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The BRCT domain (BRCA1 C-terminus), first identified in the breast cancer suppressor protein BRCA1, is an evolutionarily conserved protein-protein interaction region of ∼95 amino acids found in a large number of proteins involved in DNA repair, recombination and cell cycle control. Here we describe the first threedimensional structure and fold of a BRCT domain determined by X-ray crystallography at 3.2 Å resolution. The structure has been obtained from the C-terminal region of the human DNA repair protein XRCC1, and comprises a four-stranded parallel β-sheet surrounded by three α-helices, which form an autonomously folded domain. The compact XRCC1 structure explains the observed sequence homology between different BRCT motifs and provides a framework for modelling other BRCT domains. Furthermore, the established structure of an XRCC1 BRCT homodimer suggests potential protein—protein interaction sites for the complementary BRCT domain in DNA ligase III, since these two domains form a stable heterodimeric complex. Based on the XRCC1 BRCT structure, we have constructed a model for the C-terminal BRCT domain of BRCA1, which frequently is mutated in familial breast and ovarian cancer. The model allows insights into the effects of such mutations on the fold of the BRCT domain. [ABSTRACT FROM AUTHOR]

Background: Uncertainty about optimal red blood cell transfusion thresholds in cardiac surgery is reflected in widely varying transfusion rates between surgeons and cardiac centres., Objective: To test the hypothesis that a restrictive compared with a liberal threshold for red blood cell transfusion after cardiac surgery reduces post-operative morbidity and health-care costs., Design: Multicentre, parallel randomised controlled trial and within-trial cost-utility analysis from a UK NHS and Personal Social Services perspective. We could not blind health-care staff but tried to blind participants. Random allocations were generated by computer and minimised by centre and operation., Setting: Seventeen specialist cardiac surgery centres in UK NHS hospitals., Participants: Patients aged > 16 years undergoing non-emergency cardiac surgery with post-operative haemoglobin < 9 g/dl. Exclusion criteria were: unwilling to have transfusion owing to beliefs; platelet, red blood cell or clotting disorder; ongoing or recurrent sepsis; and critical limb ischaemia., Interventions: Participants in the liberal group were eligible for transfusion immediately after randomisation (post-operative haemoglobin < 9 g/dl); participants in the restrictive group were eligible for transfusion if their post-operative haemoglobin fell to < 7.5 g/dl during the index hospital stay., Main Outcome Measures: The primary outcome was a composite outcome of any serious infectious (sepsis or wound infection) or ischaemic event (permanent stroke, myocardial infarction, gut infarction or acute kidney injury) during the 3 months after randomisation. Events were verified or adjudicated by blinded personnel. Secondary outcomes included blood products transfused; infectious events; ischaemic events; quality of life (European Quality of Life-5 Dimensions); duration of intensive care or high-dependency unit stay; duration of hospital stay; significant pulmonary morbidity; all-cause mortality; resource use, costs and cost-effectiveness., Results: We randomised 2007 participants between 15 July 2009 and 18 February 2013; four withdrew, leaving 1000 and 1003 in the restrictive and liberal groups, respectively. Transfusion rates after randomisation were 53.4% (534/1000) and 92.2% (925/1003). The primary outcome occurred in 35.1% (331/944) and 33.0% (317/962) of participants in the restrictive and liberal groups [odds ratio (OR) 1.11, 95% confidence interval (CI) 0.91 to 1.34; p = 0.30], respectively. There were no subgroup effects for the primary outcome, although some sensitivity analyses substantially altered the estimated OR. There were no differences for secondary clinical outcomes except for mortality, with more deaths in the restrictive group (4.2%, 42/1000 vs. 2.6%, 26/1003; hazard ratio 1.64, 95% CI 1.00 to 2.67; p = 0.045). Serious post-operative complications excluding primary outcome events occurred in 35.7% (354/991) and 34.2% (339/991) of participants in the restrictive and liberal groups, respectively. The total cost per participant from surgery to 3 months postoperatively differed little by group, just £182 less (standard error £488) in the restrictive group, largely owing to the difference in red blood cells cost. In the base-case cost-effectiveness results, the point estimate suggested that the restrictive threshold was cost-effective; however, this result was very uncertain partly owing to the negligible difference in quality-adjusted life-years gained., Conclusions: A restrictive transfusion threshold is not superior to a liberal threshold after cardiac surgery. This finding supports restrictive transfusion due to reduced consumption and costs of red blood cells. However, secondary findings create uncertainty about recommending restrictive transfusion and prompt a new hypothesis that liberal transfusion may be superior after cardiac surgery. Reanalyses of existing trial datasets, excluding all participants who did not breach the liberal threshold, followed by a meta-analysis of the reanalysed results are the most obvious research steps to address the new hypothesis about the possible harm of red blood cell transfusion., Trial Registration: Current Controlled Trials ISRCTN70923932., Funding: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 60. See the NIHR Journals Library website for further project information.

Background: Bevacizumab (Avastin®, Roche), which is used in cancer therapy, is the 'parent' molecule from which ranibizumab (Lucentis®, Novartis) was derived for the treatment of neovascular age-related macular degeneration (nAMD). There were reports in the literature on the effectiveness of bevacizumab in treating nAMD, but no trials. The cost per dose of bevacizumab is about 5-10% that of ranibizumab. This trial was a head-to-head comparison of these two drugs., Objective: To compare the clinical effectiveness and cost-effectiveness of ranibizumab and bevacizumab, and two treatment regimens, for nAMD., Design: Multicentre, factorial randomised controlled trial with within-trial cost-utility and cost-minimisation analyses from the perspective of the UK NHS. Participants, health professionals and researchers were masked to allocation of drug but not regimen. Computer-generated random allocations to combinations of ranibizumab or bevacizumab, and continuous or discontinuous regimen, were stratified by centre, blocked and concealed., Setting: Twenty-three ophthalmology departments in NHS hospitals., Participants: Patients ≥ 50 years old with active nAMD in the study eye with best corrected distance visual acuity (BCVA) ≥ 25 letters measured on a Early Treatment of Diabetic Retinopathy Study (ETDRS) chart. Previous treatment for nAMD, long-standing disease, lesion diameter > 6000 µm, thick blood at the fovea and any other confounding ocular disease were exclusion criteria. One eye per participant was studied; the fellow eye was treated according to usual care, if required., Interventions: Ranibizumab and bevacizumab were procured commercially. Doses were ranibizumab 0.5 mg or bevacizumab 1.25 mg. The repackaged bevacizumab was quality assured. All participants were treated at visits 0, 1 and 2. Participants randomised to the continuous regimen were treated monthly thereafter. Participants randomised to the discontinuous regimen were not retreated after visit 2 unless pre-specified criteria for active disease were met. If retreatment was needed, monthly injections over 3 months were mandated., Main Outcome Measures: The primary outcome was BCVA. The non-inferiority margin was 3.5 letters. Secondary outcomes were contrast sensitivity; near visual acuity; reading index; neovascular lesion morphology; generic and disease-specific patient-reported outcomes, including macular disease-specific quality of life; survival free from treatment failure; resource use; quality-adjusted life-years (QALYs); and development of new geographic atrophy (GA) (outcome added during the trial). Results are reported for the study eye, except for patient-reported outcomes., Results: Between 27 March 2008 and 15 October 2010, 610 participants were allocated and treated (314 ranibizumab, 296 bevacizumab; at 3 months, 305 continuous, 300 discontinuous). After 2 years, bevacizumab was neither non-inferior nor inferior to ranibizumab [-1.37 letters, 95% confidence interval (CI) -3.75 to +1.01 letters] and discontinuous treatment was neither non-inferior nor inferior to continuous treatment (-1.63 letters, 95% CI -4.01 to +0.75 letters). Lesion thickness at the fovea was similar by drug [geometric mean ratio (GMR) 0.96, 95% CI 0.90 to 1.03; p = 0.24] but 9% less with continuous treatment (GMR 0.91, 95% CI 0.85 to 0.97; p = 0.004). Odds of developing new GA during the trial were similar by drug [odds ratio (OR) 0.87, 95% CI 0.61 to 1.25; p = 0.46] but significantly higher with continuous treatment (OR 1.47, 95% CI 1.03 to 2.11; p = 0.033). Safety outcomes did not differ by drug but mortality was lower with continuous treatment (OR 0.47, 95% CI 0.22 to 1.03; p = 0.05). Continuous ranibizumab cost £3.5M per QALY compared with continuous bevacizumab; continuous bevacizumab cost £30,220 per QALY compared with discontinuous bevacizumab. These results were robust in sensitivity analyses., Conclusions: Ranibizumab and bevacizumab have similar efficacy. Discontinuing treatment and restarting when required results in slightly worse efficacy. Safety was worse with discontinuous treatment, although new GA developed more often with continuous treatment. Ranibizumab is not cost-effective, although it remains uncertain whether or not continuous bevacizumab is cost-effective compared with discontinuous bevacizumab at £20,000 per QALY threshold. Future studies should focus on the ocular safety of the two drugs, further optimisation of treatment regimens and criteria for stopping treatment., Trial Registration: Current Controlled Trials ISRCTN92166560., Funding: This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 19, No. 78. See the NIHR Journals Library website for further project information.