Reports of ChAdOx1 vaccine-associated thrombocytopenia and vascular adverse events have led to some countries restricting its use. Using a national prospective cohort, we estimated associations ...between exposure to first-dose ChAdOx1 or BNT162b2 vaccination and hematological and vascular adverse events using a nested incident-matched case-control study and a confirmatory self-controlled case series (SCCS) analysis. An association was found between ChAdOx1 vaccination and idiopathic thrombocytopenic purpura (ITP) (0-27 d after vaccination; adjusted rate ratio (aRR) = 5.77, 95% confidence interval (CI), 2.41-13.83), with an estimated incidence of 1.13 (0.62-1.63) cases per 100,000 doses. An SCCS analysis confirmed that this was unlikely due to bias (RR = 1.98 (1.29-3.02)). There was also an increased risk for arterial thromboembolic events (aRR = 1.22, 1.12-1.34) 0-27 d after vaccination, with an SCCS RR of 0.97 (0.93-1.02). For hemorrhagic events 0-27 d after vaccination, the aRR was 1.48 (1.12-1.96), with an SCCS RR of 0.95 (0.82-1.11). A first dose of ChAdOx1 was found to be associated with small increased risks of ITP, with suggestive evidence of an increased risk of arterial thromboembolic and hemorrhagic events. The attenuation of effect found in the SCCS analysis means that there is the potential for overestimation of the reported results, which might indicate the presence of some residual confounding or confounding by indication. Public health authorities should inform their jurisdictions of these relatively small increased risks associated with ChAdOx1. No positive associations were seen between BNT162b2 and thrombocytopenic, thromboembolic and hemorrhagic events.
The use of antenatal steroid therapy is common in pregnancy. In early pregnancy, steroids may be used in women for the treatment of recurrent miscarriage or fetal abnormalities such as congenital ...adrenal hyperplasia. In mid-late pregnancy, the antenatal administration of corticosteroids to expectant mothers in anticipation of preterm birth is one of the most important advances in perinatal medicine; antenatal corticosteroids are now standard care for pregnancies at risk of premature delivery in high- and middle-income countries. The widespread uptake of this therapy is due to a compelling body of evidence demonstrating improved neonatal outcomes following antenatal corticosteroid exposure, stemming most notably from corticosteroid-driven maturation of fetal pulmonary function. As we approach the 50th anniversary of landmark work in this area by Liggins and Howie, it is apparent that much remains to be understood with regards to how we might best apply antenatal corticosteroid therapy to improve pregnancy outcomes at both early and mid to late gestation.
Drawing on advances in laboratory science, pre-clinical and clinical studies, we performed a narrative review of the scientific literature to provide a timely update on the benefits, risks and uncertainties regarding antenatal corticosteroid use in pregnancy. Three, well-established therapeutic uses of antenatal steroids, namely recurrent miscarriage, congenital adrenal hyperplasia and preterm birth, were selected to frame the review.
Even the most well-established antenatal steroid therapies lack the comprehensive pharmacokinetic and dose-response data necessary to optimize dosing regimens. New insights into complex, tissue-specific corticosteroid signalling by genomic-dependent and independent mechanisms have not been used to inform corticosteroid treatment strategies. There is growing evidence that some fetal corticosteroid treatments are either ineffective, or may result in adverse outcomes, in addition to lasting epigenetic changes in a variety of homeostatic mechanisms. Nowhere is the need to better understand the intricacies of corticosteroid therapy better conveyed than in the findings of Althabe and colleagues who recently reported an increase in overall neonatal mortality and maternal morbidity in association with antenatal corticosteroid administration in low-resource settings.
New research to clarify the benefits and potential risks of antenatal corticosteroid therapy is urgently needed, especially with regard to corticosteroid use in low-resource environments. We conclude that there is both significant scope and an urgent need for further research-informed refinement to the use of antenatal corticosteroids in pregnancy.
Severe Acute Respiratory Syndrome coronavirus-2 (SARS-CoV-2) has challenged public health agencies globally. In order to effectively target government responses, it is critical to identify the ...individuals most at risk of coronavirus disease-19 (COVID-19), developing severe clinical signs, and mortality. We undertook a systematic review of the literature to present the current status of scientific knowledge in these areas and describe the need for unified global approaches, moving forwards, as well as lessons learnt for future pandemics.
Medline, Embase and Global Health were searched to the end of April 2020, as well as the Web of Science. Search terms were specific to the SARS-CoV-2 virus and COVID-19. Comparative studies of risk factors from any setting, population group and in any language were included. Titles, abstracts and full texts were screened by two reviewers and extracted in duplicate into a standardised form. Data were extracted on risk factors for COVID-19 disease, severe disease, or death and were narratively and descriptively synthesised.
One thousand two hundred and thirty-eight papers were identified post-deduplication. Thirty-three met our inclusion criteria, of which 26 were from China. Six assessed the risk of contracting the disease, 20 the risk of having severe disease and ten the risk of dying. Age, gender and co-morbidities were commonly assessed as risk factors. The weight of evidence showed increasing age to be associated with severe disease and mortality, and general comorbidities with mortality. Only seven studies presented multivariable analyses and power was generally limited. A wide range of definitions were used for disease severity.
The volume of literature generated in the short time since the appearance of SARS-CoV-2 has been considerable. Many studies have sought to document the risk factors for COVID-19 disease, disease severity and mortality; age was the only risk factor based on robust studies and with a consistent body of evidence. Mechanistic studies are required to understand why age is such an important risk factor. At the start of pandemics, large, standardised, studies that use multivariable analyses are urgently needed so that the populations most at risk can be rapidly protected.
This review was registered on PROSPERO as CRD42020177714 .
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Objective
To determine the risk of spontaneous and medically indicated preterm birth associated with mode of birth in previous term‐born pregnancy.
Design
Retrospective cohort study.
Setting
Two UK ...maternity units.
Population or sample
A total of 16 340 women with first two consecutive singleton births and the first birth at term.
Methods
Retrospective cohort study using routinely collected clinical data.
Main outcome measures
Incidence of spontaneous preterm birth and medically indicated preterm birth at less than 37 weeks of gestation after term birth, in relation to mode of birth in first pregnancy. Subgroup analysis on cervical dilatation at the time of first caesarean birth.
Results
Compared with vaginal birth, emergency caesarean birth at full dilatation was associated with an increase in spontaneous preterm birth (2.3% vaginal birth versus 4.5% full dilatation caesarean; adjusted odds ratio aOR 3.29, 95% CI 2.02–5.13, P < 0.001). Elective caesarean, emergency caesarean at <4 cm dilatation, and emergency caesarean at 4–9 cm dilatation were associated with increased medically indicated preterm birth (0.8% vaginal births versus 1.9% elective caesarean, 3.3% <4 cm caesarean, 1.3% 4–9 cm caesarean; aOR 2.30, 95% CI 1.19–4.15, P = 0.009; aOR 4.68, 95% CI 2.98–7.24, P < 0.001; and aOR 2.43, 95% CI 1.43–4.00, P = 0.001, respectively).
Conclusions
Term caesarean in the first stage of labour or performed prelabour is associated with medically indicated preterm birth. Term caesarean in the second stage of labour is associated with spontaneous preterm birth.
Tweetable
Caesarean in the second stage of labour is associated with spontaneous preterm birth.
Tweetable
Caesarean in the second stage of labour is associated with spontaneous preterm birth.
We report inelastic neutron scattering measurements on Na2IrO3, a candidate for the Kitaev spin model on the honeycomb lattice. We observe spin-wave excitations below 5 meV with a dispersion that can ...be accounted for by including substantial further-neighbor exchanges that stabilize zigzag magnetic order. The onset of long-range magnetic order below T(N)=15.3 K is confirmed via the observation of oscillations in zero-field muon-spin rotation experiments. Combining single-crystal diffraction and density functional calculations we propose a revised crystal structure model with significant departures from the ideal 90° Ir-O-Ir bonds required for dominant Kitaev exchange.
Context.
The nearby ultra-compact multiplanetary system YZ Ceti consists of at least three planets, and a fourth tentative signal. The orbital period of each planet is the subject of discussion in ...the literature due to strong aliasing in the radial velocity data. The stellar activity of this M dwarf also hampers significantly the derivation of the planetary parameters.
Aims.
With an additional 229 radial velocity measurements obtained since the discovery publication, we reanalyze the YZ Ceti system and resolve the alias issues.
Methods.
We use model comparison in the framework of Bayesian statistics and periodogram simulations based on a method by Dawson and Fabrycky to resolve the aliases. We discuss additional signals in the RV data, and derive the planetary parameters by simultaneously modeling the stellar activity with a Gaussian process regression model. To constrain the planetary parameters further we apply a stability analysis on our ensemble of Keplerian fits.
Results.
We find no evidence for a fourth possible companion. We resolve the aliases: the three planets orbit the star with periods of 2.02 d, 3.06 d, and 4.66 d. We also investigate an effect of the stellar rotational signal on the derivation of the planetary parameters, in particular the eccentricity of the innermost planet. Using photometry we determine the stellar rotational period to be close to 68 d and we also detect this signal in the residuals of a three-planet fit to the RV data and the spectral activity indicators. From our stability analysis we derive a lower limit on the inclination of the system with the assumption of coplanar orbits which is
i
min
= 0.9 deg. From the absence of a transit event with TESS, we derive an upper limit of the inclination of
i
max
= 87.43 deg.
Conclusions.
YZ Ceti is a prime example of a system where strong aliasing hindered the determination of the orbital periods of exoplanets. Additionally, stellar activity influences the derivation of planetary parameters and modeling them correctly is important for the reliable estimation of the orbital parameters in this specific compact system. Stability considerations then allow additional constraints to be placed on the planetary parameters.
Induction of labour (IOL) is one of the most commonly performed interventions in maternity care, with outpatient cervical ripening increasingly offered as an option for women undergoing IOL. The ...COVID-19 pandemic has changed the context of practice and the option of returning home for cervical ripening may now assume greater significance. This work aimed to examine whether and how the COVID-19 pandemic has changed practice around IOL in the UK.
We used an online questionnaire to survey senior obstetricians and midwives at all 156 UK NHS Trusts and Boards that currently offer maternity services. Responses were analysed to produce descriptive statistics, with free text responses analysed using a conventional content analysis approach.
Responses were received from 92 of 156 UK Trusts and Boards, a 59% response rate. Many Trusts and Boards reported no change to their IOL practice, however 23% reported change in methods used for cervical ripening; 28% a change in criteria for home cervical ripening; 28% stated that more women were returning home during cervical ripening; and 24% noted changes to women's response to recommendations for IOL. Much of the change was reported as happening in response to attempts to minimise hospital attendance and restrictions on birth partners accompanying women.
The pandemic has changed practice around induction of labour, although this varied significantly between NHS Trusts and Boards. There is a lack of formal evidence to support decision-making around outpatient cervical ripening: the basis on which changes were implemented and what evidence was used to inform decisions is not clear.
Dynamical histories of planetary systems, as well as the atmospheric evolution of highly irradiated planets, can be studied by characterizing the ultra-short-period planet population, which the TESS ...mission is particularly well suited to discover. Here, we report on the follow-up of a transit signal detected in the TESS sector 19 photometric time series of the M3.0 V star TOI-1685 (2MASS J04342248+4302148). We confirm the planetary nature of the transit signal, which has a period of
P
b
= 0.6691403
−0.0000021
+0.0000023
d, using precise radial velocity measurements taken with the CARMENES spectrograph. From the joint photometry and radial velocity analysis, we estimate the following parameters for TOI-1685 b: a mass of
M
b
= 3.78
−0.63
+0.63
M
⊕
, a radius of
R
b
= 1.70
−0.07
+0.07
R
⊕
, which together result in a bulk density of
ρ
b
= 4.21
−0.82
+0.95
g cm
−3
, and an equilibrium temperature of
T
eq
= 1069
−16
+16
K. TOI-1685 b is the least dense ultra-short-period planet around an M dwarf known to date. TOI-1685 b is also one of the hottest transiting super-Earth planets with accurate dynamical mass measurements, which makes it a particularly attractive target for thermal emission spectroscopy. Additionally, we report with moderate evidence an additional non-transiting planet candidate in the system, TOI-1685 c, which has an orbital period of
P
c
= 9.02
−0.12
+0.10
d.
Spectroscopy of transiting exoplanets can be used to investigate their atmospheric properties
and habitability. Combining radial velocity (RV) and transit data provides additional information
on ...exoplanet physical properties. We detect a transiting rocky planet with an orbital period
of 1.467 days around the nearby red dwarf star Gliese 486. The planet Gliese 486 b is
2.81 Earth masses and 1.31 Earth radii, with uncertainties of 5%, as determined from RV data
and photometric light curves. The host star is at a distance of ~8.1 parsecs, has a J-band magnitude of ~7.2, and is observable from both hemispheres of Earth. On the basis of these properties and the planet’s short orbital period and high equilibrium temperature, we show that this terrestrial planet is suitable for emission and transit spectroscopy.
PDF
