Search results for "oligonucleotide"
showing 10 items of 418 documents
Pathogen-Mimicking MnO Nanoparticles for Selective Activation of the TLR9 Pathway and Imaging of Cancer Cells
2009
Here, design of the first pathogen-mimicking metal oxide nanoparticles with the ability to enter cancer cells and to selectively target and activate the TLR9 pathway, and with optical and MR imaging capabilities, is reported. The immobilization of ssDNA (CpG ODN 2006) on MnO nanoparticles is performed via the phosphoramidite route using a multifunctional polymer. The multifunctional polymer used for the nanoparticle surface modification not only affords a protective organic biocompatible shell but also provides an efficient and convenient means for loading immunostimulatory oligonucleotides. Since fluorescent molecules are amenable to photodetection, a chromophore (Rhodamine) is introduced …
Antisense Phosphorothioate Oligonucleotides to the p65 Subunit of NF-κB Abrogate Fulminant Septic Shock Induced byS. typhimuriumin Mice
2001
The aim of this study was to characterize the functional relevance of the transcription factor NF-κB in the pathogenesis of septic shock. BALB/c mice were infected with two wild-type (WT 1, WT 2) strains of S. typhimurium that induce NF-κB or an escape variant that lacks this ability (P21) at a dose of 1 × 109/animal, respectively. Furthermore, wild-type infected mice were treated with antisense oligonucleotides directed against NF-κB 24 h before and 3 or 6 h after infection, while mismatched oligonucleotides were used as controls. Subsequently, the clinical course, histological and immunological alterations were monitored. Infection with WT 1 and WT 2 strains led to lethal septic shock wit…
Analysis of the Molecular Dialogue Between Gray Mold (Botrytis cinerea) and Grapevine (Vitis vinifera) Reveals a Clear Shift in Defense Mechanisms Du…
2015
Mature grapevine berries at the harvesting stage (MB) are very susceptible to the gray mold fungus Botrytis cinerea, while veraison berries (VB) are not. We conducted simultaneous microscopic and transcriptomic analyses of the pathogen and the host to investigate the infection process developed by B. cinerea on MB versus VB, and the plant defense mechanisms deployed to stop the fungus spreading. On the pathogen side, our genome-wide transcriptomic data revealed that B. cinerea genes upregulated during infection of MB are enriched in functional categories related to necrotrophy, such as degradation of the plant cell wall, proteolysis, membrane transport, reactive oxygen species (ROS) genera…
Pollen-stigma adhesion in Brassica spp involves SLG and SLR1 glycoproteins.
1999
The adhesion of pollen grains to the stigma is the first step of pollination in flowering plants. During this step, stigmas discriminate between pollen grains that can and cannot be permitted to effect fertilization. This selection is operated by various constituents of the cell walls of both partners. Several genes structurally related to the self-incompatibility system that prevents self-pollination in Brassica spp are known to target their products into the stigma cell wall. We proposed previously that one of these genes, the one encoding the S locus glycoprotein (SLG)-like receptor 1 (SLR1), which is coexpressed with that encoding SLG, may participate in pollen-stigma adhesion. Here, we…
Influence of the xyloadenosine analogue of 2?,5?-oligoriboadenylate on poly(A)-specific, 2?,5?-oligoriboadenylate degrading 2?,3?-exoribonuclease and…
1984
The homogeneous poly(A)-specific 2′,3′-exoribonuclease from calf thymus gland, which cleaves both 3′,5′-and 2′,5′-linked oligoriboadenylates, does not degrade (xyloA2'p)2 xyloA, the xylofuranosyladenosine analogue of the 2-5A core. This oligonucleotide, which is supposed to enter intact cells rapidly, was found to possess an increased stability and an enhanced antiherpesvirus activity compared to the natural (A2'p)2A (Eppstein, D. A., Barnett, J. W., Marsh, Y. V., Gosselin, G. and Imbach, J.-L. (1983) Nature 302, 723–724). The poly(A) anabolic enzyme, poly(A) polymerase (Mn2+-dependent), from the same source, which is initiated by (A3'p)2A and its higher oligomers, does not accept 2–5A core…
Cationic polyaspartamide-based nanocomplexes mediate siRNA entry and down-regulation of the pro-inflammatory mediator high mobility group box 1 in ai…
2015
Abstract High-mobility group box 1 (HMGB1) is a nonhistone protein secreted by airway epithelial cells in hyperinflammatory diseases such as asthma. In order to down-regulate HMGB1 expression in airway epithelial cells, siRNA directed against HMGB1 was delivered through nanocomplexes based on a cationic copolymer of poly(N-2-hydroxyethyl)- d,l -aspartamide (PHEA) by using H441 cells. Two copolymers were used in these experiments bearing respectively spermine side chains (PHEA-Spm) and both spermine and PEG2000 chains (PHEA-PEG-Spm). PHEA-Spm and PHEA-PEG-Spm derivatives complexed dsDNA oligonucleotides with a w/w ratio of 1 and higher as shown by a gel retardation assay. PHEA-Spm and PHEA-P…
Size-dependent knockdown potential of siRNA-loaded cationic nanohydrogel particles.
2014
To overcome the poor pharmacokinetic conditions of short double-stranded RNA molecules in RNA interference therapies, cationic nanohydrogel particles can be considered as alternative safe and stable carriers for oligonucleotide delivery. For understanding key parameters during this process, two different types of well-defined cationic nanohydrogel particles were synthesized, which provided nearly identical physicochemical properties with regards to their material composition and resulting siRNA loading characteristics. Yet, according to the manufacturing process using amphiphilic reactive ester block copolymers of pentafluorophenyl methacrylate (PFPMA) and tri(ethylene glycol)methyl ether m…
Spectroscopic Studies of Oligonucleotide Adducts and Base Sequence Preference of Adducts Formed by the Stereoisomers of 7,8-Dihydroxy-9,10-epoxy-7,8,…
1996
Abstract 5′-d(CCTATAGATATCC) has been reacted with BPDE and the adducts derived from binding of BPDE to the exocyclic amino group of deoxyguanosine (dG) were studied with spectroscopic methods. The major dG-adducts of (+)- and (-)-anti-BPDE and a minor adduct of (+)-syn-BPDE showed the characteristics of trans-adducts. The major products formed with (+)- and (-)-syn-BPDE exhibit cis-adduct characteristics. Annealing of BPDE-modified oligonucleotides to complementary or partially complementary strands results in reduced fluorescence intensity in several cases and in others the intensity is markedly increased. These differences demonstrate that the adduct microenvironment is strongly influenc…
Cellular Uptake of DNA Block Copolymer Micelles with Different Shapes
2008
The cellular uptake of DNA block copolymer micelles composed of DNA-b-PPO in Caco-2 cells was studied. In particular it was investigated if the shape of micelle aggregates influences the internalization. Rod-like polymeric particles were taken up 12 times more efficiently than their spherical counter parts although they were composed of the same constituents. Furthermore, it was observed that internalization of all the micelle systems was more efficient than the pristine DNA controls. A cytotoxicity assay proved the non-toxic nature of DNA-b-PPO micelle aggregates.
Berberine inhibits cell growth and mediates caspase-independent cell death in human pancreatic cancer cells.
2010
Pancreatic cancer is one of the most aggressive human malignancies with an increasing incidence worldwide. In addition to the poor survival rates, combinations using gemcitabine as a backbone have failed to show any benefit beyond monotherapy. These facts underscore an urgent need for novel therapeutic options and motivated us to study the effect of berberine on pancreatic cancer cells. Here, we undertook an mRNA-based gene expression profiling study in order to get deeper insight into the molecular targets mediating the growth inhibitory effects of berberine on pancreatic cancer cells compared to normal ones. Twenty-four hours after treatment, berberine showed preferential selectivity towa…