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41.
Maria Letizia Ciavatta Stella García‐Matucheski Marianna Carbone Guido Villani Maria Rosaria Nicotera Claudia Muniain Margherita Gavagnin 《化学与生物多样性》2017,14(9)
The lipophilic extracts of two marine aeolid nudibranch molluscs of the genus Spurilla collected in distinct geographical areas have been chemically analyzed. The Et2O extracts of the nudibranchs were dominated by the presence of usual fatty acids and sterols and contained terpenoid compounds 1 – 3 as minor metabolites. Spurillin A ( 1 ) and spurillin B ( 3 ) were new molecules whereas cis‐γ‐monocyclofarnesol ( 2 ) was already reported in the literature as a synthesis product. Interestingly, bursatellin ( 4 ), previously isolated from anaspidean molluscs of the genus Bursatella, was found in the butanol extract of both Spurilla species. Compounds 1 – 4 were not detected in the extracts of the sea‐anemone preys collected together with the molluscs. 相似文献
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Mugnaini C Manetti F Esté JA Clotet-Codina I Maga G Cancio R Botta M Corelli F 《Bioorganic & medicinal chemistry letters》2006,16(13):3541-3544
S-Aryl-S-DABO derivatives, a novel subclass of S-DABO anti-HIV-1 agents, were synthesized via Ullmann type reaction starting from the corresponding 2-thiouracils by the aid of microwave irradiation. The results of their evaluation as inhibitors of RT are reported together with their antiviral activity in cellular assays. 相似文献
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Stephan Fricke Manuela Ackermann Alexandra Stolzing Christoph Schimmelpfennig Nadja Hilger Jutta Jahns Guido Hildebrandt Frank Emmrich Peter Ruschpler Claudia P?sel Manja Kamprad Ulrich Sack 《PloS one》2009,4(7)
Background
Non adherent bone marrow derived cells (NA-BMCs) have recently been described to give rise to multiple mesenchymal phenotypes and have an impact in tissue regeneration. Therefore, the effects of murine bone marrow derived NA-BMCs were investigated with regard to engraftment capacities in allogeneic and syngeneic stem cell transplantation using transgenic, human CD4+, murine CD4−/−, HLA-DR3+ mice.Methodology/Principal Findings
Bone marrow cells were harvested from C57Bl/6 and Balb/c wild-type mice, expanded to NA-BMCs for 4 days and characterized by flow cytometry before transplantation in lethally irradiated recipient mice. Chimerism was detected using flow cytometry for MHC-I (H-2D[b], H-2K[d]), mu/huCD4, and huHLA-DR3). Culturing of bone marrow cells in a dexamethasone containing DMEM medium induced expansion of non adherent cells expressing CD11b, CD45, and CD90. Analysis of the CD45+ showed depletion of CD4+, CD8+, CD19+, and CD117+ cells. Expanded syngeneic and allogeneic NA-BMCs were transplanted into triple transgenic mice. Syngeneic NA-BMCs protected 83% of mice from death (n = 8, CD4+ donor chimerism of 5.8±2.4% [day 40], P<.001). Allogeneic NA-BMCs preserved 62.5% (n = 8) of mice from death without detectable hematopoietic donor chimerism. Transplantation of syngeneic bone marrow cells preserved 100%, transplantation of allogeneic bone marrow cells 33% of mice from death.Conclusions/Significance
NA-BMCs triggered endogenous hematopoiesis and induced faster recovery compared to bone marrow controls. These findings may be of relevance in the refinement of strategies in the treatment of hematological malignancies. 相似文献46.
Julia O. Sonsin Peter E. Gasson FLS Claudia F. Barros Carmen R. Marcati 《Botanical journal of the Linnean Society. Linnean Society of London》2012,170(2):257-276
A comparative study of the secondary xylem (wood) anatomy of 11 species (38 specimens) occurring in cerrado s.s. and the adjacent gallery forest (both cerrado s.l. habitat) was made with the aim of identifying the anatomical characteristics of ecological value and correlating them with the environmental conditions. The anatomical features that vary, in general, between the two habitats are: growth ring distinctness (well or poorly defined); tyloses and deposits (more abundant in cerrado specimens); gelatinous fibres (more evident in cerrado specimens and in different patterns between habitats); variation in paratracheal and banded parenchyma (more abundant in cerrado); and more cells per parenchyma strand in cerrado. In general, gallery forest specimens have wider vessels, fewer vessels per square millimetre and larger intervessel pits, indicating more efficient water conduction, whereas cerrado s.s. specimens are the opposite, with low vulnerability and mesomorphy indices, demonstrating greater safety under conditions of water stress. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, ?? , ??–??. 相似文献
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Claudia Götz Andreas Gratz Uwe Kucklaender Joachim Jose 《Biochimica et Biophysica Acta (BBA)/General Subjects》2012,1820(7):970-977
BackgroundAbnormally high activity of protein kinase CK2 is linked to various diseases including cancer. Therefore, the inhibition of CK2 is a promising therapeutic strategy to fight this disease.MethodsWe screened a library of synthetic molecules concerning their capacity to inhibit CK2. The activity of CK2 and their IC50 and Ki values were determined by a capillary electrophoresis assay. The effects of the inhibitor in a cell culture model were analyzed by cell counting, a viability assay, cytofluorimetry and Western blot.ResultsThe best CK2 inhibitor found in this screen was 6,7-dichloro-1,4-dihydro-8-hydroxy-4-[(4-methylphenylamino)methylen]dibenzo [b,d]furan-3(2H)-one, which we refer to as “TF”. TF showed tight binding to CK2 with low IC50 (29 nM) and Ki (15 nM) values. TF inhibited only seven out of 61 human kinases tested (> 70% inhibition). Incubation of LNCaP cells with 50 μM TF for 48 h decreased the intracellular CK2 activity by 50%, confirming that the inhibitor is membrane permeable. The decrease in activity was correlated with a severe reduction in cell viability. The reduction in cell viability is at least partly due to the induction of apoptosis.General significanceIn many cancers the protein kinase CK2 is significantly up-regulated and supports the neoplastic phenotype. New therapeutic strategies should be based on diverse reliable inhibitors to reverse the abnormal high levels to normal settings. 相似文献
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Zhang HC Ye H Conway BR Derian CK Addo MF Kuo GH Hecker LR Croll DR Li J Westover L Xu JZ Look R Demarest KT Andrade-Gordon P Damiano BP Maryanoff BE 《Bioorganic & medicinal chemistry letters》2004,14(12):3245-3250
A novel series of acyclic 3-(7-azaindolyl)-4-(aryl/heteroaryl)maleimides was synthesized and evaluated for activity against GSK-3beta and selectivity versus PKC-betaII, as well as a broad panel of protein kinases. Compounds 14 and 17c potently inhibited GSK-3beta (IC(50)=7 and 26 nM, respectively) and exhibited excellent selectivity over PKC-betaII (325 and >385-fold, respectively). Compound 17c was also highly selective against 68 other protein kinases. In a cell-based functional assay, both 14 and 17c effectively increased glycogen synthase activity by inhibiting GSK-3beta. 相似文献