2,186 research outputs found

    Spotlight on islands.On the origin and diversification of an ancient lineage of the Italian wall lizard Podarcis siculus in the western Pontine Islands

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    Groups of proximate continental islands may conceal more tangled phylogeographic patterns than oceanic archipelagos as a consequence of repeated sea level changes, which allow populations to experience gene flow during periods of low sea level stands and isolation by vicariant mechanisms during periods of high sea level stands. Here, we describe for the first time an ancient and diverging lineage of the Italian wall lizard Podarcis siculus from the western Pontine Islands. We used nuclear and mitochondrial DNA sequences of 156 individuals with the aim of unraveling their phylogenetic position, while microsatellite loci were used to test several a priori insular biogeographic models of migration with empirical data. Our results suggest that the western Pontine populations colonized the islands early during their Pliocene volcanic formation, while populations from the eastern Pontine Islands seem to have been introduced recently. The inter-island genetic makeup indicates an important role of historical migration, probably due to glacial land bridges connecting islands followed by a recent vicariant mechanism of isolation. Moreover, the most supported migration model predicted higher gene flow among islands which are geographically arranged in parallel. Considering the threatened status of small insular endemic populations, we suggest this new evolutionarily independent unit be given priority in conservation efforts

    Novel 1,3-thiazolidin-4-one derivatives as promising anti-Candida agents endowed with anti-oxidant and chelating properties

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    Pursuing our recent outcomes regarding the antifungal activity of N-substituted 1,3-thiazolidin-4-ones, we synthesized thirty-six new derivatives introducing aliphatic, cycloaliphatic and heteroaromatic moieties at N1-hydrazine connected with C2 position of the thiazolidinone nucleus and functionalizing the lactam nitrogen with differently substituted (NO2, NH2, Cl and F) benzyl groups. These compounds were tested to evaluate their minimum inhibitory concentration (MIC) against several clinical Candida spp. with respect to topical and systemic reference drugs (clotrimazole, fluconazole, ketoconazole, mi- conazole, tioconazole, amphotericin B). Moreover, anti-oxidant properties were also evaluated by using different protocols including free radical scavenging (DPPH and ABTS), reducing power (CUPRAC and FRAP), metal chelating and phosphomolybdenum assays. Moreover, for the most active derivatives we assessed the toxicity (CC50) against Hep2 human cells in order to characterize them as multi-target agents for fungal infections

    Monitoraggio degli APC negli EPR Cosa, come e perchè

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    Linee guida per il monitoraggio APC negli EP

    Towards an optimal design for ecosystem-level ocean observatories

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    Four operational factors, together with high development cost, currently limit the use of ocean observatories in ecological and fisheries applications: 1) limited spatial coverage; 2) limited integration of multiple types of technologies; 3) limitations in the experimental design for in situ studies; and 4) potential unpredicted bias in monitoring outcomes due to the infrastructure’s presence and functioning footprint. To address these limitations, we propose a novel concept of a standardized “ecosystem observatory module” structure composed of a central node and three tethered satellite pods together with permanent mobile platforms. The module would be designed with a rigid spatial configuration to optimize overlap among multiple observation technologies each providing 360° coverage around the module, including permanent stereo-video cameras, acoustic imaging sonar cameras, horizontal multi-beam echosounders and a passive acoustic array. The incorporation of multiple integrated observation technologies would enable unprecedented quantification of macrofaunal composition, abundance and density surrounding the module, as well as the ability to track the movements of individual fishes and macroinvertebrates. Such a standardized modular design would allow for the hierarchical spatial connection of observatory modules into local module clusters and larger geographic module networks, providing synoptic data within and across linked ecosystems suitable for fisheries and ecosystem level monitoring on multiple scales.Peer ReviewedPostprint (author's final draft

    Biogenic sediments from coastal ecosystems to beach-dune systems: implications for the adaptation of mixed and carbonate beaches to future sea level rise

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    Coastal ecosystems produce and store carbonate particles, which play a significant role in the carbonate dynamics of coastal areas and may contribute to the sediment budget of adjacent beaches. In the nearshore seabed of temperate zones (e.g. Mediterranean Sea and South Australia), marine biogenic carbonates are mainly produced inside sea-grass meadows. This study quantifies the contribution of biogenic sediments, mainly produced in Posidonia oceanica seagrass meadows and secondarily in photophilic algal communities, to the sediment budget of a Mediterranean beach-dune system (San Giovanni beach, western Sardinia, western Mediterranean Sea). A set of geophysical, petrographic and sedimentological data was used to estimate the sediment volume and composition of the beach-dune system as a whole. The San Giovanni beach-dune system contains 3797000 +/- 404000 t of sediment, 83% (3137000 +/- 404000 t) of which is located in the coastal wedge, 16% (619000 +/- 88000 t) in the dune fields and 1% (41000 +/- 15000 t) in the sub-aerial beach. The sediments are composed of mixed modern bioclastic and relict bioclastic and non-bioclastic grains from various sources. The system receives a large input of modern bioclastic grains, mainly composed of rhodophytes, molluscs and bryozoans, which derive from sediment production of present-day carbonate factories, particularly P. oceanica seagrass meadows. Radiocarbon dating of modern bioclastic grains indicated that they were produced during the last 4.37 kyr. This value was used to estimate the longterm deposition rates of modern bioclastic sediments in the various beach compartments. The total deposition rate of modern bioclastic grains is 46000 +/- 5000 t century 1, mainly deposited in the coastal wedge (39000 +/- 4000 t century(-1)) and dunes (7000 +/- 1000 t century(-1)), and 46 000 t represents similar to 1.2% of the total beach-dune sediment mass. Carbonate production from coastal ecosystems was estimated to be 132000/307000 t century(-1), 28% (15%/34 %) of which is transported to the beach-dune system, thus significantly contributing to the beach sediment budget.The contribution to the beach sediment budget represents a further ecosystem service, which our data can help quantify, provided by P. oceanica. The value of this sediment-supply service is in addition to the other important ecological services provided by seagrass meadows. The dependence of the beach sediment budget on carbonate production associated with coastal ecosystems has several implications for the adaptation of mixed and carbonate beaches to the loss of seagrass meadows due to local impacts and the changes expected to occur over the next few decades in coastal ecosystems following sea level rise

    Chapter 2 Towards an Optimal Design for Ecosystem-Level Ocean Observatories

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    Four operational factors, together with high development cost, currently limit the use of ocean observatories in ecological and fisheries applications: 1) limited spatial coverage; 2) limited integration of multiple types of technologies; 3) limitations in the experimental design for in situ studies; and 4) potential unpredicted bias in monitoring outcomes due to the infrastructure’s presence and functioning footprint. To address these limitations, we propose a novel concept of a standardized “ecosystem observatory module” structure composed of a central node and three tethered satellite pods together with permanent mobile platforms. The module would be designed with a rigid spatial configuration to optimize overlap among multiple observation technologies each providing 360° coverage of a cylindrical or hemi-spherical volume around the module, including permanent stereo-video cameras, acoustic imaging sonar cameras, horizontal multi-beam echosounders and a passive acoustic array. The incorporation of multiple integrated observation technologies would enable unprecedented quantification of macrofaunal composition, abundance and density surrounding the module, as well as the ability to track the movements of individual fishes and macroinvertebrates. Such a standardized modular design would allow for the hierarchical spatial connection of observatory modules into local module clusters and larger geographic module networks, providing synoptic data within and across linked ecosystems suitable for fisheries and ecosystem level monitoring on multiple scales

    The AOM/DSS murine model for the study of colon carcinogenesis: From pathways to diagnosis and therapy studies

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    Colorectal cancer (CRC) is a major health problem in industrialized countries. Although inflammation-linked carcinogenesis is a well accepted concept and is often observed within the gastrointestinal tract, the underlying mechanisms remain to be elucidated. Inflammation can indeed provide initiating and promoting stimuli and mediators, generating a tumour-prone microenvironment. Many murine models of sporadic and inflammation-related colon carcinogenesis have been developed in the last decade, including chemically induced CRC models, genetically engineered mouse models, and xenoplants. Among the chemically induced CRC models, the combination of a single hit of azoxymethane (AOM) with 1 week exposure to the inflammatory agent dextran sodium sulphate (DSS) in rodents has proven to dramatically shorten the latency time for induction of CRC and to rapidly recapitulate the aberrant crypt foci-adenoma-carcinoma sequence that occurs in human CRC. Because of its high reproducibility and potency, as well as the simple and affordable mode of application, the AOM/DSS has become an outstanding model for studying colon carcinogenesis and a powerful platform for chemopreventive intervention studies. In this article we highlight the histopathological and molecular features and describe the principal genetic and epigenetic alterations and inflammatory pathways involved in carcinogenesis in AOM/DSS-treated mice; we also present a general overview of recent experimental applications and preclinical testing of novel therapeutics in the AOM/DSS model
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