Search

Accurate estimate of fetal maturity could provide individualized guidance for delivery of complicated pregnancies. However, current methods are invasive, have low accuracy, and are limited to fetal lung maturation. To identify diagnostic gestational biomarkers, we performed transcriptomic profiling of lung and brain, as well as cell-free RNA from amniotic fluid of preterm and term rhesus macaque fetuses. These data identify potentially new and prior-associated gestational age differences in distinct lung and neuronal cell populations when compared with existing single-cell and bulk RNA-Seq data. Comparative analyses found hundreds of genes coincidently induced in lung and amniotic fluid, along with dozens in brain and amniotic fluid. These data enable creation of computational models that accurately predict lung compliance from amniotic fluid and lung transcriptome of preterm fetuses treated with antenatal corticosteroids. Importantly, antenatal steroids induced off-target gene expression changes in the brain, impinging upon synaptic transmission and neuronal and glial maturation, as this could have long-term consequences on brain development. Cell-free RNA in amniotic fluid may provide a substrate of global fetal maturation markers for personalized management of at-risk pregnancies. more...

Respiratory complicˆations are the major cause of morbidity and mortality among preterm infants, which is partially prevented by the administration of antenatal corticosteroids (ACS). Most very preterm infants are exposed to chorioamnionitis, but short- and long-term effects of ACS treatment in this setting are not well defined. In low-resource settings, ACS increased neonatal mortality by perhaps increasing infection. We report that treatment with low-dose ACS in the setting of inflammation induced by intraamniotic lipopolysaccharide (LPS) in rhesus macaques improves lung compliance and increases surfactant production relative to either exposure alone. RNA sequencing shows that these changes are mediated by suppression of proliferation and induction of mesenchymal cellular death via TP53. The combined exposure results in a mature-like transcriptomic profile with inhibition of extracellular matrix development by suppression of collagen genes COL1A1, COL1A2, and COL3A1 and regulators of lung development FGF9 and FGF10. ACS and inflammation also suppressed signature genes associated with proliferative mesenchymal progenitors similar to the term gestation lung. Treatment with ACS in the setting of inflammation may result in early respiratory advantage to preterm infants, but this advantage may come at a risk of abnormal extracellular matrix development, which may be associated with increased risk of chronic lung disease. more...

Antenatal corticosteroids (ANS) are the major intervention to decrease respiratory distress syndrome and mortality from premature birth and are standard of care. The use of ANS is expanding to include new indications and gestational ages, although the recommended dosing was never optimized. The most widely used treatment is two intramuscular doses of a 1:1 mixture of betamethasone-phosphate (Beta-P) and betamethasone-acetate (Beta-Ac) - the clinical drug. We tested in a primate model the efficacy of the slow release Beta-Ac alone for enhancing fetal lung maturation and to reduce fetal corticosteroid exposure and potential toxic effects. Pregnant rhesus macaques at 127 days of gestation (80% of term) were treated with either the clinical drug (0.25 mg/kg) or Beta-Ac (0.125 mg/kg). Beta-Ac alone increased lung compliance and surfactant concentration in the fetal lung equivalently to the clinical drug. By transcriptome analyses the early suppression of genes associated with immune responses and developmental pathways were less affected by Beta-Ac than the clinical drug. Promoter and regulatory analysis prediction identified differentially expressed genes targeted by the glucocorticoid receptor in the lung. At 5 days the clinical drug suppressed genes associated with neuronal development and differentiation in the fetal hippocampus compared to control, while low dose Beta-Ac alone did not. A low dose ANS treatment with Beta-Ac should be assessed for efficacy in human trials. more...

Antenatal corticosteroids (ACS) are standard of care for women at risk of preterm delivery, although choice of drug, dose or route have not been systematically evaluated. Further, ACS are infrequently used in low resource environments where most of the mortality from prematurity occurs. We report proof of principle experiments to test betamethasone-phosphate (Beta-P) or dexamethasone-phosphate (Dex-P) given orally in comparison to the clinical treatment with the intramuscular combination drug beta-phosphate plus beta-acetate in a Rhesus Macaque model. First, we performed pharmacokinetic studies in non-pregnant monkeys to compare blood levels of the steroids using oral dosing with Beta-P, Dex-P and an effective maternal intramuscular dose of the beta-acetate component of the clinical treatment. We then evaluated maternal and fetal blood steroid levels with limited fetal sampling under ultrasound guidance in pregnant macaques. We found that oral Beta is more slowly cleared from plasma than oral Dex. The blood levels of both drugs were lower in maternal plasma of pregnant than in non-pregnant macaques. Using the pharmacokinetic data, we treated groups of 6-8 pregnant monkeys with oral Beta-P, oral Dex-P, or the maternal intramuscular clinical treatment and saline controls and measured pressure-volume curves to assess corticosteroid effects on lung maturation at 5d. Oral Beta-P improved the pressure-volume curves similarly to the clinical treatment. Oral Dex-P gave more variable and nonsignificant responses. We then compared gene expression in the fetal lung, liver and hippocampus between oral Beta-P and the clinical treatment by RNA-sequencing. The transcriptomes were largely similar with small gene expression differences in the lung and liver, and no differences in the hippocampus between the groups. As proof of principle, ACS therapy can be effective using inexpensive and widely available oral drugs. Clinical dosing strategies must carefully consider the pharmacokinetics of oral Beta-P or Dex-P to minimize fetal exposure while achieving the desired treatment responses. more...

BackgroundAntenatal steroids are standard of care for women who are at risk of preterm delivery; however, antenatal steroid dosing and formulation have not been evaluated adequately. The standard clinical 2-dose treatment with betamethasone-acetate+betamethasone-phosphate is more effective than 2 doses of betamethasone-phosphate for the induction of lung maturation in preterm fetal sheep. We hypothesized that the slowly released betamethasone-acetate component induces similar lung maturation to betamethasone-phosphate+betamethasone-acetate with decreased dose and fetal exposure.ObjectiveThe purpose of this study was to investigate pharmacokinetics and fetal lung maturation of antenatal betamethasone-acetate in preterm fetal sheep.Study designGroups of 10 singleton-pregnant ewes received 1 or 2 intramuscular doses 24 hours apart of 0.25 mg/kg/dose of betamethasone-phosphate+betamethasone-acetate (the standard of care dose) or 1 intramuscular dose of 0.5 mg/kg, 0.25 mg/kg, or 0.125 mg/kg of betamethasone-acetate. Fetuses were delivered 48 hours after the first injection at 122 days of gestation (80% of term) and ventilated for 30 minutes, with ventilator settings, compliance, vital signs, and blood gas measurements recorded every 10 minutes. After ventilation, we measured static lung pressure-volume curves and sampled the lungs for messenger RNA measurements. Other groups of pregnant ewes and fetuses were catheterized and treated with intramuscular injections of betamethasone-phosphate 0.125 mg/kg, betamethasone-acetate 0.125 mg/kg, or betamethasone-acetate 0.5 mg/kg. Maternal and fetal betamethasone concentrations in plasma were measured for 24 hours.ResultsAll betamethasone-treated groups had increased messenger RNA expression of surfactant proteins A, B, and C, ATP-binding cassette subfamily A member 3, and aquaporin-5 compared with control animals. Treatment with 1 dose of intramuscular betamethasone-acetate 0.125mg/kg improved dynamic and static lung compliance, gas exchange, and ventilation efficiency similarly to the standard treatment of 2 doses of 0.25 m/kg of betamethasone-acetate+betamethasone-phosphate. Betamethasone-acetate 0.125 mg/kg resulted in lower maternal and fetal peak plasma concentrations and decreased fetal exposure to betamethasone compared with betamethasone-phosphate 0.125 mg/kg.ConclusionA single dose of betamethasone-acetate results in similar fetal lung maturation as the 2-dose clinical formulation of betamethasone-phosphate+betamethasone-acetate with decreased fetal exposure to betamethasone. A lower dose of betamethasone-acetate may be an effective alternative to induce fetal lung maturation with less risk to the fetus. more...

Bronchopulmonary dysplasia (BPD) and neurodevelopmental impairment are among the most common morbidities affecting preterm infants. Although BPD is a predictor of poor neurodevelopmental outcomes, it is currently uncertain how BPD contributes to brain injury in preterm infants. Extracellular vesicles (EVs) are involved in interorgan communication in diverse pathological processes. ASC (apoptosis-associated speck-like protein containing a caspase recruitment domain) is pivotal in inflammasome assembly and activation of inflammatory response. We assessed expression profiles of the alveolar macrophage (AM) markers CD11b, CD11c, and CD206 as well as ASC in EVs isolated from the plasma of preterm infants at risk for BPD at 1 week of age. We found that infants on higher fraction of inspired oxygen therapy (HO2⩾30%) had increased concentrations of AM-derived EV-ASC compared with infants on lower fraction of inspired oxygen (LO2<30%). To assess the function of these EVs, we performed adoptive transfer experiments by injecting them into the circulation of newborn mice. We discovered that mice that received EVs from infants on HO2 had increased lung inflammation, decreased alveolarization, and disrupted vascular development, the hallmarks of BPD. Importantly, these EVs crossed the blood–brain barrier, and the EVs from infants on HO2 caused inflammation, reduced cell survival, and increased cell death, with features of pyroptosis and necroptosis in the hippocampus. These results highlight a novel role for AM-derived EV-ASC in mediating the lung-to-brain cross-talk that is critical in the pathogenesis of BPD and brain injury and identify potential novel targets for preventing and treating BPD and brain injury in preterm infants. [ABSTRACT FROM AUTHOR] more...

BackgroundChorioamnionitis is associated with an increased risk of brain injury in preterm neonates. Inflammatory changes in brain could underlie this injury. Here, we evaluated whether neuroinflammation is induced by chorioamnionitis in a clinically relevant model.MethodsRhesus macaque fetuses were exposed to either intra-amniotic (IA) saline, or IA lipopolysaccharide (LPS) (1 mg) 16 or 48 h prior to delivery at 130 days (85 % of gestation) (n = 4-5 animals/group). We measured cytokines in the cerebrospinal fluid (CSF), froze samples from the left brain for molecular analysis, and immersion fixed the right brain hemisphere for immunohistology. We analyzed the messenger RNA (mRNA) levels of the pro-inflammatory cytokines IL-1β, CCL2, TNF-α, IL-6, IL-8, IL-10, and COX-2 in the periventricular white matter (PVWM), cortex, thalamus, hippocampus, and cerebellum by RT-qPCR. Brain injury was assessed by immunohistology for myelin basic protein (MBP), IBA1 (microglial marker), GFAP (astrocyte marker), OLIG2 (oligodendrocyte marker), NeuN (neuronal marker), CD3 (T cells), and CD14 (monocytes). Microglial proliferation was assessed by co-immunostaining for IBA1 and Ki67. Data were analyzed by ANOVA with Tukey's post-test.ResultsIA LPS increased mRNA expression of pro-inflammatory cytokines in the PVWM, thalamus, and cerebellum, increased IL-6 concentration in the CSF, and increased apoptosis in the periventricular area after 16 h. Microglial proliferation in the white matter was increased 48 h after IA LPS.ConclusionsLPS-induced chorioamnionitis caused neuroinflammation, microglial proliferation, and periventricular apoptosis in a clinically relevant model of chorioamnionitis in fetal rhesus macaques. These findings identify specific responses in the fetal brain and support the hypothesis that neuroinflammatory changes may mediate the adverse neurodevelopmental outcomes associated with chorioamnionitis. more...

BackgroundAlthough Ureaplasma species are the most common organisms associated with prematurity, their effects on the maternal and fetal immune system remain poorly characterized.MethodsRhesus macaque dams at approximately 80% gestation were injected intra-amniotically with 107 colony-forming units of Ureaplasma parvum or saline (control). Fetuses were delivered surgically 3 or 7 days later. We performed comprehensive assessments of inflammation and immune effects in multiple fetal and maternal tissues.ResultsAlthough U. parvum grew well in amniotic fluid, there was minimal chorioamnionitis. U. parvum colonized the fetal lung, but fetal systemic microbial invasion was limited. Fetal lung inflammation was mild, with elevations in CXCL8, tumor necrosis factor (TNF) α, and CCL2 levels in alveolar washes at day 7. Inflammation was not detected in the fetal brain. Significantly, U. parvum decreased regulatory T cells (Tregs) and activated interferon γ production in these Tregs in the fetus. It was detected in uterine tissue by day 7 and induced mild inflammation and increased expression of connexin 43, a gap junction protein involved with labor.ConclusionsU. parvum colonized the amniotic fluid and caused uterine inflammation, but without overt chorioamnionitis. It caused mild fetal lung inflammation but had a more profound effect on the fetal immune system, decreasing Tregs and polarizing them toward a T-helper 1 phenotype. more...

BackgroundDamage-associated molecular patterns (DAMPs) and antimicrobial peptides (AMPs) are components of pulmonary innate immunity and tissue repair. We hypothesized that DAMPs and AMPs would increase in response to fetal pulmonary inflammation caused by chorioamnionitis in a time-dependent manner.MethodsFetal sheep were exposed to intra-amniotic saline or lipopolysaccharide (LPS) (10 mg) between 5 h and 15 d prior to preterm delivery at 125 ± 2 d. Lung tissue mRNAs for proinflammatory cytokines; AMPs: myeloid AMP-29 (MAP29), dodecapeptide, sheep β-defensin-1 (SBD1), and sheep β-defensin-2 (SBD2); and DAMPs: interleukin (IL)-1α, lactoferrin, heat-shock protein-70 (HSP70), high-mobility group box protein-B1 (HMGB1), and receptor for advanced glycation endproducts (RAGE) were measured by reverse-transcriptase quantitative polymerase chain reaction. Immunohistochemistry of DAMPs and in situ hybridization of AMPs was performed.ResultsIL-1α, IL-1β, IL-6, IL-8, IL-10, MCP-1, and tumor necrosis factor (TNF)-α mRNA increased after LPS exposure. MAP29, dodecapeptide, SBD1, and SBD2 mRNA were suppressed at 24 h. MAP29 and dodecapeptide mRNA then increased at 8 d. Lactoferrin increased at 24 h. There were no changes for HMGB1, HSP70, or RAGE. MAP29 and dodecapeptide localized to alveolar cells, increased 8 d after exposure to LPS.ConclusionAMPs are initially suppressed in the fetal lung by LPS-induced chorioamnionitis. The late induction of MAP29 and dodecapeptide may be related to lung repair. more...

Background: Intra-amniotic inflammation (IAI) is associated with increased risk of preterm birth and bronchopulmonary dysplasia (BPD), but the mechanisms by which IAI leads to preterm birth and BPD are poorly understood, and there are no effective therapies for preterm birth and BPD. The transcription factor c-Myc regulates various biological processes like cell growth, apoptosis, and inflammation. We hypothesized that c-Myc modulates inflammation at the maternal-fetal interface, and neonatal lung remodeling. The objectives of our study were 1) to determine the kinetics of c-Myc in the placenta, fetal membranes and neonatal lungs exposed to IAI, and 2) to determine the role of c-Myc in modulating inflammation at the maternal-fetal interface, and neonatal lung remodeling induced by IAI. Methods: Pregnant Sprague-Dawley rats were randomized into three groups: 1) Intra-amniotic saline injections only (control), 2) Intra-amniotic lipopolysaccharide (LPS) injections only, and 3) Intra-amniotic LPS injections with c-Myc inhibitor 10058-F4. c-Myc expression, markers of inflammation, angiogenesis, immunohistochemistry, and transcriptomic analyses were performed on placenta and fetal membranes, and neonatal lungs to determine kinetics of c-Myc expression in response to IAI, and effects of prenatal systemic c-Myc inhibition on lung remodeling at postnatal day 14. Results: c-Myc was upregulated in the placenta, fetal membranes, and neonatal lungs exposed to IAI. IAI caused neutrophil infiltration and neutrophil extracellular trap (NET) formation in the placenta and fetal membranes, and neonatal lung remodeling with pulmonary hypertension consistent with a BPD phenotype. Prenatal inhibition of c-Myc with 10058-F4 in IAI decreased neutrophil infiltration and NET formation, and improved neonatal lung remodeling induced by LPS, with improved alveolarization, increased angiogenesis, and decreased pulmonary vascular remodeling. Discussion: In a rat model of IAI, c-Myc regulates neutrophil recruitment and NET formation in the placenta and fetal membranes. c-Myc also participates in neonatal lung remodeling induced by IAI. Further studies are needed to investigate c-Myc as a potential therapeutic target for IAI and IAI-associated BPD. [ABSTRACT FROM AUTHOR] more...

Mechanical ventilation from birth with normal tidal volumes (VT) causes lung injury and systemic responses in preterm sheep. The addition of budesonide to surfactant therapy decreases these injury markers. Budesonide and surfactant will decrease the injury from injurious VT ventilation in preterm sheep. Lambs at 126 ± 1 day gestational age were ventilated from birth with either: 1) Normal VT [surfactant 200 mg/kg before ventilation, positive end expiratory pressure (PEEP) 5 cmH2O, VT 8 mL/kg] or 2) Injury VT (high pressure, 100% oxygen, no PEEP) for 15 min, then further randomized to surfactant + saline or surfactant + 0.25 mg/kg budesonide with Normal VT for 6 h. Lung function and lung, liver, and brain tissues were evaluated for indicators of injury. Injury VT + saline caused significant injury and systemic responses, and Injury VT + budesonide improved lung physiology. Budesonide decreased lung inflammation and decreased pro-inflammatory cytokine mRNA in the lung, liver, and brain to levels similar to Normal VT + saline. Budesonide was present in plasma within 15 min of treatment in both ventilation groups, and less than 5% of the budesonide remained in the lung at 6 h. mRNA sequencing of liver and periventricular white matter demonstrated multiple pathways altered by both Injury VT and budesonide and the combination exposure. In lambs receiving Injury VT, the addition of budesonide to surfactant improved lung physiology and decreased pro-inflammatory cytokine responses in the lung, liver, and brain to levels similar to lambs receiving Normal VT. [ABSTRACT FROM AUTHOR] more...

Cleft lip and palate (CLP) is the most common congenital defect of the face. Many animal models have been utilized to study embryogenesis and pathogenesis of CLP, including the development of secondary anomalies and consequent deformities. However, the ideal gestational age for surgical creation of lip or palate defects in rat models has never been determined. The aim of the present study is to improve the experimental model utilizing rat fetuses, defining the most appropriate timing for creation of the lip defect model. The study was composed of three groups of fetuses undergoing surgical creation of a lip defect at the left side of the superior lip at 17.5, 18.5, and 19.5 days of gestation. Fetuses were harvested at 21.5 days of gestation (term = 22 days) and underwent macroscopic and microscopic analyses. We found that the most appropriate moment for lip defect creation was at 19.5 days, given the presence of lip depression at the site of the defect and asymmetry and retraction associated with interruption of the lip and complete reepithelialization of the borders of the defect. [ABSTRACT FROM AUTHOR] more...

Objective. The aim of this study is to report the use of a female condom as a non-surgical silon pouch in the early management of newborns with gastroschisis with large visceroabdominal disproportion. Methods. Pre-washed, sterile female condoms without spermicide were used as an early approach to treat gastroschisis in 20 newborns with large defects and in whom staged correction was anticipated. The condom was placed in the neonatal intensive care unit using sterile technique, with no anesthesia, and it was removed only at the time of the surgical procedure for gastroschisis correction. Results. There were no complications associated with the use of a female condom as a temporary silo for gastroschisis. It protected the exposed organs and also allowed a careful evaluation of the bowel and a better pre-operative planning without the need for emergency procedures. Conclusion. The use of a female condom as a silon pouch is a low-cost and simple alternative in the initial management of newborns with gastroschisis in whom primary correction is considered non-feasible. [ABSTRACT FROM AUTHOR] more...

Copyright of Arquivos de Neuro-Psiquiatria is the property of Thieme Medical Publishing Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...

Direct lung administration of budesonide in combination with surfactant reduces the incidence of bronchopulmonary dysplasia. Although the therapy is currently undergoing clinical development, the lung distribution of budesonide throughout the premature neonatal lung has not yet been investigated. Here, we applied mass spectrometry imaging (MSI) to investigate the surfactant-assisted distal lung distribution of budesonide. Unlabeled budesonide was either delivered using saline as a vehicle (n = 5) or in combination with a standard dose of the porcine surfactant Poractant alfa (n = 5). These lambs were ventilated for one minute, and then the lungs were extracted for MSI analysis. Another group of lambs (n = 5) received the combination of budesonide and Poractant alfa, followed by two hours of mechanical ventilation. MSI enabled the label-free detection and visualization of both budesonide and the essential constituent of Poractant alfa, the porcine surfactant protein C (SP-C). 2D ion intensity images revealed a non-uniform distribution of budesonide with saline, which appeared clustered in clumps. In contrast, the combination therapy showed a more homogeneous distribution of budesonide throughout the sample, with more budesonide distributed towards the lung periphery. We found similar distribution patterns for the SP-C and budesonide in consecutive lung tissue sections, indicating that budesonide was transported across the lungs associated with the exogenous surfactant. After two hours of mechanical ventilation, the budesonide intensity signal in the 2D ion intensity maps dropped dramatically, suggesting a rapid lung clearance and highlighting the relevance of achieving a uniform surfactant-assisted lung distribution of budesonide early after delivery to maximize the anti-inflammatory and maturational effects throughout the lung. [ABSTRACT FROM AUTHOR] more...

Supplemental oxygen (O2) therapy in preterm infants impairs lung development, but the impact of O2 on long‐term systemic vascular structure and function has not been well‐explored. The present study tested the hypothesis that neonatal O2 therapy induces long‐term structural and functional alterations in the systemic vasculature, resulting in vascular stiffness observed in children and young adults born preterm. Newborn Sprague‐Dawley rats were exposed to normoxia (21% O2) or hyperoxia (85% O2) for 1 and 3 weeks. A subgroup exposed to 3 weeks hyperoxia was recovered in normoxia for an additional 3 weeks. Aortic stiffness was assessed by pulse wave velocity (PWV) using Doppler ultrasound and pressure myography. Aorta remodeling was assessed by collagen deposition and expression. Left ventricular (LV) function was assessed by echocardiography. We found that neonatal hyperoxia exposure increased vascular stiffness at 3 weeks, which persisted after normoxic recovery at 6 weeks of age. These findings were accompanied by increased PWV, aortic remodeling, and altered LV function as evidenced by decreased ejection fraction, cardiac output, and stroke volume. Importantly, these functional changes were associated with increased collagen deposition in the aorta. Together, these findings demonstrate that neonatal hyperoxia induces early and sustained biomechanical alterations in the systemic vasculature and impairs LV function. Early identification of preterm infants who are at risk of developing systemic vascular dysfunction will be crucial in developing targeted prevention strategies that may improve the long‐term cardiovascular outcomes in this vulnerable population. [ABSTRACT FROM AUTHOR] more...

Background: Neonatal hyperoxia exposure is associated with brain injury and poor neurodevelopment outcomes in preterm infants. Our previous studies in neonatal rodent models have shown that hyperoxia stimulates the brain's inflammasome pathway, leading to the activation of gasdermin D (GSDMD), a key executor of pyroptotic inflammatory cell death. Moreover, we found inhibition of GSDMD activation attenuates hyperoxia-induced brain injury in neonatal mice. We hypothesized that GSDMD plays a pathogenic role in hyperoxia-induced neonatal brain injury and that GSDMD gene knockout (KO) will alleviate hyperoxia-induced brain injury. Methods: Newborn GSDMD knockout mice and their wildtype (WT) littermates were randomized within 24 h after birth to be exposed to room air or hyperoxia (85% O2) from postnatal day 1 to 14. Hippocampal brain inflammatory injury was assessed in brain sections by immunohistology for allograft inflammatory factor 1 (AIF1), a marker of microglial activation. Cell proliferation was evaluated by Ki-67 staining, and cell death was determined by TUNEL assay. RNA sequencing of the hippocampus was performed to identify the transcriptional effects of hyperoxia and GSDMD-KO, and qRT-PCR was performed to confirm some of the significantly regulated genes. Results: Hyperoxia-exposed WT mice had increased microglia consistent with activation, which was associated with decreased cell proliferation and increased cell death in the hippocampal area. Conversely, hyperoxia-exposed GSDMD-KO mice exhibited considerable resistance to hyperoxia as O2 exposure failed to increase either AIF1+ or TUNEL+ cell numbers, nor decrease cell proliferation. Hyperoxia exposure differentially regulated 258 genes in WT and only 16 in GSDMD-KO mice compared to room air- exposed WT and GSDMD-KO, respectively. Gene set enrichment analysis showed that in the WT brain, hyperoxia differentially regulated genes associated with neuronal and vascular development and differentiation, axonogenesis, glial cell differentiation, and core development pathways hypoxia-induced factor 1, and neuronal growth factor pathways. These changes were prevented by GSDMD-KO. Conclusion: GSDMD-KO alleviates hyperoxia-induced inflammatory injury, cell survival and death, and alterations of transcriptional gene expression of pathways involved in neuronal growth, development, and differentiation in the hippocampus of neonatal mice. This suggests that GSDMD plays a pathogenic role in preterm brain injury, and targeting GSDMD may be beneficial in preventing and treating brain injury and poor neurodevelopmental outcomes in preterm infants. more...

Vertical transmission of SARS-CoV-2 from mother to fetus is widely accepted. Whereas most infected neonates present with mild symptoms or are asymptomatic, respiratory distress syndrome (RDS) and abnormal lung images are significantly more frequent in COVID-19 positive neonates than in non-infected newborns. Fatality is rare and discordant meta-analyses of case reports and series relating perinatal maternal COVID-19 status to neonatal disease severity complicate their extrapolation as prognostic indicators. A larger database of detailed case reports from more extreme cases will be required to establish therapeutic guidelines and allow informed decision making. Here we report an unusual case of a 28 weeks' gestation infant with perinatally acquired SARS-CoV-2, who developed severe protracted respiratory failure. Despite intensive care from birth with first line anti-viral and anti-inflammatory therapy, respiratory failure persisted, and death ensued at 5 months. Lung histopathology showed severe diffuse bronchopneumonia, and heart and lung immunohistochemistry confirmed macrophage infiltration, platelet activation and neutrophil extracellular trap formation consistent with late multisystem inflammation. To our knowledge, this is the first report of SARS CoV-2 pulmonary hyperinflammation in a preterm newborn with fatal outcome., Competing Interests: KW were employed by Integene International, LLC. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Aguilar-Caballero, Capcha, Caballero, Young, Duara, Borchetta, Gonzalez, Saad, Webster, Shehadeh, Bandstra and Schmidt.) more...

Antenatal steroid (ANS) therapy is the standard care for women at imminent risk of preterm labor. Despite extensive and long-standing use, 40%-50% of babies exposed antenatally to steroids do not derive benefit; remaining undelivered 7 days or more after ANS treatment is associated with a lack of treatment benefit and increased risk of harm. We used a pregnant sheep model to evaluate the impact of continuous versus pulsed ANS treatments on fetal lung maturation at an extended, 8-day treatment to delivery interval. Continuous low-dose ANS treatments for more than 72 h in duration improved fetal lung maturation at 8 days after treatment initiation. If fetal ANS exposure was interrupted, the beneficial ANS effect was lost. Truncated treatments, including that simulating the current clinical treatment regimen, did not improve lung function. Variable fetal lung maturation was correlated to the amount of saturated phosphatidylcholine present in the lung fluid. These data demonstrate that 1 ) the durability of ANS therapy may be enhanced by employing an extended, low-dose treatment regimen by reducing total dose and 2 ) interrupting the continuity of fetal exposure by allowing it to fall below a minimal threshold was associated with comparably poor functional maturation of the preterm ovine lung. more...

Background: Patients with congenital diaphragmatic hernia (CDH) have a short postnatal period of ventilatory stability called the honeymoon period, after which changes in pulmonary vascular reactivity result in pulmonary hypertension. However, the mechanisms involved are still unknown. The aim of this study was to evaluate mechanical ventilation's effect in the honeymoon period on VEGF, VEGFR-1/2 and eNOS expression on experimental CDH in rats. Materials and Methods: Neonates whose mothers were not exposed to nitrofen formed the control groups (C) and neonates with left-sided defects formed the CDH groups (CDH). Both were subdivided into non-ventilated and ventilated for 30, 60, and 90 min ( n = 7 each). The left lungs ( n = 4) were evaluated by immunohistochemistry of the pulmonary vasculature (media wall thickness), VEGF, VEGFR-1/2 and eNOS. Western blotting ( n = 3) was performed to quantify the expression of VEGF, VEGFR-1/2 and eNOS. Results: CDH had lower biometric parameters than C. Regarding the pulmonary vasculature, C showed a reduction in media wall thickness with ventilation, while CDH presented reduction with 30 min and an increase with the progression of the ventilatory time (honeymoon period). CDH and C groups showed different patterns of VEGF, VEGFR-1/2 and eNOS expressions. The receptors and eNOS findings were significant by immunohistochemistry but not by western blotting, while VEGF was significant by western blotting but not by immunohistochemistry. Conclusion: VEGF, its receptors and eNOS were altered in CDH after mechanical ventilation. These results suggest that the VEGF-NO pathway plays an important role in the honeymoon period of experimental CDH., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Miura da Costa, Fabro, Becari, Figueira, Schmidt, Ruano and Sbragia.) more...

Background: Dexamethasone-phosphate (Dex-PO 4 ) and the combination betamethasone-phosphate (Beta-PO 4 ) + betamethasone-acetate (Beta-Ac) are the most used antenatal corticosteroids to promote fetal lung maturation. We compared fetal lung maturation induced by Beta-Ac+Beta-PO 4 , Dex-PO 4 , or Beta-PO 4 alone., Methods: Pregnant ewes received two intramuscular doses 24 h apart of 0.25 mg/kg/dose of Beta-Ac+Beta-PO 4 , Dex-PO4 or Beta-PO 4 ; or 2 doses of 0.125 mg/kg/dose of Beta-PO 4 at 6, 12, or 24 h intervals. Fetuses were delivered 48 h after the first dose and ventilated for 30 min. We assessed ventilatory variables, vital signs, and blood gas. After ventilation pressure-volume curves were measured and lungs were sampled for analysis., Results: All treatments improved lung compliance and ventilation efficiency. Only Beta-Ac + Beta-PO 4 required lower positive inspiratory pressure compared with control. Beta-Ac + Beta-PO 4 and Beta-PO 4 alone, but not Dex-PO 4 , increased the mRNA of surfactant proteins compared with control. Low-dose Beta-PO 4 did not increase mRNA of surfactant proteins. There were no differences among Beta-PO 4 treatment intervals., Conclusion: Beta-Ac + Beta-PO 4 given as two doses 24 h apart was more effective in promoting fetal lung maturation than Dex-PO 4 or Beta-PO 4 alone, consistent with a prolonged exposure provided by the Beta-Ac + Beta-PO 4 . These results support the clinical use of combined Beta-Ac + Beta-PO 4 preparations over phosphate corticosteroids alone for fetal lung maturation. more...

Cleft lip and palate (CLP) is the most common congenital defect of the face. Many animal models have been utilized to study embryogenesis and pathogenesis of CLP, including the development of secondary anomalies and consequent deformities. However, the ideal gestational age for surgical creation of lip or palate defects in rat models has never been determined. The aim of the present study is to improve the experimental model utilizing rat fetuses, defining the most appropriate timing for creation of the lip defect model. The study was composed of three groups of fetuses undergoing surgical creation of a lip defect at the left side of the superior lip at 17.5, 18.5, and 19.5 days of gestation. Fetuses were harvested at 21.5 days of gestation (term  =  22 days) and underwent macroscopic and microscopic analyses. We found that the most appropriate moment for lip defect creation was at 19.5 days, given the presence of lip depression at the site of the defect and asymmetry and retraction associated with interruption of the lip and complete reepithelialization of the borders of the defect. more...

Background: Neonates with severe neurological impairment are often unable to swallow, necessitating gastrostomy for feeding. Because of the risk of developing severe reflux, this procedure is often associated with fundoplication., Objective: To assess the safety and efficacy of gastrostomy and Nissen fundoplication in 22 neonates with swallowing difficulties due to serious neurological impairment., Method: All children underwent an initial period of nasogastric feeding and after informed consent underwent gastrostomy and Nissen fundoplication., Results: There were no significant intraoperative complications. There were two cases of postoperative periostomy leakage. Of the 22 neonates 16 were alive four months after surgery. Six neonates died of complications due to underlying disease., Conclusion: We concluded that gastrostomy and Nissen fundoplication are safe procedures and help parents give a better care to these children. more...