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Giulia Andreani Enea Ferlizza Riccardo Cabbri Micaela Fabbri Elisa Bellei Gloria Isani 《International journal of molecular sciences》2021,22(1)
The recent introduction of the Asian yellow-legged hornet, Vespa velutina, into Europe has raised concern regarding the threat to honeybees and the competition with the European hornet, Vespa crabro. The aim of this study was to investigated essential (Mg, Fe, Zn, Cu) and non-essential (Cd and Pb) elements in these two species. Element concentrations were determined in the whole body and separately in the head, thorax and abdomen using atomic absorption spectrometry (AAS). The changes in essential element concentration and speciation during metamorphosis were also studied using size exclusion chromatography followed by AAS and proteomic analysis. In both species, the essential elements were more concentrated in the abdomen due to the presence of fat bodies. Magnesium, Fe and Zn concentrations were significantly higher in V. crabro than in V. velutina and could have been related to the higher aerobic energy demand of the former species required to sustain foraging flight. Low concentrations of Cd and Pb were indicative of low environmental exposure. The concentration and speciation of essential elements, particularly Fe, varied among the developmental stages, indicating a modification of ligand preferences during metamorphosis. Overall, the results in the present study provide a better understanding of the hornet metal metabolism and a foundation for additional studies. 相似文献
3.
David Diaz Elisa Lopez-Dolado Sergio Haro Jorge Monserrat Carlos Martinez-Alonso Dimitrios Balomeros Agustín Albillos Melchor Alvarez-Mon 《International journal of molecular sciences》2021,22(2)
Our aim was to investigate the subset distribution and function of circulating monocytes, proinflammatory cytokine levels, gut barrier damage, and bacterial translocation in chronic spinal cord injury (SCI) patients. Thus, 56 SCI patients and 28 healthy donors were studied. The levels of circulating CD14+highCD16−, CD14+highCD16+, and CD14+lowCD16+ monocytes, membrane TLR2, TLR4, and TLR9, phagocytic activity, ROS generation, and intracytoplasmic TNF-α, IL-1, IL-6, and IL-10 after lipopolysaccharide (LPS) stimulation were analyzed by polychromatic flow cytometry. Serum TNF-α, IL-1, IL-6 and IL-10 levels were measured by Luminex and LPS-binding protein (LBP), intestinal fatty acid-binding protein (I-FABP) and zonulin by ELISA. SCI patients had normal monocyte counts and subset distribution. CD14+highCD16− and CD14+highCD16+ monocytes exhibited decreased TLR4, normal TLR2 and increased TLR9 expression. CD14+highCD16− monocytes had increased LPS-induced TNF-α but normal IL-1, IL-6, and IL-10 production. Monocytes exhibited defective phagocytosis but normal ROS production. Patients had enhanced serum TNF-α and IL-6 levels, normal IL-1 and IL-10 levels, and increased circulating LBP, I-FABP, and zonulin levels. Chronic SCI patients displayed impaired circulating monocyte function. These patients exhibited a systemic proinflammatory state characterized by enhanced serum TNF-α and IL-6 levels. These patients also had increased bacterial translocation and gut barrier damage. 相似文献
4.
Elisa Mascolo Francesco Liguori Lorenzo Stufera Mecarelli Noemi Amoroso Chiara Merigliano Susanna Amadio Cinzia Volont Roberto Contestabile Angela Tramonti Fiammetta Vernì 《International journal of molecular sciences》2021,22(2)
Maturity-onset diabetes of the young (MODY) type 2 is caused by heterozygous inactivating mutations in the gene encoding glucokinase (GCK), a pivotal enzyme for glucose homeostasis. In the pancreas GCK regulates insulin secretion, while in the liver it promotes glucose utilization and storage. We showed that silencing the Drosophila GCK orthologs Hex-A and Hex-C results in a MODY-2-like hyperglycemia. Targeted knock-down revealed that Hex-A is expressed in insulin producing cells (IPCs) whereas Hex-C is specifically expressed in the fat body. We showed that Hex-A is essential for insulin secretion and it is required for Hex-C expression. Reduced levels of either Hex-A or Hex-C resulted in chromosome aberrations (CABs), together with an increased production of advanced glycation end-products (AGEs) and reactive oxygen species (ROS). This result suggests that CABs, in GCK depleted cells, are likely due to hyperglycemia, which produces oxidative stress through AGE metabolism. In agreement with this hypothesis, treating GCK-depleted larvae with the antioxidant vitamin B6 rescued CABs, whereas the treatment with a B6 inhibitor enhanced genomic instability. Although MODY-2 rarely produces complications, our data revealed the possibility that MODY-2 impacts genome integrity. 相似文献
5.
Matteo Di Giosia Alice Soldà Markus Seeger Andrea Cantelli Fabio Arnesano Maria I. Nardella Vincenzo Mangini Francesco Valle Marco Montalti Francesco Zerbetto Stefania Rapino Matteo Calvaresi Vasilis Ntziachristos 《Advanced functional materials》2021,31(20):2101527
Fullerenes are candidates for theranostic applications because of their high photodynamic activity and intrinsic multimodal imaging contrast. However, fullerenes suffer from low solubility in aqueous media, poor biocompatibility, cell toxicity, and a tendency to aggregate. C70@lysozyme is introduced herein as a novel bioconjugate that is harmless to a cellular environment, yet is also photoactive and has excellent optical and optoacoustic contrast for tracking cellular uptake and intracellular localization. The formation, water-solubility, photoactivity, and unperturbed structure of C70@lysozyme are confirmed using UV-visible and 2D 1H, 15N NMR spectroscopy. The excellent imaging contrast of C70@lysozyme in optoacoustic and third harmonic generation microscopy is exploited to monitor its uptake in HeLa cells and lysosomal trafficking. Last, the photoactivity of C70@lysozyme and its ability to initiate cell death by means of singlet oxygen (1O2) production upon exposure to low levels of white light irradiation is demonstrated. This study introduces C70@lysozyme and other fullerene-protein conjugates as potential candidates for theranostic applications. 相似文献
6.
Martinez-Yelmo Isaias Alvarez-Horcajo Joaquin Briso-Montiano Miguel Lopez-Pajares Diego Rojas Elisa 《Telecommunication Systems》2019,72(4):555-565
Telecommunication Systems - The Software-Defined Networking (SDN) architecture decouples the control plane from the data plane, but it does not explicitly state where the control should be located.... 相似文献
7.
Stefania Korontzi David P. Roy Christopher O. Justice 《Remote sensing of environment》2004,92(2):255-275
This paper uses three recently generated southern African satellite burned area products for the month of September 2000 in a sensitivity study of regional biomass burning emissions for a number of trace gases and particulates. Differences in the extent and location of areas burned among products generated from Moderate Resolution Imaging Spectroradiometer (MODIS), Systeme Pour l'Observation de la Terre (SPOT-VEGETATION), and Along Track Scanning Radiometer (ATSR-2) data are significant and result in different emissions estimates for woodland and grassland land cover types. Due to the different emission profiles in woodlands and grasslands, favoring relatively more products of incomplete combustion in woodlands compared with products of complete combustion in grasslands in the late dry season, these changes are not proportional to the differences in the burned area amounts. The importance of accurate burned area information not just in terms of the total area but also in terms of its spatial distribution becomes apparent from our modeling results. This paper highlights the urgent need for satellite data producers to provide accuracy assessments associated with satellite-derived products. Preferably, these accuracy data will be spatially explicit, or defined in a way that can be applied in a spatially explicit modeling context, to enable emissions uncertainties to be defined with respect to different landscape units in support of greenhouse gas emissions reporting. 相似文献
8.
Massimiliano Corsini Elisa Drelie Gelasca Touradj Ebrahimi Mauro Barni 《Multimedia, IEEE Transactions on》2007,9(2):247-256
This paper addresses the problem of assessing distortions produced by watermarking 3D meshes. In particular, a new methodology for subjective evaluation of the quality of 3D objects is proposed and implemented. Two objective metrics derived from measures of surface roughness are then proposed and their efficiency to predict the perceptual impact of 3D watermarking is assessed and compared with the state of the art. Results obtained show good correlations between the proposed objective metrics and subjective assessments by human observers 相似文献
9.
Zhao Donghui Wang Hua Chen Guorong Stefania Baccaro Angelica Cecilia Mauro Falconieri L. Pilloni 《Journal of the American Ceramic Society》2006,89(11):3582-3584
Gamma-ray irradiations induced various alterations in sulfur- and selenium-based chalcogenide glasses. The absorbed dose was in the range of 0.01–3.6 MGy. The glasses exhibit prominent sensitivity to γ-ray irradiation, characterized by changes in some of the physical properties of the glasses, e.g., optical transmission, optical band gap, density, and thermal expansion coefficient. The effects on glass structure and microscopic morphology were also studied by Raman spectra and scanning electron microscopic observations. 相似文献
10.
Emilio Marengo Valentina Longo Elisa Robotti Marco Bobba Fabio Gosetti Orfeo Zerbinati Silvana Di Martino 《应用聚合物科学杂志》2008,109(6):3975-3982
Principal component regression (PCR), partial least squares (PLS), StepWise ordinary least squares regression (OLS), and back‐propagation artificial neural network (BP‐ANN) are applied here for the determination of the propylene concentration of a set of 83 production samples of ethylene–propylene copolymers from their infrared spectra. The set of available samples was split into (a) a training set, for models calculation; (b) a test set, for selecting the correct number of latent variables in PCR and PLS and the end point of the training phase of BP‐ANN; (c) a production set, for evaluating the predictive ability of the models. The predictive ability of the models is thus evaluated by genuine predictions. The model obtained by StepWise OLS turned out to be the best one, both in fitting and prediction. The study of the breakdown number of samples to be included in the training set showed that at least 52 experiments are necessary to build a reliable and predictive calibration model. It can be concluded that FTIR spectroscopy and OLS can be properly employed for monitoring the synthesis or the final product of ethylene–propylene copolymers, by predicting the concentration of propylene directly along the process line. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献