BackgroundNecrotizing enterocolitis (NEC) is a leading cause of death in preterm infants. Neonates weighing <1500 grams are at the highest risk for acquiring NEC, with a prevalence of nearly 7-10%, mortality up to 30%, and several long-term complications among survivors. Despite advancements in neonatal medicine, this disease remains a challenge to treat. The aim of this study is to investigate the effect of NEC on gut epithelial tight junctions and its barrier function using a NEC mouse model.MethodsThree-day old C57BL/6 mouse pups were fed with Esbilac formula every 3 hours and then subjected to hypoxia twice daily followed by cold stress. Dam fed pups from the same litters served as controls. Pups were observed and sacrificed 96 hours after the treatments and intestines were removed for experiments. The successful induction of NEC was confirmed by histopathology. Changes in tight junction proteins in NEC intestines were studied by western blotting and immunofluorescent microscopy using specific protein markers. The gut leakage in NEC was visualized using biotin tracer molecules.ResultsOur study results demonstrate that we induced NEC in >50% of experimental pups, pups lost nearly 40% of weight and their intestines showed gross changes and microscopic changes associated with NEC. There were inflammatory changes with loss of tight junction barrier function and disruption of tight junction claudin proteins in the intestines of NEC mouse model. We have demonstrated for the first time that NEC intestines develop increased leakiness as visualized by biotin tracer leakage.ConclusionsNEC leads to breakdown of epithelial barrier due to changes in tight junction proteins with increased leakiness which may explain the transmigration of microbes and microbial products from the gut lumen into the blood stream leading to sepsis like signs clinically witnessed.

Objectives Conventional neonatology practice is to place umbilical venous catheters (UVCs) in central position and to limit the use of low-lying catheters. Our objectives were to describe the practices and complications associated with UVCs and to evaluate the type of infusates used with either UVC position. Study Design A retrospective chart review was performed at four neonatal intensive care units to identify neonates who underwent UVC placement over a 2-year period. Infant demographics, UVC position, catheter days, fluid and medication characteristics, and specific complications were extracted. Results A total of 2,011 neonates who underwent UVC placement were identified during the 2-year period. Of these, 641 UVCs (31.9%) were identified in the low-lying position. Centrally positioned UVCs were associated with lower gestational age and were left in situ for a longer duration than low-lying UVCs. Infusions of hyperosmolar solutions and vasopressors were significantly higher in central UVCs, though they were used in a significant number of low-lying UVCs. Complications, while not statistically different, were three times higher in low-lying UVCs. Conclusion Despite conventional teaching, low-lying UVCs were used in nearly one-third of infants in this cohort. Parenteral nutrition, antibiotics, and vasopressors were infused through central and low-lying UVCs. There was no statistically significant difference in complication rates between UVC positions.

The use of silver nanoparticles (AgNP) raises safety concerns during susceptible life stages such as pregnancy. We hypothesized that acute intravenous exposure to AgNP during late stages of pregnancy will increase vascular tissue contractility, potentially contributing to alterations in fetal growth. Sprague Dawley rats were exposed to a single dose of PVP or Citrate stabilized 20 or 110nm AgNP (700μg/kg). Differential vascular responses and EC values were observed in myographic studies in uterine, mesenteric arteries and thoracic aortic segments, 24h post-exposure. Reciprocal responses were observed in aortic and uterine vessels following PVP stabilized AgNP with an increased force of contraction in uterine artery and increased relaxation responses in aorta. Citrate stabilized AgNP exposure increased contractile force in both uterine and aortic vessels. Intravenous AgNP exposure during pregnancy displayed particle size and vehicle dependent moderate changes in vascular tissue contractility, potentially influencing fetal blood supply.

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ObjectiveTo identify whether intraventricular hemorrhage (IVH) and cerebellar hemorrhage (CH) have common or divergent risk factors.Study DesignThis is a retrospective cross-sectional cohort of infants including all infants born <30 weeks from 2007–16. Comprehensive perinatal, and clinical factors were extracted from the medical record. Outborn infants, infants with major congenital anomaly, those transferred prior to discharge, and those with mixed or no brain injury were excluded. The remaining infants were divided into two groups: IVH only and cerebellar hemorrhage only.Continuous variables were evaluated with the Wilcoxon-Mann-Whitney Test, categorical variables were evaluated with Fisher’s Exact Test. Multinomial logistic regression was used to identify factors which predispose infants towards injury type more than another, holding other factors held constant.Results127 infants were included (CH n=27, IVH n=100). Compared to those with IVH, infants with CH were of lower EGA (p=0.03), lower birth weight (p=0.01), more often of multiple gestation (p=0.03), more frequently born emergently (p=0.03), had a greater number of ventilator days (p=0.03), received postnatal steroids more often (p=0.02), had a greater incidence of hemodynamically significant PDA, and less frequently had pulmonary hemorrhage (p=0.04)In multinomial regression analysis, three factors were identified which favored cerebellar hemorrhage over IVH: multiple gestation (RR 4.70, 95% CI 1.56–14.21, p<0.01), chorioamnionitis (RR 3.18, 95% CI 1.13–8.92, p=0.03), and emergent delivery (RR 4.14, 95% CI 1.48–11.55, p<0.01). Only advancing gestational favored IVH over cerebellar hemorrhage (RR 0.74, 95% CI 0.65–0.85, p<0.01).ConclusionsIVH and CH have unique risk factors. These results highlight the need to tailor neuroimaging surveillance to specific patient risk factors.