RESUMEN
Parabolic mirrors with a high numerical aperture can be conveniently used to produce highly confined optical fields in the focal region. Furthermore, these fields can have interesting polarization behaviour due to the high numerical aperture. In particular, if the mirror is illuminated with a size matched radially polarized or azimuthally polarized doughnut mode, the electric field has in the focal region almost exclusively a longitudinal or a transverse polarization component. Such field distributions are interesting for applications in confocal or near-field optical microscopy. Here we present experimental results where we have probed some of these field distributions by raster scanning a fine gold tip in nanometer steps through the focal region and detecting the scattered light intensity. The measured intensity patterns are compared with corresponding vector-field calculations.
RESUMEN
SM-20 is a novel, evolutionarily conserved "early response" gene originally cloned from a rat aortic smooth muscle cell (SMC) cDNA library. SM-20 encodes a cytoplasmic protein, which is induced by platelet-derived growth factor and angiotensin II in cultured SMC and is upregulated in intimal SMC of atherosclerotic plaques and injured arteries. We have now examined SM-20 expression during differentiation of cultured skeletal myoblasts and during skeletal myogenesis in vivo. Low levels of SM-20 mRNA and protein were expressed in proliferating mouse C2C12 myoblasts. Differentiation by serum withdrawal was associated with a marked induction of SM-20 mRNA and the expression of high levels of SM-20 antigen in myotubes. The induction was partially inhibited by blocking differentiation with bFGF or TGFbeta. Similar results were obtained with the nonfusing mouse C25 myoblast line, suggesting that SM-20 upregulation is a consequence of biochemical differentiation and is fusion independent. During mouse embryogenesis, SM-20 was first observed at 8.5E in the dermomyotomal cells of the rostral somites. SM-20 expression progressed in a rostral to caudal pattern, with highest levels seen in the muscle primordia and mature muscles. SM-20 thus represents a novel intracellular protein that is regulated during skeletal muscle differentiation and development.
Asunto(s)
Proteínas de Unión al ADN , Regulación del Desarrollo de la Expresión Génica , Proteínas Inmediatas-Precoces/metabolismo , Músculo Esquelético/embriología , Músculo Esquelético/metabolismo , Animales , Células Cultivadas , Prolina Dioxigenasas del Factor Inducible por Hipoxia , Proteínas Inmediatas-Precoces/genética , Inmunohistoquímica , Ratones , Ratones Endogámicos , Músculo Esquelético/citología , Procolágeno-Prolina Dioxigenasa , Regulación hacia ArribaRESUMEN
A woman whose serum contained multiple alloantibodies delivered a full-term infant with mild hemolytic disease of the newborn. The direct antiglobulin test performed on the cord cells was positive with monospecific anti-IgG. An acid elution performed on the cord cells yielded anti-Cob. These findings were consistent with the presence of anti-Cob in the maternal serum. Neonatal clinical findings showed a mildly affected infant who demonstrated a moderate rise in total bilirubin and slight jaundice. The infant experienced no further complications and was discharged.