Expression of mTOR and downstream signalling components in the JEG-3 and BeWo human placental choriocarcinoma cell lines

This article has been made available through the Brunel Open Access Publishing Fund.Emerging data suggest that nutritional status and body weight are related to reproductive function, and nutrient imbalances during pregnancy lead to changes in the expression of fetal genes. Recent studies show that the mTOR acts as a placental growth signalling sensor and its expression is down-regulated in intrauterine growth restriction. To date, very little is known about the expression of this signalling pathway in choriocarcinoma, one of the most lethal germ cell cancers. In this study, cultures of fusigenic (BeWo) and non-fusigenic (JEG-3) human choriocarcinoma cell lines were used to investigate the expression of mTOR and its downstream signalling components. The effects of an inducer of syncytialisation (forskolin) on mTOR, eIF4E binding proteins (4EBPs) and ribosomal protein S6 kinases (S6Ks) in BeWo cells were also assessed. RT-PCR studies revealed that mTOR, 4EBP and S6Ks are expressed at mRNA level in both JEG-3 and BeWo cells. Semi-quantitative RT-PCR analysis revealed that in early stages of syncytialisation (50 µM forskolin for 48 h), the expression of mTOR and 4EBP was down-regulated when compared to unstimulated cells. In fully syncytialised cells (50 µM forskolin for 72 h) the expression of both genes was similar to basal levels. Interestingly, the phosphorylation (Ser371, Thr389) status of p70S6K remained unaltered upon forskolin treatment. These data validate BeWo cells as an experimental model to study the effects of forskolin-induced syncytialisation on mTOR signalling.This article is available through the Brunel Open Access Publishing Fun

Equivalent Lagrangians: Generalization, Transformation Maps, and Applications

Equivalent Lagrangians are used to find, via transformations, solutions and conservation laws of a given differential equation by exploiting the possible existence of an isomorphic algebra of Lie point symmetries and, more particularly, an isomorphic Noether point symmetry algebra. Applications include ordinary differential equations such as the Kummer equation and the combined gravity-inertial-Rossbywave equation and certain classes of partial differential equations related to multidimensional wave equations

Structural, Vibrational and Thermodynamic Properties of AgnCu34-n Nanoparticles

We report results of a systematic study of structural, vibrational and thermodynamical properties of 34-atom bimetallic nanoparticles from the AgnCu34-n family using model interaction potentials as derived from the embedded atom method and in the harmonic approximation of lattice dynamics. Systematic trends in the bond length and dynamical properties can be explained largely on arguments based on local coordination and elemental environment. Thus increase in the number of silver atoms in a given neighborhood introduces a monotonic increase in bond length while increase of the copper content does the reverse. Moreover, based on bond lengths of the lowest coordinated (6 and 8) copper atoms with their nearest neighbors (Cu atoms), we find that the nanoparticles divide into two groups with average bond length either close to (~ 2.58 A) or smaller (~ 2.48 A) than that in bulk copper, accompanied by characteristic features in their vibrational density of states. For the entire set of nanoparticles, vibrational modes are found above the bulk bands of copper/silver. Furthermore, a blue shift in the high frequency end with increasing number of copper atoms in the nanoparticles is traced to a shrinkage of bond lengths from bulk values. The vibrational densities of states at the low frequency end of the spectrum scale linearly with frequency as for single element nanoparticles, however, the effect is more pronounced for these nanoalloys. The Debye temperature was found to be about one third of that of the bulk for pure copper and silver nanoparticles with a non-linear increase with increasing number of copper atoms in the nanoalloys.Comment: 37 pages, 12 figure