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The European Physical Journal E - Motivated by the recent experimental findings by Kumar et al. (Phys. Rev. E., 82, 011701 (2010)) in which the inverse Fréedericksz transition is observed, we... 相似文献
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Paolo Marchini Giuseppe Trapani Gaetano Liso Vincenza Berardi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):309-314
Abstract The title compounds (4b-d) together with the benzothiazolines (5b-d) have been obtained by a reaction between 2,2′-dithiodianiline (1) and β-keto esters (2b-d). The reaction between 1 and the β-keto ester 2a gives 1,4-benzothiazine 3a in addition to the benzothiazoline 5a. It has been established that the 1,4-benzothaizines 4b-d undergo an acid-catalysed thermal rearrangement involving a [1,3] shift of the sulfur atom, giving rise to the isomeric 1,4-benzothiazines 3b-d. 相似文献
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Ptaquiloside, a potent carcinogen present in bracken fern, a plant consumed by farm animals, may be detected in traces by converting it into the bromopterosine. A simple synthesis of bromopterosine d2, to be used as standard in GC/MS or LC/MS analyses, is described. 相似文献
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Emanuela Fabiola Craparo Barbara Porsio Nicol Mauro Gaetano Giammona Gennara Cavallaro 《Macromolecular rapid communications》2015,36(15):1409-1415
Here, the synthesis and the characterization of novel amphiphilic graft copolymers with tunable properties, useful in obtaining polymeric fluorescent nanoparticles for application in imaging, are described. These copolymers are obtained by chemical conjugation of rhodamine B (RhB) moieties, polylactic acid (PLA), and O‐(2‐aminoethyl)‐O′‐methyl poly(ethylene glycol) (PEG) on α,β‐poly(N‐2‐hydroxyethyl)‐d,l ‐aspartamide (PHEA). In particular, PHEA is first functionalized with RhB to obtain PHEA–RhB with a derivatization degree in RhB (DDRhB) equal to 0.55 mol%. By varying the reaction conditions, different amounts of PLA are grafted on PHEA–RhB to obtain PHEA‐RhB‐PLA with DDPLA equal to 1.9, 4.0, and 6.2 mol%. Then, PEG chains are grafted on PHEA‐RhB‐PLA derivatives to obtain PHEA‐RhB‐PLA‐PEG graft copolymers. The preparation of polymeric fluorescent nanoparticles with tunable properties and spherical shape is described by using PHEA‐RhB‐PLA‐PEG with DD in PLA and PEG equal to 4.0 and 4.9 mol%, by following easily scaling up processes, such as emulsion‐solvent evaporation and high pressure homogenization (HPH)‐solvent evaporation techniques.
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Gennara Cavallaro Carla Sardo Emanuela Fabiola Craparo Gaetano Giammona 《Molecules (Basel, Switzerland)》2021,26(6)
Here, a novel strategy of formulating efficient polymeric carriers based on the already described INU-IMI-DETA for gene material whose structural, functional, and biological properties can be modulated and improved was successfully investigated. In particular, two novel derivatives of INU-IMI-DETA graft copolymer were synthesized by chemical functionalisation with epidermal growth factor (EGF) or polyethylenglycol (PEG), named INU-IMI-DETA-EGF and INU-IMI-DETA-PEG, respectively, in order to improve the performance of already described “inulin complex nanoaggregates” (ICONs). The latter were thus prepared by appropriately mixing the two copolymers, by varying each component from 0 to 100 wt% on the total mixture, named EP-ICONs. It was seen that the ability of the INU-IMI-DETA-EGF/INU-IMI-DETA-PEG polymeric mixture to complex siGL3 increases with the increase in the EGF-based component in the EP-ICONs and, for each sample, with the increase in the copolymer:siRNA weight ratio (R). On the other hand, the susceptibility of loaded siRNA towards RNase decreases with the increase in the pegylated component in the polymeric mixture. At all R values, the average size and the zeta potential values are suitable for escaping from the RES system and suitable for prolonged intravenous circulation. By means of biological characterisation, it was shown that MCF-7 cells are able to internalize mainly the siRNA-loaded into EGF-decorated complexes, with a significant difference from ICONs, confirming its targeting function. The targeting effect of EGF on EP-ICONs was further demonstrated by a competitive cell uptake study, i.e., after cell pre-treatment with EGF. Finally, it was shown that the complexes containing both EGF and PEG are capable of promoting the internalisation and therefore the transfection of siSUR, a siRNA acting against surviving mRNA, and to increase the sensitivity to an anticancer agent, such as doxorubicin. 相似文献
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Gaetano Isola Alessandro Polizzi Vincenzo Ronsivalle Angela Alibrandi Giuseppe Palazzo Antonino Lo Giudice 《Molecules (Basel, Switzerland)》2021,26(6)
Matrix metalloproteinase-9 (MMP-9) has been shown to play a key role in endothelial function and perhaps pivotal in the correlation between periodontal disease and cardiovascular disease (CVD). For the study, the impact of MMP-9 of periodontitis and CVD on serum and saliva concentrations was analyzed. For the study patients with periodontitis (n = 31), CVD (n = 31), periodontitis + CVD (n = 31), and healthy patients (n = 31) were enrolled. Clinical and demographic characteristics as well as serum and salivary MMP-9 were evaluated. MMP-9 concentrations in serum and saliva were statistically elevated in patients with CVD (p < 0.01) and in patients with periodontitis plus CVD (p < 0.001) compared to patients with periodontitis and healthy subjects. Multivariate regression analysis showed that c-reactive protein (hs-CRP) was the only significant predictor for MMP-9 serum (p < 0.001), whereas hs-CRP (p < 0.001) and total cholesterol (p = 0.029) were the statistically significant salivary MMP-9 predictors. This study evidenced that patients with CVD and periodontitis + CVD presented elevated MMP-9 concentrations in serum and saliva compared to patients with periodontitis and healthy subjects. Furthermore, hs-CRP was a negative predictor of serum and salivary MMP-9. 相似文献
30.
We analyze light self-confinement induced by multiple nonlinear resonances in a two-dimensional chi(2) photonic crystal. With reference to second-harmonic generation in a hexagonal lattice, we show that the system can not only support two-color (1+1)D solitary waves with enhanced confinement and steering capabilities but also enable novel features such as wavelength-dependent soliton routing. 相似文献