[Risk factors for bronchopulmonary dysplasia in twin preterm infants: a multicenter study]. / åŒèƒŽæ—©äº§å„¿æ”¯æ°”ç®¡è‚ºå‘è‚²ä¸è‰¯å±é™©å› ç´ åˆ†æžï¼šä¸€é¡¹å¤šä¸­å¿ƒç ”ç©¶.

OBJECTIVES: To investigate the risk factors for bronchopulmonary dysplasia (BPD) in twin preterm infants with a gestational age of <34 weeks, and to provide a basis for early identification of BPD in twin preterm infants in clinical practice. METHODS: A retrospective analysis was performed for the twin preterm infants with a gestational age of <34 weeks who were admitted to 22 hospitals nationwide from January 2018 to December 2020. According to their conditions, they were divided into group A (both twins had BPD), group B (only one twin had BPD), and group C (neither twin had BPD). The risk factors for BPD in twin preterm infants were analyzed. Further analysis was conducted on group B to investigate the postnatal risk factors for BPD within twins. RESULTS: A total of 904 pairs of twins with a gestational age of <34 weeks were included in this study. The multivariate logistic regression analysis showed that compared with group C, birth weight discordance of >25% between the twins was an independent risk factor for BPD in one of the twins (OR=3.370, 95%CI: 1.500-7.568, P<0.05), and high gestational age at birth was a protective factor against BPD (P<0.05). The conditional logistic regression analysis of group B showed that small-for-gestational-age (SGA) birth was an independent risk factor for BPD in individual twins (OR=5.017, 95%CI: 1.040-24.190, P<0.05). CONCLUSIONS: The development of BPD in twin preterm infants is associated with gestational age, birth weight discordance between the twins, and SGA birth.

[Impact of assisted reproductive technology on birth weight discordance in twins]. / è¾ åŠ©ç”Ÿæ®–æŠ€æœ¯å¯¹åŒèƒŽå‡ºç”Ÿä½“é‡ä¸ä¸€è‡´çš„å½±å“.

OBJECTIVES: To explore the association between assisted reproductive technology (ART) and birth weight discordance in twins (BWDT). METHODS: A retrospective analysis was conducted on twin infants born between January 2011 and December 2020 at the Third Affiliated Hospital of Guangzhou Medical University, with complete basic birth data. The impact of ART on the occurrence of BWDT was identified by the multivariate logistic regression analysis. RESULTS: A total of 3 974 pairs of twins were included, with 1 431 conceived naturally and 2 543 through ART. Neonates in the ART group had higher birth weights than those in the naturally conceived group (P<0.001). The incidence of BWDT was lower in the ART group compared to the naturally conceived group (16.17% vs 21.09%, P<0.001). The multivariate logistic regression analysis, adjusting for confounding factors such as maternal age, parity, pre-pregnancy body mass index, gestational diabetes, hypothyroidism, gestational age, and chorionic properties, showed no significant difference in the risk of BWDT between the ART and naturally conceived groups (P>0.05). CONCLUSIONS: ART is not associated with the risk of BWDT.

Short term outcomes of extremely low birth weight infants from a multicenter cohort study in Guangdong of China.

With the increase in extremely low birth weight (ELBW) infants, their outcome attracted worldwide attention. However, in China, the related studies are rare. The hospitalized records of ELBW infants discharged from twenty-six neonatal intensive care units in Guangdong Province of China during 2008-2017 were analyzed. A total of 2575 ELBW infants were enrolled and the overall survival rate was 55.11%. From 2008 to 2017, the number of ELBW infants increased rapidly from 91 to 466, and the survival rate improved steadily from 41.76% to 62.02%. Increased survival is closely related to birth weight (BW), regional economic development, and specialized hospital. The incidence of complications was neonatal respiratory distress syndrome (85.2%), oxygen dependency at 28 days (63.7%), retinopathy of prematurity (39.3%), intraventricular hemorrhage (29.4%), necrotizing enterocolitis (12.0%), and periventricular leukomalacia (8.0%). Among the 1156 nonsurvivors, 90.0% of infants died during the neonatal period (≤ 28 days). A total of 768 ELBW infants died after treatment withdrawal, for reasons of economic and/or poor outcome. The number of ELBW infants is increasing in Guangdong Province of China, and the overall survival rate is improving steadily.

[Sex differences in clinical outcomes of extremely preterm infants/extremely low birth weight infants: a propensity score matching study]. / è¶ æ—©äº§å„¿/è¶ ä½Žå‡ºç”Ÿä½“é‡å„¿ä¸´åºŠç»“å±€çš„æ€§åˆ«å·®å¼‚ï¼šä¸€é¡¹å€¾å‘æ€§è¯„åˆ†åŒ¹é ç ”ç©¶.

OBJECTIVES: To study the effect of sex on the clinical outcome of extremely preterm infants (EPIs)/extremely low birth weight infants (ELBWIs) by propensity score matching. METHODS: A retrospective analysis was performed for the medical data of 731 EPIs or ELBWIs who were admitted from January 1, 2011 to December 31, 2020. These infants were divided into two groups: male and female. A propensity score matching analysis was performed at a ratio of 1:1. The matching variables included gestational age, birth weight, percentage of withdrawal from active treatment, percentage of small-for-gestational-age infant, percentage of use of pulmonary surfactant, percentage of 1-minute Apgar score ≤3, percentage of mechanical ventilation, duration of mechanical ventilation, percentage of antenatal use of inadequate glucocorticoids, and percentage of hypertensive disorders in pregnancy. The two groups were compared in the incidence rate of main complications during hospitalization and the rate of survival at discharge. RESULTS: Before matching, compared with the female group, the male group had significantly higher incidence rates of neonatal respiratory distress syndrome, bronchopulmonary dysplasia (BPD), severe intraventricular hemorrhage, periventricular leukomalacia, necrotizing enterocolitis, and patent ductus arteriosus (P<0.05), while after matching, the male group only had a significantly higher incidence rate of BPD than the female group (P<0.05). There was no significant difference in the rate of survival at discharge between the two groups before and after matching (P>0.05). CONCLUSIONS: Male EPIs/ELBWIs have a higher risk of BPD than female EPIs/ELBWIs, but male and female EPIs/ELBWIs tend to have similar outcomes.

Incidence of extrauterine growth retardation and its risk factors in very preterm infants during hospitalization: a multicenter prospective study. / ä½é™¢æžæ—©äº§å„¿å®«å¤–ç”Ÿé•¿è¿Ÿç¼“åŠç›¸å ³å› ç´ çš„å¤šä¸­å¿ƒå‰çž»æ€§ç ”ç©¶.

OBJECTIVES: To investigate the incidence of extrauterine growth retardation (EUGR) and its risk factors in very preterm infants (VPIs) during hospitalization in China. METHODS: A prospective multicenter study was performed on the medical data of 2 514 VPIs who were hospitalized in the department of neonatology in 28 hospitals from 7 areas of China between September 2019 and December 2020. According to the presence or absence of EUGR based on the evaluation of body weight at the corrected gestational age of 36 weeks or at discharge, the VPIs were classified to two groups: EUGR group (n=1 189) and non-EUGR (n=1 325). The clinical features were compared between the two groups, and the incidence of EUGR and risk factors for EUGR were examined. RESULTS: The incidence of EUGR was 47.30% (1 189/2 514) evaluated by weight. The multivariate logistic regression analysis showed that higher weight growth velocity after regaining birth weight and higher cumulative calorie intake during the first week of hospitalization were protective factors against EUGR (P<0.05), while small-for-gestational-age birth, prolonged time to the initiation of total enteral feeding, prolonged cumulative fasting time, lower breast milk intake before starting human milk fortifiers, prolonged time to the initiation of full fortified feeding, and moderate-to-severe bronchopulmonary dysplasia were risk factors for EUGR (P<0.05). CONCLUSIONS: It is crucial to reduce the incidence of EUGR by achieving total enteral feeding as early as possible, strengthening breastfeeding, increasing calorie intake in the first week after birth, improving the velocity of weight gain, and preventing moderate-severe bronchopulmonary dysplasia in VPIs.

Clinical treatment outcomes and their changes in extremely preterm twins: a multicenter retrospective study in Guangdong Province, China. / è¶ æœªæˆç†ŸåŒèƒŽå„¿ä¸´åºŠæ•‘æ²»ç»“å±€åŠå˜åŒ–åˆ†æžï¼šä¸€é¡¹å¹¿ä¸œçœå¤šä¸­å¿ƒå›žé¡¾æ€§ç ”ç©¶.

OBJECTIVES: To investigate the clinical treatment outcomes and the changes of the outcomes over time in extremely preterm twins in Guangdong Province, China. METHODS: A retrospective analysis was performed for 269 pairs of extremely preterm twins with a gestational age of <28 weeks who were admitted to the department of neonatology in 26 grade A tertiary hospitals in Guangdong Province from January 2008 to December 2017. According to the admission time, they were divided into two groups: 2008-2012 and 2013-2017. Besides, each pair of twins was divided into the heavier infant and the lighter infant subgroups according to birth weight. The perinatal data of mothers and hospitalization data of neonates were collected. The survival rate of twins and the incidence rate of complications were compared between the 2008-2012 and 2013-2017 groups. RESULTS: Compared with the 2008-2012 group, the 2013-2017 group (both the heavier infant and lighter infant subgroups) had lower incidence rates of severe asphyxia and smaller head circumference at birth (P<0.05). The mortality rates of both of the twins, the heavier infant of the twins, and the lighter infant of the twins were lower in the 2013-2017 group compared with the 2008-2012 group (P<0.05). Compared with the 2008-2012 group, the 2013-2017 group (both the heavier infant and lighter infant subgroups) had lower incidence rates of pulmonary hemorrhage, patent ductus arteriosus (PDA), periventricular-intraventricular hemorrhage (P-IVH), and neonatal respiratory distress syndrome (NRDS) and a higher incidence rate of bronchopulmonary dysplasia (P<0.05). CONCLUSIONS: There is a significant increase in the survival rate over time in extremely preterm twins with a gestational age of <28 weeks in the 26 grade A tertiary hospitals in Guangdong Province. The incidences of severe asphyxia, pulmonary hemorrhage, PDA, P-IVH, and NRDS decrease in both the heavier and lighter infants of the twins, but the incidence of bronchopulmonary dysplasia increases. With the improvement of diagnosis and treatment, the multidisciplinary collaboration between different fields of fetal medicine including prenatal diagnosis, obstetrics, and neonatology is needed in the future to jointly develop management strategies for twin pregnancy.

Umbilical Cord Blood-Derived Exosomes From Very Preterm Infants With Bronchopulmonary Dysplasia Impaired Endothelial Angiogenesis: Roles of Exosomal MicroRNAs.

Premature infants have a high risk of bronchopulmonary dysplasia (BPD), which is characterized by abnormal development of alveoli and pulmonary vessels. Exosomes and exosomal miRNAs (EXO-miRNAs) from bronchoalveolar lavage fluid are involved in the development of BPD and might serve as predictive biomarkers for BPD. However, the roles of exosomes and EXO-miRNAs from umbilical cord blood of BPD infants in regulating angiogenesis are yet to be elucidated. In this study, we showed that umbilical cord blood-derived exosomes from BPD infants impaired angiogenesis in vitro. Next-generation sequencing of EXO-miRNAs from preterm infants without (NBPD group) or with BPD (BPD group) uncovered a total of 418 differentially expressed (DE) EXO-miRNAs. These DE EXO-miRNAs were primarily enriched in cellular function-associated pathways including the PI3K/Akt and angiogenesis-related signaling pathways. Among those EXO-miRNAs which are associated with PI3K/Akt and angiogenesis-related signaling pathways, BPD reduced the expression of hsa-miR-103a-3p and hsa-miR-185-5p exhibiting the most significant reduction (14.3% and 23.1% of NBPD group, respectively); BPD increased hsa-miR-200a-3p expression by 2.64 folds of the NBPD group. Furthermore, overexpression of hsa-miR-103a-3p and hsa-miR-185-5p in normal human umbilical vein endothelial cells (HUVECs) significantly enhanced endothelial cell proliferation, tube formation, and cell migration, whereas overexpressing hsa-miR-200a-3p inhibited these cellular responses. This study demonstrates that exosomes derived from umbilical cord blood of BPD infants impair angiogenesis, possibly via DE EXO-miRNAs, which might contribute to the development of BPD.

[Effect of weight growth velocity in the early stage after birth on neurodevelopment of preterm infants at the corrected age of 12 months].

OBJECTIVE: To study the effect of weight growth velocity in the early stage after birth on the neurodevelopment of preterm infants at the corrected age of 12 months. METHODS: Related data were collected from the preterm infants who were discharged from the Department of Neonatology, Third Affiliated Hospital of Guangzhou Medical University, from July 1, 2015 to December 31, 2019 and were followed up at the outpatient service of high-risk infants. According to the weight growth velocity from birth to the corrected gestational age of 40 weeks, the infants were divided into two groups: low velocity [< 10 g/(kg·d); n=21] and high velocity [≥10 g/(kg·d); n=87]. At the corrected ages of 3, 6, and 12 months, Gesell Developmental Schedules were used to evaluate and compare neurodevelopment between the two groups. RESULTS: At the corrected age of 12 months, the low velocity group had a significantly lower score of fine motor (P < 0.05) and a significantly higher abnormal rate of language ability score compared with high velocity (P < 0.05). For the preterm infants with a birth weight of < 1 500 g or ≥1 500 g, the low velocity group had a significantly lower score of fine motor than the high velocity group (P < 0.05); for the preterm infants with a birth weight of ≥1 500 g, the low velocity group had a significantly higher abnormal rate of language ability score than the high velocity group (P < 0.05). CONCLUSIONS: The weight growth velocity from birth to the corrected age of 40 weeks affects the development of fine motor and language in preterm infants at the corrected age of 12 months; however it needs to be further verified by large-sample studies.

Postnatal high-protein diet improves learning and memory in premature rats via activation of mTOR signaling.

PURPOSE: The present study investigated whether a high-protein diet affects spatial learning and memory in premature rats via modulation of mammalian target of rapamycin (mTOR) signaling. METHODS: Pre- and full-term Sprague-Dawley pups were fed a normal (18% protein) or high-protein (30% protein) diet (HPD) for 6 or 8 weeks after weaning. Spatial learning and memory were tested in the Morris water maze at week 6 and 8. The activation of mTOR signaling pathway components was evaluated by western blotting. RESULTS: Spatial memory performance of premature rats consuming a normal and HPD was lower than that of full-term rats on the same diet at 6 weeks, and was associated with lower levels of ribosomal protein S6 kinase p70 subtype (p70S6K) and initiation factor 4E-binding protein 1 (4EBP1) phosphorylation in the hippocampus. Spatial memory was improved in 8-week-old premature rats on an HPD as compared to those on a normal diet. Premature rats on an HPD had p70S6K and 4EBP1 phosphorylation levels in the hippocampus that were comparable to those of full-term rats on an HPD. CONCLUSION: Long-term consumption of a protein-rich diet can restore the impairment in learning and memory in pre-term rats via upregulation of mTOR/p70S6K signaling.

[Comparative analysis of risk factors for preterm and small-for-gestational-age births].

OBJECTIVE: To compare the risk factors between preterm and small-for-gestational-age (SGA) births. METHODS: A total of 1 270 newborns who had no obstetric risk factors or maternal diseases were enrolled in this study. Their mothers' stature, body weight, passive smoking, and history of abnormal pregnancy were investigated using the self-designed questionnaire. The infants were divided into four groups: preterm, appropriate-for-gestational-age (AGA), SGA, and term infants. Multivariate logistic regression analysis was performed to compare the risk factors between preterm and SGA births. RESULTS: A weight gain less than 9 kg during pregnancy increased the risks of preterm (OR=1.63, 95% CI: 1.12-2.07) and SGA (OR=1.92, 95% CI: 1.56-2.58). The histories of abortion (OR=1.46, 95% CI: 1.09-1.93) and preterm birth (OR=2.63, 95% CI: 1.81-3.92) were independent risk factors for preterm births, while low pre-pregnancy body mass index (<18.5) (OR=2.16, 95% CI: 1.53-3.16), short stature (<1.55 m) (OR=2.46, 95% CI: 1.78-3.48), and passive smoking (OR=2.24, 95% CI: 1.65-2.98) were independent risk factors for SGA births. CONCLUSIONS: Due to different risk factors between preterm and SGA births, specific preventive measures should be taken pertinently to reduce the incidence of the two bad pregnancy outcomes.

[Effects of feeding patterns after hospital discharge on increase rates of growth indices in preterm and low-birth-weight infants within 3 months after birth].

OBJECTIVE: To study the effects of post-discharge formula (PDF) for preterm infants, breast milk (BM) and term infant formula (TF) on increase rates of body weight, length and head circumference in preterm and low-birth-weight infants (PLBWIs) from discharge to 3 months after birth, and to provide a reference for the choice of feeding pattern for PLBWIs. METHODS: A total of 407 PLBWIs discharged from the newborn departments of ten hospitals in Guangzhou City and Foshan City in Guangdong Province, China were chosen for this study. According to feeding pattern, they were assigned to three groups: PDF-fed (n=258), BM-fed (n=58) and TF-fed (n=91). Their body weight, length and head circumference were measured at 3 months after birth, and the increase rates of growth indices relative to baseline values (at birth) were calculated and compared. RESULTS: At 3 months after birth, the PDF-fed group had significantly greater body weight, length and head circumference than the BM-fed and TF-fed groups (P<0.05). The increase rates of body weight and length were significantly higher in the PDF-fed group than in the BM-fed and TF-fed groups (P<0.05). CONCLUSIONS: Compared with those fed with BM and TF after discharge, the PDF-fed PLBWIs have higher increase rates of body weight and length and show greater body weight and length at 3 months after birth. However, further study is needed to investigate the long-term effects.

[Analysis of de novo copy number variations in a family affected with autism spectrum disorders using high-resolution array-based comparative genomic hybridization].

OBJECTIVE: To analyze de novo copy number variations (CNVs) in a Chinese family affected with autism spectrum disorders (ASD). METHODS: Affymetrix Cytogenetics Whole Genome 2.7M Array assay was performed to identify potential CNVs in four members from the family. RESULTS: A total of 89 de novo CNV regions were identified in the autistic siblings. The CNV regions in total have exceeded 1/1000 of the lengths of chromosomes 5, 11 and 14. In addition, de novo CNV regions were also identified at 3p26.1, 4q22.2, and 5p15.2, which encompassed 10 genes associated with nerve development including GRM7, GRID2 and CTNND2. CONCLUSION: A number of nerve development associated genes were at the de novo CNV sites, which may provide new clues for genetic research of ASD. High-resolution array-comparative genomic hybridization is an effective method for detecting submicroscopic chromosomal imbalances.

Epidemiologic survey on hospitalized neonates in China.

OBJECTIVE: To carry out a nationwide epidemiologic survey on the neonates in urban hospitals with an attempt to understand the disease spectrum and treatment outcomes of hospitalized neonates in China. METHODS: The clinical data of 43,289 hospitalized neonates from 86 hospitals in 47 Chinese cities (22 provinces) between January 1, 2005 and December 31, 2005 were retrospectively analyzed. RESULTS: The male:female ratio was 1.73:1. Premature infants accounted for 26.2% of the hospitalized neonates, which was higher than that reported in 2002 (19.7%). The top three diseases during the neonatal period were jaundice, pneumonia, and hypoxic-ischemic encephalopathy. The incidences of pneumonia, meconium aspiration syndrome, and bilirubin encephalopathy in term infants were higher than those in premature infants, while the incidences of asphyxia, respiratory distress syndrome, and pulmonary hemorrhage in term infants were lower than those in premature infants. The incidences of asphyxia, small for gestational age infant, and wet lung were higher in neonates whose mother had pregnancy induced hypertension. The outcomes of these hospitalized neonates included: recovered, 63.9%; improved, 27.3%; discharged due to the family's own decisions, 7.6%, and died, 1.2%. Nearly half (46.4%) of the neonatal death occurred within 24 hrs after admission. CONCLUSION: The incidence of premature birth shows an increasing trend among hospitalized neonates. Since the neonatal deaths mainly occur within 24 hrs after admission, monitoring during this period should be enhanced.

[Raman characterization of high-pressure phase transition in AlN nanowires].

High-pressure phase transition of AlN nanowires was investigated in the range of 0-33.1 GPa by in situ Raman spectrum method in diamond anvil cell (DAC). The A1 (LO) vibration mode exhibits considerably asymmetry and broadening, indicating the occurrence of wurtzite-to-rocksalt phase transition. The Raman signal of high-pressure phase can be assigned to the disorder activated Raman scattering of rocksalt AlN. After fully releasing pressure, the Raman characterization of high-pressure phase was quenched. According to the pressure dependence of phonon frequency of AlN nanowires, the difference of transiton path between AlN nanowires and bulk materials was discussed and the mode Grüneisen parameters were determined.

[Establishment of a neonatal piglet model of multiple organ dysfunction syndrome].

OBJECTIVE: To study the reliability of establishing a neonatal piglet model of multiple organ dysfunction syndrome (MODS) by cecal ligation and puncture (CLP). METHODS: Fourteen neonatal piglets were randomly assigned into Experiment group (n=9) and Control group (n=5). MODS model was established in the piglets from the Experiment group by CLP. The Control group underwent a sham-operation. Serum biochemical parameters (ALT, AST, ALB, BUN, Cr, CK-MB and lactic acid), blood platelet counting and blood gas analysis(PaO2 and PaCO2) were tested at 0, 24, 48, 72, 96, and 120 hrs after operation. The histomorphological changes of important vital organs were examined by hematoxylin-eosin staining under a light microscope. RESULTS: The levels of serum ALT, AST, BUN, Cr, CK-MB and lactic acid in the Experiment group began to increase 24 hrs after operation. Significant differences were observed between the Experiment and the Control group at 48 hrs in ALT (83.0 +/- 9.3 U/L vs 57.8 +/- 15.8 U/L), AST (348.8 +/- 132.9 U/L vs 106.4 +/- 12.5 U/L), BUN (10.5 +/- 2.5 micromol/L vs 4.3 +/- 1.0 micromol/L), Cr (79.2 +/- 9.0 micromol/L vs 53.6 +/- 6.8 micromol/L), CK-MB (5152.0 +/- 1 857.8 U/L vs 1243.0 +/- 354.5 U/L), and lactic acid (12.3 +/- 4.0 mmol/L vs 4.6 +/- 1.5 mmol/L) (P < 0.01). The high levels of the above parameters persisted until 96 hrs after operation in the Experiment group and then decreased but were still higher than those at 0 h after operation. After operation, the blood platelet counting decreased significantly at 96 hrs, and PaO2 decrease and PaCO2 increase were observed at 48 hrs in the Experiment group compared with the Control group. All animals, except one, in the Experiment group died within 120 hrs after operation (with the MODS incidence of 56%), while none died in the Control group. The tissue injuries with different degrees were observed in the lungs, liver, heart, kidneys and gastrointestinal tracts of the Experiment group. CONCLUSIONS: Neonatal piglet MODS model can be established successfully by CLP.