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1.
Eur Ann Allergy Clin Immunol ; 52(4): 160-164, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31789491

RESUMEN

Summary: Cut-off values for both skin prick tests (SPT) and specific IgE (sIgE) levels for predicting cow´s milk allergy (CMA) diagnosis are not universally defined. This study is a retrospective analysis of consecutive children (0-18 years-old) with suspected CMA tested with SPT and sIgE for cow's milk (CM) and its fractions between 2016-2017. CMA diagnosis was defined by a positive oral food challenge or a highly suggestive clinical history of CMA and SPT and/or sIgE positive to CM and/or its fractions. One hundred and five patients were included, 58% males with a median age of 2.5 (P25-P75:1-6) years and the diagnosis was confirmed in 83 patients (79%). The variables associated with CMA diagnosis were SPT with CM (p minor 0,05) and casein (p minor 0,05) and all sIgE to CM and its fractions (alfa Lactalbumin, beta Lactoglobulin and casein; p minor 0,05 for all). Optimal cut39 off points (Youden's index) for CMA diagnosis were, for the mean wheal diameter, to CM milk of 4.5mm and to casein of 3mm. For sIgE levels the optimal cut-off points were: for CM of 4.36 kUA/L, alfa-lactalbumin of 1.6 kUA/L, beta-lactoglobulin of 1.7 kUA/L and for casein of 2.6 kUA/L. The role of SPT and sIgE levels to cow´s mlik and its fractions is unequivocal in CMA follow-up. Moreover, sIgE levels seem to be more discriminatory than SPT.


Asunto(s)
Inmunoglobulina E/sangre , Hipersensibilidad a la Leche/diagnóstico , Alérgenos/inmunología , Animales , Bovinos , Niño , Preescolar , Homólogo de la Proteína Chromobox 5 , Femenino , Humanos , Lactante , Masculino , Leche/inmunología , Valor Predictivo de las Pruebas , Pronóstico , Pruebas Cutáneas
3.
Nanotechnology ; 24(27): 275101, 2013 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-23759860

RESUMEN

Bridging the gap between nanoparticulate delivery systems and translational gene therapy is a long sought after requirement in nanomedicine-based applications. However, recent developments regarding nanoparticle functionalization have brought forward the ability to synthesize materials with biofunctional moieties that mimic the evolved features of viral particles. Herein we report the versatile conjugation of both cell penetrating arginine and pH-responsive histidine moieties into the chitosan polymeric backbone, to improve the physicochemical characteristics of the native material. Amino acid coupling was confirmed by 2D TOCSY NMR and Fourier transform infrared spectroscopy. The synthesized chitosan-histidine-arginine (CH-H-R) polymer complexed plasmid DNA biopharmaceuticals, and spontaneously assembled into stable 105 nm nanoparticles with spherical morphology and positive surface charge. The functionalized delivery systems were efficiently internalized into the intracellular compartment, and exhibited remarkably higher transfection efficiency than unmodified chitosan without causing any cytotoxic effect. Additional findings regarding intracellular trafficking events reveal their preferential escape from degradative lysosomal pathways and nuclear localization. Overall, this assembly of nanocarriers with bioinspired moieties provides the foundations for the design of efficient and customizable materials for cancer gene therapy.


Asunto(s)
Arginina/análogos & derivados , Quitosano/análogos & derivados , ADN/administración & dosificación , Histidina/análogos & derivados , Nanopartículas/química , Transfección , ADN/genética , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Nanopartículas/ultraestructura , Plásmidos/administración & dosificación , Plásmidos/genética
4.
Phys Rev Lett ; 108(20): 201302, 2012 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-23003137

RESUMEN

We report the final results of the Phase II SIMPLE measurements, comprising two run stages of 15 superheated droplet detectors each, with the second stage including an improved neutron shielding. The analyses include a refined signal analysis, and revised nucleation efficiency based on a reanalysis of previously reported monochromatic neutron irradiations. The combined results yield a contour minimum of σp=5.7×10(-3) pb at 35 GeV/c2 in the spin-dependent sector of weakly interacting massive particle (WIMP) proton interactions, the most restrictive to date for MW}≤60 GeV/c2 from a direct search experiment and overlapping, for the first time, with results previously obtained only indirectly. In the spin-independent sector, a minimum of 4.7×10(-6) pb at 35 GeV/c2 is achieved, with the exclusion contour challenging a significant part of the light mass WIMP region of current interest.

5.
Phys Rev Lett ; 105(21): 211301, 2010 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-21231283

RESUMEN

We report results of a 14.1 kg d measurement with 15 superheated droplet detectors of total active mass 0.208 kg, comprising the first stage of a 30 kg d Phase II experiment. In combination with the results of the neutron-spin sensitive XENON10 experiment, these results yield a limit of |a(p)|<0.32 for M(W)=50 GeV/c² on the spin-dependent sector of weakly interacting massive particle-nucleus interactions with a 50% reduction in the previously allowed region of the phase space, formerly defined by XENON, KIMS, and PICASSO. In the spin-independent sector, a limit of 2.3×10⁻5 pb at M(W)=45 GeV/c² is obtained.

6.
Animal ; 14(S2): s257-s266, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32638679

RESUMEN

Feeding cattle with on-pasture supplementation or feedlot diets can increase animal efficiency and system profitability while minimizing environmental impacts. However, cattle system profit margins are relatively small and nutrient supply accounts for most of the costs. This paper introduces a nonlinear profit-maximizing diet formulation problem for beef cattle based on well-established predictive equations. Nonlinearity in predictive equations for nutrient requirements poses methodological challenges in the application of optimization techniques. In contrast to other widely used diet formulation methods, we develop a mathematical model that guarantees an exact solution for maximum profit diet formulations. Our method can efficiently solve an often-impractical nonlinear problem by solving a finite number of linear problems, that is, linear time complexity is achieved through parametric linear programming. Results show the impacts of choosing different objective functions (minimizing cost, maximizing profit and maximizing profit per daily weight gain) and how this may lead to different optimal solutions. In targeting improved ration formulation on feedlot systems, this paper demonstrates how profitability and nutritional constraints can be met as an important part of a sustainable intensification production strategy.


Asunto(s)
Algoritmos , Enfermedades de los Bovinos , Dieta , Alimentación Animal , Animales , Bovinos , Dieta/veterinaria , Ambiente , Necesidades Nutricionales , Aumento de Peso
7.
Radiat Prot Dosimetry ; 180(1-4): 230-234, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-29149344

RESUMEN

Superheated droplet detectors (SDDs) are traditionally employed in the detection of neutrons. In this work the focus is on the detection of alpha particles using C2ClF5 as the target liquid. The alpha-droplet interaction is examined via computational studies, and a geometric model developed to describe the expected detector response. Experiments with alpha-emitting uranium- and samarium-doped SDDs at temperatures of 5-12°C confirm that the event rate is related to the size of the droplets, and are in model agreement for temperatures below 8°C; above this temperature, the acoustic sensitivity is reduced by signal attenuation as a result of the increasing bubble population, for which the addition of an attenuation coefficient restores the agreement with experiment. The results suggest the viability of a SDD-based alpha spectrometer using mono-sized droplets.


Asunto(s)
Partículas alfa , Neutrones , Dosis de Radiación , Radiometría/instrumentación , Acústica , Diseño de Equipo , Iones , Tamaño de la Partícula , Presión , Reproducibilidad de los Resultados , Samario/química , Sensibilidad y Especificidad , Espectrofotometría , Temperatura , Uranio/química
9.
Radiat Prot Dosimetry ; 120(1-4): 349-53, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16702246

RESUMEN

This work presents an extensive study on Monte Carlo radiation transport simulation and thermoluminescent (TL) dosimetry for characterising mixed radiation fields (neutrons and photons) occurring in nuclear reactors. The feasibility of these methods is investigated for radiation fields at various locations of the Portuguese Research Reactor (RPI). The performance of the approaches developed in this work is compared with dosimetric techniques already existing at RPI. The Monte Carlo MCNP-4C code was used for a detailed modelling of the reactor core, the fast neutron beam and the thermal column of RPI. Simulations using these models allow to reproduce the energy and spatial distributions of the neutron field very well (agreement better than 80%). In the case of the photon field, the agreement improves with decreasing intensity of the component related to fission and activation products. (7)LiF:Mg,Ti, (7)LiF:Mg,Cu,P and Al(2)O(3):Mg,Y TL detectors (TLDs) with low neutron sensitivity are able to determine photon dose and dose profiles with high spatial resolution. On the other hand, (nat)LiF:Mg,Ti TLDs with increased neutron sensitivity show a remarkable loss of sensitivity and a high supralinearity in high-intensity fields hampering their application at nuclear reactors.


Asunto(s)
Algoritmos , Método de Montecarlo , Reactores Nucleares , Investigación , Dosimetría Termoluminiscente/métodos , Simulación por Computador , Modelos Estadísticos , Portugal , Dosis de Radiación
10.
Radiat Prot Dosimetry ; 120(1-4): 358-60, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16644959

RESUMEN

Al(2)O(3):Mg,Y thermoluminescence (TL) dosemeters were used to measure photon and fast neutron doses in a fast neutron beam recently implemented at the Portuguese Research Reactor, Nuclear and Technological Institute, Portugal. The activation of Al(2)O(3):Mg,Y by fast neutrons provides information about the fast neutron component by measuring the activity of the reaction products and the self-induced TL signal. Additionally, the first TL reading after irradiation determines the photon dose. The elemental composition of the dosemeters was determined by instrumental neutron activation analysis and by particle induced X-ray emission. Results demonstrate that Al(2)O(3):Mg,Y is an adequate material to discriminate photon and fast neutron fields for reactor dosimetry purposes.


Asunto(s)
Óxido de Aluminio/química , Óxido de Aluminio/efectos de la radiación , Neutrones , Fotones , Dosimetría Termoluminiscente/instrumentación , Dosimetría Termoluminiscente/métodos , Relación Dosis-Respuesta en la Radiación , Diseño de Equipo , Análisis de Falla de Equipo , Ensayo de Materiales , Dosis de Radiación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
11.
Radiat Prot Dosimetry ; 120(1-4): 503-8, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16644935

RESUMEN

We describe the fabrication and characterisation of the SIMPLE superheated droplet detector, a 10 g active mass device of C(2)ClF(5) in 1-3% weight concentrations currently employed in a direct search for spin-dependent astroparticle dark matter candidates.


Asunto(s)
Clorofluorocarburos de Metano/química , Clorofluorocarburos de Metano/efectos de la radiación , Radiación Cósmica , Medio Ambiente Extraterrestre , Dosimetría Termoluminiscente/instrumentación , Relación Dosis-Respuesta en la Radiación , Diseño de Equipo , Análisis de Falla de Equipo , Calor , Microburbujas , Dosis de Radiación , Dosimetría Termoluminiscente/métodos
12.
Radiat Prot Dosimetry ; 115(1-4): 398-402, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16381754

RESUMEN

SIMPLE is a superheated droplet detector (SDD) experiment designed to search for the evidence of spin-dependent weakly interacting neutralino dark matter (WIMPs). SDDs, a type of emulsion detector, consist of a uniform suspension of superheated liquid droplets in a compliant material such as a polymeric or aqueous gel. We report on the first neutron spectrometry experiments with SIMPLE SDDs, a spin-off of the neutron detector calibrations performed at the Portuguese Research Reactor. SIMPLE SDDs differ from most SDDs available commercially as they have a 10 times higher loading factor, containing 10(3) times more freon than their commercial counterparts and a 100 times larger volume. We have analysed the response of SIMPLE SDDs to two quasi-monochromatic neutron beams of energies 54 and 144 keV obtained with passive filters. Results show that the characteristic peaks in the fluence distribution of both filters could be determined and their energy position obtained using a simple thermodynamic relation.


Asunto(s)
Neutrones , Protección Radiológica/instrumentación , Radiometría/instrumentación , Análisis Espectral/instrumentación , Transductores , Diseño de Equipo , Análisis de Falla de Equipo , Calor , Dosis de Radiación , Protección Radiológica/métodos , Radiometría/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Soluciones , Análisis Espectral/métodos , Marcadores de Spin
13.
Int J Pediatr Otorhinolaryngol ; 79(8): 1370-3, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26060148

RESUMEN

We present a case report of a four-year-old boy with torcicollis and trismus after acute otitis media. Grisel Syndrome diagnosis in association with temporo-mandibular reactive arthritis was admitted, leading to early conservative treatment. GS should be suspected in a child presenting with torticollis after an upper respiratory tract infection or an ENT surgical procedure. The association with temporo-mandibular reactive findings is somehow rarer but not impossible, due to the close vascular communication between retropharyngeal and pterigoid spaces.


Asunto(s)
Artritis Reactiva/diagnóstico , Articulación Atlantoaxoidea , Luxaciones Articulares/diagnóstico , Otitis Media/diagnóstico , Articulación Temporomandibular , Tortícolis/diagnóstico , Trismo/diagnóstico , Enfermedad Aguda , Preescolar , Humanos , Masculino , Síndrome
14.
Appl Radiat Isot ; 99: 186-92, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25796059

RESUMEN

The radiation field at the epithermal beamline and irradiation chamber installed at the Portuguese Research Reactor (RPI) at the Campus Tecnológico e Nuclear of Instituto Superior Técnico was characterised in the context of Prompt Gamma Neutron Activation Analysis (PGNAA) applications. Radiographic films, activation foils and thermoluminescence dosimeters were used to measure the neutron fluence and photon dose rates in the irradiation chamber. A fixed-source MCNPX model of the beamline and chamber was developed and compared to measurements in the first step towards planning a new irradiation chamber. The high photon background from the reactor results in the saturation of the detector and the current facility configuration yields an intrinsic insensitivity to various elements of interest for PGNAA. These will be addressed in future developments.

15.
Eur Psychiatry ; 30(2): 284-90, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25456156

RESUMEN

BACKGROUND: Interactions between the pharmaceutical industry (PI) and psychiatrists have been under scrutiny recently, though there is little empirical evidence on the nature of the relationship and its intensity at psychiatry trainee level. We therefore studied the level of PI interactions and the underlying beliefs and attitudes in a large sample of European psychiatric trainees. METHODS: One thousand four hundred and forty-four psychiatric trainees in 20 European countries were assessed cross-sectionally, with a 62-item questionnaire. RESULTS: The total number of PI interactions in the preceding two months varied between countries, with least interactions in The Netherlands (M (Mean)=0.92, SD=1.44, range=0-12) and most in Portugal (M=19.06, SD=17.44, range=0-100). Trainees were more likely to believe that PI interactions have no impact on their own prescribing behaviour than that of other physicians (M=3.30, SD=1.26 vs. M=2.39, SD=1.06 on a 5-point Likert scale: 1 "completely disagree" to 5 "completely agree"). Assigning an educational role to the pharmaceutical industry was associated with more interactions and higher gift value (IRR (incidence rate ratio)=1.21, 95%CI=1.12-1.30 and OR=1.18, 95%CI=1.02-1.37). CONCLUSIONS: There are frequent interactions between European psychiatric trainees and the PI, with significant variation between countries. We identified several factors affecting this interaction, including attribution of an educational role to the PI. Creating alternative educational opportunities and specific training dedicated to PI interactions may therefore help to reduce the impact of the PI on psychiatric training.


Asunto(s)
Industria Farmacéutica , Educación de Postgrado en Medicina , Relaciones Interprofesionales , Médicos/estadística & datos numéricos , Pautas de la Práctica en Medicina , Psiquiatría/educación , Adulto , Actitud del Personal de Salud , Estudios Transversales , Europa (Continente) , Femenino , Humanos , Masculino , Encuestas y Cuestionarios
16.
Radiat Prot Dosimetry ; 111(1): 35-9, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15367765

RESUMEN

The characteristics of thermoluminescence dosemeters (TLDs) regarding the determination of photon and neutron absorbed doses were investigated in a thermal neutron beam. Harshaw TLD-100 (LiF:Mg,Ti) and TLD-700 (7LiF:Mg,Ti) were compared with similar materials from Solid Dosimetric Detector and Method Laboratory (People's Republic of China). Harshaw TLD-700H (7LiF:Mg,Cu,P) and aluminium oxide (Al2O3:Mg,Y) from Hungary were also considered for photon dose measurement. The neutron sensitivity of the investigated materials was measured and found to be consistent with values reported by other authors. A comparison was made between the TL dose measurements and results obtained via conventional methods. An agreement within 20% was obtained, which demonstrates the ability of TLD for measuring neutron and photon doses in a mixed field, using careful calibration procedures and determining the neutron sensitivity for the usage conditions.


Asunto(s)
Neutrones , Dosimetría Termoluminiscente , Óxido de Aluminio/efectos de la radiación , Simulación por Computador , Cobre/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Fluoruros/efectos de la radiación , Calor , Compuestos de Litio/efectos de la radiación , Magnesio/efectos de la radiación , Modelos Teóricos , Método de Montecarlo , Reactores Nucleares , Fósforo/efectos de la radiación , Fotones , Sensibilidad y Especificidad , Dosimetría Termoluminiscente/instrumentación , Titanio/efectos de la radiación , Itrio/efectos de la radiación
17.
Acta Med Port ; 14(3): 285-91, 2001.
Artículo en Portugués | MEDLINE | ID: mdl-11552326

RESUMEN

Transient neutropenia in otherwise healthy children is not unusual, the main causes being infections and drugs. The risk of developing an infectious complication in previously healthy children with transient neutropenia is low. These infections are usually superficial and caused by common bacteria. We present two cases of previously healthy children with Pseudomonas sepsis who presented with severe neutropenia, not submitted to recent hospitalization or invasive therapeutic or monitoring proceedings. We discuss the etiology of transitory neutropenia and the reasons for this severe community-acquired infection, caused by an unusual agent. The authors also mention their therapeutic attitudes for previously healthy children with transient neutropenia. They should be guided by clinical presentation and neutropenia severity.


Asunto(s)
Neutropenia/microbiología , Infecciones por Pseudomonas/complicaciones , Sepsis/complicaciones , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Factores de Tiempo
18.
Acta Reumatol Port ; 39(1): 38-45, 2014.
Artículo en Portugués | MEDLINE | ID: mdl-24811460

RESUMEN

AIM: To report and describe a series of four cases of chronic recurrent multifocal osteomyelitis (CRMO) and to discuss therapeutic options, particularly bisphosphonate therapy. METHODS: Retrospective review of four CRMO cases in two Pediatric Units in Lisbon, between 2005 and 2010. RESULTS: Median age of first CRMO symptoms was 11.3 years (range 9-13). The more affected sites were the metaphysis of the long bones, pelvis and coxofemoral joints. Median number of initial bony lesions for each patient was 2.3 (range 1-3) at onset and 3.8 (range 2-6) during the disease course. All patients failed to respond to NSAIDs therapy. Two patients received corticosteroids, with clinical disease remission in only one of them. All patients received bisphosphonates (alendronate in two and pamidronate in two), all with good clinical response and induction of clinical remission in two of them. After a median follow-up period of 4.3 years (range 4-5), three patients are clinically asymptomatic and one patient remains with chronic residual pain. CONCLUSIONS: The treatment of CRMO is not standardized. Bisphosphonate therapy can be of benefit to patients with relapsing symptoms. Randomized controlled multicentric trials are needed to provide better evidence for universal recommendation and definition of bisphosphonate therapy protocol.


Asunto(s)
Difosfonatos/uso terapéutico , Osteomielitis/tratamiento farmacológico , Adolescente , Femenino , Humanos , Masculino , Estudios Retrospectivos
19.
Appl Radiat Isot ; 69(8): 1128-30, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21071234

RESUMEN

The fast neutron irradiation facility of the Portuguese Research Reactor was characterized after the reduction in uranium enrichment and rearrangement of the core configuration. In this work we report on the determination of the hardness parameter and the 1MeV equivalent neutron flux along the facility, in the new irradiation conditions, following ASTM E722 standard.


Asunto(s)
Neutrones Rápidos , Pruebas de Dureza/instrumentación , Método de Montecarlo , Neutrones , Reactores Nucleares/instrumentación , Simulación por Computador , Dosis de Radiación , Monitoreo de Radiación , Radiometría/instrumentación , Investigación
20.
Clin Rheumatol ; 27(12): 1587-91, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18795392

RESUMEN

We report the isolation of Borrelia lusitaniae from a 13-year-old female child presenting with a vasculitis syndrome. The patient was treated with doxycycline, 100 mg bid for 20 days, and is in remission after a follow-up of 2 years. These results should alert clinicians to the fact that B. lusitaniae may be pathogenic in humans, highlighting that patients may be seronegative or present with minimal positive antibody titres and clinical signs that are not specific for Lyme borreliosis. In order to prevent the occurrence of more serious disease manifestations via timely treatment, the analysis by molecular methods may be a useful approach when antibody titres are uninformative.


Asunto(s)
Borrelia/aislamiento & purificación , Enfermedad de Lyme/complicaciones , Enfermedad de Lyme/diagnóstico , Vasculitis/microbiología , Adolescente , Antibacterianos/uso terapéutico , Borrelia/genética , Borrelia/inmunología , Doxiciclina/uso terapéutico , Femenino , Genotipo , Humanos , Inmunoglobulina G , Inmunoglobulina M , Enfermedad de Lyme/tratamiento farmacológico , Datos de Secuencia Molecular , Portugal , Vasculitis/tratamiento farmacológico
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