Search results for "oligo"
showing 10 items of 1298 documents
Antisense gene therapy using anti-k-ras and antitelomerase oligonucleotides in colorectal cancer
2005
Aim: to test the efficacy of anti-k-ras and antitelomerase oligonucleotides for disabling colorectal cancer cell growth. Material and methods: an established human colorectal cancer cell line (SW 480, ATTC ® ) was used. Oligodeoxiribonucleotides (ODNs) have a phosphorotioate modification to ensure intracellular intake. We used an antitelomerase ODN (Telp5) and two anti-k-ras ODNs (AS-KRAS and ISIS). AS-KRAS is designed to join the k-ras oncogene’s exon 1. ISIS links to the terminal transcription unit 5’ of k-ras. Telp5 joins the template region of the hTR telomerase subunit. ODNs have been tested in different concentrations (1, 5, 10, 20 micromolar). Cell viability has been tested at 48 and…
Multiple independent variants at the TERT locus are associated with telomere length and risks of breast and ovarian cancer
2013
Journal article TERT-locus SNPs and leukocyte telomere measures are reportedly associated with risks of multiple cancers. Using the Illumina custom genotyping array iCOGs, we analyzed ~480 SNPs at the TERT locus in breast (n = 103,991), ovarian (n = 39,774) and BRCA1 mutation carrier (n = 11,705) cancer cases and controls. Leukocyte telomere measurements were also available for 53,724 participants. Most associations cluster into three independent peaks. The minor allele at the peak 1 SNP rs2736108 associates with longer telomeres (P = 5.8 × 10!-7), lower risks for estrogen receptor (ER)-negative (P = 1.0 × 10!-8) and BRCA1 mutation carrier (P = 1.1 × 10!-5) breast cancers and altered promot…
New propylamine oligopyrrole carboxamides linked to a heterocyclic or anthraquinone system: synthesis, DNA binding, topoisomerase I inhibition and cy…
2003
Continuing our studies on combilexines, compounds consisting of a DNA intercalator linked to a minor groove ligand, new results are presented. The synthesis of a series of new propylamine oligopyrrole carboxamides closely related to netropsin and distamycin A, linked to a heterocyclic or anthraquinone system is reported. The cytotoxic activity in vitro, the DNA binding characteristics and the inhibition of the topoisomerase I of the compounds were studied in order to explain the biological mechanism of action of these new potential combilexines. Some of the synthesised compounds showed cytotoxic activity against human tumour cell lines, as well as DNA binding and topoisomerase I inhibiting …
Sperm imprinting integrity in seminoma patients?
2018
IF 4.990; International audience; BackgroundTesticular germ cell tumor such as seminoma is strongly associated with male reproductive problems commonly associated with the alteration of sperm parameters as described in testicular dysgenesis syndrome. Interestingly, numerous studies have reported that the precursor of germ cell cancer, germ cell neoplasia in situ (GCNIS), present similarities to fetal gonocytes, specifically characterized by global DNA hypomethylation particularly on imprinting sequences. These disorders may have a common origin derived from perturbations of embryonal programming during fetal development. Presently, there is no available information concerning the sperm DNA …
MIXED OLIGOPOLY, PRODUCT DIFFERENTIATION AND COMPETITION FOR PUBLIC TRANSPORT SERVICES*
2006
This paper explores frequency and pricing decisions in a horizontally and vertically differentiated duopoly when there is competition between means of transport and where one of the firms need not necessarily maximize profits. The private and the mixed duopoly are compared and distortions from the social optimum are identified, both analytically and numerically. A mixed duopoly does not recover the socially optimal solution. However, the presence of a (public) non-profit maximizing operator is a useful measure to get closer to the social optimum. When both operators are (private) profit maximizers, some control measures such as price caps and minimum service availability would reduce the di…
Quality and competition between public and private firms
2017
We study a multistage, quality-then-price game between a public firm and a private firm. The market consists of a set of consumers who have different quality valuations. The public firm aims to maximize social surplus, whereas the private firm maximizes profit. In the first stage, both firms simultaneously choose qualities. In the second stage, both firms simultaneously choose prices. Consumers’ quality valuations are drawn from a general distribution. Each firm's unit production cost is an increasing and convex function of quality. There are multiple equilibria. In some, the public firm chooses a low quality, and the private firm chooses a high quality. In others, the opposite is true. We …
Taking firms’ margin targets seriously in a model of competition in supply functions
2022
We introduce price-markup objectives into a model of supply function competition. We characterize the corresponding supply-function equilibrium and study its qualitative properties. Adherence to price-markup targets is conducive to reduced market competition and increased firm profitability. While pursuing such goals reduces social welfare, welfare never drops below the level corresponding to a Cournot oligopoly. Finally, we establish conditions under which consumer preference for fair pricing inhibits the industry's use of markups as a collusive device.
Investigation of thermal stability of ethylene copolymers with POSS - Study under static and dynamic conditions
2018
Abstract In the paper there was studied thermal stability of a series of ethylene copolymers with monoalkenylsiloxy- or monoalkenylsilsesquioxanes (POSS) under dynamic and static conditions. The copolymers proved to be more thermally stable than neat polyethylene and neat silsesquioxane comonomers. The kind and the content of the POSS units significantly affected degradation of the copolymers. Thermal oxidation process resulted in structural changes of the (co)polymers as it was evidenced by the variations in the kind and content of carbonyl, as well as by unsaturated end groups. Depending on the structure of the POSS comonomer incorporated into the polymer chain, the silsesquioxane units o…
Modulation of 2′-5′oligoadenylate synthetase by environmental stress in the marine spongeGeodia cydonium
1997
Recently we established the presence of relatively high amounts of 2′-5′oligoadenylates (2′-5′A) and 2′-5′oligoadenylate synthetase (2′-5′A synthetase) in the marine sponge Geodia cydonium. Here we determined by applying radioimmunoassay and high-performance liquid chromatographical methods that the concentration of 2′-5′A and the activity of 2′-5′A synthetase change following exposure of G. cydonium tissue to environmental stress. The 2′-5′A content and the activity of 2′-5′A synthetase, present in crude sponge extract, increase by up to three-fold after treating sponge cubes for 2 h with natural stressors including heat shock (26°C), cold shock (6°C), pH shock (pH 6), and hypertonic shock…
Efficient Conversion of Carbon Dioxide by Imidazolium-Based Cross-Linked Nanostructures Containing Polyhedral Oligomeric Silsesquioxane (POSS) Buildi…
2019
Polyhedral oligomeric silsesquioxanes (POSS) have been employed as molecular building blocks for the synthesis of imidazolium cross-linked networks, to be used as heterogeneous catalysts for the conversion of carbon dioxide into cyclic carbonates. Two hybrid materials with different nucleophilic species (bromide and iodide) have been prepared and characterized by means of elemental analysis, 13C and 29Si solid-state NMR spectroscopy, thermogravimetric analysis and IR spectroscopy. The solids were tested as the sole catalyst under metal- and solvent-free reaction conditions showing full selectivity toward the formation of cyclic carbonates. High turnover number (TON) and productivity values,…