RESUMEN
Some biological microorganisms can crawl or swim due to coordinated motions of their cytoskeleton or the flagella located inside their bodies, which push the cells forward through intracellular forces. To date, there is no demonstration of synthetic systems propelling at low Reynolds number via the precise actuation of the material confined within an enclosing lipid membrane. Here, we report lipid vesicles and other more complex self-assembled biohybrid structures able to propel due to the advection flows generated by the actuated rotation of the superparamagnetic particles they contain. The proposed swimming and release strategies, based on cooperative hydrodynamic mechanisms and near-infrared laser pulse-triggered destabilization of the phospholipid membranes, open new possibilities for the on-command transport of minute quantities of drugs, fluid or nano-objects. The lipid membranes protect the confined substances from the outside environment during transportation, thus enabling them to work in physiological conditions.
Asunto(s)
Hidrodinámica , Lípidos , Magnetismo , Modelos Biológicos , Rotación , Vesículas Transportadoras/metabolismoRESUMEN
Se presenta un lactante con estridor congénito crónico y síntomas asociados que motivaron el estudio etiológico del mismo. La demora en la realización de la endoscopia respiratoria completa y el sesgo que la experiencia de los especialistas inicialmente consultados introdujo en la interpretación de los hallazgos radiológicos determinaron un diagnóstico incompleto y un manejo no terapéutico. La fibrobroncoscopia demostró laringomalacia, traqueomalacia y compresión traqueal extrínseca. La angio TC identificó la arteria innominada como causante de la compresión. Tras la evaluación por un equipo multidisciplinar se recomendó realizar una aortopexia que resultó curativa (AU)
A case of an infant with congenital chronic stridor and the etiological studies performed because of associated symptoms is presented. Diagnosis was incomplete and initial management was conservative due to the delayed complete flexible endoscopy of the respiratory tract and the limited experience of the specialists who were consulted. Endoscopy revealed laryngomalacia, tracheomalacia and extrinsic tracheal compression, which was due to innominate artery as angioCT revealed. Aortopexy, recommended by a multidisciplinary team, was curative (AU)
Asunto(s)
Humanos , Lactante , Masculino , Ruidos Respiratorios/etiología , Laringomalacia/diagnóstico , Traqueomalacia/diagnóstico , Tronco Braquiocefálico/anomalías , Ruidos Respiratorios/diagnóstico , Tronco Braquiocefálico/fisiopatología , Tronco Braquiocefálico/cirugía , Estenosis Traqueal/etiología , Tomografía Computarizada por Rayos X , Ruidos Respiratorios/genética , Ruidos Respiratorios/fisiopatología , Traqueomalacia/cirugía , Traqueomalacia/terapiaRESUMEN
The effects on the geometry structure, atomic charges and vibrational wavenumbers of the main different substituents in the 5th position of the uracil ring were analysed, and relationships were established. The 5-monosubstituted derivatives studied were 5-XU (X=F, Cl, Br, I, CH(3), NH(2), NO(2)). The geometry and vibrational wavenumbers were determined in these molecules. The FT-IR and Raman spectra were studied with the support of B3LYP calculations using several basis sets. Several general conclusions were underlined.