12 research outputs found

    Baryon fractions in clusters of galaxies: evidence against a preheating model for entropy generation

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    The Millennium Gas project aims to undertake smoothed-particle hydrodynamic resimulations of the Millennium Simulation, providing many hundred massive galaxy clusters for comparison with X-ray surveys (170 clusters with kTsl > 3 keV). This paper looks at the hot gas and stellar fractions of clusters in simulations with different physical heating mechanisms. These fail to reproduce cool-core systems but are successful in matching the hot gas profiles of non-cool-core clusters. Although there is immense scatter in the observational data, the simulated clusters broadly match the integrated gas fractions within r500 . In line with previous work, however, they fare much less well when compared to the stellar fractions, having a dependence on cluster mass that is much weaker than is observed. The evolution with redshift of the hot gas fraction is much larger in the simulation with early preheating than in one with continual feedback; observations favour the latter model. The strong dependence of hot gas fraction on cluster physics limits its use as a probe of cosmological parameters.Comment: 16 pages, 18 figures, 4 tables. Accepted for publication in MNRA

    Sunyaev-Zel'dovich clusters in millennium gas simulations

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    Large surveys using the Sunyaev–Zel’dovich (SZ) effect to find clusters of galaxies are now starting to yield large numbers of systems out to high redshift, many of which are new dis- coveries. In order to provide theoretical interpretation for the release of the full SZ cluster samples over the next few years, we have exploited the large-volume Millennium gas cosmo- logical N-body hydrodynamics simulations to study the SZ cluster population at low and high redshift, for three models with varying gas physics. We confirm previous results using smaller samplesthattheintrinsic(spherical)Y500–M500relationhasverylittlescatter(σlog10Y ≃0.04), is insensitive to cluster gas physics and evolves to redshift 1 in accordance with self-similar expectations. Our preheating and feedback models predict scaling relations that are in excel- lent agreement with the recent analysis from combined Planck and XMM–Newton data by the Planck Collaboration. This agreement is largely preserved when r500 and M500 are derived using thehydrostaticmassproxy,YX,500,albeitwithsignificantlyreducedscatter(σlog10Y ≃0.02),a result that is due to the tight correlation between Y500 and YX,500. Interestingly, this assumption also hides any bias in the relation due to dynamical activity. We also assess the importance of projection effects from large-scale structure along the line of sight, by extracting cluster Y500 values from 50 simulated 5 × 5-deg2 sky maps. Once the (model-dependent) mean signal is subtracted from the maps we find that the integrated SZ signal is unbiased with respect to the underlying clusters, although the scatter in the (cylindrical) Y500–M500 relation increases in the preheating case, where a significant amount of energy was injected into the intergalactic medium at high redshift. Finally, we study the hot gas pressure profiles to investigate the origin of the SZ signal and find that the largest contribution comes from radii close to r500 in all cases. The profiles themselves are well described by generalized Navarro, Frenk & White profiles but there is significant cluster-to-cluster scatter. In conclusion, our results support the notion that Y500 is a robust mass proxy for use in cosmological analyses with clusters

    Ten-year mortality, disease progression, and treatment-related side effects in men with localised prostate cancer from the ProtecT Randomised Controlled Trial according to treatment received

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    BACKGROUND:The ProtecT trial reported intention-to-treat analysis of men with localised prostate cancer (PCa) randomly allocated to active monitoring (AM), radical prostatectomy, and external beam radiotherapy. OBJECTIVE:To determine report outcomes according to treatment received in men in randomised and treatment choice cohorts. DESIGN, SETTING, AND PARTICIPANTS:This study focuses on secondary care. Men with clinically localised prostate cancer at one of nine UK centres were invited to participate in the treatment trial comparing AM, radical prostatectomy, and radiotherapy. INTERVENTION:Two cohorts included 1643 men who agreed to be randomised; 997 declined randomisation and chose treatment. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS:Health-related quality of life impacts on urinary, bowel, and sexual function were assessed using patient-reported outcome measures. Analysis was carried out based on treatment received for each cohort and on pooled estimates using meta-analysis. Differences were estimated with adjustment for known prognostic factors using propensity scores. RESULTS AND LIMITATIONS:According to treatment received, more men receiving AM died of PCa (AM 1.85%, surgery 0.67%, radiotherapy 0.73%), whilst this difference remained consistent with chance in the randomised cohort (p=0.08); stronger evidence was found in the exploratory analyses (randomised plus choice cohort) when AM was compared with the combined radical treatment group (p=0.003). There was also strong evidence that metastasis (AM 5.6%, surgery 2.4%, radiotherapy 2.7%) and disease progression (AM 20.35%, surgery 5.87%, radiotherapy 6.62%) were more common in the AM group. Compared with AM, there were higher risks of sexual dysfunction (95% at 6mo) and urinary incontinence (55% at 6mo) after surgery, and of sexual dysfunction (88% at 6mo) and bowel dysfunction (5% at 6mo) after radiotherapy. The key limitations are the potential for bias when comparing groups defined by treatment received and outdating of the interventions being evaluated during the lengthy follow-up required in trials of screen-detected PCa. CONCLUSIONS:Analyses according to treatment received showed increased rates of disease-related events and lower rates of patient-reported harms in men managed by AM compared with men managed by radical treatment, and stronger evidence of greater PCa mortality in the AM group. PATIENT SUMMARY:More than 90 out of every 100 men with localised prostate cancer do not die of prostate cancer within 10yr, irrespective of whether treatment is by means of monitoring, surgery, or radiotherapy. Side effects on sexual and bladder function are much better after active monitoring, but the risks of spreading of prostate cancer are more common

    Functional and quality of life outcomes of localised prostate cancer treatments (prostate testing for cancer and treatment [ProtecT] study)

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    Objective To investigate the functional and quality of life (QoL) outcomes of treatments for localised prostate cancer and inform treatment decision-making. Patients and Methods Men aged 50–69 years diagnosed with localised prostate cancer by prostate-specific antigen testing and biopsies at nine UK centres in the Prostate Testing for Cancer and Treatment (ProtecT) trial were randomised to, or chose one of, three treatments. Of 2565 participants, 1135 men received active monitoring (AM), 750 a radical prostatectomy (RP), 603 external-beam radiotherapy (EBRT) with concurrent androgen-deprivation therapy (ADT) and 77 low-dose-rate brachytherapy (BT, not a randomised treatment). Patient-reported outcome measures (PROMs) completed annually for 6 years were analysed by initial treatment and censored for subsequent treatments. Mixed effects models were adjusted for baseline characteristics using propensity scores. Results Treatment-received analyses revealed different impacts of treatments over 6 years. Men remaining on AM experienced gradual declines in sexual and urinary function with age (e.g., increases in erectile dysfunction from 35% of men at baseline to 53% at 6 years and nocturia similarly from 20% to 38%). Radical treatment impacts were immediate and continued over 6 years. After RP, 95% of men reported erectile dysfunction persisting for 85% at 6 years, and after EBRT this was reported by 69% and 74%, respectively (P < 0.001 compared with AM). After RP, 36% of men reported urinary leakage requiring at least 1 pad/day, persisting for 20% at 6 years, compared with no change in men receiving EBRT or AM (P < 0.001). Worse bowel function and bother (e.g., bloody stools 6% at 6 years and faecal incontinence 10%) was experienced by men after EBRT than after RP or AM (P < 0.001) with lesser effects after BT. No treatment affected mental or physical QoL. Conclusion Treatment decision-making for localised prostate cancer can be informed by these 6-year functional and QoL outcomes

    CCN3 is dynamically regulated by treatment and disease state in multiple sclerosis

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    Background: Multiple sclerosis (MS) is an immune-mediated disease that damages myelin in the central nervous system (CNS). We investigated the profile of CCN3, a known regulator of immune function and a potential mediator of myelin regeneration, in multiple sclerosis in the context of disease state and disease-modifying treatment. Methods: CCN3 expression was analysed in plasma, immune cells, CSF and brain tissue of MS patient groups and control subjects by ELISA, western blot, qPCR, histology and in situ hybridization. Results: Plasma CCN3 levels were comparable between collective MS cohorts and controls but were significantly higher in progressive versus relapsing-remitting MS and between patients on interferon-β versus natalizumab. Higher body mass index was associated with higher CCN3 levels in controls as reported previously, but this correlation was absent in MS patients. A significant positive correlation was found between CCN3 levels in matched plasma and CSF of MS patients which was absent in a comparator group of idiopathic intracranial hypertension patients. PBMCs and CD4+ T cells significantly upregulated CCN3 mRNA in MS patients versus controls. In the CNS, CCN3 was detected in neurons, astrocytes and blood vessels. Although overall levels of area immunoreactivity were comparable between non-affected, demyelinated and remyelinated tissue, the profile of expression varied dramatically. Conclusions: This investigation provides the first comprehensive profile of CCN3 expression in MS and provides rationale to determine if CCN3 contributes to neuroimmunological functions in the CNS

    HDAC1 nuclear export induced by pathological conditions is essential for the onset of axonal damage

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    Histone deacetylase 1 (HDAC1) is a nuclear enzyme involved in transcriptional repression. We detected cytosolic HDAC1 in damaged axons in brains of humans with multiple sclerosis and of mice with cuprizone-induced demyelination, in ex vivo models of demyelination and in cultured neurons exposed to glutamate and tumor necrosis factor-α. Nuclear export of HDAC1 was mediated by the interaction with the nuclear receptor CRM-1 and led to impaired mitochondrial transport. The formation of complexes between exported HDAC1 and members of the kinesin family of motor proteins hindered the interaction with cargo molecules, thereby inhibiting mitochondrial movement and inducing localized beading. This effect was prevented by inhibiting HDAC1 nuclear export with leptomycin B, treating neurons with pharmacological inhibitors of HDAC activity or silencing HDAC1 but not other HDAC isoforms. Together these data identify nuclear export of HDAC1 as a critical event for impaired mitochondrial transport in damaged neurons

    The XMM Cluster Survey: optical analysis methodology and the first data release

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    The XMM Cluster Survey (XCS) is a serendipitous search for galaxy clusters using all publicly available data in the XMM–Newton Science Archive. Its main aims are to measure cosmological parameters and trace the evolution of X-ray scaling relations. In this paper we present the first data release from the XMM Cluster Survey (XCS-DR1). This consists of 503 optically confirmed, serendipitously detected, X-ray clusters. Of these clusters, 256 are new to the literature and 357 are new X-ray discoveries. We present 463 clusters with a redshift estimate (0.06 1.0, including a new spectroscopically confirmed cluster at z= 1.01); (ii) 66 clusters with high TX (>5 keV); (iii) 130 clusters/groups with low TX (<2 keV); (iv) 27 clusters with measured TX values in the Sloan Digital Sky Survey (SDSS) ‘Stripe 82’ co-add region; (v) 77 clusters with measured TX values in the Dark Energy Survey region; (vi) 40 clusters detected with sufficient counts to permit mass measurements (under the assumption of hydrostatic equilibrium); (vii) 104 clusters that can be used for applications such as the derivation of cosmological parameters and the measurement of cluster scaling relations. The X-ray analysis methodology used to construct and analyse the XCS-DR1 cluster sample has been presented in a companion paper, Lloyd-Davies et al

    Genome-wide association study identifies multiple susceptibility loci for pulmonary fibrosis.

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    To access publisher's full text version of this article. Please click on the hyperlink in Additional Links field.We performed a genome-wide association study of non-Hispanic, white individuals with fibrotic idiopathic interstitial pneumonias (IIPs; n = 1,616) and controls (n = 4,683), with follow-up replication analyses in 876 cases and 1,890 controls. We confirmed association with TERT at 5p15, MUC5B at 11p15 and the 3q26 region near TERC, and we identified seven newly associated loci (Pmeta = 2.4 × 10(-8) to 1.1 × 10(-19)), including FAM13A (4q22), DSP (6p24), OBFC1 (10q24), ATP11A (13q34), DPP9 (19p13) and chromosomal regions 7q22 and 15q14-15. Our results suggest that genes involved in host defense, cell-cell adhesion and DNA repair contribute to risk of fibrotic IIPs.National Heart, Lung, and Blood Institute /R01-HL095393 R01-HL097163 P01-HL092870 RC2-HL101715 U01-HL089897 U01-HL089856 U01-HL108642 P50-HL0894932Veterans Administration/1I01BX001534Dorothy P. and Richard P. Simmons Center and InterMun

    Genome-wide association study identifies multiple susceptibility loci for pulmonary fibrosis

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