Direct thrombin inhibitors fail to reverse the negative effects of heparin on lung growth and function after murine left pneumonectomy.

Neonates with congenital diaphragmatic hernia (CDH) frequently require cardiopulmonary bypass and systemic anticoagulation. We previously demonstrated that even subtherapeutic heparin impairs lung growth and function in a murine model of compensatory lung growth (CLG). The direct thrombin inhibitors (DTIs) bivalirudin and argatroban preserved growth in this model. Although DTIs are increasingly used for systemic anticoagulation clinically, patients with CDH may still receive heparin. In this experiment, lung endothelial cell proliferation was assessed following treatment with heparin-alone or mixed with increasing concentrations of bivalirudin or argatroban. The effects of subtherapeutic heparin with or without DTIs in the CLG model were also investigated. C57BL/6J mice underwent left pneumonectomy and subcutaneous implantation of osmotic pumps. Pumps were preloaded with normal saline, bivalirudin, or argatroban; treated animals received daily intraperitoneal low-dose heparin. In vitro, heparin-alone decreased endothelial cell proliferation and increased apoptosis. The effect of heparin on proliferation, but not apoptosis, was reversed by the addition of bivalirudin and argatroban. In vivo, low-dose heparin decreased lung volume compared with saline-treated controls. All three groups that received heparin demonstrated decreased lung function on pulmonary function testing and impaired exercise performance on treadmill tolerance testing. These findings correlated with decreases in alveolarization, vascularization, angiogenic signaling, and gene expression in the heparin-exposed groups. Together, these data suggest that bivalirudin and argatroban fail to reverse the inhibitory effects of subtherapeutic heparin on lung growth and function. Clinical studies on the impact of low-dose heparin with DTIs on CDH outcomes are warranted.NEW & NOTEWORTHY Infants with pulmonary hypoplasia frequently require cardiopulmonary bypass and systemic anticoagulation. We investigate the effects of simultaneous exposure to heparin and direct thrombin inhibitors (DTIs) on lung growth and pulmonary function in a murine model of compensatory lung growth (CGL). Our data suggest that DTIs fail to reverse the inhibitory effects of subtherapeutic heparin on lung growth and function. Clinical studies on the impact of heparin with DTIs on clinical outcomes are thus warranted.

The ten-year evaluation of clinical characteristics in congenital lung anomaly in pediatrics; a retrospective study in North of Iran.

INTRODUCTION: Congenital lung anomalies (CLA) are a group of anomalies, including congenital cystic adenomatoid malformation (CCAM), bronchopulmonary sequestrations (BPS), congenital lobar emphysema (CLE), and bronchogenic cysts (BC). The prevalence of these rare anomalies has risen in recent years, according to various population-based studies due to advances in fetal ultrasound technology. METHOD: This retrospective study examines the diagnosis of CLA, and was conducted on 72 patients between March 2014 and March 2024 at Taleghani Pediatric Hospital in Gorgan, Iran. RESULT: The average age was 18.8 ± 30.3 months, with the majority being boys (62.5%). Most participants had CCAM (41.7%), followed by CLE (18.1%), BPS (16.7%), pulmonary hypoplasia (9.7%), BC (8.3%), and hybrid lesion (5.6%). The majority of patients were Fars (62.5%), and the average hospitalization days was 9.4 ± 4.5 days. Cardiac anomalies were observed in 19.4% of the patients. 62 patients (86.1%) exhibited respiratory symptoms, and prenatal screening during pregnancy led to the diagnosis in 51 patients (70.8%). Most patients had left lung anomalies (43; 59.7%), and the majority (90.3%) survived. There is a statistically significant relation between needed for surgical treatment and patients' type of pulmonary lesions (p-value: 0.02). In addition, there was a significant relation between the Fars ethnicity and the presence of cardiac anomalies (p-value: 0.04). CONCLUSION: Some CLAs remain undiagnosed or untreated due to the rare nature of congenital lung anomalies. Nevertheless, improvements in ultrasound and other imaging methods will make diagnosing and managing these anomalies during the prenatal period more prevalent, resulting in enhanced understanding.

The RNA-binding protein quaking is upregulated in nitrofen-induced congenital diaphragmatic hernia lungs at the end of gestation.

BACKGROUND: The RNA-binding protein Quaking (QKI) increases during epithelial-to-mesenchymal transition and its expression is controlled by microRNA-200 family members. Here, we aimed to describe the expression of QKI in the developing lungs of control and nitrofen-induced congenital diaphragmatic hernia lungs (CDH). METHODS: To investigate the expression of QKI, we dissected lungs from control and nitrofen-induced CDH rats on embryonic day 15, 18, 21 (E15, E18, E21). We performed immunofluorescence (IF) and quantitative reverse transcription PCR (RT-qPCR) for QKI expression. Additionally, we assessed Interleukin-6 (IL-6) abundance using IF. RESULTS: On E21, IF showed that the abundance of all three QKI isoforms and IL-6 protein was higher in CDH lungs compared to control lungs (QKI5: p = 0.023, QKI6: p = 0.006, QKI7: p = 0.014, IL-6: p = 0.045, respectively). Furthermore, RT-qPCR data showed increased expression of QKI5, QKI6, and QKI7 mRNA in E21 nitrofen lungs by 1.63 fold (p = 0.001), 1.63 fold (p = 0.010), and 1.48 fold (p = 0.018), respectively. CONCLUSIONS: Our data show an increase in the abundance and expression of QKI at the end of gestation in nitrofen-induced CDH lungs. Therefore, a disruption in the regulation of QKI during the late stage of pregnancy could be associated with the pathogenesis of abnormal lung development in CDH.

Abnormal Shape and Size of the Cardiac Ventricles Are Associated with a Higher Risk of Neonatal Death in Fetuses with Isolated Left Congenital Diaphragmatic Hernia.

INTRODUCTION: The objective of this study was to evaluate the association between fetal cardiac deformation analysis (CDA) and cardiac function with severe adverse perinatal outcomes in fetuses with isolated left congenital diaphragmatic hernia (CDH). METHODS: CDA in each ventricle (contractility, size, and shape), evaluated by speckle tracking and novel FetalHQ software, and markers of cardiac function (E/A ratios, pulmonary and aortic peak systolic velocities, and sigmoid annular valve diameters), were evaluated in fetuses with isolated left CDH. Two evaluations were performed: at referral (CDA and function) and within 3 weeks of delivery (CDA). Severe adverse neonatal outcomes were considered neonatal death (ND) or survival with CDH-associated pulmonary hypertension (CDH-PH). Differences and associations between CDA, cardiac function, and severe adverse outcomes were estimated. RESULTS: Fifty fetuses were included, and seventeen (34%) had severe adverse neonatal outcomes (11 ND and 6 survivors with CDH-PH). At first evaluation, the prevalence of a small left ventricle was 34% (17/50) with a higher prevalence among neonates presenting severe adverse outcomes (58.8 [10/17] vs. 21.2% [7/33]; p = 0.01; OR, 5.03 [1.4-19.1; p = 0.01]) and among those presenting with neonatal mortality (8/11 [72.7] vs. 9/39 [23.0%]; p = 0.03; OR, 8.9 [1.9-40.7; p = 0.005]). No differences in cardiac function or strain were noted between fetuses with or without severe adverse outcomes. Within 3 weeks of delivery, the prevalence of small left ventricle was higher (19/34; 55.8%) with a more globular shape (reduced transverse/longitudinal ratio). A globular right ventricle was significantly associated with ND or survival with CDH-PH (OR, 14.2 [1.5-138.3]; p = 0.02). CONCLUSION: Fetuses with isolated CDH at risk of perinatal death or survival with CDH-PH had a higher prevalence of a small left ventricle and abnormal shape of the right ventricle.

Connecting clinical, environmental, and genetic factors point to an essential role for vitamin A signaling in the pathogenesis of congenital diaphragmatic hernia.

Congenital diaphragmatic hernia (CDH) is a developmental disorder that results in incomplete diaphragm formation, pulmonary hypoplasia, and pulmonary hypertension. Although a variety of genes have been linked to its etiology, CDH is not a monogenetic disease, and the cause of the condition is still unclear in the vast majority of clinical cases. By comparing human clinical data and experimental rodent data from the literature, we present clear support demonstrating the importance of vitamin A (vitA) during the early window of pregnancy when the diaphragm and lung are forming. Alteration of vitA signaling via dietary and genetic perturbations can create diaphragmatic defects. Unfortunately, vitA deficiency is chronic among people of child-bearing age, and this early window of diaphragm development occurs before many might be aware of pregnancy. Furthermore, there is an increased demand for vitA during this critical period, which exacerbates the likelihood of deficiency. It would be beneficial for the field to further investigate the connections between maternal vitA and CDH incidence, with the goal of determining vitA status as a CDH risk factor. Regular clinical monitoring of vitA levels in child-bearing years is a tractable method by which CDH outcomes could be prevented or improved.

Mechanics of Lung Development.

We summarize how skeletal muscle and lung developmental biology fields have been bridged to benefit from mouse genetic engineering technologies and to explore the role of fetal breathing-like movements (FBMs) in lung development, by using skeletal muscle-specific mutant mice. It has been known for a long time that FBMs are essential for the lung to develop properly. However, the cellular and molecular mechanisms transducing the mechanical forces of muscular activity into specific genetic programs that propel lung morphogenesis (development of the shape, form and size of the lung, its airways, and gas exchange surface) as well as its differentiation (acquisition of specialized cell structural and functional features from their progenitor cells) are only starting to be revealed. This chapter is a brief synopsis of the cumulative findings from that ongoing quest. An update on and the rationale for our recent International Mouse Phenotyping Consortium (IMPC) search is also provided.

Survival in very preterm infants with congenital diaphragmatic hernia and association with prenatal imaging markers: A retrospective cohort study.

OBJECTIVES: To describe the outcomes of preterm born infants with congenital diaphragmatic hernia (CDH; ≤32.0 weeks of gestation) and the associations between prenatal imaging markers and survival. DESIGN: Retrospective cohort study. SETTING: Multicentre study in large referral centres. POPULATION: Infants with an isolated unilateral CDH, live born at 32.0 weeks or less of gestation, between January 2009 and January 2020. METHODS: Neonatal outcomes were evaluated for infants that were expectantly managed during pregnancy and infants that underwent fetoscopic endoluminal tracheal occlusion (FETO) therapy, separately. We evaluated the association between prenatal imaging markers and survival to discharge. Prenatal imaging markers included observed to expected lung-to-head ratio (o/e LHR), side of the defect, liver position, stomach position grade, and observed to expected total fetal lung volume (o/e TFLV). MAIN OUTCOME MEASURE: Survival to discharge. RESULTS: We included 53 infants born at 30+4 (interquartile range 29+1 -31+2 ) weeks. Survival in fetuses expectantly managed during pregnancy was 48% (13/27) in left-sided CDH and 33% (2/6) in right-sided CDH. Survival in fetuses that underwent FETO therapy was 50% (6/12) in left-sided CDH and 25% (2/8) in right-sided CDH. The o/e LHR at baseline was positively associated with survival in cases expectantly managed during pregnancy (odds ratio [OR] 1.20, 95% CI 1.07-1.42, p < 0.01), but not in cases that received FETO therapy (OR 1.01, 95% CI 0.88-1.15, p = 0.87). Stomach position grade (p = 0.03) and o/e TFLV were associated with survival (p = 0.02); liver position was not (p = 0.13). CONCLUSIONS: In infants with CDH born at or before 32 weeks of gestation, prenatal imaging markers of disease severity were associated with postnatal survival.

Potter Deformation Sequence Caused by 17q12 Deletion: A Lethal Constellation.

17q12 deletion syndrome causes developmental abnormalities of the kidneys, pancreas, genital tract, and neurodevelopment, and it has a wide range of phenotypes ranging from fetal demise to normal adulthood with minimal renal impairment. Here we describe a rare case of 17q12 deletion diagnosed prenatally, complicated by anhydramnios and Potter sequence. The baby was born but necessitated life-saving interventions due to pulmonary and renal insufficiency and ultimately succumbed to multi-organ failure. We present full autopsy results describing findings linked to 17q12 deletion, including severe bilateral multicystic renal dysplasia, pancreatic hypoplasia, and cysts adjacent to the Fallopian tubes. We also describe pulmonary hypoplasia and Potter facies as consequences of anhydramnios. We correlate these findings to our current understanding of molecular signals altered by 17q12 deletion, notably affecting HNF1B and LHX1 genes, which are known to mediate renal and genitourinary tract development.

Inhaled nitric oxide in preterm neonates with preterm prelabour rupture of membranes, a systematic review.

AIM: To perform a systematic literature review to determine the effect of inhaled nitric oxide (iNO) on oxygenation, mortality and morbidity in preterm neonates with preterm prelabour rupture of membranes (PPROM) and early hypoxaemic respiratory failure (HRF). METHODS: MEDLINE, Embase, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, Web of Science, Zetoc and ProQuest were searched. Studies including neonates <34 weeks' gestation with PPROM, oligohydramnios or pulmonary hypoplasia and HRF in the first 28 days of life treated with iNO were included. Studies were critically appraised and assessed for potential risk of bias using standardised checklists. RESULTS: Six hundred and two records remained after duplicates were removed. Seven studies were included in the critical appraisal process. Quality of available evidence was very low to low. Six studies described an improvement in oxygenation after commencement of iNO. One hundred and three of 284 (36%) neonates exposed to iNO died. Seventy-seven of 92 (84%) neonates that had an echocardiogram performed before commencement of iNO had pulmonary hypertension (PH) present. CONCLUSION: iNO may improve oxygenation when standard care fails. Improvement in oxygenation is likely associated with increase in survival. Survival may lead to an increase in morbidity. Efficacy of iNO in this cohort is likely secondary to relatively high prevalence of PH.

Anti-inflammatory effects of antenatal administration of stem cell derived extracellular vesicles in the brain of rat fetuses with congenital diaphragmatic hernia.

PURPOSE: Congenital diaphragmatic hernia (CDH) survivors may experience neurodevelopmental impairment, whose etiology remains elusive. Preclinical evidence indicates that amniotic fluid stem cell extracellular vesicle (AFSC-EV) administration promotes lung development but their effects on other organs are unknown. Herein, we investigated the brain of rat fetuses with CDH for signs of inflammation and response to AFSC-EVs. METHODS: CDH was induced by maternal nitrofen administration at E9.5. At E18.5, fetuses were injected intra-amniotically with saline or AFSC-EVs (isolated by ultracentrifugation, characterized as per MISEV guidelines). Fetuses from vehicle-gavaged dams served as controls. Groups were compared for: lung hypoplasia, TNFa and IL-1B brain expression, and activated microglia (Iba1) density in the subgranular zone (SGZ). RESULTS: CDH lungs had fewer airspaces compared to controls, whereas AFSC-EV-treated lungs had rescued branching morphogenesis. Fluorescently labeled AFSC-EVs injected intra-amniotically into CDH fetuses had fluorescent signal in the brain. Compared to controls, the brain of CDH fetuses had higher TNFa and IL-1B levels, and increased activated microglia density. Conversely, the brain of AFSC-EV treated fetuses had inflammatory marker expression levels and microglia density similar to controls. CONCLUSION: This study shows that the brain of rat fetuses with CDH has signs of inflammation that are abated by the intra-amniotic administration of AFSC-EVs.

Characterization of the congenital diaphragmatic hernia model in C57BL/6J fetal mice: a step toward lineage tracing experiments.

PURPOSE: Lineage tracing is key to study the fate of individual cells and their progeny especially in developmental biology. To conduct these studies, we aimed to establish a reproducible model of CDH in the most commonly used genetic background strain that is C57BL/6J mice. METHODS: CDH was induced in C57BL/6J dams by maternal administration of nitrofen + bisdiamine at E8.5. Fetuses from olive oil-gavaged mothers served as controls. Lungs from CDH and control fetuses were compared for (1) growth via radial airspace count (RAC), mean linear intercept (MLI) and gene expression for Fgf10, Nrp1, and Ctnnb1; (2) maturation (Pdpn, Spc, Ager, Abca3, Eln, Acta2, Pdgfra) via gene and protein expression; (3) vascularization via gene and protein expression (CD31, Vegfa, Vegfr1/2, Epas1, Enos). STATISTICS: unpaired t-test or Mann-Whitney test. RESULTS: Nitrofen + bisdiamine administration resulted in 36% left-sided CDH (31% mortality). CDH fetuses had hypoplastic lungs and impaired growth (lower RAC, higher MLI, lower Fgf10, Nrp1, Ctnnb1), maturation (decreased Pdpn, Ager, Eln gene expression), and vascularization (decreased Cd31, Vegfr1/2; Epas1 and Enos). Lower protein expression was confirmed for PDPN, ELN and CD31. CONCLUSION: Modeling CDH in C57BL/6J mouse fetuses is effective in reproducing the classical CDH hallmarks. This model will be critical for lineage tracing experiments.

Deficiency in pigment epithelium-derived factor accelerates pulmonary growth and development in a compensatory lung growth model.

Children with hypoplastic lung disease associated with congenital diaphragmatic hernia (CDH) continue to suffer significant morbidity and mortality secondary to progressive pulmonary disease. Recently published work from our lab demonstrated the potential of Roxadustat (FG-4592), a prolyl hydroxylase inhibitor, as a treatment for CDH-associated pulmonary hypoplasia. Treatment with Roxadustat led to significantly accelerated compensatory lung growth (CLG) through downregulation of pigment epithelium-derived factor (PEDF), an anti-angiogenic factor, rather than upregulation of vascular endothelial growth factor (VEGF). PEDF and its role in pulmonary development is a largely unexplored field. In this study, we sought to further evaluate the role of PEDF in accelerating CLG. PEDF-deficient mice demonstrated significantly increased lung volume, total lung capacity, and alveolarization compared to wild type controls following left pneumonectomy without increased VEGF expression. Furthermore, Roxadustat administration in PEDF-deficient mice did not further accelerate CLG. Human microvascular endothelial lung cells (HMVEC-L) and human pulmonary alveolar epithelial cells (HPAEC) similarly demonstrated decreased PEDF expression with Roxadustat administration. Additionally, downregulation of PEDF in Roxadustat-treated HMVEC-L and HPAEC, a previously unreported finding, speaks to the potential translatability of Roxadustat from small animal studies. Taken together, these findings further suggest that PEDF downregulation is the primary mechanism by which Roxadustat accelerates CLG. More importantly, these data highlight the critical role PEDF may have in pulmonary growth and development, a previously unexplored field.

Exacerbation of mild lung disorders to lethal pulmonary hypoplasia by a noncoding hypomorphic SNV in a lung-specific enhancer in trans to the frameshifting TBX4 variant.

Variants involving TBX4 are associated with a wide variety of disorders, including pulmonary arterial hypertension, ischiocoxopodopatellar syndrome (ICPPS)/small patella syndrome (SPS), lethal lung developmental disorders (LLDDs) in neonates, heart defects, and prenatally lethal posterior amelia with pelvic and pulmonary hypoplasia syndrome. The objective of our study was to elucidate the wide variable phenotypic expressivity and incomplete penetrance in a three-generation family with a truncating variant in TBX4. In addition to exome and genome sequencing analyses, a candidate noncoding regulatory single nucleotide variant (SNV) within the lung-specific TBX4 enhancer was functionally tested using an in vitro luciferase reporter assay. A heterozygous frameshift variant c.1112dup (p.Pro372Serfs*14) in TBX4 was identified in patients with mild interstitial lung disease (1), bronchiolitis obliterans (1), recurrent pneumothorax (1), ICPPS/SPS (1), LLDD (2), and in unaffected individuals (4). In two deceased neonates with LLDD, we identified a noncoding SNV rs62069651-C located in trans to the mutated TBX4 allele that reduced the TBX4 promoter activity by 63% in the reporter assay. Our findings provide a functional evidence for the recently reported model of complex compound inheritance in which both TBX4 coding and in trans noncoding hypomorphic variants in the lung-specific enhancer of TBX4 contribute to LLDD.

The randomized Tracheal Occlusion To Accelerate Lung growth (TOTAL)-trials on fetal surgery for congenital diaphragmatic hernia: reanalysis using pooled data.

BACKGROUND: Two randomized controlled trials compared the neonatal and infant outcomes after fetoscopic endoluminal tracheal occlusion with expectant prenatal management in fetuses with severe and moderate isolated congenital diaphragmatic hernia, respectively. Fetoscopic endoluminal tracheal occlusion was carried out at 27+0 to 29+6 weeks' gestation (referred to as "early") for severe and at 30+0 to 31+6 weeks ("late") for moderate hypoplasia. The reported absolute increase in the survival to discharge was 13% (95% confidence interval, -1 to 28; P=.059) and 25% (95% confidence interval, 6-46; P=.0091) for moderate and severe hypoplasia. OBJECTIVE: Data from the 2 trials were pooled to study the heterogeneity of the treatment effect by observed over expected lung-to-head ratio and explore the effect of gestational age at balloon insertion. STUDY DESIGN: Individual participant data from the 2 trials were reanalyzed. Women were assessed between 2008 and 2020 at 14 experienced fetoscopic endoluminal tracheal occlusion centers and were randomized in a 1:1 ratio to either expectant management or fetoscopic endoluminal tracheal occlusion. All received standardized postnatal management. The combined data involved 287 patients (196 with moderate hypoplasia and 91 with severe hypoplasia). The primary endpoint was survival to discharge from the neonatal intensive care unit. The secondary endpoints were survival to 6 months of age, survival to 6 months without oxygen supplementation, and gestational age at live birth. Penalized regression was used with the following covariates: intervention (fetoscopic endoluminal tracheal occlusion vs expectant), early balloon insertion (yes vs no), observed over expected lung-to-head ratio, liver herniation (yes vs no), and trial (severe vs moderate). The interaction between intervention and the observed over expected lung-to-head ratio was evaluated to study treatment effect heterogeneity. RESULTS: For survival to discharge, the adjusted odds ratio of fetoscopic endoluminal tracheal occlusion was 1.78 (95% confidence interval, 1.05-3.01; P=.031). The additional effect of early balloon insertion was highly uncertain (adjusted odds ratio, 1.53; 95% confidence interval, 0.60-3.91; P=.370). When combining these 2 effects, the adjusted odds ratio of fetoscopic endoluminal tracheal occlusion with early balloon insertion was 2.73 (95% confidence interval, 1.15-6.49). The results for survival to 6 months and survival to 6 months without oxygen dependence were comparable. The gestational age at delivery was on average 1.7 weeks earlier (95% confidence interval, 1.1-2.3) following fetoscopic endoluminal tracheal occlusion with late insertion and 3.2 weeks earlier (95% confidence interval, 2.3-4.1) following fetoscopic endoluminal tracheal occlusion with early insertion compared with expectant management. There was no evidence that the effect of fetoscopic endoluminal tracheal occlusion depended on the observed over expected lung-to-head ratio for any of the endpoints. CONCLUSION: This analysis suggests that fetoscopic endoluminal tracheal occlusion increases survival for both moderate and severe lung hypoplasia. The difference between the results for the Tracheal Occlusion To Accelerate Lung growth trials, when considered apart, may be because of the difference in the time point of balloon insertion. However, the effect of the time point of balloon insertion could not be robustly assessed because of a small sample size and the confounding effect of disease severity. Fetoscopic endoluminal tracheal occlusion with early balloon insertion in particular strongly increases the risk for preterm delivery.

Prenatal lung volumes in congenital diaphragmatic hernia and their effect on postnatal outcomes.

Lung volume measurement on fetal MRI is a component of the imaging workup for various prenatal conditions, but its use as a prognosticator has been most heavily studied in congenital diaphragmatic hernia (CDH). Pediatric radiologists who perform and interpret fetal MRI must be familiar with the technical aspects of lung volume measurement to guarantee accurate measurement and reporting. Variability in timing and type of measurement at different fetal centers also requires pediatric radiologists to be up-to-date with the literature and aware of their center's internal data. This paper provides both a how-to guide for measuring fetal lung volumes on MRI and a comprehensive review of the CDH outcome literature to serve as a convenient reference for the pediatric radiologist.

Tenascin C is dysregulated in hypoplastic lungs of miR-200b-/- mice.

PURPOSE: We previously demonstrated that absence of miR-200b results in abnormal lung development in congenital diaphragmatic hernia due to imbalance between epithelial and mesenchymal cells. Tenascin C is a highly conserved extracellular matrix protein involved in epithelial to mesenchymal transition, tissue regeneration and lung development. Considering the involvement of Tenascin C and miR-200b and their potential interaction, we aimed to study Tenascin C during lung development in the absence of miR-200b. METHODS: We collected lungs of miR-200b-/- mice (male, 8 weeks). We performed Western blot (WB) analysis (N = 6) and immunofluorescence (N = 5) for Tenascin C and alpha smooth muscle actin and RT-qPCR for Tenascin C gene expression (N = 4). RESULTS: Using WB analysis, we observed a decreased total protein abundance of Tenascin C in miR-200b-/- lungs (miR-200b+/+: 3.8 × 107 ± 1 × 107; miR-200b-/-: 1.9 × 107 ± 5 × 106; p = 0.002). Immunofluorescence confirmed decreased total Tenascin C in miR-200b-/- lungs. Tenascin C was significantly decreased in the mesenchyme but relatively increased in the airways of mutant lungs. Total lung RNA expression of Tenascin C was higher in miR-200b-/- lungs. CONCLUSION: We report dysregulation of Tenascin C in lungs of miR-200b-/- mice. This suggests that absence of miR-200b results in abnormal Tenascin C abundance contributing to the lung hypoplasia observed in miR-200b-/- mice.

Outcomes of patients with exomphalos and associated congenital heart diseases.

INTRODUCTION: Exomphalos is an anterior abdominal wall defect resulting in herniation of contents into the umbilical cord. Severe associated chromosomal anomalies and congenital heart disease (CHD) are known to influence mortality, but it is not clear which cardiac anomalies have the greatest impact on survival. METHODS: We performed a retrospective review of the treatment and outcome of patients with exomphalos over a 30-year period (1990-2020), with a focus on those with the combination of exomphalos major and major CHD (EMCHD). RESULTS: There were 123 patients with exomphalos identified, 59 (48%) had exomphalos major (ExoMaj) (defect > 5 cm or containing liver), and 64 (52%) exomphalos minor (ExoMin). In the ExoMaj group; 17% had major CHD (10/59), M:F 28:31, 29% premature (< 37 weeks, 17/59) and 14% had low birth-weight (< 2.5 kg, 8/59). In the ExoMin group; 9% had major CHD (6/64), M:F 42:22, 18% premature and 10% had low birth-weight. The 5-year survival was 20% in the EMCHD group versus 90% in the ExoMaj with minor or no CHD [p < 0.0001]. Deaths in the EMCHD had mainly right heart anomalies and all of them required mechanical ventilation (MV) for pulmonary hypoplasia prior to cardiac intervention. In contrast, survivors did not require mechanical ventilation prior to cardiac intervention. CONCLUSION: EMCHD is associated with high mortality. The most significant finding was high mortality in those with right heart anomalies in combination with pulmonary hypoplasia, especially if pre-intervention mechanical ventilation is required.

The effect of tracheal occlusion in congenital diaphragmatic hernia in the nitrofen rat lung explant model.

PURPOSE: Here, we establish a tracheal occlusion (TO) model with rat lung explants in nitrofen-induced pulmonary hypoplasia in the congenital diaphragmatic hernia (CDH). METHODS: We extracted lungs from rats on an embryonic day 18. We mimicked TO in the lung explants by tying the trachea. We assessed lung weight, morphometry, and abundance of Ki-67, Active caspase-3, and Prosurfactant Protein C (proSP-C) with immunofluorescence. RESULTS: Lung weight was higher in TO + than TO - on day 1. Abundance of Ki-67 was higher in TO + than TO - (0.15 vs. 0.32, p = 0.009 for day 1, 0.07 vs. 0.17, p = 0.004 for day 2, 0.07 vs. 0.12, p = 0.044 for day 3), and Active caspase-3 was higher in TO + than TO - on day 2 and day 3 (0.04 vs. 0.03 p = 0.669 for day 1, 0.03 vs. 0.13 p < 0.001 for day 2, 0.04 vs. 0.17 p = 0.008 for day3). However, proSP-C protein abundance was lower in TO + than TO - (67.9 vs. 59.1 p = 0.033 for day 1, 73.5 vs. 51.6 p = 0.038 for day 2, 83.1 vs. 56.4 p = 0.009 for day 3). CONCLUSIONS: The TO model in lung explants mimics the outcomes of current surgical models of TO and further studies can reveal the cellular and molecular effects of TO in CDH lungs.

Yes-associated protein is dysregulated during nitrofen-induced hypoplastic lung development due to congenital diaphragmatic hernia.

BACKGROUND: Congenital diaphragmatic hernia (CDH) is a birth defect associated with abnormal lung development. Yes-associated protein (YAP) is a core kinase of the Hippo pathway, which controls organ size during development. The absence of YAP protein during lung development results in hypoplastic lungs comparable to the lung phenotype in CDH (Mahoney, Dev Cell 30(2):137-150, 2014). We aimed to describe the expression of YAP during normal and nitrofen-induced abnormal lung development. METHODS: Intra-gastric administration of dams with 100 mg of nitrofen was used to induce CDH and abnormal lung development in the embryos. Immunofluorescence was performed to visualize the localization of YAP and p-YAP during lung development (E15, E18, E21). Western Blotting was used to determine the abundance of YAP and p-YAP in E21 control and nitrofen-induced hypoplastic CDH lungs. RESULTS: Immunofluorescence demonstrated cytoplasmic localization of YAP protein in airway epithelial and mesenchymal cells of nitrofen-induced hypoplastic lungs compared to nuclear localization in control lungs. Western Blotting showed a decrease (p = 0.0188) in abundance of YAP (active form) and increase in p-YAP (inactive form) in hypoplastic lungs compared to control lungs. CONCLUSION: Our results demonstrate that YAP protein is mostly phosphorylated, inactive, and expressed in the cytoplasm at the later stages of nitrofen-induced hypoplastic lung development indicating that the alteration in regulation of YAP can be associated with the pathogenesis of abnormal lung development in experimental CDH.

Amnioinfusion versus Usual Care in Women with Prelabor Rupture of Membranes in Midtrimester: A Systematic Review and Meta-Analysis of Short- and Long-Term Outcomes.

INTRODUCTION: Midtrimester prelabor rupture of membranes (PROM) between 16 and 24 weeks of gestational age is a major obstetric complication with high rates of perinatal morbidity and mortality. Amnioinfusion has been proposed in women with midtrimester PROM to target oligohydramnios and subsequently enhance pulmonary development and perinatal outcomes. MATERIAL AND METHODS: The purpose of this study was to perform a systematic review and meta-analysis including all randomized clinical trials investigating amnioinfusion versus no intervention in women with PROM between 16+0 and 24+0 weeks of gestational age. Databases Central, Embase, Medline, ClinicalTrials.gov and references of identified articles were searched from inception of database to December 2021. The primary outcome was perinatal mortality. Secondary outcomes included neonatal, maternal, and long-term developmental outcomes as defined in the core outcome set for preterm birth studies. Summary measures were reported as pooled relative risk (RR) or mean difference with corresponding 95% confidence interval (CI). RESULTS: Two studies (112 patients, 56 in the amnioinfusion group and 56 in the no intervention group) were included in this review. Pooled perinatal mortality was 66.1% (37/56) in the amnioinfusion group compared with 71.4% (40/56) in no intervention group (RR 0.92, 95% CI: 0.72-1.19). Other neonatal and maternal core outcomes were similar in both groups, although due to the relatively small number of events and wide CIs, there is a possibility that amnioinfusion can be associated with clinically important benefits and harms. Long-term healthy survival was seen in 35.7% (10/28) of children assessed for follow-up and treated with amnioinfusion versus 28.6% (8/28) after no intervention (RR 1.30, 95% CI: 0.47-3.60, "best case scenario"). CONCLUSIONS: Based on these findings, the benefits of amnioinfusion for midtrimester PROM <24 weeks of gestational age are unproven, and the potential harms remain undetermined.