Colorimetric quantification of mRNA expression in rare tumour cells amplified by multiple ligation-dependent probe amplification

An enzyme-linked oligonucleotide assay (ELONA) for quantification of mRNA expression of five genes involved in breast cancer, extracted from isolated rare tumour cells and amplified by multiplex ligation-dependent probe amplification (MLPA) is presented. In MLPA, a multiplex oligonucleotide ligation assay is combined with a PCR reaction in which all ligation products are amplified by use of a single primer pair. Biotinylated probes complementary to each of the target sequences were immobilised on the surface of a streptavidin-coated microtitre plate and exposed to single-stranded MLPA products. A universal reporting probe sequence modified with horseradish peroxidase (URP–HRP) and complementary to a universal primer used during the MLPA step was further added to the surface-bound duplex as a reporter probe. Simultaneous addition of anchoring probe and target, followed by addition of reporter probe, rather than sequential addition, was achieved with no significant effect on sensitivity and limits of detection, but considerably reduced the required assay time. Detection limits as low as 20 pmol L⁻¹, with an overall assay time of 95 min could be achieved with negligible cross-reactivity between probes and non-specific targets present in the MLPA-PCR product. The same MLPA-PCR product was analysed using capillary electrophoresis, the technique typically used for analysis of MLPA products, and good correlation was observed. The assay presented is easy to carry out, relatively inexpensive, rapid, does not require sophisticated instrumentation, and enables quantitative analysis, making it very promising for the analysis of MLPA products.     

A comment to the nudged elastic band method

The minimum energy path (MEP) is an important reaction path concept of theoretical chemistry, and the nudged elastic band (NEB) method with its many facets is a central method to determine the MEP. We demonstrate in this comment that the NEB does not have to lead to a steepest descent pathway (as always assumed). In contrast, as long as it is used without spring forces, it can lead to a gradient extremal. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010     

Aqueous organic and redox-mediated redox flow batteries: a review

Redox flow batteries (RFBs) are among the most investigated technologies for large-scale energy storage applications. Since the first commercialization of all-vanadium RFB (in the early 90s), the technology has evolved towards the development of new systems. This review focuses on three innovative concepts including aqueous organic RFB (AO-RFB), dual-circuit RFB and redox solid booster–based RFB. We will highlight the recent advances in the last five years and discuss the main challenges encountered. Particularly, we focused on the use of redox-mediated process to reach higher energy density than conventional RFB.     

Computing the Canonical Representation of Constructible Sets

Constructible sets are needed in many algorithms of Computer Algebra, particularly in the GröbnerCover and other algorithms for parametric polynomial systems. In this paper we review the canonical form ofconstructible sets and give algorithms for computing it.     

Reaction of Organometallic Compounds with Polyfluorinated Benzene Derivatives: Synthesis of 1-[3-(2,4-Difluorobenzoyl)-Phenyl]-Propan-1-One

The abnormally high acidity of the aromatic proton placed between two fluorine atoms in the benzene ring renders the compounds with this substitution pattern incompatible with the conventional organometallic compounds in synthetic processes. The synthesis of 1-[3-(2,4-difluorobenzoyl)-phenyl]-propan-1-one via the Stille reaction is reported as a remedy.