The type Ia supernova SNLS-03D3bb from a super-Chandrasekhar-mass white dwarf star

The acceleration of the expansion of the universe, and the need for Dark Energy, were inferred from the observations of Type Ia supernovae (SNe Ia). There is consensus that SNe Ia are thermonuclear explosions that destroy carbon-oxygen white dwarf stars that accrete matter from a companion star, although the nature of this companion remains uncertain. SNe Ia are thought to be reliable distance indicators because they have a standard amount of fuel and a uniform trigger -- they are predicted to explode when the mass of the white dwarf nears the Chandrasekhar mass -- 1.4 solar masses. Here we show that the high redshift supernova SNLS-03D3bb has an exceptionally high luminosity and low kinetic energy that both imply a super-Chandrasekhar mass progenitor. Super-Chandrasekhar mass SNe Ia should preferentially occur in a young stellar population, so this may provide an explanation for the observed trend that overluminous SNe Ia only occur in young environments. Since this supernova does not obey the relations that allow them to be calibrated as standard candles, and since no counterparts have been found at low redshift, future cosmology studies will have to consider contamination from such events.Comment: 9 pages, 4 figures. To appear in Nature Sept. 21. Accompanying News & Views in same issue. Supplementary information available at www.nature.com/natur

American College of Rheumatology Provisional Criteria for Clinically Relevant Improvement in Children and Adolescents With Childhood-Onset Systemic Lupus Erythematosus

10.1002/acr.23834ARTHRITIS CARE & RESEARCH715579-59

Effects of eight neuropsychiatric copy number variants on human brain structure

Many copy number variants (CNVs) confer risk for the same range of neurodevelopmental symptoms and psychiatric conditions including autism and schizophrenia. Yet, to date neuroimaging studies have typically been carried out one mutation at a time, showing that CNVs have large effects on brain anatomy. Here, we aimed to characterize and quantify the distinct brain morphometry effects and latent dimensions across 8 neuropsychiatric CNVs. We analyzed T1-weighted MRI data from clinically and non-clinically ascertained CNV carriers (deletion/duplication) at the 1q21.1 (n = 39/28), 16p11.2 (n = 87/78), 22q11.2 (n = 75/30), and 15q11.2 (n = 72/76) loci as well as 1296 non-carriers (controls). Case-control contrasts of all examined genomic loci demonstrated effects on brain anatomy, with deletions and duplications showing mirror effects at the global and regional levels. Although CNVs mainly showed distinct brain patterns, principal component analysis (PCA) loaded subsets of CNVs on two latent brain dimensions, which explained 32 and 29% of the variance of the 8 Cohen’s d maps. The cingulate gyrus, insula, supplementary motor cortex, and cerebellum were identified by PCA and multi-view pattern learning as top regions contributing to latent dimension shared across subsets of CNVs. The large proportion of distinct CNV effects on brain morphology may explain the small neuroimaging effect sizes reported in polygenic psychiatric conditions. Nevertheless, latent gene brain morphology dimensions will help subgroup the rapidly expanding landscape of neuropsychiatric variants and dissect the heterogeneity of idiopathic conditions

Immune-mediated inflammatory diseases and nutrition: results from an online survey on patients’ practices and perceptions

International audienceBackground: The central role of microbiota and the contribution of diet in immune-mediated inflammatory diseases (IMID) are increasingly examined. However, patients' perspectives on nutrition and its impact on their disease has not received a lot of attention. We aimed to directly collect information from patients with IMID about their dietary behaviors and their perceptions of the influence of nutrition on their disease. Methods: Adult patients with rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, Crohn's disease, ulcerative colitis or psoriasis registered in an online patient community were invited to participate in the study and complete an online self-administered questionnaire. We assessed patients' dietary knowledge and choices by collecting information on the diet regimens they were following or recommended and their perceptions of the diet and its consequences on their disease. Results: Fifty patients per target disease were included with a mean age of 48.1 years (95%CI 46.7-49.6). Other sociodemographic and clinical characteristics varied across the diseases. Since diagnosis, 44% of the patients changed their eating habits, mainly patients with inflammatory bowel disease with 69% of these making the change on their own initiative. Patients who did not change their diet habits reported not having received nutritional advice from their healthcare professionals (HCP) in 69% of the cases. The perceived impact of nutrition on their symptoms was mixed (overall 74% of the patients reported positive consequences and 60% negative ones) and varied across the diseases. Patients with psoriasis only experienced positive consequences from changing their diet, such as reduction of stress and improved mental health, while patients with Crohn's disease reported more negative effects such as increased fatigue and disturbed sleep. Patients with rheumatic diseases and ulcerative colitis reported weight loss and better physical fitness, but also increased fatigue. Conclusions: Even if differences exist across diseases, the importance of nutrition and its potential positive role in symptom management is acknowledged by the majority of the patients. However, there is a need and a demand from patients to receive more dietary advice. Developing therapeutic education tools on nutrition for people with IMID and involving patients' organizations would provide useful information and encourage communication between HCP and patients

Cu/Zn-SOD allows a discrimination of the two Dreissena species, the quagga and the zebra mussels

International audienc

Safety and efficacy of daridorexant in patients with insomnia disorder: results from two multicentre, randomised, double-blind, placebo-controlled, phase 3 trials.

BACKGROUND Daytime functioning is impaired in people with insomnia disorder. Currently available dual orexin receptor antagonists have shown efficacy in insomnia disorder, but do not address all aspects of this disease. We aimed to assess safety and efficacy of daridorexant, a novel orexin receptor antagonist, on night-time and daytime symptoms of insomnia. METHODS We did two multicentre, randomised, double-blind, placebo-controlled, phase 3 trials at 156 sites in 17 countries. Adults (aged ≥18 years) with insomnia disorder were randomly assigned using interactive response technology (1:1:1) to receive daridorexant 50 mg, 25 mg, or placebo (study 1) or daridorexant 25 mg, 10 mg, or placebo (study 2) every evening for 3 months. Participants, investigators, and site personnel were masked to treatment allocation. The primary endpoints were change from baseline in wake time after sleep onset (WASO) and latency to persistent sleep (LPS), measured by polysomnography, at months 1 and 3. The secondary endpoints were change from baseline in self-reported total sleep time and the sleepiness domain score of the Insomnia Daytime Symptoms and Impacts Questionnaire (IDSIQ) at months 1 and 3. Study-wise type I error rate (5%) was controlled for all pairwise comparisons. Efficacy was analysed in all randomly assigned participants, and safety in all participants who received at least one dose of treatment. The studies are registered at ClinicalTrials.gov, NCT03545191 (study 1) and NCT03575104 (study 2). FINDINGS Between June 4, 2018 and Feb 25, 2020, 930 participants were randomly assigned to receive daridorexant 50 mg (n=310), daridorexant 25 mg (n=310), or placebo (n=310) in study 1. Between May 29, 2018, and May 14, 2020, 924 participants were randomly assigned to receive daridorexant 25 mg (n=309), daridorexant 10 mg (n=307), or placebo (n=308) in study 2. In study 1, WASO and LPS were significantly reduced among participants in the daridorexant 50 mg group compared with participants in the placebo group at month 1 (least squares mean [LSM] difference -22·8 min [95% CI -28·0 to -17·6], p<0·0001 for WASO; -11·4 min [-16·0 to -6·7], p<0·0001 for LPS) and month 3 (-18·3 min [-23·9 to -12·7], p<0·0001 for WASO; -11·7 min [-16·3 to -7·0], p<0·0001 for LPS). WASO and LPS were significantly reduced among participants in the daridorexant 25 mg group compared with the placebo group at month 1 (LSM difference -12·2 min [-17·4 to -7·0], p<0·0001 for WASO; -8·3 min [-13·0 to -3·6], p=0·0005 for LPS) and month 3 (-11·9 min [-17·5 to -6·2], p<0·0001 for WASO; -7·6 min [-12·3 to -2·9], p=0·0015 for LPS). Compared with placebo, participants in the daridorexant 50 mg group had significantly improved self-reported total sleep time at month 1 (LSM difference 22·1 min [14·4 to 29·7], p<0·0001) and month 3 (19·8 min [10·6 to 28·9], p<0·0001), and IDSIQ sleepiness domain scores at month 1 (-1·8 [-2·5 to -1·0], p<0·0001) and month 3 (-1·9 [-2·9 to -0·9], p=0·0002). Compared with the placebo group, participants in the daridorexant 25 mg group had significantly improved self-reported total sleep time at month 1 (LSM difference 12·6 min [5·0 to 20·3], p=0·0013) and month 3 (9·9 min [0·8 to 19·1], p=0·033), but not IDSIQ sleepiness domain scores (-0·8 [-1·5 to 0·01], p=0·055 at month 1; -1·0 [-2·0 to 0·01], p=0·053 at month 3). In study 2, WASO was significantly reduced among participants in the daridorexant 25 mg group compared with participants in the placebo group at month 1 (LSM difference -11·6 min [-17·6 to -5·6], p=0·0001) and month 3 (-10·3 min [-17·0 to -3·5], p=0·0028), whereas no significant differences in LPS were observed at month 1 (-6·5 min [-12·3 to -0·6], p=0·030) or month 3 (-9·0 [-15·3 to -2·7], p=0·0053). Compared with the placebo group, participants in the daridorexant 25 mg group had significant improvement in self-reported total sleep time at month 1 (LSM difference 16·1 min [8·2 to 24·0], p<0·0001) and month 3 (19·1 [10·1 to 28·0], p<0·0001), but not in IDSIQ sleepiness domain scores (-0·8 [-1·6 to 0·1], p=0·073 at month 1; -1·3 [-2·2 to -0·3], p=0·012 at month 3). Compared with the placebo group, no significant differences were observed among participants in the daridorexant 10 mg group for WASO (LSM difference -2·7 min [-8·7 to 3·2], p=0·37 at month 1; -2·0 [-8·7 to 4·8], p=0·57 at month 3), LPS (-2·6 min [-8·4 to 3·2], p=0·38 at month 1; -3·2 min [-9·5 to 3·1], p=0·32 at month 3), self-reported total sleep time (13·4 min [5·5 to 21·2], p=0·0009 at month 1; 13·6 min [4·7 to 22·5], p=0·0028 at month 3), nor IDSIQ sleepiness domain scores (-0·4 [-1·3 to 0·4], p=0·30 at month 1; -0·7 [-1·7 to 0·2], p=0·14 at month 3). Overall incidence of adverse events was comparable between treatment groups (116 [38%] of 308 participants in the daridorexant 50 mg group, 117 [38%] of 310 in the daridorexant 25 mg group, and 105 [34%] of 309 in the placebo group in study 1; 121 [39%] of 308 participants in the daridorexant 25 mg group, 117 [38%] of 306 in the daridorexant 10 mg group, and 100 [33%] of 306 in the placebo group). Nasopharyngitis and headache were the most common adverse events in all groups. One death (cardiac arrest) occurred in the daridorexant 25 mg group in study 1, which was not deemed to be treatment-related. INTERPRETATION Daridorexant 25 mg and 50 mg improved sleep outcomes, and daridorexant 50 mg also improved daytime functioning, in people with insomnia disorder, with a favourable safety profile. FUNDING Idorsia Pharmaceuticals

Molecular response of mussels Dreissena spp. to contrasted environments: comparison of different French and Canadian populations

International audienc