25 research outputs found

    Petrogenesis of Basalt-hosted sapphires from the Siebengebirge Volcanic Field (SVF) in western Germany

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    Megacysts of blue sapphires are hosted by alkaline mafic rocks from the Cenozoic Siebengebirge Volcanic Field (SVF) in western Germany. Similar occurrences of sapphires related to intra-continental alkaline mafic volcanism have been reported from many other localities around the world, predominantly from Asia and Australia (e.g. Graham et al., 2008). Markedly, the sapphires are rimmed by a several micrometer thick spinel rim, indicating them to be in disequilibrium with the basaltic melt. Consequently, the sapphires are regarded to be xenocrysts rather than phenocrysts. Yet, in-situ U-Pb dating of a columbite inclusion within one Siebengebirge sapphire using Laser Ablation – Inductively Coupled Plasma – Mass Spectrometry (LA-ICP-MS) revealed that the time of sapphire crystallization (24.73 ± 0.35 Ma) is within the errors the same as the age of alkaline mafic volcanism in the SVF (Przybyla, 2013), indicating a close genetical relationship between sapphire crystallization and alkaline mafic volcanism in the SVF. The sapphires mineral inclusion suite that is comprised amongst others of carbonates, pyrochlore, betafite and columbite, as well as the strong enrichment in the HFSE compared to the primitive mantle and the abundant occurrence of gaseous low-density CO2 inclusions, indicates that a carbonatitic melt played a major role in the sapphire formation. Glass inclusions of nephelinitic and of carbonated silicate composition probably represent the quenched products of two immiscible liquids in the silicate – carbonatite melt system, indicating that the crystallization of the sapphires was the result of complex magmatic processes in highly evolved SiO2 undersaturated, CO2-rich magmatic system, including extensive magma differentiation, the exsolution of two immiscible melts and the assimilation of the sapphire bearing host rocks by ascending fresh pulses of basaltic magma. Experiments that were conducted in the carbonatite – silicate melt system revealed that carbonatites are indeed eligible to precipitate corundum, given that the carbonatitic melts are saturated in Al2O3 and low in FeO and MgO. Yet, another set of experiments demonstrated that due to much better wetting propertied in a silicate melt, corundum that precipitated from a carbonatitic melt will always migrate into silicate melt if given the chance. Results from this study infer that the Siebengebirge sapphires probably crystallized from a highly evolved FeO- and MgO-deficient carbonatite that exsolved from a highly evolved phonolite as a consequence of increasing CO2 partial pressure accompanying melt fractionation. CO2-rich fluid inclusions have densities up to 0.9 g/cm3, infering that the sapphires must have formed at a minimum pressure of 0.6 GPa, corresponding to middle crustal levels. The sapphires were later trapped by fresh pulses of ascending alkaline mafic melts and subsequently transported to the surface. The process of sapphire trapping and transportation to the surface was very rapid on geological time-scales and lasted no longer than a few weeks to months, as indicated by the thickness of the spinel-rims. This petrogenetic scenario implies CO2 to be the confining variable connecting the genesis of the sapphire megacrysts and the alkaline mafic volcanism in intra-continental volcanic areas

    Stress hormones and verbal memory in young people over the first 12 weeks of treatment for psychosis

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    Aims Memory impairment in psychosis may be mediated through detrimental effects of hypothalamic-pituitary-adrenal (HPA) axis function. This study prospectively investigated the relationship between cortisol, sulphate dehydroepiandrosterone (DHEA(S) and cortisol: DHEA(S) ratio and memory in 35 first-episode psychosis (FEP) patients during the first 12 weeks of treatment and 23 healthy controls (HC). Methods Morning blood sampling and tests of attention, working memory and verbal memory occurred at baseline and 12-week follow-up. Results FEP and HC groups did not significantly differ in levels of cortisol, DHEA(S) or their ratio at baseline or over 12-weeks. The FEP group performed significantly below HC on all cognitive measures at baseline and over 12-weeks. Cortisol levels were unrelated to cognition in both groups. At baseline, DHEA(S) was positively associated with attention in HCs, but negatively associated with attention in FEP participants. Change in DHEA(S) was negatively associated with change in memory over 12-weeks in both groups. At 12-weeks, there was a negative correlation between the cortisol: DHEA(S) ratio and attention in both groups. Conclusions These findings are mostly in contrast to findings in chronic schizophrenia. Investigation at different illness phases and over longer-follow-up periods is required to determine the complex relationship between HPA-axis and memory functioning in psychosis

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    Robust estimation of bacterial cell count from optical density

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    Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

    Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

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    Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

    Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK.

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    BACKGROUND: A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials. METHODS: This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674. FINDINGS: Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0-75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4-97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8-80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3-4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation. INTERPRETATION: ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials. FUNDING: UK Research and Innovation, National Institutes for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, Bill & Melinda Gates Foundation, Lemann Foundation, Rede D'Or, Brava and Telles Foundation, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, and AstraZeneca

    Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK

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    Background A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials. Methods This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674. Findings Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0–75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4–97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8–80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3–4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation. Interpretation ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Increased endostatin generation and decreased angiogenesis via MMP-9 by tamoxifen in hormone dependent ovarian cancer

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    There are several similarities between breast and ovarian cancer but anti-estrogen treatment is rarely used in ovarian cancer. We have previously shown that the most widely used anti-estrogen tamoxifen increased MMP-9 activity and endostatin generation in breast cancer. Here, we show that tamoxifen exposure of highly hormone responsive ovarian cancer cells decreased proliferation, and increased MMP-9 activity leading to increased levels of endostatin both in cell culture in vitro and in solid tumors of nude mice. Tamoxifen exposed tumors also exhibited significantly decreased tumor growth and vascularisation. Moreover, in ascites from ovarian cancer patients, MMP-9 was undetectable in majority of cases but a significant correlation of MMP-2 and endostatin was found. The effects on MMPs and endostatin generation are previously unknown mechanisms of estradiol and tamoxifen in ovarian cancer, which may have therapeutic implications in future anti-cancer options of hormone dependent ovarian cancer.Original Publication:Christina Bendrik, Lisa Karlsson and Charlotta Dabrosin, Increased endostatin generation and decreased angiogenesis via MMP-9 by tamoxifen in hormone dependent ovarian cancer, 2010, CANCER LETTERS, (292), 1, 32-40.http://dx.doi.org/10.1016/j.canlet.2009.11.002Copyright: Elsevier Science B.V., Amsterdam.http://www.elsevier.com
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