[Dynamic observation of pulmonary function by plethysmography in preterm infants with bronchopulmonary dysplasia].

OBJECTIVE: To study the effect of bronchopulmonary dysplasia (BPD) on lung function in preterm infants. METHODS: According to the presence/absence or the severity of BPD, 72 preterm infants were divided into non-BPD group (n=44), mild BPD group (n=15) and moderate BPD group (n=13). Lung function was assessed by plethysmography on days 7, 14 and 28 after birth. RESULTS: The preterm infants in the three groups had gradual increases in tidal volume per kilogram (TV/kg), functional residual capacity (FRC), ratio of time to peak tidal expiratory flow to total expiratory time (%T-PF) and ratio of volume to peak tidal expiratory flow to total expiratory volume (%V-PF) on days 7, 14 and 28 after birth, while there were gradual reductions in effective airway resistance per kilogram (Reff/kg) and respiratory rate (RR) (P<0.05). Compared with the non-BPD group on days 7, 14 and 28 after birth, the mild and moderate BPD groups had significantly lower TV/kg, FRC, %T-PF, and %V-PF and significantly higher Reff/kg and RR (P<0.05). On day 7 after birth, the moderate BPD group had significantly higher airway resistance, Reff/kg and FRC/kg than the mild BPD group (P<0.05). CONCLUSIONS: There is a certain degree of pulmonary function impairment in preterm infants with BPD. Dynamic monitoring of lung function by plethysmography is useful for assessing lung development in the neonatal period in these infants.

Risk factors for necrotizing enterocolitis in very preterm infants: a case-control study in southwest China.

OBJECTIVE: The objective of this study is to investigate perinatal risk factors for necrotizing enterocolitis (NEC) in very preterm infants. METHODS: This retrospective study included all preterm infants with a gestational age <32 weeks attending our institution from 2013 to 2016. The NEC group comprised patients with NEC enrolled according to the inclusion criteria. Controls were selected from the database and were matched for gender, gestational age, and birth weight. Enumeration data are expressed as percentages (%) and were compared using the χ2 test. Quantitative data are expressed as the mean (standard deviation) and were compared using Student's t-test. Conditional logistic regression analyses were performed to identify the factors significantly associated with NEC. RESULTS: During the study period, 945 very preterm infants were admitted to the neonatal intensive care unit, of whom 46 (4.87%) acquired NEC. A total of 33 cases were enrolled in the NEC group, and 33 controls were selected from the database. Univariate analyses revealed significant differences between groups in the incidence of maternal placenta previa, neonatal infection symptoms, septicemia, and intravenous aminophylline administration (p < .05). Conditional logistic regression analysis demonstrated statistically significant associations of neonatal septicemia (odds ratio [OR] = 4.000, p = .043) and intravenous aminophylline (OR = 4.922, p = .035) with NEC. CONCLUSION: Neonatal septicemia and intravenous aminophylline use are risk factors associated with NEC development in very preterm infants.

Resveratrol suppresses hyperoxia-induced nucleocytoplasmic shuttling of SIRT1 and ROS production in PBMC from preterm infants in vitro.

OBJECTIVE: By assessing silent mating-type information regulation 2 homolog 1 (SIRT1) nucleocytoplasmic shuttling and reactive oxygen species (ROS) levels in peripheral blood mononuclear cells (PBMCs), this study aimed to explore the role of SIRT1 in premature infants after exposure to hyperoxia and assess the protective effects of resveratrol (Res). METHODS: Firstly, ROS levels as well as SIRT1 translocation and expression in PBMCs samples were evaluated from 40 premature infants with different oxygen amounts received at birth. Then, PBMCs, from additional 40 premature infants administered no oxygen at birth, were used to establish an in vitro model of hyperoxia. RESULTS: In infants that received O2 at birth, ROS and MDA levels, and SIRT1 translocation rates gradually increased in a concentration-dependent manner, while SIRT1 gradually decreased. In agreement, PBMCs cultured in vitro showed increased ROS levels after exposed to hyperoxia, SIRT1 translocation increased as well. However, treatment with Res resulted in opposite effects. CONCLUSION: Res inhibits ROS release in PBMCs from preterm infants exposed to hyperoxia, likely by preventing SIRT1 nucleocytoplasmic shuttling and increasing SIRT1 expression.