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排序方式: 共有282条查询结果,搜索用时 15 毫秒
31.
Nunzia Novizio Raffaella Belvedere Emanuela Pessolano Silvana Morello Alessandra Tosco Pietro Campiglia Amelia Filippelli Antonello Petrella 《International journal of molecular sciences》2021,22(20)
The tumor microenvironment (TME) is a dynamic system where nontumor and cancer cells intercommunicate through soluble factors and extracellular vesicles (EVs). The TME in pancreatic cancer (PC) is critical for its aggressiveness and the annexin A1 (ANXA1) has been identified as one of the oncogenic elements. Previously, we demonstrated that the autocrine/paracrine activities of extracellular ANXA1 depend on its presence in EVs. Here, we show that the complex ANXA1/EVs modulates the macrophage polarization further contributing to cancer progression. The EVs isolated from wild type (WT) and ANXA1 knock-out MIA PaCa-2 cells have been administrated to THP-1 macrophages finding that ANXA1 is crucial for the acquisition of a protumor M2 phenotype. The M2 macrophages activate endothelial cells and fibroblasts to induce angiogenesis and matrix degradation, respectively. We have also found a significantly increased presence of M2 macrophage in mice tumor and liver metastasis sections previously obtained by orthotopic xenografts with WT cells. Taken together, our data interestingly suggest the relevance of ANXA1 as potential diagnostic/prognostic and/or therapeutic PC marker. 相似文献
32.
Emanuela Falletti Fabrizio Sellone Candida Spillard David Grace 《International Journal of Wireless Information Networks》2006,13(1):59-75
The interest of the scientific and industrial communities on the application of high altitude stratospheric platforms to communications
is increasingly growing. Several research projects and field trials are being carried out by international consortia and specific
portions of the electromagnetic spectrum have been allocated by the International Telecommunications Union (ITU) for communications
applications. The channel experienced by such systems plays a key role for the provision of reliable communications services
but, unfortunately, its inherent characteristics are substantially different from those of other channel typologies. Therefore,
in order to design and simulate effective propagation impairment mitigation techniques such as adaptive modulation and coding
or adaptive beamforming and equalization algorithms, an ad hoc channel model and simulator is definitively required. In this paper a novel channel model and a related channel simulator
especially tailored for HAP-based communication systems are presented. The model is conceived for link-level simulations of
point-to-point communication links, wherein both the transmitter and the receiver may be equipped with an array of antennas.
Peculiar physical effects of the stratospheric channel are taken into account as well as impairments due to the possible presence
of scatterers and relative movement of both transmitting and receiving stations. The structure of the channel simulator has
been conceived to maintain the computational burden at required by the channel simulator is kept low by an efficient tapped
delay line implementation.
This work is supported by the CAPANINA project (FP6 IST-2003-506745): Communications from aerial platform networks delivering
broadband communications for all, http://www.capanina.org.
相似文献
Emanuela FallettiEmail: |
33.
Baffone W Casaroli A Citterio B Pierfelici L Campana R Vittoria E Guaglianone E Donelli G 《International journal of food microbiology》2006,107(1):83-91
Water is known as one of the main transmission routes of Campylobacter and contributes to increase the number of sporadic infections and outbreaks. Campylobacter jejuni persists in the environment, especially in water, in a viable but non-culturable (VBNC) form that is thought to be a possible cause of water-borne outbreaks. In this study, we evaluated the loss of culturability and viability of 9 C. jejuni strains of clinical origin and one ATCC reference strain when kept at 4 degrees C in artificial sea water (ASW). Culturability was measured as colony-forming units while viability was evaluated by CTC-DAPI double staining and the combined CTC-specific fluorescent antibody technique (CTC-FA). When cultured on Columbia Agar plates, strains exhibited different growth profiles which allowed to classify them into three different groups. Both techniques used to monitor the viability of the bacterial cells showed that C. jejuni strains survived in the VBNC form in the microcosms through a period lasting from 138 to 152 days. The recovery of C. jejuni VBNC forms to culturability, as evidenced by cell division, was obtained by passage in the mouse intestine. Our results indicate that C. jejuni VBNC cells were able to remain in this state for a few months and regain their culturability after in vivo passage depending on their lasting in the VBNC state, which affects the number of respiring bacteria. In fact, the resuscitation was achieved when the number of respiring bacteria became higher than 10(4) cell/ml. Therefore, a relatively high microbial titer of respiring bacteria in the VBNC state seems to be important for the resuscitation and subsequent intestinal colonisation. 相似文献
34.
Tiziana Siciliano Marco TeporeAlessandra Genga Gioacchino MicocciAntonio Tepore Emanuela Filippo 《Materials Chemistry and Physics》2012
In this paper, we report the obtention of In2O3 nanostructured microwires by the decomposition thermal treatment of InSe single crystal in two-steps under an oxygen–ammonia flow without the presence of any catalyst. Long In2O3 microwires with uniform shape and homogeneous surface were first synthesized through thermal treatment of InSe single crystal at temperature of about 640 °C; then, furnace temperature was increased to 750 °C and, as annealing time proceeded, the obtained microwires served as substrates on which nanorod branches grew. The shape and the structure of the microarchitectures were characterized by means scanning electron microscopy, transmission electron microscopy, selected area diffraction pattern, X-Ray diffraction and Raman spectroscopy. Our results indicated that In2O3 primary wires with a clean surface grew in the [100] direction and that the secondary protuberances grew in the [011] direction. A possible growth mechanism of the hierarchical microwires was also proposed. 相似文献
35.
Toschi F Orlanducci S Tamburri E Guglielmotti V Terranova ML Di Carlo A Reale A Falessi C 《Journal of nanoscience and nanotechnology》2010,10(12):8336-8340
The thermal performances of nanocomposite layers formed by Single-walled Carbon Nanotubes (SWCNT) dispersed in 2 different kind of polydimethyl-siloxane (PDMSO) matrices has been investigated by measuring the thermal resistance under conditions similar to the ones used for thermal management in microelectronics. A series of nanocomposite samples with thickness in the range 25 microm(-1) cm have been tested. The nanocomposites were prepared varying the amounts of nanotubes embedded in the matrix (from 0.1 to 5%w). In some cases also microsized graphites were mixed to the nanotube's fillers. For 25 micron thick layers, the thermal resistance of the neat silicone specimen can be reduced of 54% with the addition of 2%w carbon nanotubes. The variation of thermal conductivity as a function of the SWCNT's loading is reported and discussed. Furthermore the dispersion's effects of the nanotubes in the layers and the effects on the realization of a net-like system have been investigated. 相似文献
36.
37.
Annurca (Malus pumila Miller cv. Annurca) apple as a functional food for the contribution to a healthy balance of plasma cholesterol levels: results of a randomized clinical trial 下载免费PDF全文
38.
Mara Di Giulio Viviana di Giacomo Emanuela Di Campli Soraya Di Bartolomeo Susi Zara Guido Pasquantonio Amelia Cataldi Luigina Cellini 《Journal of materials science. Materials in medicine》2013,24(8):1977-1983
This study aimed to investigate the effect of saliva on Streptococcus mitis free cells and on S. mitis/human gingival fibroblasts (HGFs) co-culture model, in presence of 2-hydroxyethyl-methacrylate (HEMA). The bacterial aggregation both in the planktonic phase and on HGFs, as well as the apoptotic and necrotic eukaryotic cells amount were analyzed, in presence of saliva and/or HEMA. The aggregation test revealed a significant saliva aggregation effect on S. mitis strains compared to the untreated sample. No significant differences were recorded in the amount of culturable bacteria in all studied conditions; however, from microscopy images, the saliva/HEMA combining effect induced a significant bacterial aggregation and adhesion on HGFs. HEMA treatment decreased viable eukaryotic cell number with a parallel increment of necrotic cells, but when saliva was added to the co-culture, the viable cells percentage increased to a value comparable to the control sample. 相似文献
39.
Hongying Hou Riccardo Polini Maria Luisa Di Vona Xianxi Liu Emanuela Sgreccia Jean-François Chailan Philippe Knauth 《International Journal of Hydrogen Energy》2013
SPEEK has been widely considered as a promising alternative to Nafion® membrane for PEMFC. However, a conflict between high degree of sulfonation (DS) and poor mechanical strength needs to be resolved prior to wide application. In this work, such an effort was made by double strategies: thermal crosslinking and adding nanodiamond into high DS SPEEK matrix. The obtained sample was characterized by XRD, high resolution TGA and dynamic mechanical analysis (DMA). Small part of –SO3H groups within SPEEK matrix participated in the crosslinking process by forming –SO2– bridge bond, while the rest large part of –SO3H groups still contributed to the proton transport. Mechanical and thermal stability of SPEEK membrane were modified by crosslinking-induced three-dimensional (3D) networks and interactions of SPEEK with nanodiamond. In addition, the water uptakes of composite membranes were also slightly improved possibly due to the capillary condensation in nanodiamond particles. 相似文献
40.
Galli U Ercolano E Carraro L Blasi Roman CR Sorba G Canonico PL Genazzani AA Tron GC Billington RA 《ChemMedChem》2008,3(5):771-779
One of the great challenges of medicinal chemistry is to create novel, effective, chemotherapeutic agents that show specificity for cancer cells combined with low systemic toxicity. A novel idea is to target the enzymes of the NAD biosynthesis and recycling pathways given that cancer cells display a higher NAD turnover rate than healthy cells. To this end, the compound FK866 (APO866; (E)-N-[4-(1-benzoylpiperidin-4-yl) butyl]-3-(pyridin-3-yl) acrylamide), which blocks nicotinamide phosphoribosyltransferase (NMPRTase) has entered clinical trials as a potential chemotherapeutic agent. Here we report the synthesis of analogues of FK866 synthesized by click chemistry. 相似文献