Coastal meroplanktonic larval stages of peninsula de Llevant natural reserve determined with light traps

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Isotopic tissue fractionation in captive and wild lobsters Palinurus elephas (Fabricius, 1787)

Isotopic fractionation δ13C and for δ15N of the spiny lobster Palinurus elephas has been tested in four tissues: tail and leg muscle, telson and hemolymph. Comparison of tissue fractionation factors among tissues in two groups of lobsters, captive (controlled diet) and wild, show lower intra-individual variability in captive than in wild individuals. Statistical analysis (PERMANOVA) was performed to check for significant differences in δ13C and δ15N isotopic signatures between tissues and treatments. Results show significant differences in the δ13C and δ15N isotopic composition among the four tissues analyzed. Legs are the most enriched tissue in δ15N, followed by muscle, hemolymph and telson in both captive and wild specimens. For δ13C the sequence is muscle > legs> hemolymph ~ telson. The fractionation or enrichment factor for δ 13C is 0.87‰ and 1.17‰ and for δ15N 1.99‰ and 2.38‰, in captive and wild lobsters respectively. Leg muscle presents the lowest variability at isotopic level for N and telson for C. Telson presents differences for N and C in both captive and wild lobsters (Mann-U Whitney p<0.05). Hemolymph and leg only present statistical differences for N between captive and wild individuals. In the first study of tissue isotopic fractioning of a spiny lobster species we conclude that leg muscle is the best tissue for studying P. elephas trophic dynamics applying non-invasive technique

Integrated Multitrophic Aquaculture: Filter feeders bivalves as efficient reducers of wastes derived from coastal aquaculture assessed with stable isotope analyses

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Conjugation of a Ru(II) Arene Complex to Neomycin or to Guanidinoneomycin Leads to Compounds with Differential Cytotoxicities and Accumulation between Cancer and Normal Cells

A straightforward methodology for the synthesis of conjugates between a cytotoxic organometallic ruthenium(II) complex and amino- and guanidinoglycosides, as potential RNA-targeted anticancer compounds, is described. Under microwave irradiation, the imidazole ligand incorporated on the aminoglycoside moiety (neamine or neomycin) was found to replace one triphenylphosphine ligand from the ruthenium precursor [(η6-p-cym)RuCl(PPh3)2]+, allowing the assembly of the target conjugates. The guanidinylated analogue was easily prepared from the neomycin-ruthenium conjugate by reaction with N,N′-di-Boc-N″-triflylguanidine, a powerful guanidinylating reagent that was compatible with the integrity of the metal complex. All conjugates were purified by semipreparative high-performance liquid chromatography (HPLC) and characterized by electrospray ionization (ESI) and matrix-assisted laser desorption-ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) and NMR spectroscopy. The cytotoxicity of the compounds was tested in MCF-7 (breast) and DU-145 (prostate) human cancer cells, as well as in the normal HEK293 (Human Embryonic Kidney) cell line, revealing a dependence on the nature of the glycoside moiety and the type of cell (cancer or healthy). Indeed, the neomycin-ruthenium conjugate (2) displayed moderate antiproliferative activity in both cancer cell lines (IC50 ≈ 80 μM), whereas the neamine conjugate (4) was inactive (IC50 ≈ 200 μM). However, the guanidinylated analogue of the neomycin-ruthenium conjugate (3) required much lower concentrations than the parent conjugate for equal effect (IC50 = 7.17 μM in DU-145 and IC50 = 11.33 μM in MCF-7). Although the same ranking in antiproliferative activity was found in the nontumorigenic cell line (3 2 > 4), IC50 values indicate that aminoglycoside-containing conjugates are about 2-fold more cytotoxic in normal cells (e.g., IC50 = 49.4 μM for 2) than in cancer cells, whereas an opposite tendency was found with the guanidinylated conjugate, since its cytotoxicity in the normal cell line (IC50 = 12.75 μM for 3) was similar or even lower than that found in MCF-7 and DU-145 cancer cell lines, respectively. Cell uptake studies performed by ICP-MS with conjugates 2 and 3 revealed that guanidinylation of the neomycin moiety had a positive effect on accumulation (about 3-fold higher in DU-145 and 4-fold higher in HEK293), which correlates well with the higher antiproliferative activity of 3. Interestingly, despite the slightly higher accumulation in the normal cell than in the cancer cell line (about 1.4-fold), guanidinoneomycin-ruthenium conjugate (3) was more cytotoxic to cancer cells (about 1.8-fold), whereas the opposite tendency applied for neomycin-ruthenium conjugate (2). Such differences in cytotoxic activity and cellular accumulation between cancer and normal cells open the way to the creation of more selective, less toxic anticancer metallodrugs by conjugating cytotoxic metal-based complexes such as ruthenium(II) arene derivatives to guanidinoglycosides

Assessing Bathymetric Distribution of Meroplankton Communities in Shallow Waters Using Light Traps

Small- scale distribution patterns of larval distribution were studied at a very nearshore meroplanktonic community during the months of June and August 2009 in two Mediterranean marine protected areas (MPAs), Cala Ratjada and Columbretes Islands, using light traps. A total of 129,255 epibenthic and meroplanktonic organisms belonging to 39 taxa were collected. Peracarida crustaceans were the most abundant taxa, followed by larval decapods, especially brachyuran, with Monodaeus couchii, Pinnotheres sp., Ebalia sp. and specimens from Portunidae family as the most abundant species. In Cala Ratjada, a clear vertical pattern on species distribution was found, with lower abundance at near-surface traps and higher at near-bottom traps. The horizontal distribution was also tested, with higher captures in nearshore stations, decreasing as moving offshore. A vertical pattern was also found in Columbretes Islands, although results did not show clear significant differences. In both marine reserves, the community composition was similar, with the exception of larval decapods, with a higher proportion of zoea larval stages in Columbretes Islands. Finally, light traps have been corroborated as a valuable therefore to asses crustacean distribution and possible effects of protection on planktonic stage

Genetics and stable isotopes reveal non-obvious population structure of bottlenose dolphins (Tursiops truncatus) around the Balearic Islands

The effective management of wildlife requires that populations are defined in a biological sensible manner. We investigated the population structure of bottlenose dolphins (Tursiops truncatus) in waters around the Balearic archipelago using two complementary techniques; DNA markers (i.e. microsatellites and a portion of the mitochondrial control region) and stable isotopes (δ13C, δ15N). We used tissue samples from biopsies (n = 50) and fresh carcasses (n = 7) obtained around the islands of Gimnèsies and Pitiüses, and Comunitat Valenciana (Western Mediterranean Sea). Genetic differentiation between individuals from Gimnésies and Pitiüses and between individuals from across these two areas and individuals from Comunitat Valenciana was significant when assessing FST, but no substructure was found using clustering methods (i.e. DAPC and Bayesian clustering). δ13C and δ15N profiles were not significantly different between dolphins from Gimnésies and Pitiüses. Dolphins from both areas showed coastal carbon isotopic values and similar trophic niche levels. However, the trophic niche of dolphins from Gimnésies was broader than the trophic niche of Pitiüses’ dolphins. These results indicate non-obvious population structure between the mainland and the archipelago, or between islands within the archipelago. The use of combined techniques, which integrate information over different time scales, is applicable to other species and areas