Prenatal pyrethroid pesticides exposure and neurodevelopment of 2-year-old children: a birth cohort study / 中华预防医学杂志

Objective: To investigate the influence and critical windows of prenatal exposure to pyrethroid pesticides (PYRs) on neurodevelopment of 2-year-old children. Methods: The subjects of this study were derived from the Xuanwei Birth Cohort. A total of 482 pregnant women who participated in the rural district of Xuanwei birth cohort from January 2016 to December 2018 were included. Maternal urinary concentrations of PYRs metabolites during 8-12 gestational weeks, 20-23 gestational weeks and 32-35 gestational weeks were measured with ultra high performance liquid chromatography system coupled with a tandem mass spectrometry detector. Child neurodevelopment was evaluated with the Bayley Scales of Infant and Toddler Development-Third Edition at 2 years of age. Multivariate linear regression models and binary logistic regression models were used to assess the association between PYRs exposure during pregnancy and children's neurodevelopment. Results: A total of 360 mother-child pairs had complete data on maternal urinary PYRs metabolites detection and children's neurodevelopment assessment. The detection rate of any one PYRs metabolites during the first, second and third trimester were 93.6% (337/360), 90.8% (327/360) and 94.2% (339/360), respectively. The neurodevelopmental scores of Cognitive, Language, Motor, Social-Emotional, and Adaptive Behavior of 2-year-old children were (102.3±18.9), (100.2±16.3), (102.0±20.3), (107.8±23.3) and (85.8±18.6) points, respectively. After controlling for confounding factors, 4-fluoro-3-phenoxybenzoic acid (4F3PBA, one of PYRs metabolites) exposure in the first trimester reduced Motor (β=-5.02, 95%CI: -9.08, -0.97) and Adaptive Behavior (β=-4.12, 95%CI:-7.92, -0.32) scores of 2-year-old children, and increased risk of developmental delay of adaptive behavior (OR=2.07, 95%CI:1.13-3.82). Conclusion: PYRs exposure during the first trimester of pregnancy may affect neurodevelopment of 2-year-old children, and the first trimester may be the critical window.

Clinical application of whole exome sequencing in monogenic hereditary disorders in critically ill newborns / 中国当代儿科杂志

OBJECTIVE@#To explore the value and significance of the clinical application of whole exome sequencing (WES) in monogenic hereditary disorders in critically ill newborns.@*METHODS@#The critically ill newborns in the neonatal intensive care unit with suspected hereditary diseases or unclear clinical diagnosis from June 2016 to December 2018 were enrolled. The whole blood samples from both newborns and parents were collected for WES. The detected genetic mutations were classified, the mutations associated with clinical phenotypes were searched for, and Sanger sequencing was performed to verify the mutations.@*RESULTS@#A total of 45 newborns were enrolled, including 22 males and 23 females, and the median age of onset was 2.0 days. Of the 45 newborns, 12 (27%) were confirmed with monogenic hereditary disorders by molecular diagnostics, and the median age at diagnosis was 31.5 days. Of the 12 newborns with monogenic hereditary disorders, 5 (42%) were partially associated with clinical phenotypes but confirmed with monogenic hereditary disorders by additional information supplement and analysis. The improvement rate of newborns with monogenic hereditary disorders was 67% (8/12) after treatment.@*CONCLUSIONS@#WES technology is a powerful tool for finding genetic mutations in monogenic hereditary disorders in critically ill newborns and can play a crucial role in clinical decision-making. However, a comprehensive interpretation of sequence data requires physicians to take the clinical phenotypes and the results of WES into consideration simultaneously.

A clinical study of growth and metabolism of small for gestational age infants / 中国当代儿科杂志

OBJECTIVE@#To study the differences in growth and metabolism between small for gestational age (SGA) infants and appropriate for gestational age (AGA) infants.@*METHODS@#A total of 1 370 preterm infants were enrolled in this study. According to the association between gestational age and birth weight, they were divided into SGA group with 675 infants and AGA group with 695 infants. The two groups were compared in terms of general conditions, physical growth and blood biochemical parameters.@*RESULTS@#The SGA group had a significantly longer length of hospital stay than the AGA group (P<0.05). Compared with the AGA group, the SGA group had significantly lower body weight, body weight Z score, and body length at discharge and significantly higher incidence rate of extrauterine growth retardation and growth rate of head circumference (P<0.05). Compared with the AGA group, the SGA group had significantly longer time to full enteral nutrition and duration of parenteral nutrition (P<0.05). Compared with the AGA group, the SGA group had significantly higher levels of albumin, prealbumin, and serum phosphorus on admission and total bile acid before discharge, as well as a significantly lower albumin level before discharge (P<0.05). The incidence rates of asphyxia, neonatal respiratory distress syndrome, myocardial damage, feeding intolerance, pneumonia, sepsis, hypoglycemia and hypothyroxinemia in the SGA group were significantly higher than in the AGA group (P<0.05).@*CONCLUSIONS@#Compared with AGA infants, SGA infants have significantly delayed physical development during hospitalization and significantly higher incidence rates of extrauterine growth retardation and related complications.

Levels of blood free carnitine in preterm infants with different gestational ages and birth weights / 中国当代儿科杂志

OBJECTIVE@#To examine blood concentrations of free carnitine (FC) in preterm infants with different gestational ages (GA) and birth weights (BW).@*METHODS@#A total of 3 368 preterm infants were enrolled as subjects. According to GA, they were divided into extremely preterm birth (EPTB) group (GA <28 weeks; n=39), very preterm birth (VPTB) group (28 ≤GA <32 weeks; n=405), moderately preterm birth (MPTB) group (32 ≤GA <34 weeks; n=507), and late preterm birth (LPTB) group (34 ≤GA <37 weeks; n=2 417); according to BW, they were divided into extremely low birth weight (ELBW) group (BW <1 000 g; n=36), very low birth weight (VLBW) group (1 000 g ≤BW <1 500 g; n=387), low birth weight (LBW) group (1 500 g ≤BW <2 500 g; n=1 873), and normal birth weight (NBW) group (2 500 g ≤ BW <4 000 g; n=1 072). Blood concentrations of FC were measured between 72 hours and 7 days after birth.@*RESULTS@#The EPTB and VPTB groups had significantly higher FC concentrations than the MPTB and LPTB groups (P<0.05), and the MPTB group had significantly higher FC concentrations than the LPTB group (P<0.05). The lower limit of the 95% medical reference range of FC increased with the reduction in GA. The ELBW and VLBW groups had significantly higher FC concentrations than the LBW and NBW groups (P<0.05). The LBW group had significantly higher FC concentrations than the NBW group (P<0.05). The lower limit of the 95% medical reference range of FC increased with the reduction in BW.@*CONCLUSIONS@#There is a significant increase in blood FC concentrations in very/extremely preterm infants and very/extremely low birth weight infants, and tend to decrease with the increases in GA and BW.

The Determination of Cut-off Value of TSH during Screening of Congenital Hypothyroidism in 6 Prefecture/City of Yunnan Province / 昆明医科大学学报

Objective To explore the positive cut-off value in neonatal screening for congenital hypothyroidism(CH)in the center of Neonatal Screening , so as to improve screening efficiency and reduce false positive rate. Methods Heel blood samples were taken from the newborns born after72 hours,dropped in special S&S903 filter paper and delivered to the neonatal screening center within the prescribed period of time.DELFIA was applied to detect the concentration of thyroid-stimulating hormone(TSH).Result Totally 529918 blood sample were screened from the 2012 to the 2016.Among them 529645 newborns were normal, 203 neonates were diagnosed with CH, 70 with high TSH hyperlipidemia, the total detection rate was 1:1941, and the incidence of CH was 1:2610. According to the results, the cut-off value of the screening of CH in the center of Neonatal Screening was 9.0 mIU/L, the sensitivity was 100％and specifility was 98.38％, misdiagnosis rate was 0％. Conclusion The cut-off value of CH was 9.0 mIU/L in the center of Neonatal Screening ,which is suitable for the people in 6 Prefecture/City of Yunnan Province , and also provides the basis for neonatal scree of CH in the future.

Effect of prone positioning on respiratory function in very preterm infants undergoing mechanical ventilation / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To explore the effect of prone positioning on respiratory function in very preterm infants undergoing mechanical ventilation.</p><p><b>METHODS</b>A total of 83 very preterm infants treated with mechanical ventilation were enrolled in the study and were randomly assigned to supine group and prone group. Four infants withdrew from the study and 79 infants completed treatment and observation (37 in the supine group and 42 in the prone group). Infants in both groups were mechanically ventilated in a volume assist-control mode. Infants in the prone group were ventilated in the supine position for 4 hours and in the prone position for 2 hours. Ventilator parameters, arterial blood gas analysis, and vital signs were recorded before grouping, every 6 hours in the supine group, and every hour after conversion into the prone position in the prone group, respectively.</p><p><b>RESULTS</b>Fraction of inspired oxygen (FiO), peak inspiratory pressure, mean inspiratory pressure, and duration of ventilation were significantly lower in the prone group than in the supine group (P<0.05); there were no significant differences in tidal volume or positive end-expiratory pressure between the two groups (P>0.05). The prone group had a significantly higher PO/FiO ratio but significantly lower oxygenation index and respiratory rate than the supine group (P<0.05). There were no significant differences in arterial oxygen tension, pH, base excess, heart rate, or mean blood pressure between the two groups (P>0.05).</p><p><b>CONCLUSIONS</b>Alternating ventilation between the prone position and supine position can improve oxygenation function, decrease the fraction of inspired oxygen, and shorten the duration of mechanical ventilation in very preterm infants undergoing mechanical ventilation.</p>

Epidemiological survey of childhood asthma in Kunming City, China / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the prevalence of childhood asthma, and to find the distribution characteristics, precipitating factors, diagnosis and treatment status, and to provide scientific data for improving the prevention and management of asthma in children in Kunming City, China.</p><p><b>METHODS</b>Children were selected by random cluster sampling. A standardized preliminary questionnaire was used for screening out possible patients in the survey. Diagnosis of asthma was confirmed by diagnostic criteria in suspected asthmatic children. Asthmatic children were further asked for past diagnosis and treatment with the questionnaire of asthma in children.</p><p><b>RESULTS</b>The total asthma incidence rate was 1.40%. The prevalence of asthma in male and female children was 1.89% and 0.88% respectively (P<0.05). Children aged 0-5 years old had a higher prevalence of asthma (1.69%) than that of school-age children (6-14 years old, 1.21%). In all asthmatic children, 51.3% were previously diagnosed with classical asthma or cough variant asthma, 26.0% were suffered attacks from December to February, and 54.0% were suffered attacks at midnight or dawn. Respiratory tract infection (87.3%) was the most common triggers of asthma exacerbation. Antibiotics were used in 80.0%, bronchodilators in 66.0%, inhaled corticosteroid in 64.0%. A peak flow meter for monitoring lung function was used in 17% of asthmatic children over 5 years old.</p><p><b>CONCLUSIONS</b>The prevalence of asthma is associated with age and gender in children aged 0-14 years old in Kunming City. Acute asthma attack occurs mostly in winter and at midnight or dawn. Respiratory tract infection is the most common trigger of asthma exacerbation. Nearly a half of patients with asthma had not been diagnosed with asthma in the early stage. Most asthmatic children use antibiotics and only two-thirds use bronchodilators or inhaled corticosteroid in the treatment. The treatment and management of asthma in children awaits improvement as well.</p>

Effects of triiodothyronine on the learning and memory behaviors in neonatal mice following excitotoxic brain damage / 中国当代儿科杂志

<p><b>OBJECTIVE</b>Some research has shown that learning and memory function impairments in rats with hypothyroidism are associated with triiodothyronine (T3) deficiency in neurons. This study aimed to investigate the effects of L-T3 administration on learning and memory behaviors in neonatal mice with excitotoxic brain damage.</p><p><b>METHODS</b>Seventy-one 5-day-old ICR neonatal mice were randomly assigned to five groups: controls that received intracerebral and intraperitoneal injections of phosphate buffered saline (PBS) (n=14); a group that received intracerebral injections of ibotenic acid (IA) and intraperitoneal injection of PBS (n=14); 3 groups that received intracerebral injections of IA and intraperitoneal injection of L-T3 at 0.2, 0.5, and 1 microg/kg, respectively (n=14-15). Intraperitoneal injections were done 1, 24, 48, 72 and 96 hrs after intracerebral injections. Learning and memory functions were evaluated by the Y-maze discrimination learning test on postnatal days 33-34.</p><p><b>RESULTS</b>The learning and memory functions in the highest L-T3 dose group were significantly better than those in the IA, and the lower L-T3 dose groups, presenting with decreased number of trials to criterion[15.8 + or - 4.5 vs 21.3 + or - 6.3 (IA group), 20.5 + or - 6.0 (0.2 microg/kg L-T3 group) or 21.0 + or - 6.5 (0.5 microg/kg L-T3 group); P<0.05], and achieving a higher correct percentage [91.4+ or - 9.5% vs 79.3 + or - 10.0% (IA group), 77.9 + or - 14.2% (0.2 microg/kg L-T3 group) or 80.7 + or - 12.2% (0.5 microg/kg L-T3 group); P<0.05].</p><p><b>CONCLUSIONS</b>High-dose L-T3 (1 microg/kg) may improve learning and memory functions in mice following excitotoxic brain damage.</p>

Neurobehavioral function of neonatal mice following excitotoxic brain damage / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To assess the changes of neurobehavioral function in a neonatal mouse model of excitotoxic brain damage.</p><p><b>METHODS</b>Fifty-five 5-day-old ICR neonatal mice were randomly assigned to three groups: blank (no intravenous) control (n=20), saline control (n=20) and excitotoxic brain damage model (ibotenic acid treatment, n=15). Behavioral function was evaluated by the surface righting reflex test (postnatal days 6-10), the swimming test (postnatal days 8-12) and the Y-maze discrimination learning test (postnatal days 33-34).</p><p><b>RESULTS</b>Righting time in the surface righting reflex test in the ibotenic acid treatment group on postnatal days 6-10 was more prolonged than that in the two control groups (p<0.05). Swimming test scores in the ibotenic acid treatment group were significantly lower than those in the two control groups (p<0.05). In the Y-maze discrimination learning test, the mice from the ibotenic acid treatment group performed significantly worse than two control groups, presenting with increased learning times (19.79+/-2.42 vs 16.29+/-2.48 or 16.30+/-2.37; p<0.05) and achieving a lower correct percentage (86.7% vs 96.5% or 95.0%) (p<0.05).</p><p><b>CONCLUSIONS</b>The developmental reflexes and learning and memory functions were impaired in neonatal mice following excitotoxic brain damage. Behavioral testing is useful in the evaluation of early developmental reflexes and long-term neurobehavioral outcome in neonatal mice with excitotoxic brain damage.</p>