55 research outputs found
Are public and private social expenditures complementary?
Most analyses of social protection are focussed on public arrangements. However, social effort is not
restricted to the public domain; all kinds of private arrangements can be substitutes to public programs.
OECD-data indicate that accounting for private social benefits and the impact of the tax system on social
expenditure has an equalising effect on levels of social effort across a number of countries. This suggests
complementarity between public and private social expenditures. Changes in the public/private mix in
social protection will, however, have distributional effects. We expect that private schemes will generate
less income redistribution than public programs.
In this paper we will perform an empirical analysis. Using comparative international data we analyse
whether there is a relationship between public and private social expenditures, and the distribution of
income. We find a negative relationship between net public social expenditures and income inequality, but
a positive relationship between net private social expenditures and income inequality across countries. In
fact, when we incorporate private social security expenditures, the impact of total social expenditure on
the income distribution becomes statistically trivial. We conclude that changes in the public/private mix in
the provision of social protection may affect the redistributive impact of the welfare state
Cisplatin-DNA adduct formation in patients treated with cisplatin-based chemoradiation: lack of correlation between normal tissues and primary tumor
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69595.pdf (publisher's version ) (Closed access)PURPOSE: In this study, the formation of cisplatin-DNA adducts after concurrent cisplatin-radiation and the relationship between adduct-formation in primary tumor tissue and normal tissue were investigated. METHODS: Three intravenous cisplatin-regimens, given concurrently with radiation, were studied: daily low-dose (6 mg/m(2)) cisplatin, weekly 40 mg/m(2), three-weekly 100 mg/m(2). A (32)P-postlabeling technique was used to quantify adducts in normal tissue [white blood cells (WBC) and buccal cells] and tumor. RESULTS: Normal tissue samples for adduct determination were obtained from 63 patients and tumor biopsies from 23 of these patients. Linear relationships and high correlations were observed between the levels of two guanosine- and adenosine-guanosine-adducts in normal and tumor tissue. Adduct levels in tumors were two to five times higher than those in WBC (P<0.001). No significant correlations were found between adduct levels in normal tissues and primary tumor biopsies, nor between WBC and buccal cells. CONCLUSIONS: In concurrent chemoradiotherapy schedules, cisplatin adduct levels in tumors were significantly higher than in normal tissues (WBC). No evidence of a correlation was found between adduct levels in normal tissues and primary tumor biopsies. This lack of correlation may, to some extent, explain the inconsistencies in the literature regarding whether or not cisplatin-DNA adducts can be used as a predictive test in anticancer platinum therapy
Busulphan is active against neuroblastoma and medulloblastoma xenografts in athymic mice at clinically achievable plasma drug concentrations
High-dose busulphan-containing chemotherapy regimens have shown high response rates in children with relapsed or refractory neuroblastoma, Ewing's sarcoma and medulloblastoma. However, the anti-tumour activity of busulfan as a single agent remains to be defined, and this was evaluated in athymic mice bearing advanced stage subcutaneous paediatric solid tumour xenografts. Because busulphan is highly insoluble in water, the use of several vehicles for enteral and parenteral administration was first investigated in terms of pharmacokinetics and toxicity. The highest bioavailability was obtained with busulphan in DMSO administered i.p. When busulphan was suspended in carboxymethylcellulose and given orally or i.p., the bioavailability was poor. Then, in the therapeutic experiments, busulphan in DMSO was administered i.p. on days 0 and 4. At the maximum tolerated total dose (50 mg kg−1), busulphan induced a significant tumour growth delay, ranging from 12 to 34 days in the three neuroblastomas evaluated and in one out of three medulloblastomas. At a dose level above the maximum tolerated dose, busulphan induced complete and partial tumour regressions. Busulphan was inactive in a peripheral primitive neuroectodermal tumour (PNET) xenograft. When busulphan pharmacokinetics in mice and humans were considered, the estimated systemic exposure at the therapeutically active dose in mice (113 μg h ml−1) was close to the mean total systemic exposure in children receiving high-dose busulphan (102.4 μg h ml−1). In conclusion, busulphan displayed a significant anti-tumour activity in neuroblastoma and medulloblastoma xenografts at plasma drug concentrations which can be achieved clinically in children receiving high-dose busulphan-containing regimens. 1999 Cancer Research Campaig
Structure of a stacked anthraquinone-DNA complex
The crystal structure of the telomeric sequence d(UBrAGG) interacting with an anthraquinone derivative has been solved by MAD. In all previously studied complexes of intercalating drugs, the drug is usually sandwiched between two DNA base pairs. Instead, the present structure looks like a crystal of stacked anthraquinone molecules in which isolated base pairs are intercalated. Unusual base pairs are present in the structure, such as G·G and A·UBr reverse Watson-Crick base pairs. © 2010 International Union of Crystallography All rights reserved.We acknowledge support from the European Project MPRN-CT-2000-00009 and from the Ministerio de Ciencia e Innovación, project No. BFU 2009-10380.Peer Reviewe
A Rapid, Universal TI-59 Model-Independent Pharmacokinetic Analysis Program based on Statistical Moment Theory
A cubic arrangement of DNA double helices based on nickel-guanine interactions
DNA oligonucleotides can be used in order to assemble highly structured materials. Oligonucleotides with sticky ends can form long linear structures, whereas branching is required to form two- and three-dimensional nanostructures. In this paper, we show that when Ni2+ is attached to the N7 atom of guanine, it can also act as a branching point. Thus, we have found that the heptanucleotide d(GAATTCG) can assemble into long linear duplex structures, which cross in space to generate a cubic structure. The three-dimensional arrays are stabilized by phosphate-Ni2+-guanine interactions. For the first time, the crystallization of a B form DNA oligonucleotide in a cubic system is reported, space group /23. Large solvent cavities are found among the DNA duplexes.One of us (N.V.) acknowledges a fellowship from the Generalitat de Catalunya. This work has been supported by Grants BI2002-00317 from the Ministerio de Ciencia y TecnologÃa and 2001 SGR 00250 from the Generalitat de CatalunyaPeer Reviewe
Development of bisphosphonates controlled delivery systems for bone implantation: influence of the formulation and process used on in vitro release
The present study investigates the development of controlled drug delivery devices by association of bisphosphonates (BPs) with calcium-deficient apatite (CDA) to obtain a prolonged drug delivery. In a first part, we studied the microencapsulation of methylene bisphosphonic acid, our model of BPs, in biodegradable PLGA by the double emulsion (w/o/w) solvent evaporation/extraction process. Secondly, we associated BPs, either in a free form or microencapsulated, with calcium phosphate biomaterials. The association of free BPs with CDA was performed by isostatic compression at 80 MPa and we tested the interest of adding a binder, HPMC, in the formulation to reinforce the association. In parallel, microparticles were associated with calcium-deficient apatite, either by simple mixture or by isostatic compression. To compare the different formulations, in vitro dissolution studies were performed. All the formulations tested appear to be efficient to produce BPs loaded biomaterials able to deliver the drug slowly and at a constant rate. The slowest release rate (2.7% in 14 days) was obtained with the blend of microencapsulated BPs with CDA
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Homogeneous Escherichia coli FPG protein. A DNA glycosylase which excises imidazole ring-opened purines and nicks DNA at apurinic/apyrimidinic sites.
The repair of 2,6-diamino-4-hydroxy-5-N-methyl-formamidopyrimidine (Fapy) residues in DNA is performed by a Fapy-DNA glycosylase activity which is encoded for by the fpg gene in Escherichia coli. Besides DNA glycosylase activity, this protein, the FPG protein, is endowed with an EDTA-resistant activity nicking DNA at apurinic/apyrimidinic (AP) sites. To overproduce the FPG protein, the fpg gene was placed under the control of the tac promoter in the expression vector pKK223-3 yielding the pFPG230 plasmid. The production of the FPG protein in cells harboring the pFPG230 plasmid was 800-fold higher than that of the wild type strain after induction by isopropyl-beta-D-thio-galactopyranoside. From these cells, the FPG protein was purified to homogeneity in sufficient quantity to study its physical and catalytic properties. In its active form, the FPG protein is a globular monomer of 31 kDa and has an experimentally measured isoelectric point of 8.5. When the FPG protein is heat-denatured in the presence of EDTA the two activities are more rapidly inactivated than when heated in the absence of EDTA, suggesting that the FPG protein possesses a tightly bound metal ion. Atomic absorption spectrophotometric analysis shows that there is one zinc/FPG protein molecule. The FPG protein is different from previously described DNA glycosylases and AP-nicking enzymes in E. coli. The contribution of the AP-nicking activity associated with the FPG protein represents 10-20% of the total EDTA-resistant AP-nicking activities in E. coli
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