0000000000395697
AUTHOR
R. Pascual
El uso de órdenes con volumen oculto en el Sistema de Interconexión Bursátil Español
ResumenMuchos mercados dirigidos por órdenes permiten a sus participantes introducir órdenes límite en las que no se revela el tamaño completo de la orden. En este artículo, se describe la utilización de este tipo de órdenes en el mercado español de acciones. Se muestra que una de cada cinco transacciones realizadas en el mercado español implica la detección de volumen oculto. La contribución del volumen oculto al proceso de negociación es más importante entre las acciones menos líquidas, y durante períodos de elevado riesgo de exposición de las órdenes limite. Además, se muestra que los usuarios de este tipo de órdenes se comportan como cazadores de tendencias y siguen un comportamiento im…
Relaxation by Calcium Antagonists of Potassium-contracted Trachea from Normal and Sensitized Guinea-pigs: Influence of Epithelium and the Surface of Drug Entry
Abstract A technique by which drug access was restricted to either the mucosal or the adventitial surface of tracheal rings, isolated from normal (unsensitized) or sensitized guinea-pigs, was used to study the role of the epithelium in the relaxation produced by calcium antagonists (verapamil, nifedipine, cinnarizine and flunarizine) of K+-induced contraction. In trachea from normal guinea-pigs, the relaxation to verapamil for unrestricted or mucosal drug entry was reduced in the absence of epithelium, whereas the relaxation produced by nifedipine, cinnarizine or flunarizine was unchanged. In sensitized trachea, the relaxation elicited by the calcium antagonists tested was similar in intact…
Effects of sensitization on vasoactive intestinal polypeptide-induced relaxation and its concentration and binding in guinea-pig airways.
We investigated the relaxant effect of vasoactive intestinal polypeptide (VIP) in trachea and lung parenchyma from normal and sensitized guinea-pigs. A technique by which drug access was restricted to either the mucosal or the adventitial surface of tracheal rings was used. In intact trachea, concentration-response curves for VIP entering from the mucosal surface (pD2 = 6.61 +/- 0.06) were displaced to the right compared with those for adventitial entry (pD2 = 6.78 +/- 0.04). Epithelium removal produced a leftward shift (approximately 2.8-fold) in the mucosal VIP concentration-response curve. Sensitization did not alter the responsiveness (maximal effect) or sensitivity (pD2 values) of trac…
Human Immunodeficiency Virus Continuum of Care in 11 European Union Countries at the End of 2016 Overall and by Key Population: Have We Made Progress?
Abstract Background High uptake of antiretroviral treatment (ART) is essential to reduce human immunodeficiency virus (HIV) transmission and related mortality; however, gaps in care exist. We aimed to construct the continuum of HIV care (CoC) in 2016 in 11 European Union (EU) countries, overall and by key population and sex. To estimate progress toward the Joint United Nations Programme on HIV/AIDS (UNAIDS) 90-90-90 target, we compared 2016 to 2013 estimates for the same countries, representing 73% of the population in the region. Methods A CoC with the following 4 stages was constructed: number of people living with HIV (PLHIV); proportion of PLHIV diagnosed; proportion of those diagnosed …
Role of endothelium in the responses to noradrenaline in normal and sensitized guinea-pig aorta
1. The pharmacological reactivity of sensitized blood vessels has been less studied than that of the airways. Aorta rings were obtained from normal (non-sensitized) and actively sensitized guinea-pigs, and prepared for isometric recording of tension changes. 2. Noradrenaline (10 nM-0.1 mM), histamine (0.1 microM-0.1 mM) and KCl (10-100 mM) produced concentration-related contractions of normal tissues. Removal of endothelium resulted in a marked leftward and upward shift of the concentration-response curve for noradrenaline but it did not alter histamine- or KCl-induced responses. Pretreatment with L-NG-nitroarginine (L-NOARG, 30 microM), haemoglobin (5 microM) or ibuprofen (10 microM) enhan…
Role of epithelium in agonist-induced contractile responses of guinea-pig trachealis: influence of the surface through which drug enters the tissue.
1. A method has been used in guinea-pig isolated tracheal rings to achieve selective drug entry from the adventitial or mucosal surface. A study has been made of the effects of epithelium removal on responses to spasmogens entering the tissue solely from the adventitial or the mucosal surface. 2. Cumulative concentration-response curves for KCl (1 to 100 mM), acetylcholine (0.1 microM to 10 mM) and histamine (1 microM to 1 mM) were constructed in intact and epithelium-denuded tracheal rings in circumstances where drug entry was unrestricted or restricted to the adventitial or mucosal surface. 3. Epithelium removal did not alter the responsiveness or sensitivity of tracheal rings to KCl eith…
Epithelium modulates the reactivity of sensitized guinea-pig trachea: influence of the surface of drug entry.
Abstract A technique by which drug access was restricted to either the mucosal or the adventitial surface of tracheal rings isolated from sensitized guinea-pigs was applied to study the role of the epithelium in modulating responses to KCl, acetylcholine, histamine and antigen (bovine serum albumin, BSA). Epithelium removal did not alter the responsiveness or sensitivity of tracheal rings to KCl. In contrast, a leftward shift occurred for concentration-response curves to acetylcholine (concentration ratio (CR) = 4·1), histamine (CR = 2·9) and BSA (CR = 33·9) entering from the mucosal surface of de-epithelialized trachea. This shift was not associated with changes in the maximal effect of th…