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Although nuclear magnetic resonance (NMR) can provide a wealth of information, it often suffers from a lack of sensitivity. Dynamic Nuclear Polarization (DNP) provides a way to increase the polarization and hence the signal intensities in NMR spectra by transferring the favourable electron spin polarization of paramagnetic centres to the surrounding nuclear spins through appropriate microwave irradiation. In our group at EPFL, two complementary DNP techniques are under investigation: the combination of DNP with magic angle spinning at temperatures near 100 K ('MAS-DNP'), and the combination of DNP at 1.2 K with rapid heating followed by the transfer of the sample to a high-resolution magnet ('dissolution DNP'). Recent applications of MAS-DNP to surfaces, as well as new developments of magnetization transfer of 1H to 13C at 1.2 K prior to dissolution will illustrate the work performed in our group. A second part of the paper will give an overview of some 'non-enhanced' activities of our laboratory in liquid- and solid-state NMR.

Of the numerous morphological variants of meningiomas only few, and among these the rhabdoid meningioma, have prognostic importance. Rhabdoid meningiomas were described for the first time in 1998 as an unusual variant with increased proliferative activity. In 2000 they have been included in the revised WHO classification of tumours of the CNS as a subtype of meningiomas with increased risk of recurrence and more aggressive growth, corresponding to WHO grade III. We report the case of a rhabdoid meningioma in a 21-year-old woman presenting as a intracerebral tumour mimicking an oligodendroglioma. The tumour showed features of a meningioma and a rhabdoid morphology with angiomatous components and was considered to be a rhabdoid meningioma. After surgery a small residual tumour remained. The patient received postoperative radiotherapy resulting in regression of the residual tumour in control examinations after 4 and 8 months. Using the presented case we discuss the differential diagnosis and prognostic significance of recognition of a rhabdoid meningioma.

The analysis of thymic epithelial tumors (TET) with and without myasthenia gravis (MG) has identified both a residual organotypic differentiation of TETs and the aberrant expression of acetylcholine receptor (AChR)-epitopes in TET epithelial cells to be associated with MG. These findings have suggested an abnormal selection of helper T cells as a mechanism of paraneoplastic MG. Here we show by electronmicroscopy that epithelial cells of TETs and normal thymus exhibit the morphological features (autophagic vacuoles) thought to be necessary to process endogenous proteins for presentation by MHC class II molecules to immature T cells.

This is a research on the pulmonary normal maturity of a Wistar's Rat from the biochemic and morphological point of view. To do that we have chosen 3 lots of 5 rats each. The animals were sacrificed by killing them up to 15, 18 and 21 days of pregnancy. Then we have removed the amniotic liquid of each rat to know or study the creatinin concentration and the lecithin/sphingomyelin relation or report. To every foetus that we have got from every rat we have removed or extirpated the lungs to do a study under the optic microscope by using the hematoxilin-eosin together with the Fontana-Masson techniques.

This is a research on the pulmonary normal and pathological (Diabetes) maturity of the WISTAR's Rat. To do that we have chosen 6 lots of rats. The animals were sacrificed by killing them up to 15., 18. and 21. days of pregnancy, then we removed the amniotic liquid from each rat to know or find out the lecithin/sphingomyelin and creatinin relations or reports.

This is a research on the pulmonary normal and pathological (Diabetes) of a Wistar's rat from a morphological point of view doing a comparative study with biochimic data or results. To do this we have sacrified by killing the different animals up to 15, 18 and 21 days of pregnancy and then we have removed or extripated the foetus lungs to do a study under the optic microscope by using the Hematoxilin-eosin together with the Fontana-Masson-techniques.