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141.
Irina Ielciu Mihaela Niculae Emoke Pall Cristina Barblat Ioan Tomu Neli-Kinga Olah Ramona Flavia Burtescu Daniela Benedec Ilioara Oniga Daniela Hanganu 《Molecules (Basel, Switzerland)》2022,27(13)
Rosmarinus officinalis L. is a species that is widely known for its culinary and medicinal uses. The purpose of the present study consisted of the evaluation of the antiproliferative and antimicrobial effects of R. officinalis-loaded liposomes (L-R). Characterization of the liposomes was performed by establishing specific parameters. The load of the obtained liposomes was analyzed using an LC-MS method, and antiproliferative assays evaluated the cell viability on a liver adenocarcinoma cell line and on a human hepatic stellate cell line. Antimicrobial assays were performed by agar–well diffusion and by broth microdilution assays. The obtained liposomes showed high encapsulation efficiency, suitable particle size, and good stability. High amounts of caffeic (81.07 ± 0.76), chlorogenic (14.10 ± 0.12), carnosic (20.03 ± 0.16), rosmarinic (39.81 ± 0.35), and ellagic (880.02 ± 0.14) acids were found in their composition, together with other polyphenols. Viability and apoptosis assays showed an intense effect on the cancerous cell line and a totally different pattern on the normal cells, indicating a selective toxicity towards the cancerous ones and an anti-proliferative mechanism. Antimicrobial potential was noticed against all tested bacteria, with a better efficacy towards Gram-positive species. These results further confirm the biological activities of R. officinalis leaf extract, and proposes and characterizes novel delivery systems for their encapsulation, enhancing the biological activities of polyphenols, and overcoming their limitations. 相似文献
142.
Fedor Gmry Daniela Bettinelli Laura Gherardi Giovanni Crotti 《Physica C: Superconductivity and its Applications》1998,310(1-4):48-51
Magnetic nature of the losses in superconducting wire carrying AC current implies that it should be possible to determine these losses in a contactless way. Ribbon-like samples are quite favorable for such an experiment, because a notable portion of magnetic flux related to losses ‘escapes' the sample volume and can be detected by an appropriate pick-up coil. In this case, a model describing the AC current penetration into the tape, based, e.g., on the critical state model, allows one to derive the losses from the pick-up coil signal. Because this signal is proportional to the number of coil turns, extension of the accessible range of measured voltages (and losses) can be achieved. We demonstrate the data obtained on a 1 cm long portion of a low-loss multifilamentary tape carrying AC current with frequency 35 Hz. The pick-up coil technique allowed us to reach loss level more than one order below the experimental limit for direct measurements. 相似文献
143.
A. Baldan Adriaan M. H. van der Veen Daniela Prauß Angelika Recknagel N. Boley Steve Evans Derek Woods 《Accreditation and quality assurance》2001,6(4-5):164-167
Many proficiency tests are operated with a consensus value derived from the participants’ results. Apart from technical issues,
one of the reasons often mentioned is that proficiency tests operated with consensus values would be cheaper than those using
reference values obtained from a priori characterisation measurements. The economy of a proficiency test must of course be balanced by the need of the participants,
and the quality of the comparison in general. The proficiency tests selected in this study had both a reference value and
a consensus value, one of which was used for assessing the performance of the participating laboratories. In this work, both
a technical and an economical assessment of how the comparisons were operated is made. From the evaluation, it follows that
usually the use of consensus values does not necessarily reduce the costs of a proficiency test. However, frequently it may
be observed that the quality of the assessment of the laboratories is better with a reference value.
Received: 11 October 2000 Accepted: 3 January 2001 相似文献
144.
Jeanine Giarolla Daniela G. Rando Kerly F.M. Pasqualoto Márcio H. Zaim Elizabeth I. Ferreira 《Journal of Molecular Structure》2010,939(1-3):133-138
Molecular modeling methodologies were applied to perform preliminary studies concerning the release of active agents from potentially antichagasic and antileishmanial dendrimer prodrugs. The dendrimer was designed having myo-inositol as a core, l-malic acid as a spacer group, and hydroxymethylnitrofurazone (NFOH), 3-hydroxyflavone or quercetin, as active compounds. Each dendrimer presented a particular behavior concerning to the following investigated properties: spatial hindrance, map of electrostatic potential (MEP), and the lowest unoccupied molecular orbital energy (ELUMO). Additionally, the findings suggested that the carbonyl group next to the active agent seems to be the most promising ester breaking point. 相似文献
145.
Pietro Franceschi Roland Thissen Odile Dutuit Christian Alcaraz Heloise Soldi-Lose Davide Bassi Daniela Ascenzi Paolo Tosi Jan Zabka Zdenek Herman Marcello Coreno Monica de Simone 《International journal of mass spectrometry》2009,280(1-3):119
The long-lived excited states of doubly charged rare gases can markedly affect their reactivity. In this paper we demonstrate the presence of strong state-specific effects in the charge exchange of Ar2+ (3P, 1D and 1S) with several neutral targets (He, Ne, Kr, Xe, D2, and CH4). State sensitive measurements have been performed by producing the different Ar2+ electronic states via tunable synchrotron radiation (Elettra-Trieste, Italy and SuperACO-Orsay, France). From the product ion yield data of charge transfer, state-selected total cross-sections have been deduced. Using the state-specific reactivity of Ar2+ towards different neutral targets, it has been possible to extract the photon-energy-dependent production branching of the three doubly charged states and to investigate the autoionization dynamics of neutral or singly charged Ar in the vicinity of the double ionization threshold. 相似文献
146.
Riccardo Ricceri Alessandro Abbotto Antonio Facchetti Daniela Grando Gabriella Gabrielli Giorgio A. Pagani 《Colloids and surfaces. A, Physicochemical and engineering aspects》1999,150(1-3):289-296
We report on Langmuir-Blodgett (LB) films characterization of 4-[5-dicyanomethanido)thien-2-y1]-N-(n-hexadecyl)pyridinium (C16H33-PDCNT), and 1-(N-(n-hexadecy]-4-pyridinio)-2-[5-(dicyanomethanido)thien-2-yl]ethene (C16H33-PDCNTE); LB films of the pure compounds and of the mixtures of the two compounds were prepared at 291 K: UV-vis investigation revealed the presence of photobleachable absorption bands, the ones at about 530 nm and 640 nm were due to charge transfer transitions of the monomer of C16H33-PDCNT and C16H33-PDCNTE, respectively; the sharp, photobleachable ones shifted to shorter wavelengths were due to H-aggregates of the two compounds. By changing the molar ratios of the two compounds in the mixtures and in other cases by annealing the LB films, the absorption maxima of the sharp, photobleachable bands due to H-aggregates could be tuned in the range 415–467 nm. These LB films are thus very promising in view of optical data storage applications. 相似文献
147.
148.
Daniela Kraus 《Journal of Mathematical Analysis and Applications》2008,345(2):628-631
The precise asymptotic behaviour of the solutions to the two-dimensional curvature equation Δu=k(z)e2u with e2u∈L1 for bounded nonnegative curvature functions −k(z) near isolated singularities is obtained. 相似文献
149.
Monica Magureanu Daniela Piroi Florin Gherendi Nicolae Bogdan Mandache Vasile Parvulescu 《Plasma Chemistry and Plasma Processing》2008,28(6):677-688
The decomposition of methylene blue (MB) in aqueous solution was investigated using a pulsed corona discharge. The discharge
was ignited in the gas bubbled in the solution through several needle electrodes. The influence of treatment time, volume
of the treated solution and initial concentration of the dye in solution on MB degradation was studied. The effect of the
nature of the gas introduced was also investigated. For the same energy input, MB conversion increased in the order air < argon < oxygen.
When using oxygen, the decomposition of MB exceeded 95% after ~20 min plasma treatment. Higher efficiency was obtained for
higher treated volume and higher initial concentration. At 90% conversion the yield obtained with oxygen was ~5 g/kWh for
an initial concentration of 150 mg/l and a treated volume of solution of 100 ml. 相似文献
150.
Daniele Passarella Sergio Riva Gabriele Grieco Francesco Cavallo Begoña Checa Federica Arioli Elena Riva Daniela Comi Bruno Danieli 《Tetrahedron: Asymmetry》2009,20(2):192-197
The convenient synthesis of both enantiomers of the piperidine alkaloids such as dumetorine and epidihydropinidine is described. Pure enantiomers of 2-(2-hydroxy-ethyl)-piperidine-1-carboxylic acid tert-butyl ester are used as a common starting material. The syntheses are based on a RCM reaction and on methylation of the piperidine ring according to Beak–Lee methodology, respectively. 相似文献