XTE J1752-223 in outburst: a persistent radio jet, dramatic flaring, multiple ejections and linear polarisation

The black hole candidate, XTE J1752-223, was discovered in 2009 October when it entered an outburst. We obtained radio data from the Australia Telescope Compact Array for the duration of the ~9 month event. The lightcurves show that the radio emission from the compact jet persisted for the duration of an extended hard state and through the transition to the intermediate state. The flux then rose rapidly by a factor of 10 and the radio source entered a series of at least 7 maxima, the first of which was likely to be emission associated with the compact jet. The subsequent 6 flares were accompanied by variable behaviour in terms of radio spectrum, degree of linear polarisation, morphology and associated X-ray behaviour. They were, however, remarkably similar in terms of the estimated minimum power required to launch such an ejection event. We compare the timing of radio peaks with the location of the ejecta, imaged by contemporaneous VLBI experiments. We then discuss the mechanism behind the events, in terms of whether discrete ejections is the most likely description of the behaviour. One ejection, at least, appears to be travelling with apparent superluminal motion. The range of properties, however, suggests that mutiple mechanisms may be relevant and that at least some of the emission is coming from shocked interactions amongst the ejecta and between the ejecta and the interstellar medium. We also compare the radio flux density with the X-ray source during the hard state and conclude that XTE J1752-223 is a radio-weak/X-ray-bright outlier on the universal correlation for black hole transient sources.Comment: 14 pages; Accepted for publication in MNRA

Mangafodipir Protects against Hepatic Ischemia-Reperfusion Injury in Mice

Mangafodipir is a contrast agent used in magnetic resonance imaging that concentrates in the liver and displays pleiotropic antioxidant properties. Since reactive oxygen species are involved in ischemia-reperfusion damages, we hypothesized that the use of mangafodipir could prevent liver lesions in a mouse model of hepatic ischemia reperfusion injury. Mangafodipir (MnDPDP) was compared to ischemic preconditioning and intermittent inflow occlusion for the prevention of hepatic ischemia-reperfusion injury in the mouse.Mice were subjected to 70% hepatic ischemia (continuous ischemia) for 90 min. Thirty minutes before the ischemic period, either mangafodipir (10 mg/kg) or saline was injected intraperitoneally. Those experimental groups were compared with one group of mice preconditioned by 10 minutes' ischemia followed by 15 minutes' reperfusion, and one group with intermittent inflow occlusion. Hepatic ischemia-reperfusion injury was evaluated by measurement of serum levels of aspartate aminotransferase (ASAT) activity, histologic analysis of the livers, and determination of hepatocyte apoptosis (cytochrome c release, caspase 3 activity). The effect of mangafodipir on the survival rate of mice was studied in a model of total hepatic ischemia.<0.01), and by higher rates of survival in treated than in untreated animals (P<0.001). The level of protection by mangafodipir was similar to that observed following intermittent inflow occlusion and higher than after ischemic preconditioning.Mangafodipir is a potential new preventive treatment for hepatic ischemia-reperfusion injury

The Athena X-ray Integral Field Unit: a consolidated design for the system requirement review of the preliminary definition phase

Instrumentatio

BRAF mutation is not associated with an increased risk of recurrence in patients undergoing resection of colorectal liver metastases

International audienceBackground: BRAF mutation is associated with a poor prognosis in patients with metastatic colorectal cancer. For patients with resectable colorectal liver metastases (CRLMs), the prognostic impact of BRAF mutation is unknown and the benefit of surgery debated. This nationwide intergroup (ACHBT, FRENCH, AGEO) study aimed to evaluate the oncological outcome of patients undergoing liver resection for BRAF-mutated CRLMs.Methods: The study included patients who underwent resection for BRAF-mutated CRLMs in 24 centres between 2012 and 2016. A case-matched comparison was made with 183 patients who underwent resection of CRLMs with wild-type BRAF during the same interval.Results: Sixty-six patients who underwent resection for BRAF-mutated CRLMs in 24 centres were compared with 183 patients with wild-type BRAF. The 1- and 3-year disease-free survival (DFS) rates were 46 and 19 per cent for the BRAF-mutated group, and 55·4 and 27·8 per cent for the group with wild-type BRAF (P = 0·430). In multivariable analysis, BRAF mutation was not associated with worse DFS (hazard ratio 1·16, 95 per cent c.i. 0·72 to 1·85; P = 0·547). The 1- and 3-year overall survival rates after surgery were 94 and 54 per cent respectively among patients with BRAF mutation, and 95·8 and 82·9 per cent in those with wild-type BRAF (P = 0·004). Median survival after disease progression was 23·0 (95 per cent c.i. 11·0 to 35·0) months among patients with mutated BRAF and 44·3 (35·9 to 52·6) months in those with wild-type BRAF (P = 0·050). Multisite disease progression was more common in the BRAF-mutated group (48 versus 29·8 per cent; P = 0·034).Conclusion: These results support surgical treatment for resectable BRAF-mutated CRLM, as BRAF mutation by itself does not increase the risk of relapse after resection. BRAF mutation is associated with worse survival in patients whose disease relapses after resection of CRLM, as for non-metastatic colorectal cancer