Transcriptional regulation of copper metabolism genes in the liver of fetal and neonatal control and iron-deficient rats

Acknowledgments The authors’ work is supported by Scottish Government (Rural and Environmental Scientific and Analytical Services). We are grateful to Ms Val Stevens for analytical and technical assistance and to the Biological Resource Facility staff for husbandry and maintenance of the experimental animals. The authors declare no conflicts of interest. Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.Peer reviewedPublisher PD

Use of a 3-item short-form version of the Barthel Index for use in stroke: systematic review and external validation

Background and Purpose—There may be a potential to reduce the number of items assessed in the Barthel Index (BI), and shortened versions of the BI have been described. We sought to collate all existing short-form BI (SF-BI) and perform a comparative validation using clinical trial data. Methods—We performed a systematic review across multidisciplinary electronic databases to find all published SF-BI. Our validation used the VISTA (Virtual International Stroke Trials Archive) resource. We describe concurrent validity (agreement of each SF-BI with BI), convergent and divergent validity (agreement of each SF-BI with other outcome measures available in the data set), predictive validity (association of prognostic factors with SF-BI outcomes), and content validity (item correlation and exploratory factor analyses). Results—From 3546 titles, we found 8 articles describing 6 differing SF-BI. Using acute trial data (n=8852), internal reliability suggested redundancy in BI (Cronbach α, 0.96). Each SF-BI demonstrated a strong correlation with BI, modified Rankin Scale, National Institutes of Health Stroke Scale (all ρ≥0.83; P<0.001). Using rehabilitation trial data (n=332), SF-BI demonstrated modest correlation with quality of life measures Stroke Impact Scale and 5 domain EuroQOL (ρ≥0.50, P<0.001). Prespecified prognostic factors were associated with SF-BI outcomes (all P<0.001). Our factor analysis described a 3 factor structure, and item reduction suggested an optimal 3-item SF-BI comprising bladder control, transfer, and mobility items in keeping with 1 of the 3-item SF-BI previously described in the literature. Conclusions—There is redundancy in the original BI; we have demonstrated internal and external validity of a 3-item SF-BI that should be simple to use

Structural and magnetic properties of the osmium double perovskites Ba2-xSrxYOsO6

The crystal and magnetic structures of double perovskites of the type Ba2-xSrxYOsO6 have been studied by synchrotron X-ray and neutron powder diffraction methods, bulk magnetic susceptibility measurements and X-ray absorption spectroscopy. The structures were refined using a combined neutron and synchrotron data set and are based on ordered array of corner sharing YO6 and OsO6 octahedra, with the Ba/Sr cations being completely disordered. The structure evolves from cubic to monoclinic as the Sr content is increased, due to the introduction of cooperative tilting of the octahedra. Bulk magnetic susceptibility measurements demonstrate the oxides are all antiferromagnets. The decrease in symmetry results in a, non-linear, increase in the Neel temperature. Low temperature neutron diffraction measurements of selected examples show these to be type-I antiferromagnets. X-ray absorption spectra collected at the Os L3- and L2-edges confirm the Os is pentavalent in all cases, and there is no detectable change in the covalency of the Os cation as the A-cation changes. Analysis of the L3:L2 branching ratio shows that the spin-orbit coupling is constant and insignificant across the series.Australian Synchrotron Australian Research Counci

Structure and phase transition in BaThO3: A combined neutron and synchrotron X-ray diffraction study

The structure of BaThO3, obtained by solid state synthesis, was refined for the first time by the Rietveld method using a combination of synchrotron X-ray and neutron powder diffraction data. BaThO3 has an orthorhombic structure at room temperature, in space group Pbnm with a = 6.3491(5), b = 6.3796(4) and c = 8.9907(7) Å. Heating BaThO3 to above 700 °C results in a continuous transition to a second orthorhombic structure, in space group Ibmm, demonstrated by both in situ neutron and synchrotron X-ray powder diffraction measurements. The coefficient of volumetric thermal expansion for BaThO3 is determined to be 1.04 x 10-5 oC-1 from 50 to 625 oC (Pbnm phase), and 9.43 x 10-6 oC-1 from 800 to 1000 oC (Ibmm phase). BaThO3 was found to decompose upon exposure to atmospheric moisture resulting in the formation of ThO2. The thermal expansion of ThO2, which invariably co-exists with BaThO3, is also described.Australian Synchrotron Australian Research Council2019-12-1

Glucose generates sub-plasma membrane ATP microdomains in single islet beta-cells. Potential role for strategically located mitochondria.

Abstract Increases in the concentration of free ATP within the islet β-cell may couple elevations in blood glucose to insulin release by closing ATP-sensitive K+(KATP) channels and activating Ca2+ influx. Here, we use recombinant targeted luciferases and photon counting imaging to monitor changes in free [ATP] in subdomains of single living MIN6 and primary β-cells. Resting [ATP] in the cytosol ([ATP]c), in the mitochondrial matrix ([ATP]m), and beneath the plasma membrane ([ATP]pm) were similar (∼1 mm). Elevations in extracellular glucose concentration (3–30 mm) increased free [ATP] in each domain with distinct kinetics. Thus, sustained increases in [ATP]m and [ATP]pm were observed, but only a transient increase in [ATP]c. However, detectable increases in [ATP]c and [ATP]pm, but not [ATP]m, required extracellular Ca2+. Enhancement of glucose-induced Ca2+ influx with high [K+] had little effect on the apparent [ATP]c and [ATP]m increases but augmented the [ATP]pm increase. Underlying these changes, glucose increased the mitochondrial proton motive force, an effect mimicked by high [K+]. These data support a model in which glucose increases [ATP]m both through enhanced substrate supply and by progressive Ca2+-dependent activation of mitochondrial enzymes. This may then lead to a privileged elevation of [ATP]pm, which may be essential for the sustained closure of KATP channels. Luciferase imaging would appear to be a useful new tool for dynamic in vivo imaging of free ATP concentration

Structure and phase transition in BaThO3: A combined neutron and synchrotron X-ray diffraction study

The structure of BaThO3, obtained by solid state synthesis, was refined for the first time by the Rietveld method using a combination of synchrotron X-ray and neutron powder diffraction data. BaThO3 has an orthorhombic structure at room temperature, in space group Pbnm with a = 6.3491(5), b = 6.3796(4) and c = 8.9907(7) Å. Heating BaThO3 to above 700 °C results in a continuous transition to a second orthorhombic structure, in space group Ibmm, demonstrated by both in situ neutron and synchrotron X-ray powder diffraction measurements. The coefficient of volumetric thermal expansion for BaThO3 is determined to be 1.04 x 10-5 oC-1 from 50 to 625 oC (Pbnm phase), and 9.43 x 10-6 oC-1 from 800 to 1000 oC (Ibmm phase). BaThO3 was found to decompose upon exposure to atmospheric moisture resulting in the formation of ThO2. The thermal expansion of ThO2, which invariably co-exists with BaThO3, is also described.Australian Synchrotron Australian Research Counci

Derivation and validation of a modified short form of the stroke impact scale

Background: The Stroke Impact Scale (SIS) is a stroke-specific, quality of life measure recommended for research and clinical practice. Completion rates are suboptimal and could relate to test burden. We derived and validated a short form-SIS. Methods and Results: We examined data from the Virtual International Stroke Trial Archive, generating derivation and validation populations. We derived a short form (SF-SIS) by selecting one item per domain of SIS, choosing items most highly correlated with total domain score. Our validation described agreement of SF-SIS with original SIS and the SIS-16, and correlation with Barthel Index, modified Rankin Scale, NIHSS, and EQ-5D visual analogue scales. We assessed discriminative validity, (associations between SF-SIS and factors known to influence outcome [age, physiological parameters and comorbidity]). We assessed face validity and acceptability by sharing the SF-SIS with a focus group of stroke survivors and multidisciplinary stroke healthcare staff. From 5549 acute study patients (mean age: 68.5 (SD:13) years; mean SIS :64 [SD:32]) and 332 rehabilitation patients (mean age 65.7 [SD:11]; mean SIS:61 [SD:11]), we derived an 8-item SF-SIS that demonstrated good agreement with original SIS and good correlation with our chosen functional and QOL measures (all rho>0.70; p<0.0001). Significant associations were seen with our chosen predictors of stroke outcome in the acute group (p<0.0001). The focus group agreed with the choice of items for SF-SIS across 7/8 domains. Conclusions: Using multiple, complementary methods we have derived a short form SIS and demonstrated content, convergent and discriminant validity. This shortened SIS should allow collection of robust quality of life data with less associated test burden