Search

The realisation of nuclear fusion energy will require materials that can withstand high doses of neutron irradiation, and one class of candidate materials for structural applications is reduced-activation ferritic-martensitic (RAFM) steels containing around 9% Cr. The present lack of a fusion neutron source has meant that much of the research into radiation damage has been conducted using specimens irradiated in fission test reactors, or by using heavy ion irradiation as a simulation method. This work explores details of the use of this emulation technique, alongside the effect of composition and impurities on radiation damage in these materials. Beam rastering is often employed during heavy ion irradiation in order to deliver a more uniform dose across the target area in comparison to continuous irradiation with a defocused beam, but this practice has been reported to alter the radiation-induced microstructural changes. This work investigated this in Fe and Fe-Cr alloys, using nanoindentation. No difference in post-irradiation hardness was observed between samples irradiated with a rastered or defocussed beam. A direct comparison of the microstructure and mechanical properties of heavy ion and neutron irradiated Fe-9Cr samples was made, and it was found that the segregation to dislocation loops and clustering of impurity elements Si and P reported in the neutron irradiated specimen was also present in the ion irradiated specimen. The α' precipitation reported after neutron irradiation did not occur after ion irradiation. The post-irradiation increase in hardness and yield stress of both samples were found to be the same, measured by nanoindentation and microcantilever testing. An increase in hardness of 0:88 ± 0:21 and 0:81 ± 0:26 GPa was found in the ion and neutron irradiated specimens respectively. The increase in hardness for the neutron irradiated specimen was found to be less then the 1:5 ± 0:28 GPa reported for an identically irradiated Fe-6Cr sample. The impact of carbon concentration on irradiation hardening in Fe was investigated by ion irradiating a high purity Fe sample containing regions of varying carbon concentration. Two samples were irradiated at two different dose rates, but no dose rate effect was observed. The increase in hardness however was found to increase with increasing carbon concentration, with a maximum increase of around 3 times that observed in pure Fe. This work has identified some limitations of and future challenges for the use of heavy ion irradiation as a surrogate to neutron irradiation in the absence of a dedicated fusion materials testing facility.

Gastro-oesophageal reflux disease (GORD) and obesity are associated with frequent exacerbations and poor quality of life in asthmatics. Multiple mechanisms have been proposed for the effect of obesity, including modification of inflammation affecting epithelial cell proliferation and wound repair, while the role of GORD is poorly understood and proton pump inhibitor (PPI) are of variable efficacy. GORD might exert a deleterious effect by inducing vagal reflex, neuroinflammation and directly ( via microaspiration) triggering airway inflammation. Studies of reflux in animal models and human bronchial epithelial cell culture show varying impact on inflammation and airway remodelling. Footnotes This manuscript has recently been accepted for publication in the European Respiratory Journal . It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJ online. Please open or download the PDF to view this article. Conflict of interest: Dr PEROTIN has nothing to disclose. Conflict of interest: Dr Schofield has nothing to disclose. Conflict of interest: Dr Wilson has nothing to disclose. Conflict of interest: Dr Ward has nothing to disclose. Conflict of interest: Dr Brandsma has nothing to disclose. Conflict of interest: Dr Strazzeri has nothing to disclose. Conflict of interest: Dr Bansal has nothing to disclose. Conflict of interest: Dr Yang has nothing to disclose. Conflict of interest: Dr Rowe reports and a full time employee and shareholder of Janssen Pharmaceutical Companies of Johnson and Johnson. Conflict of interest: Miss Corfield has nothing to disclose. Conflict of interest: Dr Lutter has nothing to disclose. Conflict of interest: Prof. Shaw reports personal fees and non-financial support from AstraZeneca, personal fees from Boehringer Ingelheim, personal fees from Novartis, personal fees from Teva, personal fees from Circassia, and a grant from GSK, outside the submitted work. Conflict of interest: Dr Bakke reports personal fees from GSK, AZ, Novartis andTeva, outside the submitted work. Conflict of interest: MC have no conflict of interest to disclose. Conflict of interest: Dr Dahlen has nothing to disclose. Conflict of interest: Dr Fowler reports personal fees and non-financial support from AstraZeneca, grants and personal fees from Boehringer Ingelheim, personal fees from Novartis, personal fees from Teva, outside the submitted work. Conflict of interest: Dr Horvath reports personal fees from Astra Zeneca, Boehringer Ingelheim, Novartis, CSL, Chiesi, Roche, GSK, Berlin-Chemie and Sandoz, outside the submitted work. Conflict of interest: Dr Howarth reports personal fees from GSK, outside the submitted work. Conflict of interest: Dr Krug has nothing to disclose. Conflict of interest: Dr Montuschi has nothing to disclose. Conflict of interest: Dr Sanak has nothing to disclose. Conflict of interest: Dr Sandstrom reports other monetary support from Boehringer Ingelheim, outside the submitted work. Conflict of interest: Dr Sun has nothing to disclose. Conflict of interest: Dr Pandis has nothing to disclose. Conflict of interest: Dr Auffray reports grants from Innovative Medicine Initiative, during the conduct of the study. Conflict of interest: Dr De Meulder reports grants from Innovative Medicine Initiative, during the conduct of the study. Conflict of interest: Ms. Lefaudeux reports grants from Innovative Medicine Initiative, grants from Innovative Medicine Initiative, during the conduct of the study. Conflict of interest: Dr Riley reports and I have shares in and I am employed by GSK. Conflict of interest: Dr Sousa has nothing to disclose. Conflict of interest: Dr Dahlen has nothing to disclose. Conflict of interest: Dr Adcock reports grants from EU-IMI, during the conduct of the study. Conflict of interest: KFC has received honoraria for participating in Advisory Board meetings of GSK, AZ, BI, Teva, Novartis and Merck regarding treatments for asthma and chronic obstructive pulmonary disease and has also been renumerated for speaking engagements. Conflict of interest: Dr Sterk reports grants from Innovative Medicines Initiative, during the conduct of the study. Conflict of interest: Dr Skipp has nothing to disclose. Conflict of interest: Dr Collins reports a patent application for use of a genetically modified Drosophila line carrying one or more mammalian genes associated with a chronic respiratory disease and uses to screen the impact of such genes. Conflict of interest: Dr Davies has nothing to disclose. Conflict of interest: Dr Djukanovic reports receiving fees for lectures at symposia organised by Novartis, AstraZeneca and TEVA, consultation for TEVA and Novartis as member of advisory boards, and participation in a scientific discussion about asthma organised by GlaxoSmithKline. He is a co-founder and current consultant, and has shares in Synairgen, a University of Southampton spin out company.

Background Multilevel data integration is becoming a major area of research in systems biology. Within this area, multi-‘omics datasets on complex diseases are becoming more readily available and there is a need to set standards and good practices for integrated analysis of biological, clinical and environmental data. We present a framework to plan and generate single and multi-‘omics signatures of disease states. Methods The framework is divided into four major steps: dataset subsetting, feature filtering, ‘omics-based clustering and biomarker identification. Results We illustrate the usefulness of this framework by identifying potential patient clusters based on integrated multi-‘omics signatures in a publicly available ovarian cystadenocarcinoma dataset. The analysis generated a higher number of stable and clinically relevant clusters than previously reported, and enabled the generation of predictive models of patient outcomes. Conclusions This framework will help health researchers plan and perform multi-‘omics big data analyses to generate hypotheses and make sense of their rich, diverse and ever growing datasets, to enable implementation of translational P4 medicine. Electronic supplementary material The online version of this article (10.1186/s12918-018-0556-z) contains supplementary material, which is available to authorized users.

The p.N478D missense mutation in human mitochondrial poly(A) polymerase (mtPAP) has previously been implicated in a form of spastic ataxia with optic atrophy. In this study, we have investigated fibroblast cell lines established from family members. The homozygous mutation resulted in the loss of polyadenylation of all mitochondrial transcripts assessed; however, oligoadenylation was retained. Interestingly, this had differential effects on transcript stability that were dependent on the particular species of transcript. These changes were accompanied by a severe loss of oxidative phosphorylation complexes I and IV, and perturbation of de novo mitochondrial protein synthesis. Decreases in transcript polyadenylation and in respiratory chain complexes were effectively rescued by overexpression of wild-type mtPAP. Both mutated and wild-type mtPAP localized to the mitochondrial RNA-processing granules thereby eliminating mislocalization as a cause of defective polyadenylation. In vitro polyadenylation assays revealed severely compromised activity by the mutated protein, which generated only short oligo(A) extensions on RNA substrates, irrespective of RNA secondary structure. The addition of LRPPRC/SLIRP, a mitochondrial RNA-binding complex, enhanced activity of the wild-type mtPAP resulting in increased overall tail length. The LRPPRC/SLIRP effect although present was less marked with mutated mtPAP, independent of RNA secondary structure. We conclude that (i) the polymerase activity of mtPAP can be modulated by the presence of LRPPRC/SLIRP, (ii) N478D mtPAP mutation decreases polymerase activity and (iii) the alteration in poly(A) length is sufficient to cause dysregulation of post-transcriptional expression and the pathogenic lack of respiratory chain complexes.

Objective: To determine whether droxidopa, an oral norepinephrine precursor, improves symptomatic neurogenic orthostatic hypotension (nOH). Methods: Patients with symptomatic nOH due to Parkinson disease, multiple system atrophy, pure autonomic failure, or nondiabetic autonomic neuropathy underwent open-label droxidopa dose optimization (100–600 mg 3 times daily), followed, in responders, by 7-day washout and then a 7-day double-blind trial of droxidopa vs placebo. Outcome measures included patient self-ratings on the Orthostatic Hypotension Questionnaire (OHQ), a validated, nOH-specific tool that assesses symptom severity and symptom impact on daily activities. Results: From randomization to endpoint (n = 162), improvement in mean OHQ composite score favored droxidopa over placebo by 0.90 units (p = 0.003). Improvement in OHQ symptom subscore favored droxidopa by 0.73 units (p = 0.010), with maximum change in “dizziness/lightheadedness.” Improvement in symptom-impact subscore favored droxidopa by 1.06 units (p = 0.003), with maximum change for “standing a long time.” Mean standing systolic blood pressure (BP) increased by 11.2 vs 3.9 mm Hg (p < 0.001), and mean supine systolic BP by 7.6 vs 0.8 mm Hg (p < 0.001). At endpoint, supine systolic BP >180 mm Hg was observed in 4.9% of droxidopa and 2.5% of placebo recipients. Adverse events reported in ≥3% of double-blind droxidopa recipients were headache (7.4%) and dizziness (3.7%). No patients discontinued double-blind treatment because of adverse events. Conclusions: In patients with symptomatic nOH, droxidopa improved symptoms and symptom impact on daily activities, with an associated increase in standing systolic BP, and was generally well tolerated. Classification of evidence: This study provides Class I evidence that in patients with symptomatic nOH who respond to open-label droxidopa, droxidopa improves subjective and objective manifestation of nOH at 7 days.