542 research outputs found

    Bisabolane type sesquiterpenes from a marine Didiscus sponge

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    Two bisabolane type sesquiterpene phenols, (+)-curcuphenol (1) and (+)-curcudiol (2), were isolated from a Philippine marine sponge, Didiscus sp., in addition to b -sitosterol (3) and phenethylamine (4). The structures of the metabolites were established on the basis of spectral evidence (1D- and 2D NMR, [a]D, EIMS). (+)-Curcuphenol (1) showed cytotoxicity, which is indicative of a p53 independent mechanism

    Cytotoxic bromoindole derivatives and terpenes from the Philippine marine sponge Smenospongia sp.

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    A detailed chemical analysis of a Philippine marine sponge Smenospongia sp. has been performed. This study yielded four new metabolites, 5-bromo-l-tryptophan (1), 5-bromoabrine (2), 5,6-dibromoabrine (3) and 5-bromoindole-3-acetic acid (4). The pyrroloiminoquinone alkaloid, makaluvamine O (5) as well as 5,6-dibromotryptamine (6), aureol (7) and furospinulosin 1 (8) were also isolated. Although 1 and 4 have been synthesized previously, this is the first report on the isolation of these compounds from a natural source. The furanosesterterpene furospinulosin 1 (8) was obtained for the first time from the genus Smenospongia. The structures of all compounds were established by spectroscopic methods (UV, IR, 1D and 2D NMR, MS, [ι]D). The cytotoxic potential of 1Ð8 was evaluated in a panel of isogenic HCT-116 human colon tumor cell lines

    Parametric and Optimization Studies on the entrapment of Potassium Fertilizer into Chitosan-Poly(methacrylic acid) Carrier via Ionic Gelation

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    Nanofertilizer is an emerging technology for exhibiting slow release mechanism of fertilizer application. This slow release mechanism allows increase in nutrient uptake of plants while minimizing environmental pollution; specifically, reducing eutrophication in bodies of water. This study includes parametric and optimization studies for ionic gelation process in the formulation of potassium fertilizer in chitosan polymethacrylic acid (CS-PMAA) carrier, and subsequent characterization of the formulated K fertilizer. A 2k factorial experimnental design was initially implemented to determine significant factors. Results show that polymerization time inversely affects the K content concentration of the K-CS-PMAA fertilizer due to the swelling behavior of chitosan, while K:CS-PMAA ratio directly affects the K content concentration. Upon numerical optimization, the conditions found to maximize K content of the formulated fertilizer are 3000 ppm K+ corresponding to 1.5:1 ratio of the K loading concentration to CS-PMAA carrier for 30 mins polymerization time. The optimum K content of K-CS-PMAA fertilizer is about 34.98% w/w – less than the 44.27% w/w K content of the fertilizer grade, muriate of potash (MOP). The Dynamic Light Scattering (DLS) and Scanning Electron Microscope (SEM) results of 368.1 nm and 75.4 nm, respectively, indicated that K-CS-PMAA is nanosized. The Fourier Transform Infrared Spectroscopy (FT-IR) results proved the presence of CS-PMAA with deviations at 1483.01 and 1405.07 caused by the vibration in the --COO-anion groups of PMAA indicating the attachment of potassium in the nanoparticle. Furthermore, the fertilizer formulated was proved to exhibit slow release behavior with the value of 83.70% K+ release after 48 hours compared to the 99.43% release of MOP

    Shipworm bioerosion of lithic substrates in a freshwater setting, Abatan River, Philippines: ichnologic, paleoenvironmental and biogeomorphical implications

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    Teredinid bivalves, commonly referred to as shipworms, are known for their propensity to inhabit, bioerode, and digest woody substrates across a range of brackish and fully marine settings. Shipworm body fossils and/or their borings, which are most allied with the ichnotaxon Teredolites longissimus, are found in wood preserved in sedimentary sequences ranging in age from Early Cretaceous to Recent and traditionally they have been regarded as evidence of marginal marine or marine depositional environments. Recent studies associated with the Philippine Mollusk Symbiont International Collaboration Biodiversity Group (PMS-ICBG) expedition on the island of Bohol, Philippines, have identified a new shipworm taxon (Lithoredo abatanica) that is responsible for macrobioerosion of a moderately indurated Neogene foraminiferal packstone cropping out along a freshwater reach of the Abatan River. In the process of drilling into and ingesting the limestone, these shipworms produce elongate borings that expand in diameter very gradually toward distal termini, exhibit sinuous or highly contorted axes and circular transverse outlines, and are lined along most of their length by a calcite tube. Given their strong resemblance to T. longissimus produced in wood but their unusual occurrence in a lithic substrate, these shipworm borings can be regarded as incipient Gastrochaenolites or, alternatively, as Apectoichnus. The alternate names reflect that the borings provide a testbed for ideas of the appropriateness of substrate as an ichnotaxobasis. The discovery of previously unrecognized shipworm borings in lithic substrates and the co-occurrence of another shipworm (Nausitora) in submerged logs in the same freshwater setting have implications for interpreting depositional conditions based on fossil teredinids or their ichnofossils. Of equal significance, the Abatan River study demonstrates that macrobioerosion in freshwater systems may be just as important as it is in marine systems with regard to habitat creation and landscape development. L. abatanica serve as ecosystems engineers in the sense that networks of their abandoned borings provide habitats for a variety of nestling invertebrates, and associated bioerosion undoubtedly enhances rates of mechanical and chemical degradation, thus influencing the Abatan River profile

    Tamilokus mabinia, a new, anatomically divergent genus and species of wood-boring bivalve from the Philippines

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    Here we describe an anatomically divergent wood-boring bivalve belonging to the family Teredinidae. Specimens were collected off the coast of Mabini, Batangas, Philippines, in February 2018, from sunken driftwood at a depth of less than 2 m. A combination of characteristics differentiates these specimens from members of previously named teredinid genera and species. Most notable among these include: an enlarged cephalic hood which extends across the posterior slope of the shell valves and integrates into the posterior adductor muscle; a unique structure, which we term the ‘cephalic collar’, formed by protruding folds of the mantle immediately ventral to the foot and extending past the posterior margin of the valves; a large globular stomach located entirely posterior to the posterior adductor muscle and extending substantially beyond the posterior gape of the valves; an elongate crystalline style and style sac extending from the base of the foot, past the posterior adductor muscle, to the posteriorly located stomach; calcareous pallets distinct from those of described genera; a prominently flared mantle collar which extends midway along the stalk of the pallets; and, separated siphons that bear a pigmented pinstripe pattern with highly elaborate compound papillae on the incurrent siphon aperture. We used Micro-Computed Tomography (Micro-CT) to build a virtual 3D anatomical model of this organism, confirming the spatial arrangement of the structures described above. Phylogenetic analysis of the small (18S) and large (28S) nuclear rRNA gene sequences, place this bivalve within the Teredindae on a branch well differentiated from previously named genera and species. We propose the new genus and species Tamilokus mabinia to accommodate these organisms, raising the total number of genera in this economically and environmentally important family to 17. This study demonstrates the efficacy of Micro-CT for anatomical description of a systematically challenging group of bivalves whose highly derived body plans are differentiated predominantly by soft tissue adaptations rather than features of calcareous hard-parts

    Serous cystic neoplasm of the pancreas: A multinational study of 2622 patients under the auspices of the International Association of Pancreatology and European Pancreatic Club (European Study Group on Cystic Tumors of the Pancreas)

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    OBJECTIVES: Serous cystic neoplasm (SCN) is a cystic neoplasm of the pancreas whose natural history is poorly known. The purpose of the study was to attempt to describe the natural history of SCN, including the specific mortality. DESIGN: Retrospective multinational study including SCN diagnosed between 1990 and 2014. RESULTS: 2622 patients were included. Seventy-four per cent were women, and median age at diagnosis was 58\u2005years (16-99). Patients presented with non-specific abdominal pain (27%), pancreaticobiliary symptoms (9%), diabetes mellitus (5%), other symptoms (4%) and/or were asymptomatic (61%). Fifty-two per cent of patients were operated on during the first year after diagnosis (median size: 40\u2005mm (2-200)), 9% had resection beyond 1\u2005year of follow-up (3\u2005years (1-20), size at diagnosis: 25\u2005mm (4-140)) and 39% had no surgery (3.6\u2005years (1-23), 25.5\u2005mm (1-200)). Surgical indications were (not exclusive) uncertain diagnosis (60%), symptoms (23%), size increase (12%), large size (6%) and adjacent organ compression (5%). In patients followed beyond 1\u2005year (n=1271), size increased in 37% (growth rate: 4\u2005mm/year), was stable in 57% and decreased in 6%. Three serous cystadenocarcinomas were recorded. Postoperative mortality was 0.6% (n=10), and SCN's related mortality was 0.1% (n=1). CONCLUSIONS: After a 3-year follow-up, clinical relevant symptoms occurred in a very small proportion of patients and size slowly increased in less than half. Surgical treatment should be proposed only for diagnosis remaining uncertain after complete workup, significant and related symptoms or exceptionally when exists concern with malignancy. This study supports an initial conservative management in the majority of patients with SCN

    Population policies and education: exploring the contradictions of neo-liberal globalisation

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    The world is increasingly characterised by profound income, health and social inequalities (Appadurai, 2000). In recent decades development initiatives aimed at reducing these inequalities have been situated in a context of increasing globalisation with a dominant neo-liberal economic orthodoxy. This paper argues that neo-liberal globalisation contains inherent contradictions regarding choice and uniformity. This is illustrated in this paper through an exploration of the impact of neo-liberal globalisation on population policies and programmes. The dominant neo-liberal economic ideology that has influenced development over the last few decades has often led to alternative global visions being overlooked. Many current population and development debates are characterised by polarised arguments with strongly opposing aims and views. This raises the challenge of finding alternatives situated in more middle ground that both identify and promote the socially positive elements of neo-liberalism and state intervention, but also to limit their worst excesses within the population field and more broadly. This paper concludes with a discussion outling the positive nature of middle ground and other possible alternatives

    Ethylene supports colonization of plant roots by the mutualistic fungus Piriformospora indica

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    The mutualistic basidiomycete Piriformospora indica colonizes roots of mono- and dicotyledonous plants, and thereby improves plant health and yield. Given the capability of P. indica to colonize a broad range of hosts, it must be anticipated that the fungus has evolved efficient strategies to overcome plant immunity and to establish a proper environment for nutrient acquisition and reproduction. Global gene expression studies in barley identified various ethylene synthesis and signaling components that were differentially regulated in P. indica-colonized roots. Based on these findings we examined the impact of ethylene in the symbiotic association. The data presented here suggest that P. indica induces ethylene synthesis in barley and Arabidopsis roots during colonization. Moreover, impaired ethylene signaling resulted in reduced root colonization, Arabidopsis mutants exhibiting constitutive ethylene signaling, -synthesis or ethylene-related defense were hyper-susceptible to P. indica. Our data suggest that ethylene signaling is required for symbiotic root colonization by P. indica
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