Effects of antenatal betamethasone on preterm human and mouse ductus arteriosus: comparison with baboon data.

BackgroundAlthough studies involving preterm infants ≤34 weeks gestation report a decreased incidence of patent ductus arteriosus after antenatal betamethasone, studies involving younger gestation infants report conflicting results.MethodsWe used preterm baboons, mice, and humans (≤276/7 weeks gestation) to examine betamethasone's effects on ductus gene expression and constriction both in vitro and in vivo.ResultsIn mice, betamethasone increased the sensitivity of the premature ductus to the contractile effects of oxygen without altering the effects of other contractile or vasodilatory stimuli. Betamethasone's effects on oxygen sensitivity could be eliminated by inhibiting endogenous prostaglandin/nitric oxide signaling. In mice and baboons, betamethasone increased the expression of several developmentally regulated genes that mediate oxygen-induced constriction (K+ channels) and inhibit vasodilator signaling (phosphodiesterases). In human infants, betamethasone increased the rate of ductus constriction at all gestational ages. However, in infants born ≤256/7 weeks gestation, betamethasone's contractile effects were only apparent when prostaglandin signaling was inhibited, whereas at 26-27 weeks gestation, betamethasone's contractile effects were apparent even in the absence of prostaglandin inhibitors.ConclusionsWe speculate that betamethasone's contractile effects may be mediated through genes that are developmentally regulated. This could explain why betamethasone's effects vary according to the infant's developmental age at birth

When virtual and material worlds collide: democratic fashion in the digital age

This paper explores the impact of the digitally-mediated communications technologies on the fashion sector. It argues that material and virtual fashion worlds are perpetually intersecting social realities that co-exist relationally, simultaneously and in mutual connection. The paper explores these shifting fashion landscapes in three particular ways in order to understand how fashion worlds are being transformed, enhanced and reproduced in space and time. Firstly, the paper argues that emergent digital technologies are remediating and refashioning existing cultural forms of signification such as fashion magazines and photography. Secondly, the article explores the potential disintermediatory effects that the internet is having on fashion markets and consumption, questioning to what extent digital technologies are enabling the devolution of fashion authority from traditional power-brokers such as magazine editors and designers towards a more diversified assemblage of participants, including fashion bloggers and consumers. Finally, the paper explores the transformative effects that digital technology is having on fashion consumption. The internet has opened up new spaces of fashion consumption that are unprecedented in their levels of ubiquity, immersion, fluidity and interactivity. Fashion spaces are increasingly portable, must follow us around, travel with us through time and space. The network effects made possible by the internet are enabling the creation of always-on, always connected consumer communities. Increasingly we are adrift without the internet, not with it. This is generating new ways of being in space where the absence of physical presence becomes second nature. Taken together, the collision between virtual and material fashion spaces requires a fundamental rethink about the role of fashion production, consumption, knowledge and the laws of markets. KEYWORDS Fashion Blogging Consumption Internet Remediation Disintermediation Burberr