The effect of surgical approach on the histology of the femoral head following resurfacing of the hip : analysis of retrieval specimens

Objectives: We aimed to determine the effect of surgical approach on the histology of the femoral head following resurfacing of the hip. Methods: We performed a histological assessment of the bone under the femoral component taken from retrieval specimens of patients having revision surgery following resurfacing of the hip. We compared the number of empty lacunae in specimens from patients who had originally had a posterior surgical approach with the number in patients having alternative surgical approaches. Results: We found a statistically significant increase in the percentage of empty lacunae in retrieval specimens from patients who had the posterior approach compared with other surgical approaches (p < 0.001). Conclusions: This indicates that the vascular compromise that occurs during the posterior surgical approach does have long-term effects on the bone of the femoral head, even if it does not cause overt avascular necrosis

Economic outcomes associated with deep surgical site infection in patients with an open fracture of the lower limb

Aims The aim of this study was to estimate economic outcomes associated with deep surgical site infection (SSI) in patients with an open fracture of the lower limb. Patients and Methods A total of 460 patients were recruited from 24 specialist trauma hospitals in the United Kingdom Major Trauma Network. Preference-based health-related quality-of-life outcomes, assessed using the EuroQol EQ-5D-3L and the 6-Item Short-Form Health Survey questionnaire (SF-6D), and economic costs (£, 2014/2015 prices) were measured using participant-completed questionnaires over the 12 months following injury. Descriptive statistics and multivariate regression analysis were used to explore the relationship between deep SSI and health utility scores, quality-adjusted life-years (QALYs), and health and personal social service (PSS) costs. Results Deep SSI was associated with lower EQ-5D-3L derived QALYs (adjusted mean difference -0.102, 95% confidence interval (CI) -0.202 to 0.001, p = 0.047) and increased health and social care costs (adjusted mean difference £1950; 95% CI £1383 to £5285, p = 0.250) versus patients without deep SSI over the 12 months following injury. Conclusion Deep SSI may lead to significantly impaired health-related quality of life and increased economic costs. Our economic estimates can be used to inform clinical and budgetary service planning and can act as reference data for future economic evaluations of preventive or treatment interventions

Discovery of Three Distant, Cold Brown Dwarfs in the WFC3 Infrared Spectroscopic Parallels Survey

We present the discovery of three late type (>T4) brown dwarfs, including a probable Y dwarf, in the WFC3 Infrared Spectroscopic Parallels (WISP) Survey. We use the G141 grism spectra to determine the spectral types of the dwarfs and derive distance estimates based on a comparison with nearby T dwarfs with known parallaxes. These are the most distant spectroscopically confirmed T/Y dwarfs, with the farthest at an estimated distance of ~400 pc. We compare the number of cold dwarfs found in the WISP survey with simulations of the brown dwarf mass function. The number found is generally consistent with an initial stellar mass function dN/dM \propto M^{-\alpha} with \alpha = 0.0--0.5, although the identification of a Y dwarf is somewhat surprising and may be indicative of either a flatter absolute magnitude/spectral type relation than previously reported or an upturn in the number of very late type brown dwarfs in the observed volume.Comment: Accepted for publication by ApJ Letters. 10 pages, 2 figure

Standard wound management versus negative-pressure wound therapy in the treatment of adult patients having surgical incisions for major trauma to the lower limb — a two-arm parallel group superiority randomised controlled trial : protocol for Wound Healing in Surgery for Trauma (WHIST)

Introduction Patients with closed high-energy injuries associated with major trauma have surprisingly high rates of surgical site infection in incisions created during fracture fixation. One factor that may reduce the risk of surgical site infection is the type of dressing applied over the closed surgical incision. In this multicentre randomised clinical trial, negative-pressure wound therapy will be compared with standard dressings with outcomes of deep infection, quality of life, pain and disability. Methods and analysis Adult patients presenting to hospital within 72 hours of sustaining major trauma, requiring a surgical incision to treat a fractured lower limb, are eligible for inclusion. Randomisation, stratified by trial centre, open/closed fracture at presentation and Injury Severity Score (ISS) ≤15 versus ISS ≥16 will be administered via a secure web-based service using minimisation. The random allocation will be to either standard wound management or negative-pressure wound therapy. Trial participants will usually have clinical follow-up at the local fracture clinic for a minimum of 6 months, as per standard National Health Service practice. Diagnosis of deep infection will be recorded at 30 days. Functional, pain and quality of life outcome data will be collected using the Disability Rating Index, Douleur Neuropathique Questionnaire and Euroqol - 5 Dimension - 5 level (EQ-5D-5L) questionnaires at 3 months and 6 months postinjury. Further data will be captured on resource use and any late postoperative complications. Longer term outcomes will be assessed annually for 5 years and reported separately. Ethics and dissemination National Research Ethics Committee approved this study on 16 February 2016 16/WM/0006. The National Institute for Health Research Health Technology Assessment monograph and a manuscript to a peer-reviewed journal will be submitted on completion of this trial. The results of this trial will inform clinical practice on the clinical and cost-effectiveness of the treatment of this injury

MHC class II-restricted antigen presentation by plasmacytoid dendritic cells drives proatherogenic T cell immunity

Background—Plasmacytoid dendritic cells (pDCs) bridge innate and adaptive immune responses and are important regulators of immuno-inflammatory diseases. However, their role in atherosclerosis remains elusive. Methods and Results—Here, we used genetic approaches to investigate the role of pDCs in atherosclerosis. Selective pDC deficiency in vivo was achieved using CD11c-Cre × Tcf4–/flox bone marrow transplanted into Ldlr–/– mice. Compared with control Ldlr–/– chimeric mice, CD11c-Cre × Tcf4–/flox mice had reduced atherosclerosis levels. To begin to understand the mechanisms by which pDCs regulate atherosclerosis, we studied chimeric Ldlr–/– mice with selective MHCII deficiency on pDCs. Significantly, these mice also developed reduced atherosclerosis compared with controls without reductions in pDC numbers or changes in conventional DCs. MHCII-deficient pDCs showed defective stimulation of apolipoprotein B100–specific CD4+ T cells in response to native low-density lipoprotein, whereas production of interferon-α was not affected. Finally, the atheroprotective effect of selective MHCII deficiency in pDCs was associated with significant reductions of proatherogenic T cell–derived interferon-γ and lesional T cell infiltration, and was abrogated in CD4+ T cell–depleted animals. Conclusions—This study supports a proatherogenic role for pDCs in murine atherosclerosis and identifies a critical role for MHCII-restricted antigen presentation by pDCs in driving proatherogenic T cell immunity

Physical Properties of Emission-Line Galaxies at z ~ 2 from Near-Infrared Spectroscopy with Magellan FIRE

We present results from near-infrared spectroscopy of 26 emission-line galaxies at z ~ 2 obtained with the FIRE spectrometer on the Magellan Baade telescope. The sample was selected from the WISP survey, which uses the near-infrared grism of the Hubble Space Telescope Wide Field Camera 3 to detect emission-line galaxies over 0.3 < z < 2.3. Our FIRE follow-up spectroscopy (R~5000) over 1.0-2.5 micron permits detailed measurements of physical properties of the z~2 emission-line galaxies. Dust-corrected star formation rates for the sample range from ~5-100 M_sun yr-1. We derive a median metallicity for the sample of ~0.45 Z_sun, and the estimated stellar masses range from ~10^8.5 - 10^9.5 M_sun. The average ionization parameters measured for the sample are typically much higher than what is found for local star-forming galaxies. We derive composite spectra from the FIRE sample, from which we infer typical nebular electron densities of ~100-400 cm^-3. Based on the location of the galaxies and composite spectra on BPT diagrams, we do not find evidence for significant AGN activity in the sample. Most of the galaxies as well as the composites are offset in the BPT diagram toward higher [O III]/H-beta at a given [N II]/H-alpha, in agreement with other observations of z > 1 star-forming galaxies, but composite spectra derived from the sample do not show an appreciable offset from the local star-forming sequence on the [O III]/H-beta versus [S II]/H-alpha diagram. We infer a high nitrogen-to-oxygen abundance ratio from the composite spectrum, which may contribute to the offset of the high-redshift galaxies from the local star-forming sequence in the [O III]/H-beta versus [N II]/H-alpha diagram. We speculate that the elevated nitrogen abundance could result from substantial numbers of Wolf-Rayet stars in starbursting galaxies at z~2. (Abridged)Comment: Accepted for publication in Ap

Intramedullary nail fixation versus locking plate fixation for adults with a fracture of the distal tibia : the UK FixDT RCT

Background The best treatment for fractures of the distal tibia remains controversial. Most of these fractures require surgical fixation, but the outcomes are unpredictable and complications are common. Objectives To assess disability, quality of life, complications and resource use in patients treated with intramedullary (IM) nail fixation versus locking plate fixation in the 12 months following a fracture of the distal tibia. Design This was a multicentre randomised trial. Setting The trial was conducted in 28 UK acute trauma centres from April 2013 to final follow-up in February 2017. Participants In total, 321 adult patients were recruited. Participants were excluded if they had open fractures, fractures involving the ankle joint, contraindication to nailing or inability to complete questionnaires. Interventions IM nail fixation (n = 161), in which a metal rod is inserted into the hollow centre of the tibia, versus locking plate fixation (n = 160), in which a plate is attached to the surface of the tibia with fixed-angle screws. Main outcome measures The primary outcome measure was the Disability Rating Index (DRI) score, which ranges from 0 points (no disability) to 100 points (complete disability), at 6 months with a minimum clinically important difference of 8 points. The DRI score was also collected at 3 and 12 months. The secondary outcomes were the Olerud–Molander Ankle Score (OMAS), quality of life as measured using EuroQol-5 Dimensions (EQ-5D), complications such as infection, and further surgery. Resource use was collected to inform the health economic evaluation. Results Participants had a mean age of 45 years (standard deviation 16.2 years), were predominantly male (61%, 197/321) and had experienced traumatic injury after a fall (69%, 223/321). There was no statistically significant difference in DRI score at 6 months [IM nail fixation group, mean 29.8 points, 95% confidence interval (CI) 26.1 to 33.7 points; locking plate group, mean 33.8 points, 95% CI 29.7 to 37.9 points; adjusted difference, 4.0 points, 95% CI –1.0 to 9.0 points; p = 0.11]. There was a statistically significant difference in DRI score at 3 months in favour of IM nail fixation (IM nail fixation group, mean 44.2 points, 95% CI 40.8 to 47.6 points; locking plate group, mean 52.6 points, 95% CI 49.3 to 55.9 points; adjusted difference 8.8 points, 95% CI 4.3 to 13.2 points; p < 0.001), but not at 12 months (IM nail fixation group, mean 23.1 points, 95% CI 18.9 to 27.2 points; locking plate group, 24.0 points, 95% CI 19.7 to 28.3 points; adjusted difference 1.9 points, 95% CI –3.2 to 6.9 points; p = 0.47). Secondary outcomes showed the same pattern, including a statistically significant difference in mean OMAS and EQ-5D scores at 3 and 6 months in favour of IM nail fixation. There were no statistically significant differences in complications, including the number of postoperative infections (13% in the locking plate group and 9% in the IM nail fixation group). Further surgery was more common in the locking plate group (12% in locking plate group and 8% in IM nail fixation group at 12 months). The economic evaluation showed that IM nail fixation provided a slightly higher quality of life in the 12 months after injury and at lower cost and, therefore, it was cost-effective compared with locking plate fixation. The probability of cost-effectiveness for IM nail fixation exceeded 90%, regardless of the value of the cost-effectiveness threshold. Limitations As wound dressings after surgery are clearly visible, it was not possible to blind the patients to their treatment allocation. This evidence does not apply to intra-articular (pilon) fractures of the distal tibia. Conclusions Among adults with an acute fracture of the distal tibia who were randomised to IM nail fixation or locking plate fixation, there were similar disability ratings at 6 months. However, recovery across all outcomes was faster in the IM nail fixation group and costs were lower

Reframing assessment research: through a practice perspective

Assessment as a field of investigation has been influenced by a limited number of perspectives. These have focused assessment research in particular ways that have emphasised measurement, or student learning or institutional policies. The aim of this paper is to view the phenomenon of assessment from a practice perspective drawing upon ideas from practice theory. Such a view places assessment practices as central. This perspective is illustrated using data from an empirical study of assessment decision-making and uses as an exemplar the identified practice of ‘bringing a new assessment task into being’. It is suggested that a practice perspective can position assessment as integral to curriculum practices and end separations of assessment from teaching and learning. It enables research on assessment to de-centre measurement and take account of the wider range of people, phenomena and things that constitute it

BAFF receptor deficiency reduces the development of atherosclerosis in mice--brief report.

OBJECTIVE: The goal of this study was to assess the role of B-cell activating factor (BAFF) receptor in B-cell regulation of atherosclerosis. METHODS AND RESULTS: Male LDL receptor-deficient mice (Ldlr(-/-)) were lethally irradiated and reconstituted with either wild type or BAFF receptor (BAFF-R)-deficient bone marrow. After 4 weeks of recovery, mice were put on a high-fat diet for 6 or 8 weeks. BAFF-R deficiency in bone marrow cells led to a marked reduction of conventional mature B2 cells but did not affect the B1a cell subtype. This was associated with a significant reduction of dendritic cell activation and T-cell proliferation along with a reduction of IgG antibodies against malondialdehyde-modified low-density lipoprotein. In contrast, serum IgM type antibodies were preserved. Interestingly, BAFF-R deficiency was associated with a significant reduction in atherosclerotic lesion development and reduced numbers of plaque T cells. Selective BAFF-R deficiency on B cells led to a similar reduction in lesion size and T-cell infiltration but in contrast did not affect dendritic cell activation. CONCLUSIONS: BAFF-R deficiency in mice selectively alters mature B2 cell-dependent cellular and humoral immune responses and limits the development of atherosclerosis.British Heart Foundation, Fondation Leducq.This is the author accepted manuscript. The final version is available from the American Heart Association at http://dx.doi.org/10.1161/ATVBAHA.111.244731

Enhanced weathering in the U.S. Corn Belt delivers carbon removal with agronomic benefits

Enhanced weathering (EW) with crushed basalt on farmlands is a promising scalable atmospheric carbon dioxide removal strategy that urgently requires performance assessment with commercial farming practices. Our large-scale replicated EW field trial in the heart of the U.S. Corn Belt shows cumulative time-integrated carbon sequestration of 15.4 +/- 4.1 t CO2 ha-1 over four years, with additional emissions mitigation of ~0.1 - 0.4 t CO2,e ha-1 yr-1 for soil nitrous oxide, a potent long-lived greenhouse gas. Maize and soybean yields increased 12-16% with EW following improved soil fertility, decreased soil acidification, and upregulation of root nutrient transport genes. Our findings suggest that widespread adoption of EW across farming sectors has the potential to contribute significantly to net-zero greenhouse gas emissions goals and global food and soil security