17 research outputs found
Atypical birdsong and artificial languages provide insights into how communication systems are shaped by learning, use and transmission
In this article, I argue that a comparative approach focusing on the cognitive capacities and behavioral mechanisms that underlie vocal learning in songbirds and humans can provide valuable insights into the evolutionary origins of language. The experimental approaches I discuss use abnormal song and atypical linguistic input to study the processes of individual learning, social interaction, and cultural transmission. Atypical input places increased learning and communicative pressure on learners, so exploring how they respond to this type of input provides a particularly clear picture of the biases and constraints at work during learning and use. Furthermore, simulating the cultural transmission of these unnatural communication systems in the laboratory informs us about how learning and social biases influence the structure of communication systems in the long run. Findings based on these methods suggest fundamental similarities in the basic socialâcognitive mechanisms underlying vocal learning in birds and humans, and continuing research promises insights into the uniquely human mechanisms and into how human cognition and social behavior interact, and ultimately impact on the evolution of language
Zolmitriptan: A Novel Portal Hypotensive Agent Which Synergizes with Propranolol in Lowering Portal Pressure
Objective: Only a limited proportion of patients needing pharmacological control of portal hypertension are hemodynamic
responders to propranolol. Here we analyzed the effects of zolmitriptan on portal pressure and its potential interaction with
propranolol.
Methods: Zolmitriptan, propranolol or both were tested in two rat models of portal hypertension: common bile duct
ligation (CBDL) and CCl4-induced cirrhosis. In these animals we measured different hemodynamic parameters including
portal venous pressure, arterial renal flow, portal blood flow and cardiac output. We also studied the changes in superior
mesenteric artery perfusion pressure and in arterial wall cAMP levels induced by zolmitriptan, propranolol or both.
Moreover, we determined the effect of splanchnic sympathectomy on the response of PVP to zolmitriptan.
Results: In both models of portal hypertension zolmitriptan induced a dose-dependent transient descent of portal pressure
accompanied by reduction of portal flow with only slight decrease in renal flow. In cirrhotic rats, splanchnic sympathectomy
intensified and prolonged zolmitriptan-induced portal pressure descent. Also, propranolol caused more intense and durable
portal pressure fall when combined with zolmitriptan. Mesenteric artery perfusion pressure peaked for about 1 min upon
zolmitriptan administration but showed no change with propranolol. However propranolol enhanced and prolonged the
elevation in mesenteric artery perfusion pressure induced by zolmitriptan. In vitro studies showed that propranolol
prevented the inhibitory effects of b2-agonists on zolmitriptan-induced vasoconstriction and the combination of
propranolol and zolmitriptan significantly reduced the elevation of cAMP caused by b2-agonists.
Conclusion: Zolmitriptan reduces portal hypertension and non-selective beta-blockers can improve this effect. Combinati
European guidelines on cardiovascular disease prevention in clinical practice: full text. Fourth Joint Task Force of the European Society of Cardiology and other societies on cardiovascular disease prevention in clinical practice (constituted by representatives of nine societies and by invited experts).
(1) The European Heart Health Charter advocates the development and implementation of comprehensive health strategies, measures and policies at European, national, regional and local level that promote cardiovascular health and prevent cardiovascular disease.
(2) These guidelines aim to assist physicians and other health professionals to fulfill their role in this endeavour, particularly with regard to achieving effective preventive measures in day-to-day clinical practice.
(3)They reflect the consensus arising from a multidisciplinary
partnership between the major European professional bodies represented