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71.
72.
Annali di Matematica Pura ed Applicata (1923 -) - We obtain convolution inequalities in Lebesgue and Lorentz spaces with power weights when the functions involved are assumed to be radially... 相似文献
73.
Ellen Fast Dr. Alexander Schlimm Irene Lautenschläger Kai Uwe Clausen Dr. Thomas Strunskus Carina Spormann Prof. Dr. Thisbe K. Lindhorst Prof. Dr. Felix Tuczek 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(2):485-501
Self-assembled monolayers (SAMs) decorated with photoisomerizable azobenzene glycosides are useful tools for investigating the effect of ligand orientation on carbohydrate recognition. However, photoswitching of SAMs between two specific states is characterized by a limited capacity. The goal of this study is the improvement of photoswitchable azobenzene glyco-SAMs. Different concepts, in particular self-dilution and rigid biaryl backbones, have been investigated. The required SH-functionalized azobenzene glycoconjugates were synthesized through a modular approach, and the respective glyco-SAMs were fabricated on Au(111). Their photoswitching properties have been extensively investigated by applying a powerful set of methods (IRRAS, XPS, and NEXAFS). Indeed, the combination of tailor-made biaryl-azobenzene glycosides and suitable diluent molecules led to photoswitchable glyco-SAMs with a significantly enhanced and unprecedented switching capacity. 相似文献
74.
Beatriz Lozano‐Torres Juan F. Blandez Irene Galiana Alba García‐Fernndez María Alfonso María D. Marcos Mar Orzez Flix Sancenn Ramn Martínez‐Mez 《Angewandte Chemie (International ed. in English)》2020,59(35):15152-15156
In vivo detection of cellular senescence is accomplished by using mesoporous silica nanoparticles loaded with the NIR‐FDA approved Nile blue (NB) dye and capped with a galactohexasaccharide ( S3 ). NB emission at 672 nm is highly quenched inside S3 , yet a remarkable emission enhancement is observed upon cap hydrolysis in the presence of β‐galactosidase and dye release. The efficacy of the probe to detect cellular senescence is tested in vitro in melanoma SK‐Mel‐103 and breast cancer 4T1 cells and in vivo in palbociclib‐treated BALB/cByJ mice bearing breast cancer tumor. 相似文献
75.
Luisa Pieroni Federica Iavarone Alessandra Olianas Viviana Greco Claudia Desiderio Claudia Martelli Barbara Manconi Maria Teresa Sanna Irene Messana Massimo Castagnola Tiziana Cabras 《Journal of separation science》2020,43(1):313-336
More than 300 different protein post‐translational modifications are currently known, but only a few have been extensively investigated because modified proteoforms are commonly present in sub‐stoichiometry amount. For this reason, improvement of specific enrichment techniques is particularly useful for the proteomic characterization of post‐translationally modified proteins. Enrichment proteomic strategies could help the researcher in the challenging issue to decipher the complex molecular cross‐talk existing between the different factors influencing the cellular pathways. In this review the state of art of the platforms applied for the enrichment of specific and most common post‐translational modifications, such as glycosylation and glycation, phosphorylation, sulfation, redox modifications (i.e. sulfydration and nitrosylation), methylation, acetylation, and ubiquitinylation, are described. Enrichments strategies applied to characterize less studied post‐translational modifications are also briefly discussed. 相似文献
76.
Francesca Di Cristo Anna Valentino Ilenia De Luca Gianfranco Peluso Irene Bonadies Anna Calarco Anna Di Salle 《Molecules (Basel, Switzerland)》2022,27(7)
The management of periodontitis remains a vital clinical challenge due to the interplay between the microorganisms of the dental biofilm and the host inflammatory response leading to a degenerative process in the surrounding tissues. Quercetin (QUE), a natural flavonol found in many foods, including apples, onions and tea, has exhibited prolonged and strong antibiofilm and anti-inflammatory effects both in vitro and in vivo. However, its clinical application is limited by its poor stability and water solubility, as well as its low bioavailability. Thus, in the present study, electrospun polylactic acid (PLA) nanofibers loaded with different amounts (5–10% w/w) of QUE were produced to rapidly respond to the acidic microenvironment typical of periodontal pockets during periodontal disease. This strategy demonstrated that PLA-QUE membranes can act as a drug reservoir releasing high QUE concentrations in the presence of oral bacterial infection (pH < 5.5), and thus limiting Pseudomonas aeruginosa PAO1 and Streptococcus mutans biofilm maturation. In addition, released QUE exerts antioxidant and anti-inflammatory effects on P. gingivalis Lipopolysaccharide (LPS)-stimulated human gingival fibroblast (HGFs). The reported results confirmed that PLA-QUE membranes could inhibit subgingival biofilm maturation while reducing interleukin release, thereby limiting host inflammatory response. Overall, this study provided an effective pH-sensitive drug delivery system as a promising strategy for treating periodontitis. 相似文献
77.
Paloma Begines Sergio Martos Irene Lagunes Ins Maya Jos M. Padrn
scar Lpez Jos G. Fernndez-Bolaos 《Molecules (Basel, Switzerland)》2022,27(4)
Being aware of the enormous biological potential of organoselenium and polyphenolic compounds, we have accomplished the preparation of novel hybrids, combining both pharmacophores in order to obtain new antioxidant and antiproliferative agents. Three different families have been accessed in a straightforward and chemoselective fashion: carbohydrate-containing N-acylisoselenoureas, N-arylisoselenocarbamates and N-arylselenocarbamates. The nature of the organoselenium framework, number and position of phenolic hydroxyl groups and substituents on the aromatic scaffolds afforded valuable structure–activity relationships for the biological assays accomplished: antioxidant properties (antiradical activity, DNA-protective effects, Glutathione peroxidase (GPx) mimicry) and antiproliferative activity. Regarding the antioxidant activity, selenocarbamates 24–27 behaved as excellent mimetics of GPx in the substoichiometric elimination of H2O2 as a Reactive Oxygen Species (ROS) model. Isoselenocarbamates and particularly their selenocarbamate isomers exhibited potent antiproliferative activity against non-small lung cell lines (A549, SW1573) in the low micromolar range, with similar potency to that shown by the chemotherapeutic agent cisplatin (cis-diaminodichloroplatin, CDDP) and occasionally with more potency than etoposide (VP-16). 相似文献
78.
Irene Scheunert 《Chemie in Unserer Zeit》1994,28(2):68-78
Im Prinzip kann fast jede organische Industriechemikalie durch die Mikroorganismen des Bodens abgebaut werden. 相似文献
79.
Michael Reinhardt Andreas Schnhals Dietmar Pfeifer Karl Pfeiffer Irene V. Lampe Hans-Joachim Lorkowski 《先进技术聚合物》1996,7(10):791-796
Dielectric relaxation spectroscopy in the frequency range from 10−2 Hz to 106 Hz and electron spin resonance (ESR) experiments are employed to study the dynamics in chemically and physically crosslinked networks. As examples for physically crosslinked networks ortho- and para-cresol novolacs were investigated. Dielectrically these materials show low-temperature β- and high-temperature α-relaxation. Both relaxation regions differ for both types of novolacs. This is also reflected by the ESR measurements and is discussed in terms of different hydrogen bonds found to be stronger in para-cresol novolac. For the chemically crosslinked poly(triallyl isocyanurate) only a β-peak is found by the dielectric measurements. Also in the ESR experiment the slow motion regime is characterized up to high temperatures. This means that the segmental motion is strongly suppressed by chemical crosslinking. Nevertheless the obtained change in the formal T50G value can be used to characterize the glass transition in highly crosslinked systems by the ESR method. 相似文献
80.
Gialiana Biagi Irene Giorgi Oreste Livi Valerio Scartoni Silvia Velo Pier Luigi Barili 《Journal of heterocyclic chemistry》1996,33(6):1847-1853
A new 4-(benzotriazol-1-yl)-1,2,3-triazole structure was obtained by the diazotization reaction of either of 1-(2-aminophenyl)-4-carboxamido-5-amino-1H-1,2,3-triazole ( 1c ) or of the corresponding Dimroth isomer 1d . It underwent some common reactions to evaluate its chemical behaviour and structure. An analogous reaction sequence was carried out from the 2-nitro-4-methylphenyl azide, to assign the structure to the nitro derivatives prepared. The structure of the new compounds prepared was confirmed by chemical and spectroscopic methods. 相似文献