Syntheses of urethano-, amido- and sulfonamido[60]fullerenes by nucleophilic substitutions with 1,2-(2,3-dihydro-1H-azirino)-[60]fullerene

Averdung J, Wolff C, Mattay J. Syntheses of urethano-, amido- and sulfonamido[60]fullerenes by nucleophilic substitutions with 1,2-(2,3-dihydro-1H-azirino)-[60]fullerene. Tetrahedron Letters. 1996;37(27):4683-4684.C60NH 1 and the acyl and tosyl chlorides 2 or acetic anhydride 1 in I,2-dichlorobenzene solution and pyridine give the stable fulleroaziridine derivatives 3a-d and 5 by nucleophilic substitution. Copyright (C) 1996 Elsevier Science Lt

Progress in fullerene chemistry: Exohedral functionalization of first and second generation and a new approach to aza-heterofullerenes

Mattay J, Torres-Garcia G, Averdung J, et al. Progress in fullerene chemistry: Exohedral functionalization of first and second generation and a new approach to aza-heterofullerenes. Journal of Physics and Chemistry of Solids. 1997;58(11):1929-1937.The methodology for exohedral functionalization of fullerenes and their monosubstituted derivatives is discussed (functionalization of first and second generation). Two examples ol easily accessible synthetic building blocks are presented, i.e. the cyclohexadione fused [60]fullerene and the aziridino-[60]fullerene. Both are precursors for a variety of higher functionalized fullerene derivatives with interesting properties. In addition, a new approach to azafullerenes in the gas phase is presented starting from an activated monofunctionalized [60]fullerene. (C) 1997 Elsevier Science Ltd

TGF-β1 and Smad4 overexpression induce a less invasive phenotype in highly invasive spindle carcinoma cells

We have examined the effect of transforming growth factor β1 (TGF-β1) and overexpression of the Smad4 gene on the phenotype of Car C, a ras mutated highly malignant spindle carcinoma cell line. TGF-β1-treated Car C cells overexpressing Smad4 spread with a flattened morphology with membrane ruffles abundant in vinculin and show a reduction in their invasive abilities. TGF-β1 treatment and overexpression of Smad4 also enhanced the production of PAI-1 measured by the activation of the p3TP-lux reporter gene containing a PAI-1-related promoter. This activation was abolished with a dominant-negative Smad4 construct. These results lead us to conclude that both TGF-β1 and Smad4 overexpression reduce the invasive potential of Car C cells, probably via the Smad pathway.This work was supported by Fondecyt 3000045 and post-graduate fellowship of Fundación Andes (to J.F.S.),1010703 (to J.M.) and by the Comisión Interministerial de Ciencia y Tecnología and Comunidad Autónoma de Madrid of Spain (Grants SAF98-0085-CO3-02 and 8.1/22/97,to M.Q.).Peer Reviewe

A cylindrical multiwire high-pressure gas proportional chamber surrounding a gaseous H2_{2} target with a mylar separation foil 6 mum thick

The characteristics and performances of a cylindrical multiwire proportional chamber built and used at CERN in experiment S142 for the study of the pp atom spectroscopy are presented. The chamber surrounds a high-pressure gaseous H/sub 2/ target, from which it is separated by a very thin window (6 mu m mylar foil). The active volume (90 cm long; 2 cm thick, internal diameter=30 cm) is divided into 36 equal and independent cells each covering 10 degrees in azimuth. At 4 abs. atm the detection efficiency for X-rays is higher than 20% in the whole energy range 1.5-15 keV. Typical resolutions are 35% fwhm for the 3 ke V Ar fluorescence line and 25% fwhm for the 5.5 keV /sup 54/Mn line. Working pressures from 0.5 to 16 abs. atm have been used. (8 refs)