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1.
Notti A Occhipinti S Pappalardo S Parisi MF Pisagatti I White AJ Williams DJ 《The Journal of organic chemistry》2002,67(21):7569-7572
Synthesis and single-crystal X-ray structures of mixed triple and double calixarenes 6 and 7, obtained from the base-catalyzed condensation of calix[5]arene 1 with cone pertosylated calix[4]arene 2, are reported. VT-NMR studies on 7 are consistent with a molecular motion arising from the anti-gauche conformational interconversion of its ethylene linkages. 相似文献
2.
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
3.
Alpha-1-antitrypsin (AAT) and alpha-1-acid glycoprotein (AAG) are reported to be the main proteins contributing to the alpha-1-globulin capillary zone electrophoresis (CZE) zone, but the sum (AAT + AAG) showed lower than the alpha-1-globulin. We investigated the role of high-density lipoprotein (HDL), an additional protein migrating in the alpha-1-globulin zone, as a possible cause for such a gap. In a set of 98 sera we measured the alpha-1-globulin with a dedicated clinical capillary electrophoresis system, and AAT, AAG and apolipoprotein A-1 (ApoA) by immunonephelometry. The alpha-1-globulin were consistently higher than the sum (AAT + AAG), by (mean value +/- standard deviation) 1.70 +/- 0.88 g/L in 49 sera with low ApoA, and by 3.59 +/- 0.75 g/L in 49 sera with high ApoA. Corresponding figures in the comparison alpha-1-globulin/(AAT + AAG + ApoA) were reduced to 1.08 +/- 0.77 g/L and 1.67 +/- 0.70 g/L. It is concluded that HDL significantly contribute to the CZE alpha-1-globulin zone, but do not completely explain the differences between the electrophoretic and the immunochemical measurements. However, CZE alpha-1-globulin measurements give information about increases of the two major acute phase proteins comparable to specific protein measurements. 相似文献
4.
Giuseppe Gattuso Sebastiano Pappalardo Melchiorre F. Parisi Ilenia Pisagatti 《Supramolecular chemistry》2014,26(7-8):597-600
The molecular recognition in water of neurotransmitter monoamine and trace amine hydrochlorides by p-tert-butylcalix[5]-arene 1 – bearing 4-sulphonatobutoxy groups at the lower rim – has been investigated. According to 1H NMR measurements, the hydrophobic cavity of receptor 1 best binds tyramine hydrochloride, Ka = 5370 ± 870 M? 1. 相似文献
5.
A Petrov-Galerkin finite element method is presented for calculation of the steady, axisymmetric thermosolutal convection and interface morphology in a model for vertical Bridgman crystal growth of nondilute binary alloys. The Petrov-Galerkin method is based on the formulation for biquadratic elements developed by Heinrich and Zienkiewicz and is introduced into the calculation of the velocity, temperature and concentration fields. The algebraic system is solved simultaneously for the field variables and interface shape by Newton's method. The results of the Petrov-Galerkin method are compared critically with those of Galerkin's method using the same finite element grids. Significant improvements in accuracy are found with the Petrov-Galerkin method only when the mesh is refined and when the formulation of the residual equations is modified to account for the mixed boundary conditions that arise at the solidification interface. Calculations for alloys with stable and unstable solute gradients show the occurrence of classical flow transitions and morphological instabilities in the solidification system. 相似文献
6.
Ilenia Infusino Cristina Valente Alberto Dolci Mauro Panteghini 《Analytical and bioanalytical chemistry》2010,397(2):521-525
The purpose of measurement standardization is to achieve closer comparability of results obtained using different commercial
systems. Regarding serum protein immunoassays, a reference preparation (BCR-470) was released in 1993 and adopted by manufacturers
across the world to value-assign their assay calibrators for routine methods to reduce method-dependent variation. Moving
from nephelometric (Beckman Immage 800) to turbidimetric determination (Roche Cobas c 501) of seven serum proteins, we preliminarily
checked the comparability of results between the two systems. The study was performed according to the CLSI EP9-A protocol
on 30 fresh sera, tested on each system in duplicate, and subdivided on two different days, without recalibration and using
manufacturers’ control materials to validate the runs. Both manufacturers’ package inserts provide statements that kit calibrators
are traceable to BCR-470. Suggested reference intervals are also the same. Although a fairly good correlation was observed
(r = 0.955), the comparison of ceruloplasmin methods produced evidence of highly significant proportional (regression slope,
0.572) and constant bias (intercept, 0.05 g/L). Absolute and percentage mean differences were −0.11 g/L (95% confidence interval
(CI) −0.13 to −0.10 g/L) and −39.1% (CI −43.1 to −35.2%), respectively. No other evaluated proteins showed similar problems.
Lacking a ceruloplasmin reference method, it is impossible to demonstrate that one of the two assays produces true ceruloplasmin
values. The problem is, however, that results coming from the two assays are clearly not comparable. This may be either due
to a lack of commutability of the reference material with biological samples in the evaluated assays or to calibration problems
by manufacturers in one of the stages of the calibration hierarchy. 相似文献
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8.
Antonino Lauria Ilenia Abbate Noemi Gambino Giampaolo Barone 《Tetrahedron letters》2008,49(35):5125-5128
Derivatives of the new ring system pyrazolo[3,4-d][1,2,3]triazolo[1,5-a]pyrimidine were synthesized from the corresponding angular isomers, through a Dimroth rearrangement, in quantitative yields. Preliminary computational studies demonstrated that this class of compounds could be a good candidate as DNA intercalating agents. 相似文献
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10.
Stefano DUGHERI Nicola MUCCI Ilenia POMPILIO Giovanni CAPPELLI Costanza BOSSI Alessandro BONARI Giulio ARCANGELI 《色谱》2018,36(12):1311-1322
Long-term indoor-air limit for formaldehyde stipulated by the European Commission is 1 μg/m3,while the World Health Organization has set a threshold of 100 μg/m3 that should not be exceeded for more than 30 min. To date,however,only a few analytical techniques have been developed that can be used to detect formaldehyde at these very restrictive limits. Thus,there is a need to develop for comprehensive methods for analyzing airborne formaldehyde and other carbonyl pollutants in the ambient environment. The aim of this study is to develop a highly sensitive online automated preconcentration gas chromatographic method using large-volume injection with a programmed temperature vaporization injector for the analysis of airborne formaldehyde and ten other carbonyl compounds. The influence of several parameters,such as the maximum volume injected,programmed temperature vaporization transfer time and temperature,carrier gas flow rate,and type of packing material was investigated. After optimization,highly satisfactory results in terms of the absolute and methodological detection limits were achieved,i. e. as low as the μg/m3 level for all the carbonyl pollutants studied. A commercially available sampler,originally designed for active sampling,was evaluated as a passive sampling device;this optimized technique was applied to monitor the concentrations of carbonyl pollutants in the indoor air of ten public buildings in Florence. The strength of this methodology lies both in the low detection limits reached in the simultaneous analysis of a wide group of 2,4-dinitrophenylhydrazine derivatives,and the potential adaptability of this method to other gas chromatographic applications to achieve lower sensitivity. 相似文献