Generalised equilibrium of cosmological fluids in second-order thermodynamics

Combining the second-order entropy flow vector of the causal Israel-Stewart theory with the conformal Killing-vector property of $u_{i}/T$, where $u_{i}$ is the four-velocity of the medium and T its equilibrium temperature, we investigate generalized equilibrium states for cosmological fluids with nonconserved particle number. We calculate the corresponding equilibrium particle production rate and show that this quantity is reduced compared with the results of the previously studied first-order theory. Generalized equilibrium for massive particles turns out to be compatible with a dependence $\rho \propto a ^{-2}$ of the fluid energy density $\rho$ on the scale factor a of the Robertson-Walker metric and may be regarded as a realization of so-called K-matter.Comment: 17 pages, iopfts.tex file, submitted to Class. Quantum Gra

Stationary axisymmetric solutions involving a third order equation irreducible to Painlevé transcendents

International audienceWe extend the method of separation of variables, studied by Léauté and Marcilhacy [Ann. Inst. Henri Poincare, Sect. A 331, 363 (1979)], to obtain transcendent solutions of the field equations for stationary axisymmetric systems. These solutions depend on transcendent functions satisfying a third order differential equation. For some solutions this equation satisfies the necessary conditions, but not sufficient, to have fixed critical points

Letter: Parametrization of the Kerr-NUT Solution

International audienceThe dragging of the Kerr-NUT solution does not tend to zero at infinity. To modify this solution in order to produce a good asymptotic behaviour we transform it by introducing two further parameters with the aid of a SU(1,1) transformation followed by a unitary transformation. By imposing a certain relation between these parameters we obtain a new solution with a good asymptotic behaviour for any value of l, the NUT parameter. The new solution corresponds to a parametrized Kerr solution and we show that l is linked to the form of its ergosphere

Safety and efficacy of the Silk flow diverter: Insight from the DIVERSION prospective cohort study

BACKGROUND AND PURPOSE Flow diverters are considered as an essential tool in the stent-based treatment of complex intracranial aneurysms. We report here a subgroup analysis of the nationwide prospective DIVERSION study to investigate the safety and efficacy of the Silk flow diverter at 12 months follow-up. METHODS We performed a subgroup analysis of patients included in the DIVERSION, a national prospective cohort study including all flow diverters placement between 2012 and 2014 in France, and treated with the Silk. The primary outcome was the morbi-mortality at 12 months, including death, morbidity event and aneurysm retreatment within 12 months post-treatment. All reported serious events were adjudicated by an independent Data Safety and Monitoring Board. Satisfactory occlusion was defined as 3 or 4 on Kamran's scale by an independent imaging core laboratory during follow-up. RESULTS A total of 102 procedures involving 101 patients (mean age±standard deviation, 54.3±13.5 years) harbouring 118 aneurysms (113/118 located in the anterior circulation; mean size 8.2±7.1mm) were included. During the 12-month follow-up, 34 (33.3%) procedures experienced at least one morbi-mortality event: 3 deaths, 27 morbidity events and 4 retreatments. Overall, 1/3 deaths and 10/27 morbidity events were related to the device and/or the procedure, leading to a specific survival rate and a specific free-morbidity survival rate at 12 months of 98.98% [95% confidence interval, 92.98%-99.86%] and 89.73% [95%CI, 81.71%-94.36%], respectively. The rate of permanent-related neurological deficit was 5.9% within 12 months. One year follow-up imaging showed satisfactory occlusion in 82.2% of cases. CONCLUSION Flow diversion with the Silk device has a reasonable safety and effectiveness profile for the endovascular treatment of intracranial aneurysms

Mechanical Thrombectomy Outcomes With or Without Intravenous Thrombolysis

International audienceBackground and Purpose- Intravenous thrombolysis (IVT) within 4.5 hours of symptom onset is currently recommended before mechanical thrombectomy (MT). We compared functional outcome, neurological recovery, reperfusion, and adverse events according to the use or not of IVT before MT. Methods- This is a post hoc analysis of the ASTER trial (Contact Aspiration Versus Stent Retriever for Successful Revascularization). The primary outcome was favorable 90-day functional outcome defined as a modified Rankin Scale of ≤2. Secondary outcomes were successful reperfusion following all procedures and after the first-line procedure, number of device passes, and change in National Institutes of Health Stroke Scale score at 24 hours. Safety outcomes included 90-day mortality and any symptomatic intracerebral hemorrhage. Results- Three hundred eighty-one patients were included, 250 of whom received IVT before MT (IVT+MT group). There were no significant differences between IVT+MT and MT-alone groups in 90-day favorable functional outcome, in successful reperfusion rate (modified Thrombolysis In Cerebral Infarction 2b or 3), in National Institutes of Health Stroke Scale score improvement at 24 hours, or in hemorrhagic complication rate. The 90-day mortality rate in the IVT+MT group was lower than after MT alone (fully-adjusted risk ratio, 0.59; 95% CI, 0.39-0.88). In a subgroup of patients without anticoagulant medication before stroke onset, we observed in the IVT+MT group a better functional outcome (fully-adjusted risk ratio, 1.38; 95% CI, 1.02-1.89), a higher successful recanalization rate after first-line strategy (fully-adjusted risk ratio, 1.26; 95% CI, 1.05-1.50), and a lower mortality rate (fully-adjusted risk ratio, 0.58; 95% CI, 0.36-0.93). Conclusions- Our results show that IVT+MT patients in the ASTER trial have lower 90-day mortality compared with those receiving MT alone. In a selected population of patients without prestroke anticoagulation, we demonstrated that IVT associated with MT might improve functional outcome and recanalization while reducing mortality rates

Safety and efficacy of the Silk flow diverter: Insight from the DIVERSION prospective cohort study

International audienc

Rare Coding Variants in ANGPTL6 Are Associated with Familial Forms of Intracranial Aneurysm

International audienceIntracranial aneurysms (IAs) are acquired cerebrovascular abnormalities characterized by localized dilation and wall thinning in intracranial arteries, possibly leading to subarachnoid hemorrhage and severe outcome in case of rupture. Here, we identified one rare nonsense variant (c.1378A>T) in the last exon of ANGPTL6 (Angiopoietin-Like 6)—which encodes a circulating pro-angiogenic factor mainly secreted from the liver—shared by the four tested affected members of a large pedigree with multiple IA-affected case subjects. We showed a 50% reduction of ANGPTL6 serum concentration in individuals heterozygous for the c.1378A>T allele (p.Lys460Ter) compared to relatives homozygous for the normal allele, probably due to the non-secretion of the truncated protein produced by the c.1378A>T transcripts. Sequencing ANGPTL6 in a series of 94 additional index case subjects with familial IA identified three other rare coding variants in five case subjects. Overall, we detected a significant enrichment (p = 0.023) in rare coding variants within this gene among the 95 index case subjects with familial IA, compared to a reference population of 404 individuals with French ancestry. Among the 6 recruited families, 12 out of 13 (92%) individuals carrying IA also carry such variants in ANGPTL6, versus 15 out of 41 (37%) unaffected ones. We observed a higher rate of individuals with a history of high blood pressure among affected versus healthy individuals carrying ANGPTL6 variants, suggesting that ANGPTL6 could trigger cerebrovascular lesions when combined with other risk factors such as hypertension. Altogether, our results indicate that rare coding variants in ANGPTL6 are causally related to familial forms of IA

Endovascular therapy with or without intravenous thrombolysis in acute stroke with tandem occlusion

International audienceBackground Endovascular therapy (EVT) is effective and safe in patients with tandem occlusion. The benefit of intravenous thrombolysis (IVT) prior to EVT in acute tandem occlusion is debatable. Objective To compare EVT alone with EVT plus IVT in patients with acute ischemic stroke due to anterior circulation tandem occlusions. Methods This is an individual patient pooled analysis of the Thrombectomy In TANdem lesions (TITAN) and Endovascular Treatment in Ischemic Stroke (ETIS) Registries. Patients were divided into two groups based on prior IVT treatment: (1) IVT+ group, which included patients who received IVT prior to EVT, (2) IVT− group, which included patients who did not receive IVT prior to EVT. Propensity score (inverse probability of treatment weighting (IPTW)) was used to reduce baseline between-group differences. The primary outcome was favorable outcome—that is, modified Rankin Scale (mRS) score 0 to 2 at 90 days. Results Overall, 602 consecutive patients with an acute stroke with tandem occlusion were included (380 and 222 in the bridging therapy and EVT alone groups, respectively). Onset to imaging time was shorter in the IVT+ group (median 103 vs 140 min). In contrast, imaging to puncture time was longer in the IVT+ group (median 107 vs 91 min). In IPTW analysis, the IVT+ group had higher odds of favorable outcome, excellent outcome (90-day mRS score 0–1), and successful reperfusion (modified Thrombolysis in Cerebral Infarction score 2b/3 at the end of EVT). There was no difference in the risk of significant hemorrhagic complications between groups. In secondary analysis of patients treated with acute cervical internal carotid artery stenting, bridging therapy was associated with higher odds of favorable outcome and lower odds of mortality at 90 days. Conclusions Our results suggest that bridging therapy in patients with acute ischemic stroke due to anterior tandem occlusion is safe and may improve functional outcome, even in the setting of acute cervical internal carotid artery stenting during EVT