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191.
Abstract Methylthioadenosine (MTA) has been converted into its 3′ naturally occurring isomer (xylosyl-MTA) via protection at 2′-OH, oxidation, reduction and deprotection. 相似文献
192.
Alessandro Chiarolini Maria Teresa Donato Maria Jose Gomez Lechon Mauro Pala Federico Valerio Margherita Ferro 《Biomarkers》2013,18(5):279-285
Cytochrome P450 1A1 CYP1A1 enzymatic activity was evaluated in cultured liver cells, and taken as a biological indicator of the presence of inducers of this isoform in urban airborne particulate matter fraction samples. It is known that CYP1A1 inducers can play an important role in the risk of mutagenesis and carcinogenesis by environmental pollution. A romatic polycyclic hydrocarbons PAH from urban air were collected in the city of Genoa Italy at two sites on two different days of the year. The objective of the study was to compare the inducibility of cultured rat hepatocytes with that of MH1C1 and FaO rat hepatoma cell lines after exposure to a PAH mixture and to a standard compound, such as benzo b fluoranthene B b F. Cytotoxic effects of the tested concentrations were evaluated by means of 3 4,5, dimenthylthyazol 2 yl 2,5 diphenyltetrazolium bromide MTT and lactate dehydrogenase release LDH tests, the potency of inducers by ethoxyresorufin O deethylase EROD assay. The results were in agreement in the three cellular systems: after exposure to the PAH mixture, an induction at low concentrations was observed; whereas no induction, but rather a decrease in activity was shown at higher concentrations; instead, the exposure to pure B b F showed a dose-response relationship in all cells, even at the highest doses. Such a difference between the toxicity of the complex mixture and that of the pure compound could be ascribed to the presence of drug metabolism inhibitors in the mixture, or to interactions between the original components and their metabolites. The finding that the cell lines responded to the CYP1A1 induction in a very efficient way gives further proof of the applicability of this system to environmental biomonitoring. 相似文献
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Musumeci D Bucci EM Roviello GN Sapio R Valente M Moccia M Bianchi ME Pedone C 《Molecular bioSystems》2011,7(5):1742-1752
In this work we report the design and synthesis of kinked oligonucleotide duplexes as potential inhibitors of HMGB1, a cytokine which triggers a broad range of immunological effects. We found that the designed ligands can interact with HMGB1, as evidenced by circular dichroism spectroscopy, and are able to block some extracellular effects induced by the protein, such as cellular proliferation and migration, as we demonstrated by in vitro biological assays. After selecting the most stable and active kinked duplex, we synthesized the corresponding PNA/DNA chimeric duplex which resulted to be more resistant to enzymatic degradation, and showed a biological activity comparable to that of the natural duplex. Preliminary in vivo assays in a mouse inflammatory model, showed a significant decrease of the mortality after administration of the PNA/DNA kinked duplex to LPS-treated mice. 相似文献
196.
David Cruz‐Garcia Maria Ortega‐Bellido Margherita Scarpa Julien Villeneuve Marko Jovic Marc Porzner Tamas Balla Thomas Seufferlein Vivek Malhotra 《The EMBO journal》2013,32(12):1717-1729
The BAR (Bin/Amphiphysin/Rvs) domain proteins arfaptin1 and arfaptin2 are localized to the trans‐Golgi network (TGN) and, by virtue of their ability to sense and/or generate membrane curvature, could play an important role in the biogenesis of transport carriers. We report that arfaptins contain an amphipathic helix (AH) preceding the BAR domain, which is essential for their binding to phosphatidylinositol 4‐phosphate (PI(4)P)‐containing liposomes and the TGN of mammalian cells. The binding of arfaptin1, but not arfaptin2, to PI(4)P is regulated by protein kinase D (PKD) mediated phosphorylation at Ser100 within the AH. We also found that only arfaptin1 is required for the PKD‐dependent trafficking of chromogranin A by the regulated secretory pathway. Altogether, these findings reveal the importance of PI(4)P and PKD in the recruitment of arfaptins at the TGN and their requirement in the events leading to the biogenesis of secretory storage granules. 相似文献
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Thomas Musich Vishal Thovarai David J. Venzon Venkatramanan Mohanram Iskra Tuero Leia K. Miller-Novak Sabrina Helmold Hait Mohammad Arif Rahman Ruth Hunegnaw Erin Huiting Wuxing Yuan Colm OhUigin Tanya Hoang Yongjun Sui Celia LaBranche David Montefiori Jenifer Bear Margherita Rosati Massimiliano Bissa Jay A. Berzofsky George N. Pavlakis Barbara K. Felber Genoveffa Franchini Marjorie Robert-Guroff 《Journal of virology》2020,94(24)
199.
A simple analytical procedure to test for differences in beta diversity among sets of plots has been recently presented. Here, we describe an improved randomization procedure that replaces the one previously proposed. This procedure consists of shuffling within-group dissimilarities among groups and disregarding between-group dissimilarities. By repeating this operation many times, a distribution of the test statistics under the null hypothesis of no differences in the mean plot-to-plot dissimilarities within groups is obtained. This procedure ensures that the correct null model is selected. To describe this new procedure, we used plant and water beetle (Coleoptera) data collected from 45 permanent ponds. Beta diversity was compared between plant and water beetle (Coleoptera) assemblages. 相似文献
200.
Russo Mattia Petropoulos Vasilis Molotokaite Egle Cerullo Giulio Casazza Anna Paola Maiuri Margherita Santabarbara Stefano 《Photosynthesis research》2020,144(2):221-233
Photosynthesis Research - The kinetics of excited-state energy migration were investigated by femtosecond transient absorption in the isolated Photosystem I-Light-Harvesting Complex I (PSI-LHCI)... 相似文献