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1.
Nanomaterials (Basel) ; 13(1)2023 Jan 01.
Article in English | MEDLINE | ID: mdl-36616107

ABSTRACT

The fabrication of NiO films by different routes is important to extend and improve their applications as hole-transporting layers in organic and inorganic optoelectronic devices. Here, an automated ultrasonic pyrolysis spray method was used to fabricate NiO and Li-doped NiO thin films using nickel acetylacetonate and lithium acetate dihydrate as metal precursor and dimethylformamide as solvent. The effect of the amount of lithium in the precursor solution on the structural, morphological, optical, and electrical properties were studied. XRD results reveal that all the samples are polycrystalline with cubic structure and crystallite sizes in the range of 21 to 25 nm, without any clear trend with the Li doping level. AFM analysis shows that the crystallites form round-shaped aggregates and all the films have low roughness. The optical transmittance of the films reaches values of 60% to 77% with tendency upward as Li content is increased. The electrical study shows that the films are p-type, with the carrier concentration, resistivity, and carrier mobility depending on the lithium doping. NiO:Li (10%) films were successfully incorporated into inorganic light emitting diodes together with Mn-doped ZnS and ZnO:Al films, all deposited on ITO by the same ultrasonic spray pyrolysis technique.

2.
J Pers Med ; 12(9)2022 Aug 30.
Article in English | MEDLINE | ID: mdl-36143197

ABSTRACT

Device-related thrombus (DRT) after left atrial appendage (LAA) closure is infrequent but correlates with an increased risk of thromboembolism. Therefore, the search for DRT predictors is a topic of interest. In the literature, multivariable methods have been used achieving non-consistent results, and to the best of our knowledge, machine learning techniques have not been used yet for thrombus detection after LAA occlusion. Our aim is to compare both methodologies with respect to predictive power and the search for predictors of DRT. To this end, a multicenter study including 1150 patients who underwent LAA closure was analyzed. Two lines of experiments were performed: with and without resampling. Multivariate and machine learning methodologies were applied to both lines. Predictive power and the extracted predictors for all experiments were gathered. ROC curves of 0.5446 and 0.7974 were obtained for multivariate analysis and machine learning without resampling, respectively. However, the resampling experiment showed no significant difference between them (0.52 vs. 0.53 ROC AUC). A difference between the predictors selected was observed, with the multivariable methodology being more stable. These results question the validity of predictors reported in previous studies and demonstrate their disparity. Furthermore, none of the techniques analyzed is superior to the other for these data.

3.
Molecules ; 26(24)2021 Dec 15.
Article in English | MEDLINE | ID: mdl-34946677

ABSTRACT

Composite scaffolds are commonly used strategies and materials employed to achieve similar analogs of bone tissue. This study aims to fabricate 10% wt polylactic acid (PLA) composite fiber scaffolds by the air-jet spinning technique (AJS) doped with 0.5 or 0.1 g of zirconium oxide nanoparticles (ZrO2) for guide bone tissue engineering. ZrO2 nanoparticles were obtained by the hydrothermal method and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). SEM and fourier-transform infrared spectroscopy (FTIR) analyzed the synthesized PLA/ZrO2 fiber scaffolds. The in vitro biocompatibility and bioactivity of the PLA/ZrO2 were studied using human fetal osteoblast cells. Our results showed that the hydrothermal technique allowed ZrO2 nanoparticles to be obtained. SEM analysis showed that PLA/ZrO2 composite has a fiber diameter of 395 nm, and the FITR spectra confirmed that the scaffolds' chemical characteristics are not affected by the synthesized technique. In vitro studies demonstrated that PLA/ZrO2 scaffolds increased cell adhesion, cellular proliferation, and biomineralization of osteoblasts. In conclusion, the PLA/ZrO2 scaffolds are bioactive, improve osteoblasts behavior, and can be used in tissue bone engineering applications.


Subject(s)
Nanoparticles/chemistry , Osteoblasts/metabolism , Polyesters/chemistry , Tissue Engineering , Tissue Scaffolds/chemistry , Zirconium/chemistry , Calcification, Physiologic , Cell Adhesion , Cell Line , Cell Proliferation , Humans , Osteoblasts/cytology
4.
Rev Esp Cardiol (Engl Ed) ; 74(7): 591-601, 2021 Jul.
Article in English, Spanish | MEDLINE | ID: mdl-32830074

ABSTRACT

INTRODUCTION AND OBJECTIVES: The NitOcclud Lê VSD Coil was specifically designed for transcatheter occlusion of ventricular septal defects (VSD) and became available for this purpose in August 2010. Our objective was to describe the Spanish experience of this technique and analyze its reliability and short- to mid-term efficacy. METHODS: National multicenter observational study, which retrospectively recruited all patients (of any age) with VSD (of any location or type) who underwent percutaneous NitOcclud occlusion, using an intention-to-treat analysis, until January 2019. RESULTS: A total of 117 attempts were made to implant at least 1 NitOcclud in 116 patients in 13 institutions. The median [range] age and weight was 8.6 [0.4-69] years and 27 [5.8-97] kg, respectively. In 99 patients (85%), the VSD was an isolated congenital defect. The location was perimembranous in 95 (81%), and 74 (63%) of them were aneurysmatic. The mean fluoroscopy time was 34 [11.4-124] minutes. Of the 117 attempts, 104 were successful (89%) with a follow-up of 31.4 [0.6-59] months. At the last review, final complete occlusion of the defect without residual shunt or with only a minimal shunt was achieved in 92.3% (no shunt, n=73; trivial shunt, n=23). Four patients required a second procedure for residual shunt occlusion. Two devices had to be surgically explanted due to severe hemolysis. There were no deaths or other major complications. CONCLUSIONS: The NitOcclud device can be used successfully for a wide anatomical spectrum of VSD. The main issue is residual shunt, but its incidence decreases over time. The incidence of hemolysis was very low and no permanent changes were detected in atrioventricular conduction.


Subject(s)
Cardiac Catheterization , Heart Septal Defects, Ventricular , Heart Septal Defects, Ventricular/surgery , Humans , Registries , Reproducibility of Results , Retrospective Studies , Treatment Outcome
5.
J Clin Med ; 9(7)2020 Jul 19.
Article in English | MEDLINE | ID: mdl-32707736

ABSTRACT

INTRODUCTION AND OBJECTIVE: Major bleeding events in patients undergoing left atrial appendage closure (LAAC) range from 2.2 to 10.3 per 100 patient-years in different series. This study aimed to clarify the bleeding predictive factors that could influence these differences. METHODS: LAAC was performed in 598 patients from the Iberian Registry II (1093 patient-years; median, 75.4 years). We conducted a multivariate analysis to identify predictive risk factors for major bleeding events. The occurrence of thromboembolic and bleeding events was compared to rates expected from CHA2DS2-VASc (congestive heart failure, hypertension, age, diabetes, stroke history, vascular disease, sex) and HAS-BLED (hypertension, abnormal renal and liver function, stroke, bleeding, labile INR, elderly, drugs or alcohol) scores. RESULTS: Cox regression analysis revealed that age ≥75 years (HR: 2.5; 95% CI: 1.3 to 4.8; p = 0.004) and a history of gastrointestinal bleeding (GIB) (HR: 2.1; 95% CI: 1.1 to 3.9; p = 0.020) were two factors independently associated with major bleeding during follow-up. Patients aged <75 or ≥75 years had median CHA2DS2-VASc scores of 4 (IQR: 2) and 5 (IQR: 2), respectively (p < 0.001) and HAS-BLED scores were 3 (IQR: 1) and 3 (IQR: 1) for each group (p = 0.007). Events presented as follow-up adjusted rates according to age groups were stroke (1.2% vs. 2.9%; HR: 2.4, p = 0.12) and major bleeding (3.7 vs. 9.0 per 100 patient-years; HR: 2.4, p = 0.002). Expected major bleedings according to HAS-BLED scores were 6.2% vs. 6.6%, respectively. In patients with GIB history, major bleeding events were 6.1% patient-years (HAS-BLED score was 3.8 ± 1.1) compared to 2.7% patients-year in patients with no previous GIB history (HAS-BLED score was 3.4 ± 1.2; p = 0.029). CONCLUSIONS: In this high-risk population, GIB history and age ≥75 years are the main predictors of major bleeding events after LAAC, especially during the first year. Age seems to have a greater influence on major bleeding events than on thromboembolic risk in these patients.

6.
Appl Radiat Isot ; 153: 108815, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31344649

ABSTRACT

In this paper, luminescent properties of Europium trivalent ion in the matrix with unbalanced charge of barium hafnate under UV radiation, with special emphasis on the 5D0 → 7F0 transition are reported. The synthesis was conducted by the hydrothermal route at 200 °C with a reaction time of 90 min using chlorides as raw materials. In order to determinate the luminescent quenching concentration, the samples were doped with different amounts of Europium trivalent ions being the sample doped with 1 and 3% at of Eu3+ which shows the highest luminescent emission. X-ray diffraction analysis showed that the material crystallize in the cubic perovskite structure with space group Pm-3m. The Energy Dispersive Spectroscopy (EDS) shows there are not elements other those that Ba, Hf, O and Eu in the synthesized material. Photoluminescent emission spectra show peaks of emission associated with the 5D0 → 7FJ (J = 0,1,2,3,4) transitions, characteristics of europium ion. The 5D0 → 7F0 transition centered at 580 nm showed an unusual great intensity when it was excited with the wavelength associated with the charge transfer band (272 nm). Finally the decay time was measured in the 5D0 → 7FJ (J = 0,1,2,3,4) transitions using the sample doped with Eu3+ (3% at).

7.
Rev. esp. cardiol. (Ed. impr.) ; 72(6): 449-455, jun. 2019. tab, graf
Article in Spanish | IBECS | ID: ibc-188405

ABSTRACT

Introducción y objetivos: Muchos pacientes con fibrilación auricular no valvular tienen contraindicados los anticoagulantes orales. El objetivo es estimar la incidencia de eventos tromboembólicos y hemorrágicos en pacientes con fibrilación auricular no valvular y cierre de la orejuela izquierda con seguimiento a largo plazo, y determinar los factores asociados con mayor mortalidad a largo plazo. Métodos: Cohorte prospectiva de pacientes reclutados desde 2009 a 2015. Se compararon los eventos tromboembólicos y hemorrágicos con los esperados según las escalas CHA2DS2-VASc y HAS-BLED. Se realizó un análisis multivariable para determinar las variables asociadas con la mortalidad. Resultados: Se reclutó a 598 pacientes (1.093 pacientes-año) con contraindicación de anticoagulantes (mediana de edad, 75,4 años). La tasa de éxito del cierre de la orejuela izquierda fue del 95,8%; 30 pacientes (5%) presentaron complicaciones. Las tasas de eventos (cada 100 pacientes-año) durante el seguimiento (media, 22,9 meses; mediana, 16,1 meses) fueron: muerte, 7,0%; ictus isquémico, 1,6% (frente al 8,5% esperado según CHA2DS2-VASc; p < 0,001); hemorragia intracraneal, 0,8%; hemorragia gastrointestinal, 3,2%, y hemorragia grave, 3,9% (frente al 6,3% esperado por HAS-BLED; p = 0,002). Estos resultados incluso mejoraron en el subgrupo de 176 pacientes con seguimiento > 24 meses (media, 46,6 meses; 683 pacientes-año) para las hemorragias graves, el 2,6% (frente al 6,3% esperado por HAS-BLED; p < 0,033). La edad (HR = 1,1), las hemorragias intracraneales (HR = 6,8) y el ictus (HR = 2,7) se asociaron con mayor mortalidad. Conclusiones: El cierre de la orejuela izquierda redujo significativamente las incidencias de ictus y de eventos hemorrágicos graves y el beneficio se mantuvo. La edad, las hemorragias intracraneales y el ictus se asociaron con mayor mortalidad


Introduction and objectives: Many patients with nonvalvular atrial fibrillation are still left without protection due to a contraindication for anticoagulants. This study aimed to establish the occurrence of stroke and major bleeding events in patients with nonvalvular atrial fibrillation and left atrial appendage closure with long-term follow-up and to explore the factors associated with higher long-term mortality. Methods: Analysis of a multicenter single cohort prospectively recruited from 2009 to 2015. Thromboembolic and bleeding events were compared with those expected from CHA2DS2-VASc and HAS-BLED scores. Multivariate analysis examined variables associated with mortality during follow-up. Results: A total of 598 patients (1093 patient-years) with a contraindication for anticoagulants were recruited (median 75.4 years). The success rate of left atrial appendage closure device implantation was 95.8%. Thirty patients (5%) experienced periprocedural complications. The rate of events (per 100 patient-years) during follow-up (mean 22.9 months; median 16.1 months) was as follows: death 7.0%; ischemic stroke 1.6% (vs 8.5% expected according to CHA2DS2-VASc; P < .001); intracranial hemorrhage 0.8%; gastrointestinal bleeding 3.2%; severe bleeding 3.9% (vs 6.3% expected by HAS-BLED, P = .002). These results were improved in the subgroup of 176 patients with follow-up > 24 months (mean follow-up 46.6 months, 683 patient-years) for severe bleeding 2.6% (vs 6.3% expected by HAS-BLED, P < .033). The factors significantly associated with higher mortality were age (HR, 1.1), intracranial hemorrhage (HR, 6.8), and stroke during follow-up (HR, 2.7). Conclusions: Left atrial appendage closure significantly reduced the incidence of stroke and bleeding events and the benefit was maintained. Intracranial hemorrhage, age and stroke were associated with higher mortality


Subject(s)
Humans , Male , Female , Aged , Atrial Appendage/surgery , Vascular Closure Devices/statistics & numerical data , Heart Septal Defects, Atrial/surgery , Atrial Fibrillation/complications , Long Term Adverse Effects/prevention & control , Diseases Registries/statistics & numerical data , Atrial Fibrillation/drug therapy , Anticoagulants/adverse effects , Prospective Studies , Thromboembolism/epidemiology , Hemorrhage/epidemiology , Stroke/prevention & control , Indicators of Morbidity and Mortality , Contraindications, Drug
8.
J Invasive Cardiol ; 31(8): 212-216, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31088992

ABSTRACT

BACKGROUND: Stroke recurrence despite optimal oral anticoagulation (OAC) might represent a novel indication for left atrial appendage occlusion (LAAO). The heterogeneity of these patients is generally high, as the presence of valvular atrial fibrillation (VAF) is common. The aim of this study was to explore the role of LAAO as an adjunctive therapy to OAC in patients with recurrent stroke despite optimal OAC. METHODS: The study screened consecutive patients who underwent percutaneous LAAO at nine centers between 2009 and 2017. Patients with recurrent stroke despite optimal OAC were selected and those with an absolute or relative contraindication to OAC were not included in the study. RESULTS: Among 837 patients who underwent LAAO between the study period, a total of 22 (2.6%) met the inclusion criteria. There was a high percentage of VAF (38%) and 59% presented more than one cardioembolic event before LAAO. All patients underwent successful implantation of the device and no procedural major adverse events were reported. In all but 3 patients, anticoagulation was continued after LAAO. With a median clinical follow-up of 1.8 years (range, 0.7-2.8 years), only 1 stroke and 1 transient ischemic attack were reported, translating into a significant reduction of cerebrovascular events before and after LAAO (2.0 ± 1.0 events vs 0.1 ± 0.3 events; P<.01). Imaging follow-up revealed only 1 case of device thrombosis. CONCLUSIONS: LAAO as an adjunctive therapy to OAC seems to be feasible and safe in patients with previous cardioembolic events despite optimal OAC. In our series, this strategy was associated with a low rate of cerebrovascular events after LAAO.


Subject(s)
Anticoagulants/administration & dosage , Atrial Appendage/surgery , Atrial Fibrillation/therapy , Septal Occluder Device , Stroke/prevention & control , Administration, Oral , Aged , Atrial Fibrillation/complications , Female , Follow-Up Studies , Humans , Male , Retrospective Studies , Stroke/etiology , Time Factors , Treatment Outcome
9.
Rev Esp Cardiol (Engl Ed) ; 72(6): 449-455, 2019 Jun.
Article in English, Spanish | MEDLINE | ID: mdl-29754808

ABSTRACT

INTRODUCTION AND OBJECTIVES: Many patients with nonvalvular atrial fibrillation are still left without protection due to a contraindication for anticoagulants. This study aimed to establish the occurrence of stroke and major bleeding events in patients with nonvalvular atrial fibrillation and left atrial appendage closure with long-term follow-up and to explore the factors associated with higher long-term mortality. METHODS: Analysis of a multicenter single cohort prospectively recruited from 2009 to 2015. Thromboembolic and bleeding events were compared with those expected from CHA2DS2-VASc and HAS-BLED scores. Multivariate analysis examined variables associated with mortality during follow-up. RESULTS: A total of 598 patients (1093 patient-years) with a contraindication for anticoagulants were recruited (median 75.4 years). The success rate of left atrial appendage closure device implantation was 95.8%. Thirty patients (5%) experienced periprocedural complications. The rate of events (per 100 patient-years) during follow-up (mean 22.9 months; median 16.1 months) was as follows: death 7.0%; ischemic stroke 1.6% (vs 8.5% expected according to CHA2DS2-VASc; P < .001); intracranial hemorrhage 0.8%; gastrointestinal bleeding 3.2%; severe bleeding 3.9% (vs 6.3% expected by HAS-BLED, P = .002). These results were improved in the subgroup of 176 patients with follow-up > 24 months (mean follow-up 46.6 months, 683 patient-years) for severe bleeding 2.6% (vs 6.3% expected by HAS-BLED, P < .033). The factors significantly associated with higher mortality were age (HR, 1.1), intracranial hemorrhage (HR, 6.8), and stroke during follow-up (HR, 2.7). CONCLUSIONS: Left atrial appendage closure significantly reduced the incidence of stroke and bleeding events and the benefit was maintained. Intracranial hemorrhage, age and stroke were associated with higher mortality.


Subject(s)
Atrial Appendage/surgery , Atrial Fibrillation/surgery , Cardiac Surgical Procedures/methods , Registries , Septal Occluder Device , Stroke/prevention & control , Aged , Aged, 80 and over , Atrial Appendage/diagnostic imaging , Atrial Fibrillation/complications , Atrial Fibrillation/diagnosis , Echocardiography, Transesophageal , Female , Follow-Up Studies , Humans , Incidence , Male , Portugal/epidemiology , Prospective Studies , Spain/epidemiology , Stroke/epidemiology , Stroke/etiology , Time Factors , Treatment Outcome
10.
Micromachines (Basel) ; 9(8)2018 Aug 19.
Article in English | MEDLINE | ID: mdl-30424347

ABSTRACT

The spray pyrolysis technique has been extensively used to synthesize materials for a wide variety of applications such as micro and sub-micrometer dimension MOSFET´s for integrated circuits technology, light emitting devices for displays, and solid-state lighting, planar waveguides and other multilayer structure devices for photonics. This technique is an atmospheric pressure chemical synthesis of materials, in which a precursor solution of chemical compounds in the proper solvent is sprayed and converted into powders or films through a pyrolysis process. The most common ways to generate the aerosol for the spraying process are by pneumatic and ultrasonic systems. The synthesis parameters are usually optimized for the materials optical, structural, electric and mechanical characteristics required. There are several reviews of the research efforts in which spray pyrolysis and the processes involved have been described in detail. This review is intended to focus on research work developed with this technique in relation to high-K dielectric and luminescent materials in the form of coatings and powders as well as multiple layered structures.

11.
Appl Radiat Isot ; 92: 91-5, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25016246

ABSTRACT

In this work, the photoluminescent (PL), cathodoluminescent (CL) and thermoluminescent (TL) properties of hafnium oxide films doped with trivalent dysprosium ions are reported. The films were deposited on glass substrates at temperatures ranging from 300 to 600°C, using chlorides as precursor reagents. The surface morphology of films showed a veins shaped microstructure at low deposition temperatures, while at higher temperatures the formation of spherical particles was observed on the surface. X-ray diffraction showed the presence of HfO2 monoclinic phase in the films deposited at temperatures greater than 400°C. The PL and CL spectra of the doped films showed the highest emission band centered at 575nm corresponding to the transitions (4)F9/2→(6)H13/2, which is a characteristic transition of Dy(3+) ion. The greatest emission intensities were observed in samples doped with 1 atomic percent (at%) of DyCl3 in the precursor solution. Regarding the TL behavior, the glow curve of HfO2:Dy(+3) films exhibited spectrum with one broad band centered at about 150°C. The highest intensity TL response was observed on the films deposited at 500°C.

12.
Appl Radiat Isot ; 83 Pt C: 196-9, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23948482

ABSTRACT

Thermo and photoluminescent properties of nanoparticles (NPs) of hafnium oxide (HfO2), both intrinsic and doped with terbium (Tb(3+)) are reported. The NPs of HfO2 were synthesized by hydrothermal route, using hafnium tetrachloride (HfCl4) and terbium chloride hexahydrated (TbCl3∙6H2O) as precursors and sodium hydroxide (NaOH) to adjust the pH. Deionized water was used as solvent in all cases. The synthesis was carried out at different dopant concentrations from 0 to 20 at% of terbium with respect to the amount of hafnium in the precursor solution. The temperature of hydrothermal treatment was 200 °C and 80 min of reaction time. X-ray diffraction results show that at terbium concentrations higher than 15 at% the HfO2 nanoparticles have a crystalline structure corresponding to the tetragonal phase. Thermoluminescent (TL) characterization was performed after 5 min irradiation of the samples with ultraviolet light of 200 nm wavelength. The highest TL emission was observed on samples with 7 at% of Tb, with the TL peak centered at 128 °C. Thermoluminescence analysis shows behavior associated with second-order kinetics with activation energy of 0.49 eV. Photoluminescent spectrum present the characteristics (5)D4→(7)FJ (J=3-6) terbium ion electronic transitions lines centered on 489 nm, 543 nm, 584 nm and 622 nm.

19.
Arch. Hosp. Vargas ; 39(1/2): 69-70, ene.-jun. 1997. ilus
Article in Spanish | LILACS | ID: lil-230618

ABSTRACT

El pneumomediastino o enfisema mediastinal consiste en la presencia de aire en el mediastino. Puede ocurrir complicaciones una variedad de patologías incluyendo el asma bronquial, Presentamos el caso de un paicente asmatico, quien durante una crisis severa desarrolla pneumomediastino. Se revisan los aspectos diagnósticos, implicaciones pronósticas y el tratamiento


Subject(s)
Humans , Male , Female , Asthma/pathology , Mediastinal Emphysema/diagnosis , Mediastinal Emphysema/pathology , Mediastinal Emphysema/therapy
20.
Med. crít. venez ; 2(3): 80-5, jul.-sept. 1987. tab
Article in Spanish | LILACS | ID: lil-63284

ABSTRACT

Se estudian 91 pacientes con criterios diagnósticos de síndrome de dificultad respiratoria del adulto.La mortalidad total grupo fue de 51%. La incidencia de sepsis fue del 69%. La neumonía necrotizante se presentó en 32% y se manifestó con mayor frecuencia en pacientes que permanecieron intubados y sometidos a ventilación mecánica por tiempo prolongado. En este grupo la mortalidad se elevó al 66%. Los gérmenes aislados mas frecuentes fueron seudomona, enterobacter, klebsiella y acinetobacter


Subject(s)
Adult , Humans , Male , Female , Pneumonia/complications , Respiration, Artificial/methods , Respiratory Distress Syndrome, Newborn/diagnosis
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