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11.
Simona Caudo Gabriele Centi Chiara Genovese Siglinda Perathoner 《Topics in Catalysis》2006,40(1-4):207-219
Homogeneous (Cu2+ ions) and heterogeneous (Cu2+-pillared clay) Fenton-like catalysts have been compared in the conversion of p-coumaric acid. The performances of the two classes of catalysts are similar for an analogous amount of copper, but there are
some relevant differences in terms of (i) the presence of an induction time, (ii) the turnover frequency, (iii) the efficiency
in the use of H2O2, (iv) the initial attack of p-coumaric acid (hydroxylation on the aromatic ring or oxidative attack on the double bond of the lateral chain), and (v) the
effect of dissolved oxygen on the removal of total organic carbon (TOC). These differences were interpreted in terms of reaction
network of generation of radical oxygen species and of organics conversion. The possible formation of a surface peroxo adduct
coordinated to a copper binulcear site was also evidenced for the solid heterogeneous catalyst. 相似文献
12.
A systematic reactivity study of N2O, NO, and NO2 on highly dispersed CuO phases over modified silica supports (SiO2–Al2O3, SiO2–TiO2, and SiO2–ZrO2) has been performed. Different reaction paths for the nitrogen oxide species abatement were studied: from direct decomposition (N2O) to selective reductions by hydrocarbons (N2O, NO, and NO2) and oxidation (NO to NO2). The oxygen concentration, temperature, and contact time, were varied within suitable ranges in order to investigate the activity and in particular the selectivity in the different reactions studied. The support deeply influenced the catalytic properties of the active copper phase. The most acidic supports, SiO2–Al2O3 and SiO2–ZrO2, led to a better activity and selectivity of CuO for the reactions of N2O, NO, and NO2 reductions and N2O decomposition than SiO2–TiO2. The catalytic results are discussed in terms of actual turnover frequencies starting from the knowledge of the copper dispersion values. 相似文献
13.
The phase behavior of binary blends of acrylonitrile/methyl acrylate/butadiene terpolymer (B210) and poly(ethylene-co-maleic anhydride) (PEMA) was examined based on thermal analysis and optical microscopy. Miscibility of these polymer blends was recognized over a wide range of compositions. The appearance of phase separation during subsequent heatings above the glass transition temperature (Tg) of these blends was associated with a lower critical solution temperature (LCST) behavior. Rheological characteristics such as shear storage modulus (G′), loss modulus (G″) and complex viscosity have been shown to depend on the amount of PEMA in the blend. Mechanical properties including the tensile strength and flexural modulus also were found to be related to the composition of the blend. © 1993 John Wiley & Sons, Inc. 相似文献
14.
Motif patterns consisting of sequences of intermixed solid and don’t-care characters have been introduced and studied in connection with pattern discovery problems of computational biology and other domains. In order to alleviate the exponential growth of such motifs, notions of maximal saturation and irredundancy have been formulated, whereby more or less compact subsets of the set of all motifs can be extracted, that are capable of expressing all others by suitable combinations. In this paper, we introduce the notion of maximal irredundant motifs in a two-dimensional array and develop initial properties and a combinatorial argument that poses a linear bound on the total number of such motifs. The remainder of the paper presents approaches to the discovery of irredundant motifs both by offline and incremental algorithms. 相似文献
15.
Andreas Goralczyk Sofya Savicheva Ramin Montazeri Simona Fine Fadoua Mayoussi Pang Zhu Kay Steffen Frederik Kotz-Helmer Dorothea Helmer Bastian E. Rapp 《Advanced Engineering Materials》2023,25(8):2201314
Superhydrophobic coatings are widely applicable, e.g., as self-cleaning surfaces or water–oil separation membranes, yet their wider usage is impeded due to costs of fabrication, size, or substrate limitation. Spray-coating is a versatile coating procedures and might offer a good solution for the fabrication of these superhydrophobic coatings, due to the fact that coatings can be fabricated on various materials in a simple, fast, and inexpensive manner. Most procedures rely on hybrid coatings of hydrophobized nanoparticles and a polymeric matrix, which have several drawbacks including the easy loss of nanoparticles and difficult waste handling. Here, the fabrication of the superhydrophobic material, called Fluoropor, for the first time, by spray-coating on various substrates including metals, tissues, concrete, and glass is presented. It is fabricated by spray-coating a mixture of a highly fluorinated monomer blended with porogens followed by photopolymerization. The superhydrophobicity of the material relies on the porous structure on the micro-/nanoscale across the bulk material and does not require any nanoparticles. Excellent self-cleaning ability of these coatings, resistance against thermal and abrasive impact, and their application as oil–water separation membranes are shown. This versatile applicability is highly promising for real-world application as self-cleaning coatings or oil–water separating membranes. 相似文献
16.
Elena Piacenza Simona Campora Francesco Carfì Pavia Delia Francesca Chillura Martino Vito Armando Laudicina Rosa Alduina Raymond Joseph Turner Davide Zannoni Alessandro Presentato 《International journal of molecular sciences》2022,23(20)
The intense use of tellurium (Te) in industrial applications, along with the improper disposal of Te-derivatives, is causing their accumulation in the environment, where oxyanion tellurite (TeO32−) is the most soluble, bioavailable, and toxic Te-species. On the other hand, tellurium is a rare metalloid element whose natural supply will end shortly with possible economic and technological effects. Thus, Te-containing waste represents the source from which Te should be recycled and recovered. Among the explored strategies, the microbial TeO32− biotransformation into less toxic Te-species is the most appropriate concerning the circular economy. Actinomycetes are ideal candidates in environmental biotechnology. However, their exploration in TeO32− biotransformation is scarce due to limited knowledge regarding oxyanion microbial processing. Here, this gap was filled by investigating the cell tolerance, adaptation, and response to TeO32− of a Micromonospora strain isolated from a metal(loid)-rich environment. To this aim, an integrated biological, physical-chemical, and statistical approach combining physiological and biochemical assays with confocal or scanning electron (SEM) microscopy and Fourier-transform infrared spectroscopy in attenuated total reflectance mode (ATR-FTIR) was designed. Micromonospora cells exposed to TeO32− under different physiological states revealed a series of striking cell responses, such as cell morphology changes, extracellular polymeric substance production, cell membrane damages and modifications, oxidative stress burst, protein aggregation and phosphorylation, and superoxide dismutase induction. These results highlight this Micromonospora strain as an asset for biotechnological purposes. 相似文献
17.
Oana Baldasici Loredana Balacescu Daniel Cruceriu Andrei Roman Carmen Lisencu Bogdan Fetica Simona Visan Andrei Cismaru Ancuta Jurj Lucian Barbu-Tudoran Valentina Pileczki Laurian Vlase Oana Tudoran Ovidiu Balacescu 《International journal of molecular sciences》2022,23(20)
Neo-adjuvant therapy (NAT) is increasingly used in the clinic for the treatment of breast cancer (BC). Pathological response to NAT has been associated with improved patients’ survival; however, the current techniques employed for assessing the tumor response have significant limitations. Small EVs (sEVs)-encapsulated miRNAs have emerged as promising new biomarkers for diagnosis and prediction. Therefore, our study aims to explore the predictive value of these miRNAs for the pathological response to NAT in BC. By employing bioinformatic tools, we selected a set of miRNAs and evaluated their expression in plasma sEVs and BC biopsies. Twelve miRNAs were identified in sEVs, of which, miR-21-5p, 221-3p, 146a-5p and 26a-5p were significantly associated with the Miller–Payne (MP) pathological response to NAT. Moreover, miR-21-5p, 146a-5p, 26a-5p and miR-24-3p were independent as predictors of MP response to NAT. However, the expression of these miRNAs showed no correlation between sEVs and tissue samples, indicating that the mechanisms of miRNA sorting into sEVs still needs to be elucidated. Functional analysis of miRNA target genes and drug interactions revealed that candidate miRNAs and their targets, can be regulated by different NAT regimens. This evidence supports their role in governing the patients’ therapy response and highlights their potential use as prediction biomarkers. 相似文献
18.
Claudia Riccardi Federica DAria Dominga Fasano Filomena Anna Digilio Maria Rosaria Carillo Jussara Amato Laura De Rosa Simona Paladino Mariarosa Anna Beatrice Melone Daniela Montesarchio Concetta Giancola 《International journal of molecular sciences》2022,23(20)
Two analogues of the MS3 aptamer, which was previously shown to have an exquisite capability to selectively bind and modulate the activity of mutant huntingtin (mHTT), have been here designed and evaluated in their physicochemical and biological properties. Featured by a distinctive propensity to form complex G-quadruplex structures, including large multimeric aggregates, the original 36-mer MS3 has been truncated to give a 33-mer (here named MS3-33) and a 17-mer (here named MS3-17). A combined use of different techniques (UV, CD, DSC, gel electrophoresis) allowed a detailed physicochemical characterization of these novel G-quadruplex-forming aptamers, tested in vitro on SH-SY5Y cells and in vivo on a Drosophila Huntington’s disease model, in which these shorter MS3-derived oligonucleotides proved to have improved bioactivity in comparison with the parent aptamer. 相似文献
19.
Silvia Pomella Antonella Porrazzo Matteo Cassandri Simona Camero Silvia Codenotti Luisa Milazzo Francesca Vulcano Giovanni Barillari Giovanni Cenci Cinzia Marchese Alessandro Fanzani Francesca Megiorni Rossella Rota Francesco Marampon 《International journal of molecular sciences》2022,23(21)
Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of childhood and adolescence that includes FP-RMS, harboring the fusion oncoprotein PAX3/7-FOXO1 and FN-RMS, often mutant in the RAS pathway. Risk stratifications of RMS patients determine different prognostic groups and related therapeutic treatment. Current multimodal therapeutic strategies involve surgery, chemotherapy (CHT) and radiotherapy (RT), but despite the deeper knowledge of response mechanisms underpinning CHT treatment and the technological improvements that characterize RT, local failures and recurrence frequently occur. This review sums up the RMS classification and the management of RMS patients, with special attention to RT treatment and possible radiosensitizing strategies for RMS tumors. Indeed, RMS radioresistance is a clinical problem and further studies aimed at dissecting radioresistant molecular mechanisms are needed to identify specific targets to hit, thus improving RT-induced cytotoxicity. 相似文献
20.
Maria Antonietta Grignano Stefania Bruno Simona Viglio Maria Antonietta Avanzini Marta Tapparo Marina Ramus Stefania Croce Chiara Valsecchi Eleonora Francesca Pattonieri Gabriele Ceccarelli Federica Manzoni Annalia Asti Carmelo Libetta Vincenzo Sepe Paolo Iadarola Marilena Gregorini Teresa Rampino 《International journal of molecular sciences》2022,23(18)
We propose a new organ-conditioning strategy based on mesenchymal stromal cell (MSCs)/extracellular vesicle (EVs) delivery during hypothermic perfusion. MSCs/EVs marker CD73 is present on renal proximal tubular cells, and it protects against renal ischemia-reperfusion injury by converting adenosine monophosphate into adenosine (ADO). In this study, after checking if CD73-silenced EVs (EVsi) would impact in vitro tubular-cell proliferation, we perfused kidneys of a rat model of donation after circulatory death, with Belzer solution (BS) alone, BS supplemented with MSCs, EVs, or EVsi. The ADO and ATP levels were measured in the effluents and tissues. Global renal ischemic damage score (GRS), and tubular cell proliferation index (IPT) were evaluated in the tissue. EVsi did not induce cell proliferation in vitro. Ex vivo kidneys perfused with BS or BS + EVsi showed the worst GRS and higher effluent ADO levels than the MSC- and EV-perfused kidneys. In the EV-perfused kidneys, the tissue and effluent ATP levels and IPT were the highest, but not if CD73 was silenced. Tissue ATP content was positively correlated with tissue ADO content and negatively correlated with effluent ADO level in all groups. In conclusion, kidney conditioning with EVs protects against ischemic damage by activating the CD73/ADO system. 相似文献