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Hemivannusal (6), a bicyclic sesquiterpenoid with an unprecedented skeleton, has been isolated from the marine ciliate Euplotes vannus (strain TB6). The relative configuration of 6 has been established through an extended conformational search performed by molecular mechanics and refined through ab initio quantum chemical calculations. Another strain (CM1) of the same morphospecies has been found to produce the linear prevannusadial A (7) and the monocyclic prevannusadial B (8), which could represent key intermediates for the biosynthesis both of hemivannusal (6) and of the C30 terpenoids vannusals A and B (5a and 5b), the latter pair being metabolites isolated from conspecific strains (Sil21 and

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Cutaneous melanoma is the most serious type of skin cancer, so new cytotoxic weapons against novel targets in melanoma are of great interest. Euplotin C (EC), a cytotoxic secondary metabolite of the marine ciliate Euplotes crassus, was evaluated in the present study on human cutaneous melanoma cells to explore its anti-melanoma activity and to gain more insight into its mechanism of action. EC exerted a marked cytotoxic effect against three different human melanoma cell lines (A375, 501Mel and MeWo) with a potency about 30-fold higher than that observed in non-cancer cells (HDFa cells). A pro-apoptotic activity and a decrease in melanoma cell migration by EC were also observed. At the molecular level, the inhibition of the Erk and Akt pathways, which control many aspects of melanoma aggressiveness, was shown. EC cytotoxicity was antagonized by dantrolene, a ryanodine receptor (RyR) antagonist, in a concentration-dependent manner. A role of RyR as a direct target of EC was also suggested by molecular modelling studies. In conclusion, our data provide the first evidence of the anti-melanoma activity of EC, suggesting it may be a promising new scaffold for the development of selective activators of RyR to be used for the treatment of melanoma and other cancer types.

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Terpenes U 0200Hemivannusal and Prevannusadials -New Sesquiterpenoids from the Marine Ciliate Protist Euplotes vannus: The Putative Biogenetic Precursors of Dimeric Terpenoid Vannusals. -Hemivannusal (I) and prevannusadials A (II) and B (III) are isolated and structurally characterized. The latter represent key intermediates for the synthesis of (I) and of the C-30 terpenoids, isolated from the same morphospecies. -(GUELLA*, G.; CALLONE, E.; DI GIUSEPPE, G.; FRASSANITO, R.; FRONTINI, F. P.; MANCINI, I.; DINI, F.; Eur. J. Org. Chem. 2007, 31, 5226-5234; Lab. Chim. Bioorg., Univ. Trento, I-38050 Povo-Trento, Italy; Eng.) -Y. Steudel 08-184

handheld, and in field-portable, enabling a spatiotemporal mapping of the microbiome potentially leading to unprecedented insight into human health and environment conditions. [1] Smartphone-based optical/fluorescence microscopy leverage the scaling down of lens/filter optical components and the computational/networking capabilities of smartphones. [1][2][3][4] These platforms have proved to be very effective for biomedical applications. Nonethless, the cost of manufacturing of miniaturized optical components, i.e., the lenses and filters, for the assembling of add-on optical modules for smartphones with reduced size and weight (yet, hundreds of grams and of cm 3 ) has hampered the diffusion of smartphone-based microscopy to date. [5] To circumvent these limitations researchers have developed strategies to fabricate polymeric (e.g., polydimethylsiloxane, PDMS) magnifying lenses that can be directly attached to the smartphone camera to boost intrinsic magnification and resolution performance. [6][7][8] These strategies include hanging droplet of uncured PDMS deposited by inkjet printing on heated flat surface; [6] moldless thermal curing of PDMS droplet prepared using a moving needle extruder; [7] drop-casting of uncured PDMS droplet onto a smooth circular disk of poly(methyl methacrylate); [8] moldless printing of uncured PDMS droplet using nanostructured porous silicon (PSi) as templating layer. [5] In two cases the polymeric lens also embedded a rejection optical filter that enabled performing smartphone-based fluorescence microscopy leveraging image magnification and light rejection properties of the lens. [5,9] In Ref. [9], the lens-filter element was prepared mixing PDMS prepolymer with dyes featuring high absorbance in specific wavelength regions. The lens was coupled to a smartphone and used in several bioanalytic applications, namely, cell and tissue observation, cell counting, and plasmid transfection evaluation. [9] In Ref.[5], a nanostructured porous silicon oxide (PSiO 2 ) filter, namely, a distributed Bragg reflector (DBR) with stopband tuned to reject light in a selected wavelength region, was integrated into the PDMS lens. The lens-filter element was coupled to a smartphone and used for the fluorescence imaging and counting of CAOV-3 ovarian cancer cells in a conventional live/dead assay. [5] Very recently our research group developed a fluorideassisted chemical route for the in-situ synthesis of metal nanoparticles (NPs) on PDMS. [10] In contrast to conventional in Here the 4D printing of a magnifying polydimethylsiloxane (PDMS) lens encoded with a tunable plasmonic rejection filter is reported. The lens is formed by moldless printing of PDMS pre-polymer on a nanostructured porous silicon (PSi) templating layer. A nanometer-thick plasmonic filter is integrated on the lens surface by in situ synthesis of Ag and Au nanoparticles (NPs) with programmed density. The filter can be designed to reject light at the plasmonic resonance wavelength of the NPs with an optical density tunable from 0 to 3 and re...