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671.
Tünde Molnár Árpád Dobolyi Gabriella Nyitrai Péter Barabás László Héja Zsuzsa Emri Miklós Palkovits Julianna Kardos 《BMC neuroscience》2011,12(1):1-17
Background
Late cerebral ischemia carries high morbidity and mortality after subarachnoid hemorrhage (SAH) due to reduced cerebral blood flow (CBF) and the subsequent cerebral ischemia which is associated with upregulation of contractile receptors in the vascular smooth muscle cells (SMC) via activation of mitogen-activated protein kinase (MAPK) of the extracellular signal-regulated kinase (ERK)1/2 signal pathway. We hypothesize that SAH initiates cerebrovascular ERK1/2 activation, resulting in receptor upregulation. The raf inhibitor will inhibit the molecular events upstream ERK1/2 and may provide a therapeutic window for treatment of cerebral ischemia after SAH.Results
Here we demonstrate that SAH increases the phosphorylation level of ERK1/2 in cerebral vessels and reduces the neurology score in rats in additional with the CBF measured by an autoradiographic method. The intracisternal administration of SB-386023-b, a specific inhibitor of raf, given 6 h after SAH, aborts the receptor changes and protects the brain from the development of late cerebral ischemia at 48 h. This is accompanied by reduced phosphorylation of ERK1/2 in cerebrovascular SMC. SAH per se enhances contractile responses to endothelin-1 (ET-1), 5-carboxamidotryptamine (5-CT) and angiotensin II (Ang II), upregulates ETB, 5-HT1B and AT1 receptor mRNA and protein levels. Treatment with SB-386023-b given as late as at 6 h but not at 12 h after the SAH significantly decreased the receptor upregulation, the reduction in CBF and the neurology score.Conclusion
These results provide evidence for a role of the ERK1/2 pathway in regulation of expression of cerebrovascular SMC receptors. It is suggested that raf inhibition may reduce late cerebral ischemia after SAH and provides a realistic time window for therapy. 相似文献672.
Francesca D'Anna Vincenzo Frenna Susanna Guernelli Gabriella Macaluso Salvatore Marullo Domenico Spinelli 《Journal of Physical Organic Chemistry》2008,21(4):306-314
A kinetic investigation in methanol of the title reaction has evidenced the occurrence of two processes: the 1‐ E 1‐ Z isomerization and the rearrangement of the (Z)‐isomer into the relevant 4‐benzoylamino‐2,5‐diphenyl‐1,2,3‐triazole ( 1‐ Z → T ). The latter reaction is in line with the ability of the (Z)‐phenylhydrazones of 3‐benzoyl‐1,2,4‐oxadiazoles to undergo the so called mononuclear rearrangement of heterocycles (MRH). The occurrence of both the examined reactions is dependent on a Lewis‐acid‐catalysis. The obtained results have shown the possibility of a ‘new’ type of acid‐catalysis (bifunctional catalysis by Lewis salts) in the MRH. This catalysis operates through a completely different mechanism with respect to the one recently observed, and deeply investigated, in the presence of protic acids for the (Z)‐phenylhydrazone of 5‐amino‐3‐benzoyl‐1,2,4‐oxadiazole, in both dioxane/water and toluene, for which the catalytic process was dependent on the protonation of N(4) ring‐nitrogen of the 1,2,4‐oxadiazole. As a matter of fact, the copper salts seem able to interact with the >C?N? NH? C6H5 moiety, yielding adducts which, in some cases, are prone to both isomerize and rearrange. Therefore, a similar behaviour in some manner parallel to that already observed in benzene in the presence of aliphatic amines (base‐catalysis) has been evidenced. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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Yingjuan Cao Dr. Luca Gabrielli Dr. Diego Frezzato Prof. Dr. Leonard J. Prins 《Angewandte Chemie (International ed. in English)》2023,62(4):e202215421
We show the formation of macroscopic ATP-concentrations in an agarose gel and demonstrate that these gradients can be sustained in time at the expense of the consumption of a chemical fuel. The approach relies on the spatially controlled activation of ATP-producing and ATP-consuming reactions through the local injection of enzymes in the matrix. The reaction-diffusion system is maintained in a stationary non-equilibrium state as long as chemical fuel, phosphocreatine, is present. The reaction-diffusion system is coupled to a supramolecular system composed of monolayer protected gold nanoparticles and a fluorescent probe. As a result of this coupling, fluorescence signals emerge spontaneously in response to the ATP-concentration gradients. We show that the approach permits the rational formation of complex fluorescence patterns that change over time as a function of the evolution of the ATP-concentrations present in the system. 相似文献
676.
Ovari Tamara-Rita Katona Gabriel Coros Maria Szabó Gabriella Muresan Liana Maria 《Journal of Solid State Electrochemistry》2023,27(7):1795-1811
Journal of Solid State Electrochemistry - The aim of the paper is to carry out a detailed investigation of the effect of graphene oxide-poly(amidoamine) (GO-PAMAM) incorporated in silica matrices... 相似文献
677.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献