61 research outputs found

    Identification and quantification of polystyrene microplastics in marine sediments facing a river mouth through NMR spectroscopy

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    Accurate identification and quantification of microplastic pollution in marine sediments are crucial for assessing their ecological impact. In this study, we explored the potential of Nuclear Magnetic Resonance (NMR) spectroscopy as an analytical tool for the analysis of microplastics in complex environmental matrices such as marine sediments. Two common plastic polymers, polystyrene (PS) and acrylonitrile butadiene styrene (ABS), were investigated. The marine sediments facing the Tiber River mouth (Italy) were collected according to a bathy-metric gradient. Results demonstrated the successful detection and quantification of PS in all sediment samples (within a range of 12.3-64.6 mu g/L), while no ABS significant signals were found. An increment trend with depth was observed in the PS signal, relatable to its physicochemical properties and the Tiber River plume hydrodynamic characteristics. The NMR's non-destructive nature and minimal sample preparation represent a promising avenue for standardizing protocols to assess the microplastic distribution and impact in marine sediments

    Evaluation of the effects of cyclododecane on oil paintings

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    The solubility of oil paint components during the application of cyclododecane in solvent mixtures was evaluated in order to predict if the application of cyclododecane during restoration may significantly alter the chemical state of the paint layer in oil paintings. The chemical affinity between some of the oil binder components and non-polar cyclododecane could potentially lead to interactions or leaching during the application. In order to investigate these effects a set of samples taken from oil paintings from the early 1900s and 2008, were treated with cyclododecane in a solution, melted, and sprayed as aerosol. The samples were also submitted to a comparative extractive treatment with cyclododecane and organic solvents of different polarities. After the treatments, the extracted components were analysed by gas chromatography-mass spectrometry (GC/MS), which provided detailed molecular information on the composition of the extracts, together with a quantitative profile of fatty acids in extracted triglycerides, after saponification and derivatisation. The results show that applications of cyclododecane both as a spray and in a saturated solution in a hydrocarbon solvent determine the extraction of a low amount of lipids from the paint. On the other hand, when cyclododecane is applied in the melted form, there is an extraction of lipid components of the paint into the treatment solution

    Bone Lesions in a Young Dog and a NEEM (Azadirachta indica) Spray as the Only Preventive Measure against Leishmaniasis: A Case Report

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    As the spread of canine leishmaniasis (CanL) is increasing throughout the world, the need for effective agents to prevent its transmission has intensified. In this case report, an intact 1.5-year-old male French bulldog was presented for treatment of severe, sudden, and constant lameness on his right hindlimb, which had started approximately four months previously and was unresponsive to routine nonsteroidal anti-inflammatory drugs. A Neem oil-based product was sprayed three times a week on the dog’s coat for about fourteen months as the only prophylactic measure against CanL. The orthopedic examination revealed grade 3–4 lameness and marked atrophy of the thigh muscles with swollen and painful right stifle joint. The radiological investigation showed polyostotic periosteal proliferation at both hindlimbs. The diagnosis of CanL was established by examination of fine- needle aspiration of lymph nodes (left prescapular, right and left popliteal) and immunofluorescence antibody testing. A leishmanicidal therapeutic protocol was prescribed. Within ten days of starting the therapy, the dog was significantly less lame, and eight months later radiographic examination revealed complete regression of the bone lesions. Some owners resort to a naturalistic approach for CanL prevention, also using products that have not been clinically evaluated. Neem oil is thought to prevent sandfly bites in dogs. Some laboratory and field studies have identified Neem oil as a possible alternative herbal drug that is repellent to sandflies. However, the clinical, laboratory, and radiographic findings clearly show that the Neem oil spray formulation used in this case report was not an effective means of CanL prevention. There is no clinical evidence in support of Neem oil-based products for the protection of dogs against CanL transmission. As Neem oil has previously been shown to be somewhat volatile, this case report suggests that even though it is a very effective repellent against sandflies, in practice, its effect on the dogs’ coat was only short-lived

    Formyl-peptide Receptor Agonists and Amorphous SiO2-NPs Synergistically and Selectively Increase the Inflammatory Responses of Human Monocytes and PMNs

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    We tested whether amorphous SiO2-NPs and formyl-peptide receptor (FPRs) agonists synergistically activate human monocytes and neutrophil polymorphonuclear granulocytes (PMNs). Peptide ligands specifically binding to FPR1 (f-MLP) and to FPR2 (MMK-1, WKYMVM and WKYMVm) human isoforms did not modify the association of SiO2-NPs to both cell types or their cytotoxic effects. Similarly, the extent of CD80, CD86, CD83, ICAM-1 and MHCII expression in monocytes treated with SiO2-NPs was not significantly altered by any FPRs agonist. However, FPR1 stimulation with f-MLP strongly increased the secretion of IL-1β, IL-6 and IL-8 by human monocytes, and of IL-8 by PMNs in the presence of SiO2-NPs, due to the synergic stimulation of gene transcription. FPR2 agonists also up-modulated the production of IL-1β induced by monocytes treated with SiO2-NPs. In turn, SiO2-NPs increased the chemotaxis of PMNs toward FPR1-specific ligands, but not toward FPR2-specific ones. Conversely, the chemotaxis of monocytes toward FPR2-specific peptides was inhibited by SiO2-NPs. NADPH-oxidase activation triggered by FPR1- and FPR2-specific ligands in both cell types was not altered by SiO2-NPs. Microbial and tissue danger signals sensed by FPRs selectively amplified the functional responses of monocytes and PMNS to SiO2-NPs, and should be carefully considered in the assessment of the risk associated with nanoparticle exposure

    Life-stage dependent response of the epiphytic lichen Lobaria pulmonaria to climate

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    Lichens are poikilohydric organisms, whose internal water content tends to reflect external humidity conditions. After drying, they can reactivate their metabolic activity through water vapor uptake or liquid water input. Thus, lichen water-related functional traits are important as they are involved in the duration of the hydrated period. Models predicting the effect of environmental conditions on lichens are based mainly on the presence or absence of adult thalli. Nevertheless, ecological conditions required by lichens might vary during their life cycle, for example during propagule establishment or in the first stages of thallus development. Little is known about the different ecological requirements at the different development stages in lichens. In this work, we measured water holding capacity (WHC) and specific thallus mass (STM) of adult and juvenile thalli of the model species Lobaria pulmonaria along a climatic gradient to constrain the processbased model LiBry. The LiBry model allows accounting for the productivity of lichens with different physiological strategies under various environmental conditions. We simulated the activity and performance of adult and juvenile thalli in 9 regions of Italy and Corsica. The model was used to test if adult thalli of L. pulmonaria have a higher survival probability due to their higher aerodynamic resistance. In the current climatic condition, the LiBry model predicts a higher survival probability of adults with decreasing absolute survival rates of both life stages with increasing temperature. Adult thalli also result in having higher active time, STM, and relative growth rate (RGR). We discuss the main implications of our simulation outputs, provide future perspectives and possible implementations of the LiBry mode

    EVALUATION OF SHEEP GRAZING EFFECTS ON NEMATODE COMMUNITY, INSECT INFESTATION AND SOIL FERTILITY IN SWEET CHESTNUT ORCHARDS: A CASE OF STUDY

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    In sweet chestnut cultivation, important ecosystem in Europe, the moderate sheep grazing practice may have some beneficial effects in organic farming. Its impact, on soil fertility, soil nematode community and level of fruit infested by tortricids and curculionids was evaluated in a case of study in Tuscany (Central Italy). An organic farm with sheep grazing system (SG) based on long-term field application was compared with an adjacent organic farm with poultry manure system (PM). In both managements, no treatment to control pests and diseases was applied and 0.19 kg /plant of nitrogen were distributed. SG increased twice the amount of organic C, total N and available P than PM. Moreover, the salinity effect of uric acid significantly increased the pH values in SG (from 5.0 to 6.2). The greatest accumulation of organic matter under SG provided stability in nematode community structure and the plant parasitic nematodes decreased. The analysis on the nematodes emerged from Galleria mellonella larvae, revealed that the abundance of native entomopathogenic nematodes was low and not effective to control insect pests. The sheep demonstrated to be the effective predators of tortricid and weevil larvae and in November, the total infestation was significantly lower in SG (34.3%) than PM (54.3%)

    Endophytic Bacteria Associated with Origanum heracleoticum L. (Lamiaceae) Seeds

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    Seed-associated microbiota are believed to play a crucial role in seed germination, seedling establishment, and plant growth and fitness stimulation, due to the vertical transmission of a core microbiota from seeds to the next generations. It might be hypothesized that medicinal and aromatic plants could use the seeds as vectors to vertically transfer beneficial endophytes, providing plants with metabolic pathways that could influence phytochemicals production. Here, we investigated the localization, the structure and the composition of the bacterial endophytic population that resides in Origanum heracleoticum L. seeds. Endocellular bacteria, surrounded by a wall, were localized close to the aleurone layer when using light and transmission electron microscopy. From surface-sterilized seeds, cultivable endophytes were isolated and characterized through RAPD analysis and 16S RNA gene sequencing, which revealed the existence of a high degree of biodiversity at the strain level and the predominance of the genus Pseudomonas. Most of the isolates grew in the presence of six selected antibiotics and were able to inhibit the growth of clinical and environmental strains that belong to the Burkholderia cepacia complex. The endophytes production of antimicrobial compounds could suggest their involvement in plant secondary metabolites production and might pave the way to endophytes exploitation in the pharmaceutical field

    Metal line emission from galaxy haloes at z~1

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    We present a study of the metal-enriched halo gas, traced using MgII and [OII] emission lines, in two large, blind galaxy surveys - the MUSE (Multi Unit Spectroscopic Explorer) Analysis of Gas around Galaxies (MAGG) and the MUSE Ultra Deep Field (MUDF). By stacking a sample of ~600 galaxies (stellar masses M* ~10^{6-12} Msun), we characterize for the first time the average metal line emission from a general population of galaxy haloes at 0.7 <= z <= 1.5. The MgII and [OII] line emission extends farther out than the stellar continuum emission, on average out to ~25 kpc and ~45 kpc, respectively, at a surface brightness (SB) level of 10^{-20} erg/s/cm2/arcsec2. The radial profile of the MgII SB is shallower than that of the [OII], suggesting that the resonant MgII emission is affected by dust and radiative transfer effects. The [OII] to MgII SB ratio is ~3 over ~20-40 kpc, also indicating a significant in situ origin of the extended metal emission. The average SB profiles are intrinsically brighter by a factor ~2-3 and more radially extended by a factor of ~1.3 at 1.0 < z <= 1.5 than at 0.7 <= z <= 1.0. The average extent of the metal emission also increases independently with increasing stellar mass and in overdense group environments. When considering individual detections, we find extended [OII] emission up to ~50 kpc around ~30-40 percent of the group galaxies, and extended (~30-40 kpc) MgII emission around two z~1 quasars in groups, which could arise from outflows or environmental processes.Comment: 24 pages, 21 figures, 2 tables, accepted for publication in MNRA

    C1q-Mediated Complement Activation and C3 Opsonization Trigger Recognition of Stealth Poly(2-methyl-2-oxazoline)-Coated Silica Nanoparticles by Human Phagocytes

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    Poly(2-methyl-2-oxazoline) (PMOXA) is an alternative promising polymer to poly(ethylene glycol) (PEG) for design and engineering of macrophage-evading nanoparticles (NPs). Although PMOXA-engineered NPs have shown comparable pharmacokinetics and in vivo performance to PEGylated stealth NPs in the murine model, its interaction with elements of the human innate immune system has not been studied. From a translational angle, we studied the interaction of fully characterized PMOXA-coated vinyltriethoxysilane-derived organically modified silica NPs (PMOXA-coated NPs) of approximately 100 nm in diameter with human complement system, blood leukocytes, and macrophages and compared their performance with PEGylated and uncoated NP counterparts. Through detailed immunological and proteomic profiling, we show that PMOXA-coated NPs extensively trigger complement activation in human sera exclusively through the classical pathway. Complement activation is initiated by the sensing molecule C1q, where C1q binds with high affinity (Kd = 11 \ub1 1 nM) to NP surfaces independent of immunoglobulin binding. C1q-mediated complement activation accelerates PMOXA opsonization with the third complement protein (C3) through the amplification loop of the alternative pathway. This promoted NP recognition by human blood leukocytes and monocyte-derived macrophages. The macrophage capture of PMOXA-coated NPs correlates with sera donor variability in complement activation and opsonization but not with other major corona proteins, including clusterin and a wide range of apolipoproteins. In contrast to these observations, PMOXA-coated NPs poorly activated the murine complement system and were marginally recognized by mouse macrophages. These studies provide important insights into compatibility of engineered NPs with elements of the human innate immune system for translational steps
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