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1.
Phys Rev Lett ; 124(11): 110604, 2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-32242716

RESUMEN

We use a near quantum limited detector to experimentally track individual quantum state trajectories of a driven qubit formed by the hybridization of a waveguide cavity and a transmon circuit. For each measured quantum coherent trajectory, we separately identify energy changes of the qubit as heat and work, and verify the first law of thermodynamics for an open quantum system. We further establish the consistency of these results by comparison with the master equation approach and the two-projective-measurement scheme, both for open and closed dynamics, with the help of a quantum feedback loop that compensates for the exchanged heat and effectively isolates the qubit.

2.
Phys Rev Lett ; 121(3): 030604, 2018 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-30085766

RESUMEN

We use continuous weak measurements of a driven superconducting qubit to experimentally study the information dynamics of a quantum Maxwell's demon. We show how information gained by a demon who can track single quantum trajectories of the qubit can be converted into work using quantum coherent feedback. We verify the validity of a quantum fluctuation theorem with feedback by utilizing information obtained along single trajectories. We demonstrate, in particular, that quantum backaction can lead to a loss of information in imperfect measurements. We furthermore probe the transition between information gain and loss by varying the initial purity of the qubit.

3.
Transplant Proc ; 39(7): 2393-6, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17889200

RESUMEN

OBJECTIVE: Bone loss and bone fractures are disabling complications after heart transplantation. Severe bone loss happens mainly during the first year posttransplantation. Steroids and cyclosporine alter bone metabolism in several ways. To counterbalance these effects, antiresorptive therapy is provided to these patients. The objective of this study was to assess the frequency of bone fractures after heart transplantation, considering previous comorbidities, immunosuppressive therapy, and osteoprotective treatment. METHODS: From 1993 to 2005, 443 consecutive heart transplant recipients were followed for the occurrence of bone fractures, immunosuppressive therapy, clinical conditions, and antiresorptive treatment. RESULTS: There were 41 fractures in 34 patients (7.6%, group I). The remainder of patients formed group II. Fractures commonly involved the lumbar spine. Postmenopausal women had more fractures than other patients (20.6% vs 7.8%, P = .02). When the initial immunosuppressive regimen included tacrolimus, fractures did not happen (P = .01, vs other regimens). Osteoprotective therapy was administered to 91.2% of patients in group I and 79% in group II (P = .08). Mean interval from transplantation to the first fracture was 1131.5 days. Overweight patients had a 61.8% incidence of fracture. CONCLUSIONS: Our series showed a low frequency of bone fractures. Postmenopausal women and overweight patients had more fractures. An initial immunosuppressive regimen using tacrolimus was associated with lower fracture rates.


Asunto(s)
Fracturas Óseas/epidemiología , Trasplante de Corazón/efectos adversos , Resorción Ósea/epidemiología , Femenino , Estudios de Seguimiento , Trasplante de Corazón/inmunología , Humanos , Inmunosupresores/uso terapéutico , Incidencia , Masculino , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Factores de Tiempo
4.
Clin Transl Oncol ; 19(1): 91-104, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27101413

RESUMEN

PURPOSE: While much progress has been made in the treatment of breast cancer, cardiac complications resulting from therapy remain a significant concern. Both anthracyclines and novel targeted agents can inflict cardiac damage. The present study aimed to evaluate the difference between what it is currently done and what standards of care should be used to minimizing and managing cardiac toxicity in breast cancer survivors. METHODS: A two-round multicenter Delphi study was carried out. The panel consisted of 100 oncologists who were asked to define the elected therapies for breast cancer patients, the clinical definition and patterns of cancer drug-derived cardiac toxicity, and those protocols focused on early detection and monitoring of cardiovascular outcomes. RESULTS: Experts agreed a more recent definition of cardiotoxicity. Around 38 % of patients with early-stage disease, and 51.3 % cases with advanced metastatic breast cancer had preexisting risk factors for cardiotoxicity. Among risk factors, cumulative dose of anthracycline ≥450 mg/m2 and its combination with other anticancer drugs, and a preexisting cardiovascular disease were considered the best predictors of cardiotoxicity. Echocardiography and radionuclide ventriculography have been the proposed methods for monitoring changes in cardiac structure and function. Breast cancer is generally treated with anthracyclines (80 %), so that the panel strongly stated about the need to plan a strategy to managing cardiotoxicity. A decline of left ventricular ejection fraction (LVEF) >10 %, to an LVEF value <53 % was suggested as a criterion for changing the dose schedule of anthracyclines, or suspending the treatment of chemotherapy plus trastuzumab until the normalization of the left ventricular function. The use of liposomal anthracyclines was strongly suggested as a treatment option for breast cancer patients. CONCLUSIONS: The present report is the first to produce a set of statements on the prevention, evaluation and monitoring of chemotherapy-induced cardiac toxicity in breast cancer patients.


Asunto(s)
Antraciclinas/efectos adversos , Antineoplásicos/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Cardiotoxicidad/etiología , Cardiotoxicidad/prevención & control , Técnica Delphi , Función Ventricular Izquierda/efectos de los fármacos , Anciano , Femenino , Estudios de Seguimiento , Humanos , Estadificación de Neoplasias , Pronóstico , Factores de Riesgo
5.
J Agric Food Chem ; 54(12): 4326-32, 2006 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-16756363

RESUMEN

An HPLC-MS method for the characterization of proanthocyanidins (PA) has been refined. Further application to red wines provided interesting conclusions about the composition of the flavanol fraction and PA extractability during winemaking. The yield in PA extraction increases with the length of the postfermentative maceration (PFM), as well as the mean degree of polymerization (mDP) of wine flavanols. In early winemaking events mostly monomers to trimers are extracted from grape solids, whereas PFM is required for the significant extraction of higher oligomers. Nevertheless, at the end of a regular process of elaboration the mDP is not very high and does not usually exceed a value of 2.3, dimers and trimers being the predominant flavanols in red wines. With regard to groups of compounds, gallocatechins and prodelphinidins (located in the skins) are extracted rapidly in the first stages of the winemaking. On the contrary, long postfermentative macerations are required for the extraction of galloyled derivatives from the seeds. PA extractability is also dependent on the grape variety used for winemaking. Thus, wines made with Graciano grapes were found to require a longer process of PFM than those made from Tempranillo grapes to obtain similar yields in the extraction of flavanols.


Asunto(s)
Cromatografía Líquida de Alta Presión , Espectrometría de Masas , Polímeros/análisis , Proantocianidinas/química , Vino/análisis , Fermentación , Flavonoides/análisis , Frutas/química , Polímeros/química , Proantocianidinas/análisis , Especificidad de la Especie , Factores de Tiempo , Vitis/química
6.
J Am Coll Cardiol ; 27(1): 22-9, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8522699

RESUMEN

OBJECTIVES: This study was designed to evaluate the effect of an antithrombotic regimen without full early anticoagulation on subacute occlusion, bleeding, hospital stay and restenosis after elective coronary stenting. BACKGROUND: Subacute occlusion is a major limitation of stenting. Aggressive antithrombotic therapy is not fully prophylactic against this complication, carries risk of bleeding, prolongs hospital stay and reduces cost-effectiveness. METHODS: We studied 110 consecutive patients (121 lesions) who underwent elective Palmaz-Schatz stenting. Intravenous heparin was given only during the procedure. After stenting, patients took aspirin, dipyridamole, dextran, warfarin and low molecular weight heparin (enoxaparin, 40 mg subcutaneously daily, stopped when an international normalized ratio of 2 to 3 was achieved). The first 52 patients (group A) underwent coronary angiography 24 h after stenting, and hospital stay was extended until an international normalized ratio of 2 to 3.5 was achieved. The remaining 58 patients (group B) were discharged 24 h after stenting. Clinical and angiographic follow-up were performed 1 and 6 months after stenting for all patients. RESULTS: In group A the activated partial thromboplastin time remained normal (30 +/- 6.2 s [mean +/- SD]) during enoxaparin administration, and hospital stay was 9.1 +/- 4.3 days. In group B hospital stay was 27 +/- 8 h. No major cardiac events occurred within the first month in patients from both groups. At 1 and 30 days all stented lesions remained patent. Only two patients (1.8%, 95% confidence interval [CI] 0.32% to 7%) developed bleeding. At 6 months, the restenosis rate was 22% (95% CI 15% to 30%). CONCLUSIONS: After coronary stenting with optimal angiographic results, this new antithrombotic regimen prevented subacute stent occlusion and bleeding, with a brief hospital stay. No detrimental effect on the previously reported restenosis rate was observed.


Asunto(s)
Anticoagulantes/uso terapéutico , Enfermedad Coronaria/terapia , Stents/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Aspirina/uso terapéutico , Angiografía Coronaria , Enfermedad Coronaria/diagnóstico por imagen , Dextranos/uso terapéutico , Dipiridamol/uso terapéutico , Femenino , Hemorragia/etiología , Heparina/uso terapéutico , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Tiempo de Tromboplastina Parcial , Inhibidores de Agregación Plaquetaria/uso terapéutico , Estudios Prospectivos , Recurrencia , Warfarina/uso terapéutico
7.
J Agric Food Chem ; 49(3): 1260-3, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11312846

RESUMEN

This paper reports the composition of total fatty acids in an apple beverage, cider. Fatty acids are present in the free or esterified form and contribute to both the flavor and foam properties of cider. Fatty acids were separated and identified as methyl esters by GC-MS, and 12 of these were subsequently determined by GC-FID. The major fatty acids found in cider were caproic, caprylic, capric, and palmitic acid, the saturated acids predominating over the unsaturated ones. The proposed method was applied to 59 ciders from three consecutive harvests (1996, 1997, and 1998), which were made by 19 cider-makers from the region of Asturias (Spain). Linear discriminant analysis of fatty acids in these samples allowed selection of palmitoleic, pentadecanoic, linoleic, myristic, and linolenic acid as the most predictive variables to differentiate ciders made from apples grown in the Asturias region (1997 harvest) and ciders made from apples grown outside this region (1996 and 1998 harvests).


Asunto(s)
Bebidas/análisis , Ácidos Grasos no Esterificados/análisis , Ácidos Grasos/análisis , Frutas/química , Cromatografía de Gases/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos
8.
J Physiol Biochem ; 56(3): 231-6, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11198160

RESUMEN

In order to obtain healthier goat milk as far as its fat composition is concerned, milk production and composition trials were carried out with Granadina goats kept in semi-extensive breeding conditions. The animals were feeding indoors with a concentrate supplemented or not with 7% of fat conveniently protected against the action of rumen, which had 35% of polyunsaturated fatty acids (PUFA). The amount of milk produced was higher (p < 0.05) with consumption of the fat supplemented concentrate. At the same time, and although there was no difference in the milk concentration of fat and protein nitrogen (p > 0.05), the corresponding yields were higher for consumption of the fat supplemented concentrate. As for the composition of milk fat, the use of the supplemented concentrate resulted in fat with a higher (p < 0.05) concentration of PUFA and a lower (p < 0.05) concentration of stearic acid. At the same time, the concentration of medium chain triglycerides, which is the specific nutritional value particular to goats' milk, was the same whichever concentrate was consumed.


Asunto(s)
Industria Lechera/métodos , Ácidos Grasos Insaturados/farmacocinética , Leche/química , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Ingestión de Alimentos , Ácidos Grasos Insaturados/análisis , Femenino , Cabras , Rumen/metabolismo , Ácidos Esteáricos/análisis
9.
Rev Esp Cardiol ; 53(2): 218-40, 2000 Feb.
Artículo en Español | MEDLINE | ID: mdl-10734755

RESUMEN

Interventional cardiology has had an extraordinary expansion in last years. This clinical guideline is a review of the scientific evidence of the techniques in relation to clinical and anatomic findings. The review includes: 1. Coronary arteriography. 2. Coronary balloon angioplasty. 3. Coronary stents. 4. Other techniques: directional atherectomy, rotational atherectomy, transluminal extraction atherectomy, cutting balloon, laser angioplasty and transmyocardial laser and endovascular radiotherapy. 5. Platelet glycoprotein IIb/IIIa inhibitors. 6. New diagnostic techniques: intravascular ultrasound, coronary angioscopy, Doppler and pressure wire. For the recommendations we have used the classification system: class I, IIa, IIb, III like in the guidelines of the American College of Cardiology and the American Heart Association.


Asunto(s)
Angioplastia Coronaria con Balón/normas , Aterectomía Coronaria/normas , Cardiología/normas , Angioplastia Coronaria con Balón/métodos , Aterectomía Coronaria/métodos , Cardiología/métodos , Técnicas de Diagnóstico Cardiovascular/normas , Humanos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/antagonistas & inhibidores , España , Stents
10.
Rev Esp Cardiol ; 53(2): 241-66, 2000 Feb.
Artículo en Español | MEDLINE | ID: mdl-10734756

RESUMEN

Surgery in coronary disease, including myocardial revascularization and the surgery of mechanical complications of acute myocardial infarction, has shown to improve the symptoms, quality of life and/or prognosis in certain groups of patients. The expected benefit in each patient depend on many well-known factors among which the appropriateness of the indication for surgery is fundamental. The objective of these guidelines is to review current indications for cardiac surgery in patients with coronary heart disease through an evaluation of the degree of evidence of effectiveness in the light of current knowledge (systematic review of bibliography) and expert opinion gathered from various reports. Indications and the degree of recommendation for conventional coronary artery bypass grafting have been established for each of the most frequent anatomo-clinical situations defined by clinical symptoms (stable angina, unstable angina and acute myocardial infarction) as well as by left ventricular function and extend of coronary disease. Furthermore, the subgroups with the greatest surgical risk and stratification models are described to aid the decision making process. Also we analyse the rational basis and indication for the new surgical techniques such as minimally invasive coronary surgery and total arterial revascularization. Finally, the indication and timing of surgery in patients with mechanical complications of acute myocardial infarction are considered.


Asunto(s)
Cardiología/normas , Enfermedad Coronaria/cirugía , Revascularización Miocárdica/normas , Cardiología/métodos , Humanos , Revascularización Miocárdica/métodos , Selección de Paciente , Factores de Riesgo , España
11.
Rev Esp Cardiol ; 52 Suppl 1: 131-40, 1999.
Artículo en Español | MEDLINE | ID: mdl-10364822

RESUMEN

Pharmacological treatment frequently stabilizes symptoms of patients with acute myocardial ischemia. However, significant quiescent residual stenosis normally persists and leads to rethrombosis. Since rethrombosis produces reischemia and has a deleterious impact on initial and long-term prognosis in these patients, definitive normalisation of local flow assured through deactivation treatments and complete passivation of quiescent residual stenosis in an inert plaque should be a main priority in modern treatment of acute coronary ischemia. Considering the negative influence of significant stenosis on rethrombosis, and that the normalization has a clear antithrombotic effect of flow, routine elimination of residual stenosis by means of angioplasty should prevent rethrombosis and its side effects. Nevertheless, according to trials carried out previous to the most relevant progresses in the field of interventional cardiology, the advantage of this strategy over the conservative treatment has not been clearly demonstrated. Coronary stenting produces a real normalisation of flow and lumen which prevents local thrombosis. In concordance with these facts, recent evidence indicates a substancial clinical benefit of stenting in very thrombogenic acute settings, such as primary angioplasty or refractory acute coronary angina. Presumably, routine stenting also benefits initial and long-term prognosis of other subsets of unstable patients, especially those with thrombolysed myocardial infarction and stabilized patients with acute ischemia without ST-segment elevation. To demonstrate this new trials are needed to compare the efficacy of conservative and interventional approaches that incorporate the advances of each strategys. Until new data are available on these studies, the treatment of acute coronary ischemia should be tailored to each patient and no out-dated recommendation should be given or accepted.


Asunto(s)
Angioplastia Coronaria con Balón , Enfermedad Coronaria/terapia , Stents , Enfermedad Aguda , Ensayos Clínicos como Asunto , Enfermedad Coronaria/tratamiento farmacológico , Humanos , Síndrome
12.
Rev Esp Cardiol ; 52(4): 237-44, 1999 Apr.
Artículo en Español | MEDLINE | ID: mdl-10217964

RESUMEN

BACKGROUND AND PURPOSE: The identification of patients at risk for future events after an infarction is mandatory. The aim of this study was to assess the prognostic value of dobutamine stress echocardiography after an uncomplicated myocardial infarction. METHODS: One hundred and twenty five patients (mean age 65 +/- 11 years, males 82%) underwent dobutamine-echo within ten days after an uncomplicated myocardial infarction. Four myocardial responses were identified: a) negative; b) sustained improvement of myocardial contractility; c) initial improvement followed by worsening, and d) worsening at a distance or in the infarcted zone. RESULTS: Mean follow-up was 7.4 +/- 4.6 months. An adverse outcome occurred in 47 patients: non cardiac death in 3, cardiac death in 6, myocardial infarction in 5, angina in 21, congestive heart failure in 2, and in 10 patients revascularization. Cox regression analysis showed that worsening of contractility was the best predictor for adverse events (p < 0.0001, relative risk 2.8; 95% confidence interval: 1.7-4.5). Non-smoking and previous angina were also predictors of adverse events (p = 0.003 and p = 0.04, respectively). Similar results were obtained after excluding the revascularized patients. CONCLUSIONS: Sustained improvement of contractility in the infarcted region is not a predictor of adverse events. Asynergy at a distance or in the infarcted region during dobutamine echocardiography within ten days after an uncomplicated myocardial infarction predicts adverse cardiac events during follow-up. Therefore, dobutamine echocardiography could be used for risk stratification after acute myocardial infarction.


Asunto(s)
Cardiotónicos , Dobutamina , Ecocardiografía/métodos , Prueba de Esfuerzo/métodos , Infarto del Miocardio/diagnóstico por imagen , Anciano , Análisis de Varianza , Cardiotónicos/administración & dosificación , Dobutamina/administración & dosificación , Ecocardiografía/estadística & datos numéricos , Prueba de Esfuerzo/estadística & datos numéricos , Femenino , Estudios de Seguimiento , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Factores de Riesgo , Factores de Tiempo
13.
Rev Esp Cardiol ; 52(11): 919-56, 1999 Nov.
Artículo en Español | MEDLINE | ID: mdl-10611807

RESUMEN

In the recent years, new possibilities have emerged in the diagnosis and management of acute myocardial infarction with ST segment elevation and its complications. Moreover, a deep transformation has taken place in the health care system organization, particularly in aspects related to care of patients presenting non-traumatic chest pain, both in pre-hospital and hospital areas. All these issues warrant a consensus document in Spain dealing with the role that these important changes should play in the whole management of myocardial infarction patients. This document revises and updates all the main clinical issues of acute myocardial infarction patients from the moment they contact with the health care system outside the hospital until they return home, after staying at the coronary care unit and the general hospitalization ward. All those aspects are considered not only in the uncomplicated myocardial infarction but also in the complicated one. This review also includes a set of recommendations on structural and organisational aspects, mainly referred to the prehospital and emergency levels.


Asunto(s)
Infarto del Miocardio/diagnóstico , Infarto del Miocardio/tratamiento farmacológico , Cardiología , Enfermedad Coronaria/clasificación , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/tratamiento farmacológico , Electrocardiografía , Humanos , Infarto del Miocardio/clasificación , Infarto del Miocardio/complicaciones , Planificación de Atención al Paciente , Factores de Riesgo , España , Terapia Trombolítica/métodos
15.
Mar Pollut Bull ; 64(11): 2471-9, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22921898

RESUMEN

An in-depth knowledge of solutes advection and turbulent diffusion is crucial to estimate dispersion area and retention time (t(R)) of pollutants within seagrass habitats. However, there is little knowledge on the influence of seagrass habitat fragmentation on such mechanisms. A set of dye tracer experiments and acoustic Doppler velocimeter measurements (ADV) were conducted. Solute transport conditions were compared in between fragmented (FM) vs homogeneous (HM) intertidal meadows, and in vertical gradients (canopy vs overlaying flow). Results showed the highest horizontal diffusion coefficient (K(y), c.a. 10(-3)m(2)s(-1)) on FM and at the canopy-water column interface, whereas t(R) (2.6-5.6 min) was not affected by fragmentation. It suggests that (1) FM are more vulnerable to pollution events in terms of dispersion area and (2) at low tide, advection rather than turbulent diffusion determines t(R). Furthermore, Taylor's theorem is revealed as a powerful tool to analyze vertical gradients on K(y) within seagrass canopies.


Asunto(s)
Ecosistema , Monitoreo del Ambiente , Contaminantes del Agua/análisis , Zosteraceae , Sedimentos Geológicos/análisis , Modelos Químicos , Movimientos del Agua , Contaminación del Agua/estadística & datos numéricos
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