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1.
Proc Natl Acad Sci U S A ; 121(26): e2316438121, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38900799

RESUMEN

Phase transitions occurring in nonequilibrium conditions can evolve through high-energy intermediate states inaccessible via equilibrium adiabatic conditions. Because of the subtle nature of such hidden phases, their direct observation is extremely challenging and requires simultaneous visualization of matter at subpicoseconds and subpicometer scales. Here, we show that a magnetite crystal in the vicinity of its metal-to-insulator transition evolves through different hidden states when controlled via energy-tuned ultrashort laser pulses. By directly monitoring magnetite's crystal structure with ultrafast electron diffraction, we found that upon near-infrared (800 nm) excitation, the trimeron charge/orbital ordering pattern is destroyed in favor of a phase-separated state made of cubic-metallic and monoclinic-insulating regions. On the contrary, visible light (400 nm) activates a photodoping charge transfer process that further promotes the long-range order of the trimerons by stabilizing the charge density wave fluctuations, leading to the reinforcement of the monoclinic insulating phase. Our results demonstrate that magnetite's structure can evolve through completely different metastable hidden phases that can be reached long after the initial excitation has relaxed, breaking ground for a protocol to control emergent properties of matter.

2.
Neurología (Barc., Ed. impr.) ; 38(6): 419-426, Jul-Ago. 2023. tab
Artículo en Español | IBECS | ID: ibc-222266

RESUMEN

Objetivo: Proporcionar un conjunto de recomendaciones actualizadas y basadas en la evidenciadisponible para el manejo del ictus agudo. Nuestro objetivo es proporcionar una base para eldesarrollo de los protocolos internos de cada centro, sirviendo de referencia para los cuidadosde enfermería. Métodos: Revisión de evidencias disponibles sobre los cuidados del ictus agudo. Se han consultado las guías nacionales e internacionales más recientes. Los niveles de evidencia y grados derecomendación se han basado en la clasificación del Centro de Medicina Basada en la Evidenciade Oxford. Resultados: Se describen la atención y los cuidados del ictus agudo en la fase prehospitalaria,el funcionamiento de código ictus, la atención por el equipo de ictus a la llegada al hospital,los tratamientos de reperfusión y sus limitaciones, el ingreso en la Unidad de Ictus, los cuidadosde enfermería en la Unidad de Ictus y el alta hospitalaria. Conclusiones: Estas pautas proporcionan recomendaciones generales basadas en la evidenciaactualmente disponible para guiar a los profesionales que atienden a pacientes con ictus agudo.En algunos casos, sin embargo, existen datos limitados demostrando la necesidad de continuarinvestigando sobre el manejo del ictus agudo.(AU)


Objective: This study provides a series of updated, evidence-based recommendations for the management of acute stroke. We aim to lay a foundation for the development of individual centres’ internal protocols, serving as a reference for nursing care. Methods: We review the available evidence on acute stroke care. The most recent national and international guidelines were consulted. Levels of evidence and degrees of recommendation are based on the Oxford Centre for Evidence-Based Medicine classification. Results: The study describes prehospital acute stroke care, the operation of the code stroke protocol, care provided by the stroke team upon the patient’s arrival at hospital, reperfusion treatments and their limitations, admission to the stroke unit, nursing care in the stroke unit, and discharge from hospital. Conclusions: These guidelines provide general, evidence-based recommendations to guide professionals who care for patients with acute stroke. However, limited data are available on some aspects, showing the need for continued research on acute stroke management.(AU)


Asunto(s)
Humanos , Enfermería Cardiovascular , Reperfusión , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular/prevención & control , Accidente Cerebrovascular/terapia , Enfermedades del Sistema Nervioso , Protocolos Clínicos , Evaluación en Enfermería
3.
Neurologia (Engl Ed) ; 38(6): 419-426, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37120108

RESUMEN

OBJECTIVE: This study provides a series of updated, evidence-based recommendations for the management of acute stroke. We aim to lay a foundation for the development of individual centres' internal protocols, serving as a reference for nursing care. METHODS: We review the available evidence on acute stroke care. The most recent national and international guidelines were consulted. Levels of evidence and degrees of recommendation are based on the Oxford Centre for Evidence-Based Medicine classification. RESULTS: The study describes prehospital acute stroke care, the operation of the code stroke protocol, care provided by the stroke team upon the patient's arrival at hospital, reperfusion treatments and their limitations, admission to the stroke unit, nursing care in the stroke unit, and discharge from hospital. CONCLUSIONS: These guidelines provide general, evidence-based recommendations to guide professionals who care for patients with acute stroke. However, limited data are available on some aspects, showing the need for continued research on acute stroke management.


Asunto(s)
Atención de Enfermería , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular/terapia , Hospitalización , Hospitales , Derivación y Consulta
4.
Ann Vasc Surg ; 73: 86-96, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33493590

RESUMEN

OBJECTIVES: To analyze the outcome of vascular procedures performed in patients with COVID-19 infection during the 2020 pandemic. METHODS: This is a multicenter, prospective observational cohort study. We analyzed data from 75 patients with COVID-19 infection undergoing vascular surgery procedures in 17 hospitals across Spain and Andorra between March and May 2020. The primary end point was 30-day mortality. Clinical Trials registry number NCT04333693. RESULTS: The mean age was 70.9 (45-94) and 58 (77.0%) patients were male. Around 70.7% had postoperative complications, 36.0% of patients experienced respiratory failure, 22.7% acute renal failure, and 22.7% acute respiratory distress syndrome (ARDS). All-cause 30-days mortality rate was 37.3%. Multivariate analysis identified age >65 years (P = 0.009), American Society of Anesthesiologists (ASA) classification IV (P = 0.004), preoperative lymphocyte count <0.6 (×109/L) (P = 0.001) and lactate dehydrogenase (LDH) >500 (UI/L) (P = 0.004), need for invasive ventilation (P = 0.043), postoperative acute renal failure (P = 0.001), ARDS (P = 0.003) and major amputation (P = 0.009) as independent variables associated with mortality. Preoperative coma (P = 0.001), quick Sepsis Related Organ Failure Assessment (qSOFA) score ≥2 (P = 0.043), lymphocytes <0.6 (×109/L) (P = 0.019) leucocytes >11.5 (×109/L) (P = 0.007) and serum ferritin >1800 mg/dL (P = 0.004), bilateral lung infiltrates on thorax computed tomography (P = 0.025), and postoperative acute renal failure (P = 0.009) increased the risk of postoperative ARDS. qSOFA score ≥2 was the only risk factor associated with postoperative sepsis (P = 0.041). CONCLUSIONS: Patients with COVID-19 infection undergoing vascular surgery procedures showed poor 30-days survival. Age >65 years, preoperative lymphocytes <0.6 (x109/L) and LDH >500 (UI/L), and postoperative acute renal failure, ARDS and need for major amputation were identified as prognostic factors of 30-days mortality.


Asunto(s)
COVID-19/complicaciones , Complicaciones Posoperatorias/epidemiología , Procedimientos Quirúrgicos Vasculares/efectos adversos , Lesión Renal Aguda/etiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Andorra/epidemiología , COVID-19/mortalidad , Estudios de Cohortes , Femenino , Humanos , L-Lactato Deshidrogenasa/sangre , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/mortalidad , Pronóstico , Síndrome de Dificultad Respiratoria/etiología , Factores de Riesgo , España/epidemiología , Resultado del Tratamiento
5.
Neurologia (Engl Ed) ; 2020 Nov 02.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33153769

RESUMEN

OBJECTIVE: This study provides a series of updated, evidence-based recommendations for the management of acute stroke. We aim to lay a foundation for the development of individual centres' internal protocols, serving as a reference for nursing care. METHODS: We review the available evidence on acute stroke care. The most recent national and international guidelines were consulted. Levels of evidence and degrees of recommendation are based on the Oxford Centre for Evidence-Based Medicine classification. RESULTS: The study describes prehospital acute stroke care, the operation of the code stroke protocol, care provided by the stroke team upon the patient's arrival at hospital, reperfusion treatments and their limitations, admission to the stroke unit, nursing care in the stroke unit, and discharge from hospital. CONCLUSIONS: These guidelines provide general, evidence-based recommendations to guide professionals who care for patients with acute stroke. However, limited data are available on some aspects, showing the need for continued research on acute stroke management.

7.
Cell Death Dis ; 5: e1185, 2014 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-24743740

RESUMEN

Met, the tyrosine kinase receptor for hepatocyte growth factor (HGF), mainly activates prosurvival pathways, including protection from apoptosis. In this work, we investigated the cardioprotective mechanisms of Met activation by agonist monoclonal antibodies (mAbs). Cobalt chloride (CoCl2), a chemical mimetic of hypoxia, was used to induce cardiac damage in H9c2 cardiomyoblasts, which resulted in reduction of cell viability by (i) caspase-dependent apoptosis and (ii) - surprisingly - autophagy. Blocking either apoptosis with the caspase inhibitor benzyloxycarbonyl-VAD-fluoromethylketone or autophagosome formation with 3-methyladenine prevented loss of cell viability, which suggests that both processes contribute to cardiomyoblast injury. Concomitant treatment with Met-activating antibodies or HGF prevented apoptosis and autophagy. Pro-autophagic Redd1, Bnip3 and phospho-AMPK proteins, which are known to promote autophagy through inactivation of the mTOR pathway, were induced by CoCl2. Mechanistically, Met agonist antibodies or HGF prevented the inhibition of mTOR and reduced the flux of autophagosome formation. Accordingly, their anti-autophagic function was completely blunted by Temsirolimus, a specific mTOR inhibitor. Targeted Met activation was successful also in the setting of low oxygen conditions, in which Met agonist antibodies or HGF demonstrated anti-apoptotic and anti-autophagic effects. Activation of the Met pathway is thus a promising novel therapeutic tool for ischaemic injury.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Cardiotónicos/farmacología , Citoprotección/efectos de los fármacos , Miocitos Cardíacos/patología , Proteínas Proto-Oncogénicas c-met/agonistas , Animales , Línea Celular , Cobalto , Factor de Crecimiento de Hepatocito/farmacología , Miocitos Cardíacos/efectos de los fármacos , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-met/metabolismo , Ratas , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo
8.
Cell Mol Life Sci ; 71(8): 1439-52, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24218009

RESUMEN

MicroRNAs (miRNAs) are natural, single-stranded, small RNA molecules which subtly control gene expression. Several studies indicate that specific miRNAs can regulate heart function both in development and disease. Despite prevention programs and new therapeutic agents, cardiovascular disease remains the main cause of death in developed countries. The elevated number of heart failure episodes is mostly due to myocardial infarction (MI). An increasing number of studies have been carried out reporting changes in miRNAs gene expression and exploring their role in MI and heart failure. In this review, we furnish a critical analysis of where the frontier of knowledge has arrived in the fields of basic and translational research on miRNAs in cardiac ischemia. We first summarize the basal information on miRNA biology and regulation, especially concentrating on the feedback loops which control cardiac-enriched miRNAs. A focus on the role of miRNAs in the pathogenesis of myocardial ischemia and in the attenuation of injury is presented. Particular attention is given to cardiomyocyte death (apoptosis and necrosis), fibrosis, neovascularization, and heart failure. Then, we address the potential of miR-diagnosis (miRNAs as disease biomarkers) and miR-drugs (miRNAs as therapeutic targets) for cardiac ischemia and heart failure. Finally, we evaluate the use of miRNAs in the emerging field of regenerative medicine.


Asunto(s)
Retroalimentación Fisiológica/fisiología , Regulación de la Expresión Génica/genética , Terapia Genética/métodos , MicroARNs/uso terapéutico , Isquemia Miocárdica/genética , Isquemia Miocárdica/terapia , Miocitos Cardíacos/fisiología , Apoptosis/fisiología , Humanos , MicroARNs/genética , Isquemia Miocárdica/fisiopatología , Necrosis/fisiopatología , Neovascularización Fisiológica/fisiología , Medicina Regenerativa/tendencias
9.
Ann Ig ; 25(1): 83-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23435783

RESUMEN

Zoonoses have been and are still considered merely a "veterinary problem". Instead, the understanding of their emergence, re-emergence and persistence is more effectively addressed in the context of a "struggle" between pathogens, animals and man. The expression properties of pathogens are related with three interfaces: human-environment, environment-animal and human-animal. Animals and man can be either reservoirs or vectors of pathogens, while interfaces can amplify the clinical impact in all the species involved. The disease course is similar in animals and humans in terms of infection, clinical approach and control. Thus, this "epidemiological model" may be the key to an "updated" interpretation of infectious diseases involving humans and animals. Control and prevention should be carried out in an interdisciplinary context, without separating the medical and veterinary domains, in light of the fact that the activity of pathogenic microorganisms is not species-dependent. Finally, if human public health and veterinary public health are closely linked, knowledge and information can be pooled and used for mutual benefit.


Asunto(s)
Enfermedades Transmisibles Emergentes , Zoonosis , Animales , Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/etiología , Enfermedades Transmisibles Emergentes/prevención & control , Humanos , Zoonosis/epidemiología , Zoonosis/transmisión
10.
Science ; 332(6034): 1167-70, 2011 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-21636766

RESUMEN

A quantum fluid passing an obstacle behaves differently from a classical one. When the flow is slow enough, the quantum gas enters a superfluid regime, and neither whirlpools nor waves form around the obstacle. For higher flow velocities, it has been predicted that the perturbation induced by the defect gives rise to the turbulent emission of quantized vortices and to the nucleation of solitons. Using an interacting Bose gas of exciton-polaritons in a semiconductor microcavity, we report the transition from superfluidity to the hydrodynamic formation of oblique dark solitons and vortex streets in the wake of a potential barrier. The direct observation of these topological excitations provides key information on the mechanisms of superflow and shows the potential of polariton condensates for quantum turbulence studies.

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