Predictive factors for rapid progression in preterm neonates with necrotizing enterocolitis.

Background: Necrotizing enterocolitis (NEC) is a devastating gastrointestinal emergency with significant mortality and morbidity rates. A subset of patients progressed rapidly and underwent surgical intervention within a short period. This study aimed to establish a model to predict the rapid progression of NEC in preterm neonates. Methods: A retrospective study was conducted to review neonates with NEC between December 2015 and April 2019 at the Guangzhou Women and Children's Medical Center. Rapidly progressive NEC was defined as the need for surgical intervention or death within 48 h of NEC onset. Patients were divided into two groups: rapidly progressive NEC (RP-NEC) and non-rapidly progressive NEC (nRP-NEC). Data on demographics, perinatal characteristics, examination variables, and radiographic findings at onset were collected. Results: A total of 216 preterm neonates with NEC were included in the study, of which 64 had RP-NEC and 152 had nRP-NEC. The mortality rates of patients with RP-NEC and nRP-NEC were 32.8% and 3.28%, respectively. Male sex (p-value, adjusted odds ratio [95% confidence interval]: 0.002, 3.43 [1.57, 7.53]), portal venous gas (0.000, 8.82 [3.73, 20.89]), neutrophils <2.0 × 109/L (0.005, 4.44 [1.59, 12.43]), pH <7.3 (7.2 ≤ pH < 7.3) (0.041, 2.95 [1.05, 8.31]), and pH <7.2 (0.000, 11.95 [2.97, 48.12]) at NEC onset were identified as independent risk factors for RP-NEC. An established model that included the four risk factors presented an area under the curve of 0.801 with 83% specificity and 66% sensitivity. Conclusion: Among preterm neonates with NEC, a significantly higher mortality rate was observed in those with rapid progression. It is recommended that close surveillance be performed in these patients, and we are confident that our established model can efficiently predict this rapid progression course.

Extracorporeal membrane oxygenation for congenital diaphragmatic hernia: how to begin?

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is critical for congenital diaphragmatic hernia (CDH), who fails to achieve adequate oxygenation with conventional management. We aim to evaluate initial experiences with ECMO support in a tertiary women and children's medical center in mainland China. METHODS: We retrospectively reviewed the establishment of ECMO for CDH Program in our center and analysis of five CDH neonates, who underwent repair during ECMO between December 2016 and December 2018. RESULTS: The first ECMO for CDH Program in our institution was established and managed by a multidisciplinary team since December 2016. An alert of ECMO was prenatally created for moderate-severe pulmonary hypoplasia. Of sixteen admissions prenatally diagnosed moderate-severe CDH, eight neonates (50%) required ECMO but five (31%) received eventually. Veno-arterial ECMO was established from 3 hours to 41 hours of age (median 20 h). All the five underwent CDH repair after a stabilization period on ECMO, which ranged from 12 h to 122 h (median 58 h). There were no clotting complications, related to coagulating during CDH repair. Bleeding was the most common complication. Cannula malposition was detected in one case. Their median ECMO duration was 437 (range 85-946) hours. Neonatal survival was 80% (4/5) and 3 survived (60%) in the first three months of life. CONCLUSIONS: Multidisciplinary team work, precise prenatal evaluation and skillful cannulation assist the successful beginning of ECMO for CDH. Our preliminary results would encourage other institutions, whose ECMO is not well-established.

Protective effects of activated protein C on neurovascular unit in a rat model of intrauterine infection-induced neonatal white matter injury.

Activated protein C (APC), a natural anticoagulant, has been reported to exert direct vasculoprotective, neural protective, anti-inflammatory, and proneurogenic activities in the central nervous system. This study was aimed to explore the neuroprotective effects and potential mechanisms of APC on the neurovascular unit of neonatal rats with intrauterine infection-induced white matter injury. Intraperitoneal injection of 300 µg/kg lipopolysaccharide (LPS) was administered consecutively to pregnant Sprague-Dawley rats at embryonic days 19 and 20 to establish the rat model of intrauterine infection- induced white matter injury. Control rats were injected with an equivalent amount of sterile saline on the same time. APC at the dosage of 0.2 mg/kg was intraperitoneally injected to neonatal rats immediately after birth. Brain tissues were collected at postnatal day 7 and stained with hematoxylin and eosin (H&E). Immunohistochemistry was used to evaluate myelin basic protein (MBP) expression in the periventricular white matter region. Blood-brain barrier (BBB) permeability and brain water content were measured using Evens Blue dye and wet/dry weight method. Double immunofluorescence staining and real-time quantitative PCR were performed to detect microglial activation and the expression of protease activated receptor 1 (PAR1). Typical pathological changes of white matter injury were observed in rat brains exposed to LPS, and MBP expression in the periventricular region was significantly decreased. BBB was disrupted and the brain water content was increased. Microglia were largely activated and the mRNA and protein levels of PAR1 were elevated. APC administration ameliorated the pathological lesions of the white matter and increased MBP expression. BBB permeability and brain water content were reduced. Microglia activation was inhibited and the PAR1 mRNA and protein expression levels were both down-regulated. Our results suggested that APC exerted neuroprotective effects on multiple components of the neurovascular unit in neonatal rats with intrauterine infection- induced white matter injury, and the underlying mechanisms might involve decreased expression of PAR1.

Neuroprotective effects of activated protein C on intrauterine inflammation-induced neonatal white matter injury are associated with the downregulation of fibrinogen-like protein 2/fibroleukin prothrombinase and the inhibition of pro-inflammatory cytokine expression.

Maternal intrauterine inflammation or infection is an important risk factor for neonatal cerebral white matter injury (WMI) and future neurological deficits. Activated protein C (APC), a natural anticoagulant, has been shown to exhibit anti-inflammatory, anti-apoptotic, profibrinolytic and cytoprotective activities. Recent studies have demonstrated that the novel prothrombinase, fibrinogen-like protein 2 (fgl2), contributes to the pathogenesis of a number of inflammatory diseases through the generation of fibrin. Thus, we hypothesized that APC may regulate coagulant and inflammatory processes and improve brain injury in an experimental rat model of intrauterine inflammation-induced WMI. The animal model was established by the administration of an intraperitoneal injection of lipopolysaccharide (LPS) to pregnant Sprague-Dawley rats on embryonic day (E)17 and E18. APC was administered intraperitoneally 30 min after the second LPS injection. The expression of fgl2 and the pro-inflammatory cytokines, tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1ß expression in the placentas and fetal brains was determined on E19. Nerve cell death, the brain water content and protease-activated receptor 1 (PAR1) and nuclear factor κB (NF-κB) p65 expression was detected in the fetal brains. WMI in the neonatal rat brains was evaluated by hematoxylin and eosin (H&E) staining and immunohistochemistry for myelin basic protein (MBP). The results revealed that APC markedly reduced the LPS-induced increase in fgl2 expression and fibrin deposition, as well as the production of the pro-inflammatory cytokines, TNF-α, IL-6 and IL-1ß, in the placentas and fetal brains. In addition, APC attenuated cerebral apoptosis and brain edema, downregulated PAR1 and NF-κB p65 expression in the fetal brains, and improved hypomyelination and structural disturbances in the periventricular area of the neonatal rat brains. Our observations provide evidence that APC attenuates fetal neuroinflammation and the associated secondary WMI in the developing brain by inhibiting the expression of fgl2 and pro-inflammatory mediators, suggesting that APC may be a potential therapeutic approach for intrauterine inflammation-induced neonatal brain injury.

IUGR with infantile overnutrition programs an insulin-resistant phenotype through DNA methylation of peroxisome proliferator-activated receptor-γ coactivator-1α in rats.

BACKGROUND: Intrauterine growth restriction (IUGR) followed by postnatal accelerated growth (CG-IUGR) is associated with long-term adverse metabolic consequences, and an involvement of epigenetic dysregulation has been implicated. Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) is a key orchestrator in energy homeostasis. We hypothesized that CG-IUGR programed an insulin-resistant phenotype through the alteration in DNA methylation and transcriptional activity of PGC-1α. METHODS: A CG-IUGR rat model was adopted using maternal gestational nutritional restriction followed by infantile overnutrition achieved by reducing the litter size. The DNA methylation was determined by pyrosequencing. The mRNA expression and mitochondrial content were assessed by real-time PCR. The insulin-signaling protein expression was evaluated by western blotting. RESULTS: Compared with controls, the CG-IUGR rats showed an increase in the DNA methylation of specific CpG sites in PGC-1α, and a decrease in the transcriptional activity of PGC-1α, mitochondrial content, protein level of PI3K and phosphorylated-Akt2 in liver and muscle tissues. The methylation of specific CpG sites in PGC-1α was positively correlated with fasting insulin concentration. CONCLUSION: IUGR followed by infantile overnutrition programs an insulin-resistant phenotype, possibly through the alteration in DNA methylation and transcriptional activity of PGC-1α. The genetic and epigenetic modifications of PGC-1α provide a potential mechanism linking early-life nutrition insult to long-term metabolic disease susceptibilities.