Nanoscale imaging of Fe-rich inclusions in single-crystal zircon using X-ray ptycho-tomography

We apply X-ray ptycho-tomography to perform high-resolution, non-destructive, three-dimensional (3D) imaging of Fe-rich inclusions in paleomagnetically relevant materials (zircon single crystals from the Bishop Tuff ignimbrite). Correlative imaging using quantum diamond magnetic microscopy combined with X-ray fluorescence mapping was used to locate regions containing potential ferromagnetic remanence carriers. Ptycho-tomographic reconstructions with voxel sizes 85 nm and 21 nm were achievable across a field-of-view > 80 µm; voxel sizes as small as 5 nm were achievable over a limited field-of-view using local ptycho-tomography. Fe-rich inclusions 300 nm in size were clearly resolved. We estimate that particles as small as 100 nm—approaching single-domain threshold for magnetite—could be resolvable using this “dual-mode” methodology. Fe-rich inclusions (likely magnetite) are closely associated with apatite inclusions that have no visible connection to the exterior surface of the zircon (e.g., via intersecting cracks). There is no evidence of radiation damage, alteration, recrystallisation or deformation in the host zircon or apatite that could provide alternative pathways for Fe infiltration, indicating that magnetite and apatite grew separately as primary phases in the magma, that magnetite adhered to the surfaces of the apatite, and that the magnetite-coated apatite was then encapsulated as primary inclusions within the growing zircon. Rarer examples of Fe-rich inclusions entirely encapsulated by zircon are also observed. These observations support the presence of primary inclusions in relatively young and pristine zircon crystals. Combining magnetic and tomography results we deduce the presence of magnetic carriers that are in the optimal size range for carrying strong and stable paleomagnetic signals but that remain below the detection limits of even the highest-resolution X-ray tomography reconstructions. We recommend the use of focused ion beam nanotomography and/or correlative transmission electron microscopy to directly confirm the presence of primary magnetite in the sub 300 nm range as a necessary step in targeted paleomagnetic workflows

Development of a UK core dataset for geriatric medicine research: : a position statement and results from a Delphi consensus process

Funding AS and MW are funded by the Newcastle National Institute for Health (NIHR) Biomedical Research Centre, which also funded the initial meeting of academic clinicians in geriatric medicine during the Delphi process. The views expressed in this article are those of the authors and not necessarily those of the NIHR, the NHS, or the Department of Health. Acknowledgements The authors acknowledge the contributions of members of the UK Geriatric Medicine Core Dataset Extended Working Group.Peer reviewedPublisher PD

Cell salvage and donor blood transfusion during cesarean section: A pragmatic, multicentre randomised controlled trial (SALVO)

BACKGROUND: Excessive haemorrhage at cesarean section requires donor (allogeneic) blood transfusion. Cell salvage may reduce this requirement. METHODS AND FINDINGS: We conducted a pragmatic randomised controlled trial (at 26 obstetric units; participants recruited from 4 June 2013 to 17 April 2016) of routine cell salvage use (intervention) versus current standard of care without routine salvage use (control) in cesarean section among women at risk of haemorrhage. Randomisation was stratified, using random permuted blocks of variable sizes. In an intention-to-treat analysis, we used multivariable models, adjusting for stratification variables and prognostic factors identified a priori, to compare rates of donor blood transfusion (primary outcome) and fetomaternal haemorrhage ≥2 ml in RhD-negative women with RhD-positive babies (a secondary outcome) between groups. Among 3,028 women randomised (2,990 analysed), 95.6% of 1,498 assigned to intervention had cell salvage deployed (50.8% had salvaged blood returned; mean 259.9 ml) versus 3.9% of 1,492 assigned to control. Donor blood transfusion rate was 3.5% in the control group versus 2.5% in the intervention group (adjusted odds ratio [OR] 0.65, 95% confidence interval [CI] 0.42 to 1.01, p = 0.056; adjusted risk difference -1.03, 95% CI -2.13 to 0.06). In a planned subgroup analysis, the transfusion rate was 4.6% in women assigned to control versus 3.0% in the intervention group among emergency cesareans (adjusted OR 0.58, 95% CI 0.34 to 0.99), whereas it was 2.2% versus 1.8% among elective cesareans (adjusted OR 0.83, 95% CI 0.38 to 1.83) (interaction p = 0.46). No case of amniotic fluid embolism was observed. The rate of fetomaternal haemorrhage was higher with the intervention (10.5% in the control group versus 25.6% in the intervention group, adjusted OR 5.63, 95% CI 1.43 to 22.14, p = 0.013). We are unable to comment on long-term antibody sensitisation effects. CONCLUSIONS: The overall reduction observed in donor blood transfusion associated with the routine use of cell salvage during cesarean section was not statistically significant. TRIAL REGISTRATION: This trial was prospectively registered on ISRCTN as trial number 66118656 and can be viewed on http://www.isrctn.com/ISRCTN66118656

Cell salvage and donor blood transfusion during Caesarean section: a pragmatic multicentre randomised controlled trial (SALVO)

Background: Excessive haemorrhage at caesarean section requires donor (allogeneic) blood transfusion. Cell 34 salvage may reduce this requirement. Methods and findings: We conducted a pragmatic randomised controlled trial (26 obstetric units; June 2013 through April 2016) of routine cell salvage use (intervention) vs. current standard of care without routine salvage use (control) in caesarean section among women at risk of haemorrhage. Randomisation was stratified, using random permuted blocks of variable sizes. In an intention-to-treat analysis, we used multivariable models, adjusting for stratification variables and prognostic factors identified a priori, to compare rates of donor blood transfusion (primary outcome) and fetomaternal haemorrhage ≥2ml in RhD-negative women with RhD-positive baby (a secondary outcome) between groups. Among 3028 women randomised (2990 analysed), 95.6% of 1498 assigned to intervention had cell salvage deployed (50.8% had salvaged blood returned; mean 259.9 ml) vs. 3.9% of 1492 assigned to control. Donor blood transfusion rates were 3.5% in the control group vs. 2.5% in intervention (adjusted odds ratio [OR] 0.65, 95% confidence interval [CI] 0.42 to 1.01, p=0.056; adjusted risk difference -1.03, 95% CI -2.13 to 0.06; number needed to treat [NNT] 97, at the lower limit of 95% confidence NNT was 47 and at the upper limit the number needed to harm was 1,667). In a planned subgroup analysis, the transfusion rate was 4.6% in women assigned to control vs. 3.0% in the intervention group among emergency caesareans (adjusted OR 0.58, 95% CI 0.34 to 0.99), whereas it was 2.2% vs. 1.8% among elective caesareans (adjusted OR 0.83, 95% CI 0.38 to 1.83) (interaction p=0.46). No case of amniotic fluid embolism was observed. Fetomaternal haemorrhage was higher with intervention (10.5% in control vs. 25.6% in intervention, adjusted OR 5.63, 95% CI 1.43 to 22.14, p=0.013). We are unable to comment on long-term antibody sensitisation effects. Conclusions: The overall reduction observed in donor blood transfusion associated with the routine use of cell salvage during caesarean section was not statistically significant

Prevalence and factors associated with poor performance in the 5-chair stand test: findings from the Cognitive Function and Ageing Study II and proposed Newcastle protocol for use in the assessment of sarcopenia

Background: Poor performance in the 5-chair stand test (5-CST) indicates reduced lower limb muscle strength. The 5-CST has been recommended for use in the initial assessment of sarcopenia, the accelerated loss of muscle strength and mass. In order to facilitate the use of the 5-CST in sarcopenia assessment, our aims were to (i) describe the prevalence and factors associated with poor performance in the 5-CST, (ii) examine the relationship between the 5-CST and gait speed, and (iii) propose a protocol for using the 5-CST. Methods: The population-based study Cognitive Function and Ageing Study II recruited people aged 65 years and over from defined geographical localities in Cambridgeshire, Newcastle, and Nottingham. The study collected data for assessment of functional ability during home visits, including the 5-CST and gait speed. We used multinomial logistic regression to assess the associations between factors including the SARC-F questionnaire and the category of 5-CST performance: fast (15 s), or unable, with slow/unable classed as poor performance. We reviewed previous studies on the protocol used to carry out the 5-CST. Results: A total of 7190 participants aged 65+ from the three diverse localities of Cognitive Function and Ageing Study II were included (54.1% female). The proportion of those with poor performance in the 5-CST increased with age, from 34.3% at age 65–69 to 89.7% at age 90+. Factors independently associated with poor performance included positive responses to the SARC-F questionnaire, physical inactivity, depression, impaired cognition, and multimorbidity (all P < 0.005). Most people with poor performance also had slow gait speed (57.8%) or were unable to complete the gait speed test (18.4%). We found variation in the 5-CST protocol used, for example, timing until a participant stood up for the fifth time or until they sat down afterwards. Conclusions: Poor performance in the 5-CST is increasingly common with age and is associated with a cluster of other factors that characterize risk for poor ageing such as physical inactivity, impaired cognition, and multimorbidity. We recommend a low threshold for performing the 5-CST in clinical settings and provide a protocol for its use

New horizons in the role of digital data in the healthcare of older people

There are national and global moves to improve effective digital data design and application in healthcare. This New Horizons commentary describes the role of digital data in healthcare of the ageing population. We outline how health and social care professionals can engage in the proactive design of digital systems that appropriately serve people as they age, carers and the workforce that supports them

Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

Genome-wide survey of SNP variation uncovers the genetic structure of cattle breeds

status: publishe

Correction to: Cluster identification, selection, and description in Cluster randomized crossover trials: the PREP-IT trials

An amendment to this paper has been published and can be accessed via the original article