Broad-band X-ray spectral analysis of the Seyfert 1 galaxy GRS 1734-292

We discuss the broad-band X-ray spectrum of GRS 1734−292 obtained from non-simultaneous XMM–Newton and NuSTAR (Nuclear Spectroscopic Telescope Array) observations, performed in 2009 and 2014, respectively. GRS1734−292 is a Seyfert 1 galaxy, located near the Galactic plane at z = 0.0214. The NuSTAR spectrum (3–80 keV) is dominated by a primary power-law continuum with Γ = 1.65 ± 0.05 and a high-energy cut-off Ec=53+11−8 keV, one of the lowest measured by NuSTAR in a Seyfert galaxy. Comptonization models show a temperature of the coronal plasma of kTe=11.9+1.2−0.9 keV and an optical depth, assuming a slab geometry, τ=2.98+0.16−0.19 or a similar temperature and τ=6.7+0.3−0.4 assuming a spherical geometry. The 2009 XMM–Newton spectrum is well described by a flatter intrinsic continuum (⁠Γ=1.47+0.07−0.03⁠) and one absorption line due to Fe XXV Kα produced by a warm absorber. Both data sets show a modest iron Kα emission line at 6.4 keV and the associated Compton reflection, due to reprocessing from neutral circumnuclear material

A Spontaneous Mutation in Contactin 1 in the Mouse

Mutations in the gene encoding the immunoglobulin-superfamily member cell adhesion molecule contactin1 (CNTN1) cause lethal congenital myopathy in human patients and neurodevelopmental phenotypes in knockout mice. Whether the mutant mice provide an accurate model of the human disease is unclear; resolving this will require additional functional tests of the neuromuscular system and examination of Cntn1 mutations on different genetic backgrounds that may influence the phenotype. Toward these ends, we have analyzed a new, spontaneous mutation in the mouse Cntn1 gene that arose in a BALB/c genetic background. The overt phenotype is very similar to the knockout of Cntn1, with affected animals having reduced body weight, a failure to thrive, locomotor abnormalities, and a lifespan of 2–3 weeks. Mice homozygous for the new allele have CNTN1 protein undetectable by western blotting, suggesting that it is a null or very severe hypomorph. In an analysis of neuromuscular function, neuromuscular junctions had normal morphology, consistent with previous studies in knockout mice, and the muscles were able to generate appropriate force when normalized for their reduced size in late stage animals. Therefore, the Cntn1 mutant mice do not show evidence for a myopathy, but instead the phenotype is likely to be caused by dysfunction in the nervous system. Given the similarity of CNTN1 to other Ig-superfamily proteins such as DSCAMs, we also characterized the expression and localization of Cntn1 in the retinas of mutant mice for developmental defects. Despite widespread expression, no anomalies in retinal anatomy were detected histologically or using a battery of cell-type specific antibodies. We therefore conclude that the phenotype of the Cntn1 mice arises from dysfunction in the brain, spinal cord or peripheral nervous system, and is similar in either a BALB/c or B6;129;Black Swiss background, raising a possible discordance between the mouse and human phenotypes resulting from Cntn1 mutations

The design of a randomized, placebo-controlled, dose-ranging trial to investigate the efficacy and safety of the ADAMTS-5 inhibitor S201086/GLPG1972 in knee osteoarthritis

Objective This study aims to assess the efficacy of the anticatabolic ‘a disintegrin and metalloproteinase with thrombospondin motif-5’ (ADAMTS-5) inhibitor, S201086/GLPG1972, in slowing cartilage loss in participants with knee osteoarthritis (OA). Design ROCCELLA (NCT03595618) is a randomized, double-blind, placebo-controlled, parallel-group, dose-ranging, phase 2 trial. We plan to enrol a total of 852 participants with knee OA across 12 countries. Participants will be randomized 1:1:1:1 to receive 75, 150 or 300 ​mg S201086/GLPG1972, or placebo orally, once daily for 52 weeks. Eligible participants will be aged 40–75 years and have predominantly medial knee OA with centrally read Kellgren–Lawrence grade 2 or 3, OARSI atlas medial femorotibial joint space narrowing grade 1 or 2, and consistent moderate to severe baseline pain. The primary endpoint will be the change from baseline to week 52 in magnetic resonance imaging-assessed central medial femorotibial compartment cartilage thickness. Secondary endpoints will include other structural outcomes, and patient-reported outcomes, as well as safety and pharmacokinetic assessments. Study sites will be assessed for eligibility based on factors including imaging quality, and images will be centrally read and quality checked. Conclusions Using strict inclusion criteria and leading imaging techniques with stringent quality controls, the ROCCELLA trial will evaluate the efficacy of S201086/GLPG1972 in slowing cartilage loss in participants with knee OA. The selected eligibility criteria should enrich for participants with OA who experience sufficient cartilage loss to allow detection of a substantial treatment effect

N-Myc and GCN5 Regulate Significantly Overlapping Transcriptional Programs in Neural Stem Cells

Here we examine the functions of the Myc cofactor and histone acetyltransferase, GCN5/KAT2A, in neural stem and precursor cells (NSC) using a conditional knockout approach driven by nestin-cre. Mice with GCN5-deficient NSC exhibit a 25% reduction in brain mass with a microcephaly phenotype similar to that observed in nestin-cre driven knockouts of c- or N-myc. In addition, the loss of GCN5 inhibits precursor cell proliferation and reduces their populations in vivo, as does loss of N-myc. Gene expression analysis indicates that about one-sixth of genes whose expression is affected by loss of GCN5 are also affected in the same manner by loss of N-myc. These findings strongly support the notion that GCN5 protein is a key N-Myc transcriptional cofactor in NSC, but are also consistent with recruitment of GCN5 by other transcription factors and the use by N-Myc of other histone acetyltransferases. Putative N-Myc/GCN5 coregulated transcriptional pathways include cell metabolism, cell cycle, chromatin, and neuron projection morphogenesis genes. GCN5 is also required for maintenance of histone acetylation both at its putative specific target genes and at Myc targets. Thus, we have defined an important role for GCN5 in NSC and provided evidence that GCN5 is an important Myc transcriptional cofactor in vivo

Neocortical Axon Arbors Trade-off Material and Conduction Delay Conservation

The brain contains a complex network of axons rapidly communicating information between billions of synaptically connected neurons. The morphology of individual axons, therefore, defines the course of information flow within the brain. More than a century ago, Ramón y Cajal proposed that conservation laws to save material (wire) length and limit conduction delay regulate the design of individual axon arbors in cerebral cortex. Yet the spatial and temporal communication costs of single neocortical axons remain undefined. Here, using reconstructions of in vivo labelled excitatory spiny cell and inhibitory basket cell intracortical axons combined with a variety of graph optimization algorithms, we empirically investigated Cajal's conservation laws in cerebral cortex for whole three-dimensional (3D) axon arbors, to our knowledge the first study of its kind. We found intracortical axons were significantly longer than optimal. The temporal cost of cortical axons was also suboptimal though far superior to wire-minimized arbors. We discovered that cortical axon branching appears to promote a low temporal dispersion of axonal latencies and a tight relationship between cortical distance and axonal latency. In addition, inhibitory basket cell axonal latencies may occur within a much narrower temporal window than excitatory spiny cell axons, which may help boost signal detection. Thus, to optimize neuronal network communication we find that a modest excess of axonal wire is traded-off to enhance arbor temporal economy and precision. Our results offer insight into the principles of brain organization and communication in and development of grey matter, where temporal precision is a crucial prerequisite for coincidence detection, synchronization and rapid network oscillations

Implementation of the OMERACT Psoriatic Arthritis Magnetic Resonance Imaging Scoring System in a randomized phase IIb study of abatacept in psoriatic arthritis

Objectives Investigate if the OMERACT Psoriatic Arthritis MRI Scoring System (PsAMRIS), including a novel total inflammation score, shows sensitivity to change with an agent (abatacept) known to impact clinical outcomes in PsA. Methods Post hoc analysis of randomized phase IIb study of abatacept in patients with PsA and inadequate DMARD response. Participants received one of three abatacept dosing regimens (ABA3, ABA10 or ABA30/10 mg/kg [30 mg/kg switched to 10 mg/kg after two doses]) or placebo until day (D)169, then ABA10 through D365. MRIs at baseline, D85, D169 and D365 were centrally evaluated by two readers blinded to chronological order and treatment arm. Synovitis, osteitis, tenosynovitis, periarticular inflammation, bone erosions, joint space narrowing and bone proliferation were assessed using PsAMRIS. A novel total inflammation score was tested. Results MRIs for 123 patients were included. D169: ABA10 and ABA30/10 significantly reduced MRI synovitis and tenosynovitis, respectively, vs placebo (differences −0.966 [p = 0.039] and −1.652 [p = 0.014], respectively). Synovitis in the placebo group increased non-significantly from baseline to D169; total inflammation and tenosynovitis decreased non-significantly; all measures improved significantly after switch to ABA10 (−1.019, −0.940, −2.275 [p < 0.05], respectively, D365 vs D169). Structural outcomes changed minimally across groups. Conclusion Adults with PsA receiving ABA10 and ABA30/10 demonstrated significant resolution of inflammatory components of disease, confirmed by MRI, with synovitis and tenosynovitis improvements consistent with previously reported clinical responses for these doses. Results indicate that reduction in OMERACT PsAMRIS inflammation scores may provide proof of tissue-level efficacy in PsA clinical trials. ClinicalTrials.gov registration ClinicalTrials.gov, https://clinicaltrials.gov, NCT0053431

Nicotinamide provides neuroprotection in glaucoma by protecting against mitochondrial and metabolic dysfunction

Nicotinamide adenine dinucleotide (NAD) is a REDOX cofactor and metabolite essential for neuronal survival. Glaucoma is a common neurodegenerative disease in which neuronal levels of NAD decline. We assess the effects of nicotinamide (a precursor to NAD) on retinal ganglion cells (the affected neuron in glaucoma) in normal physiological conditions and across a range of glaucoma relevant insults including mitochondrial stress and axon degenerative insults. We demonstrate retinal ganglion cell somal, axonal, and dendritic neuroprotection by nicotinamide in rodent models which represent isolated ocular hypertensive, axon degenerative, and mitochondrial degenerative insults. We performed metabolomics enriched for small molecular weight metabolites for the retina, optic nerve, and superior colliculus which demonstrates that ocular hypertension induces widespread metabolic disruption, including consistent changes to α-ketoglutaric acid, creatine/creatinine, homocysteine, and glycerophosphocholine. This metabolic disruption is prevented by nicotinamide. Nicotinamide provides further neuroprotective effects by increasing oxidative phosphorylation, buffering and preventing metabolic stress, and increasing mitochondrial size and motility whilst simultaneously dampening action potential firing frequency. These data support continued determination of the utility of long-term nicotinamide treatment as a neuroprotective therapy for human glaucoma