RESUMEN
Speech and language therapy is essential in the rehabilitation of aphasic disorders following a stroke. Due to the predicted increase of aphasia and limited resources within the healthcare system, the development of efficient and sustainable treatment methods is of exceptional importance. The effectiveness of both traditional and innovative approaches needs to be evaluated against the standards of evidence-based medicine. Class I evidence has been established for high-intensity speech and language therapy in subacute and chronic stages of aphasia. Innovative training-based approaches have so far only been evaluated in small studies but promising results have been shown for computer-based naming, video-based exercises for verbalization of complex contents and approaches modeled according to "forced-use" principles with standardized contents. Adjuvant training therapies are being developed to increase and prolong the impact of training alone, most notably non-invasive brain stimulation and pharmacological modulation. Transcranial direct current stimulation has been shown to effectively enhance training in several small randomized controlled trials but several questions still remain to be answered, including the location of electrode placement as well as the length and intensity of stimulation. Mixed evidence has been collected for the effectiveness of pharmacotherapy on speech learning and further randomized controlled trials are also needed to allow more firmly based recommendations.
Asunto(s)
Afasia/rehabilitación , Terapia del Lenguaje/métodos , Evaluación de Resultado en la Atención de Salud/métodos , Logopedia/métodos , Terapia Asistida por Computador/métodos , Estimulación Transcraneal de Corriente Directa/métodos , Afasia/diagnóstico , Medicina Basada en la Evidencia/métodos , Humanos , Resultado del TratamientoRESUMEN
Nanoparticles consisting of a polystyrene core and a polyglycidyl methacrylate shell were prepared by a two-step emulsion polymerization. The size and surface properties of the particles were characterized by scanning electron microscopy, dynamic light scattering and polyelectrolyte titration techniques. Particles were found to be monodisperse with a mean diameter of about 85 nm. Parent particles were modified with a number of different ligands including diamines of increasing chain length, amino acids and corresponding amines and higher molecular weight ligands like polymyxin B. The modified particles were tested for their endotoxin (ET) binding capacity in water and physiological sodium chloride solution with the Limulus amebocyte lysate (LAL) assay. It was found that the ET binding properties of the different ligands depend both on the ability of the ligand to form Coulomb- and van der Waals-interactions with the ET molecule influenced by the nature of the suspension medium. Therefore, the choice of ligands for particle modification has to consider minutely the conditions under which ET has to be removed, e.g. removal from pure water, dialysis fluids, plasma or blood.
Asunto(s)
Materiales Biocompatibles , Endotoxinas , Ácidos Polimetacrílicos/química , Poliestirenos/química , Emulsiones , Indicadores y Reactivos , Ligandos , Microscopía Electrónica de Rastreo , Ácidos Polimetacrílicos/síntesis química , Polimixina B , Poliestirenos/síntesis química , Unión Proteica , Soluciones , AguaRESUMEN
Particles with specific ligands for the adsorption of plasma proteins can be used in therapeutic or preparative apheresis. The development of these particles may benefit from an improved knowledge of the relationship between protein adsorption and the structure of ligands. Nanoparticles were functionalized with aliphatic diamines of increasing chain length; with the amino acids lysine, tryptophan, histidine, and their corresponding amines; and with tryptophan and histidine spaced with diamines of different length. Suitable protocols were developed for the washing of particles and the subsequent desorption of proteins adsorbed from human plasma. The adsorption pattern, as well as the quantification of the overall adsorption of proteins on these modified particles, was investigated with gel electrophoresis. This was followed by immunoblotting which yielded specific assessments of bound human serum albumin and fibrinogen. The comparison of protein adsorption with surface charge density and measured hydrophobicities yielded no simple correlations although in general more hydrophobic ligands bound higher quantities of protein. The detection of human serum albumin yielded similar results because it was observed for overall protein adsorption while the adsorption of fibrinogen expressed a different pattern. In this case, particular nanoparticles functionalized with aliphatic diamines bound significantly higher amounts of fibrinogen than all other ligands.