The ratio of initial/residual DNA damage predicts intrinsic radiosensitivity in seven cervix carcinoma cell lines.

The single-cell gel electrophoresis (comet) assay was used to measure radiation-produced DNA double-strand breaks (dsbs) in a series of seven cervical tumour cell lines (ME180, HT3, C33A, C41, SiHa, MS751 and CaSki). The proportion of DNA dsbs was measured immediately after radiation treatment (initial damage) and 16 h later after incubation at 37 degrees C (residual damage). Linear dose-response curves were seen for initial (slopes 0.23-0.66) and residual (slopes 0.16-0.87) DNA dsbs. Neither of the slopes of the linear regression analysis on the initial and on the residual DNA dsbs dose-response curves (range 0-80 Gy) correlated with SF2 (surviving fraction at 2 Gy) measured after high- (HDR) or low-dose-rate (LDR) irradiation. An association was evident between SF2 after HDR and LDR irradiation and the ratio of the absolute level of initial and residual damage after a single dose of 60 Gy. However, a significant correlation was found between HDR (r= -0.78, P = 0.04) and LDR (r = -0.86, P = 0.03) SF2 values and the ratio of the slopes of the initial and residual DNA dsbs dose-response curves (range 0.47-0.99), representing the fraction of DNA damage remaining. These results indicate that the neutral comet assay can be used to predict radiosensitivity of cervical tumour cell lines by assessing the ratio of initial and residual DNA dsbs

A comet assay of DNA damage and repair in K562 cells after photodynamic therapy using haematoporphyrin derivative, methylene blue and meso-tetrahydroxyphenylchlorin.

Single-cell electrophoresis (comet assay) has been used to evaluate DNA damage and repair in the human myeloid leukaemia cell line K562 after low-dose (predominantly sub-lethal) treatments of hyperthermia and photodynamic therapy (PDT). Three different photosensitizers were examined: haematoporphyrin derivative (HpD), methylene blue (MB) and meso-tetrahydroxyphenylchlorin (mTHPC). None of the drugs in the absence of light, nor in light alone, resulted in detectable DNA damage. However, a significant amount of DNA damage was detected immediately after treatment with haematoporphyrin derivative or methylene blue PDT compared with drug-only or light-only treatments; no residual level of DNA damage was evident for either drug following a 4-h post-treatment incubation at 37 degrees C. No significant DNA damage was detected after meso-tetrahydroxyphenylchlorin PDT or hyperthermia either immediately or 4 h after treatment. We conclude that the alkaline comet assay can be applied as an effective screening assay for DNA damage induced by a range of laser therapies

Sebomic identification of sex- and ethnicity-specific variations in residual skin surface components (RSSC) for bio-monitoring or forensic applications

Background: “Residual skin surface components” (RSSC) is the collective term used for the superficial layer of sebum, residue of sweat, small quantities of intercellular lipids and components of natural moisturising factor present on the skin surface. Potential applications of RSSC include use as a sampling matrix for identifying biomarkers of disease, environmental exposure monitoring, and forensics (retrospective identification of exposure to toxic chemicals). However, it is essential to first define the composition of “normal” RSSC. Therefore, the aim of the current study was to characterise RSSC to determine commonalities and differences in RSSC composition in relation to sex and ethnicity. Methods: Samples of RSSC were acquired from volunteers using a previously validated method and analysed by high-pressure liquid chromatography–atmospheric pressure chemical ionisation–mass spectrometry (HPLC-APCI-MS). The resulting data underwent sebomic analysis. Results: The composition and abundance of RSSC components varied according to sex and ethnicity. The normalised abundance of free fatty acids, wax esters, diglycerides and triglycerides was significantly higher in males than females. Ethnicity-specific differences were observed in free fatty acids and a diglyceride. Conclusions: The HPLC-APCI-MS method developed in this study was successfully used to analyse the normal composition of RSSC. Compositional differences in the RSSC can be attributed to sex and ethnicity and may reflect underlying factors such as diet, hormonal levels and enzyme expression.Peer reviewedFinal Published versio

Aquaporin-1 Water Channel Expression in Human Kidney

The pattern of aquaporin-1 water channel protein (AQP1) expression in the human kidney was analyzed by immunocytochemistry using semi-thin and optimized high-resolution immunoelectron microscopy based on freeze-substituted and Lowicryl HM20 embedded tissue. In addition, in situ hybridization was used to determine AQP1 mRNA distribution. Immunoblots revealed a 28-kd band and a 35- to 45-kd band corresponding to unglycosylated and glycosylated AQP1. Glomerular capillary endothelium exhibited extensive AQP1 labeling, whereas glomerular podocytes and Bowman's capsule epithelium were unlabeled. AQP1 was localized in the proximal tubule, including the neck region directly connected to the glomerulus. However, there was a marked difference in the level of expression between cross-sections of the convoluted part and the proximal straight tubules, the latter displaying the most intense labeling. AQP1 labeling continued uninterrupted from the proximal straight tubule into descending thin limbs in outer medulla. Abrupt transitions from heavily labeled to unlabeled segments of thin limbs were observed, primarily in the inner medulla. This may represent the transition from the water-permeable thin descending limb to the water-impermeable thin ascending limb. In addition, heavy labeling of fenestrated endothelium was also observed in peritubular capillaries in cortex, outer medulla, and inner medulla. Immunolabeling controls were negative. In situ hybridization documented a marked difference in AQP1 mRNA levels within the proximal tubule, with the greatest AQP1 mRNA expression in straight proximal tubules. Glomeruli also showed marked signals, and descending thin limbs exhibited extensive expression in exact concordance with the immunocytochemical results. It was concluded that: (1) AQP1 is present in all proximal tubule segments, including segment 1 and the neck region, but there is a pronounced difference in expression levels with respect to both protein and mRNA levels; (2) AQP1 labeling is observed in the endothelium of fenestrated peritubular capillaries, as well as fenestrated glomerular capillaries; (3) AQP1 labeling continues directly from proximal tubules to descending thin limbs; and (4) abrupt transitions from labeled to unlabeled thin limb epithelium are noted

Cellular Radiosensitivity: How much better do we understand it?

Purpose: Ionizing radiation exposure gives rise to a variety of lesions in DNA that result in genetic instability and potentially tumorigenesis or cell death. Radiation extends its effects on DNA by direct interaction or by radiolysis of H2O that generates free radicals or aqueous electrons capable of interacting with and causing indirect damage to DNA. While the various lesions arising in DNA after radiation exposure can contribute to the mutagenising effects of this agent, the potentially most damaging lesion is the DNA double strand break (DSB) that contributes to genome instability and/or cell death. Thus in many cases failure to recognise and/or repair this lesion determines the radiosensitivity status of the cell. DNA repair mechanisms including homologous recombination (HR) and non-homologous end-joining (NHEJ) have evolved to protect cells against DNA DSB. Mutations in proteins that constitute these repair pathways are characterised by radiosensitivity and genome instability. Defects in a number of these proteins also give rise to genetic disorders that feature not only genetic instability but also immunodeficiency, cancer predisposition, neurodegeneration and other pathologies. Conclusions: In the past fifty years our understanding of the cellular response to radiation damage has advanced enormously with insight being gained from a wide range of approaches extending from more basic early studies to the sophisticated approaches used today. In this review we discuss our current understanding of the impact of radiation on the cell and the organism gained from the array of past and present studies and attempt to provide an explanation for what it is that determines the response to radiation

He Was not Alone: Bosman in Context

This chapter analyses the social, political, historical and economic context of the Bosman case. The chapter argues that Bosman needs to be understood as yet another stage of a continued process of commercialisation and transformation in European football. Football players fought to transform their employment conditions since the 1960s. Clubs questioned the legitimacy of UEFA to regulate European football and organise club competitions as they wanted a larger share of the commercial profits of the game. Finally, political institutions in Brussels started to exert pressure on football governing bodies to modify the international transfer system. The chapter argues that, taking these into account, major transformations in the governance and regulation structures of football were needed, and they would have happened even without the Bosman ruling. Consequently, Bosman cannot be seen, on its own, as the only cause of the transformation of modern football in Europe. Finally, the chapter dedicates some space to Jean Marc Bosman’s legal team composed by Luc Misson and Jean Louis Dupont. It was their legal expertise what made a challenge before the Belgian and European courts also possible

The clinical and economic benefits of capecitabine and tegafur with uracil in metastatic colorectal cancer

Two oral fluoropyrimidine therapies have been introduced for metastatic colorectal cancer. One is a 5-fluorouracil pro-drug, capecitabine; the other is a combination of tegafur and uracil administered together with leucovorin. The purpose of this study was to compare the clinical effectiveness and cost-effectiveness of these oral therapies against standard intravenous 5-fluorouracil regimens. A systematic literature review was conducted to assess the clinical effectiveness of the therapies and costs were calculated from the UK National Health Service perspective for drug acquisition, drug administration, and the treatment of adverse events. A cost-minimisation analysis was used; this assumes that the treatments are of equal efficacy, although direct randomised controlled trial (RCT) comparisons of the oral therapies with infusional 5-fluorouracil schedules were not available. The cost-minimisation analysis showed that treatment costs for a 12-week course of capecitabine (£2132) and tegafur with uracil (£3385) were lower than costs for the intravenous Mayo regimen (£3593) and infusional regimens on the de Gramont (£6255) and Modified de Gramont (£3485) schedules over the same treatment period. Oral therapies result in lower costs to the health service than intravenous therapies. Further research is needed to determine the relative clinical effectiveness of oral therapies vs infusional regimens

The ASAS-SN bright supernova catalogue - III. 2016

This catalogue summarizes information for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) and all other bright (mpeak ≤ 17), spectroscopically confirmed supernovae discovered in 2016. We then gather the near-infrared through ultraviolet magnitudes of all host galaxies and the offsets of the supernovae from the centres of their hosts from public data bases. We illustrate the results using a sample that now totals 668 supernovae discovered since 2014 May 1, including the supernovae from our previous catalogues, with type distributions closely matching those of the ideal magnitude limited sample from Li et al. This is the third of a series of yearly papers on bright supernovae and their hosts from the ASAS-SN team