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61.
Fontana A Viale M Guernelli S Gasbarri C Rizzato E Maccagno M Petrillo G Aiello C Ferrini S Spinelli D 《Organic & biomolecular chemistry》2010,8(24):5674-5681
Different nitronaphthylbutadienes have been previously proved to have antitumour activity. The main drawback of these derivatives is their low water solubility. With the aim of facilitating the administration of these new drugs we have synthesized the hexyl (2Z,4E)-2-methylsulfanyl-5-(1-naphthyl)-4-nitro-2,4-pentadienoate analogue (1-Naph-NHCB) which is demonstrated to be easily included into cyclodextrins and/or entrapped into liposomes. Its antitumour activity was revealed to be almost comparable with that of the previously studied methyl analogue ester (1-Naph-NMCB). On the other hand, in vitro studies with different cancer cell lines showed that the cytotoxic activity of both 1-Naph-NMCB and 1-Naph-NHCB were fully preserved and in some cases also enhanced when entrapped into liposomal carriers. 相似文献
62.
Silvia Canepari Elisabetta Marconi Maria Luisa Astolfi Cinzia Perrino 《Analytical and bioanalytical chemistry》2010,397(6):2533-2542
A quick and reliable analytical method for the separation and quantification of extractable Sb(III) and Sb(V) in atmospheric
particulate matter (PM) by ion chromatography(IC)-inductively coupled plasma-mass spectrometry (ICP-MS) has been optimized,
validated on pairs of real, equivalent PM10 samples and applied to a field monitoring campaign in a urban site. Both Sb(III) and Sb(V) forms were detected in real samples
with Sb(III)/Sb(V) ratios up to 1.5. These two Sb species accounts only for a portion, of variable magnitude, of the total
extractable Sb (10–70%); anyway, no other soluble Sb species were detected in the samples. The analysis of size-segregated
samples collected by a 13-stage impactor showed that the recovery of [Sb(III) + Sb(V)] versus total extractable Sb is almost
quantitative in the coarse fraction while it is below than 10% in the fine fraction. In the extracted solution from particles
below 1 μm we could highlight the presence of Sb-containing suspended solid nano-particles, which probably constitute the
missing fraction. The contribution of nano-particles can be estimated as the difference between ICP-MS and IC-ICP-MS data,
as small size solid bodies are able to pass through the nebulizer and reach the plasma torch, while they are retained by the
chromatographic column. The aggregation state of these nano-particles seems to be easily altered when they are suspended in
a water solution; a similar behavior could be hypothesized when in contact with biological fluids. It has been confirmed that
brake pad abrasion is the prevalent source of Sb(III) in PM and that Sb(V) may be formed by oxidation during the braking processes.
Differing from other environmental matrices, there is no evidence of any spontaneous oxidative conversion within the two species. 相似文献
63.
64.
Patrizia Restani Cinzia Ballabio Chiara Di Lorenzo Salvatore Tripodi Alessandro Fiocchi 《Analytical and bioanalytical chemistry》2009,395(1):47-56
Milk allergy is the most frequent food allergy in childhood. Even though cases of newly developed milk allergy in adulthood
are known, this allergy is less frequent in adults since it is normally outgrown by children during the first years of life.
One of the reasons why allergy to cow’s milk shows its highest prevalence in children is its early introduction into the diets
of babies when breast feeding is not possible. The major allergens are caseins and β-lactoglobulin, but allergies to other
minor proteins (immunoglobulins, bovine serum albumin) have also been reported. Milk allergenicity can be reduced by various
treatments (mainly hydrolysis), meaning that formulas based on cow’s milk can often be safely fed to children allergic to
milk proteins. Cross-reactivity has been described between different mammalian milks and between milk and meat or animal dander.
Cross-contamination can result from inadequate cleaning of industrial equipment and constitutes a hidden danger for allergic
subjects who unknowingly ingest milk proteins.
Figure Involvement (expressed as percentage of total subjects) of the most abundant milk proteins in the sensitization of 80 children
allergic to cow’s milk. The upper panel includes all positive responses, even minor ones; data in the lower panel are restricted to the most severe positive responses (see text for details). SPT, skin prick test; CAP, CAP test; IMM, immunoblotting; alpha-LA, α-lactalbumin; beta-LG, β-lactoglobulin; cas, caseins; BSA, bovine serum albumin 相似文献
65.
Here, we report the evaluation of the molecular recognition properties of a small library of pyrimethanil-imprinted pellicular beads prepared in the presence of several co-monomers of decreasing hydrophobicity, namely N-methacrylamidopiperidine, methylmethacrylate, N-methacrylamidopyrrolidine, N-vinylpyrrolidone, 2-hydroxyethylmethacrylate, acrylonitrile, N-methacrylamidomorpholine, and N,N-dimethylacrylamide. The effect of the presence of these co-monomers on the molecular recognition properties of the beads were studied by eluting the pyrimethanil/Sudan Orange G pair, in the presence of acetonitrile/water mobile phases of increasing polarity. The pyrimethanil was used to probe the specific interactions due to the presence of binding sites. The Sudan Orange G (that is greatly different from the template but with comparable hydrophobicity and molecular mass) was instead used to probe the non-specific interactions due to the bulk of the polymer. The experimental results show that the polymers prepared in the presence of polar co-monomers are characterised by a marked increase of the analytes retention if compared with the imprinted polymer prepared without these co-monomers. The increase of retention is more pronounced for pyrimethanil compared to Sudan Orange G with polymers prepared in the presence of the more hydrophilic co-monomers N-vinylpyrrolidone, acrylonitrile and N-methacrylamidomorpholine, while N,N-dimethylacrylamide is the only co-monomer that does not significantly influence the retention of analytes. Increasing the amount of water in the mobile phase progressively diminishes this effect. 相似文献
66.
Anna Lisa Piccinelli Cinzia Lotti Lorella Severino Diomira Luongo Luca Rastrelli 《Tetrahedron》2008,64(23):5449-5453
Two new sulfated cadinene-type sesquiterpene glycosides, 13-hydroxy-7-O-(6′-O-sulfate-β-d-glucopyranosyl)-desoxyhemigossypol (1) and 13,15-dihydroxy-7-O-(6′-O-sulfate-β-d-glucopyranosyl)-desoxyhemigossypol (2), have been isolated from whole cottonseed (Gossypium hirsutum). Their structures, which possess an unusual 6-O-sulfate-glucopyranosyl moiety, were determined through the interpretation of 2D NMR spectral data and H/D exchange ESI-MS experiments. Compounds 1 and 2 were screened for their toxicity on Jurkat cells. Both compounds inhibited cellular proliferation with IC50 values of 8.1 and 4.2 μg, respectively. 相似文献
67.
68.
A Palladium‐Catalyzed Carbonylation Approach to Eight‐Membered Lactam Derivatives with Antitumor Activity 下载免费PDF全文
Dr. Raffaella Mancuso Dr. Dnyaneshwar S. Raut Dr. Nadia Marino Dr. Giorgio De Luca Dr. Cinzia Giordano Prof. Dr. Stefania Catalano Dr. Ines Barone Prof. Dr. Sebastiano Andò Prof. Dr. Bartolo Gabriele 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(9):3053-3064
The reactivity of 2‐(2‐alkynylphenoxy)anilines under PdI2/KI‐catalyzed oxidative carbonylation conditions has been studied. Although a different reaction pathway could have been operating, N‐palladation followed by CO insertion was the favored pathway with all substrates tested, including those containing an internal or terminal triple bond. This led to the formation of a carbamoylpalladium species, the fate of which, as predicted by theoretical calculations, strongly depended on the nature of the substituent on the triple bond. In particular, 8‐endo‐dig cyclization preferentially occurred when the triple bond was terminal, leading to the formation of carbonylated ζ‐lactam derivatives, the structures of which have been confirmed by XRD analysis. These novel medium‐sized heterocyclic compounds showed antitumor activity against both estrogen receptor‐positive (MCF‐7) and triple negative (MDA‐MB‐231) breast cancer cell lines. In particular, ζ‐lactam 3 j′ may represent a novel and promising antitumor agent because biological tests clearly demonstrate that this compound significantly reduces cell viability and motility in both MCF‐7 and MDA‐MB‐231 breast cancer cell lines, without affecting normal breast epithelial cell viability. 相似文献
69.
Dimesityldiclorosilane undergoes reductive coupling with potassium-graphite to afford a mixture of cyclic polysilanes in a high yield and purity; this mixture is quantitatively converted to the title compound by photochemical irradiation. 相似文献
70.