Premature infants exposed to hyperoxia suffer acute and long-term pulmonary consequences. Nevertheless, neonates survive hyperoxia better than adults. The factors contributing to neonatal hyperoxic tolerance are not fully elucidated. In contrast to adults, heme oxygenase (HO)-1, an endoplasmic reticulum (ER)-anchored protein, is abundant in the neonatal lung but is not inducible in response to hyperoxia. The latter may be important, because very high levels of HO-1 overexpression are associated with significant oxygen cytotoxicity in vitro. Also, in contrast to adults, HO-1 localizes to the nucleus in neonatal mice exposed to hyperoxia. To understand the mechanisms by which HO-1 expression levels and subcellular localization contribute to hyperoxic tolerance in neonates, lung-specific transgenic mice expressing high or low levels of full-length HO-1 (cytoplasmic, HO-1-FL(H) or HO-1-FL(L)) or C-terminally truncated HO-1 (nuclear, Nuc-HO-1-TR) were generated. In HO-1-FL(L), the lungs had a normal alveolar appearance and lesser oxidative damage after hyperoxic exposure. In contrast, in HO-1-FL(H), alveolar wall thickness with type II cell hyperproliferation was observed as well worsened pulmonary function and evidence of abnormal lung cell hyperproliferation in recovery from hyperoxia. In Nuc-HO-1-TR, the lungs had increased DNA oxidative damage, increased poly (ADP-ribose) polymerase (PARP) protein expression, and reduced poly (ADP-ribose) (PAR) hydrolysis as well as reduced pulmonary function in recovery from hyperoxia. These data indicate that low cytoplasmic HO-1 levels protect against hyperoxia-induced lung injury by attenuating oxidative stress, whereas high cytoplasmic HO-1 levels worsen lung injury by increasing proliferation and decreasing apoptosis of alveolar type II cells. Enhanced lung nuclear HO-1 levels impaired recovery from hyperoxic lung injury by disabling PAR-dependent regulation of DNA repair. Lastly both high cytoplasmic and nuclear expression of HO-1 predisposed to long-term abnormal lung cellular proliferation. To maximize HO-1 cytoprotective effects, therapeutic strategies must account for the specific effects of its subcellular localization and expression levels.

We investigated the relationship of neonatal and maternal serum creatinine (nSCr and mSCr, respectively) with various maternal/infant characteristics at different gestational ages (GA). We reviewed medical records of neonates admitted to NICU. We collected data on birth weight, GA, Apgar scores, medications, etc. Spearman’s test was used to analyze the correlation between serum creatinine and continuous variables, and the Mann-Whitney U and Kruskal-Wallis tests for continuous variables between groups. The changes in nSCr, mSCr, and nSCr/mSCr ratio because of gestational age and the points in gestational changes in trends were estimated using joinpoint trend analysis. From 614 neonate and mother pairs, we found that nSCr was significantly correlated with GA. However, mSCr at >28 wks decreased with GA. The nSCr/mSCr ratio was correlated with GA. In infants born <29 weeks, pregnancy-induced hypertension (PIH) (p = 0.000, β = 0.20) and mSCr (p = 0.000, β = 0.73) were significantly associated with nSCr. In term infants, maternal magnesium administration (p = 0.000, β = 0.25), respiratory distress syndrome (p = 0.013, β = 0.16), PIH (p = 0.005, β = 0.19), and mSCr (p = 0.000, β = 0.33) were significantly associated with nSCr. nSCr reflected mSCr at all gestational ages. The correlation between nSCr and mSCr in preterm infants (p = 0.000, β = 0.74) was stronger than in term infants (p = 0.000, β = 0.34).

To evaluate whether KL-6 concentration is a useful biomarker of the severity of respiratory syncytial virus (RSV) bronchiolitis, we determined KL-6 concentrations in patients with RSV bronchiolitis with or without chronic heart disease (CHD). We enrolled 52 patients who had been diagnosed with RSV bronchiolitis and required admission to the hospital at the Department of Pediatrics of Fukushima Medical University School of Medicine from 2004 to 2005. These patients were divided into two groups: Group 1 consisted of patients without any underlying disease, and Group 2 consisted of patients with CHD. These patients were assigned to three categories. Stage A consisted of patients without oxygen dosage, stage B of patients who required oxygen dosage, and stage C of patients required artificial respiration. We evaluated baseline characteristics, clinical features, and serum KL-6 concentration in Group 1, Group 2, and a control group (healthy infants without infection). Mean serum KL-6 concentrations in patients with RSV bronchiolitis were higher than those in the control group (471.8 +/- 236.9 and 127.1 +/- 69.1 U/ml, respectively). Mean serum KL-6 concentration was higher in Group 2 than in Group 1 (692.8 +/- 313.1 and 390.4 +/- 132.7 U/ml, respectively). Mean serum KL-6 concentrations were higher in stage C than in stages A and B, and mean serum KL-6 concentrations were higher in stage B than in stage A. These findings suggest that serum KL-6 is associated with the severity of RSV bronchiolitis and that it may be a useful biomarker for the severity of RSV bronchiolitis.

Bach1 newborn mice were well-recovered from hyperoxia-induced lung injury. This effect is likely achieved by the antioxidant/anti-inflammatory activity of HO-1 or by the transient overexpression of proinflammatory cytokines.

Background: Platelets participate in many physiological and pathological functions and some platelet parameters predict adult diseases. However, few studies report whether platelet parameters may reflect neonatal disease and mortality in a large cohort.Objective: We aimed to investigate whether platelet parameters could predict bronchopulmonary dysplasia (BPD), necrotizing enterocolitis (NEC), intraventricular hemorrhage (IVH), and NICU mortality. Study Design and Methods:This retrospective cohort study examined records from 2006 to 2017 at the neonatal intensive care unit (NICU) of Fukushima Medical University Hospital. We retrospectively investigated platelet count, plateletcrit (PCT), mean platelet volume (MPV), and platelet distribution width (PDW) on the first day of life in preterm newborns born <32 weeks' gestation admitted to our NICU from 2006 to 2017. Receiver operating characteristic (ROC) and multiple regression analyses, along with Cox proportional hazard modeling, identified independent predictors of morbidities and mortality in preterm newborns.Results: Of 1,501 neonates admitted to our NICU, a total of 305 preterm newborns were included in this study. Gestational age, birth weight, and Apgar score were significantly lower in non-survivors than in survivors. Platelet count, PCT, PDW and PMI did not differ significantly between the two groups, whereas mean MPV in non-survivors was significantly higher than in survivors (10.5 fl vs. 10.0 fl, p = 0.001). Multivariate Cox hazard modeling showed that shorter GA [HR: 0.628, 95% CI: 0.464-0.840, p = 0.003], male sex [HR: 0.269, 95% CI: 0.113-0.640, p = 0.001], and MPV [HR: 1.469, 95% CI: 1.046-2.063, p = 0.026] independently predicted overall survival. Per receiver operating curve, an MPV threshold of 10.2 fl. MPV predicts prognosis in neonates with a sensitivity of 72.4% and a specificity of 58.6% (AUC = 0.685, 95% CI: 0.600-0.789, p = 0.001). Furthermore, multivariate analysis revealed that platelet parameters were not associated Go et al. Platelet Parameters in Neonateswith BPD and NEC, whereas small for gestational age (SGA), Apgar score at 5 min, and low PCT were associated with intraventricular hemorrhage (IVH).Conclusion: This study demonstrates that low PCT predicts IVH, and MPV ≥ 10.2 fL correlates with mortality among infants born after <32 weeks' gestation.

Premature infants are often exposed to positive pressure ventilation and supplemental oxygen, which leads to the development of chronic lung disease (CLD). There are currently no standard serum biomarkers used for prediction or early detection of patients who go on to develop CLD. MicroRNAs (miRNAs) are a novel class of naturally occurring, short, noncoding substances that regulate gene expression at the posttranscriptional level and cause translational inhibition and/or mRNA degradation and present in body fluids packaged in extracellular vesicles (EVs), rendering them remarkably stable. Our aim was to evaluate miRNAs identified in serum EVs of premature infants as potential biomarkers for CLD. Serum EVs were extracted from premature infants at birth and on the 28th day of life (DOL). Using a human miRNA array, we identified 62 miRNAs that were universally expressed in CLD patients and non-CLD patients. Of the 62 miRNAs, 59 miRNAs and 44 miRNAs were differentially expressed on DOL0 and DOL28 in CLD and non-CLD patients, respectively. Of these miRNAs, serum EV miR-21 was upregulated in CLD patients on DOL28 compared with levels at birth and downregulated in non-CLD patients on DOL28 compared with levels at birth. In neonatal mice exposed to hyperoxia for 7days, as a model of CLD, five miRNAs (miR-34a, miR-21, miR-712, miR-682, and miR-221) were upregulated, and 7 miRNAs (miR-542–5p, miR-449a, miR-322, miR-190b, miR-153, miR-335–3p, miR-377) were downregulated. MiR-21 was detected as a common miRNA that changed in CLD patients and in the hyperoxia exposed mice. We conclude that EV miR-21 may be a biomarker of CLD.

Bronchopulmonary dysplasia (BPD) is the most common morbidity complicating preterm birth. Red blood cell distribution width (RDW), a measure of the variation red blood cell size, could reflect oxidative stress and chronic inflammation in many diseases such as cardiovascular, pulmonary, and other diseases. The objectives of the present study were to evaluate perinatal factors affecting RDW and to validate whether RDW could be a potential biomarker for BPD. A total of 176 preterm infants born at < 30 weeks were included in this study. They were categorized into BPD (n = 85) and non-BPD (n = 91) infants. RDW at birth and 14 days and 28 days of life (DOL 14, DOL 28) were measured. Clinical data were obtained from all subjects at Fukushima Medical University (Fukushima, Japan). The mean RDW at birth, DOL 14 and DOL 28 were 16.1%, 18.6%, 20.1%, respectively. Small for gestational age (SGA), chorioamnionitis (CAM), hypertensive disorders of pregnancy (HDP), gestational age and birth weight were significantly associated with RDW at birth. SGA, BPD and red blood cell (RBC) transfusion before DOL 14 were associated with RDW at DOL 14. BPD and RBC transfusion before DOL 14 were associated with RDW at DOL 28. Compared with non-BPD infants, mean RDW at birth DOL 14 (21.1% vs. 17.6%, P < 0.001) and DOL 28 (22.2% vs. 18.2%, P < 0.001) were significantly higher in BPD infants. Multivariate analysis revealed that RDW at DOL 28 was significantly higher in BPD infants (P = 0.001, odds ratio 1.63; 95% CI 1.22–2.19). Receiver operating characteristic analysis for RDW at DOL 28 in infants with and without BPD yielded an area under the curve of 0.87 (95% CI 0.78–0.91, P < 0.001). RDW at DOL 28 with mild BPD (18.3% vs. 21.2%, P < 0.001), moderate BPD (18.3% vs. 21.2%, P < 0.001), and severe BPD (18.3% vs. 23.9%, P < 0.001) were significantly higher than those with non-BPD, respectively. Furthermore, there are significant differences of RDW at DOL 28 between mild, moderate, and severe BPD. In summary, we conclude that RDW at DOL 28 could serve as a biomarker for predicting BPD and its severity. The mechanism by which RDW at DOL 28 is associated with the pathogenesis of BPD needs further elucidation.

Background Although disseminated intravascular coagulation (DIC) is a critical disease, there is few gold standard interventions in neonatal medicine. The aim of this study is to reveal factors affecting neonatal DIC at birth and to assess the effectiveness of rTM and FFP for DIC in neonates at birth. Methods We retrospectively evaluated DIC score on the first day of life in neonates with underlying conditions associated with DIC. DIC in neonates was diagnosed according to Japan Society of Obstetrical, Gynecological & Neonatal Hematology 2016 neonatal DIC criteria. Results Comparing neonates with DIC scores of ≥3 (n = 103) to those < 3 (n = 263), SGA, birth asphyxia, low Apgar score, hemangioma, hydrops, PIH, and PA were statistically increased. Among 55 neonates underwent DIC treatment, 53 had birth asphyxia and 12 had intraventricular hemorrhage. Forty-one neonates received FFP or a combination of FFP and antithrombin (FFP group), while 14 neonates received rTM or a combination of rTM, FFP, and antithrombin (rTM group). DIC score before treatment in the rTM group was significantly higher than in the FFP group (4.7 vs 3.6, P < 0.05). After treatment, DIC scores in both groups were significantly reduced on Day 1 and Day 2 (P < 0.05). Conclusions Among various factors associated with DIC in neonates at birth, birth asphyxia is particularly significant. Furthermore, rTM in combination with FFP therapy was effective for neonatal DIC at birth.