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1.
Opt Lett ; 48(3): 607, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36723543

RESUMO

We present a corrigendum to our Letter [Opt. Lett.35, 703 (2010)10.1364/OL.35.000703]. In the original Letter we inadvertently included in Fig. 2(a) a TEM micrograph corresponding to a different, but very similar, sample. This corrigendum replaces Fig. 2(a) with a correct version. Since the main results are rather based in optical absorption measurements, and their modeling by using the T-matrix method, this correction does not affect the results and conclusions of the original Letter.

2.
Sci Rep ; 11(1): 16339, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381117

RESUMO

Calpain-2 (CAPN2) is a processing enzyme ubiquitously expressed in mammalian tissues whose pleiotropic functions depend on the role played by its cleaved-products. Nuclear interaction networks, crucial for a number of molecular processes, could be modified by CAPN2 activity. However, CAPN2 functions in cell nucleus are poorly understood. To unveil CAPN2 functions in this compartment, the result of CAPN2-mediated interactions in cell nuclei was studied in breast cancer cell (BCC) lines. CAPN2 abundance was found to be determinant for its nucleolar localization during interphase. Those CAPN2-dependent components of nucleolar proteome, including the actin-severing protein cofilin-1 (CFL1), were identified by proteomic approaches. CAPN2 binding, cleavage and activation of LIM Kinase-1 (LIMK1), followed by CFL1 phosphorylation was studied. Upon CAPN2-depletion, full-length LIMK1 levels increased and CFL1/LIMK1 binding was inhibited. In addition, LIMK1 accumulated at the cell periphery and perinucleolar region and, the mitosis-specific increase of CFL1 phosphorylation and localization was altered, leading to aberrant mitosis and cell multinucleation. These findings uncover a mechanism for the role of CAPN2 during mitosis, unveil the critical role of CAPN2 in the interactions among nuclear components and, identifying LIMK1 as a new CAPN2-target, provide a novel mechanism for LIMK1 activation. CFL1 is crucial for cytoskeleton remodeling and mitosis, but also for the maintenance of nuclear structure, the movement of chromosomes and the modulation of transcription frequently altered in cancer cells. Consequently, the role of CAPN2 in the nuclear compartment might be extended to other actin-associated biological and pathological processes.


Assuntos
Calpaína/metabolismo , Núcleo Celular/metabolismo , Quinases Lim/metabolismo , Actinas/metabolismo , Linhagem Celular Tumoral , Cromossomos/metabolismo , Cofilina 1/metabolismo , Citoesqueleto/metabolismo , Humanos , Células MCF-7 , Mitose/fisiologia , Fosforilação/fisiologia , Ligação Proteica/fisiologia , Proteoma/metabolismo , Proteômica/métodos , Transcrição Gênica/fisiologia
3.
Nanotechnology ; 31(35): 355705, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32422622

RESUMO

Ferromagnetic-like behavior at room temperature (300 K) was observed in Pt particles embedded in ion-implanted silica matrices. Results in samples integrated by ultra-small photoluminescent Pt clusters (<2 nm) were compared with samples containing exclusively larger plasmonic Pt nanoparticles (>3 nm). The ferromagnetic behavior coexists simultaneously with a diamagnetic response. Enhanced diamagnetic response of one order of magnitude was observed compared to typical diamagnetism in pure silica, and it is increased with the mean diameter of the Pt particles. Besides, a larger sensitivity to an external field was observed in the ferromagnetic response of the nanostructures with a characteristic saturation at 20 kOe. This ferromagnetic behavior was only observed in the samples with nucleated Pt particles. The magnitude of the saturation magnetization shows up to a fivefold increase in the samples with smaller particle size and larger particle density. Saturation magnetization was observed between 3-15 × 10-4 emu g-1, with remanent magnetization of 0.2-0.6 × 10-4emu g-1, measured at 300 K. Coercitive fields also decrease in samples with smaller size and particles density, with values of 114 and 300 Oe. At lower temperatures (5 K) the saturation magnetization increases, as it would be expected from a ferromagnetic state. Optomagnetic response was studied by inverse Faraday effects and induced photomagnetization with circular polarized picosecond pulsed light at 1064 nm wavelength. Results showed that samples with a stronger ferromagnetic response exhibit larger Faraday rotation up to 5.3 × 103deg cm-1 by light excitations with irradiances between 50 and 180 GW cm-2. These findings have immediate applications in multifunctional solid-state magneto-optical devices such as optical isolators, high-data storage devices and ultrafast all-optical switching of magnetization.

5.
J Phys Condens Matter ; 30(27): 274005, 2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29799435

RESUMO

Surface pattern formation on amorphous SiO2 substrates by implantation of 1.0 MeV Si+ ions at a current of 1.3 µA at 70° angle is reported. Surface micrometer sized ripples perpendicular to the ion beam direction are formed, observed by scanning electron microscopy and atomic force microscopy. The morphological features are more or less similar for different fluences. The formation of surface ripples at this energy is discussed in terms of ion stopping mechanisms and patterns obtained within the low- and medium-energy ranges.

6.
J Phys Condens Matter ; 30(13): 135604, 2018 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-29460843

RESUMO

A change in the Kondo lattice behavior of bulk YbAl3 has been observed when the alloy is shaped into nanoparticles (≈12 nm). Measurements of the electrical resistivity show inhibited coherence effects and deviation from the standard Fermi liquid behavior (T 2-dependence). These results are interpreted as being due to the effect of the disruption of the periodicity of the array of Kondo ions provoked by the size reduction process. Additionally, the ensemble of randomly placed nanoparticles also triggers an extra source of electronic scattering at very low temperatures (≈15 K) due to quantum interference effects.

7.
Actas dermo-sifiliogr. (Ed. impr.) ; 108(7): 650-656, sept. 2017. ilus, tab, graf
Artigo em Espanhol | IBECS | ID: ibc-166921

RESUMO

Introducción: Las decisiones terapéuticas en el paciente con psoriasis están influidas por factores de la enfermedad (gravedad, localización, etc.), de las comorbilidades y de otras circunstancias demográficas y clínicas asociadas. Objetivo: Evaluar la fiabilidad de una aplicación móvil, MDi-Psoriasis(R), como instrumento de ayuda al dermatólogo en la toma de decisiones terapéuticas en pacientes con psoriasis moderada-grave. Método: Estudio de concordancia interobservador entre las recomendaciones terapéuticas emitidas por un grupo de expertos y MDi-Psoriasis(R) sobre 10 casos clínicos complejos de psoriasis moderada-grave. Para cada uno de los casos los expertos fueron preguntados por el tratamiento más adecuado, posible y no adecuado. Los mismos 10 casos clínicos fueron sometidos a la aplicación MDi-Psoriasis(R) y se calcularon las concordancias interobservador pareada (kappa de Cohen) y múltiple (kappa de Fleiss), y el porcentaje de acuerdo entre las recomendaciones. Resultados: Sobre un total de 1.210 observaciones el porcentaje promedio de acuerdo fue del 51,3% (IC 95%: 48,5-54,1%), con una concordancia pareada de kappa = 0,29 y múltiple de kappa = 0,28. El acuerdo promedio entre pares de observadores, sin MDi-Psoriasis(R), fue del 50,5% (IC 95%: 47,6-53,5%). La concordancia pareada entre las recomendaciones emitidas por MDi-Psoriasis(R) y la opinión mayoritaria de los expertos fue de kappa = 0,44, con un acuerdo del 68,2%. Conclusiones: MDi-Psoriasis(R) puede emitir recomendaciones comparables a las emitidas por un experto en psoriasis (AU)


Background: Therapeutic decisions in psoriasis are influenced by disease factors (e.g., severity or location), comorbidity, and demographic and clinical features. Objective: We aimed to assess the reliability of a mobile telephone application (MDi-Psoriasis) designed to help the dermatologist make decisions on how to treat patients with moderate to severe psoriasis. Method: We analyzed interobserver agreement between the advice given by an expert panel and the recommendations of the MDi-Psoriasis application in 10 complex cases of moderate to severe psoriasis. The experts were asked their opinion on which treatments were most appropriate, possible, or inappropriate. Data from the same 10 cases were entered into the MDi-Psoriasis application. Agreement was analyzed in 3 ways: paired interobserver concordance (Cohen's κ), multiple interobserver concordance (Fleiss's κ), and percent agreement between recommendations. Results: The mean percent agreement between the total of 1210 observations was 51.3% (95% CI, 48.5-54.1%). Cohen's κ statistic was 0.29 and Fleiss's κ was 0.28. Mean agreement between pairs of human observers only, excluding the MDi-Psoriasis recommendations, was 50.5% (95% CI, 47.6-53.5%). Paired agreement between the recommendations of the MDi-Psoriasis tool and the majority opinion of the expert panel (Cohen's κ) was 0.44 (68.2% agreement). Conclusions: The MDi-Psoriasis tool can generate recommendations that are comparable to those of experts in psoriasis (AU)


Assuntos
Humanos , Psoríase/tratamento farmacológico , Fármacos Dermatológicos/uso terapêutico , Árvores de Decisões , Sistemas de Apoio a Decisões Clínicas , Aplicativos Móveis , Comorbidade , Etanercepte/uso terapêutico , Metotrexato/uso terapêutico
8.
Actas Dermosifiliogr ; 108(7): 650-656, 2017 Sep.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28385425

RESUMO

BACKGROUND: Therapeutic decisions in psoriasis are influenced by disease factors (e.g., severity or location), comorbidity, and demographic and clinical features. OBJECTIVE: We aimed to assess the reliability of a mobile telephone application (MDi-Psoriasis) designed to help the dermatologist make decisions on how to treat patients with moderate to severe psoriasis. METHOD: We analyzed interobserver agreement between the advice given by an expert panel and the recommendations of the MDi-Psoriasis application in 10 complex cases of moderate to severe psoriasis. The experts were asked their opinion on which treatments were most appropriate, possible, or inappropriate. Data from the same 10 cases were entered into the MDi-Psoriasis application. Agreement was analyzed in 3 ways: paired interobserver concordance (Cohen's κ), multiple interobserver concordance (Fleiss's κ), and percent agreement between recommendations. RESULTS: The mean percent agreement between the total of 1210 observations was 51.3% (95% CI, 48.5-54.1%). Cohen's κ statistic was 0.29 and Fleiss's κ was 0.28. Mean agreement between pairs of human observers only, excluding the MDi-Psoriasis recommendations, was 50.5% (95% CI, 47.6-53.5%). Paired agreement between the recommendations of the MDi-Psoriasis tool and the majority opinion of the expert panel (Cohen's κ) was 0.44 (68.2% agreement). CONCLUSIONS: The MDi-Psoriasis tool can generate recommendations that are comparable to those of experts in psoriasis.


Assuntos
Tomada de Decisão Clínica , Fármacos Dermatológicos/uso terapêutico , Dermatologia/métodos , Aplicativos Móveis , Psoríase/tratamento farmacológico , Adulto , Telefone Celular , Contraindicações de Medicamentos , Estudos Transversais , Prova Pericial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Terapia PUVA , Psoríase/radioterapia , Reprodutibilidade dos Testes , Terapia Ultravioleta
10.
J Phys Condens Matter ; 27(49): 496002, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26593408

RESUMO

The structural state and static and dynamic magnetic properties of TbCu2 nanoparticles are reported to be produced by mechanical milling under inert atmosphere. The randomly dispersed nanoparticles as detected by TEM retain the bulk symmetry with an orthorhombic Imma lattice and Tb and Cu in the 4e and 8h positions, respectively. Rietveld refinements confirm that the milling produces a controlled reduction of particle sizes reaching ≃6 nm and an increase of the microstrain up to ≃0.6%. The electrical resistivity indicates a metallic behavior and the presence of a magnetic contribution to the electronic scattering which decreases with milling times. The dc-susceptibility shows a reduction of the Néel transition (from 49 K to 43 K) and a progressive increase of a peak (from 9 K to 15 K) in the zero-field-cooled magnetization with size reduction. The exchange anisotropy is very weak (a bias field of ≃30 Oe) and is due to the presence of a disordered (thin) shell coupled to the antiferromagnetic core. The dynamic susceptibility evidences a critical slowing down in the spin-disordered state for the lowest temperature peak associated with a spin glass-like freezing with a tendency of zv and ß exponents to increase when the size becomes 6 nm (zv ≃ 6.6 and ß ≃ 0.85). A Rietveld analysis of the neutron diffraction patterns 1.8 ≤ T ≤ 60 K, including the magnetic structure determination, reveals that there is a reduction of the expected moment (≃80%), which must be connected to the presence of the disordered particle shell. The core magnetic structure retains the bulk antiferromagnetic arrangement. The overall interpretation is based on a superantiferromagnetic behavior which at low temperatures coexists with a canting of surface moments and a mismatch of the antiferromagnetic sublattices of the nanoparticles. We propose a novel magnetic phase diagram where changes are provoked by a combination of the decrease of size and the increase of microstrain.

13.
Opt Express ; 23(3): 3176-85, 2015 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-25836176

RESUMO

We present the fabrication and characterization of channel waveguides based on composites containing silver nanoparticles. The substrate employed is silica and the nanoparticles were produced by a masked ion-implantation technique. Multiple implantation processes were made at different energies in order to produce waveguides with an appropriate width. We also present results for the characterization of the waveguiding properties of the devices produced.

14.
An Pediatr (Barc) ; 83(4): 229-35, 2015 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-25639163

RESUMO

INTRODUCTION: Strength is a physical quality with a clear influence on quality of life. It is determined by the structure of the musculoskeletal system, and depends on the muscular structure. It has been described that prematurity conditions both qualities. The aims of this study are to determine whether prematurity is associated with strength or body composition and evaluate the relationship between prematurity, strength and muscle mass. MATERIAL AND METHODS: Case-control study. Participants were premature 7-to-11 year-old children and full-term birth controls. Strength was measured by a strength gauge and body composition from DEXA (duel-energy X-ray absorptiometry) scans. A total of 89 subjects were included and divided into three groups: 30 prematures with birth-weight ≤ 1500g, 29 prematures with birth-weight 1500-2000g, and 30 controls. RESULTS: Weight and BMI z-score was lower in the premature group. No differences were found in muscular mass or strength between groups. A ratio was established between strength and weight or muscular mass. It was observed that it was possible for them to move four times their weight, without finding any differences between groups or a relationship with birth-weight. CONCLUSIONS: Between 7 and 11 years of age, children who were premature have lower weight and BMI than the rest of the children. However, there were no differences in body composition or strength between preterm children and controls.


Assuntos
Composição Corporal , Extremidade Inferior/fisiologia , Força Muscular , Estudos de Casos e Controles , Criança , Estudos Transversais , Feminino , Humanos , Recém-Nascido Prematuro , Masculino , Estudos Prospectivos
15.
An Pediatr (Barc) ; 83(5): 297-303, 2015 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-25617975

RESUMO

INTRODUCTION: Parental obesity is a risk factor for childhood obesity. The aim of this study was to determine if parental obesity influences the adherence and success of obesity treatment in a hospital paediatric endocrinology clinic. MATERIAL AND METHODS: An analytical, prospective, longitudinal study was conducted on obese children aged 4-14. An initial body mass index (BMI), and again at 6 months after receiving health, hygiene and dietary recommendations. Success was considered as a decrease of 0.5 in the BMI Z-score, and adherence to attending the 6-month review. Parental BMI was determined to identify overweight. The χ(2) test was used for qualitative variables and the T-Student test for quantitative (significance, p<<.05). RESULTS: The study included 100 children (52 male), 9.9±2.7 years old, BMI 28.1± 4.5kg/m(2) and BMI Z-Score 3.11±0.98. (85% had a BMI Z-score>3). More than half (59%) of the children had one or both parents obese (41 fathers and 37 mothers were obese). Treatment was not adhered to by 25 children. Adherence was worse if both parents were obese OR 3.65 (1.3 to 10.5) (P<=.01) and adherence was better if the mother was not obese, although the father was (P=.01). The treatment had significant success in 40 patients. If the mother was the only obese one in the family, the possibility of treatment failure was greater OR 5.6 (1.4 to 22.4) (P<.01) CONCLUSIONS: A high percentage of children with severe obesity have obese parents. The mother has an important influence on adherence and response to treatment for the severely obese child.


Assuntos
Índice de Massa Corporal , Obesidade/terapia , Pais , Adolescente , Criança , Pré-Escolar , Endocrinologia , Feminino , Hospitais Pediátricos , Humanos , Estudos Longitudinais , Masculino , Estudos Prospectivos
16.
An Pediatr (Barc) ; 82(2): 89-94, 2015 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-24735909

RESUMO

OBJECTIVES: The aim is to study the sleep duration and the 24-hour sleep distribution pattern in children under 2 years-old from two different areas of Spain, as well as to determine the prevalence of abnormal sleep duration and the influence of age on this prevalence, and compare them with the already published data. MATERIAL AND METHODS: An observational, descriptive and cross-sectional study on children from two health centers: one in Castilla y León and the other in Asturias. Their parents completed the Brief Infant Sleep Questionnaire (BISQ). Daytime and nighttime sleep duration was assessed, with percentiles being used to evaluate the results. Two groups were created: one according to the age (children under or above 6 months), and the other according to the area. RESULTS: A total of 125 children were studied (73 males). The nighttime sleep duration increased from 8.28±2.06 hours to 10.43±1.21 hours (P=.0001) and the daytime sleep decreased from 4.61±2.66 to 1.96±0.79 hours (P=.0001) for children under 6 months and above 6 months, respectively. The children from Castilla y León slept more during daytime than those from Asturias (3.91±2.67 vs 3.00±2.09 hours, P=.041). Nineteen children had a total sleep duration below the 2nd percentile. A sleep duration below normal percentiles was observed in children under 6 months (14/72 vs 5/53, P=.006). CONCLUSIONS: As children grow older, they substitute daytime sleep for nighttime sleep. Approximately 15% of the children under 2 years-old may have changes in sleep duration, and is more common in children under 6 months.


Assuntos
Sono , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Sono/fisiologia , Fatores de Tempo
20.
Acta pediatr. esp ; 72(5): e156-e162, mayo 2014. tab
Artigo em Espanhol | IBECS | ID: ibc-122712

RESUMO

Objetivos: Evaluar la prevalencia y las características de los hábitos miccionales e intestinales en la población infantil de nuestro entorno, e identificar las relaciones existentes entre ellos, comparándolos también con los resultados obtenidos en otras poblaciones distintas a la nuestra. Material y métodos: Se diseñó un estudio observacional, descriptivo y transversal sobre hábitos miccionales e intestinales en una muestra de niños de último curso de enseñanza primaria. Después de realizar una encuesta anónima sobre estos hábitos, se incluyó en el estudio a un total de 98 escolares. Para evaluar su relación con los hábitos miccionales e intestinales, se dividieron en grupos en función del sexo y la presencia o no de incontinencia urinaria. Resultados: La tasa de participación fue del 70,40%. Se analizaron las tasas de prevalencia para los síntomas miccionales e intestinales, y se observó que los hábitos miccionales anormales más frecuentes fueron las maniobras de retención en 30 niños (43,3%), la urgencia miccional en 25 (36,2%), la nicturia en 20 (29%), la frecuencia miccional aumentada en 17 (24,6%), el chorro débil en 14 (20,3%), la presencia de algún tipo de incontinencia en 10 (14,4%), el goteo posmiccional en 7 (10,1%), los escapes con la risa o el esfuerzo en 6 (8,7%) y el chorro intermitente en 5 (7,2%). En 4 individuos (5,8%) se observó incontinencia diurna, nicturna o mixta, frecuencia miccional disminuida o retardo al iniciar la micción. Por último, en 2 (2,9%) se advirtió un esfuerzo para mantener la micción, dolor frecuente con la micción o estreñimiento, y sólo en 1 (1,4%) se registró escape de heces. Además, la incontinencia urinaria fue más frecuente en los individuos de sexo femenino. Conclusiones: La encuesta diseñada y validada mediante el presente estudio ha resultado ser una herramienta original y útil para dicho fin, permitiendo detectar y describir problemas de salud a nivel comunitario. El sexo femenino favorece la presencia de incontinencia urinaria en los pacientes pediátricos. En los sujetos con incontinencia urinaria es más probable la presencia de frecuencia miccional aumentada, goteo posmiccional, chorro miccional intermitente y estreñimiento (AU)


Objectives: To asses the prevalence and characteristics of voiding and bowel habits in children in our area, and to identify relationships between them, comparing them with results obtained in other populations disparate from ours. Material and methods: We designed a cross-sectional observational study on voiding and bowel habits in a sample of children in the last year of primary education. After conducting an anonymous survey on these habits, a total of 98 schoolchildren were included in the study. To evaluate its relationship with urinary and bowel habits, groups were created with respect to sex and the presence or absence of urinary incontinence. Results: The response rate was 70.40%. We analyzed the prevalence rates for urinary and bowel symptoms, showing that the most common abnormal voiding habits were holding maneuvers in 30 (43.3%), urgency in 25 (36.2%), nicturia in 20 (29%), increased urinary frequency in 17 (24.6%), weak stream in 14 (20.3%), any type of incontinence in 10 (14.4%), post void dribbling in 7 (10, 1%), escapes with laughter or effort in 6 (8.7%) and intermittent stream in 5 (7.2%). Four individuals (5.8%) had daytime, nocturnal or mixed incontinence, decreased urinary frequency or delay to initiate urination. Finally, in 2 (2.9%) was noted effort to maintain the voiding, pain with urination or constipation, and only in 1 (1.4%) stool leakage. In addition, urinary incontinence was more common in female individuals. Conclusions: The survey designed and validated by this study has proven to be an original and useful tool for this purpose, allowing to detect and describe health problems at community level. Female sex favours the presence of urinary incontinence in children. Urinary incontinence has a positive effect on the occurrence of increased voiding frequency, post void dribbling, intermittent urine stream and. These data deserve to be analyzed in future studies more comprehensively (AU)


Assuntos
Humanos , Masculino , Feminino , Criança , Hábitos , Micção , Incontinência Urinária/epidemiologia , Coleta de Dados/métodos , Constipação Intestinal/epidemiologia , Enurese Noturna/epidemiologia
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