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1.
Nat Commun ; 12(1): 6999, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34853323

RESUMEN

The evolution of dense plasmas prior to the arrival of the peak of the laser irradiation is critical to understanding relativistic laser plasma interactions. The spectral properties of a reflected laser pulse after the interaction with a plasma can be used to gain insights about the interaction itself, whereas the effect of holeboring has a predominant role. Here we developed an analytical model, describing the non-relativistic temporal evolution of the holeboring velocity in the presence of an arbitrary overdense plasma density and laser intensity profile. We verify this using two-dimensional particle-in-cell simulations, showing a major influence on the holeboring dynamic depending on the density profile. The influence on the reflected laser pulse has been verified during an experiment at the PHELIX laser. We show that this enables the possibility to determine the sub-micrometer scale length of the preplasma by measuring the maximum holeboring velocity and acceleration during the laser-plasma interaction.

2.
Allergy ; 71(6): 901-6, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27012463

RESUMEN

An association between prenatal acetaminophen or ibuprofen intake and an increased risk of asthma and increased IgE level in children is discussed in various epidemiological studies. Although the molecular mechanistic link is still unknown, the question whether or not acetaminophen and/or ibuprofen are safe pain medications during pregnancy arose. In this study, we associate maternal acetaminophen and ibuprofen intake during pregnancy and breastfeeding to infantile asthma phenotypes and elevated IgE level. Therefore, we analysed questionnaires from a local mother-child cohort and monitored drug intake by LC-MS biomonitoring in urine. No association was found between drug intake and any analysed health outcome using questionnaire data. For the information obtained from biomonitoring, no association was found for ibuprofen and acetaminophen intakes during breastfeeding. However, an association between prenatal acetaminophen intake and increased infantile IgEs related to aeroallergens was statistically detected, but not for asthma phenotypes.


Asunto(s)
Alérgenos/inmunología , Analgésicos/efectos adversos , Asma/epidemiología , Asma/etiología , Inmunoglobulina E/inmunología , Exposición Materna/efectos adversos , Animales , Femenino , Humanos , Inmunoglobulina E/sangre , Masculino , Oportunidad Relativa , Embarazo , Estaciones del Año , Factores de Tiempo
3.
J Aerosol Med ; 15(3): 297-303, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12396417

RESUMEN

The efficiency of two different dry powder inhaler systems for the application of the beta2-sympathomimetic drug Formoterol in the lungs has been tested in vitro. Particle size distributions for each device have been measured at four different flow rates (28.3, 40, 60, and 80 L/min) using an Andersen-Impactor. Mass median aerodynamic diameters (MMAD) of the dispersed powder and deposition of the drug in the respiratory tract was determined using a semiempirical lung deposition model. The optimum output for both devices determined by in vitro measurements is supposed to be achieved with flow rates of 40-60 L/min. The Oxis Turbuhaler delivers the smaller particles as the Foradil P Aerolizer and, thus, the Formoterol deeper into the lungs, but the high specific airflow resistance will influence the ability of patients with severe asthma and children to use the system.


Asunto(s)
Agonistas Adrenérgicos beta/administración & dosificación , Etanolaminas/administración & dosificación , Nebulizadores y Vaporizadores , Adulto , Asma/tratamiento farmacológico , Niño , Fumarato de Formoterol , Humanos , Técnicas In Vitro , Pulmón , Tamaño de la Partícula , Polvos
4.
J Aerosol Med ; 15(1): 65-73, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12006147

RESUMEN

Efficient inhalation therapy depends on successful delivery of the drug to the lung. The efficacy of drug delivery is not only influenced by the characteristics of the inhalation device, but also by the patient's handling of the device and by the inspiratory maneuver achieved through the device. We analyzed the output characteristics of three different chlorofluorocarbon (CFC)-free breath-actuated inhalers for inhaled glucocorticosteroids (BUD Turbohaler, FP Diskus/Accuhaler and HFA-BDP Autohaler, respectively). Mass output and particle size distribution of drug aerosol delivered by the inhalers were determined depending on different inhalation parameters in vitro using an Andersen cascade impactor. We found that, beside the peak inspiratory flow (PIF), other factors such as flow acceleration and inhalation volume also have significant effects on aerosol generation with respect to mass output and particle size distribution. Thus, these parameters should be taken into account when a suitable device for an individual patient is to be selected. The dependency on inspiratory parameters was most pronounced for the dry powder inhalers. The Turbohaler showed by far the highest variance in particle output (fine particle fraction ranging from 3.4% to 22.1% of label claim), whereas the Diskus was less dependent on variations in inhalation (10.6% to 18.5% of label claim). The most constant aerosol output was found for the Autohaler, which also released the highest fine particle fraction (43.1% to 56.6% of label claim).


Asunto(s)
Antiinflamatorios/administración & dosificación , Nebulizadores y Vaporizadores , Administración por Inhalación , Adulto , Aerosoles , Androstadienos/administración & dosificación , Asma/tratamiento farmacológico , Beclometasona/administración & dosificación , Budesonida/administración & dosificación , Niño , Fluticasona , Humanos , Inhalación/fisiología , Pulmón/efectos de los fármacos , Pulmón/fisiología , Tamaño de la Partícula , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Mecánica Respiratoria
5.
Psychol Rep ; 65(3 Pt 1): 897-8, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2608848

RESUMEN

Examining the relationship between personal space and a stigmatizing artifact, a white cane, with 58 randomly selected subjects indicated that significantly more personal space was accorded a person with an apparent visual impairment.


Asunto(s)
Ceguera/psicología , Espacio Personal , Prejuicio , Distancia Psicológica , Conducta Espacial , Adulto , Humanos
6.
Physiol Chem Phys ; 7(2): 115-23, 1975.
Artículo en Inglés | MEDLINE | ID: mdl-1153524

RESUMEN

Natural abundance 13C nuclear magnetic resonance spectra, in D2O, were obtained for the following: pantoyl lactone, beta-alanine, cysteamine hydrochloride, cystamine dihydrochloride, calcium pantothenate, beta-aletheine oxalate, pantetheine, pantethine, pantetheine 4'-phosphate, oxypantetheine 4'-phosphate, desulfopantetheine 4'-phosphate, N-acetyl-aminodesthiopantetheine 4'-phosphate, adenosine 2',5'-diphosphate, adenosine 3',5'-diphosphate, and coenzyme A. A complete assignment of the 13C chemical shifts in the NMR spectrum of CoA is reported. Comparison of spectra indicates that CoA most likely exists in an extended conformation.


Asunto(s)
Coenzima A , Espectroscopía de Resonancia Magnética , Adenosina Difosfato , Alanina , Isótopos de Carbono , Cistamina , Cisteamina , Deuterio , Disulfuros , Lactonas , Mercaptoetilaminas , Panteteína/análogos & derivados , Ácido Pantoténico , Conformación Proteica
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