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Stefano J. Mandriota Mirna Tenan Adeline Nicolle Julia D. Jankowska Paolo Ferrari Jean-Christophe Tille Mary-Anne Durin Catherine M. Green Sebastien Tabruyn Daniela Moralli Andr-Pascal Sappino 《International journal of molecular sciences》2020,21(23)
Genomic instability is generally considered as a hallmark of tumorigenesis and a prerequisite condition for malignant transformation. Aluminium salts are suspected environmental carcinogens that transform mammary epithelial cells in vitro through unknown mechanisms. We report here that long-term culture in the presence of aluminium chloride (AlCl3) enables HC11 normal mouse mammary epithelial cells to form tumours and metastases when injected into the syngeneic and immunocompetent BALB/cByJ strain. We demonstrate that AlCl3 rapidly increases chromosomal structural abnormalities in mammary epithelial cells, while we failed to detect direct modulation of specific mRNA pathways. Our observations provide evidence that clastogenic activity—a well-recognized inducer of genomic instability—might account in part for the transforming abilities of aluminium in mammary epithelial cells. 相似文献
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C. Mendoza Z. Gonzalez E. Gordo B. Ferrari Y. Castro 《Journal of the European Ceramic Society》2018,38(2):495-500
The hardness and corrosion resistance of TiN coatings, processed by Electrophoretic Deposition (EPD) to cover polished and unpolished Ti substrates, have been evaluated. A deposition time of 5 min has been enough to obtain a cohesive layer of 7–8 μm in thickness. The coatings were thermally treated in vacuum atmosphere at 1200 °C for 1 h with heating and cooling rates of 5 °C min?1. The surfaces have been covered homogeneously optimizing the properties of the Ti substrates. Uniform and dense TiN coatings have been obtained onto polished substrates, while on unpolished Ti the nitrogen diffuses toward the substrate, moderately dissolving TiN coating. The nanohardness values of the polished samples have been increased from 2.8–4.8 GPa up to 6.5–8.5 GPa. Besides, the corrosion current density has been reduced more than one order of magnitude obtaining a protective efficiency of 82%. These values have been compared with other works in literature where authors used complex and costly processing techniques, demonstrating the strong impact of the colloidal processing over the specific properties of the material. 相似文献
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Slaven Jurić Marina Jurić Giovanna Ferrari Anet Režek Jambrak Francesco Donsì 《International Journal of Food Science & Technology》2021,56(10):4907-4914
Tomato processing residues are still rich in bioactive compounds that may be recovered and reused, with environmental and economic benefits. This short communication discloses for the first time that the high-pressure homogenisation (HPH) treatment of tomato residues in the presence of water and sunflower oil is able to promote the extraction of bioactive compounds concurrently to the formation of an oil-in-water emulsion stabilised by the micronized residues. The mechanical disruption effect of HPH improved the mass transfer of lycopene into the oil phase, and formed fine fibrous debris, improving stabilisation and visual appearance of the emulsion. Results showed a progressive increase of lycopene concentration in the cream phase up to 5 HPH passes and a concurrent reduction of its content in the pellet. Total polyphenols content and antioxidant activity in the aqueous phase gradually decreased when increasing the number of passes, suggesting their progressive transfer in the cream phase. The proposed process that relies on a purely physical treatment and uses only water/sunflower oil as extraction media resulted in the production of a lycopene-rich cream of potential use as a functional food ingredient. 相似文献
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María T. Colomer Lidia Zur Maurizio Ferrari Angel L. Ortiz 《Ceramics International》2018,44(11):11993-12001
Rhabdophane-type Eu3+,Tb3+-codoped LaPO4·nH2O single-crystal nanorods with the compositions La0.99999-xEuxTb0.00001PO4·nH2O (x?=?0–0.03), La0.99999-yTbyEu0.00001PO4·n′H2O (y?=?0–0.010), and La0.99999-zTbzEu0.000007PO4·n′′H2O (z?=?0–0.012) were hydrothermally synthesized with microwaves. It is shown that the Eu3+,Tb3+ codoping does not affect the thermal stability of these nanorods, which is due to the formation of substitutional solid solutions with both Eu3+ and Tb3+ replacing La3+ in the crystal lattice. Moreover, it is also shown that monazite-type Eu3+,Tb3+-codoped LaPO4 single-crystal nanorods can be obtained by calcining their rhabdophane-type Eu3+,Tb3+-codoped LaPO4·(n,n′ or n′′)H2O counterparts at moderate temperature in air, and that they are thermally stable. It is also observed that, for the same Eu3+,Tb3+-codoping content, the monazite-type Eu3+,Tb3+-codoped LaPO4 nanorods exhibit higher photoluminescent efficiency than the rhabdophane-type Eu3+,Tb3+-codoped LaPO4· (n,n′ or n′′)H2O nanorods. Moreover, it is found that the highest photoluminescence emission corresponds to the monazite-type La0.96999Eu0.02Tb0.00001PO4 nanorods for the La0.99999-xEuxTb0.00001PO4 system. However, for those compositions energy transfer from Tb3+ to Eu3+ does not occur. In addition, for an efficient energy transfer to occur, a content of at least 1?mol% Tb3+ is needed in all the studied materials. 相似文献
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Viviane Oliveira Soares Francisco Carlos Serbena Gabriel dos Santos Oliveira Crislaine da Cruz Robson Ferrari Muniz Edgar Dutra Zanotto 《Ceramics International》2021,47(4):4707-4714
Transparent and translucent glass-ceramics (GCs) are found in an increasing number of domestic and high-technology applications. In this paper, we evaluated and optimized the effects of two-stage heat treatments on the resulting crystalline phases and microstructure of a glass of the SiO2–Li2O–P2O5–TiO2–CaO–ZnO–Al2O3 system. The objective was to develop a transparent nanostructured glass-ceramic (GC). After numerous heat treatment trials, we found that a long nucleation period of 72 h at 455 °C followed by a crystal growth treatment at 660 °C for 2 h resulted in a highly translucent GC having homogenously distributed nanocrystals. The relatively high amount of P2O5 (2.5 mol%) induced the formation of lithium disilicate as the main crystal phase. We thus developed a GC having crystals under 50 nm, with a high crystallized fraction (52%vol. Li2Si2O5 and 26% vol Li2SiO3), transmittance of approximately 80% in the visible spectrum for 1.2 mm thick specimens, nano hardness of 8.7 ± 0.1 GPa (load of 400 mN), a high elastic modulus of 138 ± 3 GPa as measured by nanoindentation, and good flexural strength (350 ± 40 MPa) as measured by ball-on-3 balls tests. Due to its high content of Li+, this GC has the potential to be chemically strengthened and can be further developed to be used in a number of applications, such as on displays of electronic devices. 相似文献
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Bis(dipyridophenazine)(2‐(2′‐pyridyl)pyrimidine‐4‐carboxylic acid)ruthenium(II) Hexafluorophosphate: A Lesson in Stubbornness 下载免费PDF全文
Dr. Tanmaya Joshi Vanessa Pierroz Priv.‐Doz. Dr. Stefano Ferrari Prof. Dr. Gilles Gasser 《ChemMedChem》2014,9(7):1419-1427
Ruthenium complexes are currently considered to be among the most promising alternatives to platinum anticancer drugs. In this work, thirteen structural analogues and organelle/receptor‐targeting peptide bioconjugates of a cytotoxic bis(dppz)‐RuII complex [Ru(dppz)2(CppH)](PF6)2 ( 1 ) were prepared, characterized, and assessed for their cytotoxicity and cellular localization (CppH=2‐(2′‐pyridyl)pyrimidine‐4‐carboxylic acid; dppz=dipyrido[3,2‐a:2′,3′‐c]phenazine). It was observed that structural modifications (lipophilicity, charge, and size‐based) result in the cytotoxic potency of 1 being compromised. Confocal microscopy studies revealed that unlike 1 , the screened complexes/bioconjugates do not have a preferential accumulation in mitochondria. The results of this important structure–activity relationship strongly support our initial hypothesis that accumulation in mitochondria is crucial for 1 to exert its cytotoxic action. 相似文献
10.
Marusczak N Larose C Dommergue A Paquet S Beaulne JS Maury-Brachet R Lucotte M Nedjai R Ferrari CP 《The Science of the total environment》2011,409(10):1909-1915
Total mercury (THg) and methylmercury (MeHg) concentrations were measured in the muscle of Arctic charr (Salvelinus alpinus) and in the water column of 4 lakes that are located in the French Alps. Watershed characteristics were determined (6 coverage classes) for each lake in order to evaluate the influence of watershed composition on mercury and methylmercury concentrations in fish muscle and in the water column. THg and MeHg concentrations in surface water were relatively low and similar among lakes and watershed characteristics play a major role in determining water column Hg and MeHg levels. THg muscle concentrations for fish with either a standardized length of 220 mm, a standardized age of 5 years or for individualuals did not exceed the 0.5 mg kg− 1 fish consumption advisory limit established for Hg by the World Health Organization (WHO, 1990). These relatively low THg concentrations can be explained by watershed characteristics, which lead to short Hg residence time in the water column, and also by the short trophic chain that is characteristic of mountain lakes. Growth rate did not seem to influence THg concentrations in fish muscles of these lakes and we observed no relationship between fish Hg concentrations and altitude. This study shows that in the French Alps, high altitude lakes have relatively low THg and MeHg concentrations in both the water column and in Arctic charr populations. Therefore, Hg does not appear to present a danger for local populations and the fishermen of these lakes. 相似文献