39 research outputs found

    Effects of intrauterine exposure to synthetic glucocorticoids on fetal, newborn, and infant hypothalamic-pituitary-adrenal axis function in humans : a systematic review

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    BACKGROUND: Synthetic glucocorticoids are commonly used in reproductive medicine. Fetal organ systems are highly sensitive to changes in the intrauterine environment, including overexposure to glucocorticoids. Structural and functional alterations resulting from such changes may persist throughout life and have been associated with diverse diseases. One system that could be particularly sensitive to fetal glucocorticoid overexposure is the hypothalamic-pituitary-adrenal (hpa) axis. Many human studies have investigated this possibility, but a systematic review to identify consistent, emergent findings is lacking. METHODS: We systematically review 49 human studies, assessing the effects of intrauterine exposure to synthetic glucocorticoids on fetal, neonate, and infant hpa function. RESULTS: Study quality varied considerably, but the main findings held true after restricting the analyses to higher-quality studies: intrauterine exposure to synthetic glucocorticoids reduces offspring hpa activity under unstimulated conditions after pain but not pharmacological challenge. Although reduced unstimulated hpa function appears to recover within the first 2 wk postpartum, blunted hpa reactivity to pain is likely to persist throughout the first 4 months of life. There is some evidence that the magnitude of the effects is correlated with the total amount of glucocorticoids administered and varies with the time interval between glucocorticoid exposure and hpa assessment. CONCLUSIONS: This systematic review has allowed the demonstration of the way in which intrauterine exposure to various regimens of synthetic glucocorticoids affects various forms of hpa function. As such, it guides future studies in terms of which variables need to be focused on in order to further strengthen the understanding of such therapy, whilst continuing to profit from its clinical benefits

    Resonant two-site tunnelling dynamics of bosons in a tilted optical superlattice

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    We study the non-equilibrium dynamics of a 1D Bose-Hubbard model in a gradient potential and a superlattice, beginning from a deep Mott insulator regime with an average filling of one particle per site. Studying a quench that is near resonance to tunnelling of the particles over two lattice sites, we show how a spin model emerges consisting of two coupled Ising chains that are coupled by interaction terms in a staggered geometry. We compare and contrast the behavior in this case with that in a previously studied case where the resonant tunnelling was over a single site. Using optimized tensor network techniques to calculate finite temperature behavior of the model, as well as finite size scaling for the ground state, we conclude that the universality class of the phase transition for the coupled chains is that of a tricritical Ising point. We also investigate the out-of-equilibrium dynamics after the quench in the vicinity of the resonance and compare dynamics with recent experiments realized without the superlattice geometry. This model is directly realizable in current experiments, and reflects a new general way to realize spin models with ultracold atoms in optical lattices.Comment: 12 pages, 6 figure

    Antenatal and postnatal corticosteroid and resuscitation induced lung injury in preterm sheep

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    <p>Abstract</p> <p>Background</p> <p>Initiation of ventilation using high tidal volumes in preterm lambs causes lung injury and inflammation. Antenatal corticosteroids mature the lungs of preterm infants and postnatal corticosteroids are used to treat bronchopulmonary dysplasia.</p> <p>Objective</p> <p>To test if antenatal or postnatal corticosteroids would decrease resuscitation induced lung injury.</p> <p>Methods</p> <p>129 d gestational age lambs (n = 5-8/gp; term = 150 d) were operatively delivered and ventilated after exposure to either 1) no medication, 2) antenatal maternal IM Betamethasone 0.5 mg/kg 24 h prior to delivery, 3) 0.5 mg/kg Dexamethasone IV at delivery or 4) Cortisol 2 mg/kg IV at delivery. Lambs then were ventilated with no PEEP and escalating tidal volumes (<it>V</it><sub>T</sub>) to 15 mL/kg for 15 min and then given surfactant. The lambs were ventilated with <it>V</it><sub>T </sub>8 mL/kg and PEEP 5 cmH<sub>2</sub>0 for 2 h 45 min.</p> <p>Results</p> <p>High V<sub>T </sub>ventilation caused a deterioration of lung physiology, lung inflammation and injury. Antenatal betamethasone improved ventilation, decreased inflammatory cytokine mRNA expression and alveolar protein leak, but did not prevent neutrophil influx. Postnatal dexamethasone decreased pro-inflammatory cytokine expression, but had no beneficial effect on ventilation, and postnatal cortisol had no effect. Ventilation increased liver serum amyloid mRNA expression, which was unaffected by corticosteroids.</p> <p>Conclusions</p> <p>Antenatal betamethasone decreased lung injury without decreasing lung inflammatory cells or systemic acute phase responses. Postnatal dexamethasone or cortisol, at the doses tested, did not have important effects on lung function or injury, suggesting that corticosteroids given at birth will not decrease resuscitation mediated injury.</p

    Systemic hydrocortisone to prevent bronchopulmonary dysplasia in preterm infants (the SToP-BPD study); a multicenter randomized placebo controlled trial

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    <p>Abstract</p> <p>Background</p> <p>Randomized controlled trials have shown that treatment of chronically ventilated preterm infants after the first week of life with dexamethasone reduces the incidence of the combined outcome death or bronchopulmonary dysplasia (BPD). However, there are concerns that dexamethasone may increase the risk of adverse neurodevelopmental outcome. Hydrocortisone has been suggested as an alternative therapy. So far no randomized controlled trial has investigated its efficacy when administered after the first week of life to ventilated preterm infants.</p> <p>Methods/Design</p> <p>The SToP-BPD trial is a randomized double blind placebo controlled multicenter study including 400 very low birth weight infants (gestational age < 30 weeks and/or birth weight < 1250 grams), who are ventilator dependent at a postnatal age of 7 - 14 days. Hydrocortisone (cumulative dose 72.5 mg/kg) or placebo is administered during a 22 day tapering schedule. Primary outcome measure is the combined outcome mortality or BPD at 36 weeks postmenstrual age. Secondary outcomes are short term effects on the pulmonary condition, adverse effects during hospitalization, and long-term neurodevelopmental sequelae assessed at 2 years corrected gestational age. Analysis will be on an intention to treat basis.</p> <p>Discussion</p> <p>This trial will determine the efficacy and safety of postnatal hydrocortisone administration at a moderately early postnatal onset compared to placebo for the reduction of the combined outcome mortality and BPD at 36 weeks postmenstrual age in ventilator dependent preterm infants.</p> <p>Trial registration number</p> <p>Netherlands Trial Register (NTR): <a href="http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2768">NTR2768</a></p

    Tracheal left mainstem bronchus and obstructive gastric mucosal intussusception associated with esophageal atresia

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    A tracheal left mainstem bronchus and gastric outlet obstruction owing to gastric mucosal intussusception occurred in a child who had esophageal atresia and tracheoesophageal fistula. Bronchography and bronchoscopy, indicated because of persisting atelectasis and ventilation dependency, showed a tracheal left mainstem bronchus. The atelectasis disappeared after reimplantation of the left mainstem bronchus into the carina. Feeding problems and recurrent pulmonary infections complicated the postoperative course. Radiographic imaging and esophagogastroscopy showed severe reflux esophagitis and a prepyloric mass that consisted of a gastric mucosal intussusception. Subsequent gastrotomy and resection of the intussuscepted mucosal fold relieved the gastric outlet obstruction. An antireflux procedure was performed simultaneously. The child recovered satisfactorily. It is suggested that gastric mucosal intussusception may be associated with esophageal atresia rather than with the presence of a gastrostomy tube, as has been proposed in the literatur

    Changes in Survival and Neonatal Morbidity in Infants with a Birth Weight of 750 g or Less

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    Background: Improvement in perinatal and neonatal care has resulted in increased survival of extremely low birth weight (ELBW) infants. Objectives: To describe survival and neonatal morbidity in a cohort of ELBW infants, to compare two consecutive 5-year periods, and compare appropriate (AGA) with small for gestational age (SGA) infants (AGA >= p10, and SG

    Effect of Systemic Hydrocortisone Initiated 7 to 14 Days after Birth in Ventilated Preterm Infants on Mortality and Neurodevelopment at 2 Years' Corrected Age: Follow-up of a Randomized Clinical Trial

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    This follow-up to the STOP-BPD randomized clinical trial, which investigated the efficacy and safety of systemic hydrocortisone treatment initiated 7 to 14 days after birth in ventilator-dependent, very preterm infants in the Netherlands and Belgium at 36 weeksā€™ postmenstrual age, examines the prespecified composite of death and neurodevelopmental impairment among these infants at 2 yearsā€™ corrected age

    Effect of systemic hydrocortisone in ventilated preterm infants on parent-reported behavioural outcomes at 2 years' corrected age:Follow-up of a randomised clinical trial

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    Objective To report the parent-reported behavioural outcomes of infants included in the Systemic Hydrocortisone To Prevent Bronchopulmonary Dysplasia in preterm infants study at 2 years' corrected age (CA).Ā Design Randomised placebo-controlled trial.Ā Setting Dutch and Belgian neonatal intensive care units.Ā Patients Infants born &lt;30 weeks' gestation and/or birth weight &lt;1250 g, and ventilator dependent in the second week of life.Ā Intervention Infants were randomly assigned to a 22-day course of systemic hydrocortisone (cumulative dose 72.5 mg/kg; n=182) or placebo (n=190).Ā Main outcome measures Parent-reported behavioural outcomes at 2 years' CA assessed with the Child Behavior Checklist (CBCL 1Ā½-5).Ā Results Parents completed the CBCL of 183 (70% (183/262)) infants (hydrocortisone group, n=96; placebo group, n=87). Multiple imputation was used to account for missing data. Infants with critically elevated T-scores (&gt;55) were found in 22.9%, 19.1% and 29.4% of infants for total, internalising and externalising problems, respectively; these scores were not significantly different between groups (mean difference -1.52 (95% CI -4.00 to 0.96), -2.40 (95% CI -4.99 to 0.20) and -0.81 (95% CI -3.40 to 1.77), respectively). In the subscales, we found a significantly lower T-score for anxiety problems in the hydrocortisone group (mean difference -1.26, 95% CI -2.41 to -0.12).Ā Conclusion This study found high rates of behaviour problems at 2 years' CA following very preterm birth, but these problems were not associated with hydrocortisone treatment initiated between 7 and 14 days after birth in ventilated preterm infants.Ā Trial registration number NTR2768; EudraCT 2010-023777-19.</p
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