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1.
JACC Cardiovasc Imaging ; 17(3): 269-280, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37480907

RESUMEN

BACKGROUND: The recent development of artificial intelligence-guided quantitative coronary computed tomography angiography analysis (AI-QCT) has enabled rapid analysis of atherosclerotic plaque burden and characteristics. OBJECTIVES: This study set out to investigate the 10-year prognostic value of atherosclerotic burden derived from AI-QCT and to compare the spectrum of plaque to manually assessed coronary computed tomography angiography (CCTA), coronary artery calcium scoring (CACS), and clinical risk characteristics. METHODS: This was a long-term follow-up study of 536 patients referred for suspected coronary artery disease. CCTA scans were analyzed with AI-QCT and plaque burden was classified with a plaque staging system (stage 0: 0% percentage atheroma volume [PAV]; stage 1: >0%-5% PAV; stage 2: >5%-15% PAV; stage 3: >15% PAV). The primary major adverse cardiac event (MACE) outcome was a composite of nonfatal myocardial infarction, nonfatal stroke, coronary revascularization, and all-cause mortality. RESULTS: The mean age at baseline was 58.6 years and 297 patients (55%) were male. During a median follow-up of 10.3 years (IQR: 8.6-11.5 years), 114 patients (21%) experienced the primary outcome. Compared to stages 0 and 1, patients with stage 3 PAV and percentage of noncalcified plaque volume of >7.5% had a more than 3-fold (adjusted HR: 3.57; 95% CI 2.12-6.00; P < 0.001) and 4-fold (adjusted HR: 4.37; 95% CI: 2.51-7.62; P < 0.001) increased risk of MACE, respectively. Addition of AI-QCT improved a model with clinical risk factors and CACS at different time points during follow-up (10-year AUC: 0.82 [95% CI: 0.78-0.87] vs 0.73 [95% CI: 0.68-0.79]; P < 0.001; net reclassification improvement: 0.21 [95% CI: 0.09-0.38]). Furthermore, AI-QCT achieved an improved area under the curve compared to Coronary Artery Disease Reporting and Data System 2.0 (10-year AUC: 0.78; 95% CI: 0.73-0.83; P = 0.023) and manual QCT (10-year AUC: 0.78; 95% CI: 0.73-0.83; P = 0.040), although net reclassification improvement was modest (0.09 [95% CI: -0.02 to 0.29] and 0.04 [95% CI: -0.05 to 0.27], respectively). CONCLUSIONS: Through 10-year follow-up, AI-QCT plaque staging showed important prognostic value for MACE and showed additional discriminatory value over clinical risk factors, CACS, and manual guideline-recommended CCTA assessment.


Asunto(s)
Enfermedad de la Arteria Coronaria , Placa Aterosclerótica , Humanos , Masculino , Femenino , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/terapia , Inteligencia Artificial , Estudios de Seguimiento , Valor Predictivo de las Pruebas , Arterias , Angiografía Coronaria
2.
Eur Heart J Open ; 3(2): oead032, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37077580

RESUMEN

Aims: Elevated lipoprotein(a) [Lp(a)] levels are associated with the risk of coronary artery disease (CAD) and calcific aortic valve stenosis (CAVS). Observational studies revealed that Lp(a) and C-reactive protein (CRP) levels, a biomarker of systemic inflammation, may jointly predict CAD risk. Whether Lp(a) and CRP levels also jointly predict CAVS incidence and progression is unknown. Methods and results: We investigated the association of Lp(a) with CAVS according to CRP levels in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk study (n = 18 226, 406 incident cases) and the UK Biobank (n = 438 260, 4582 incident cases), as well as in the ASTRONOMER study (n = 220), which assessed the haemodynamic progression rate of pre-existing mild-to-moderate aortic stenosis. In EPIC-Norfolk, in comparison to individuals with low Lp(a) levels (<50 mg/dL) and low CRP levels (<2.0 mg/L), those with elevated Lp(a) (>50 mg/dL) and low CRP levels (<2.0 mg/L) and those with elevated Lp(a) (>50 mg/dL) and elevated CRP levels (>2.0 mg/L) had a higher CAVS risk [hazard ratio (HR) = 1.86 (95% confidence intervals, 1.30-2.67) and 2.08 (1.44-2.99), respectively]. A comparable predictive value of Lp(a) in patients with vs. without elevated CRP levels was also noted in the UK Biobank. In ASTRONOMER, CAVS progression was comparable in patients with elevated Lp(a) levels with or without elevated CRP levels. Conclusion: Lp(a) predicts the incidence and possibly progression of CAVS regardless of plasma CRP levels. Lowering Lp(a) levels may warrant further investigation in the prevention and treatment of CAVS, regardless of systemic inflammation.

3.
J Int Bioethique Ethique Sci ; 33(2): 11-12, 2023.
Artículo en Francés | MEDLINE | ID: mdl-36894335

RESUMEN

The disappearance of bodies in today’s society is redistributing the cards of living together. If social distancing allows a certain rationalisation of human activities (work, care), does it not paradoxically lead to physical and psychological isolation? Moreover, does the dissociation it leads to between the subject and the “e-mage” given of him or her not tend to transform social relations into an infinite game where half-truths, lies and illusions produce new rituals and artifices depending mainly on technology.


Asunto(s)
Humanos , Masculino , Femenino
4.
Toxicol Res ; 37(4): 405-419, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34631497

RESUMEN

Repeated health and environmental scandals, the loss of biodiversity and the recent burst of chronic diseases constantly remind us the inability of public authorities and risk assessment agencies to protect health and the environment. After reviewing the main shortcomings of our evaluation system of chemicals and new technologies, supported by some concrete examples, we develop a number of proposals to reform both the risk assessment agencies and the evaluation processes. We especially propose the establishment of an independent structure, a High Authority of Expertise, supervising, either at European level or at national level, all the evaluation agencies, and ensuring the transparency, the methodology and the deontology of the expertise. In addition to modifying the evaluation protocols, both in their nature and in their content, especially in order to adapt them to current pollutants such as endocrine disruptors, we propose a reform of the expertise processes based on transparency, contradiction, and greater democracy, including close collaboration between the institutional and scientific parties on the one hand and the whole civil society on the other. All the proposals we make are inspired by the desire to prevent, through appropriate mechanisms, the human, health, ecological, but also economic consequences of contemporary technological choices.

5.
Proc Natl Acad Sci U S A ; 103(25): 9548-53, 2006 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-16769902

RESUMEN

Nuclear retinoic acid receptors (RARs) work as ligand-dependent heterodimeric RAR/retinoid X receptor transcription activators, which are targets for phosphorylations. The N-terminal activation function (AF)-1 domain of RARalpha is phosphorylated by the cyclin-dependent kinase (cdk) 7/cyclin H complex of the general transcription factor TFIIH and the C-terminal AF-2 domain by the cAMP-dependent protein kinase A (PKA). Here, we report the identification of a molecular pathway by which phosphorylation by PKA propagates cAMP signaling from the AF-2 domain to the AF-1 domain. The first step is the phosphorylation of S369, located in loop 9-10 of the AF-2 domain. This signal is transferred to the cyclin H binding domain (at the N terminus of helix 9 and loop 8-9), resulting in enhanced cyclin H interaction and, thereby, greater amounts of RARalpha phosphorylated at S77 located in the AF-1 domain by the cdk7/cyclin H complex. This molecular mechanism relies on the integrity of the ligand-binding domain and the cyclin H binding surface. Finally, it results in higher DNA-binding efficiency, providing an explanation for how cAMP synergizes with retinoic acid for transcription.


Asunto(s)
Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Quinasas Ciclina-Dependientes/metabolismo , Ciclinas/metabolismo , Receptores de Ácido Retinoico/metabolismo , Secuencia de Aminoácidos , Animales , Línea Celular , Chlorocebus aethiops , Ciclina H , ADN/metabolismo , Dimerización , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Fosforilación , Fosfoserina/metabolismo , Unión Proteica , Estructura Cuaternaria de Proteína , Estructura Terciaria de Proteína , Receptores de Ácido Retinoico/química , Receptores de Ácido Retinoico/genética , Receptor alfa de Ácido Retinoico , Transducción de Señal
6.
EMBO J ; 25(4): 739-51, 2006 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-16456540

RESUMEN

Nuclear retinoic acid (RA) receptors (RARs) activate gene expression through dynamic interactions with coregulators in coordination with the ligand and phosphorylation processes. Here we show that during RA-dependent activation of the RARalpha isotype, the p160 coactivator pCIP/ACTR/AIB-1/RAC-3/TRAM-1/SRC-3 is phosphorylated by p38MAPK. SRC-3 phosphorylation has been correlated to an initial facilitation of RARalpha-target genes activation, via the control of the dynamics of the interactions of the coactivator with RARalpha. Then, phosphorylation inhibits transcription via promoting the degradation of SRC-3. In line with this, inhibition of p38MAPK markedly enhances RARalpha-mediated transcription and RA-dependent induction of cell differentiation. SRC-3 phosphorylation and degradation occur only within the context of RARalpha complexes, suggesting that the RAR isotype defines a phosphorylation code through dictating the accessibility of the coactivator to p38MAPK. We propose a model in which RARalpha transcriptional activity is regulated by SRC-3 through coordinated events that are fine-tuned by RA and p38MAPK.


Asunto(s)
Acetiltransferasas/metabolismo , Regulación de la Expresión Génica/fisiología , Proteínas Oncogénicas/metabolismo , Procesamiento Proteico-Postraduccional/fisiología , Receptores de Ácido Retinoico/metabolismo , Transactivadores/metabolismo , Transcripción Genética/fisiología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Células COS , Chlorocebus aethiops , Regulación de la Expresión Génica/efectos de los fármacos , Células HL-60 , Histona Acetiltransferasas , Humanos , Ratones , Complejos Multiproteicos/metabolismo , Coactivador 3 de Receptor Nuclear , Fosforilación/efectos de los fármacos , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Receptor alfa de Ácido Retinoico , Transcripción Genética/efectos de los fármacos , Tretinoina/metabolismo , Tretinoina/farmacología
7.
Proc Natl Acad Sci U S A ; 102(46): 16608-13, 2005 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-16275922

RESUMEN

The transcriptional activity of nuclear retinoic acid receptors (RARs), which act as RAR/retinoid X receptor (RXR) heterodimers, depends on two activation functions, AF-1 and AF-2, which are targets for phosphorylations and synergize for the activation of retinoic acid target genes. The N-terminal AF-1 domain of RARalpha is phosphorylated at S77 by the cyclin-dependent kinase (cdk)-activating kinase (CAK) subcomplex (cdk7/cyclin H/MAT1) of the general transcription factor TFIIH. Here, we show that phosphorylation of S77 governing the transcriptional activity of RARalpha depends on cyclin H binding at a RARalpha region that encompasses loop 8-9 and the N-terminal tip of helix 9 of the AF-2 domain. We propose a model in which the structural constraints of this region control the architecture of the RAR/RXR/TFIIH complex and therefore the efficiency of RARalpha phosphorylation by cdk7. To our knowledge, this study provides the first example of a cooperation between the AF-2 and AF-1 domains of RARs through a kinase complex.


Asunto(s)
Quinasas Ciclina-Dependientes/metabolismo , Ciclinas/metabolismo , Receptores de Ácido Retinoico/metabolismo , Animales , Secuencia de Bases , Línea Celular , Ciclina H , Cartilla de ADN , Modelos Moleculares , Fosforilación , Unión Proteica , ARN Interferente Pequeño , Receptores de Ácido Retinoico/química , Receptores de Ácido Retinoico/fisiología , Receptor alfa de Ácido Retinoico , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Spodoptera , Transcripción Genética/fisiología , Quinasa Activadora de Quinasas Ciclina-Dependientes
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