17 research outputs found

    Catching Element Formation In The Act

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    Gamma-ray astronomy explores the most energetic photons in nature to address some of the most pressing puzzles in contemporary astrophysics. It encompasses a wide range of objects and phenomena: stars, supernovae, novae, neutron stars, stellar-mass black holes, nucleosynthesis, the interstellar medium, cosmic rays and relativistic-particle acceleration, and the evolution of galaxies. MeV gamma-rays provide a unique probe of nuclear processes in astronomy, directly measuring radioactive decay, nuclear de-excitation, and positron annihilation. The substantial information carried by gamma-ray photons allows us to see deeper into these objects, the bulk of the power is often emitted at gamma-ray energies, and radioactivity provides a natural physical clock that adds unique information. New science will be driven by time-domain population studies at gamma-ray energies. This science is enabled by next-generation gamma-ray instruments with one to two orders of magnitude better sensitivity, larger sky coverage, and faster cadence than all previous gamma-ray instruments. This transformative capability permits: (a) the accurate identification of the gamma-ray emitting objects and correlations with observations taken at other wavelengths and with other messengers; (b) construction of new gamma-ray maps of the Milky Way and other nearby galaxies where extended regions are distinguished from point sources; and (c) considerable serendipitous science of scarce events -- nearby neutron star mergers, for example. Advances in technology push the performance of new gamma-ray instruments to address a wide set of astrophysical questions.Comment: 14 pages including 3 figure

    Does the impact of COVID-19 on patients with systemic sclerosis change over time?

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    Objective: The outcome of patients with COVID-19 improved over the pandemic, including patients with systemic rheumatic diseases. However, data on patients with systemic sclerosis (SSc) are lacking. This study aimed to assess the outcome of patients with both SSc and COVID-19 over several waves. Methods: Patients with both SSc and COVID-19 who were registered in the European Scleroderma Trials and Research group (EUSTAR) were collected between April 2020 and April 2021. Patients were assigned to waves 1, 2, or 3 depending on the date of their COVID-19 diagnosis. Primary endpoints were death, intensive care unit stay, or ventilatory support (severe outcome). Subgroup analyses of patients who were hospitalized or died were conducted. General and SSc-specific characteristics and treatment were compared over the waves. Descriptive statistics and multivariate logistic regression were applied. Results: A total of 333 patients were included; 57 patients (17%) had a severe outcome, and 30 patients (9%) died. Compared to wave 1, significantly fewer patients with SSc suffered from severe COVID-19 in waves 2 and 3 (28.2% vs 9.8% and 12.7%; P < 0.001), fewer patients required hospitalization (46.7% vs 19.6% and 25.5%; P < 0.001) or ventilatory support (24.0% vs 8.7% and 10.9%; P = 0.001), and fewer patients died (15.7% vs 5.0% and 7.5%; P = 0.011). Patients were significantly younger, more often men, had less frequent arterial hypertension, and less SSc cardiac involvement over waves 1 to 3. Patients received significantly less medium to high doses of corticosteroids as they did SSc treatment. Conclusion: The outcome of patients with both SSc and COVID-19 improved significantly over time because of intrinsic and extrinsic factors

    Adequate vs. deep response to UDCA in PBC: To what extent and under what conditions is normal ALP level associated with complication-free survival gain?

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    BACKGROUND AND AIMS: Normal alkaline phosphatase (ALP) levels in ursodeoxycholic acid (UDCA)-treated patients with primary biliary cholangitis (PBC) are associated with better long-term outcome. However, second-line therapies are currently recommended only when ALP levels remain above 1.5 times the upper limit of normal (xULN) after 12-month UDCA. We assessed whether, in patients considered good responders to UDCA, normal ALP levels were associated with significant survival gains. APPROACH AND RESULTS: We performed a retrospective cohort study of 1,047 patients with PBC who attained an adequate response to UDCA according to Paris-2 criteria. Time to liver-related complications, liver transplantation or death was assessed using adjusted restricted mean survival time analysis. The overall incidence rate of events was 17.0 (95%CI 13.7 - 21.1) per 1,000 out of 4,763.2 patient-years. On the whole population, normal serum ALP values (but not normal GGT, ALT, or AST; or total bilirubin < 0.6 xULN) were associated with an overall absolute complication-free survival gain at 10 years of 7.6 months (95%CI 2.7 - 12.6, p = 0.003). In subgroup analysis, this association was significant in patients with a liver stiffness measurement ≄ 10 kPa and/or age ≀ 62 years, with a 10-year absolute complication-free survival gain of 52.8 months (95%CI 45.7 - 59.9, p < 0.001) when these two conditions were met. CONCLUSIONS: PBC patients with an adequate response to UDCA and persistent ALP elevation between 1.1 and 1.5 xULN, particularly those with advanced fibrosis and/or who are sufficiently young, remain at risk of poor outcome. Further therapeutic efforts should be considered for these patients

    Does the impact of COVID-19 on patients with systemic sclerosis change over time?

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    OBJECTIVE Outcome of COVID-19 patients improved over the pandemic, including patients with systemic rheumatic diseases. However, data on systemic sclerosis (SSc) patients are lacking. This study aimed to assess the outcome of SSc patients with COVID-19 over several waves. METHODS SSc patients with COVID-19 registered in the European Scleroderma Trials and Research group (EUSTAR) were collected between April 2020 and April 2021. Patients were assigned to wave 1 to 3 depending on date of COVID-19. Primary endpoints were death, intensive care unit stay or ventilatory support (severe outcome). Subgroup analyses of patients who were hospitalized or died were conducted. General and SSc-specific characteristics and treatment were compared over the waves. Descriptive statistics and multivariate logistic regression were applied. RESULTS 333 patients were included; 57 patients (17%) had a severe outcome, and 30 patients died (9%). Compared to wave 1, significantly fewer SSc patients suffered from severe COVID-19 in wave 2 and 3 (28.2% vs. 9.8% and 12.7%; p<0.001), less patients required hospitalization (46.7% vs. 19.6% and 25.5%; p<0.001) or ventilatory support (24.0% vs. 8.7% and 10.9%; p=0.001) and fewer patients died (15.7% vs. 5.0% and 7.5%; p=0.011). Patients were significantly younger, more often male, had less frequently arterial hypertension and less SSc cardiac involvement over wave 1 to 3. Patients received significantly less medium to high dose corticosteroids as SSc treatment. CONCLUSIONS Outcome of SSc patients with COVID-19 improved significantly over time, due to intrinsic and extrinsic factors. This article is protected by copyright. All rights reserved

    Contribution of Liver Stiffness Measurement by Vibration-Controlled Transient Elastography to Outcome Prediction in Primary Biliary Cholangitis

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    International audienceBackground & aims: Liver stiffness measurement (LSM) by vibration-controlled transient elastography (VCTE) has been shown to predict outcomes of patients with primary biliary cholangitis (PBC) in small-size studies. We aimed to validate the prognostic value of LSM in a large cohort study.Methods: We performed an international, multicentre, retrospective follow-up study of 3,985 patients with PBC seen at 23 centres in 12 countries. Eligibility criteria included at least 1 reliable LSM by VCTE and a follow-up ≄ 1 year. Independent derivation (n = 2,740) and validation (n = 568) cohorts were built. The primary endpoint was time to poor clinical outcomes defined as liver-related complications, liver transplantation, or death. Hazard ratios (HRs) with CIs were determined using a time-dependent multivariable Cox regression analysis.Results: LSM was independently associated with poor clinical outcomes in the derivation (5,324 LSMs, mean follow-up 5.0 ± 3.1 years) and validation (1,470 LSMs, mean follow-up 5.0 ± 2.8 years) cohorts: adjusted HRs (95% CI) per additional kPa were 1.040 (1.026-1.054) and 1.042 (1.029-1.056), respectively (p <0.0001 for both). Adjusted C-statistics (95% CI) at baseline were 0.83 (0.79-0.87) and 0.92 (0.89-0.95), respectively. Between 5 and 30 kPa, the log-HR increased as a monotonic function of LSM. The predictive value of LSM was stable in time. LSM improved the prognostic ability of biochemical response criteria, fibrosis scores, and prognostic scores. The 8 kPa and 15 kPa cut-offs optimally separated low-, medium-, and high-risk groups. Forty percent of patients were at medium to high risk according to LSM.Conclusions: LSM by VCTE is a major, independent, validated predictor of PBC outcome. Its value as a surrogate endpoint for clinical benefit in PBC should be considered.Lay summary: Primary biliary cholangitis (PBC) is a chronic autoimmune disease, wherein the body's immune system mistakenly attacks the bile ducts. PBC progresses gradually, so surrogate markers (markers that predict clinically relevant outcomes like the need for a transplant or death long before the event occurs) are often needed to expedite the drug development and approval process. Herein, we show that liver stiffness measurement is a strong predictor of clinical outcomes and could be a useful surrogate endpoint in PBC trials

    Adequate versus deep response to ursodeoxycholic acid in primary biliary cholangitis:To what extent and under what conditions is normal alkaline phosphatase level associated with complication-free survival gain?

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    Background and Aims: Normal alkaline phosphatase (ALP) levels in ursodeoxycholic acid (UDCA)-treated patients with primary biliary cholangitis (PBC) are associated with better long-term outcome. However, second-line therapies are currently recommended only when ALP levels remain above 1.5 times the upper limit of normal (×ULN) after 12-month UDCA. We assessed whether, in patients considered good responders to UDCA, normal ALP levels were associated with significant survival gains. Approach and Results: We performed a retrospective cohort study of 1047 patients with PBC who attained an adequate response to UDCA according to Paris-2 criteria. Time to liver-related complications, liver transplantation, or death was assessed using adjusted restricted mean survival time (RMST) analysis. The overall incidence rate of events was 17.0 (95% CI: 13.7-21.1) per 1000 out of 4763.2 patient-years. On the whole population, normal serum ALP values (but not normal gamma-glutamyl transpeptidase (GGT), alanine aminotransferase (ALT), or aspartate aminotransferase (AST); or total bilirubin &lt; 0.6 ×ULN) were associated with a significant absolute complication-free survival gain at 10 years (mean 7.6 months, 95% CI: 2.7 - 12.6 mo.; p = 0.003). In subgroup analysis, this association was significant in patients with a liver stiffness measurement ≄ 10 kPa and/or age ≀ 62 years, with a 10-year absolute complication-free survival gain of 52.8 months (95% CI: 45.7-59.9, p &lt; 0.001) when these 2 conditions were met. Conclusions: PBC patients with an adequate response to UDCA and persistent ALP elevation between 1.1 and 1.5 ×ULN, particularly those with advanced fibrosis and/or who are sufficiently young, remain at risk of poor outcome. Further therapeutic efforts should be considered for these patients.</p
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