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1.
Phys Chem Chem Phys ; 26(4): 3117-3125, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38189473

RESUMEN

Icosahedral Ni13@Ag42 is a stable nanoparticle formed by a magnetic nickel core surrounded by a silver coating that provides physical protection to the 3d metal cluster as well as antibacterial properties. In this work, we report density functional theoretical calculations to delve into a comprehensive analysis of how surface oxidation impacts the structural, electronic, magnetic, and reactivity properties of this interesting nanoparticle. To elucidate the role played by the silver coating, we compare the results with those found for the bare Ni13 cluster also subjected to surface oxidation. When Ni13 is covered by silver, we find a markedly robust behavior of the magnetic moment of the resulting nanoparticle, which remains nearly constant upon oxidation up to the rates explored, and the same holds for its overall reactivity. The obtained trends are rationalized in terms of the complex interplay between Ni-Ag and Ag-O interactions which impact the relative inter-atomic distances, charge transfer effects, spin polarization and magnetic couplings.

2.
Nanoscale Adv ; 5(10): 2813-2819, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37205290

RESUMEN

Iron ilmenene is a new two-dimensional material that has recently been exfoliated from the naturally occurring iron titanate found in ilmenite ore, a material that is abundant on the earth's surface. In this work, we theoretically investigate the structural, electronic and magnetic properties of 2D transition-metal-based ilmenene-like titanates. The study of magnetic order reveals that these ilmenenes usually present intrinsic antiferromagnetic coupling between the 3d magnetic metals decorating both sides of the Ti-O layer. Furthermore, the ilmenenes based on late 3d brass metals, such as CuTiO3 and ZnTiO3, become ferromagnetic and spin compensated, respectively. Our calculations which include spin-orbit coupling reveal that the magnetic ilmenenes have large magnetocrystalline anisotropy energies when the 3d shell departs from being either filled or half-filled, with their spin orientation being out-of-plane for elements below half-filling of 3d states and in-plane above. These interesting magnetic properties of ilmenenes make them useful for future spintronic applications because they could be synthesized as already realized in the iron case.

3.
Phys Chem Chem Phys ; 23(43): 24685-24698, 2021 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-34708842

RESUMEN

ZnMg alloys of certain compositions in the Zn-rich side of the phase diagram are particularly efficient, and widely used, as anticorrosive coatings, but a sound understanding of the physico-chemical properties behind such quality is still far from being achieved. The present work focuses on the first stage of the corrosion process, namely the initial growth of a sacrificial surface oxide layer, whose characteristics will condition the next stages of the corrosion. A comprehensive ab initio study, based on density functional theory, is carried out on ZnMg nanoalloys with 20 atoms and different compositions, which serve as model systems to simulate the complex processes that occur in extended granular surfaces. The structural and electronic properties, when progressive oxidation of the nanoalloys takes place, are analyzed in detail with the help of structural descriptors, energetic descriptors such as the oxygen adsorption energies and excess adsorption energies, as well as with electronic ones based on the topological analysis of the electron density and the electron localization function, from which a detailed analysis of the bonding patterns is extracted. We explain why small amounts of Mg create a very positive synergy between Zn and Mg that increases the reactivity to oxygen while reducing, at the same time, the stress induced on the cluster substrate, both facts working in favor of promoting the growth of the oxide crust whilst protecting the core. Moreover, we also show that stoichiometries close to the Mg2Zn11 and MgZn2 compositions are the best candidates to optimize the protection against corrosion in Zn-Mg alloys, in agreement with the experimental observations.

4.
J Electrocardiol ; 68: 48-52, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34333405

RESUMEN

INTRODUCTION: Acute total occlusion of the left main coronary artery (ATOLMA) usually leads to a catastrophic presentation. Prediction of ATOLMA by electrocardiogram (ECG) may contribute to early detection and reperfusion. Limited data have been reported previously. This study aims to identify the admission 12­leads ECG features that can predict the presence of ATOLMA and in-Hospital mortality in these patients. METHODS: The admission ECGs findings in 24 patients from the previously reported ATOLMA multicenter registry were compared to the ECGs findings in 15 patients with an acute subtotal occlusion of the left main (ASOLMA) and to 15 patients with anterior ST-elevation myocardial infarction of the proximal left anterior descending (LADp-STEMI). RESULTS: Some ECG features at presentation can predict an ATOLMA: QRS left axis deviation (-61.17 ± 9 degrees); ST-segment elevation in aVL (1.9 ± 0.65 mm); absence of ST-segment elevation in V1 (0.0 ± 0.6 mm); bifascicular block (58%); fragmented QRS (62.5%); prolongation of QTc interval (465 ± 19 ms) and of QRS interval (136 ± 12 mm). The multivariate analysis found that the independent predictors to distinguish ATOLMA from ASOLMA were aVL ST-segment deviation (OR 5.6(95% CI 1.5-21), p = 0.01) and absence of V1 ST-segment elevation (OR 27(95% CI 1.4-52), p = 0.01); and from LADp-STEMI was QRS width (OR 1.1(95% CI 1.02-1.2), p = 0.02). Fragmented QRS was the only independent predictor of in-hospital mortality in ATOLMA (OR 0.125(95% CI 0.01-0.81), p = 0.03). CONCLUSIONS: aVL ST-segment elevation, the absence of V1 ST-segment elevation, left axis deviation, the presence of bifascicular block, and prolongation of QRS and QTc interval are predictors of ATOLMA. Fragmented QRS predicts in-hospital mortality in ATOLMA.


Asunto(s)
Oclusión Coronaria , Infarto del Miocardio , Bloqueo de Rama , Oclusión Coronaria/diagnóstico , Electrocardiografía , Humanos , Sistema de Registros
5.
Phys Chem Chem Phys ; 23(1): 246-272, 2021 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-33325468

RESUMEN

Due to quantum confinement effects, the understanding of iron oxide nanoparticles is a challenge that opens the possibility of designing nanomaterials with new capacities. In this work, we report a theoretical density functional theory study of the structural, electronic, and magnetic properties of neutral and charged iron oxide clusters FenOm0/± (n = 1-6), with m values until oxygen saturation is achieved. We determine the putative ground state configuration and low-energy structural and spin isomers. Based on the total energy differences between the obtained global minimum structure of the parent clusters and their possible fragments, we explore the fragmentation channels for cationic oxides, comparing with experiments. Our results provide fundamental insight on how the structural pattern develops upon oxidation and its connection with the magnetic couplings and net total moment. Upon addition of oxygen, electronic charge transfer from iron to oxygen is found which weakens the iron-iron bond and consequently the direct exchange coupling in Fe. The binding energy increases as the oxygen ratio increases, rising faster at low oxidation rates. When molecular oxygen adsorption starts to take place, the binding energy increases more slowly. The oxygen environment is a crucial factor related to the stabilities and to the magnetic character of iron oxides. We identified certain iron oxide clusters of special relevance in the context of magnetism due to their high stability, expected abundance and parallel magnetic couplings that cause large total magnetic moments even at high oxidation ratios.

6.
Rev. chil. pediatr ; 91(6): 982-990, dic. 2020. ilus, tab
Artículo en Español | LILACS | ID: biblio-1508061

RESUMEN

Desde la aparición de la pandemia por SARS-CoV-2, la población pediátrica ha sido menos afectada por la enfermedad tanto en frecuencia como en severidad. Sin embargo, desde abril de este año se han reportado casos de presentación y gravedad variables, caracterizados por fenómenos inflamato rios que afectan múltiples órganos, condición denominada Síndrome Inflamatorio Multisistémico Pediátrico (PIMS). La literatura describe frecuente compromiso cardíaco, hasta en un 80%. Este se caracteriza por injuria miocárdica con significativa elevación de biomarcadores: Troponinas séricas I/T, BNP o NT-ProBNP, unido a diversos grados de disfunción ventricular, pericarditis, valvulitis y arritmias. Además, se ha evidenciado la presencia de compromiso coronario el cual puede ocurrir hasta en un 23% de los casos, en un rango que va desde dilataciones hasta aneurismas. El seguimien to cardiológico hospitalizado y ambulatorio se ha sistematizado en base a los fenotipos clínicos de presentación: injuria miocárdica (miocarditis, valvulitis, pericarditis), shock (habitualmente de tipo "vasopléjico"), manifestaciones tipo Enfermedad de Kawasaki y aquellos casos PIMS que no cumplen con la clínica de los tres precedentes. Este último grupo es el que representa el mayor desafío en el cor to, mediano y seguimiento a largo plazo. Por esta razón se requiere un equipo multidisciplinario para su manejo. Considerando la alta frecuencia del compromiso cardíaco en el PIMS y la importancia de lograr un consenso en su manejo y seguimiento, se presentan estas recomendaciones según el estado actual del conocimiento de esta patología recientemente descrita.


Since the onset of the SARS-CoV-2 pandemic, the pediatric population has been less affected by the disease both in frequency and severity. However, since April cases of variable presentation and severity characterized by inflammatory phenomena that affect multiple organs have been reported, a condition called Multisystem Inflammatory Syndrome in Children (MIS-C). The literature has reported frequent cardiac involvement, up to 80%. This is characterized by myocardial injury with a significant increase of biomarkers such as serum troponins I and T, BNP, or NT-ProBNP coupled with varying degrees of ventricular dysfunction, pericarditis, valvulitis, and arrhythmias. Coronary compromise has also been described, which can occur in up to 23% of cases, and ranges from dila tations to aneurysms. Inpatient and outpatient cardiology follow-up has been systematized based on the clinical phenotypes such as myocardial injury (myocarditis, valvulitis, pericarditis), shock (usua lly vasoplegic), Kawasaki disease-type manifestations, and those MIS-C that do not comply with the clinic of the previous three. This last group represents the main challenge in the short-, medium- and long-term follow-up, therefore, it is necessary a multidisciplinary team for managing these patients. Considering the high frequency of cardiac compromise in MIS-C, and the importance of reaching a consensus regarding its management and follow-up, we present these recommendations according to the current state of knowledge regarding this recently described pathology.


Asunto(s)
Humanos , Niño , Enfermedades Cardiovasculares/virología , Síndrome de Respuesta Inflamatoria Sistémica/terapia , COVID-19/terapia , Grupo de Atención al Paciente/organización & administración , Choque/terapia , Choque/virología , Biomarcadores/metabolismo , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/terapia , Chile , Síndrome de Respuesta Inflamatoria Sistémica/diagnóstico , Síndrome de Respuesta Inflamatoria Sistémica/fisiopatología , COVID-19/diagnóstico , COVID-19/fisiopatología , Síndrome Mucocutáneo Linfonodular/terapia , Síndrome Mucocutáneo Linfonodular/virología
7.
Nanomaterials (Basel) ; 10(9)2020 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-32932899

RESUMEN

Transition-metal oxide nanoparticles are relevant for many applications in different areas where their superparamagnetic behavior and low blocking temperature are required. However, they have low magnetic moments, which does not favor their being turned into active actuators. Here, we report a systematical study, within the framework of the density functional theory, of the possibility of promoting a high-spin state in small late-transition-metal oxide nanoparticles through alloying. We investigated all possible nanoalloys An-xBxOm (A, B = Fe, Co, Ni; n = 2, 3, 4; 0≤x≤n) with different oxidation rates, m, up to saturation. We found that the higher the concentration of Fe, the higher the absolute stability of the oxidized nanoalloy, while the higher the Ni content, the less prone to oxidation. We demonstrate that combining the stronger tendency of Co and Ni toward parallel couplings with the larger spin polarization of Fe is particularly beneficial for certain nanoalloys in order to achieve a high total magnetic moment, and its robustness against oxidation. In particular, at high oxidation rates we found that certain FeCo oxidized nanoalloys outperform both their pure counterparts, and that alloying even promotes the reentrance of magnetism in certain cases at a critical oxygen rate, close to saturation, at which the pure oxidized counterparts exhibit quenched magnetic moments.

8.
Rev Chil Pediatr ; 91(6): 982-990, 2020 Dec.
Artículo en Español | MEDLINE | ID: mdl-33861837

RESUMEN

Since the onset of the SARS-CoV-2 pandemic, the pediatric population has been less affected by the disease both in frequency and severity. However, since April cases of variable presentation and severity characterized by inflammatory phenomena that affect multiple organs have been reported, a condition called Multisystem Inflammatory Syndrome in Children (MIS-C). The literature has reported frequent cardiac involvement, up to 80%. This is characterized by myocardial injury with a significant increase of biomarkers such as serum troponins I and T, BNP, or NT-ProBNP coupled with varying degrees of ventricular dysfunction, pericarditis, valvulitis, and arrhythmias. Coronary compromise has also been described, which can occur in up to 23% of cases, and ranges from dila tations to aneurysms. Inpatient and outpatient cardiology follow-up has been systematized based on the clinical phenotypes such as myocardial injury (myocarditis, valvulitis, pericarditis), shock (usua lly vasoplegic), Kawasaki disease-type manifestations, and those MIS-C that do not comply with the clinic of the previous three. This last group represents the main challenge in the short-, medium- and long-term follow-up, therefore, it is necessary a multidisciplinary team for managing these patients. Considering the high frequency of cardiac compromise in MIS-C, and the importance of reaching a consensus regarding its management and follow-up, we present these recommendations according to the current state of knowledge regarding this recently described pathology.


Asunto(s)
COVID-19/terapia , Enfermedades Cardiovasculares/virología , Síndrome de Respuesta Inflamatoria Sistémica/terapia , Biomarcadores/metabolismo , COVID-19/diagnóstico , COVID-19/fisiopatología , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/terapia , Niño , Chile , Humanos , Síndrome Mucocutáneo Linfonodular/terapia , Síndrome Mucocutáneo Linfonodular/virología , Grupo de Atención al Paciente/organización & administración , Choque/terapia , Choque/virología , Síndrome de Respuesta Inflamatoria Sistémica/diagnóstico , Síndrome de Respuesta Inflamatoria Sistémica/fisiopatología
9.
Eur Geriatr Med ; 10(3): 483-491, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34652787

RESUMEN

PURPOSE: Degenerative aortic stenosis has become a new valvular epidemic in the last few decades due to its high prevalence in the geriatric population. We sought to analyse factors that could influence earlier hospitalization for congestive heart failure in geriatric patients with moderate-severe degenerative aortic stenosis. METHODS: This investigation was an ambispective cohort study of 104 patients aged 70 years or older with moderate-severe aortic stenosis. Epidemiological, geriatric, clinical, echocardiographic and electrocardiographic variables were collected. During the follow-up, the number of admissions for congestive heart failure and the time elapsed from diagnosis to first admission were recorded. RESULTS: A total of 45.2% of the patients were admitted for congestive heart failure, with a median time to first admission of 3 years (95% CI 1.88-4.25). For patients aged 85 years or older, this median was 8.07 months (95% CI 0.05-1.99). The first admission for congestive heart failure was independently related to frailty (HR 4.46, 95% CI: 1.38-14.41), atrial fibrillation (HR 2.19, 95% CI: 1.01-4.73), a high EuroSCORE (HR 1.03, 95% CI: 1.00-1.05), the affected valvular area (HR 0.11, 95% CI: 0.02-0.47), age (HR 1.11, 95% CI: 1.04-1.18) and renal failure (HR 4.13, 95% CI: 1.46-11.63). The median time to admission for frail patients was 1.08 years (95% CI 0.30-1.86). CONCLUSIONS: In geriatric patients with moderate-severe degenerative aortic stenosis, frailty is an independent marker of early congestive heart failure admission with a powerful and important association.

10.
Rev Chil Pediatr ; 89(3): 361-367, 2018 Jun.
Artículo en Español | MEDLINE | ID: mdl-29999142

RESUMEN

INTRODUCTION: Tetralogy of Fallot (TOF) is the most frequent cyanotic congenital heart disease. Pulmonary regurgitation (PR) and right ventricle (RV) enlargement and dysfunction are the most common long-term complications. Cardiac magnetic resonance (CMR) is the gold standard for RV evaluation. OBJECTIVE: To analyze CMR results in the follow-up of TOF patients. PATIENTS AND METHOD: All CMR performed between 2007 and 2012 in TOF patients with transannular patch (TAP) repair or infundibular widening, and without pulmonary valve replacement (PVR) were included. Pulmonary regurgitant fraction (PRF), ventricular end-diastolic (EDV) and end-systolic volume (ESV), and ejection fraction (EF) were examined. RESULTS: 122 CMR were performed in 114 patients. Average age at CMR was 15.4±7.4 years. 53.3% of them presented severe PR (> 40%). RVEDV was 157.3 ± 38.6 ml/m2, RVESV was 85.3 ± 27 ml/m2 and RVEF was 46.4 ± 7.1%. RVEDV was > 150 ml/ m2 in 48.4% and > 170 ml/m2 in 32.8% of patients. Patients with TAP showed larger RV volumes compared with those with infundibular widening. RVEDV > 170 ml/m2 showed worse RVEF that those with lower RVEDV (47.9 ± 7% vs 43.2 ± 6.4%, p < 0.01). CONCLUSION: Almost half of the pa tients showed significant RV enlargement, demonstrating that the indication of CMR is late in their follow-up. TAP was associated with higher RVEDV and RVESV, but no worse RVEF.


Asunto(s)
Hipertrofia Ventricular Derecha/diagnóstico por imagen , Imagen por Resonancia Magnética , Complicaciones Posoperatorias/diagnóstico por imagen , Tetralogía de Fallot/cirugía , Disfunción Ventricular Derecha/diagnóstico por imagen , Adolescente , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Hipertrofia Ventricular Derecha/etiología , Lactante , Masculino , Estudios Retrospectivos , Tetralogía de Fallot/diagnóstico por imagen , Disfunción Ventricular Derecha/etiología
11.
Burns ; 44(8): 1962-1972, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30005991

RESUMEN

OBJECTIVE: To describe how nursing care is delivered to patients with epidermal necrolysis in burn units/specialized units in Spain and a selection of countries. METHOD: Descriptive cross-sectional study. Data were collected through a structured questionnaire which was sent to nurse managers in all burn units in Spain and a selection of countries. Descriptive statistics was used to summarize the results. RESULTS: All BU/SUs in Spain (n=12) and seven BU/SUs from a selection of countries completed the questionnaire. A lack of specific nursing protocols on Epidermal Necrolysis was observed in most burn units in Spain. Skin cleansing techniques such as showering were only reported by participants from Spain. Use of antiseptics was less frequent in other countries. Conservative skin management was the most extended practice reported by all participants. The use of vaginal molds to prevent synechiae and coverage of the ocular surface with amniotic membrane to minimize sequelae were rarely reported. Pain assessment was not always documented in sedated patients and few participants reported the use of specific scales for this purpose. All nurses agreed in the need for consensus nursing care guidelines on the disease. CONCLUSIONS: Nursing care in patients with epidermal necrolysis varied between burn units in Spain. Differences and similarities were observed when compared with burn units in other countries. Genital and ocular care were outdated in all BU/SUs. Pain assessment documentation was suboptimal. Evidence-based nursing care guidelines were generally demanded by all participants to help reduce mortality and morbidity of this rare and often devastating disease.


Asunto(s)
Personal de Enfermería en Hospital , Guías de Práctica Clínica como Asunto , Síndrome de Stevens-Johnson/enfermería , Adulto , Antiinfecciosos Locales/uso terapéutico , Unidades de Quemados , Canadá , Tratamiento Conservador , Estudios Transversales , Documentación , Femenino , Francia , Alemania , Humanos , Italia , Japón , Masculino , Persona de Mediana Edad , Países Bajos , Evaluación en Enfermería , Dimensión del Dolor , Singapur , Cuidados de la Piel/enfermería , Sudáfrica , España , Encuestas y Cuestionarios , Taiwán , Estados Unidos
12.
Rev. chil. pediatr ; 89(3): 361-367, jun. 2018. tab
Artículo en Español | LILACS | ID: biblio-959534

RESUMEN

INTRODUCCIÓN: La tetralogía de Fallot (TF) es la cardiopatía congénita cianótica más frecuente. La insuficiencia pulmonar (IP) y dilatación del ventrículo derecho (VD) son las complicaciones más frecuentes a largo plazo. La resonancia magnética cardiaca (RMC) es el "gold standard" para la evaluación del VD. OBJETIVO: Analizar la información obtenida de las RMC en el seguimiento de pacientes con TF. PACIENTES Y MÉTODO: Se incluyeron RMC realizadas entre 2007 y 2012 a pacientes con TF, reparados con parche transanular (PTA) o ampliación infundibular (AInf) y sin recambio valvular pulmonar (RVP). La fracción de regurgitación pulmonar (FRP), el volumen y función ventricular fueron evaluados. RESULTADOS: Se realizaron 122 RMC a 114 pacientes. Edad promedio al examen 15,4 ± 7,4 años. 53,3% presentó IP severa (> 40%). La media del volumen de fin de diástole del VD (VFDVD) fue 157,3 ± 38,6 ml/m2, fin de sístole (VFSVD) de 85,3 ± 27 ml/m2 y fracción de eyección (FEVD) 46,4 ± 7,1%. 48,4% presentaba un VFDVD mayor de 150 ml/m2 y el 32,8% mayor a 170 ml/ m2. El PTA se relacionó con mayores volúmenes de VD que la AInf. VFDVD mayor a 170 ml/m2 mostraron peor FEVD (FEVD 47,9 ± 7% vs 43,2 ± 6,4%, p < 0,01). DISCUSIÓN: Casi la mitad mostró una significativa dilatación del VD demostrando que la indicación de RMC es tardía en el seguimiento. El PTA se asoció con mayores VFDVD y VFSVD pero no a peor FEVD.


INTRODUCCIÓN: Tetralogy of Fallot (TOF) is the most frequent cyanotic congenital heart disease. Pulmonary regurgitation (PR) and right ventricle (RV) enlargement and dysfunction are the most common long-term complications. Cardiac magnetic resonance (CMR) is the gold standard for RV evaluation. OBJECTIVE: To analyze CMR results in the follow-up of TOF patients. PATIENTS AND METHOD: All CMR performed between 2007 and 2012 in TOF patients with transannular patch (TAP) repair or infundibular widening, and without pulmonary valve replacement (PVR) were included. Pulmonary regurgitant fraction (PRF), ventricular end-diastolic (EDV) and end-systolic volume (ESV), and ejection fraction (EF) were examined. RESULTS: 122 CMR were performed in 114 patients. Average age at CMR was 15.4±7.4 years. 53.3% of them presented severe PR (> 40%). RVEDV was 157.3 ± 38.6 ml/m2, RVESV was 85.3 ± 27 ml/m2 and RVEF was 46.4 ± 7.1%. RVEDV was > 150 ml/ m2 in 48.4% and > 170 ml/m2 in 32.8% of patients. Patients with TAP showed larger RV volumes compared with those with infundibular widening. RVEDV > 170 ml/m2 showed worse RVEF that those with lower RVEDV (47.9 ± 7% vs 43.2 ± 6.4%, p < 0.01). CONCLUSION: Almost half of the pa tients showed significant RV enlargement, demonstrating that the indication of CMR is late in their follow-up. TAP was associated with higher RVEDV and RVESV, but no worse RVEF.


Asunto(s)
Humanos , Masculino , Femenino , Lactante , Preescolar , Niño , Adolescente , Complicaciones Posoperatorias/diagnóstico por imagen , Tetralogía de Fallot/cirugía , Imagen por Resonancia Magnética , Hipertrofia Ventricular Derecha/diagnóstico por imagen , Disfunción Ventricular Derecha/diagnóstico por imagen , Tetralogía de Fallot/diagnóstico por imagen , Estudios Retrospectivos , Estudios de Seguimiento , Hipertrofia Ventricular Derecha/etiología , Disfunción Ventricular Derecha/etiología
13.
Mol Psychiatry ; 23(6): 1402-1409, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-28584286

RESUMEN

We conducted a genome-wide meta-analysis of cognitive empathy using the 'Reading the Mind in the Eyes' Test (Eyes Test) in 88,056 research volunteers of European Ancestry (44,574 females and 43,482 males) from 23andMe Inc., and an additional 1497 research volunteers of European Ancestry (891 females and 606 males) from the Brisbane Longitudinal Twin Study. We confirmed a female advantage on the Eyes Test (Cohen's d=0.21, P<2.2 × 10-16), and identified a locus in 3p26.1 that is associated with scores on the Eyes Test in females (rs7641347, Pmeta=1.58 × 10-8). Common single nucleotide polymorphisms explained 5.8% (95% CI: 4.5%-7.2%; P=1.00 × 10-17) of the total trait variance in both sexes, and we identified a twin heritability of 28% (95% CI: 13%-42%). Finally, we identified significant genetic correlation between the Eyes Test and anorexia nervosa, openness (NEO-Five Factor Inventory), and different measures of educational attainment and cognitive aptitude.


Asunto(s)
Empatía/genética , Empatía/fisiología , Adulto , Anciano , Anorexia Nerviosa/genética , Cognición/fisiología , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Trastornos Mentales/genética , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Factores Sexuales , Gemelos , Población Blanca/genética
14.
Diabetes Metab Res Rev ; 33(6)2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28371189

RESUMEN

BACKGROUND: The aim of the study was to investigate the different B-cell responses after a glucagon stimulation test (GST) versus mixed meal tolerance test (MMTT). METHODS: We conducted GST and MMTT in 10 healthy people (aged 25-40 years) and measured C-peptide, gastric inhibitory peptide (GIP) and glucagon-like peptide-1 (GLP-1) at different time points after the administration of 1 mg i.v. glucagon for GST or a liquid mixed meal for MMTT. RESULTS: The GST stimulated C-peptide showed a mean increase of 147.1%, whereas the mean increase of MMTT stimulated C-peptide was 99.82% (Δincrease = 47.2%). Maximum C-peptide level reached with the MMTT was greater than that obtained with the GST (C-pept max MMTT = 2.35 nmol/L vs C-pep max GST = 1.9 nmol/L). A positive and linear correlation was found between the GST incremental area under the curve C-peptide and the MMTT incremental area under the curve C-peptide (r = 0.618, P = .05). After GST, there was no increment of GIP and glucagon like peptide-1 levels compared to baseline levels. A positive and linear correlation between GIP and C-peptide levels was observed only for the MMTT (r = 0.922, P = .008) indicating that in the GST, the C-peptide response is independent of the incretin axis response. CONCLUSIONS: Although the 2 stimulation tests may elicit a similar response in C-peptide secretion, B-cell response to MMTT depends on a functionally normal incretin axis. These results may have implications when investigating the B-cell response in people with diabetes and for studies in which stimulated C-peptide secretion is used as primary or secondary outcome for response to therapy.


Asunto(s)
Péptido C/metabolismo , Diabetes Mellitus Tipo 2/diagnóstico , Técnicas de Diagnóstico Endocrino , Polipéptido Inhibidor Gástrico/farmacología , Péptido 1 Similar al Glucagón/farmacología , Glucagón/administración & dosificación , Células Secretoras de Insulina/efectos de los fármacos , Comidas , Adulto , Estudios Cruzados , Diabetes Mellitus Tipo 2/fisiopatología , Ingestión de Alimentos/fisiología , Femenino , Humanos , Células Secretoras de Insulina/fisiología , Masculino , Estimulación Química
15.
Phys Chem Chem Phys ; 19(4): 3366-3383, 2017 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-28092379

RESUMEN

We report a comprehensive theoretical study of the structural and electronic properties of neutral and charged nickel oxide clusters, NinOm0/± (n = 3-8 and m = 1-10), in the context of recent experiments of photodissociation and Ion Mobility Mass Spectrometry. By means of density functional theory calculations in the generalized gradient approximation for exchange and correlation, we determined the putative ground states as well as the low-energy structural- and spin-isomers which were then used to explore the favorable fragmentation channels of the nickel oxide cationic clusters, and the resulting most abundant products, in good qualitative agreement with photodissociation measurements. Apart from stoichiometries different from those of their nickel oxide macroscopic counterparts, we found a tendency to form compact Ni subclusters, with reentrance of low-coordinated structures close to the equiatomic Ni-O concentration, taking the form of alternating Ni-O rings in the smaller sizes, in good qualitative agreement with Ion Mobility Mass Spectrometry measurements. This structural pattern is manifested in a drop of the total spin magnetic moment close to the equiatomic concentration due to the formation of antiparallel magnetic couplings. Although antiparallel couplings are found to a more or less extent in most clusters, especially in the oxygen rich phase, we identified certain clusters of special interest in the context of magnetic grains because of their large total magnetic moment and abundance. There are even some nickel oxide clusters with a higher total moment than their pure Ni counterparts, due to parallel magnetic couplings and the contribution of the oxygen atoms to the total moment.

16.
Int J Cardiol ; 228: 870-880, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-27889554

RESUMEN

Idiopathic dilated cardiomyopathy has become one of the most prevalent inherited cardiomyopathies over the past decades. Genetic screening of first-degree relatives has revealed that 30-50% of the cases have a familial origin. Similar to other heart diseases, familial dilated cardiomyopathy is characterized by a high genetic heterogeneity that complicates family studies. Cli'nical screening, 12-lead electrocardiogram and transthoracic echocardiogram are recommended for patients and first-degree family members. Magnetic resonance also needs to be considered. Genetic technologies have become fundamental for the clinical management of this disease. New generation sequencing methods have made genetic testing feasible for extensive panels of genes related to the disease. Recently, new imaging modalities such as speckle-tracking, strain and strain rate or magnetic resonance, and circulating biomarkers such as non-coding RNAs, have emerged as potential strategies to help cardiologists in their clinical practice. Imaging, genetic and blood-based techniques should be considered together in the evaluation and testing of familial dilated cardiomyopathy. Here, we discuss the current procedures and novel approaches for the clinical management of familial dilated cardiomyopathy.


Asunto(s)
Cardiomiopatía Dilatada/diagnóstico , Biomarcadores/sangre , Cardiomiopatía Dilatada/sangre , Cardiomiopatía Dilatada/genética , Diagnóstico por Imagen , Pruebas Genéticas , Humanos
17.
Sci Rep ; 6: 37354, 2016 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-27874027

RESUMEN

Contractile dysfunction is underdiagnosed in early stages of diabetic cardiomyopathy. We evaluated the potential of circulating long non-coding RNAs (lncRNAs) as biomarkers of subclinical cardiac abnormalities in type 2 diabetes. Forty-eight men with well-controlled type 2 diabetes and 12 healthy age-matched volunteers were enrolled in the study. Left ventricular (LV) parameters were measured by magnetic resonance imaging. A panel of lncRNAs was quantified in serum by RT-qPCR. No differences in expression levels of lncRNAs were observed between type 2 diabetes patients and healthy volunteers. In patients with type 2 diabetes, long intergenic non-coding RNA predicting cardiac remodeling (LIPCAR) was inversely associated with diastolic function, measured as E/A peak flow (P < 0.050 for all linear models). LIPCAR was positively associated with grade I diastolic dysfunction (P < 0.050 for all logistic models). Myocardial infarction-associated transcript (MIAT) and smooth muscle and endothelial cell-enriched migration/differentiation-associated long noncoding RNA (SENCR) were directly associated with LV mass to LV end-diastolic volume ratio, a marker of cardiac remodelling (P < 0.050 for all linear models). These findings were validated in a sample of 30 patients with well-controlled type 2 diabetes. LncRNAs are independent predictors of diastolic function and remodelling in patients with type 2 diabetes.


Asunto(s)
Biomarcadores/sangre , Diabetes Mellitus Tipo 2/sangre , ARN Largo no Codificante/sangre , Función Ventricular Izquierda , Remodelación Ventricular , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/fisiopatología , Corazón/diagnóstico por imagen , Corazón/fisiopatología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , ARN Largo no Codificante/genética
18.
Nutr Diabetes ; 6(8): e222, 2016 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-27525817

RESUMEN

BACKGROUND: In the MADIAB trial (a 21-day randomized, controlled trial in patients with type 2 diabetes (T2D)), intervention with the Ma-Pi 2 macrobiotic diet resulted in significantly greater improvements in metabolic control compared with a standard recommended diet for patients with T2D. We report on a 6-month follow-up study, which investigated, whether these benefits extended beyond the 21-day intensive dietary intervention, in real-world conditions. SUBJECTS: At the end of the MADIAB trial (baseline of this follow-up study), all participants continued their assigned diet (Ma-Pi or control) for 6 months. The Ma-Pi 2 group followed the Ma-Pi 4 diet during this follow-up study. Forty of the original 51 subjects (78.4%) participated in the follow-up (body mass index, 27-45 kg m(-2); age, 40-75 years). Primary outcome was percentage change from baseline in HbA1c; secondary outcomes were anthropometric data and lipid panel. RESULTS: A significantly greater median percentage reduction was observed for HbA1c in the Ma-Pi group (-11.27% (95% confidence interval (CI): -10.17; -12.36)) compared with the control group (-5.88% (95% CI: -3.79; -7.98)) (P < 0.001). Total and low-density lipoprotein (LDL) cholesterol increased in both groups with no differences between groups (P=0.331 and P=0.082, respectively). After correcting for age and gender, the Ma-Pi diet was associated with a higher percentage reduction in HbA1c (95% CI: 2.56; 7.61) and body weight (95% CI: 0.40; 3.99), and a higher percentage increase in LDL cholesterol (95% CI: -1.52; -33.16). However, all participants' total and LDL cholesterol levels remained within recommended ranges (<200 mg dl(-1) and <100 mg dl(-1), respectively). The Ma-Pi diet group achieved the target median HbA1c value (<5.7% (39 mmol mol(-1))) at 6 months. CONCLUSIONS: Both the Ma-Pi and control diets maintained their benefits beyond the 21-day intensive monitored intervention over a 6-month follow-up in real-world conditions. The Ma-Pi diet resulted in greater improvement in glycemic control.


Asunto(s)
Diabetes Mellitus Tipo 2/dietoterapia , Dieta Macrobiótica , Adulto , Anciano , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Estudios de Seguimiento , Hemoglobina Glucada/metabolismo , Humanos , Lípidos/sangre , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
19.
Antimicrob Agents Chemother ; 60(2): 717-28, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26525784

RESUMEN

Class C ß-lactamases poorly hydrolyze cephamycins (e.g., cefoxitin, cefotetan, and moxalactam). In the past 2 decades, a new family of plasmid-based AmpC ß-lactamases conferring resistance to cefoxitin, the FOX family, has grown to include nine unique members descended from the Aeromonas caviae chromosomal AmpC. To understand the basis for the unique cephamycinase activity in the FOX family, we determined the first X-ray crystal structures of FOX-4, apo enzyme and the acyl-enzyme with its namesake compound, cefoxitin, using the Y150F deacylation-deficient variant. Notably, recombinant expression of N-terminally tagged FOX-4 also yielded an inactive adenylylated enzyme form not previously observed in ß-lactamases. The posttranslational modification (PTM), which occurs on the active site Ser64, would not seem to provide a selective advantage, yet might present an opportunity for the design of novel antibacterial drugs. Substantial ligand-induced changes in the enzyme are seen in the acyl-enzyme complex, particularly the R2 loop and helix H10 (P289 to N297), with movement of F293 by 10.3 Å. Taken together, this study provides the first picture of this highly proficient class C cephamycinase, uncovers a novel PTM, and suggests a possible cephamycin resistance mechanism involving repositioning of the substrate due to the presence of S153P, N289P, and N346I substitutions in the ligand binding pocket.


Asunto(s)
Antibacterianos/farmacología , Proteínas Bacterianas/ultraestructura , Cefoxitina/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Proteínas de Escherichia coli/ultraestructura , beta-Lactamasas/ultraestructura , Aeromonas caviae/efectos de los fármacos , Secuencia de Aminoácidos , Antibacterianos/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Cefoxitina/metabolismo , Cristalografía por Rayos X , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Datos de Secuencia Molecular , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/ultraestructura , Procesamiento Proteico-Postraduccional , Alineación de Secuencia , Espectrometría de Masas en Tándem , beta-Lactamasas/genética , beta-Lactamasas/metabolismo
20.
Mol Psychiatry ; 20(8): 1011-6, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25224261

RESUMEN

Human brain anatomy is strikingly diverse and highly inheritable: genetic factors may explain up to 80% of its variability. Prior studies have tried to detect genetic variants with a large effect on neuroanatomical diversity, but those currently identified account for <5% of the variance. Here, based on our analyses of neuroimaging and whole-genome genotyping data from 1765 subjects, we show that up to 54% of this heritability is captured by large numbers of single-nucleotide polymorphisms of small-effect spread throughout the genome, especially within genes and close regulatory regions. The genetic bases of neuroanatomical diversity appear to be relatively independent of those of body size (height), but shared with those of verbal intelligence scores. The study of this genomic architecture should help us better understand brain evolution and disease.


Asunto(s)
Encéfalo/anatomía & histología , Genoma , Fenotipo , Adolescente , Estudios de Cohortes , Simulación por Computador , Femenino , Estudio de Asociación del Genoma Completo , Técnicas de Genotipaje , Humanos , Imagen por Resonancia Magnética , Masculino , Modelos Genéticos , Tamaño de los Órganos , Polimorfismo de Nucleótido Simple
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