28 research outputs found
Controversy surrounding the increased expression of TGFβ1 in asthma
Asthma is a waxing and waning disease that leads to structural changes in the airways, such as subepithelial fibrosis, increased mass of airway smooth muscle and epithelial metaplasia. Such a remodeling of the airways futher amplifies asthma symptoms, but its etiology is unknown. Transforming growth factor β1 is a pleiotropic cytokine involved in many fibrotic, oncologic and immunologic diseases and is believed to play an essential role in airway remodeling that occurs in asthmatic patients. Since it is secreted in an inactive form, the overall activity of this cytokine is not exclusively determined by its level of expression, but also by extensive and complex post-translational mechanisms, which are all importanin modulating the magnitude of the TGFβ1 response. Even if TGFβ1 upregulation in asthma is considered as a dogma by certain investigators in the field, the overall picture of the published litterature is not that clear and the cellular origin of this cytokine in the airways of asthmatics is still a contemporaneous debate. On the other hand, it is becoming clear that TGFβ1 signaling is increased in the lungs of asthmatics, which testifies the increased activity of this cytokine in asthma pathogenesis. The current work is an impartial and exhaustive compilation of the reported papers regarding the expression of TGFβ1 in human asthmatics. For the sake of comparison, several studies performed in animal models of the disease are also included. Inconsistencies observed in human studies are discussed and conclusions as well as trends from the current state of the litterature on the matter are proposed. Finally, the different points of regulation that can affect the amplitude of the TGFβ1 response are briefly revised and the possibility that TGFβ1 is disregulated at another level in asthma, rather than simply in its expression, is highlighted
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Shadow money and the public money supply: the impact of the 2007-2009 financial crisis on the monetary system
This article explores the effects of the political reactions to the 2007–2009 financial crisis on the monetary system. It chimes in with the view that shadow banks create ‘shadow money’, i.e. private substitutes for bank deposits. The article analyses how the three main forms of shadow money – money market fund shares, overnight repurchase agreements and asset-backed commercial papers – were affected by the short-term government intervention and medium-term regulation during and after the 2007–2009 financial crisis in the United States. The analysis reveals that the measures taken between 2007 and 2014 integrated some shadow money forms in the public money supply. In the year after the Lehman collapse, the initially private shadow money supply was either publicly backstopped or de-monetised as it had broken par to bank deposits. The public backstops took on the form of emergency facilities established by the Federal Reserve and guarantees proclaimed by the Treasury. Those backstops imply that the public institutional framework to protect bank deposits was extended to some forms of shadow money during the crisis. This tendency has continued in post-crisis regulation. Accordingly, the 2007–2009 financial crisis has triggered a paradigmatic change in the monetary system, attributable to the political decisions of US authorities