新生儿出生早期血清降钙素原浓度变化规律及其影响因素分析

目的探讨新生儿出生早期血清降钙素原(PCT)变化规律及常见围产因素对PCT水平的影响。方法分析2012年1月至2014年12月该院收治的无感染健康新生儿470例,其中足月儿240例,早产儿230例,分析其出生一周内血清PCT水平,采用多元线性回归分析胎龄等常见围产因素对PCT水平的影响。结果足月儿及早产儿PCT水平在出生时极低,出生后12h内均略上升,并分别于出生后≥12~24h及≥24~48h达峰值,随后均逐步下降,最后两者分别在出生后约72h后及96h后降至正常婴儿水平。多元回归分析提示早产儿的PCT水平与样本检测时间(出生日龄)及其胎龄大小相关,足月儿PCT水平仅与出生日龄相关。结论足月儿及早产儿在出生早期PCT生理波动规律有所不同,且早产儿胎龄与PCT水平相关,该发现对于新生儿早发细菌感染的诊断与鉴别诊断、指导临床合理使用抗菌药物有重要临床意义。     

Morphine clearance and effects in newborn infants in relation to gestational age

OBJECTIVE: We sought to provide a rational basis for morphine administration in preterm infants in the immediate postnatal period by determining the clearance and evaluating the efficacy and adverse effects of a continuous infusion. STUDY DESIGN: Morphine was infused for 2 to 4 days (140 microg/kg over 1 hour followed by 20 microg/kg/h) to 31 ventilator-treated newborn infants (gestational age, 24 to 41 weeks; birth weight, 765 to 4,015 g). Morphine, morphine-3-glucuronide, and morphine-6-glucuronide concentrations in serum were determined from arterial blood obtained at 2, 12, 24, 48, and 60 hours after the start of morphine infusion at a median postnatal age of 10 hours. RESULTS: The mean +/- SD steady-state morphine concentration, 167 +/- 77 ng/mL, was achieved between 24 and 48 hours of infusion, and morphine-6-glucuronide and morphine-3-glucuronide concentrations did not reach steady state within 60 hours. Morphine clearance (range, 0.8 to 6.5 mL/min/kg) correlated significantly with gestational age (r = 0.60; P < .01) and birth weight (r = 0.55; P < .01). Pain relief did not correlate with the steady-state morphine concentration. However, significantly higher morphine concentrations were found in infants with decreased gastrointestinal motility (187 +/- 82 ng/mL) compared with those without (128 +/- 51 ng/mL; P < .05). CONCLUSIONS: Morphine should be used with caution in prematurely born infants because of its low clearance, which correlates with gestational age.     

Outcomes in gestations between 20 and 25 weeks with preterm premature rupture of membranes

BACKGROUND: Preterm deliveries complicate 11% of all births within the United States. In the urban inner city population, this figure approaches approximately 18%. In one quarter to one third of these deliveries, preterm premature rupture of the membranes (PPROM) has been a causative factor. OBJECTIVE: The purpose of this study was to evaluate outcomes of pregnancies complicated by preterm premature rupture of membranes at less than or equal to 24 weeks gestation at our institution. METHODS: A retrospective review of 300 charts was performed on patients delivered at our institution from December 2003 to December 2004. Patients with gestational ages between 20 and 24 weeks with ruptured membranes were included in the study. Maternal, fetal, placental, and neonatal characteristics were reviewed. RESULTS: A total of 16 infants were delivered. Seven infants were live born. The latency period was 4 days. The mean gestational age was 22 1/7 weeks. The average life span of the live born infants was noted to be 20 days. Chorioamnionitis was demonstrated in 85% of the placental specimens; in 57% of these specimens, group B streptococcus was noted to be the etiologic agent. Of the 16 infants delivered, only one infant is still alive and neurologically intact. CONCLUSION: Various pathogens have been associated with PPROM and subsequent preterm delivery. The findings of this study suggest that within our population, group B streptococcus appears to be the primary causal agent associated with PPROM. Prevention of infection by early surveillance and patient education may help to decrease the incidence, but further investigation is warranted.     

The cost of prematurity: hospital charges at birth and frequency of rehospitalizations and acute care visits over the first year of life: a comparison by gestational age and birth weight

The proportion of preterm and low-birth-weight infants has been growing steadily for two decades. Most of the more than US 10 billion dollars spent on neonatal care in the United States in 2003 was spent on the 12.3% of infants who were born preterm. Research has shown higher initial hospital costs and a higher rate of acute care visits and rehospitalization for preterm and low-birth-weight infants, but only a limited number of studies of the cost of prematurity that follow infants through the first year of life have been conducted. This study is a secondary analysis of data on a subset of infants drawn from a randomized clinical trial that examined health outcomes and health care costs in women with high-risk pregnancies and their infants. For the current study, a sample of 84 singleton infants was chosen. Forty-three infants (51%) were full term (37 weeks' gestation or more) and 41 (49%) were born preterm (less than 37 weeks' gestation). Fifty-five infants (65.5%) were born at normal birth weights (2,500 g or greater), 24 (28.5%) were born at low birth weights (1,501 to 2,499 g), and five (6%) were born at very low birth weights (less than 1,500 g). Data on the initial hospital charges and the rates of rehospitalization and acute care visits in the first year of life in relation to gestational age and birth weight were collected. The results clearly demonstrated that the charges for initial hospitalizations increased as birth weights and gestational ages decreased. Low-birth-weight infants were less likely to have unscheduled acute care visits than normal-birth-weight infants. Interventions to improve prenatal care targeted to women at high risk for delivering preterm or low-birth-weight infants would reduce health care costs and improve health outcomes of infants as well.     

Ultrasonic Backscatter Difference Measurement of Bone Health in Preterm and Term Newborns

Metabolic bone disease of prematurity remains a significant problem for preterm infants. Quantitative ultrasound (QUS) has potential as a non-invasive tool for assessing bone health of newborns. The aim of this study was to assess bone health in preterm and term newborns using ultrasonic backscatter difference measurement. This study analyzed a total of 493 neonates, including 239 full-term infants (gestational age [GA] >37 wk), 201 preterm I infants (GA: 32–37 wk) and 53 extreme preterm II infants (GA <32 wk). Ultrasonic backscatter measurements were performed on the calcaneus of infants at birth, and the normalized mean of the backscatter difference spectrum (nMBD) was calculated as an ultrasonic index of neonatal bone status. Simple and multiple linear regressions were performed to determine the association of ultrasonic nMBD with GA, anthropometric characteristics and biochemical markers. Statistically significant differences in GA, anthropometric characteristics (birth weight, birth length [BL], birth head circumference and body mass index [BMI]) and biochemical markers (alkaline phosphatase, serum calcium and serum phosphate) were observed among preterm and term infants. The nMBD for term infants (median = 3.72 dB/μs, interquartile range [IR] = 1.95 dB/μs) was significantly higher than that for preterm I infants (median = 1.95 dB/μs, IR = 3.12 dB/μs), which was, in turn, significantly higher than that for preterm II infants (median = 0.19 dB/μs, IR = 3.50 dB/μs). The nMBD yielded moderate correlations (ρ = 0.57–0.62, p < 0.001) with GA and anthropometric characteristics and weak correlations (|ρ| = 0.08–0.21, p < 0.001 or not significant) with biochemical markers. Multivariate regressions revealed that only BL (p = 0.002) and BMI (p = 0.032) yielded significantly independent contributions to the nMBD measurement, and combinations of BL and BMI could explain up to 42% of the variation of nMBD in newborn infants. This study found that ultrasonic backscatter difference measurement might be helpful in bone health evaluation in preterm and term newborns. The utility of ultrasonic backscatter measurement in diagnosis of metabolic bone disease in infants should be investigated further.     

早产儿感染血胃泌素和胃动素水平的动态变化

目的探讨早产儿感染对血胃泌素（GAS）和胃动素（MOT）水平的影响。方法用放射免疫法分别测定30例感染早产儿（观察组）和20例无感染早产儿（对照组）入院时、治疗7d后的血GAS、MOT水平。结果（1）观察组早产儿入院时、出院前MOT水平明显低于对照组早产儿（P〈0.05），入院时GAS水平明显高于对照组（P〈0.05），出院前GAS水平与对照组差异无统计学意义。（2）观察组MOT水平变化与危重评分呈正相关；GAS水平变化与危重评分呈负相关。结论早产儿感染影响血GAS、MOT水平，GAS和MOT水平的动态变化可作为早产儿感染、消化状况的指标之一。     

Behavioral responses to pain are heightened after clustered care in preterm infants born between 30 and 32 weeks gestational age

OBJECTIVE: To compare biobehavioral pain responses of preterm infants born at differing gestational ages (GAs) when pain was preceded by a rest period or by a series of routine nursing interventions. METHODS: In a randomized, within subjects, cross-over design, facial (Neonatal Facial Coding System), sleep/wake state and heart rate (HR) responses of 43 preterm infants [mean birth weight: 1303 g (range 590 g to 2345 g); mean GA at birth: 30 weeks (range 25 to 32)] were examined across 3 phases of blood collection (Baseline, Lance, and Recovery) under 2 conditions: pain after a 30-minute rest period versus pain after a series of routine nursing interventions (clustered care). Infant behavioral responses were coded from continuous bedside videotapes. HR was analyzed using custom physiologic signal processing software. RESULTS: Infants born at earlier GA (<30 wk) had equally intense facial responses during the Lance phase regardless of condition. However, later born infants (> or =30 wk GA) showed heightened facial responses indicative of sensitized responses during blood collection when it was preceded by clustered care (P=0.05). Moreover, later born infants had significantly lower facial (P=0.05) and HR (P=0.04) reactivity during Recovery when blood collection followed clustered care. DISCUSSION: Earlier born preterm infants showed heightened states of arousal and poor ability to modulate HR during Recovery when an invasive procedure was preceded by routine tactile nursing procedures. Alternatively, later born infants exhibited sensitized responses when clustered care preceded blood collection. Our findings support the importance of cue based individualized approaches to care.     

The ontogenesis of human fetal hormones. III. Prolactin.

The synthesis and release of human prolactin (hPRL) in the human fetus was assessed by radioimmunoassay analysis of the content and concentration of hPRL in 82 pituitary glands and the concentration of serum hPRL in 47 fetuses of gestational age 68 days to term. Fetal hPRL exhibited parallelism with the reference standard (Lewis 203-1). hPRL was detected by 68 days of gestation (10 wk), the earliest fetal pituitary gland studied; 8 out of 33 pituitaries had a prolactin (PRL) content above 2.0 ng between 10-15 wk gestation. The mean ocntent of PRL in the pituitary gland increased sharply from 14.8 plus or minus 4.6 ng at 15-19 wk to 405 plus or minus 142 ng at 20-24 wk and 542 plus or minus ng at 25-29 wk gestation. By term, the mean content was 2,039 plus or minus 459 (range 493-3,689) and the mean concentration 15.9 plus or minus 2.4 ng/mg (range 7-20). There was a significant positive correlation (P less than 0.001) between the hPRL and human growth hormone (hGH) content of fetal pituitary glands; at term the hPRL/hGH ratio was 1/290. The concentration of serum hPRL between 12 and 24 wk ranged from 2.9 to 67 ng/ml, mean 19.5 plus or minus 2.5 ng/ml )n = 21); by 26 wk fetal serum hPRL increased sharply and attained levels of 300-500 ng/ml in late gestation. At delivery, the mean plasma concentration of hPRL was 167 plus or minus 14.2 ng/ml in 36 umbilical venous specimens and 111.8 plus or minus 12.3 ng/ml in the matched maternal venous specimens. No correlation between serum hPRL and the pituitary content or concentration of hPRL was demonstrable in 12 matched fetal specimens. In five anencephalic infants, umbilical venous hPRL levels were between 65 and 283 ng/ml. In two anencephalic infants, thyrotropin releasing factor (TRF) (200 mug IV) evoked a rise in serum hPRL in one patient from 43 to 156 ng/ml at 30 min, and in the other from 65 to 404 ng/ml at 120 min. In both patients, plasma thyroid-stimulating hormone (TSH) rose from undetectable base-line levels to peak levels of 97 and 380 muU/ml, respectively. The pattern of change in serum hPRL in the human fetus contrasts sharply with that of serum hGH, luteinizing hormone, or follicle-stimulating hormone. These observations in the fetus and in anencephalic infants suggest that the striking elevation of serum PRL in the fetus is neither mediated by a putative PRL releasing factor or by TRF, nor is a consequence of suppression or absence of PRL release inhibiting factor alone, as a functional hypothalamus is not required to attain the high PRL concentration at term. Several lines of evidence support the view that high plasma estrogen levels characteristic of gestation act directly on the fetal anterior hypophysis to stimulate PRL secretion or to sensitize the secretory mechanism of the lactotrope, increasing its responsiveness to other stimuli.     

血清表皮生长因子与早产儿肺发育相关研究

目的 探讨血清表皮生长因子水平与早产儿肺发育的相关性.方法 选择住院早产儿35例.根据胎龄分成3组,分别是①28周≤胎龄〈32周,9例,②32周≤胎龄〈35周,14例,③35周≤胎龄〈37周,12例,同时根据有无并发早产儿肺透明膜病（HMD）分为HMD组19例,非HMD组16例;对照组选择足月儿高胆红素血症住院患儿12例.无其他并发症.采用酶联免疫吸附测定法（ELISA）,35例早产儿和12例对照组足月儿分别于出生1h、24h、72h、和生后第7天空腹股静脉采血测定血清表皮生长因子水平.结果 早产儿组出生1h、24h、72h、和生后第7天.血清表皮生长因子含量水平均呈递增关系,差异有显著性;早产儿组与足月儿组血清表皮生长因子含量水平于出生1h、24h、72h差异有显著性,生后第7天差异无显著性;在生后1h、24h、72h,早产儿有HMD组与无HMD组患儿血清表皮生长因子含量水平差异有显著性.结论 早产儿出生后血清表皮生长因子含量水平呈递增关系,提示早产儿出生后体内EGF合成和释放增加,可能促进肺脏器成熟;早产儿组与足月儿组血清表皮生长因子含量水平出生后差异有显著性,早产儿出生后血清EGF浓度水平和HMD的严重程度正相关,提示在新生儿早期检测血清表皮生长因子含量可以作为HMD发病的预测指标.     

Prevalence of gestational diabetes and macrosomic newborns in a Mexican population

Prevalence of gestational diabetes was investigated in 693 pregnant patients between the 24th and 28th wk of gestation. A glucose screening test (GST) was performed with a 50-g glucose load, followed by a blood sample 1 h later. Patients with glucose levels greater than 140 mg/dl 1 h after the GST were scheduled for a full oral glucose tolerance test (OGTT). One hundred seven patients had an abnormal GST, and 30 patients (4.3%) were diagnosed as having gestational diabetes mellitus (GDM). The percentage of GDM increased significantly when glucose levels were greater than 180 mg/dl to a maximum of 84.61% when glucose levels were greater than 200 mg/dl. Also, patient age was directly related to GDM, which increased in incidence to 20% when patients greater than 26 yr had an abnormal GST. After delivery, newborn weights were compared between those born to mothers with GDM (n = 30) and those born to mothers with an abnormal GST (n = 77). Patients with an abnormal GST and normal OGTT had 12 (15.58%) macrosomic and 2 premature newborns. However, patients with GDM had 5 (16.66%) macrosomic and no premature newborns. Patients with a normal GST had 7.33% of the macrosomic newborns. There was no perinatal mortality in newborns of GDM mothers; only 1 of the 5 macrosomic newborns presented transient hypoglycemia. Evaluation of 26 GDM patients was possible after delivery, disclosing 3 (11.53%) with non-insulin-dependent diabetes mellitus and 5 (19.23%) with impaired glucose tolerance. These results showed 4.3% undetected GDM in our population and no differences in the proportion of macrosomic newborns between those born to mothers with GDM and those born to mothers with an abnormal GST.     

Mortality and morbidity in extremely preterm infants (22 to 26 weeks of gestation): Austria 1999–2001

OBJECTIVE: The aim of this retrospective study was to analyze the mortality and morbidity for extremely preterm infants with a gestational age from 22 to 26 weeks. All infants were born in Austria during the years 1999-2001. METHODS: Data were collected from 16 neonatal intensive care units in Austria. Main outcome criteria were mortality, the rates of chronic lung disease (CLD) and severe retinopathy of prematurity (ROP, stage > or =3) to determine the short-term outcome; the rate of cerebral palsy (CP) at the corrected age of twelve months to assess the long-term outcome. RESULTS: Overall, 796 preterm infants with a gestational age less than 27 weeks were born in Austria and 581 (73%) were registered as live-born infants. Of those live born, 508 (87%) were analyzed. The mortality rates were 83%, 76%, 43%, 26% and 13% for 22, 23, 24, 25 and 26 weeks' gestation, respectively. The rates of CLD were 33% (22 weeks), 36% (23 weeks), 42% (24 weeks), 31% (25 weeks) and 22% (26 weeks). The rates of ROP of stage > or =3 were 0% (22 weeks), 29% (23 weeks), 23% (24 weeks), 18% (25 weeks) and 10% (26 weeks). The rates of CP at the corrected age of 12 months were 33%, 50%, 33%, 26% and 25% for 22, 23, 24, 25 and 26 weeks' gestation, respectively. CONCLUSIONS: The results of this national study are in accordance with the international literature: mortality and morbidity increased with decreasing gestational age.     

Pharmacokinetics and metabolism of intravenous midazolam in preterm infants.

BACKGROUND: Midazolam, a benzodiazepine, is finding expanded use in neonatal intensive care units. We studied the pharmacokinetics and metabolism of midazolam after a single intravenous dose in preterm infants. METHODS: The pharmacokinetics of midazolam and its hydroxylated metabolite (1-OH-midazolam) after a single 0.1 mg/kg intravenous dose of midazolam were determined in 24 preterm infants (gestational age, 26 to 34 weeks; postnatal age, 3 to 11 days). Blood samples were obtained before drug administration and at 0.5, 1, 2, 4, 6, 12, and 24 hours after the start of the infusion. Midazolam and 1-OH-midazolam concentrations were determined by use of gas chromatography-mass spectrometry. RESULTS: Total body clearance, apparent volume of distribution, and plasma half-life of midazolam were (median [range]): 1.8 (0.7-6.7) ml/kg per min, 1.1 (0.4-4.2) L/kg, and 6.3 (2.6-17.7) h, respectively. In 19 of 24 preterm infants, 1-OH-midazolam concentrations could be detected: 1-OH-midazolam (1-OH-M) maximal concentration of drug in plasma (C(max)), time to reach C(max) (T(max)), and 1-OH-M/M area under the concentration-time curve from time zero to the last sampling time point (AUC(0-t)) ratio were [median (range)]: 8.2 (<0.5-68.2) ng/ml, 6 (1-12) h, and 0.09 (<0.001-1), respectively. Midazolam plasma clearance was increased in those infants who had indomethacin (INN, indometacin) exposure. DISCUSSION: Consequent to immature hepatic cytochrome P450 3A4 (CYP3A4) activity, midazolam clearance and 1-OH-midazolam concentrations are reduced markedly in preterm infants as compared to concentrations in previous reports from studies in older children and adults. Indomethacin exposure and its apparent impact on midazolam clearance support alteration of drug disposition produced by a patent ductus arteriosus or by the direct effects of indomethacin on hemodynamic or renal function.     

High-dose ibuprofen for patent ductus arteriosus in extremely preterm infants: a randomized controlled study

Our aim was to assess the hypothesis that a high-dose regimen of ibuprofen is more effective than the standard-dose regimen in closing patent ductus arteriosus (PDA) without increasing adverse effects. Infants of gestational age <29 weeks, with respiratory distress syndrome (RDS) and echocardiographic evidence of significant PDA at 12-24 h of life, were randomized to receive a standard (10-5-5 mg/kg/day) or high-dose (20-10-10 mg/kg/day) course of ibuprofen. We studied 70 infants, 35 of whom received the standard dose of ibuprofen and the other 35 the high dose. Of the infants treated with the standard-dose regimen, 37% had persistent PDA as compared with 14% of those treated with the high-dose regimen (P = 0.03). No differences in the occurrence of adverse effects were observed between the two groups. The high-dose ibuprofen regimen is more effective than the standard-dose regimen in closing PDA in preterm infants <29 weeks of gestation without increasing the adverse effect rate.     

The Ontogenesis of Human Fetal Hormones: I. GROWTH HORMONE AND INSULIN

The content and concentration of immunoreactive growth hormone (GH) were measured in 117 human fetal pituitary glands from 68 days of gestation to term and in the pituitary glands of 20 children 1 month to 9 yr of age. Physicochemical and immunochemical properties of GH of fetal pituitary glands and GH from adult pituitary glands were indistinguishable by disc gel electrophoresis, immunoelectrophoresis, starch gel electrophoresis, and radioimmunoassay techniques. In the fetal pituitary gland, the GH content rose from mean levels of 0.44+/-0.2 mug at 10-14 wk of gestation, to 9.21+/-2.31 mug at 15-19 wk, to 59.38+/-11.08 mug at 20-24 wk, to 225.93+/-40.49 mug at 25-29 wk, to 577.67+/-90 mug at 30-34 wk, and to 675.17+/-112.33 mug at 35-40 wk. There was a significant positive correlation between growth hormone content of the pituitary and gestational age, crown-rump length, and the weight of the pituitary gland.The content and concentration (micrograms/milligram) of human growth hormone (HGH) in the fetal pituitary showed significant increments (P < 0.001) for each 4 wk period of gestation until 35 wk. Further increases in the HGH content were noted in pituitaries of children aged 1-9 yr (range of 832 to 11.211 mug).Immunoreactive GH was detected in fetal serum at a concentration of 14.5 ng/ml as early as 70 days gestation, the youngest fetus assayed. At 10-14 wk, the mean concentration of serum growth hormone was 65.2+/-7.6 ng/ml; at 15-19 wk 114.9+/-12.5 ng/ml; at 20-24 wk 119.3+/-19.8 ng/ml; at 25-29 wk 72.0+/-11.5 ng/ml; and 33.5+/-4.2 ng/ml at term. A significant negative correlation of serum growth hormone with advancing gestational age after 20-24 wk was observed (P < 0.001). In 17 fetuses paired serum and pituitary samples were assayed; no significant correlation between the concentration of serum GH and the pituitary content or concentration of GH was demonstrable.The serum concentration of chorionic somatomammotropin (HCS) in the fetus was unrelated to gestational age. Insulin (1-30 muU/ml) was detected in 42 of 46 fetal sera assayed.These data suggest that the appearance and development of the secretory capacity for GH by the human fetal pituitary gland coincides with developmental changes in the portal system and hypothalamus. Maturation of inhibitory central nervous system control mechanisms for secretion of GH may not occur until infancy.     

小于胎龄儿出生后血清维生素B12及脑发育水平研究

目的检测小于胎龄儿、适于胎龄儿出生后血清维生素B12(VB12)、同型半胱氨酸(Hcy)水平的差异并对足月儿进行行为神经评定,探讨VB12、Hcy对胎儿发育的影响及小于胎龄儿脑发育水平。方法根据胎龄与出生体质量的关系,将符合入选条件的研究对象分为小于胎龄儿组(早产小于胎龄儿亚组、足月小于胎龄儿亚组)、适于胎龄儿组(早产适于胎龄儿亚组、足月适于胎龄儿亚组),检测其血清中VB12、Hcy水平,分析出生时血清VB12、Hcy水平与出生体质量、胎龄的关系,比较小于胎龄儿、适于胎龄儿组出生时血清VB12、Hcy的水平差异。采用新生儿20项行为神经评定法(NBNA)对生后2~3 d的足月小于胎龄儿亚组、足月适于胎龄儿亚组进行行为神经测定并比较2组差别。结果出生时血清VB12水平与出生体质量呈正相关(r=0.564,P<0.05);血清Hcy水平与出生体质量呈负相关(r=-0.569,P<0.05)。早产适于胎龄儿亚组出生时血清VB12水平高于、Hcy水平低于早产小于胎龄儿亚组[VB12:(262.07±62.25)pg/ml vs(228.21±67.27)pg/ml;Hcy:(8.47±3.81)μmol/L vs(17.53±10.56)μmol/L],差异有统计学意义(P均<0.05);足月适于胎龄儿亚组出生时血清VB12水平高于、Hcy水平低于足月小于胎龄儿亚组[VB12:(431.03±113.82)pg/ml vs(254.80±72.35)pg/ml;Hcy:(4.61±2.88)μmol/L vs(13.60±9.29)μmol/L],差异有统计学意义(P均<0.05)。与足月适于胎龄儿亚组相比,足月小于胎龄儿亚组NBNA总分、行为能力、被动肌张力、主动肌张力评分均明显降低(P均<0.05)。结论出生时血清VB12水平与出生体质量、胎龄呈正相关;血清Hcy水平与出生体质量、胎龄呈负相关;小于胎龄儿出生时血清VB12水平较适于胎龄儿低,Hcy水平较适于胎龄儿高,提示VB12可能影响胎儿生长发育。足月小于胎龄儿早期NBNA评分较足月适于胎龄儿明显减低,说明小于胎龄儿出生时行为神经能力已受到影响。     

Ghrelin, leptin, IGF-1, IGFBP-3, and insulin concentrations at birth: is there a relationship with fetal growth and neonatal anthropometry?

BACKGROUND: Insulin, growth hormone (GH), and growth factors (insulin-like growth factors [IGFs] and their binding proteins [IGFBPs]) are known to influence fetal growth and also the synthesis/secretion of the recently discovered hormones leptin and ghrelin. METHODS: In 153 delivering mothers and their offspring at birth, we prospectively investigated the association between mothers' and babies' serum concentrations of ghrelin, leptin, insulin, IGF-1, and IGFBP-3 and neonatal anthropometric characteristics and the growth of the fetus. We also tried to put babies' serum glucose and GH measurements in this context. RESULTS: Birth weight (BW), birth length, head circumference, and ponderal index (PI) were positively associated with cord IGF-1, IGFBP-3, and leptin and negatively associated with GH. BW was independently associated with maternal stature and prepartum weight, birth length with maternal stature, PI with maternal insulin and prepartum weight, and head circumference with maternal ghrelin. Compared with preterm infants whose development was appropriate for gestational age (AGA), preterm growth-restricted babies displayed alteration in GH-IGF axis (increased GH and low IGF-1 and IGFBP-3 concentrations), low leptin and glucose concentrations, and increased ghrelin concentrations. In large-for-gestational-age (LGA) babies, leptin, IGFBP-3, insulin, and glucose concentrations were significantly higher in asymmetric LGA newborns than in symmetric LGA and AGA newborns. CONCLUSIONS: We found relationships between metabolic factors, fetal growth, and anthropometry. Intrauterine growth restriction involved alteration in the fetal GH-IGF axis, with relatively low leptin and glucose concentrations and increased ghrelin concentrations. Leptin, insulin, and IGFBP-3 delineated subtypes of fetal overgrowth.     

Postnatal Fetal and Adult Hemoglobin Synthesis in Early Preterm Newborn Infants

Studies were carried out during the postnatal period in infants born at or before the 32nd wk of gestation to determine the proportion of fetal hemoglobin (Hb F) and adult hemoglobin (Hb A) being synthesized, and to compare these studies to those previously reported on at birth from normal newborn infants 25-43 wk gestation. When the pretern infants reached the postconceptional age corresponding to term, their Hb A and Hb F synthesis was compared to a group of newborn infants at term. 53 blood samples from 25 preterm and 11 full-term infants were incubated in an amino acid mixture containing [(14)C]leucine, and column-chromatographed on DEAE-Sephadex for separation of Hb F and Hb A fractions. The completeness of the DEAE-Sephadex separation of Hb F and Hb A was confirmed by globin chain chromatography with the use of carboxymethylcellulose. The rate of transition from Hb F to Hb A synthesis postnatally in the preterm infants resembled that reflecting the in utero transition. At the postconceptional age corresponding to term, there was no difference in the relative amounts of Hb F and Hb A being synthesized by the preterm infants and by the term infants. The birth process did not alter the rate of transition from Hb F to Hb A.     

超声评价新生儿胼胝体发育及影响因素

目的通过颅脑超声监测胼胝体的生长率,分析新生儿胼胝体发育的影响因素,为早期评价和治疗脑发育性疾病提供依据。 方法选择2016年4月至12月就诊于兰州大学第二医院新生儿重症监护室（NICU）的97例新生儿,其中,早产儿54例（27~34周）,足月儿43例。所有新生儿于出生后0~6周每周行颅脑超声检查并测量胼胝体矢状长度,通过独立样本t检验比较早产儿、足月儿出生后0~6周胼胝体生长率。采用Spearman相关分析孕周、新生儿出生体质量与胼胝体生长率之间的关系。 结果（1）新生儿出生时胼胝体矢状长度与孕周、出生体质量成正相关（r=0.57、0.58）;（2）早产儿出生后0周、2周、3周、4周、5周、6周胼胝体长度均低于足月儿,差异均有统计学意义（t=6.22、6.51、7.81、8.87、10.25、11.64,P均<0.001）;（3）早产儿、足月儿出生后0~2周胼胝体生长率比较,差异无统计学意义（P>0.05）,出生后2~6周每周早产儿胼胝体生长率均低于足月儿,差异均有统计学意义（t=13.91、14.76、13.85、12.21,P均<0.001）。 结论新生儿胼胝体的发育与孕周、出生体质量有关;颅脑超声能实时动态监测胼胝体的生长发育。     

High urinary concentrations of activin A in asphyxiated full-term newborns with moderate or severe hypoxic ischemic encephalopathy

BACKGROUND: Hypoxic ischemic encephalopathy (HIE) is a major cause of permanent neurological disabilities in full-term newborns. We measured activin A in urine collected immediately after birth in asphyxiated full-term newborns, and assessed the ability of the measurements to predict the occurrence of perinatal encephalopathy. METHODS: We studied 30 infants with perinatal asphyxia and 30 healthy term neonates at the same gestational age. We recorded routine laboratory variables, cranial assessments by standard cerebral ultrasound, and the presence or absence of neurological abnormalities during the first 7 days after birth. Urinary activin A concentrations were measured at first urination and 12, 24, 48, and 72 h after birth. RESULTS: Asphyxiated infants were subdivided as follows: group A (n = 18): no or mild HIE with good prognosis and group B (n = 12): moderate or severe HIE with a greater risk of neurological handicap. Activin A concentrations in urine collected at birth (median collection time at first urination <2 h) and at 12, 24, 48, and 72 h from birth were significantly (P <0.0001) higher in asphyxiated newborns with moderate or severe HIE (Group B) than in those with absent of mild HIE (group A) and controls. Concentrations did not differ between group A and controls. Activin A concentrations were >0.08 mug/L at first urination in 10 of 12 patients with moderate or severe HIE but in none of 18 patients with no or mild HIE. CONCLUSIONS: Activin A measurements in urine soon after birth may be a promising tool to identify which asphyxiated infants are at risk of neurological sequelae.     

Umbilical cord and maternal blood leptin concentrations in intrauterine growth retardation.

Leptin, the ob gene product, plays an important role in the regulation of body fat mass and weight. In previous studies, it was demonstrated that leptin is detectable in human fetal cord blood as early as at 18 weeks of gestation and that serum leptin concentrations are significantly reduced in small gestational age newborns. In the present study, we investigated whether umbilical and maternal serum leptin concentrations correlate with intrauterine growth retardation (IUGR). In addition, we aimed to determine the relationships between leptin concentration in the maternal and cord blood. We studied 40 newborn infants (21 female and 19 male; gestational age, 38-42 weeks) and their mothers. Of the infants studied, 10 had IUGR. Serum leptin concentrations were measured by radioimmunoassay. All newborns had detectable leptin concentrations. Leptin concentrations were significantly lower in newborns with IUGR and in their mothers (n = 10; 3.53 +/- 1.42 ng/ml, 6.75 +/- 1.47 ng/ml, respectively) than in infants experiencing normal growth and their mothers (n = 30; 5.58 +/- 2.98 ng/ml, 9.85 +/- 6.50 ng/ml, respectively) (p < 0.01 for newborns, p < 0.05 for mothers). There was no significant correlation between umbilical leptin concentration and maternal leptin concentration (r = 0.229; p = 0.155) in all study groups but, significantly, a correlation was observed in the group with IUGR (r = 0.736; p = 0.015). There were no significant correlations between both umbilical and maternal leptin concentrations and parity, delivery type and gestational age. There was a correlation between umbilical leptin concentration and birth weight of newborns (r = 0.383; p = 0.015) but no correlation with body mass index (BMI) of the newborns (r = 0.034; p = 0.834). Maternal leptin concentrations correlated with maternal weight and BMI (r=0.606; p=0.000, r=0.535; p=0.000, respectively). There was no correlation between maternal leptin concentrations and birth weight of the newborns (r=0.179; p=0.269) and with BMI of the newborns (r = 0.146; p = 0.367). There was no gender difference in leptin concentrations in the newborns (n=21; 5.50 +/- 3.37 ng/ml, for females; n = 19; 4.58 +/- 1.98 ng/ml for males) (p = 0.296). In summary, we have shown that IUGR is associated with a decreased leptin concentration in newborns and their mothers. The association between umbilical serum leptin and birth weight in this and other studies suggests a pivotal role of fetal leptin in regulating fetal growth and development.