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1.
Nat Mater ; 22(7): 867-872, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37349399

RESUMEN

The emergence of a topological transition of the polaritonic dispersion in twisted bilayers of anisotropic van der Waals materials at a given twist angle-the photonic magic angle-results in the diffractionless propagation of polaritons with deep-subwavelength resolution. This type of propagation, generally referred to as canalization, holds promise for the control of light at the nanoscale. However, the existence of a single photonic magic angle hinders such control since the canalization direction in twisted bilayers is unique and fixed for each incident frequency. Here we overcome this limitation by demonstrating multiple spectrally robust photonic magic angles in reconfigurable twisted α-phase molybdenum trioxide (α-MoO3) trilayers. We show that canalization of polaritons can be programmed at will along any desired in-plane direction in a single device with broad spectral ranges. These findings open the door for nanophotonics applications where on-demand control is crucial, such as thermal management, nanoimaging or entanglement of quantum emitters.


Asunto(s)
Fotones , Anisotropía
2.
Phys Rev Lett ; 130(20): 201901, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37267571

RESUMEN

The LHCb collaboration has recently reported the largest CP violation effect from a single amplitude, as well as other giant CP asymmetries in several B-meson decays into three charmless light mesons. It is also claimed that this is predominantly due to ππ→KK[over ¯] rescattering in the final state, particularly in the 1 to 1.5 GeV region. In these analyses the ππ→KK[over ¯] amplitude is by default estimated from the ππ elastic scattering amplitude and does not describe the existing ππ→KK[over ¯] scattering data. Here we show how the recent model-independent dispersive analysis of ππ→KK[over ¯] data can be easily implemented in the LHCb formalism. This leads to a more accurate description of the asymmetry, while being consistent with the measured scattering amplitude and confirming the prominent role of hadronic final state interactions, paving the way for more elaborated analyses.

3.
Cir Pediatr ; 28(1): 36-39, 2015 Jan 13.
Artículo en Español | MEDLINE | ID: mdl-27775269

RESUMEN

Intussusception in infants and young children is a relatively common entity with a well defined clinical picture and a favorable outcome in most cases.The neonatal intussusceptions is extremely rare and does not have a well-defined clinical picture since its clinical manifestations vary according to the gestational time it occurs, the response of the injured intestine and the gestational age of the child concerned. Two new cases of neonatal intussusceptions are presented and a review of the world literature is performed. Given the stage of intussusceptions (pre- or postnatal) occurs and gestational age of the affected infant (preterm or term), there are three entities with clinical characteristics, topography and evolution rather different: prenatal or intrauterine intussusception, postnatal intussusception in the preterm and postnatal intussusception in the term infant.


La invaginación intestinal en el lactante y niño pequeño es una entidad relativamente frecuente, con un cuadro clínico definido y una evolución favorable en la mayoría de los casos. La invaginación intestinal neonatal es sumamente rara y no tiene un cuadro bien definido, ya que sus manifestaciones clínicas varían de acuerdo con el momento gestacional en que se produce, con la respuesta del intestino lesionado y con la edad gestacional del niño afectado. Se presentan dos nuevos casos de invaginación intestinal neonatal y se realiza una revisión de la bibliografía mundial. Teniendo en cuenta la etapa en que se produce la invaginación (pre o postnatal) y la edad gestacional del neonato afectado (prematuro o a término), se pueden distinguir tres entidades con características clínicas, topográficas y evolutivas bien diferentes: la invaginación intestinal prenatal o intraútero, la invaginación intestinal postnatal en el prematuro y la invaginación intestinal postnatal en el neonato a término.

4.
Actas Dermosifiliogr ; 105(5): 487-96, 2014 Jun.
Artículo en Inglés, Español | MEDLINE | ID: mdl-24630429

RESUMEN

INTRODUCTION AND OBJECTIVES: To analyze the triggers of atopic dermatitis (AD), adherence to medical recommendations, disease control, and health-related quality of life (HRQOL) from the patient's perspective. PATIENTS AND METHODS: This was a multicenter, cross-sectional, epidemiological study with the participation of adults (age >16 years; n=125) and children (age, 2-15 years, n=116). Patients had a history of at least 12 months of moderate to severe AD with a moderate to severe flare (Investigator Global Assessment score>2) at the time of recruitment. The Mann-Whitney U test was used to evaluate relationships between disease severity, determined according to the Scoring in Atopic Dermatitis index, and triggers reported by patients, adherence to recommendations and pharmacological therapy, HRQOL, and patient-perceived control. RESULTS: The most common triggers were cosmetic products, clothing, mites, detergents/soaps, and changes in temperature. In 47.2% of adults and 39.7% of children, pharmacological therapy was not initiated at flare onset. Adherence was highest to pharmacological therapy, skin moisturizing, and medical care recommendations. Disease control was considered insufficient by 41.6% of adults and 27. 6% of pediatric patients and, in adults, this was associated with the severity of AD (P=.014). CONCLUSIONS: The therapeutic control of AD is susceptible to improvement, especially in adults. Although patients state that they follow medical recommendations, a significant percentage of patients do not apply recommended treatments correctly. Better education about the disease and its management would appear to be necessary to improve disease control and HRQOL.


Asunto(s)
Dermatitis Atópica/etiología , Dermatitis Atópica/terapia , Cooperación del Paciente , Calidad de Vida , Adolescente , Adulto , Actitud Frente a la Salud , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Masculino , Índice de Severidad de la Enfermedad , Adulto Joven
5.
Oecologia ; 173(1): 83-93, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23386048

RESUMEN

Animals often announce their unprofitability to predators through conspicuous coloured signals. Here we tested whether the apparently conspicuous colour designs of the four European Coraciiformes and Upupiformes species may have evolved as aposematic signals, or whether instead they imply a cost in terms of predation risk. Because previous studies suggested that these species are unpalatable, we hypothesized that predators could avoid targeting them based on their colours. An experiment was performed where two artificial models of each bird species were exposed simultaneously to raptor predators, one painted so as to resemble the real colour design of these birds, and the other one painted using cryptic colours. Additionally, we used field data on the black kite's diet to compare the selection of these four species to that of other avian prey. Conspicuous models were attacked in equal or higher proportions than their cryptic counterparts, and the attack rate on the four species increased with their respective degree of contrast against natural backgrounds. The analysis of the predator's diet revealed that the two least attacked species were negatively selected in nature despite their abundance. Both conspicuous and cryptic models of one of the studied species (the hoopoe) received fewer attacks than cryptic models of the other three species, suggesting that predators may avoid this species for characteristics other than colour. Globally, our results suggest that the colour of coraciiforms and upupiforms does not function as an aposematic signal that advises predators of their unprofitability, but also that conspicuous colours may increase predation risk in some species, supporting thus the handicap hypothesis.


Asunto(s)
Comunicación Animal , Aves/anatomía & histología , Color , Conducta Predatoria , Rapaces/fisiología , Animales , Señales (Psicología) , Dieta , Factores de Riesgo
6.
Eur J Cancer Care (Engl) ; 22(3): 400-12, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23331323

RESUMEN

We conducted a multicentre, retrospective, observational study including patients with solid tumours (excluding breast cancer) that received granulocyte colony-stimulating factors (G-CSF) and chemotherapy. We investigated the effectiveness of daily vs. non-daily G-CSFs (pegfilgrastim) adjusting by potential confounders. The study included 391 patients (211 daily G-CSF; 180 pegfilgrastim), from whom 47.3% received primary prophylaxis (PP) (57.8% pegfilgrastim), 26.3% secondary prophylaxis (SP: initiation after cycle 1 and no reactive treatment in any cycle) (51.5% pegfilgrastim) and 26.3% reactive treatment (19.4% pegfilgrastim). Only 42.2% of patients with daily G-CSF and 46.2% with pegfilgrastim initiated prophylaxis within 72 h after chemotherapy, and only 10.5% of patients with daily G-CSF received it for ≥ 7 days. In the multivariate models, daily G-CSF was associated with higher risk of grade 3-4 neutropenia (G3-4N) vs. pegfilgrastim [odds ratio (OR): 1.73, 95% confidence interval (CI): 1.004-2.97]. Relative to SP, PP protected against G3-4N (OR for SP vs. PP: 6.0, 95%CI: 3.2-11.4) and febrile neutropenia (OR: 3.1, 95%CI: 1.1-8.8), and was associated to less chemotherapy dose delays and reductions (OR for relative dose intensity <85% for SP vs. PP: 3.1, 95%CI: 1.7-5.4) and higher response rate (OR: 2.1, 95%CI: 1.2-3.7). Data suggest that pegfilgrastim, compared with a daily G-CSF, and PP, compared with SP, could be more effective in preventing neutropenia and its related events in the clinical practice.


Asunto(s)
Antineoplásicos/uso terapéutico , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Neoplasias/tratamiento farmacológico , Neutropenia/prevención & control , Anciano , Quimioterapia Combinada , Femenino , Filgrastim , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Neoplasias/complicaciones , Polietilenglicoles , Proteínas Recombinantes/uso terapéutico , Estudios Retrospectivos
7.
Actas Dermosifiliogr ; 104(5): 409-17, 2013 Jun.
Artículo en Inglés, Español | MEDLINE | ID: mdl-23665434

RESUMEN

OBJECTIVE: To evaluate health-related quality of life (HRQOL), patient satisfaction, and adherence to treatment in patients with moderate or severe atopic dermatitis on maintenance therapy. MATERIAL AND METHODS: We performed a national, multicenter, cross-sectional, epidemiological study in adults and children with moderate or severe atopic dermatitis of at least 16 months' duration who were receiving maintenance therapy. We used the Dermatology Life Quality Index (DLQI), the children's version of this scale (cDLQI), and the Morisky medication adherence scale. Visual analog scales were used to measure treatment satisfaction. We used the Mann-Whitney U test to compare HRQOL between patients with moderate and severe disease and the Wilcoxon test to compare the frequency and duration of flares before and after the start of maintenance therapy. RESULTS: We studied 141 children and 141 adults; the prevalence of moderate AD in these groups was 85.8% and 79.4%, respectively. The impact of AD on HRQOL was mild to moderate. Maintenance therapy led to a significant decrease in the frequency and duration of flares (P < .001). While treatment satisfaction was high in both groups, adherence was poor (18.4%-42.6% in children and 14.9%-27.0% in adults). CONCLUSIONS: Patients with moderate and severe AD receiving maintenance therapy experience a reduction in the number and duration of flares and an improvement in HRQOL. While treatment satisfaction is high, adherence rates could be improved.


Asunto(s)
Dermatitis Atópica/tratamiento farmacológico , Cumplimiento de la Medicación/estadística & datos numéricos , Satisfacción del Paciente , Calidad de Vida , Adulto , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Índice de Severidad de la Enfermedad
9.
Cir Pediatr ; 20(1): 63-7, 2007 Jan.
Artículo en Español | MEDLINE | ID: mdl-17489498

RESUMEN

The splenic cysts are rare among all age groups and there are a few reports in the world literature. The splenic epidermoid cyst is a true congenital one, that can cause signs and symptoms, or suffer complications. For these reasons, some form of treatment is recommended. The management of splenic cysts continues to evolve. The standard treatment was splenectomy, but the knowledge about the immunologic function of the spleen and the existence of postesplenectomy mortal sepsis, have conduced most of pediatric surgeons to adopt techniques that preserves splenic tissue. The treatment by percutaneous drainage with injection of a sclerosing agent has complications and a significant recurrence rate. During the last two decades, preservation procedures such as partial splenectomy or partial cyst excision and omental packing have gained the preference of most pediatric surgeons. The second technique has advantages over the partial splenectomy. The possibility to perform the procedure by a laparoscopic approach add the advantages of this last technique. We present two patients with splenic epidermoid cyst treated by laparoscopic partial cyst decapsulation and review the literature.


Asunto(s)
Quiste Epidérmico/cirugía , Laparoscopía/métodos , Enfermedades del Bazo/cirugía , Adolescente , Niño , Quiste Epidérmico/diagnóstico por imagen , Femenino , Humanos , Radiografía , Enfermedades del Bazo/diagnóstico por imagen
10.
Rev. esp. cardiol. (Ed. impr.) ; 75(4): 325-333, abr. 2022. ilus, tab
Artículo en Español | IBECS (España) | ID: ibc-206726

RESUMEN

Introducción y objetivos: El implante percutáneo de la válvula aórtica se ha consolidado como tratamiento de la estenosis aórtica grave inoperable o de alto riesgo quirúrgico. Recientemente las indicaciones se han ampliado a riesgo intermedio y bajo. Nuestro objetivo es evaluar la eficiencia de SAPIEN 3 frente al tratamiento médico conservador (TMC) o el reemplazo quirúrgico de válvula aórtica (RVA) en pacientes sintomáticos inoperables con riesgo alto e intermedio.´Métodos: Análisis de coste-efectividad de SAPIEN 3 frente a RVA/TMC mediante un modelo de Markov (ciclos mensuales) adaptado con 8 estados definidos por la New York Hearth Association y resultados a 15 años, incluidos las complicaciones mayores y el tratamiento tras el alta hospitalaria, desde la perspectiva del Sistema Nacional de Salud. Los parámetros de efectividad se basan en los estudios PARTNER. Se incluyeron costes sanitarios (en euros de 2019) derivados del procedimiento, hospitalización, complicaciones clínicas y seguimiento. Se aplicó una tasa de descuento anual del 3% en costes y beneficios. El análisis de sensibilidad fue determinístico y probabilístico (Monte Carlo). Resultados: En comparación con el RVA (riesgo alto e intermedio) y el TMC (inoperables), el SAPIEN 3 implicó mejores resultados en las 3 poblaciones y menor estancia. Las tasas de coste-utilidad incremental fueron 5.471 (riesgo alto), 8.119 (riesgo intermedio) y 9.948 (inoperables) euros/años de vida ajustados por calidad ganados. En el análisis probabilístico, el SAPIEN 3 resultó coste-efectivo por encima del 75% de las simulaciones en los 3 perfiles. Conclusiones: En nuestro medio, el SAPIEN 3 permite un tratamiento eficiente de la estenosis aórtica grave tanto en pacientes inoperables como en riesgo alto e intermedio (AU)


Introduction and objectives: Transcatheter aortic valve implant has become a widely accepted treatment for inoperable patients with aortic stenosis and patients at high surgical risk. Its indications have recently been expanded to include patients at intermediate and low surgical risk. Our aim was to evaluate the efficiency of SAPIEN 3 vs conservative medical treatment (CMT) or surgical aortic valve replacement (SAVR) in symptomatic inoperable patients at high or intermediate risk. Methods: We conducted a cost-effectiveness analysis of SAPIEN 3 vs SAVR/CMT, using a Markov model (monthly cycles) with 8 states defined by the New York Heart Association and a time horizon of 15 years, including major complications and management after hospital discharge, from the perspective of the National Health System. Effectiveness parameters were based on the PARTNER trials. Costs related to the procedure, hospitalization, complications, and follow-up were included (euros in 2019). An annual discount rate of 3% was applied to both costs and benefits. Deterministic and probabilistic sensitivity analyses (Monte Carlo) were performed. Results: Compared with SAVR (high and intermediate risk) and CMT (inoperable), SAPIEN 3 showed better clinical results in the 3 populations and lower hospital stay. Incremental cost-utility ratios (€/quality-adjusted life years gained) were 5471 (high risk), 8119 (intermediate risk) and 9948 (inoperable), respectively. In the probabilistic analysis, SAPIEN 3 was cost-effective in more than 75% of the simulations in the 3 profiles. Conclusions: In our health system, SAPIEN 3 facilitates efficient management of severe aortic stenosis in inoperable and high- and intermediate-risk patients (AU)


Asunto(s)
Humanos , Reemplazo de la Válvula Aórtica Transcatéter/economía , Estenosis de la Válvula Aórtica/cirugía , Índice de Severidad de la Enfermedad , Análisis Costo-Beneficio , Cadenas de Markov
11.
Evolution ; 60(4): 856-68, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16739465

RESUMEN

Patterns of selection are widely believed to differ geographically, causing adaptation to local environmental conditions. However, few studies have investigated patterns of phenotypic selection across large spatial scales. We quantified the intensity of selection on morphology in a monogamous passerine bird, the barn swallow Hirundo rustica, using 6495 adults from 22 populations distributed across Europe and North Africa. According to the classical Darwin-Fisher mechanism of sexual selection in monogamous species, two important components of fitness due to sexual selection are the advantages that the most attractive males acquire by starting to breed early and their high annual fecundity. We estimated directional selection differentials on tail length (a secondary sexual character) and directional selection gradients after controlling for correlated selection on wing length and tarsus length with respect to these two fitness components. Phenotype and fitness components differed significantly among populations for which estimates were available for more than a single year. Likewise, selection differentials and selection gradients differed significantly among populations for tail length, but not for the other two characters. Sexual selection differentials differed significantly from zero across populations for tail length, particularly in males. Controlling statistically for the effects of age reduced the intensity of selection by 60 to 81%, although corrected and uncorrected estimates were strongly positively correlated. Selection differentials and gradients for tail length were positively correlated between the sexes among populations for selection acting on breeding date, but not for fecundity selection. The intensity of selection with respect to breeding date and fecundity were significantly correlated for tail length across populations. Sexual size dimorphism in tail length was significantly correlated with selection differentials with respect to breeding date for tail length in male barn swallows across populations. These findings suggest that patterns of sexual selection are consistent across large geographical scales, but also that they vary among populations. In addition, geographical patterns of phenotypic selection predict current patterns of phenotypic variation among populations, suggesting that consistent patterns of selection have been present for considerable amounts of time.


Asunto(s)
Passeriformes/genética , Passeriformes/fisiología , Factores de Edad , Migración Animal , Animales , Ambiente , Europa (Continente) , Evolución Molecular , Femenino , Geografía , Masculino , Fenotipo , Caracteres Sexuales , Conducta Sexual Animal
12.
Rev. mex. ing. bioméd ; 41(1): 43-56, ene.-abr. 2020. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1139323

RESUMEN

Abstract In this paper, we present a novel approach to training classifiers in a speller based on P300 potentials. The method, based on bootstrapping, is a known strategy for generating new samples, but it is rarely used in neurosciences. The study first demonstrates how the performance of the classification task (detecting P300 and Non-P300 classes) could be sub-optimal in the traditional approach. Then, a new method for taking new samples from the training data is proposed. Each classifier is re-trained using balanced sub-groups of individual P300 and non-P300 samples. Data were collected from 14 healthy subjects, using 16 electroencephalography channels. These were filtered in bandpass and decimated. Subsequently, four linear classifiers were trained using the traditional method followed by the proposed one, with 1000, 2000 and 3000 samples per class. Results indicate an improvement in the accuracy and discrimination capacity of discriminative classifiers with the proposed method, maintaining the same statistical properties between the training and test data. By contrast, for generative classifiers, there is no significant difference in the results. Therefore, the proposed method is highly recommended for training discriminative classifiers in spell-based P300 potentials.


Resumen Este artículo presenta un método novedoso para entrenar clasificadores en un deletreador basado en potenciales P300. El método, basado en bootstrapping, es una estrategia conocida para generar nuevas muestras pero escasamente implementado en neurociencias. El estudio muestra cómo el rendimiento de la detección de P300 (frente a No-P300) puede resultar sub-óptimo usando el método tradicional. Luego, se propone un nuevo método donde se toman nuevas muestras a partir de los datos de entrenamiento. Con ellas, se re-entrena al clasificador usando sub-grupos equilibrados de muestras individuales P300 y No-P300. Los datos se recolectaron de 14 sujetos sanos, usando 16 canales de electroencefalografía. Estos fueron filtrados en pasa-banda y diezmados. Posteriormente, cuatro clasificadores lineales fueron entrenados, usando primero el método tradicional y después el método propuesto, con 1000, 2000 y 3000 muestras por clase. Los resultados muestran una mejoría en la precisión y la capacidad de discriminación de clasificadores discriminativos con el método propuesto, manteniendo las mismas propiedades estadísticas entre los datos de entrenamiento y los de prueba. En contraste, para los clasificadores generativos, no existe una diferencia significativa en los resultados. Por consiguiente, el método propuesto es altamente recomendado para entrenar clasificadores discriminativos en deletreadores basados en potenciales P300.

13.
BMC Evol Biol ; 3: 6, 2003 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-12702218

RESUMEN

BACKGROUND: An important component of sexual selection arises because females obtain viability benefits for their offspring from their mate choice. Females choosing extra-pair fertilization generally favor males with exaggerated secondary sexual characters, and extra-pair paternity increases the variance in male reproductive success. Furthermore, females are assumed to benefit from 'good genes' from extra-pair sires. How additive genetic variance in such viability genes is maintained despite strong directional selection remains an evolutionary enigma. We propose that sexual selection is associated with elevated mutation rates, changing the balance between mutation and selection, thereby increasing variance in fitness and hence the benefits to be obtained from good genes sexual selection. Two hypotheses may account for such elevated mutation: (1) Increased sperm production associated with sperm competition may increase mutation rate. (2) Mutator alleles increase mutation rates that are revealed by the expression of condition-dependent secondary sexual characters used by choosy females during their mate choice. M Petrie has independently developed the idea that mutator alleles may account for the maintenance of genetic variation in viability despite strong directional selection. RESULTS: A comparative study of birds revealed a positive correlation between mutation rate at minisatellite loci and extra-pair paternity, but not between mutation rate and relative testes mass which is a measure of relative sperm production. Minisatellite mutation rates were not related to longevity, suggesting a meiotic rather than a mitotic origin of mutations. CONCLUSION: We found evidence of increased mutation rate in species with more intense sexual selection. Increased mutation was not associated with increased sperm production, and we suggest that species with intense sexual selection may maintain elevated mutation rates because sexual selection continuously benefits viability alleles expressed in condition-dependent characters. Sexual selection may increase mutational input, which in turn feeds back on sexual selection because of increased variance in viability traits.


Asunto(s)
Mutación de Línea Germinal , Mutagénesis , Selección Genética , Conducta Sexual Animal/fisiología , Espermatozoides/fisiología , Animales , Evolución Molecular , Masculino , Modelos Biológicos , Modelos Genéticos , Caracoles/genética , Espermatozoides/metabolismo
14.
J Immunol Methods ; 227(1-2): 121-35, 1999 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-10485260

RESUMEN

Upon treatment with protein therapeutics, a subset of patients will typically develop antibodies against the drug. These anti-drug antibodies can be of concern because they have the potential to alter the drug's therapeutic activity. In the case of relapsing-remitting multiple sclerosis (RRMS) patients receiving recombinant interferon-beta (IFN-beta), those receiving BETASERON (IFN-beta-1b; E. coli expressed, non-glycosylated, des-Met-1, Cys17Ser recombinant IFN-beta) have a higher incidence of IFN-beta specific antibodies compared to those receiving AVONEX (IFN-beta-1a; mammalian cell-expressed, natural sequence, glycosylated recombinant IFN-beta). The current study reports the development and characterization of ELISAs that detect distinct components of the anti-IFN-beta response in patients' sera, and therefore can potentially be used to characterize the composition of the anti-IFN-beta antibody response. ELISAs were developed using a constant detecting reagent but a variety of IFN-beta-derived test antigens (e.g., native IFN-beta, biotinylated IFN-beta, IFN-beta peptides) and capture methods. Assays were characterized using serum samples from a small number of patients treated with recombinant IFN-beta (either BETASERON or AVONEX). Assays in which IFN-beta was captured via a specific mAb, or in which biotinylated IFN-beta was captured via streptavidin, detected serum antibodies that recognize IFN-beta in its native structural state. In contrast, assays in which IFN-beta was coated directly onto the assay plates detected antibodies that recognize forms of IFN-beta possessing a folded structure distinct from the native structure. Certain epitopes present on native IFN-beta were not represented in these assays in which the test antigen was directly coated on plastic. Antibodies specific for linear epitopes could be detected using linear peptides as test antigens; the locations of these epitopes were mapped by reference to the X-ray crystal structure of IFN-beta-1a. Together, these data show that the mode of antigen presentation employed in IFN-beta ELISAs determines which antibody specificities are detected, and can affect whether or not a given serum sample is identified as positive for anti-IFN-beta antibodies. As a consequence, screening samples in a single ELISA format presenting IFN-beta in a non-native form may lead to underestimation of the incidence of IFN-beta treated MS patients that have generated antibodies specific to the native, active form of the drug.


Asunto(s)
Anticuerpos/sangre , Interferón beta/inmunología , Esclerosis Múltiple/terapia , Reacciones Cruzadas , Ensayo de Inmunoadsorción Enzimática , Epítopos , Humanos , Interferón beta-1a , Interferon beta-1b , Interferón beta/uso terapéutico , Esclerosis Múltiple/inmunología , Proteínas Recombinantes/inmunología
15.
Biotechniques ; 13(3): 412-21, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1382470

RESUMEN

The systematic preparation of synthetic peptide combinatorial libraries (SPCLs), each composed of tens of millions of peptides that can be screened in existing diagnostically or pharmacologically relevant in vitro assay systems, is reviewed. The identification of optimal peptide sequences has been achieved through the screening in solution of SPCLs, each element of which is composed of more than 100,000 nonsupport-bound peptides in equimolar representation, along with an iterative synthesis and screening process. Examples are presented in which an SPCL, composed in total of 52,128,400 acetylated hexa-peptides, is used along with an iterative selection process to precisely identify the antigenic determinant of a peptide recognized by a monoclonal antibody using competitive enzyme-linked immunosorbent assay. This same library was also used to develop highly potent antimicrobial peptides in bacterial growth inhibition assays. A separate non-acetylated SPCL was used to screen and identify high affinity peptide ligands using an opiate radio-receptor binding assay.


Asunto(s)
Evaluación Preclínica de Medicamentos/métodos , Fragmentos de Péptidos/síntesis química , Secuencia de Aminoácidos , Animales , Bioensayo , Encefalina Ala(2)-MeFe(4)-Gli(5) , Encefalinas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Epítopos/inmunología , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Fragmentos de Péptidos/inmunología , Fragmentos de Péptidos/farmacología , Ensayo de Unión Radioligante , Ratas , Receptores de Superficie Celular/metabolismo
16.
Rev Esp Cardiol ; 47(6): 407-9, 1994 Jun.
Artículo en Español | MEDLINE | ID: mdl-8066313

RESUMEN

We report two patients with DDD and VVI pacemakers respectively, in whom telemetry revealed a markedly high bipolar ventricular lead impedance, suggestive of a fracture or other defect in bipolar lead. Pulse generator was able to switch automatically to unipolar pacing, and a loss of ventricular capture was prevented.


Asunto(s)
Marcapaso Artificial/efectos adversos , Anciano , Electrocardiografía , Falla de Equipo , Femenino , Humanos
17.
Rev Esp Cardiol ; 51(1): 27-34, 1998 Jan.
Artículo en Español | MEDLINE | ID: mdl-9580165

RESUMEN

BACKGROUND: Although many variables are useful predictors of post-infarction mortality, their predictive positive values are weak when applied individually. The aim of this study was to determine the prognostic value of the combination of left ventricular ejection fraction, ventricular late potentials and baroreflex sensitivity. PATIENTS AND METHODS: We studied 69 consecutive post-infarction patients. On the day of their discharge from the coronary unit, all patients underwent a two-dimensional echocardiography, to determine the ejection fraction as well as a high resolution electrocardiogram to detect late potentials. To a subset of 49 patients was carried out to learn their baroreflex sensitivity. The patients were followed for 14 +/- 7 months and the following cardiac end points were considered: sudden cardiac death, non sudden cardiac death and non-fatal episodes of sustained ventricular tachycardia or ventricular fibrillation. RESULTS: There were 8 end points: 3 sudden cardiac deaths, 3 non sudden cardiac deaths and 2 successfully resuscitated sustained ventricular tachycardia episodes. The rate of fibrinolysis was 55%. An ejection fraction < 45%, the presence of late potentials and a baroreflex sensitivity < 3.0 msec/mmHg were univariate predictors with predictive positive values of 33%, 24% and 16%, respectively. When ejection fraction < 45%, late potentials and baroreflex sensitivity < 3.0 were combined, we found a significant increase in the positive predictive value (50%). CONCLUSION: The combined determination of ejection fraction, ventricular late potentials and baroreflex sensitivity allows us to identify subset postinfarction patients with a high rate of cardiac complications.


Asunto(s)
Barorreflejo/fisiología , Ecocardiografía , Electrocardiografía , Infarto del Miocardio/diagnóstico , Volumen Sistólico , Anciano , Interpretación Estadística de Datos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/fisiopatología , Valor Predictivo de las Pruebas , Factores de Tiempo
18.
Cities ; 15(4): 245-56, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12294858

RESUMEN

"This paper looks into the set of factors that [influence] the urbanization of the Philippines, a fast-growing developing economy in South East Asia. The paper demonstrates that the ¿migration primacy urbanization model' is an appropriate one that is able to explain the urbanization case in the Philippines. The model draws supporting evidence from rank-size distribution analysis of major cities in the Philippines, a detailed examination of historical, geopolitical and economic forces which have evolved in the development of the Philippines as a sovereign state, and the applicability of the Todaro model on rural-urban migration to the Philippines."


Asunto(s)
Economía , Modelos Teóricos , Dinámica Poblacional , Población Urbana , Urbanización , Asia , Asia Sudoriental , Demografía , Países en Desarrollo , Emigración e Inmigración , Geografía , Filipinas , Población , Investigación
19.
An Otorrinolaringol Ibero Am ; 21(2): 147-57, 1994.
Artículo en Español | MEDLINE | ID: mdl-8209967

RESUMEN

At present the utilization of quantitative techniques in anatomopathological studies is becoming more and more frequent, so adding the possibility of gaining measures and numerical assessments in front of conventional quantitative evaluations. In the paper the AA. report their first attempt with conventional slides of epidermoid carcinomas of the larynx, taken from the files. The aim has been to check out the contribution of this procedure compared with other traditional pathological techniques.


Asunto(s)
Carcinoma de Células Escamosas/patología , Densitometría/métodos , Diagnóstico por Imagen/normas , Neoplasias Laríngeas/patología , Laringe/patología , Carcinoma de Células Escamosas/ultraestructura , Recuento de Células , Movimiento Celular , Densitometría/estadística & datos numéricos , Hematoxilina , Humanos , Neoplasias Laríngeas/ultraestructura , Laringe/ultraestructura , Reproducibilidad de los Resultados
20.
Acta Otorrinolaringol Esp ; 42(5): 337-40, 1991.
Artículo en Español | MEDLINE | ID: mdl-1816793

RESUMEN

At the moment the use of quantitative techniques in anatomopathology are becoming more and more frequent. In this study, with the mathematical transformation of morphometric data obtained from cell populations of epidermoid carcinoma of the larynx, the authors arrive at the "grade of malignancy" for every patient which has in itself prognostic value without taking into account the other anatomopathologic or clinical parameters.


Asunto(s)
Carcinoma de Células Escamosas/patología , Citofotometría , Neoplasias Laríngeas/patología , Aneuploidia , Carcinoma de Células Escamosas/mortalidad , Diferenciación Celular , Núcleo Celular/ultraestructura , ADN de Neoplasias/análisis , Humanos , Neoplasias Laríngeas/mortalidad , Pronóstico , Estudios Retrospectivos
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