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101.
Mügge C Rothenburger C Beyer A Görls H Gabbiani C Casini A Michelucci E Landini I Nobili S Mini E Messori L Weigand W 《Dalton transactions (Cambridge, England : 2003)》2011,40(9):2006-2016
Twelve Pt(II) complexes with cis-PtP(2)S(2) pharmacophores (where P(2) refers to two monodentate or one bidentate phosphane ligand and S(2) is a dithiolato ligand) were prepared, characterized and evaluated as potential antiproliferative agents. The various compounds were first studied from the structural point of view; afterward, their solubility properties as well as their solution behaviour were analyzed in detail. Antiproliferative properties were specifically evaluated against A2780 human ovarian carcinoma cells, either resistant or sensitive to cisplatin. For comparison purposes similar studies were carried out on four parent cis-dichloro bisphosphane Pt(II)complexes. On the whole, the cis-PtP(2)S(2) compounds displayed significant antiproliferative properties while the cis-PtP(2)Cl(2) (cis-dichloro bisphosphane Pt(II)) compounds revealed quite poor biological performances. To gain further insight into the molecular mechanisms of these bisphosphane Pt(II) compounds, the reactions of selected complexes against the model protein cytochrome c were investigated by ESI-MS and their adduct formation explored. A relevant reactivity with cyt c was obtained only for cis-PtP(2)Cl(2) compounds, whereas cis-PtP(2)S(2) compounds turned out to be nearly unreactive. The obtained results are interpreted and discussed in the frame of the current knowledge of anticancer platinum compounds and their structure-activity-relationships. The observation of appreciable antiproliferative effects for the relatively inert cis-PtP(2)S(2) compounds strongly suggests that these compounds will undergo specific activation within the cellular environment. 相似文献
102.
Mola J Dinoi C Sala X Rodríguez M Romero I Parella T Fontrodona X Llobet A 《Dalton transactions (Cambridge, England : 2003)》2011,40(14):3640-3646
The bis(2-pyridyl)ethylamine (bpea) ligand has been used as a starting material for the synthesis of dinuclear Ru complexes of general formula trans,fac-{[Ru(n)X(bpea)](2)(μ-bpp)}(m+) (for X = Cl, n = II, m = 1, trans-Ru(II)-Cl, 1(+); for X = OH, n = III, m = 3, trans-Ru(III)-OH, 2(3+)) where the 3,5-bis(2-pyridyl)pyrazolate anionic ligand (bpp) acts as bridging dinucleating ligand, the bpea ligand coordinates in a facial manner and the monodentate ligands X are situated in a trans fashion with regard to one another. These complexes have been characterized in solution by 1D and 2D NMR spectroscopy, UV-vis and electrochemical techniques and in the solid state by X-ray diffraction analysis. The reaction of 1(PF(6)) with Ag(+) generates the corresponding solvated complex where the Cl ligand has been removed as insoluble AgCl, followed by the oxidation of Ru(II) to Ru(III) to generate the corresponding dinuclear complex trans-Ru(III)-OH, 2(PF(6))(3). The latter has been shown to catalytically oxidize water to molecular dioxygen using Ce(IV) as oxidant. Quantitative gas evolution as a function of time has been monitored on line by both manometry and mass spectroscopy (MS) techniques. Relative initial velocities of oxygen formation together with structural considerations rule out an intramolecular O-O bond formation pathway. 相似文献
103.
Nagy EM Nardon C Giovagnini L Marchiò L Trevisan A Fregona D 《Dalton transactions (Cambridge, England : 2003)》2011,40(44):11885-11895
During the last decade, our research group has prepared a number of metal dithiocarbamato derivatives of Pt, Pd and Au that were expected to resemble the main features of cisplatin together with higher activity, improved selectivity and bioavailability, and lower side-effects. Furthermore, we have already published the synthesis, characterization and in vitro cytotoxicity studies of novel ruthenium(III) dithiocarbamato complexes such as [RuL(3)] monomers (11) and α-[Ru(2)L(5)]Cl dimers (12) with five different dithiocarbamate ligands. As both the monomer and the dinuclear complexes have shown significant antitumor activity in different human tumor cell lines, we decided to widen the characterization studies and to analyse thoroughly their behavior in physiological-like medium by UV-visible and CD spectroscopy. In the present paper we report on the crystal structure of [Ru(DMDT)(3)], [Ru(PDT)(3)] and [Ru(ESDT)(3)] complexes and we determine the spin state of the paramagnetic Ru(III) by means of Evans' method. Then, we discuss in detail the UV-visible spectral data of the complexes in different medium. All the studied complexes are stable in dimethyl sulfoxide, and show low solubility in phosphate buffered saline solution, particularly the monomer species, even at low concentration, while increased solubility for both types of complexes have been found in the presence of bovine serum albumin (BSA). Moreover, no changes on the coordination sphere of the metal, as well as no direct interaction between the BSA protein and the complex have been identified by UV-visible spectroscopy. However, some conformational changes on the BSA structure, induced by the ruthenium(III) complexes have been confirmed by CD spectroscopy, indicating a probable secondary electrostatic interaction between the metal complex and the peptide. In addition, no significant interaction has been demonstrated with the components of Dulbecco's Modified Eagle's Medium, used for the in vitro assays. 相似文献
104.
Chiono V Sartori S Rechichi A Tonda-Turo C Vozzi G Vozzi F D'Acunto M Salvadori C Dini F Barsotti G Carlucci F Burchielli S Nicolino S Audisio C Perroteau I Giusti P Ciardelli G 《Macromolecular bioscience》2011,11(2):245-256
A biocompatible and elastomeric PU was synthesized from low-molecular-weight PCL as macrodiol, CMD as chain extender and HDI as chain linker for applications in the field of peripheral nerve repair. PU cast films supported in vitro attachment and proliferation of NOBEC. The in vitro adhesion and proliferation of S5Y5 neuroblastoma cells on the inner surface of uncoated, gelatin- and PL-coated PU guides were compared. Due to their superior in vitro performance, PL-coated PU guides were tested in vivo for the repair of 1.8 cm-long defects in rat sciatic nerves. The progressive regeneration was confirmed by EMG and histological analysis showing the presence of regenerating fibers in the distal stumps. 相似文献
105.
Euterpio MA Cavaliere C Capriotti AL Crescenzi C 《Analytical and bioanalytical chemistry》2011,401(9):2977-2985
Pressurized hot water extraction (PHWE, also known as subcritical water extraction) is commonly considered to be an environmentally
friendly extraction technique that could potentially replace traditional methods that use organic solvents. Unfortunately,
the applicability of this technique is often limited by the very low water solubility of the target compounds, even at high
temperatures. In this paper, the scope for broadening the applicability of PHWE by adjusting the pH of the water used in the
extraction is demonstrated in the extraction of curcumin (which exhibits very limited water solubility) from untreated turmeric
(Curcuma longa L.) rhizomes. Although poor extraction yields were obtained, even at high temperatures when using degassed water or neutral
phosphate buffer as the extraction medium, yields exceeding those obtained by Soxhlet extraction were achieved using highly
acidic pH buffers due to curcumin protonation. The influence of the temperature, pH, and buffer concentration on the extraction
yield were investigated in detail by means of a series of designed experiments. Optimized conditions for the extraction of
curcumin from turmeric by PHWE were estimated at 197 °C using 62 g/L buffer concentration at pH 1.6. The relationships between
these variables were subjected to statistical analysis using response surface methodology. 相似文献
106.
Capriotti AL Caracciolo G Cavaliere C Crescenzi C Pozzi D Laganà A 《Analytical and bioanalytical chemistry》2011,401(4):1195-1202
The knowledge about the interaction between plasma proteins and nanocarriers employed for in vivo delivery is fundamental
to understand their biodistribution. Protein adsorption onto nanoparticle surface (protein corona) is strongly affected by
vector surface characteristics. In general, the primary interaction is thought to be electrostatic, thus surface charge of
carrier is supposed to play a central role in protein adsorption. Because protein corona composition can be critical in modifying
the interactive surface that is recognized by cells, characterizing its formation onto lipid particles may serve as a fundamental
predictive model for the in vivo efficiency of a lipidic vector. In the present work, protein coronas adsorbed onto three
differently charged cationic liposome formulations were compared by a shotgun proteomic approach based on nano-liquid chromatography–high-resolution
mass spectrometry. About 130 proteins were identified in each corona, with only small differences between the different cationic
liposome formulations. However, this study could be useful for the future controlled design of colloidal drug carriers and
possibly in the controlled creation of biocompatible surfaces of other devices that come into contact with proteins into body
fluids. 相似文献
107.
Theoretical modeling has been applied to study the charge transport (CT) parameters of a high-electron-mobility (n-type) naphthalenetetracarboxydiimide copolymer that was recently synthesized and tested for organic field-effect transistor applications. To understand the physicochemical characteristics of such a material, the intra- and intermolecular CT properties of holes and electrons were investigated using different DFT functionals, evidencing the need of range-separated hybrid functionals to predict key parameters such as the hole and electron reorganization energies. Our calculations revealed clear differences between hole- and electron-charging processes, providing fundamental elements for the rationalization of their transport. 相似文献
108.
Micieli D Giuffrida MC Pignatello R Castelli F Sarpietro MG 《Journal of colloid and interface science》2011,360(2):359-369
Anti-inflammatory drugs represent a potential new strategy for the treatment of Alzheimer's disease (AD). The ability to cross the blood-brain barrier and to reach brain tissues is a critical point for these drugs and is strictly related to their lipophilicity. Naproxen (NAP) is a non-steroidal anti-inflammatory drug (NSAIDs) under active investigation for AD. To improve its lipophilic character, NAP was conjugated through a diethylamine spacer (EDA) to lipoamino acids (LAA), α-amino acids containing a long alkyl side chain, to obtain the NAP-EDA-LAA10 and NAP-EDA-LAA14 prodrugs. The interaction of NAP and prodrugs with dimyristoylphosphatidylcholine phospholipids, forming either multilamellar vesicles or monolayers (at the air/water interface) and used as biomembrane models, was studied by differential scanning calorimetry and Langmuir-Blodgett techniques. Experimental data showed that NAP conjugation with LAA residues was able to enhance the drug interaction with such biomembrane models. 相似文献
109.
Harikumar KR McNab IR Polanyi JC Zabet-Khosousi A Panosetti C Hofer WA 《Chemical communications (Cambridge, England)》2011,47(44):12101-12103
Chloropentane forms asymmetric ('A') and symmetric ('S') pairs on Si(100)-2×1, differing in the direction of curvature of one pentane tail. Surprisingly this renders the rate of thermal reaction of 'A' fifteen times greater than 'S' in chlorinating room-temperature silicon. Correspondingly, for electron-induced reaction the energy threshold for A is 1 eV less than for S. 相似文献
110.
Efficient crystallization induced emissive materials based on a simple push-pull molecular structure
Cariati E Lanzeni V Tordin E Ugo R Botta C Schieroni AG Sironi A Pasini D 《Physical chemistry chemical physics : PCCP》2011,13(40):18005-18014
Solid state luminescent materials are the subject of ever growing interest both from a scientific and a technological point of view. Aggregation caused quenching (ACQ) processes however represent an obstacle to the development of most luminogens in the condensed phase. This is why particularly fascinating are those materials showing higher emission intensity in the solid state than in solution. Here we report on three 4-dialkylamino-2-benzylidene malonic acid dialkyl esters, very simple push-pull molecules, which are hardly emissive in solution and in the amorphous phase but become good emitters in the crystalline phase according to what has been indicated as crystallization induced emission (CIE). Thanks to combined emission and NMR spectroscopies at different temperatures on the prototype compound 4-dimethylamino-2-benzylidene malonic acid dimethyl ester in solution, we give full evidence that a restricted intramolecular rotation (RIR) phenomenon, in particular the hindered rotation around the aryl main axis of the compound, is at the origin of this behaviour. In addition, solid state photophysical and X-ray diffraction structural characterization allow us to identify J-dimeric interactions as responsible for the particularly intense emission of two of the three compounds. Moreover, by exploiting the compounds' acidochromic properties, applications in sensors and optoelectronics are envisaged. 相似文献