Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 604
Filtrar
2.
EuroIntervention ; 20(14): e887-e897, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39007829

RESUMEN

BACKGROUND: Transcatheter mitral valve replacement (TMVR) is a therapeutic option for patients with severe mitral regurgitation (MR) who are ineligible for conventional surgery. There are limited data on the outcomes of large patient cohorts treated with TMVR. AIMS: This study aimed to investigate the outcomes and predictors of mortality for patients treated with transapical TMVR. METHODS: This analysis represents the clinical experience of all patients enrolled in the Tendyne Expanded Clinical Study. Patients with symptomatic MR underwent transapical TMVR with the Tendyne system between November 2014 and June 2020. Outcomes and adverse events up to 2 years, as well as predictors of short-term mortality, were assessed. RESULTS: A total of 191 patients were treated (74.1±8.0 years, 62.8% male, Society of Thoracic Surgeons Predicted Risk of Mortality 7.7±6.6%). Technical success was achieved in 96.9% (185/191), and there were no intraprocedural deaths. At 30-day, 1- and 2-year follow-up, the rates of all-cause mortality were 7.9%, 30.8% and 40.5%, respectively. Complete MR elimination (MR <1+) was observed in 99.3%, 99.1% and 96.3% of patients, respectively. TMVR treatment resulted in consistent improvement of New York Heart Association Functional Class and quality of life up to 2 years (both p<0.001). Independent predictors of early mortality were age (odds ratio [OR] 1.11; p=0.003), pulmonary hypertension (OR 3.83; p=0.007), and institutional experience (OR 0.40; p=0.047). CONCLUSIONS: This study investigated clinical outcomes in the full cohort of patients included in the Tendyne Expanded Clinical Study. The Tendyne TMVR system successfully eliminated MR with no intraprocedural deaths, resulting in an improvement in symptoms and quality of life. Continued refinement of clinical and echocardiographic risks will be important to optimise longitudinal outcomes.


Asunto(s)
Cateterismo Cardíaco , Implantación de Prótesis de Válvulas Cardíacas , Insuficiencia de la Válvula Mitral , Válvula Mitral , Humanos , Insuficiencia de la Válvula Mitral/cirugía , Insuficiencia de la Válvula Mitral/diagnóstico por imagen , Insuficiencia de la Válvula Mitral/fisiopatología , Insuficiencia de la Válvula Mitral/mortalidad , Masculino , Femenino , Implantación de Prótesis de Válvulas Cardíacas/métodos , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Anciano , Válvula Mitral/cirugía , Válvula Mitral/diagnóstico por imagen , Válvula Mitral/fisiopatología , Resultado del Tratamiento , Anciano de 80 o más Años , Cateterismo Cardíaco/métodos , Cateterismo Cardíaco/efectos adversos , Cateterismo Cardíaco/instrumentación , Prótesis Valvulares Cardíacas , Factores de Riesgo , Persona de Mediana Edad
3.
Heart Rhythm ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38971416

RESUMEN

BACKGROUND: Cardiac resynchronization therapy (CRT) is associated with challenges such as elevated capture thresholds, diaphragmatic stimulation, and lead instability. OBJECTIVE: Assess the chronic safety and efficacy of the quadripolar CRT-D device system with the Quartet 1458Q Left Ventricular (LV) lead in a CRT-indicated population followed for 5 years and evaluate all-cause mortality and impact of baseline characteristics on survival through 5 years. METHODS: Patients indicated for a CRT-D system were followed every 6 months post-implant for 5 years and assessed device performance and adverse events at each visit. The three primary endpoints were freedom from quadripolar CRT-D system-related complications through 5 years, freedom from Quartet 1458Q LV lead-related complications through 5 years, and the mean programmed pacing capture threshold at 5 years. RESULTS: The study enrolled 1,970 subjects at 71 sites. The quadripolar CRT-D system was successfully implanted in 97.2% of subjects. Freedom from quadripolar CRT-D device system-related complications through 5 years was 89.7% and freedom from Quartet 1458Q LV lead-related complications through 5 years was 95.7%. 3.49 % of subjects had LV lead-related complications and an overall LV lead complication rate was 0.0122 events per subject-year. A mean LV pacing capture threshold was 1.52 ± 1.01 V at 5 years. The 5-year survival rate was 67.4%. CONCLUSION: The quadripolar CRT-D system with the Quartet 1458Q LV lead exhibited low rates of complications and stable electrical performance through 5 years of follow-up and suggested a higher 5-year survival rate compared to traditional CRT systems.

4.
Eur Heart J Imaging Methods Pract ; 2(2): qyae026, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-39045464

RESUMEN

Aims: The morphology and function of the left atrium (LA) are intimately tied to left ventricular loading conditions. Data pertaining to the effect of transcatheter aortic valve replacement (TAVR) on LA function and geometry are scarce. The aim of the study was to quantify associations between TAVR and LA remodelling by pooling available data from published observational studies. Methods and results: A systematic review and meta-analysis were performed. Studies reporting serial LA speckle-tracking echocardiographic (STE) data, before and after TAVR, were included. Other outcome data included LA area and indexed volume (LAVi) and standard chamber measurements. Outcomes were stratified by timing of follow-up echocardiography: early (<6 months) or late (≥6 months). Twelve studies were included, comprising 1066 patients. The mean reduction in LAVi was 2.72 mL/m2 [95% confidence interval (CI) 1.37-4.06, P < 0.01]. LA reservoir function improved overall by a mean difference (MD) of 3.71% (95% CI 1.82-5.6, P < 0.01), although there was significant heterogeneity within the pooled studies (I 2 = 87.3%). Significant improvement in reservoir strain was seen in both early follow-up (MD 3.1%, P < 0.01) and late follow-up studies (MD 4.48%, P = 0.03), but heterogeneity remained high (I 2 = 65.23 and 94.4%, respectively). Six studies reported a change in LA contractile function, which recovered in the early follow-up studies (MD 2.26, P < 0.01), but not in the late group (MD 1.41, P = 0.05). Pooled improvement in LA booster function was 1.96% (95% CI 1.11-2.8, P < 0.01). Conclusion: TAVR is associated with significant negative LA remodelling, and an improvement in LA mechanics, quantified by STE. The prognostic implications of these findings require further study.

6.
J Cardiovasc Dev Dis ; 11(6)2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38921682

RESUMEN

AIM: To assess the acute effect of empagliflozin versus dapagliflozin administration on flow-mediated vasodilation in patients with type 2 diabetes mellitus. DESIGN: A double-blind clinical trial, at the Experimental and Clinical Therapeutics Institute, University Health Sciences Center, at the Universidad de Guadalajara, in inpatients with T2D according to the 2023 ADA criteria. METHODS: Thirty patients (15 males and 15 females), aged between 35 and 65 years, were included in this study, according to the 2023 ADA criteria. The eligible patients were randomly assigned to three groups: empagliflozin 25 mg once daily, dapagliflozin 10 mg once daily, or placebo once daily. Anthropometric parameters were taken using validated techniques. FMD was measured using a high-resolution semiautomatic ultrasound UNEX-EF 38G (UNEX Co., Ltd., Nagoya, Japan). Arterial tension was determined with the OMRON electronic digital sphygmomanometer (HEM 907 XL, Kyoto, Japan). RESULTS: The group of patients who received empagliflozin had a significantly lower baseline flow-mediated dilation (FMD) compared to the group receiving dapagliflozin (p = 0.017); at the end of this study, the empagliflozin group achieved a comparable FMD to the dapagliflozin group (p = 0.88). CONCLUSION: After the treatment period, the empagliflozin and dapagliflozin groups achieved similar FMD, suggesting a class effect.

7.
Nat Commun ; 15(1): 5400, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38926403

RESUMEN

Oxide heterostructures exhibit a vast variety of unique physical properties. Examples are unconventional superconductivity in layered nickelates and topological polar order in (PbTiO3)n/(SrTiO3)n superlattices. Although it is clear that variations in oxygen content are crucial for the electronic correlation phenomena in oxides, it remains a major challenge to quantify their impact. Here, we measure the chemical composition in multiferroic (LuFeO3)9/(LuFe2O4)1 superlattices, mapping correlations between the distribution of oxygen vacancies and the electric and magnetic properties. Using atom probe tomography, we observe oxygen vacancies arranging in a layered three-dimensional structure with a local density on the order of 1014 cm-2, congruent with the formula-unit-thick ferrimagnetic LuFe2O4 layers. The vacancy order is promoted by the locally reduced formation energy and plays a key role in stabilizing the ferroelectric domains and ferrimagnetism in the LuFeO3 and LuFe2O4 layers, respectively. The results demonstrate pronounced interactions between oxygen vacancies and the multiferroic order in this system and establish an approach for quantifying the oxygen defects with atomic-scale precision in 3D, giving new opportunities for deterministic defect-enabled property control in oxide heterostructures.

8.
J Am Chem Soc ; 146(26): 17613-17617, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38885442

RESUMEN

Synthesis of high-entropy oxide (HEO) nanocrystals has focused on increasing the temperature in the entropy term (T(ΔS)) to overcome the enthalpy term. However, these high temperatures lead to large, polydisperse nanocrystals. In this work, we leverage the low solubility product (Ksp) of metal oxides and optimize the Lewis-acid-catalyzed esterification reaction for equal rate production of the cation monomers to synthesize HEO nanocrystals at low temperatures, producing the smallest (<4 nm) and most monodisperse (<15% size dispersity) HEOs to date. We apply these HEO nanocrystals as electrocatalysts, exhibiting promising activity toward the oxygen evolution reaction in alkaline media, with an overpotential of 345 mV at 10 mA/cm2.

9.
Catheter Cardiovasc Interv ; 104(1): 155-166, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38819861

RESUMEN

Frailty is a common clinical syndrome that portends poor peri-procedural outcomes and increased mortality following transcatheter valve interventions. We reviewed frailty assessment tools in transcatheter intervention cohorts to recommend a pathway for preprocedural frailty assessment in patients referred for transcatheter valve procedures, and evaluated current evidence for frailty interventions and their efficacy in transcatheter intervention. We recommend the use of a frailty screening instrument to identify patients as frail, with subsequent referral for comprehensive geriatric assessment in these patients, to assist in selecting appropriate patients and then optimizing them for transcatheter valve interventions. Interventions to reduce preprocedural frailty are not well defined, however, data from limited cohort studies support exercise-based interventions to increase functional capacity and reduce frailty in parallel with preprocedural medical optimization.


Asunto(s)
Anciano Frágil , Fragilidad , Evaluación Geriátrica , Humanos , Fragilidad/diagnóstico , Fragilidad/fisiopatología , Resultado del Tratamiento , Factores de Riesgo , Anciano , Medición de Riesgo , Anciano de 80 o más Años , Factores de Edad , Cateterismo Cardíaco/efectos adversos , Estado Funcional , Femenino , Masculino , Selección de Paciente , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Valor Predictivo de las Pruebas , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/mortalidad , Toma de Decisiones Clínicas , Enfermedades de las Válvulas Cardíacas/fisiopatología , Enfermedades de las Válvulas Cardíacas/cirugía , Enfermedades de las Válvulas Cardíacas/mortalidad , Enfermedades de las Válvulas Cardíacas/diagnóstico por imagen , Enfermedades de las Válvulas Cardíacas/terapia , Estado de Salud
10.
Metab Eng ; 85: 26-34, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38802041

RESUMEN

Integration of novel compounds into biological processes holds significant potential for modifying or expanding existing cellular functions. However, the cellular uptake of these compounds is often hindered by selectively permeable membranes. We present a novel bacterial transport system that has been rationally designed to address this challenge. Our approach utilizes a highly promiscuous sulfonate membrane transporter, which allows the passage of cargo molecules attached as amides to a sulfobutanoate transport vector molecule into the cytoplasm of the cell. These cargoes can then be unloaded from the sulfobutanoyl amides using an engineered variant of the enzyme γ-glutamyl transferase, which hydrolyzes the amide bond and releases the cargo molecule within the cell. Here, we provide evidence for the broad substrate specificity of both components of the system by evaluating a panel of structurally diverse sulfobutanoyl amides. Furthermore, we successfully implement the synthetic uptake system in vivo and showcase its functionality by importing an impermeant non-canonical amino acid.

11.
Nat Commun ; 15(1): 3828, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714653

RESUMEN

Stabilization of topological spin textures in layered magnets has the potential to drive the development of advanced low-dimensional spintronics devices. However, achieving reliable and flexible manipulation of the topological spin textures beyond skyrmion in a two-dimensional magnet system remains challenging. Here, we demonstrate the introduction of magnetic iron atoms between the van der Waals gap of a layered magnet, Fe3GaTe2, to modify local anisotropic magnetic interactions. Consequently, we present direct observations of the order-disorder skyrmion lattices transition. In addition, non-trivial topological solitons, such as skyrmioniums and skyrmion bags, are realized at room temperature. Our work highlights the influence of random spin control of non-trivial topological spin textures.

12.
Biotechnol Bioeng ; 121(7): 2225-2233, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38678541

RESUMEN

Process in-line monitoring and control are crucial to optimize the productivity of bioprocesses. A frequently applied Process Analytical Technology (PAT) tool for bioprocess in-line monitoring is Raman spectroscopy. However, evaluating bioprocess Raman spectra is complex and calibrating state-of-the-art statistical evaluation models is effortful. To overcome this challenge, we developed an Indirect Hard Modeling (IHM) prediction model in a previous study. The combination of Raman spectroscopy and the IHM prediction model enables non-invasive in-line monitoring of glucose and ethanol mass fractions during yeast fermentations with significantly less calibration effort than comparable approaches based on statistical models. In this study, we advance this IHM-based approach and successfully demonstrate that the combination of Raman spectroscopy and IHM is capable of not only bioprocess monitoring but also bioprocess control. For this purpose, we used this combination's in-line information as input of a simple on-off glucose controller to control the glucose mass fraction in Saccharomyces cerevisiae fermentations. When we performed two of these fermentations with different predefined glucose set points, we achieved similar process control quality as approaches using statistical models, despite considerably smaller calibration effort. Therefore, this study reaffirms that the combination of Raman spectroscopy and IHM is a powerful PAT tool for bioprocesses.


Asunto(s)
Etanol , Glucosa , Saccharomyces cerevisiae , Espectrometría Raman , Espectrometría Raman/métodos , Saccharomyces cerevisiae/metabolismo , Glucosa/metabolismo , Glucosa/análisis , Etanol/metabolismo , Etanol/análisis , Fermentación , Modelos Biológicos , Reactores Biológicos
13.
ACS Appl Mater Interfaces ; 16(19): 25432-25444, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38688003

RESUMEN

Encapsulating an electrocatalytic material with a semipermeable, nanoscopic oxide overlayer offers a promising approach to enhancing its stability, activity, and/or selectivity compared to an unencapsulated electrocatalyst. However, applying nanoscopic oxide encapsulation layers to high-surface-area electrodes such as nanoparticle-supported porous electrodes is a challenging task. This study demonstrates that the recently developed condensed layer deposition (CLD) method can be used for depositing nanoscopic (sub-10 nm thick) titanium dioxide (TiO2) overlayers onto high-surface-area platinized carbon foam electrodes. Characterization of the overlayers by transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS) showed that the films are amorphous, while X-ray photoelectron spectroscopy confirmed that they exhibit TiO2 stoichiometry. Electrodes were also characterized by hydrogen underpotential deposition (Hupd) and carbon monoxide (CO) stripping, demonstrating that the Pt electrocatalysts remain electrochemically active after encapsulation. Additionally, copper underpotential deposition (Cuupd) measurements revealed that TiO2 overlayers are effective at blocking Cu2+ from reaching the TiO2/Pt buried interface and were used to estimate that between 43 and 98% of Pt surface sites were encapsulated. Overall, this study shows that CLD is a promising approach for depositing nanoscopic protective overlayers on high-surface-area electrodes.

14.
J Gen Virol ; 105(1)2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38271027

RESUMEN

The COVID-19 pandemic has highlighted the need for vaccines capable of providing rapid and robust protection. One way to improve vaccine efficacy is delivery via microarray patches, such as the Vaxxas high-density microarray patch (HD-MAP). We have previously demonstrated that delivery of a SARS-CoV-2 protein vaccine candidate, HexaPro, via the HD-MAP induces potent humoral immune responses. Here, we investigate the cellular responses induced by HexaPro HD-MAP vaccination. We found that delivery via the HD-MAP induces a type one biassed cellular response of much greater magnitude as compared to standard intramuscular immunization.


Asunto(s)
COVID-19 , Glicoproteína de la Espiga del Coronavirus , Animales , Ratones , Humanos , Glicoproteína de la Espiga del Coronavirus/genética , Pandemias , COVID-19/prevención & control , SARS-CoV-2 , Vacunación , Inmunidad Celular , Vacunas contra la COVID-19 , Anticuerpos Antivirales , Inmunidad Humoral , Anticuerpos Neutralizantes
15.
JAMA Cardiol ; 9(3): 254-261, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38265806

RESUMEN

Importance: Spontaneous coronary artery dissection (SCAD) is a poorly understood cause of acute coronary syndrome that predominantly affects women. Evidence to date suggests a complex genetic architecture, while a family history is reported for a minority of cases. Objective: To determine the contribution of rare and common genetic variants to SCAD risk in familial cases, the latter via the comparison of a polygenic risk score (PRS) with those with sporadic SCAD and healthy controls. Design, Setting, and Participants: This genetic association study analyzed families with SCAD, individuals with sporadic SCAD, and healthy controls. Genotyping was undertaken for all participants. Participants were recruited between 2017 and 2021. A PRS for SCAD was calculated for all participants. The presence of rare variants in genes associated with connective tissue disorders (CTD) was also assessed. Individuals with SCAD were recruited via social media or from a single medical center. A previously published control database of older healthy individuals was used. Data were analyzed from January 2022 to October 2023. Exposures: PRS for SCAD comprised of 7 single-nucleotide variants. Main Outcomes and Measures: Disease status (familial SCAD, sporadic SCAD, or healthy control) associated with PRS. Results: A total of 13 families with SCAD (27 affected and 12 unaffected individuals), 173 individuals with sporadic SCAD, and 1127 healthy controls were included. A total of 188 individuals with SCAD (94.0%) were female, including 25 of 27 with familial SCAD and 163 of 173 with sporadic SCAD; of 12 unaffected individuals from families with SCAD, 6 (50%) were female; and of 1127 healthy controls, 672 (59.6%) were female. Compared with healthy controls, the odds of being an affected family member or having sporadic SCAD was significantly associated with a SCAD PRS (where the odds ratio [OR] represents an increase in odds per 1-SD increase in PRS) (affected family member: OR, 2.14; 95% CI, 1.78-2.50; adjusted P = 1.96 × 10-4; sporadic SCAD: OR, 1.63; 95% CI, 1.37-1.89; adjusted P = 5.69 × 10-4). This association was not seen for unaffected family members (OR, 1.03; 95% CI, 0.46-1.61; adjusted P = .91) compared with controls. Further, those with familial SCAD were overrepresented in the top quintile of the control PRS distribution (OR, 3.70; 95% CI, 2.93-4.47; adjusted P = .001); those with sporadic SCAD showed a similar pattern (OR, 2.51; 95% CI, 1.98-3.04; adjusted P = .001). Affected individuals within a family did not share any rare deleterious variants in CTD-associated genes. Conclusions and Relevance: Extreme aggregation of common genetic risk appears to play a significant role in familial clustering of SCAD as well as in sporadic case predisposition, although further study is required.


Asunto(s)
Anomalías de los Vasos Coronarios , Vasos Coronarios , Enfermedades Vasculares , Enfermedades Vasculares/congénito , Humanos , Femenino , Masculino , Enfermedades Vasculares/genética , Factores de Riesgo , Genotipo , Puntuación de Riesgo Genético
16.
Environ Res ; 248: 118290, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38280529

RESUMEN

Headache is a common condition with a substantial burden of disease worldwide. Concerns have been raised over the potential impact of long-term mobile phone use on headache due to radiofrequency electromagnetic fields (RF-EMFs). We explored prospectively the association between mobile phone use at baseline (2009-2012) and headache at follow-up (2015-2018) by analysing pooled data consisting of the Dutch and UK cohorts of the Cohort Study of Mobile Phone Use and Health (COSMOS) (N = 78,437). Frequency of headache, migraine, and information on mobile phone use, including use of hands-free devices and frequency of texting, were self-reported. We collected objective operator data to obtain regression calibrated estimates of voice call duration. In the model mutually adjusted for call-time and text messaging, participants in the high category of call-time showed an adjusted odds ratio (OR) of 1.04 (95 % CI: 0.94-1.15), with no clear trend of reporting headache with increasing call-time. However, we found an increased risk of weekly headache (OR = 1.40, 95 % CI: 1.25-1.56) in the high category of text messaging, with a clear increase in reporting headache with increasing texting. Due to the negligible exposure to RF-EMFs from texting, our results suggest that mechanisms other than RF-EMFs are responsible for the increased risk of headache that we found among mobile phone users.


Asunto(s)
Uso del Teléfono Celular , Teléfono Celular , Humanos , Estudios de Cohortes , Países Bajos , Ondas de Radio , Campos Electromagnéticos , Cefalea , Reino Unido
17.
BMC Nephrol ; 25(1): 24, 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38238661

RESUMEN

This narrative review highlights strategies proposed by the Mexican Group of Experts on Arterial Hypertension endorsed to prevent, diagnose, and treat chronic kidney disease (CKD) related to systemic arterial hypertension (SAH). Given the growing prevalence of CKD in Mexico and Latin America caused by SAH, there is a need for context-specific approaches to address the effects of SAH, given the diverse population and unique challenges faced by the region. This narrative review provides clinical strategies for healthcare providers on preventing, diagnosing, and treating kidney disease related to SAH, focusing on primary prevention, early detection, evidence-based diagnostic approaches, and selecting pharmacological treatments. Key-strategies are focused on six fundamental areas: 1) Strategies to mitigate kidney disease in SAH, 2) early detection of CKD in SAH, 3) diagnosis and monitoring of SAH, 4) blood pressure targets in patients living with CKD, 5) hypertensive treatment in patients with CKD and 6) diuretics and Non-Steroidal Mineralocorticoid Receptor Inhibitors in Patients with CKD. This review aims to provide relevant strategies for the Mexican and Latin American clinical context, highlight the importance of a multidisciplinary approach to managing SAH, and the role of community-based programs in improving the quality of life for affected individuals. This position paper seeks to contribute to reducing the burden of SAH-related CKD and its complications in Mexico and Latin America.


Asunto(s)
Hipertensión , Insuficiencia Renal Crónica , Humanos , México/epidemiología , Calidad de Vida , Hipertensión/diagnóstico , Hipertensión/tratamiento farmacológico , Hipertensión/epidemiología , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/epidemiología , Presión Sanguínea
18.
J Am Soc Echocardiogr ; 37(1): 64-76, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37805144

RESUMEN

Contemporary echocardiographic criteria for grading aortic stenosis severity have remained relatively unchanged, despite significant advances in noninvasive imaging techniques over the last 2 decades. More recently, attention has shifted to the ventricular response to aortic stenosis and how this might be quantified. Global longitudinal strain, semiautomatically calculated from standard two-dimensional echocardiographic images, has been the focus of extensive research. Global longitudinal strain is a sensitive marker of subtle hypertrophy-related impairment in left ventricular function and has shown promise as a relatively robust prognostic marker, both independently and when added to severity classification systems. Herein we review the pathophysiological basis underpinning the potential utility of global longitudinal strain in the assessment of aortic stenosis, as well as its potential role in quantifying myocardial recovery and prognostic discrimination following aortic valve replacement.


Asunto(s)
Estenosis de la Válvula Aórtica , Humanos , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Función Ventricular Izquierda/fisiología , Ecocardiografía/métodos , Válvula Aórtica/diagnóstico por imagen , Pronóstico , Índice de Severidad de la Enfermedad
19.
Small ; 20(9): e2305437, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37863807

RESUMEN

Organic Photovoltaics (OPV) is a very promising technology to harvest artificial illumination and power smart devices of the Internet of Things (IoT). Efficiencies as high as 30.2% have been reported for OPVs under warm white light-emitting diode (LED) light. This is due to the narrow spectrum of indoor light, which leads to an optimal bandgap of ≈1.9 eV. Under full sunlight, OPV devices often suffer from poor stability compared to the established inorganic PV technologies such as crystalline silicon. This study focuses on a potentially very cost-effective Indium Tin Oxide (ITO) free cell stack with absorber materials processed from non-halogenated solvents. These organic solar cells and modules with efficiencies up to 21% can already achieve remarkable stabilities under typical indoor illumination. Aging under 50,000 lux LED lighting leads to very little degradation after more than 11 000 h. This light dose corresponds to more than 110 years under 500 lux. For modules encapsulated with a flexible barrier, extrapolated lifetimes of more than 41 years are achieved. This shows that OPV is mature for the specific application under indoor illumination. Due to the large number of potential organic semiconducting materials, further efficiency increase can be expected.

20.
Adv Mater ; 36(13): e2305739, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37800466

RESUMEN

Magnetic van der Waals heterostructures provide a unique platform to study magnetism and spintronics device concepts in the 2D limit. Here, studies of exchange bias from the van der Waals antiferromagnet CrSBr acting on the van der Waals ferromagnet Fe3GeTe2 (FGT) are reported. The orientation of the exchange bias is along the in-plane easy axis of CrSBr, perpendicular to the out-of-plane anisotropy of the FGT, inducing a strongly tilted magnetic configuration in the FGT. Furthermore, the in-plane exchange bias provides sufficient symmetry breaking to allow deterministic spin-orbit torque switching of the FGT in CrSBr/FGT/Pt samples at zero applied magnetic field. A minimum thickness of the CrSBr of >10 nm is needed to provide a non-zero exchange bias at 30 K.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...