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11.
Montuori N Bifulco K Carriero MV La Penna C Visconte V Alfano D Pesapane A Rossi FW Salzano S Rossi G Ragno P 《Cellular and molecular life sciences : CMLS》2011,68(14):2453-2467
The receptor (CXCR4) for the stromal-derived factor-1 (SDF1) and the urokinase-receptor (uPAR) are up-regulated in various tumors. We show that CXCR4-transfected cells migrate toward SDF1 on collagen (CG) and do not on vitronectin (VN). Co-expression of cell-surface uPAR, which is a VN receptor, impairs SDF1-induced migration on CG and allows migration on VN. Blocking fMLP receptors (fMLP-R), alpha-v integrins or the uPAR region capable to interact with fMLP-Rs, impairs migration of uPAR/CXCR4-transfected cells on VN and restores their migration on CG. uPAR co-expression also reduces the adherence of CXCR4-expressing cells to various components of the extracellular matrix (ECM) and influences the partitioning of beta1 and alpha-v integrins to membrane lipid-rafts, affecting ECM-dependent signaling. uPAR interference in CXCR4 activity has been confirmed in cells from prostate carcinoma. Our results demonstrate that uPAR expression regulates the adhesive and migratory ability of CXCR4-expressing cells through a mechanism involving fMLP receptors and alpha-v integrins. 相似文献
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Daniela Guerra Patrizia Romano C. Zambonelli 《Cellular and molecular life sciences : CMLS》1981,37(7):691-693
Summary In resting cells of diploidSaccharomyces cerevisiae strains sulfur dioxide induces at very high frequency: a) respiratory deficinet mutants: b) mutants with altered methionine metabolism. In growing cells the following kinds of mutants appear: a) revertants for respiration; b) mutants altered in the methionine metabolism; c) SO2-resistants. It is suggested that sulfur dioxide acts as a selective agent through the induction SO2-resistant mutantsAcknowledgments. This investigation was supported by grant of C.N.R., Roma. The authors are grateful to Prof. Domenico L. Palenzona for helpful comments and suggestions. 相似文献
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Tea Chieli Daniela Cocchi G. B. Fregnan E. E. Müller 《Cellular and molecular life sciences : CMLS》1980,36(4):463-465
Summary Oral administration of 2 neuroleptic drugs, haloperidol and LR511 induced in male rats a marked, dose-dependent and sustained rise of plasma prolactin. 相似文献
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Metapopulations are ecological models describing the interactions and the behavior of populations living in fragmented habitats. In this paper, metapopulations are modelled by means of dynamical probabilistic P systems, where additional structural features have been defined (e.g., a weighted graph associated with the membrane structure and the reduction of maximal parallelism). In particular, we investigate the influence of stochastic and periodic resource feeding processes, owing to seasonal variance, on emergent metapopulation dynamics. 相似文献
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Daniela Guerra Mirella Mochi Sandra Grazia D. L. Palenzona 《Cellular and molecular life sciences : CMLS》1979,35(8):1019-1020
Summary ADrosophila melanogaster line has been treated with ionizing radiations. The dose-response relationship has been studied upon separate treatment of male and female gametes. The results show that while the total survival is similar, at different developmental stages differences can be observed between progenies from treated male and female gametes. It is suggested that developmental patterns may affect the expression of induced mutations. 相似文献
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E. E. Müller A. Panerai Daniela Cocchi L. A. Frohman P. Mantegazza 《Cellular and molecular life sciences : CMLS》1973,29(7):874-876
Riassunto Il 2-desossi-d-glucosio somministrato nel ventricolo laterale del cervello del ratto provoca iperglicemia, inibizione della secrezione di insulina, iperfagia ed ipotermia a dosi che sono inefficaci per via sistemica.
MissesF. Ferrari, S. Bianchi andL. Scapellato provided skilful technical assistance. This investigation was supported by Grant No. 70.01788.04115.2380 of the Consiglio Nazionale delle Richerche, Italy. 相似文献
MissesF. Ferrari, S. Bianchi andL. Scapellato provided skilful technical assistance. This investigation was supported by Grant No. 70.01788.04115.2380 of the Consiglio Nazionale delle Richerche, Italy. 相似文献
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Small organic molecules recently emerged as a third class of broadly useful asymmetric catalysts that direct reactions to yield predominantly one chiral product, complementing enzymes and metal complexes. For instance, the amino acid proline and its derivatives are useful for the catalytic activation of carbonyl compounds via nucleophilic enamine intermediates. Several important carbon-carbon bond-forming reactions, including the Mannich reaction, have been developed using this approach, all of which are useful for making chiral, biologically relevant compounds. Remarkably, despite attempts, the simplest of all nucleophiles, acetaldehyde, could not be used in this way. Here we show that acetaldehyde is a powerful nucleophile in asymmetric, proline-catalysed Mannich reactions with N-tert-butoxycarbonyl (N-Boc)-imines, yielding beta-amino aldehydes with extremely high enantioselectivities-desirable products as drug intermediates and in the synthesis of other biologically active molecules. Although acetaldehyde has been used as a nucleophile in reactions with biological catalysts such as aldolases and thiamine-dependent enzymes, and has also been employed indirectly, its use as an inexpensive and versatile two-carbon nucleophile in asymmetric, small-molecule catalysis will find many practical applications. 相似文献