Search results for "platinum"
showing 10 items of 629 documents
A solution study of complex formation between iron(III) and oxalate in dimethylsulphoxide
1991
The complex formation between iron(III) and oxalic acid (ethanedioic acid, H2ox) has been studied by potentiometry in dimethylsulphoxide (dmso) solution. H2ox behaves as a weak diprotic acid in such a solvent, with overall association constants: log βj1=8.551(3) and log βj2=14.242(3) at 25°C and 0.1 Mn-Bu4NClO4. A reliable set of overall stability constants for the iron(III)-oxalato complexes, log β11=13.16(4), log β12=23.66(4) and log β13=30.75(4), have been obtained for the first time under identical conditions. The electrochemical behaviour of such complexes was studied in dmso at a platinum electrode. The coordination ability of oxalate towards iron(III) in dmso and water media is compa…
Weekly oxaliplatin, high-dose folinic acid and 24h-5-fluorouracil (FUFOX) as salvage therapy in metastatic colorectal cancer patients pretreated with…
2002
Irinotecan (CPT-11), oxaliplatin (OXA) and different folinic acid (FA) modulated 5-fluorouracil (5-FU) regimens are active as first-and second-line chemotherapy of metastatic colorectal cancer. However, the best palliative sequence of these substances is still unclear. After CPT-11 containing regimens the optimal salvage protocol has not yet been defined. Here, we retrospectively analysed the weekly ambulant combination of OXA with continuous FA/5-FU (FUFOX) after two different CPT-11 containing chemotherapeutic regimens. Patients: During October 1999 and May 2001, 20 patients (median 62; 48-74 years) were included who had disease progression after CPT-11/bolus FA/5-FU (Saltz; 7 patients, g…
Enhanced bistability by guest inclusion in Fe(ii) spin crossover porous coordination polymers
2012
Inclusion of thiourea guest molecules in the tridimensional spin crossover porous coordination polymers {[Fe(pyrazine)[M(CN)(4)]} (M = Pd, Pt) leads to novel clathrates exhibiting unprecedented large thermal hysteresis loops of ca. 60 K wide centered near room temperature.
New heteronuclear gold(I)-platinum(II) complexes with cytotoxic properties: are two metals better than one?
2014
A series of mono- and heterodinuclear gold(I) and platinum(II) complexes with a new bipyridylamine-phosphine ligand have been synthesized and characterized. The X-ray structures of the ligand precursor 4-iodo-N,N-di(pyridin-2-yl)benzamide, and of one gold derivative are reported. All the complexes display antiproliferative properties in vitro in human cancer cells in the range of cisplatin or higher, which appear to correlate with compounds' uptake. Interestingly, studies of the interactions of the compounds with models of DNA indicate different mechanisms of actions with respect to cisplatin. The biological activity study of these complexes provides useful information about the interest of…
New light on an old debate: does the RCN–PtCl2 bond include any back-donation? RCN←PtCl2 backbonding vs. the IR νCN blue-shift dichotomy in organoni…
2019
For a series of organonitrile [RCN (R = Me, CF3, Ph, CH3Ph, CF3Ph)] ligands, the nature of the N–Pt bond in the related cis-/trans-(RCN)2PtCl2 complexes has been computationally investigated by Density Functional Theory. A fragment based bond analysis has been performed in the canonical Kohn–Sham molecular orbitals framework, and it has been ultimately assessed that this bond is characterized both by N→Pt σ and by N←Pt π contributions. Voronoi Deformation Density charges further confirms the occurrence of N←Pt π interactions. Moreover, the Energy Decomposition Analysis-Natural Orbital for Chemical Valence (EDA-NOCV) method shows that the strength of the N←Pt π interaction is not negligible …
Voltammetric determinations of platinum and rhodium in particulate of Palermo (Italy) area
2012
Traffic has an important impact on the air quality which affects both the environmental and human health. Since the introduction of PGE-containing catalytic converters, a number studies have been undertaken to determine the effects of PGE emissions on human and to environment. This requires the development of good analytic methods to measure Pt and Rh concentrations in environmental matrices, as well to estimate background concentrations. In this paper are presented the results concerning Pt and Rh concentrations in PM10 samples collected at five stations within the urban area of Palermo. The highest mean values (Pt= 13 pg/m3, Rh=9.8 pg/m3) were recorded at an urban station, and the lowest …
Bevacizumab efficacy in metastatic colorectal cancer is dependent on primary tumor resection.
2014
Purpose Bevacizumab plus fluoropyrimidine-based chemotherapy is standard treatment for first-line and second-line metastatic colorectal cancer (mCRC). However, to date, there is no current biomarker predictive for the benefit of bevacizumab use for these patients. Preclinical data suggest that the presence of the primary tumor could be involved in less efficient antitumor activity of antiangiogenic agents, but no clinical data currently support this hypothesis. Methods We performed a retrospective analysis of factors associated with overall survival (OS) in a study cohort of 409 mCRC patients. Univariate and multivariate Cox proportional hazard regression models were used to assess the infl…
TRIPLET SCHEDULE OF WEEKLY 5-FLUOROURACIL AND ALTERNATING IRINOTECAN OR OXALIPLATIN IN ADVANCED COLORECTAL CANCER: A DOSE-FINDING AND PHASE II STUDY.
2010
A weekly administration of alternating irinotecan or oxaliplatin associated to 5-Fluorouracil in advanced colorectal cancer was planned in order to evaluate a new schedule maintaining dose intensities of each drug as in double combinations and tolerability of the triplet association. The following weekly schedule was administered: irinotecan, days 1 and 15; oxaliplatin, days 8 and 22; 5-fluorouracil (5-FU) over 12-h (from 10:00 p.m. to 10:00 a.m.) timed flat infusion, days 1-2, 8-9, 15-16 and 22-23, every 4 weeks. Dose- finding and phase II study were planned. Thirteen patients were enrolled in the dose-finding study and 23 in the phase II study. The recommended doses of our study are: irin…
Primary endpoint results of the OMEGA Study: One-year clinical outcomes after implantation of a novel platinum chromium bare metal stent.
2014
Bare metal stents (BMS) have similar rates of death and myocardial infarction (MI) compared to drug-eluting stents (DES). DES lower repeat revascularization rates compared to BMS, but may have higher rates of late stent thrombosis (ST) potentially due to impaired endothelialization requiring longer dual anti-platelet therapy (DAPT). OMEGA evaluated a novel BMS designed to have improved deliverability and radiopacity, in comparison to currently available platforms.OMEGA was a prospective, multicenter, single-arm study enrolling 328 patients at 37 sites (US and Europe). Patients received the OMEGA stent (bare platinum chromium element stent) for the treatment of de novo native coronary artery…
FIRST EXAMPLES OF DISELENO TWEEZER-LIKE LIGANDS: SYNTHESIS, CHARACTERIZATION AND Pt(II) CYCLOMETALATION
2000
Abstract The synthesis of the first examples of diseleno tweezer-like molecules is described starting from diselenocyanobenzenic or pyridinic compounds and chloronaphthyl or anthryl derivatives. The new diselenides are characterized by mass spectrometry and multinuclear NMR spectroscopy. Starting from naphthyl derivatives, it was unambigously demonstrated for the first time their cyclometalation with Pt(II) to form metalloreceptors.