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1.
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
2.
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
3.
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
4.
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
5.
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
6.
Tsuji M. Shigesawa H. Frezza F. Lampariello P. Oliner A.A. 《Antennas and Propagation, IEEE Transactions on》1998,46(7):1047-1055
For pt.II ibid., vol.46, no.7, p.1042-46. The article describes the measurements that verify the validity of the theoretical expressions for this new type of antenna. Measurements were made both at millimeter wavelengths (40 to 60 GHz) and in the X-band (8 to 12 GHz) frequency range and of two different quantities: the propagation wavenumbers β and α and radiation patterns. Comparisons were made with numerical values obtained from the theoretical expressions derived in parts I and II and very good agreement was found in all cases 相似文献
7.
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
8.
Lampariello P. Frezza F. Shigesawa H. Tsuji M. Oliner A.A. 《Antennas and Propagation, IEEE Transactions on》1998,46(7):1032-1041
A new leaky-wave antenna is presented that possesses many desirable features and is suitable for application to both the millimeter-wave and microwave ranges. These desirable features, some of which are unusual, include a simple configuration, a wide flexibility in the range of available beamwidths, the ability to control the beamwidth and the direction of the beam essentially independently, and negligible cross polarization at all scan angles. The antenna structure consists of a parallel-plate stub guide of small height, less than a half wavelength, located off center on the top of rectangular waveguide. The beamwidth is easily controlled from very wide to very narrow by adjusting the stub width or location. The article presents the principle of operation and the theory, employing a new transverse equivalent network that is accurate, but also simple, so that it permits rapid and inexpensive numerical calculations 相似文献
9.
Total parenteral nutrition (TPN) is used routinely to maintain patients with the Short Bowel Syndrome (SBS). Until recently, TPN has been the only available therapeutic modality for patients with SBS. Currently, it is the treatment of choice for such individuals and occasionally, when the loss of bowel is extensive, it may be the only way of maintaining life. Unfortunately, TPN is expensive and markedly restrains an individual's lifestyle. Despite the overall success of TPN, the numerous risks associated with its use and the many complications of having an intravenous indwelling for years have served as the stimulus for alternative treatments such as small bowel transplantation (SBT). The first attempts at small bowel transplantation in clinical medicine were by Detterling almost 25 years ago. Patient death or graft loss in these early attempts was caused by the failure to control graft rejection and/or the inability to prevent Graft Versus Host Disease (GVHD). A stimulus for renewed clinical interest in SBT was provided by Starzl et al in 1988 with a report of prolonged graft survival without graft rejection or GVHD in a patient who was the recipient of a multivisceral graft consisting of the entire small bowel and other abdominal organs. Since 1964, 78 Small Bowel transplants have been performed in humans. Several variations of the multivisceral procedure in which the liver and the small bowel constitute the major components of the graft were adopted. The longest survival has been in a child who is still alive with a working graft for more than two years, as reported by Goulet from Paris in 1989. The introduction in SBT of the new immunosuppressive agent FK 506 had provided results which are superior to those achieved with Cyclosporine A (CsA). This latter observation prompted the Pittsburgh group to initiate a large series of isolated and composite intestinal grafts. The remarkable results have demonstrated the clinical utility of intestinal transplantation. This paper will try to summarize the history of the small bowel transplantation until the end of the year 1992, with the current progress in use today. 相似文献
10.