivers prospectively identified by ECGI was then established. There were 26 (13%), 52 (25%), and 128 (62%) focal, localized, and macrore-entrant ATs, respectively. In focal/localized re-entrant ATs, 64 (82%) were terminated within an AF-driver region, in which 26 (81%) among 32 focal/localized ATs analyzed with 3-D-mapping system merged to driver map occurred from AF-driver regions in 1.0 ± 1.0 cm distance from the driver core. Importantly, there was no attempt at ablation of the associated AF-driver region in 25 of 64 (39%) of focal/localized re-entrant ATs. The sites of ATs origin generally had low-voltage, fractionated, and long-duration electrograms in AF. All but two focal/localized re-entrant ATs were successfully ablated., Conclusion: The majority of post-AF-ablation focal and localized re-entrant ATs originate from the region of prospectively established AF-driver regions. A third of these are localized to regions not subsequently submitted to ablation. These data suggest that many ATs exist, although not necessarily manifest independently, prior to ablation. They may have a role in the maintenance of PsAF in these individuals., (© 2017 Wiley Periodicals, Inc.)

Background: The significance of fractionated electrograms (EGMs) is object of debate, with multiple mechanisms described., Objective: Using Rhythmia, a high-density mapping system, we sought to investigate the relationship between specific electrophysiological phenomena and EGM characteristics at those sites., Methods: Twenty-five consecutive patients underwent high-density atrial mapping during atrial tachycardias. Bipolar EGMs were recorded with a 64-electrode basket catheter. The following atrial phenomena were identified: slow conduction (SC) areas, lines of block (LB), wavefront collisions (WFC), pivot sites (PS), and gaps. EGMs collected at these predefined areas were analyzed in terms of amplitude, duration, and morphology., Results: Twenty-five atrial maps with 195 sites of interest (1755 EGMs) were object of our analysis. Thirty-five percent were sites of SC: fractionation had low amplitude (0.16 ± 0.07 mV) and long duration (87.8 ± 10.7 ms); wavefront collisions were seen in 38% of sites with EGMs shorter in duration (46.5 ± 4.5 ms) and higher in voltage (0.58 ± 0.13 mV); 17% were lines of block, never responsible for fractionation (0.13 ± 0.05 mV; 122.4 ms ± 24.8 ms); 9% were PS with a high degree of fractionation (0.55 ± 0.15 mV; 85.8 ± 7.9 ms). Two gaps were identified (1%) with a low degree of fractionation., Conclusion: Specific EGM characteristics in atrial tachycardia can be reproducibly linked to electrophysiological mechanisms. High-voltage and short-duration EGMs are associated with collision sites and PS that are unlikely to form critical sites for ablation; long-duration, low-voltage EGMs are associated with SC. However, not all SC regions will lie within the critical circuit and identification by only EGM characteristics cannot guide ablation., (Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Objectives: This study sought to assess the relationship between fibrosis and re-entrant activity in persistent atrial fibrillation (AF)., Background: The mechanisms involved in sustaining re-entrant activity during AF are poorly understood., Methods: Forty-one patients with persistent AF (age 56 ± 12 years; 6 women) were evaluated. High-resolution electrocardiographic imaging (ECGI) was performed during AF by using a 252-chest electrode array, and phase mapping was applied to locate re-entrant activity. Sites of high re-entrant activity were defined as re-entrant regions. Late gadolinium-enhanced (LGE) cardiac magnetic resonance (CMR) was performed at 1.25 × 1.25 × 2.5 mm resolution to characterize atrial fibrosis and measure atrial volumes. The relationship between LGE burden and the number of re-entrant regions was analyzed. Local LGE density was computed and characterized at re-entrant sites. All patients underwent catheter ablation targeting re-entrant regions, the procedural endpoint being AF termination. Clinical, CMR, and ECGI predictors of acute procedural success were then analyzed., Results: Left atrial (LA) LGE burden was 22.1 ± 5.9% of the wall, and LA volume was 74 ± 21 ml/m 2 . The number of re-entrant regions was 4.3 ± 1.7 per patient. LA LGE imaging was significantly associated with the number of re-entrant regions (R = 0.52, p = 0.001), LA volume (R = 0.62, p < 0.0001), and AF duration (R = 0.54, p = 0.0007). Regional analysis demonstrated a clustering of re-entrant activity at LGE borders. Areas with high re-entrant activity showed higher local LGE density as compared with the remaining atrial areas (p < 0.0001). Failure to achieve AF termination during ablation was associated with higher LA LGE burden (p < 0.001), higher number of re-entrant regions (p < 0.001), and longer AF duration (p = 0.008)., Conclusions: The number of re-entrant regions during AF relates to the extent of LGE on CMR, with the location of these regions clustering to LGE areas. These characteristics affect procedural outcomes of ablation.

Background: Trials using echocardiographic mechanical dyssynchrony (MD) parameters in narrow QRS patients have shown a negative response to CRT. We hypothesized MD in these patients may relate to myocardial scar rather than electrical dyssynchrony., Methods: We determined the prevalence of cardiac magnetic resonance (CMR) derived measures of MD in 130 systolic heart failure patients with both broad (≥ 130 ms - BQRS) and narrow QRS duration (< 130 ms - NQRS). We assessed whether late gadolinium enhancement derived scar might explain the presence of MD amongst narrow QRS patients. Dyssynchrony was calculated on the basis of a systolic dyssynchrony index (SDI)., Results: Fifty-nine patients (45%) had a NQRS and the remaining had QRS ≥ 130 ms (BQRS group). 25% of NQRS patients had MD based on SDI. In all narrow and broad QRS patients with MD there was a significantly lower scar volume than those without MD (7.4 ± 10.5% vs 13.7 ± 13.3% vs. p < 0.01). This was the case in the BQRS group with a significantly lower scar burden in patients with MD (5.0 ± 7.7% vs 15.4 ± 15.6%, p < 0.01). Notably in the NQRS group this difference was absent with an equal scar burden in patients with MD 13.3 ± 13.9% and without MD 12.5 ± 11%, p = 0.92., Conclusions: 25% of patients with systolic heart failure and a NQRS (< 130 ms) have CMR derived mechanical dyssynchrony. Our findings suggest MD in this group may be secondary to myocardial scar rather than electrical dyssynchrony and therefore not amenable to correction by CRT. This may give insight into non-response and potential harm from CRT in this group.

The DNA-mediated innate immune response underpins anti-microbial defenses and certain autoimmune diseases. Here we used immunoprecipitation, mass spectrometry, and RNA sequencing to identify a ribonuclear complex built around HEXIM1 and the long non-coding RNA NEAT1 that we dubbed the HEXIM1-DNA-PK-paraspeckle components-ribonucleoprotein complex (HDP-RNP). The HDP-RNP contains DNA-PK subunits (DNAPKc, Ku70, and Ku80) and paraspeckle proteins (SFPQ, NONO, PSPC1, RBM14, and MATRIN3). We show that binding of HEXIM1 to NEAT1 is required for its assembly. We further demonstrate that the HDP-RNP is required for the innate immune response to foreign DNA, through the cGAS-STING-IRF3 pathway. The HDP-RNP interacts with cGAS and its partner PQBP1, and their interaction is remodeled by foreign DNA. Remodeling leads to the release of paraspeckle proteins, recruitment of STING, and activation of DNAPKc and IRF3. Our study establishes the HDP-RNP as a key nuclear regulator of DNA-mediated activation of innate immune response through the cGAS-STING pathway., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The cytopathic effects of Zika virus (ZIKV) are poorly characterized. Innate immunity controls ZIKV infection and disease in most infected patients through mechanisms that remain to be understood. Here, we studied the morphological cellular changes induced by ZIKV and addressed the role of interferon-induced transmembrane proteins (IFITM), a family of broad-spectrum antiviral factors, during viral replication. We report that ZIKV induces massive vacuolization followed by "implosive" cell death in human epithelial cells, primary skin fibroblasts and astrocytes, a phenomenon which is exacerbated when IFITM3 levels are low. It is reminiscent of paraptosis, a caspase-independent, non-apoptotic form of cell death associated with the formation of large cytoplasmic vacuoles. We further show that ZIKV-induced vacuoles are derived from the endoplasmic reticulum (ER) and dependent on the PI3K/Akt signaling axis. Inhibiting the Sec61 ER translocon in ZIKV-infected cells blocked vacuole formation and viral production. Our results provide mechanistic insight behind the ZIKV-induced cytopathic effect and indicate that IFITM3, by acting as a gatekeeper for incoming virus, restricts virus takeover of the ER and subsequent cell death., (© 2017 Institut Pasteur.)

Aims: Cardiac perforations caused by pacemaker or implantable cardioverter-defibrillator (ICD) leads are uncommon but potentially fatal events. The optimal approach to such cases is unclear. The aim of this study was to identify the optimal imaging modality and management strategy for cardiac perforation., Methods and Results: All patients presenting to a single institution with cardiac perforation >24 h since implant between 2011 and 2015 were identified retrospectively. Assessment of the diagnostic performance of pre-extraction chest radiography, transthoracic echocardiography (TTE), and computed tomography (CT) was carried out by blinded review. The method of lead extraction and any associated complications were examined. Eighteen cases of cardiac perforation were identified from 426 lead extraction procedures. Sixteen patients had abnormal electrical parameters at device interrogation. In all cases, the perforating lead was an active fixation model, and in four cases, this was an ICD coil. The accuracy of CT imaging for the diagnosis of cardiac perforation was 92.9%, with sensitivity and specificity of 100 and 85.7%, respectively. This was superior to both TTE (accuracy 62.7%, sensitivity and specificity 41.2 and 84.2%, respectively) and chest radiography (accuracy 61.1%, sensitivity and specificity 27.7 and 94.4%, respectively). Transvenous lead extraction (TLE) was performed in 17 patients, and a hybrid surgical approach in 1 patient. Of those who underwent TLE, there was 100% complete procedural success as per Heart Rhythm Society definitions., Conclusion: In the setting of cardiac perforation, CT is the imaging modality of choice. Transvenous lead extraction can be recommended as a safe, efficacious, and versatile intervention., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.)

Background: In contrast to patients with left bundle branch block (LBBB), heart failure patients with narrow QRS and nonspecific intraventricular conduction delay (NICD) display a relatively limited response to cardiac resynchronization therapy. We sought to compare left ventricular (LV) activation patterns in heart failure patients with narrow QRS and NICD to patients with LBBB using high-density electroanatomic activation maps., Methods and Results: Fifty-two heart failure patients (narrow QRS [n=18], LBBB [n=11], NICD [n=23]) underwent 3-dimensional electroanatomic mapping with a high density of mapping points (387±349 LV). Adjunctive scar imaging was available in 37 (71%) patients and was analyzed in relation to activation maps. LBBB patients typically demonstrated (1) a single LV breakthrough at the septum (38±15 ms post-QRS onset); (2) prolonged right-to-left transseptal activation with absence of direct LV Purkinje activity; (3) homogeneous propagation within the LV cavity; and (4) latest activation at the basal lateral LV. In comparison, both NICD and narrow QRS patients demonstrated (1) multiple LV breakthroughs along the posterior or anterior fascicles: narrow QRS versus LBBB, 5±2 versus 1±1; P =0.0004; NICD versus LBBB, 4±2 versus 1±1; P =0.001); (2) evidence of early/pre-QRS LV electrograms with Purkinje potentials; (3) rapid propagation in narrow QRS patients and more heterogeneous propagation in NICD patients; and (4) presence of limited areas of late activation associated with LV scar with high interindividual heterogeneity., Conclusions: In contrast to LBBB patients, narrow QRS and NICD patients are characterized by distinct mechanisms of LV activation, which may predict poor response to cardiac resynchronization therapy., (© 2017 American Heart Association, Inc.)

Background: The underlying mechanisms sustaining human persistent atrial fibrillation (PsAF) is poorly understood., Objectives: This study sought to investigate the complexity and distribution of AF drivers in PsAF of varying durations., Methods: Of 135 consecutive patients with PsAF, 105 patients referred for de novo ablation of PsAF were prospectively recruited. Patients were divided into 3 groups according to AF duration: PsAF presenting in sinus rhythm (AF induced), PsAF <12 months, and PsAF >12 months. Patients wore a 252-electrode vest for body surface mapping. Localized drivers (re-entrant or focal) were identified using phase-mapping algorithms., Results: In this patient cohort, the most prominent re-entrant driver regions included the pulmonary vein (PV) regions and inferoposterior left atrial wall. Focal drivers were observed in 1 or both PV regions in 75% of patients. Comparing between the 3 groups, with longer AF duration AF complexity increased, reflected by increased number of re-entrant rotations (p < 0.05), number of re-entrant rotations and focal events (p < 0.05), and number of regions harboring re-entrant (p < 0.01) and focal (p < 0.05) drivers. With increased AF duration, a higher proportion of patients had multiple extra-PV driver regions, specifically in the inferoposterior left atrium (p < 0.01), superior right atrium (p < 0.05), and inferior right atrium (p < 0.05). Procedural AF termination was achieved in 70% of patients, but decreased with longer AF duration., Conclusions: The complexity of AF drivers increases with prolonged AF duration. Re-entrant and focal drivers are predominantly located in the PV antral and adjacent regions. However, with longer AF duration, multiple drivers are distributed at extra-PV sites. AF termination rate declines as patients progress to longstanding PsAF, underscoring the importance of early intervention., (Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: Scar-related ventricular tachycardia (VT) arises from specific substrate according to etiology., Objective: The purpose of this study was to evaluate the relationship between wall thinning (WT) on multidetector computed tomography (MDCT) and local abnormal ventricular activity (LAVA) in patients with ischemic cardiomyopathy (ICM), postmyocarditis (PMC), and dilated cardiomyopathy (DCM)., Methods: Forty-two patients (40 male, age 58 ± 13 years, 22 ICM, 11 PMC, 9 DCM) underwent MDCT before a combined endo-/epicardial VT ablation procedure. WT (<5 mm) and severe wall thinning (SWT) (<2 mm) area on MDCT were compared to the prevalence of endo-/epicardial LAVA during sinus rhythm., Results: WT and SWT were found on MDCT in 36 (86%) and 20 (48%) with 42 ± 37 cm 2 and 26 ± 24 cm 2 , respectively. SWT was frequently detected in ICM (ICM 77% vs PMC 27% vs DCM 0%, P <.001). LAVA were frequently observed on the endocardium in ICM and on the epicardium in PMC. Endo-/epicardial facing LAVA were frequently found within SWT areas (91% in <2 mm, 9% in 2-5 mm, and 0% in >5 mm, P < .001). In SWT areas, the presence of endocardial LAVA in ICM and epicardial LAVA in PMC predicted opposite facing LAVA with sensitivity and specificity of 78% and 48% and 79% and 98%, respectively. SWT predicted epicardial LAVA in ICM and endocardial LAVA in PMC with sensitivity and specificity of 89% and 100%, and 100% and 100%, respectively., Conclusion: SWT is frequently found in ICM and PMC but is not common in DCM. SWT predicts LAVA on the opposite side of the wall (epicardial in ICM and endocardial in PMC), indicating transmural VT substrate. MDCT is useful for identifying VT substrate and helpful for understanding the mechanisms of the location of VT substrate domain., (Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Aims: Left ventricular (LV) lead implantation through the coronary sinus (CS) can be limited and sometimes not possible-alternative approaches are needed. Minimally invasive, robotically guided LV lead implantation has major advantages, but there are little published data about the short- and long-term follow-ups, in terms of feasibility, safety, electrical performance, and impact on clinical outcome., Methods and Results: A total of 21 heart failure patients underwent robotically guided LV lead implantation using the Da Vinci Robotic System. Indications were failed implant with conventional approach through the CS (n = 16) and non-response to conventional cardiac resynchronization therapy (n = 5). During the procedure, the entire LV free wall was exposed through 3 transthoracic ports (10 mm diameter each) allowing ample choice of stimulation site and the ability to implant 2 LV leads via a Y connector. Patients were prospectively followed up for 1 year. The two LV leads were successfully implanted in all patients. No peri-procedural complications were observed. After a mean stay in the intensive care unit of 1.2 ± 4 days, the 21 patients were hospitalized in the EP department for 6.7 ± 2.9 days. Acute LV thresholds were excellent (1.0 V ± 0.6/0.4 ms) and stayed stable at 1-year follow-up (1.5 V ± 0.6/0.4 ms, P = 0.21). Four patients demonstrated an increased threshold (>2 V/0.4 ms). There was no phrenic nerve stimulation. After 12 months, in the failed implant group, 69% of the patients were echocardiographic and clinical responders., Conclusion: The robotic approach was feasible, safe, and minimally invasive. Accordingly, robotically guided LV lead implantation seems to offer a new alternative when conventional approaches are not suitable., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.)

Background: 18-Fluorodeoxyglucose positron emission tomography/computerized tomography (FDG PET/CT) scanning has recently been proposed as a diagnostic tool for lead endocarditis (LE)., Objective: FDG PET/CT might be also useful to localize associated septic emboli in patients with LE., Case Presentation: We report an interesting case of a LE patient with a prosthetic aortic valve in whom a trans-esophageal echocardiogram did not show associated aortic endocarditis. FDG PET/CT revealed prosthetic aortic valve infection. A second TEE performed 2 weeks after identified aortic vegetation. A longer duration of antimicrobial therapy with serial follow-up echocardiography was initiated. There was also increased uptake in the sigmoid colon, corresponding to focal polyps resected during a colonoscopy., Conclusion: FDG PET/CT scanning seems to be highly sensitive for prosthetic aortic valve endocarditis diagnosis. This promising diagnostic tool may be beneficial in LE patients, by identifying septic emboli and potential sites of pathogen entry.

Currently, no non-invasive cardiac pacing device acceptable for prolonged use in conscious patients exists. High Intensity Focused Ultrasound (HIFU) can be used to perform remote pacing using reversibility of electromechanical coupling of cardiomyocytes. Here we described an extracorporeal cardiac stimulation device and study its efficacy and safety. We conducted experiments ex vivo and in vivo in a large animal model (pig) to evaluate clinical potential of such a technique. The stimulation threshold was determined in 10 different ex vivo hearts and different clinically relevant electrical effects such as consecutive stimulations of different heart chambers with a single ultrasonic probe, continuous pacing or the inducibility of ventricular tachycardia were shown. Using ultrasonic contrast agent, consistent cardiac stimulation was achievable in vivo for up to 1 hour sessions in 4 different animals. No damage was observed in inversion-recovery MR sequences performed in vivo in the 4 animals. Histological analysis revealed no differences between stimulated and control regions, for all ex vivo and in vivo cases.

Background : Rates of pacemaker implantation are steadily increasing and as patients are living longer, endovenous leads remain implanted for an extended period of time thereby increasing the risk of cardiac implantable electronic device (CIED) infection. Investigating fever of unknown origin in patients with implanted pacemakers can be challenging. Recently, 18 F-fluorodeoxyglucose positron emission tomography/computerised tomography ( 18 F-FDG-PET/CT) scanning has been used as a diagnostic tool for lead endocarditis in small studies. Objectives : ENDOTEP is a prospective and multicentre study designed to evaluate the accuracy of 18 F-FDG-PET/CT scanning in the diagnosis of lead endocarditis. Methods : A total of 250 patients referred for pacemaker extraction due to suspicion of an infected device will be prospectively enrolled in six French regional centres for investigation and treatment of CIED infection. 18 F-FDG-PET/CT scanning (index test) will be performed in each patient in the 48 hours preceding lead extraction. Bacteriological cultures (reference standard) will assess the presence of lead endocarditis, blind to 18 F-FDG-PET/CT results. Enrolment started in June 2015 and is expected to end by June 2017. The primary objective will be to establish the sensitivity of the 18 F-FDG-PET/CT scan for lead endocarditis. Secondary objectives will include other accuracy parameters, inter-observer agreement in the interpretation of 18 F-FDG-PET/CT scanning, the influence of previous antibiotic therapy on 18 F-FDG-PET/CT diagnostic accuracy and assessment of septic emboli associated to lead endocarditis. Conclusion : The ENDOTEP study will examine the ability of 18 F-FDG-PET/CT scanning to avoid possible false-positive results, as is common using the current usual diagnostic strategy and may lead to unnecessary extraction of implants in patients with suspected lead infection., Competing Interests: Disclosure: This research was conducted with the financing of Bordeaux University Hospital (source of grants: PHRC Hospital Program of Clinical Research).

Background: Complex fractionated atrial electrograms (CFAEs) have long been associated with proarrhythmic alterations in atrial structure or electrophysiology. Structural alterations disrupt and slow smoothly propagating wavefronts, leading to wavebreaks and electrogram (EGM) fractionation, but the exact nature and characteristics for arrhythmia remain unknown. Clinically, in atrial fibrillation (AF) patients, increases in frequency, whether by pacing or fibrillation, increase EGM fractionation and duration, and reentry can occur in relation with the conduction disturbance. Recently, percolation has been proposed as an arrhythmogenic mechanism, but its role in AF has not been investigated., Objective: We sought to determine if percolation can explain reentry formation and EGM behavior observed in AF patients., Methods: Computer models of fibrotic tissue with different densities were generated based on late gadolinium-enhanced magnetic resonance images, using pixel intensity as a fibrosis probability to avoid an arbitrary binary threshold. Clinical pacing protocols were followed to induce AF, and EGMs were computed., Results: Reentry could be elicited, with a biphasic behavior dependent on fibrotic density. CFAEs were recorded above fibrotic regions, and consistent with clinical data, EGM duration and fractionation increased with more rapid pacing., Conclusion: These findings confirm percolation as a potential mechanism to explain AF in humans and give new insights into dynamics underlying conduction distortions and fractionated signals in excitable media, which correlate well with the experimental findings in fibrotic regions. The greater understanding of the different patterns of conduction changes and related EGMs could lead to more individualized and effective approaches to AF ablation therapy., (Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Background: During the past years, many innovations have been introduced to facilitate catheter ablation of post-myocardial infarction ventricular tachycardia. However, the predictors of outcome after ablation were not thoroughly studied., Methods and Results: From 2009 to 2013, consecutive patients referred for post-myocardial infarction ventricular tachycardia ablation were included. The end point of the procedure was complete elimination of local abnormal ventricular activities (LAVA) and ventricular tachycardia (VT) noninducibility. The predictors of outcome with primary end point of VT recurrence were assessed. A total of 125 patients were included (age: 64±11 years; 7 women) for 142 procedures. The left ventricle was accessed via transseptal, retrograde aortic, and epicardial approaches in 87%, 33%, and 37% of patients, respectively. Three-dimensional electroanatomical mapping system was used in 70%, multipolar catheter in 51%, and real-time image integration in 38% (from magnetic resonance imaging in 39% and multidetector computed tomography in 93%) of patients. Before ablation, VT was inducible in 75%, and endocardial/epicardial LAVA were present in 88%/75%. After ablation, complete LAVA elimination was achieved in 60%, and VT noninducibility in 83%. During a median follow-up of 850 days (interquartile range, 439-1707), VT recurrence was observed in 36%. Multivariable analysis identified 3 independent outcome predictors: the ability to achieve complete LAVA elimination (R(2)=0.29; P<0.0001; risk ratio=0.52 [0.38-0.70]), the use of real-time image integration (R(2)=0.21; P=0.0006; risk ratio=0.49 [0.33-0.74]), and the use of multipolar catheters (R(2)=0.08; P=0.05; risk ratio=0.75 [0.56-1.00])., Conclusions: Achievement of complete LAVA elimination and use of scar integration from imaging and multipolar catheters to focus high-density mapping are independent predictors of VT-free survival after catheter ablation for post-myocardial infarction ventricular tachycardia., (© 2016 American Heart Association, Inc.)

Background: Although multi-detector computed tomography (MDCT) and cardiac magnetic resonance (CMR) can assess the structural substrate of ventricular tachycardia (VT) in ischemic cardiomyopathy (ICM), non-ICM (NICM), and arrhythmogenic right ventricular cardiomyopathy (ARVC), the usefulness of systematic image integration during VT ablation remains undetermined., Methods and Results: A total of 116 consecutive patients (67 ICM; 30 NICM; 19 ARVC) underwent VT ablation with image integration (MDCT 91%; CMR 30%; both 22%). Substrate was defined as wall thinning on MDCT and late gadolinium-enhancement on CMR in ICM/NICM, and as myocardial hypo-attenuation on MDCT in ARVC. This substrate was compared to mapping and ablation results with the endpoint of complete elimination of local abnormal ventricular activity (LAVA), and the impact of image integration on procedural management was analyzed. Imaging-derived substrate identified 89% of critical VT isthmuses and 85% of LAVA, and was more efficient in identifying LAVA in ICM and ARVC than in NICM (90% and 90% vs. 72%, P < 0.0001), and when defined from CMR than MDCT (ICM: 92% vs. 88%, P = 0.026, NICM: 88% vs. 72%, P < 0.001). Image integration motivated additional mapping and epicardial access in 57% and 33% of patients. Coronary and phrenic nerve integration modified epicardial ablation strategy in 43% of patients. The impact of image integration on procedural management was higher in ARVC/NICM than in ICM (P < 0.01), and higher in case of epicardial approach (P < 0.0001)., Conclusions: Image integration is feasible in large series of patients, provides information on VT substrate, and impacts procedural management, particularly in ARVC/NICM, and in case of epicardial approach., (© 2016 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals, Inc.)