ObjectiveTo identify the association between birth weight (BW)-for-gestational age (GA) and pulmonary hypertension (PHTN) at 36 weeks in infants with moderate-severe bronchopulmonary dysplasia (BPD).Study DesignIn this retrospective cohort study, we followed 138 premature infants (≤28wks) with moderate and severe BPD (NIH consensus definition) born at Prentice Women’s Hospital between 2005 and 2009. BW percentiles were calculated using the Fenton growth curve for premature infants. PHTN was determined using a standardized algorithm of echocardiogram review at 36 weeks. Logistic regression was used to evaluate the associations between BW percentile subgroups and PHTN, taking into account antenatal and neonatal factors that were related to PHTN.ResultsPHTN was associated with small BW-for-GA, ranging from thresholds of <10th to <25th percentile (P<0.001). These associations remained significant when comparing BW <25th percentile to the reference group (50–89th percentile); after adjustment for GA, gender, multiple gestation, race/ethnicity (OR=4.2; 95% CI=1.5, 12.1); and after further adjustment for maternal vascular disease, intrauterine infection, oligohydramnios, and relevant postnatal factors (OR=5.7; 95% CI=1.5, 21.2). Longitudinal follow-up of this cohort showed a trend towards higher morbidity and death among PHTN infants with BW <25th percentile.ConclusionBW-for-GA is an important predictor of PHTN in premature infants with moderate/severe BPD. Our findings contribute to the growing evidence supporting fetal mechanisms of later onset pulmonary vascular disease.

Introduction Bronchopulmonary dysplasia (BPD) is the most common chronic lung disease of infancy, and BPD-associated pulmonary hypertension (PH) is a serious complication that can negatively impact later childhood health. There is growing evidence that lung injury leading to BPD and PH is due to chronic fetal hypoxia-ischemia. The purpose of this study was to investigate whether placental pathologic changes of maternal vascular underperfusion (MVU) are associated with BPD, and further increased with PH. Methods We conducted a 5-year retrospective cohort study of premature infants born ≤28 weeks. BPD was defined as persistent oxygen requirement at 36 weeks corrected gestational age. PH was identified using a standardized algorithm of echocardiogram review. Archived placental slides underwent standardized masked histopathologic review. Logistic regression modeling was performed, taking into account important maternal and infant covariates. Results Among 283 births, 121 had MVU, of which 67 (55%) developed BPD, and 24 (20%) had PH. Among the common neonatal complications of extreme prematurity, BPD was the only outcome that was increased with MVU (P<0.001). After adjustment for birth weight, fetal growth restriction, preeclampsia and other factors, infants with MVU were more likely to develop BPD (adjusted odds ratio=2.6; 95% confidence interval=1.4, 4.8). Certain MVU sublesions (fibrinoid necrosis/acute atherosis and distal villous hypoplasia/small terminal villi) were increased with PH (P<0.001). Discussion Placental MVU may identify BPD infants who were exposed to intrauterine hypoxia-ischemia, which increases their risk for development of PH disease. Conclusions Our findings have important implications for providing earlier and more effective therapies for BPD.

Liver regeneration after partial hepatectomy (PH) involves several signaling mechanisms including activation of the small GTPases Ras and RhoA in response to mitogens leading to DNA synthesis and cell proliferation. Peroxisome proliferator-activated receptor-alpha (PPARalpha) regulates the expression of several key enzymes in isoprenoid synthesis, which are key events for membrane association of Ras and RhoA. Thus the role of PPARalpha in cell proliferation after PH was tested. After PH, an increase in PPARalpha DNA binding was observed in wild-type mice, correlating with an increase in the PPARalpha-regulated enzyme acyl-CoA oxidase. In addition, the PPARalpha-regulated genes farnesyl pyrophosphate synthase and 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) synthase were significantly increased in wild-type mice. However, these increases were not observed in PPARalpha knockout (PPARalpha -/-) mice. The peak in DNA synthesis observed 42 h after PH was reduced by approximately 60% in PPARalpha -/- mice, despite increases in TNF-alpha and IL-1. Also, under these conditions, membrane association of Ras was high in wild-type mice after PH but was impaired in PPARalpha -/- mice. Accordingly, Ras was significantly elevated in the cytosol in PPARalpha -/- mice. This observation correlated with lower levels of active GTP-bound Ras after PH in PPARalpha -/- mice compared with wild-type mice. Similar observations were made for RhoA. Moreover, deletion of PPARalpha blunted the activation of cyclin-dependent kinase (cdk)2/cyclin E and cdk4/cyclin D complexes. Collectively, these results support the hypothesis that PPARalpha is necessary for cell cycle progression in regenerating mouse liver via mechanisms involving prenylation of small GTPases Ras and RhoA.

The production of superoxide from NADPH oxidase by macrophages in response to endotoxin (LPS) is an important innate immune response, yet it is not clear how LPS signals the activation of NADPH oxidase. The hypothesis is that LPS-induced src kinase and PI3 kinase (PI3K) facilitates the activation of p47 phox , the regulatory subunit of NADPH oxidase. In mouse macrophage RAW264.7 cells, inhibition of src tyrosine family kinases inhibited LPS-induced activation of NADPH oxidase, phosphorylation of p47phox, activation of PI3K and phosphorylation of the TLR4. Moreover, inhibition of LPS-induced increases in intracellular calcium blunted src kinase activation, PI3K association with TLR4, as well as PI3 kinase activation. These data suggest that both src kinase and PI3 kinase are involved in LPS-induced NADPH oxidase activation. Importantly, these data suggest that LPS-induced src kinase activation is critical for PI3 kinase activation as well as TLR4 phosphorylation and is dependent upon LPS-induced increase in intracellular calcium. These signaling events fill critical gaps in our understanding of LPS-induced free radical production as well as may potentially responsible for the mechanism of innate immune tolerance or desensitization caused by steroids or ethanol.

BackgroundMedically complex patients in neonatal intensive care units (NICUs) typically require long hospitalisations and care from multiple subspecialists. Scheduled multidisciplinary discussions could improve collaboration and continuity of care and thereby improve patient outcomes. The specific aims of the project were to decrease the average length of hospitalisation by at least 1 day and improve parent satisfaction ratings on a standard questionnaire by the end of our project’s first year, and to maintain a stable (or decreased) cause-related (30-day) readmission rate.MethodsWe designed a quality improvement project to enhance collaboration and continuity of care for medically complex infants cared for in the NICU of Brenner Children’s Hospital. Weekly multidisciplinary team meetings were held to discuss the long-term plan for patients who met specific criteria. Attendees included attending neonatologists, paediatric surgeons, a physical therapist, an occupational therapist, a speech therapist, a social worker, a nurse coordinator for palliative care, a family support coordinator, the NICU Nurse Manager, a hospital chaplain, mid-level providers, bedside nurses, a nurse quality improvement leader and the leaders and database manager for the quality improvement project. When needed for specific patients, a bioethicist was included.ResultsOne year after implementing the project, the average duration of hospitalisation had decreased by 6.5 days. Cause-related readmission rates decreased from 3.33% to 0.95%. Parent satisfaction scores did not change significantly.ConclusionsWeekly multidisciplinary meetings to coordinate and provide continuity of care for medically complex neonates in our NICU was associated with improved patient outcomes.

and for the PENUT Consortium BACKGROUND: Outcomes of extremely low gestational age neonates (ELGANs) may be adversely impacted by packed red blood cell (pRBC) transfusions. We investigated the impact of transfusions on neurodevelopmental outcome in the Preterm Erythropoietin (Epo) Neuroprotection (PENUT) Trial population. METHODS: This is a post hoc analysis of 936 infants 24-0/6 to 27-6/7 weeks' gestation enrolled in the PENUT Trial. Epo 1000 U/kg or placebo was given every 48 h × 6 doses, followed by 400 U/kg or sham injections 3 times a week through 32 weeks postmenstrual age. Six hundred and twenty-eight (315 placebo, 313 Epo) survived and were assessed at 2 years of age. We evaluated associations between BSID-III scores and the number and volume of pRBC transfusions. RESULTS: Each transfusion was associated with a decrease in mean cognitive score of 0.96 (95% CI of [−1.34, −0.57]), a decrease in mean motor score of 1.51 (−1.91, −1.12), and a decrease in mean language score of 1.10 (−1.54, −0.66). Significant negative associations between BSID-III score and transfusion volume and donor exposure were observed in the placebo group but not in the Epo group. CONCLUSIONS: Transfusions in ELGANs were associated with worse outcomes. We speculate that strategies to minimize the need for transfusions may improve outcomes.

on behalf of the PENUT Trial Consortium* Objective To evaluate whether extremely low gestational age neonates (ELGANs) randomized to erythropoietin have better or worse kidney-related outcomes during hospitalization and at 22-26 months of corrected gestational age (cGA) compared with those randomized to placebo. Study designWe performed an ancillary study to a multicenter double-blind, placebo-controlled randomized clinical trial of erythropoietin in ELGANs. ResultsThe prevalence of severe (stage 2 or 3) acute kidney injury (AKI) was 18.2%. We did not find a statistically significant difference between those randomized to erythropoietin vs placebo for in-hospital primary (severe AKI) or secondary outcomes (any AKI and serum creatinine/cystatin C values at days 0, 7, 9, and 14). At 22-26 months of cGA, 16% of the cohort had an estimated glomerular filtration rate (eGFR) <90 mL/min/1.73 m 2 , 35.8% had urine albumin/creatinine ratio >30 mg/g, 23% had a systolic blood pressure (SBP) >95th percentile for age, and 40% had a diastolic blood pressure (DBP) >95th percentile for age. SBP >90th percentile occurred less often among recipients of erythropoietin (P < .04). This association remained even after controlling for gestational age, site, and sibship (aOR 0.6; 95% CI 0.39-0.92). We did not find statistically significant differences between treatment groups in eGFR, albumin/creatinine ratio, rates of SBP >95th percentile, or DBP >90th or >95th percentiles at the 2 year follow-up visit.Conclusions ELGANs have high rates of in-hospital AKI and kidney-related problems at 22-26 months of cGA.Recombinant erythropoietin may protect ELGANs against long-term elevated SBP but does not appear to protect from AKI, low eGFR, albuminuria, or elevated DBP at 22-26 months of cGA.

Background Prenatal risk factors are related to poor health and developmental outcomes for infants, potentially via epigenetic mechanisms. We tested associations between person-centered prenatal risk profiles, cumulative prenatal risk models, and epigenome-wide DNA methylation (DNAm) in very preterm neonates. Methods We studied 542 infants from a multi-center study of infants born < 30 weeks postmenstrual age. We assessed 24 prenatal risk factors via maternal report and medical record review. Latent class analysis was used to define prenatal risk profiles. DNAm was quantified from neonatal buccal cells using the Illumina MethylationEPIC Beadarray. Results We identified three latent profiles of women: a group with few risk factors (61%) and groups with elevated physical (26%) and psychological (13%) risk factors. Neonates born to women in higher risk subgroups had differential DNAm at 2 CpG sites. Higher cumulative prenatal risk was associated with methylation at 15 CpG sites, 12 of which were located in genes previously linked to physical and mental health and neurodevelopment. Conclusion We observed associations between prenatal risk factors and DNAm in very preterm infants using both person-centered and cumulative risk approaches. Epigenetics offers a potential biological indicator of prenatal risk exposure.