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Two molecular baskets 16-, each with three (S)-glutamic acids at its rim, were found (NMR, ITC) to complex diammonium alkanes 22+-52+ (+H3N(CH2)nNH3+, n = 7-10) giving ternary [2-5⊂12]10- assemblies (K = 107-109 M-2). From the magnetic perturbation of proton nuclei (1H NMR, NICS), we deduced that each guest assumed a U shape within the binary complex, [2-5⊂1]4-. Two ammonium groups were bound in the "anionic nest" at the top of 16-, while the hydrocarbon chain resided in its nonpolar cavity. From detailed ITC analyses, we showed that the binary complex [2-5⊂1]4- forms first and then another 16- capped [2-5⊂1]4- to give [2-5⊂12]10-, via interactions of the carboxylates at the rims with ammoniums on the guest. Long-range NOEs revealed that U-shaped 22+ and 52+ coiled into highly strained twist-turn-twist formations, for the first time observed within an abiotic host while curiously resembling helix-turn-helix motif found in DNA binding proteins.

A series of 1,3-substituted 8-styrylxanthines (11a-d) was synthesized, under chemo- and regioselective conditions, in a good overall yield. The compounds showed affinity towards both A1 and A2A-adenosine receptors by radioligand binding by means of in vitro assays. The (E)-3-ethyl-1-propyl-8-styrylxanthine (11a) showed the greatest affinity towards the A2A receptor, whereas (E)-3-pentyl-1-propyl-8-styrylxanthine (11d) showed the greatest affinity for the A1 receptor. When the 8-styrylxanthines 11a (A15Et) and 11c (A15Bu) were administrated in rats, which were previously injured with 6-hydroxydopamine at the substantia nigra pars compacta (SNc), the turning behavior decreased 50%. Based on these results we propose to A15Et as a potential compound to treat some symptoms of Parkinson’s disease.

One-third of top-selling drugs are derived from natural products. When only a fraction of the bioactive natural products diversity has been explored, huge opportunities still remain for discovering novel leads for the development of new drugs. Clear cell renal cell carcinoma (ccRCC) is a highly vascular tumour arising from epithelial elements. Mutations in the Von Hippel-Lindau (VHL) gene are responsible for VHL disease and arise in the majority of Renal Cell Carcinoma (RCC) as well as in other types of cancer. Renal carcinoma cell lines with naturally occurring VHL mutations (RCC4 VA) and their genetically matched wild-type VHL (RCC4 VHL) counterparts were seeded onto 96-well plates and allowed to attach overnight. Fungal extracts were tested on both cell lines. Clinically useful antitumor agents were used as positive controls and as reference points to establish the efficacy and selectivity of the new compounds. Renal cell carcinoma cell lines expressing VHL or not were treated with Carboxyfluorescein succinimidyl ester (CFSE). The day after cell inoculation, extracts were added and during the following days of incubation, fluorescence intensity was measured as a surrogate marker for cell viability. The most promising extracts selectively inhibited growth of pVHL-defi- cient cells but not of wild-type VHL cells. We used High Content Bio-imaging, a complete cellular imaging workflow that integrates instruments and software to acquire and analyze images, to evaluate their effect. Cell imaging can reveal effects that would be overlooked by other cell assay approaches. This target-based whole cell screen is a new strategy, which ensures cell permeability and target selectivity especially in natural product screening where natural product purification is a labour of extensive work. This approach permitted a dynamic study where fluorescence was measured without affecting cell viability and enabling a better detection of cytotoxic effects such as autophagy, senescence or late apoptosis.

From the beginning of the 16 th until the end of the 19 th century the most widely used mirrors consisted of a pane of glass backed with a reflecting layer of tin-mercury amalgam. They were made by sliding the glass pane over a tin foil covered with liquid mercury. After removal of the superfluous mercury, tin amalgam formed slowly at ambient temperature and yielded a reflecting layer adhering to the surface of the glass. Such mirrors often deteriorate in the course of time by oxidation of the tin in the amalgam to stannous or stannic oxide. 119Sn Mossbauer spectroscopy, scanning electron microscopy, micro-XRF and X-ray diffraction have been used to study this deterioration process. The studied specimens were a modern mirror made for the reconstruction of the Green Vault in Dresden in the early 2000s, two rather well preserved German mirrors from the 17 th and 19 th centuries and several strongly deteriorated specimens of Baroque mirrors from the south of Spain. The modern mirror consists mainly of a Sn0.9Hg0.1 amalgam with only 2 % of SnO2. The older German mirrors showed more pronounced oxidation, containing 12 and 15 % of SnO2, which did not noticeably impair their reflectivity. In the samples from the Spanish mirrors at best a few percent of metallic phase was left. The majority of the tin had oxidised to SnO2, but between 8 and 20 % of the tin was present as SnO. X-ray diffraction yielded similar results and micro-XRF mapping using synchrotron radiation for excitation gave information on the distribution of Sn and Hg in the reflecting layer of the mirrors.

Natural products are considered an extremely valuable source for the discovery of new drugs against diverse pathologies. As yet, we have only explored a fraction of the diversity of bioactive compounds, and opportunities for discovering new natural products leading to new drugs are huge. In the present study, U2nesRELOC, a previously established cell-based imaging assay, was employed to screen a collection of extracts of microbial origin for nuclear export inhibition activity. The fluorescent signal of untreated U2nesRELOC cells localizes predominantly to the cytoplasm. Upon treatment with the nuclear export inhibitor leptomycin B, the fluorescent-tagged reporter proteins appear as speckles in the nucleus. A proprietary collection of extracts from fungi, actinomycetes, and unicellular bacteria that covers an uncommonly broad chemical space was used to interrogate this nuclear export assay system. A two-step image-based analysis allowed us to identify 12 extracts with biological activities that are not associated with previously known active metabolites. The fractionation and structural elucidation of active compounds revealed several chemical structures with nuclear export inhibition activity. Here we show that substrates of the nuclear export receptor CRM1, such as Rev, FOXO3a and NF-B, accumulate in the nucleus in the presence of the fungal metabolite MDN-0105 with an IC50 value of 3.4 mu M. Many important processes in tumor formation and progression, as well as in many viral infections, critically depend on the nucleocytoplasmic trafficking of proteins and RNA molecules. Therefore, the disruption of nuclear export is emerging as a novel therapeutic approach with enormous clinical potential. Our work highlights the potential of applying high-throughput phenotypic imaging on natural product extracts to identify novel nuclear export inhibitors. Fundacion MEDINA; MICINN [PCT-010000-2010-3] info:eu-repo/semantics/publishedVersion

We have carried out, in a tight—binding treatment, a. study of the surface core level shifts for some semiconductor compounds. We analyse the ideal and the reconstructed (110) semiconductor surfaces under a local charge neutrality condition and with a selfconsistent treatment. Our results show how the surface reconstruction and the selfconsistent treatment modify the calculated surface core level shifts and give a reasonable agreement with the experimental results.

1. 1. We studied the hematology and blood chemistry of young Great Bustards (Otis tarda). 2. 2. Red cell numbers (2,460,000 cell/mm3), hemoglobin content (11.7g/100ml) and hematocrit (41%) are smaller than in previously studied captive adults, whereas leukocytes numbers (11,000 cell/mm3) are lower. 3. 3. Heterophils (38%) and lymphocytes (47%) are in similar proportions. Eosinophils are also abundant (14%), the other white cell types being more scarce (basophils 2%, monocytes 4%). 4. 4. Plasma uric acid level (22mg/100ml) is higher than urea level (17mg/100ml). Cholesterol and triglycerides plasma concentrations are 132 and 83mg/100ml, respectively. 5. 5. Plasma protein levels (3.6g/100ml) are similar to that previously found in adult captive animals.