992 resultados para Delayed-Action Preparations
Resumo:
Purpose: To examine whether the levels of micronuclei induction, as a marker for genomic instability in the progeny of X-irradiated cells, correlates with DNA repair function.
Materials and methods: Two repair deficient cell lines (X-ray repair cross-complementing 1 [XRCC1] deficient cell line [EM9] and X-ray repair cross complementing 5 [XRCC5; Ku80] deficient X-ray sensitive Chinese hamster ovary [CHO] cell line [xrs5]) were used in addition to wild-type CHO cells. These cells were irradiated with low doses of X-rays (up to 1 Gy). Seven days after irradiation, micronuclei formed in binucleated cells were counted. To assess the contribution of the bystander effect micronuclei induction was measured in progeny of non-irradiated cells co-cultured with cells that had been irradiated with 1Gy.
Results: The delayed induction of micronuclei in 1 Gy-irradiated cells was observed in normal CHO and EM9 but not in xrs5. In the clone analysis, progenies of xrs5 under bystander conditions showed significantly higher levels of micronuclei, while CHO and EM9 did not.
Conclusion: Genomic instability induced by X-irradiation is associated with DSB (double-strand break) repair, even at low doses. It is also suggested that bystander signals, which lead to genomic instability, may be enhanced when DSB repair is compromised.
Resumo:
This article uses the example of Northern Ireland to illustrate how political mobilization may
be deployed to challenge structural forms of inequality. The experience suggests that regulatory
models can be designed for particular contexts to shape approaches that present challenges to
dominant economic and political orthodoxies. The intention is not to overstate the significance
of this specific transitional context but simply to highlight elements that might feature in any
attempt to mobilize successfully around human rights and equality, and against aspects of neoliberal
thinking.
Resumo:
Biofilm growth on stone surfaces is a significant contributing factor to stone biodeterioration. Current market based biocides are hazardous to the environment and to public health. We have investigated the photo-dynamic effect of methylene blue (MB) in the presence of hydrogen peroxide (H2O2) on the destruction of the cyanobacterium Synechococcus leopoliensis (S. leopoliensis) under irradiation with visible light. Data presented in this paper illustrate that illumination of S. leopoliensis in the presence of a photosensitiser (MB) and H2O2 results in the decomposition of both the cyanobacterium and the photosensitiser. The presence of MB and H2O2 affects the viability of the photosensitiser and the cyanobacterium with the fluorescence of both decreasing by 80% over the irradiation time investigated. The photo-dynamic effect was observed under aerobic and anaerobic conditions indicating that oxygen was not necessary for the process. This novel combination could be effective for the remediation of biofilm colonised stone surfaces
Resumo:
Monoglycated cholecystokinin octapeptide (Asp(1)-glucitol CCK-X) was prepared under hyperglycaemic reducing conditions and purified by reverse phase-high performance liquid chromatography. Electrospray ionisation mass spectrometry and automated Edman degradation demonstrated that CCK-8 was glycated specifically at the amino-terminal Asp(1) residue. Effects of Asp(1)-glucitol CCK-8 and CCK-8 on insulin secretion were examined using glucose-responsive clonal BRIN-BD11 cells. In acute (20 min) incubations, 10(-10) mol/l CCK-8 enhanced insulin release by 1.2-1.5-fold at 5.6-11.1 mmol/l glucose. The stimulatory effect induced by 10(-10) mom CCK-8 was abolished following glycation. At 5.6 mmol/l glucose, CCK-8 at concentrations ranging from 10(-11) to 10(-7) mol/l induced a significant 1.6-1.9-fold increase in insulin secretion. Insulin output in the presence of Asp(1)-glucitol CCK-8 over the concentration range 10(-11)-10(-7) mol/l was decreased by 21-35% compared with CCK-8, and its insulinotropic action was effectively abolished. Asp(1)-glucitol CCK-8 at 10(-8) mol/l also completely blocked the stimulatory effects of 10(-11)-10(-8) mol/l CCK-8. These data indicate that structural modification by glycation at the amino-terminal Asp(1) residue effectively abolishes and/or antagonises the insulinotropic activity of CCK-8. (C) 1999 Elsevier Science B.V. All rights reserved.
Resumo:
This paper, which was published as a chapter of a Festskrift for Professor Ruth Nielsen, analyses Article 23 CFREU, the new provision on gender equality. It argues that Article 23 adds to the notion of gender equality in EU law, and not only allows, but also demands positive action measures if necessary to ensure equality between women and men. The provision also demands that positive action measures are suitable to achieve their aim. This implies that the EU legislator has to adapt positive action measure to the specific needs of the sector. The paper offers a critique of the proposal to introduce women quotas in board rooms, as proposed by the EU Commission in late 2012. It argues that the Commission unimaginatively copied rules developed for the German public service into a different sector, although these rules have not proven particularly efficient even in the public service. Consequently, a proposal that is demanding, but adapted to the sector should be developed.