Simple di- and trivanillates exhibit cytostatic properties toward cancer cells resistant to pro-apoptotic stimuli.

in Bioorganic & Medicinal Chemistry (2010), 18(11), 3823-33

A series of 33 novel divanillates and trivanillates were synthesized and found to possess promising cytostatic rather than cytotoxic properties. Several compounds under study decreased by >50% the ... [more ▼]

A series of 33 novel divanillates and trivanillates were synthesized and found to possess promising cytostatic rather than cytotoxic properties. Several compounds under study decreased by >50% the activity of Aurora A, B, and C, and WEE1 kinase activity at concentrations <10% of their IC(50) growth inhibitory ones, accounting, at least partly, for their cytostatic effects in cancer cells and to a lesser extent in normal cells. Compounds 6b and 13c represent interesting starting points for the development of cytostatic agents to combat cancers, which are naturally resistant to pro-apoptotic stimuli, including metastatic malignancies. [less ▲]

Simple formula for evaluating the fire resistance of axially loaded steel square hollow section columns filled with concrete

in Proceedings of the 1st International Conference on Modern Design, Construction and Maintenance of Structures (2007)

Simple heuristic model of an aerosol filter

in SFGP (Ed.) Récents Progrès en Génie des procédés - N°96 - Des réponses industrielles pour une société en mutation - Actes du 11ème Congrès de la Société francophone de Génie des Procédés, 9-11 octobre 2007, Saint-Etienne, France (2007)

A simple method for determination of electrospray response factors of noncovalent complexes: application to DNA G-quadruplex binding and self-assembly

Conference (2009, June 04)

Introduction Electrospray mass spectrometry (ESI-MS) is now widely used to investigate non-covalent assemblies, and the power of the method resides in the individual detection of the various ... [more ▼]

Introduction Electrospray mass spectrometry (ESI-MS) is now widely used to investigate non-covalent assemblies, and the power of the method resides in the individual detection of the various stoichiometries present in the mixture. However, to characterize the mixture quantitatively (i.e. to determine the concentration of each constituent), the biggest challenge comes from the fact that electrospray response factors of all constituents can be different, especially for constituents of significantly different masses and charges. Here we present a novel and simple method to determine the response factors of all constituents, using an internal standard. The method can be transposed to a wide variety of biological problems and to different ionization methods. Experimental All oligodeoxynucleotides were purchased from Eurogentec (Seraing, Belgium). G-quadruplexes formation is induced by addition of ammonium acetate (150 mM) to the guanine-rich strand. Polythymines (e.g. dT6) with m/z not overlapping with those of the complexes were used as internal standards. The ESI mass spectra were acquired using a Q-TOF Ultima Global (Waters, Manchester, UK) in the negative ion mode, with source parameters optimized for detecting the intact complexes. Quadruplex-ligand binding constants were quantified by titration of the quadruplex with the ligand (BOQ1, Dr. Teulade-Fichou). The kinetics of G-quadruplex self-assembly was monitored on-line, with the starting time defined by the addition of ammonium to the single strand. Peak areas were calculated using MassLynx and data were processed using Mathcad. Preliminary results Let us illustrate the method for the characterization of the self-assembly of dCGGTGGT. In NH4OAc, this G-rich strand forms a tetramer within a few hours, but the most stable species is an octamer, which is formed after a few days. The relative intensities of monomer, tetramer and octamer vary with the experimental settings: harsher conditions favor the transmission of the larger complexes. It is therefore foolish to assume that the response factors of the monomer, tetramer and octamer are equal. Using dT6 as an internal reference, we monitored the self-assembly kinetics by recording at several time points the following intensities: I(ref2-), I(G12-), I(G45-) and I(G89-), where Gn indicates a complex containing n G-rich strands. For each species Gn, we define Rn as its response factor relative to that of the reference: [Gn]/[ref] = Rn * I(Gn)/I(ref). At each time point the mass balance equation for the strand concentration must be satisfied: [G]tot = [G1] + 4[G4] + 8[G8]. Substituting with the definition of Rn’s one obtains a set of equations: [G]tot = [ref] * {R1*(I(G1)/I(ref) + 4R4*I(G4)/I(ref) + 8R8*I(G8)/I(ref)}. If the number of equations (time points) is greater than the number of unknown response factors, the least-squares fit to this system of equations is calculated using the Moore-Penrose pseudoinverse of the matrix constituted by the intensity ratios. Once all response factors are known, concentrations are recalculated at each time point, providing detailed characterization of the reaction kinetics, including reaction intermediates. We will also show that the same method can be used to quantify ligand binding using titration of the substrate by the ligand. This will be illustrated with titration of the quadruplex (TGGGGT)4 by ligand BOQ1. This ligand binds to the quadruplex and also produces ligand-bridged quadruplex multimers, which the present method allows quantifying for the first time. [less ▲]

A simple method for the preparation of covalently closed circular form of plasmid DNA

in BioTechniques (1988)

We describe a simple, rapid, inexpensive method for isolation of covalently closed circular plasmid DNA. The method involves the electrophoresis of crude DNA preparations in an agarose gel ... [more ▼]

We describe a simple, rapid, inexpensive method for isolation of covalently closed circular plasmid DNA. The method involves the electrophoresis of crude DNA preparations in an agarose gel, electrotransfer onto a dialysis membrane and elution of the highly purified circular covalently closed plasmid DNA. Native and recombinant plasmid DNA have been purified by this method and shown to be suitable for restriction enzyme digestion and transformation of bacteria. The yield of this rapid purification procedure makes it a good alternative method to standard centrifugation in cesium chloride ethidium bromide gradients. [less ▲]

A simple method to approximate gene content in large pedigree populations: application to the myostatin gene in dual-purpose Belgian Blue cattle

in Animal (2007), 1(1), 21-28

Gene content is the number of copies of a particular allele in a genotype of an animal. Gene content can be used to study additive gene action of candidate gene. Usually genotype data are available only ... [more ▼]

Gene content is the number of copies of a particular allele in a genotype of an animal. Gene content can be used to study additive gene action of candidate gene. Usually genotype data are available only for a part of population and for the rest gene contents have to be calculated based on typed relatives. Methods to calculate expected gene content for animals on large complex pedigrees are relatively complex. in this paper we proposed a practical method to calculate gene content using a linear regression. The method does not estimate genotype probabilities but these can be approximated from gene content assuming Hardy-Weinberg proportions. The approach was compared with other methods on multiple simulated data sets for real bovine pedigrees of 1082 and 907 903 animals. Different allelic frequencies (0.4 and 0.2) and proportions of the missing genotypes (90, 70, and 50%) were considered in simulation. The simulation showed that the proposed method has similar capability to predict gene content as the iterative peeling method, however it requires less time and can be more practical for large pedigrees. The method was also applied to real data on the bovine myostatin locus on a large dual-purpose Belgian Blue pedigree of 235 133 animals. It was demonstrated that the proposed method can be easily adapted for particular pedigrees. [less ▲]

A simple model for generalised parton distributions of the pion

in Bruncko, D.; Ferencei, J.; Strizenec, P. (Eds.) 12th International Workshop On Deep Inelastic Scattering (DIS 2004) (2004)

A Simple Model for the Fire Resistance of Axially-Loaded Members According to Eurocode 3

in Journal of Constructional Steel Research (1995), 35

New buckling curves have been developed for axialy loaded steel members subjected to fire. The model is based on extensive numerical simulations calibrated on several dozens of full scale experimental ... [more ▼]

New buckling curves have been developed for axialy loaded steel members subjected to fire. The model is based on extensive numerical simulations calibrated on several dozens of full scale experimental test results. This model has been subsequently included in Eurocode 3. [less ▲]

Simple model for total cross sections

in Cooper, Fred; Sarcevic, Ina; West, Geoffrey (Eds.) THE STATE OF PHYSICS AT THE END OF THE 20TH CENTURY: In honor of Peter Carruthers (1997)

Simple observation au sujet du travail de M. W. Hallock(*) intitulé "the Flow of Solids, etc."

in Bulletin de l'Académie Royale des Sciences, des Lettres et des Beaux-arts de Belgique. Sciences. 3e série (1887), XIV(11), 595-598