Rationale, design and methodology of APPROACH-IS II: International study of patient-reported outcomes and frailty phenotyping in adults with congenital heart disease.

In recent years, patient-reported outcomes (PROs) have received increasing prominence in cardiovascular research and clinical care. An understanding of the variability and global experience of PROs in adults with congenital heart disease (CHD), however, is still lacking. Moreover, information on epidemiological characteristics and the frailty phenotype of older adults with CHD is minimal. The APPROACH-IS II study was established to address these knowledge gaps. This paper presents the design and methodology of APPROACH-IS II. APPROACH-IS II is a cross-sectional global multicentric study that includes Part 1 (assessing PROs) and Part 2 (investigating the frailty phenotype of older adults). With 53 participating centers, located in 32 countries across six continents, the aim is to enroll 8000 patients with CHD. In Part 1, self-report surveys are used to collect data on PROs (e.g., quality of life, perceived health, depressive symptoms, autonomy support), and explanatory variables (e.g., social support, stigma, illness identity, empowerment). In Part 2, the cognitive functioning and frailty phenotype of older adults are measured using validated assessments. APPROACH-IS II will generate a rich dataset representing the international experience of individuals in adult CHD care. The results of this project will provide a global view of PROs and the frailty phenotype of adults with CHD and will thereby address important knowledge gaps. Undoubtedly, the project will contribute to the overarching aim of improving optimal living and care provision for adults with CHD

Rivaroxaban Compared with Standard Anticoagulants for the Treatment of Acute Venous Thromboembolism in Children: a Randomised, Controlled, Phase 3 Trial

Background: Treatment of venous thromboembolism in children is based on data obtained in adults with little direct documentation of its efficacy and safety in children. The aim of our study was to compare the efficacy and safety of rivaroxaban versus standard anticoagulants in children with venous thromboembolism. Methods: In a multicentre, parallel-group, open-label, randomised study, children (aged 0–17 years) attending 107 paediatric hospitals in 28 countries with documented acute venous thromboembolism who had started heparinisation were assigned (2:1) to bodyweight-adjusted rivaroxaban (tablets or suspension) in a 20-mg equivalent dose or standard anticoagulants (heparin or switched to vitamin K antagonist). Randomisation was stratified by age and venous thromboembolism site. The main treatment period was 3 months (1 month in children <2 years of age with catheter-related venous thromboembolism). The primary efficacy outcome, symptomatic recurrent venous thromboembolism (assessed by intention-to-treat), and the principal safety outcome, major or clinically relevant non-major bleeding (assessed in participants who received ≥1 dose), were centrally assessed by investigators who were unaware of treatment assignment. Repeat imaging was obtained at the end of the main treatment period and compared with baseline imaging tests. This trial is registered with ClinicalTrials.gov, number NCT02234843 and has been completed. Findings: From Nov 14, 2014, to Sept 28, 2018, 500 (96%) of the 520 children screened for eligibility were enrolled. After a median follow-up of 91 days (IQR 87–95) in children who had a study treatment period of 3 months (n=463) and 31 days (IQR 29–35) in children who had a study treatment period of 1 month (n=37), symptomatic recurrent venous thromboembolism occurred in four (1%) of 335 children receiving rivaroxaban and five (3%) of 165 receiving standard anticoagulants (hazard ratio [HR] 0·40, 95% CI 0·11–1·41). Repeat imaging showed an improved effect of rivaroxaban on thrombotic burden as compared with standard anticoagulants (p=0·012). Major or clinically relevant non-major bleeding in participants who received ≥1 dose occurred in ten (3%) of 329 children (all non-major) receiving rivaroxaban and in three (2%) of 162 children (two major and one non-major) receiving standard anticoagulants (HR 1·58, 95% CI 0·51–6·27). Absolute and relative efficacy and safety estimates of rivaroxaban versus standard anticoagulation estimates were similar to those in rivaroxaban studies in adults. There were no treatment-related deaths. Interpretation: In children with acute venous thromboembolism, treatment with rivaroxaban resulted in a similarly low recurrence risk and reduced thrombotic burden without increased bleeding, as compared with standard anticoagulants. Funding: Bayer AG and Janssen Research & Development. © 2020 Elsevier Ltd

Kinetics of the OH + NO₂ reaction: rate coefficients (217-333 K, 16-1200 mbar) and fall-off parameters for N₂ and O₂ bath gases

The radical terminating, termolecular reaction between OH and NO2 exerts great influence on the NOy∕NOx ratio and O3 formation in the atmosphere. Evaluation panels (IUPAC and NASA) recommend rate coefficients for this reaction that disagree by as much as a factor of 1.6 at low temperature and pressure. In this work, the title reaction was studied by pulsed laser photolysis and laser-induced fluorescence over the pressure range 16–1200 mbar and temperature range 217–333 K in N2 bath gas, with experiments at 295 K (67–333 mbar) for O2. In situ measurement of NO2 using two optical absorption set-ups enabled generation of highly precise, accurate rate coefficients in the fall-off pressure range, appropriate for atmospheric conditions. We found, in agreement with previous work, that O2 bath gas has a lower collision efficiency than N2 with a relative collision efficiency to N2 of 0.74. Using the Troe-type formulation for termolecular reactions we present a new set of parameters with k0(N2) = 2.6×10−30  cm6 molecule−2 s−1, k0(O2) = 2.0×10−30 cm6 molecule−2 s−1, m=3.6, k∞=6.3×10−11 cm3 molecule−1 s−1, and Fc=0.39 and compare our results to previous studies in N2 and O2 bath gases

Reaction between CH₃C(O)OOH (peracetic acid) and OH in the gas-phase: A combined experimental and theoretical study of the kinetics and mechanism

Peracetic acid (CH3C(O)OOH) is one of the most abundant organic peroxides in the atmosphere, yet the kinetics of its reaction with OH, believed to be the major sink, have been studied only once experimentally. In this work we combine a pulsed-laser photolysis kinetic study of the title reaction with theoretical calculations of the rate coefficient and mechanism. We demonstrate that the rate coefficient is orders of magnitude lower than previously determined, with an experimentally derived upper limit of ≤ 4 × 10−14 cm3 molecule−1 s−1. The relatively low rate coefficient is in good agreement with the theoretical result of 3 × 10−14 cm3 molecule−1 s−1 at 298 K, increasing to ~ 6 × 10−14 in the cold upper troposphere, but with associated uncertainty of a factor-two. The reaction proceeds mainly via abstraction of the peroxidic-hydrogen via a relatively weakly bonded and short-lived pre-reaction complex, in which H-abstraction occurs only slowly due to a high barrier and low tunneling probabilities. Our results imply that the lifetime of CH3C(O)OOH with respect to OH-initiated degradation in the atmosphere is of the order of one year (and not days as previously believed) and that its major sink in the free and upper troposphere is likely to be photolysis, with dry-deposition important in the boundary layer. Similar conclusions can be made for other, saturated peroxy-acids

Kinetic and mechanistic study of the reaction between methane sulfonamide (CH₃S(O)₂NH₂) and OH

Methane sulfonamide (MSAM), CH3S(O)2NH2, was recently detected for the first time in ambient air over the Red Sea and the Gulf of Aden where peak mixing ratios of ≈ 60 pptv were recorded. Prior to this study the rate constant for its reaction with the OH radical and the products thereby formed were unknown, precluding assessment of its role in the atmosphere. We have studied the OH-initiated photo-oxidation of MSAM in air (298 K, 700 Torr total pressure) in a photochemical reactor using in situ detection of MSAM and its products by Fourier transform infrared (FTIR) absorption spectroscopy. The relative rate technique, using three different reference compounds, was used to derive a rate coefficient of (1.4 ± 0.3) x 10-13 cm3 molec.-1 s-1. The main end products of the photo-oxidation observed by FTIR were CO2, CO, SO2, and HNO3 with molar yields of (0.73 ± 0.11), (0.28 ± 0.04), (0.96 ± 0.15), and (0.62 ± 0.09), respectively. N2O and HC(O)OH were also observed in smaller yields of (0.09 ± 0.02) and (0.03 ± 0.01). Both the low rate coefficient and the products formed are consistent with hydrogen abstraction from the -CH3 group as the dominant initial step. Based on our results MSAM has an atmospheric lifetime with respect to loss by reaction with OH of about 80 d

Kinetics of the OH + NO₂ reaction: effect of water vapour and new parameterization for global modelling

The effect of water vapour on the rate coefficient for the atmospherically important, termolecular reaction between OH and NO2 was determined in He-H2O (277, 291, and 332 K) and N2-H2O bath gases (292 K). Combining pulsed-laser photolytic generation of OH and its detection by laser-induced fluorescence (PLP-LIF) with in situ, optical measurement of both NO2 and H2O, we were able to show that (in contrast to previous investigations) the presence of H2O increases the rate coefficient significantly. We derive a rate coefficient for H2O bath gas at the low-pressure limit (k0H2O) of 15.9 x 10-30 cm6 molecule-2 s-1. This indicates that H2O is a more efficient collisional quencher (by a factor of ≈ 6) of the initially formed HO-NO2 association complex than N2, and it is a factor of ≈ 8 more efficient than O2. Ignoring the effect of water vapour will lead to an underestimation of the rate coefficient by up to 15 %, e.g. in the tropical boundary layer. Combining the new experimental results from this study with those from our previous paper in which we report rate coefficients obtained in N2and O2 bath gases (Amedro et al., 2019), we derive a new parameterization for atmospheric modelling of the OH + NO2 reaction and use this in a chemical transport model (EMAC) to examine the impact of the new data on the global distribution of NO2, HNO2, and OH. Use of the new parameters (rather than those given in the IUPAC and NASA evaluations) results in significant changes in the HNO3/NO2 ratio and NOX concentrations (the sign of which depends on which evaluation is used as reference). The model predicts the presence of HOONO (formed along with HNO3 in the title reaction) in concentrations similar to those of HO2NO2 at the tropical tropopause

Impact of COVID-19 disease on clinical research in pediatric and congenital cardiology

International audienceBackground: COVID-19 triggered an unprecedented crisis affecting society at every level. Research in pediatric and congenital cardiology is currently in full development and may have been disrupted. The aim of the study was to determine the impact of COVID-19 on pediatric and congenital cardiology clinical research and to analyze decision-making and adaptation processes, from a panel of ongoing academic and industry-sponsored research at the time of the pandemic.Methods: This observational study was carried out in April 2020, from a CHD clinical research network involving five tertiary care pediatric and congenital cardiology centers. Investigators and clinical research assistants from each participating research center completed an online survey questionnaire, and each principal investigator underwent a 1-h web-based videoconference interview.Results: A total of 34 study questionnaires were collected, reporting that 18 studies were totally suspended. Upon the investigator's decision, after discussion on ethical issues and with facilitating support from health authorities, 16 studies were resumed. The rate of study suspension in interventional research (53%) was similar to that in non-interventional research (56%). Logistical problems were predominantly reported in both continued and suspended trials. Research protocols were adapted, largely thanks to telemedicine, which in some cases even improved the course of the study.Conclusion: The impact of the COVID-19 pandemic on clinical research in pediatric and congenital cardiology has been limited by a rapid adaptation of all research structures and an extensive use of telemedicine at all stages of the studies

Gas Phase Kinetics and Equilibrium of Allyl Radical Reactions with NO and NO 2

Article on gas phase kinetics and equilibrium of allyl radical reactions with NO and NO₂