Aquaporin functionality in roots of Zea mays in relation to the interactive effects of boron and salinity.

Zea mays L. cv. amylacea, a plant tolerant of B and salinity, was used to determine the involvement of aquaporin functionality in the interactive effects of B and salinity. Also, growth, chlorophyll concentration, and water relations were studied. While growth and chlorophyll concentration did not show noticeable changes under saline conditions, the decrease in leaf water potential and osmotic potential, together with the marked decrease of stomatal conductance and root hydraulic conductance, showed that the plants were adjusted osmotically. However, no effect of B was observed. The very weak response of the Lpc of salt-stressed roots to Hg suggested that water channels were greatly reduced in number or, if present, were non-functional. The evidence that substantial B movement can occur through diffusion and channel-mediated transport is compelling, and could account for B uptake under conditions of adequate or greater B supply. Therefore, the reduction in the functionality of aquaporins for NaCl-treated plants could be related to the reduction of B concentrations in roots and leaves in B + NaCl-treated plants, in comparison with plants treated only with B.

Evaluación ecocardiográfica de la valvuloplastia mitral con anillo de Carpenter / Echocardiographic evaluation of Carpenter ring mitral valvuloplasty

Se compararon los Ecocardiogramas pre y postoperatorios, de 13 pacientes sometidos a valvuloplastía con anillo de Carpentier, con insuficiencia mitral pura, su mayoría de origen reumático. Las variaciones obtenidas entre el pre y postoperatorio mediante Eco M de los diámetros de las distintas cavidades de VM fueron los siguientes: aurícula izquierda 70/52, diámetro diastólico de ventrículo izquierdo 66/53, diámetro sistólico de ventrículo izquierdo 48/38, excursión mitral 26/29, pendiente EF 95/45, (p<0.005). 9 pacientes fueron estudiados con ecocardiograma bidimensional en el pre y postoperatorio obteniendo los siguientes resultados: área de aurícula izqda. 39/30, área válvula mitral 5.18/2.91 (p<0.005). 6 pacientes se revaluaron con estudio hemodinámico y angiográfico, por presencia de soplo de regurgitación mitral encontrándose en todos ellos reducciomnes significativas de las variables estudiadas