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BACKGROUND AND PURPOSE: The clinical effects of anti-angiogenic agents remain controversial. Therefore, elucidating the pharmacological properties of these compounds is a pivotal issue. EXPERIMENTAL APPROACH: The effects of treatment with sunitinib on tumour and normal tissues of mice bearing C-26 adenocarcinoma cells were analysed by matrix-assisted laser desorption ionization MS imaging (MALDI-MSI). Expression of the key targets of sunitinib - angiogenic receptors - was studied by immunofluorescent labelling. KEY RESULTS: MALDI-MS assays showed that sunitinib and its fragment ions were present throughout tumour and normal tissues. Major metabolites were identified in blood and solid tissues, while minor drug metabolites were detectable only in blood. Tumour growth and intratumour VEGF receptor-2 expressions were significantly reduced in sunitinib-treated mice, while the expression of the other targeted receptors, PDGF receptor -á or -â and fibroblast growth factor receptor-1, remained unaffected. Within tumour tissue, the close proximity of sunitinib metabolites to the precursor ion suggested in situ metabolism of the administered drug. There were intratumour areas where the signal intensity of sunitinib correlated with expression of VEGF receptor-2. CONCLUSIONS AND IMPLICATIONS: This is the first study that demonstrates MALDI-MSI is a versatile platform to study the intratumour localization of an unlabelled anti-angiogenic drug. The combination of MALDI-MSI and immunofluorescence analysis can provide further insights into the molecular interaction of drug compounds and their targets within tumour tissue. [ABSTRACT FROM AUTHOR]

The article presents a study using measurement flight performed by a motorglider equipped with an aerosol size spectrometer and nanoparticle counter in the rural vicinity of Budapest, Hungary. The flight was spent in thermals which allow the study of how the atmospheric dynamics acts on the particle formation. The study found that hygroscopic growth affects the particle size distribution in found to be similar to ammonium sulphate particles.

Directivity is useful in the automatic monitoring of air-acoustic environmental noise because discrimination is possible not only between ground and airborne sources, but between different ground sources as wall. The experimental program compared omnidirectionals, gradients, cardioids, donuts, cardonuts, and second-order donuts as vertical discriminators between ground and airborne sources. DIFAR, DARAS, and CODAR arrays were the means examined for resolving ground sources. The data were gathered in flat, sandy, scrub-pine woods (New Jersey) and under a 50-ft jungle canopy (Panama). Nineteen different microphones were mounted at zero, 10- and 40-ft heights. Each height contained an omnidirectional, downward-looking cardioid and pair of horizontally crossed gradients. The 10-ft level included separate DIFAR, 2-ft baseline DARAS, and 75-ft CEDAR arrays. Vertical directivity discriminated between ground and airborne sources provided the microphone pattern nulled both upward and downward to attenuate the multipath. Cardonuts and second-order donuts were most effective, flyover noise being reduced 25 dB even in the presence of severe ground reflectivity. DIFAR and DARAS gave bearing angles to vehicles consistently within a few degrees in spite of the multipath. CODAR was not useful. Adaptive DIFAR enhanced capability by improving or rejecting bad bearings. [ABSTRACT FROM AUTHOR]