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51.
NORA SCHWIND MICHÈLE ZWIEBEL ASUKA ITAYA BIAO DING MING-BO WANG GABI KRCZAL MICHAEL WASSENEGGER 《Molecular Plant Pathology》2009,10(4):459-469
Because of their highly ordered structure, mature viroid RNA molecules are assumed to be resistant to degradation by RNA interference (RNAi). In this article, we report that transgenic tomato plants expressing a hairpin RNA (hpRNA) construct derived from Potato spindle tuber viroid (PSTVd) sequences exhibit resistance to PSTVd infection. Resistance seems to be correlated with high-level accumulation of hpRNA-derived short interfering RNAs (siRNAs) in the plant. Thus, although small RNAs produced by infecting viroids [small RNAs of PSTVd (srPSTVds)] do not silence viroid RNAs efficiently to prevent their replication, hpRNA-derived siRNAs (hp-siRNAs) appear to effectively target the mature viroid RNA. Genomic mapping of the hp-siRNAs revealed an unequal distribution of 21- and 24-nucleotide siRNAs of both (+)- and (–)-strand polarities along the PSTVd genome. These data suggest that RNAi can be employed to engineer plants for viroid resistance, as has been well established for viruses. 相似文献
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53.
A. Pompon G. Gosselin M. C. Bergogne J. L. Imbach 《Nucleosides, nucleotides & nucleic acids》2013,32(1-2):465-466
Abstract Rationalization of the intrinsic structural factors which can influence retention times of anomeric D-xylo- and lyxofuranonucleoside analogues in reversed-phase high-performance liquid chromatography (HPLC) has been established. 相似文献
54.
Reconstitution in vitro of human gingiva 总被引:1,自引:0,他引:1
F Gosselin M Gervaise Y Neveux M M Portier 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1989,309(9):323-329
A model of human gingiva to be used in pharmacological, basic and clinical research was performed in vitro. This model was obtained through a method of low density seeding epithelialization, from a seeding made up of dissociated human gingiva epithelial cells, of a connective tissue equivalent composed of human fibroblasts included in a collagen gel. The histological and ultrastructural data show a multilayered epithelium and the biochemical analysis (two dimensional gel electrophoresis known as NEPHGE) of the cytokeratins used as molecular markers for epithelial differentiation shows the precise differentiation state of the epithelium thus reconstituted. Even though this model has less of a differentiation than that of an in vivo gingival epithelium, it does actually reproduce exactly the structures of the human gingiva namely a multilayered epithelium lying on a connective tissue. It also offers the advantage of cellular elements which are compatible with gingival graftings. 相似文献
55.
LE MAGNEN J 《Comptes rendus des séances de la Société de biologie et de ses filiales》1951,145(11-12):857-860
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57.
Anti-HIV Pronucleotides: SATE Versus Phenyl as a Protecting Group of AZT Phosphoramidate Derivatives
T. Beltran D. Egron I. Lefebvre C. Périgaud A. Pompon G. Gosselin 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):973-975
Abstract We comparatively studied the decomposition pathways in CEM cell extract of several PHENYL phosphoramidate diesters of AZT. A correlation between anti-HIV activities in TK? cell lines and pharmacokinetic data has been observed. This study would help to design corresponding SATE phosphoramidate diesters which revealed potent anti-HIV properties. 相似文献
58.
Gilles Gosselin Christophe Mathé Marie-Christine Bergogne Anne-Marie Aubertin Andre Kirn Jean-Pierre Sommadossi 《Nucleosides, nucleotides & nucleic acids》2013,32(3-5):611-617
Abstract Several L-enantiomers of nucleoside analogues were stereospecifically synthesized by a multi-step reaction from L-xylose and their antiviral properties were examined in vitro. Two of them, namely β-L-2′,3,′-dideoxycytidine (β-L-ddC) and its 5-fluoro derivative (β-L-FddC) were found to have potent anti-human immunodeficiency virus (HIV) and significant anti-hepatitis B virus (HBV) activities in cell cultures. 相似文献
59.
Abstract 3′-Deoxy-β-L-erythro- (3), 3′-deoxy-β-L-thero- (6), 2′-fluoro- (7) and 2′-azido-2′,3′-dideoxy-β-L-erythro- (10) pentofuranonucleoside derivatives of thymine have been synthesized and their antiviral properties examined. All these derivatives were stereospecifically prepared by glycosylation of thymine with a suitable peracylated 3-deoxy-L-erythro-pentofuranose sugar (1), followed by appropriate chemical modifications. The prepared compounds were tested for their activity against HIV, but they did not show an antiviral effect. 相似文献
60.
B. Gröschel N. Himmel J. Cinatl C. Périgaud G. Gosselin J-L. Imbach 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):921-926
Abstract A 2,3′-dideoxycytidine (ddC)-resistant T-lymphoid cell line (MOLT-4/8rddC250), in which deoxycytidine kinase (dCK) gene-expression was decreased when compared with parental cells, has been selected. Cytotoxic and antiretroviral activity of ddC and 3TC was significantly lower in MOLT-4/8rddC250 than in parental MOLT-4/8 cells. ddC- and 3TC-bis(SATE)phosphotriesters completely overcame cellular resistance mechanisms and showed comparable both cytotoxic and antiretroviral activity in parental and ddC-resistant cells. 相似文献