Lesion environments direct transplanted neural progenitors towards a wound repair astroglial phenotype in mice.

Neural progenitor cells (NPC) represent potential cell transplantation therapies for CNS injuries. To understand how lesion environments influence transplanted NPC fate in vivo, we derived NPC expressing a ribosomal protein-hemagglutinin tag (RiboTag) for transcriptional profiling of transplanted NPC. Here, we show that NPC grafted into uninjured mouse CNS generate cells that are transcriptionally similar to healthy astrocytes and oligodendrocyte lineages. In striking contrast, NPC transplanted into subacute CNS lesions after stroke or spinal cord injury in mice generate cells that share transcriptional, morphological and functional features with newly proliferated host astroglia that restrict inflammation and fibrosis and isolate lesions from adjacent viable neural tissue. Our findings reveal overlapping differentiation potentials of grafted NPC and proliferating host astrocytes; and show that in the absence of other interventions, non-cell autonomous cues in subacute CNS lesions direct the differentiation of grafted NPC towards a naturally occurring wound repair astroglial phenotype.

Prenatal tobacco smoke exposure and neurological impairment at 10 years of age among children born extremely preterm: a prospective cohort.

OBJECTIVE: To determine the association between prenatal tobacco smoke exposure and neurological impairment at 10 years of age among children born extremely preterm (<28 weeks of gestation). DESIGN: The Extremely Low Gestational Age Newborn (ELGAN) Study, a prospective cohort. SETTING: Ten-year follow-up of extremely preterm infants born at 14 US hospitals between 2002 and 2004. METHODS: Prenatal tobacco smoke exposure was defined as a mother's report at enrolment of active (i.e. maternal) and passive smoking during pregnancy. Poisson regression with generalized estimating equations was used. Models adjusted for mother's age, race/ethnicity, education, insurance, pre-pregnancy body mass index, US region, multiple gestation and infant's sex; and in sensitivity analysis, gestational age at delivery and clinical subtype of preterm birth, given their classification as intermediate and non-confounding variables. MAIN OUTCOMES: Neurological impairment at 10 years, epilepsy, cerebral palsy and cognitive impairment. RESULTS: Of 1200 ELGAN study survivors, 856 were assessed at 10 years of age with neurological outcomes, of whom 14% (118/856) had active tobacco exposure during pregnancy and 24% (207/852) had passive tobacco exposure. Compared with children who were not exposed prenatally to tobacco, children exposed to active tobacco use during pregnancy had a higher risk of epilepsy (14% versus 5%; adjusted relative risk: 1.68, 95% CI 1.45-1.92). This risk remained after adjustment for gestational age at delivery and clinical subtype of preterm birth. Prenatal tobacco smoke exposure was not associated with other assessed neurological outcomes, including cerebral palsy and multiple measures of cognitive impairment. CONCLUSIONS: Among children born extremely preterm, prenatal active tobacco smoke exposure was associated with an increased risk of epilepsy at 10 years of life. TWEETABLE ABSTRACT: Among infants born before 28 weeks of gestation, prenatal active tobacco smoke exposure was associated with an increased risk of epilepsy at 10 years of life.

Injectable polypeptide hydrogels via methionine modification for neural stem cell delivery.

Injectable hydrogels with tunable physiochemical and biological properties are potential tools for improving neural stem/progenitor cell (NSPC) transplantation to treat central nervous system (CNS) injury and disease. Here, we developed injectable diblock copolypeptide hydrogels (DCH) for NSPC transplantation that contain hydrophilic segments of modified l-methionine (Met). Multiple Met-based DCH were fabricated by post-polymerization modification of Met to various functional derivatives, and incorporation of different amino acid comonomers into hydrophilic segments. Met-based DCH assembled into self-healing hydrogels with concentration and composition dependent mechanical properties. Mechanical properties of non-ionic Met-sulfoxide formulations (DCHMO) were stable across diverse aqueous media while cationic formulations showed salt ion dependent stiffness reduction. Murine NSPC survival in DCHMO was equivalent to that of standard culture conditions, and sulfoxide functionality imparted cell non-fouling character. Within serum rich environments in vitro, DCHMO was superior at preserving NSPC stemness and multipotency compared to cell adhesive materials. NSPC in DCHMO injected into uninjured forebrain remained local and, after 4 weeks, exhibited an immature astroglial phenotype that integrated with host neural tissue and acted as cellular substrates that supported growth of host-derived axons. These findings demonstrate that Met-based DCH are suitable vehicles for further study of NSPC transplantation in CNS injury and disease models.

Early postnatal illness severity scores predict neurodevelopmental impairments at 10 years of age in children born extremely preterm.

OBJECTIVE: A neonatal illness severity score, The Score for Neonatal Acute Physiology-II (SNAP-II), predicts neurodevelopmental impairments at two years of age among children born extremely preterm. We sought to evaluate to what extent SNAP-II is predictive of cognitive and other neurodevelopmental impairments at 10 years of age. STUDY DESIGN: In a cohort of 874 children born before 28 weeks of gestation, we prospectively collected clinical, physiologic and laboratory data to calculate SNAP-II for each infant. When the children were 10 years old, examiners who were unaware of the child's medical history assessed neurodevelopmental outcomes, including neurocognitive, gross motor, social and communication functions, diagnosis and treatment of seizures or attention deficit hyperactivity disorder (ADHD), academic achievement, and quality of life. We used logistic regression to adjust for potential confounders. RESULTS: An undesirably high SNAP-II (⩾30), present in 23% of participants, was associated with an increased risk of cognitive impairment (IQ, executive function, language ability), adverse neurological outcomes (epilepsy, impaired gross motor function), behavioral abnormalities (attention deficit disorder and hyperactivity), social dysfunction (autistic spectrum disorder) and education-related adversities (school achievement and need for educational supports. In analyses that adjusted for potential confounders, Z-scores ⩽-1 on 11 of 18 cognitive outcomes were associated with SNAP-II in the highest category, and 6 of 18 were associated with SNAP-II in the intermediate category. Odds ratios and 95% confidence intervals ranged from 1.4 (1.01, 2.1) to 2.1 (1.4, 3.1). Similarly, 2 of the 8 social dysfunctions were associated with SNAP-II in the highest category, and 3 of 8 were associated with SNAP-II in the intermediate category. Odds ratios and 95% confidence intervals were slightly higher for these assessments, ranging from 1.6 (1.1, 2.4) to 2.3 (1.2, 4.6). CONCLUSION: Among very preterm newborns, physiologic derangements present in the first 12 postnatal hours are associated with dysfunctions in several neurodevelopmental domains at 10 years of age. We are unable to make inferences about causality.

Volume guarantee pressure support ventilation in extremely preterm infants and neurodevelopmental outcome at 18 months.

OBJECTIVE: Compared with pressure-controlled ventilation (PCV), volume-targeted ventilation is associated with decreased neonatal complications, including the combined outcome of death or bronchopulmonary dysplasia. However, little is known about its effect on neurodevelopmental outcome. We evaluated the hypothesis that as compared with PCV, volume-targeted ventilation reduces the risk of the combined outcome of neurodevelopmental impairment or death in very low birth weight infants. STUDY DESIGN: We studied a cohort of extremely preterm infants managed with either volume guarantee pressure support ventilation (VGPSV; n=135) or PCV (n=135). Infants were evaluated at 18 months adjusted age with a standardized neurological examination and the Bayley Scales of Infant and Toddler Development-third edition. Logistic regression models were used to evaluate the association of ventilation mode and neurodevelopmental outcome. RESULT: Rates of pulmonary interstitial emphysema (odds ratio 0.6; 95% confidence limits: 0.4, 0.8), hypotension (odds ratio: 0.7; 95% confidence limits: 0.5, 0.9) and mortality (odds ratio 0.45; 95% confidence limits: 0.22, 0.9) were lower among infants treated with VGPSV. The infants in the VGPSV group had a significantly shorter duration on mechanical ventilation compared with infants in the PCV group (log-rank test P<0.01). Seventy percent (155/221) of survivors were evaluated at 18 months adjusted age. A trend towards benefit for the combined outcome of death or neurodevelopmental impairment was seen in the VGPSV group but did not reach statistical significance (odds ratio: 0.59; 95% confidence limits: 0.32, 1.08). CONCLUSION: VGPSV was associated with a decreased risk of short-term complications but not long-term developmental impairment in this modest-sized cohort.

Brain wave maturation and neurodevelopmental outcome in extremely low gestational age neonates.

OBJECTIVE: Infants born at extremely low gestational ages are at high risk for developmental impairments. Early predictors of these impairments are useful for both clinicians and researchers. Our objective was to assess the correlation between the rate of brain wave maturation as measured by serial amplitude-integrated electroencephalograms (aEEGs) and scores on standardized measures of infant development in extremely low gestational age neonates. STUDY DESIGN: This was a prospective observational study of 65 infants born before 28 weeks' gestational age who were assessed with an aEEG monthly between 28 and 36 weeks' postmenstrual age and with the Bayley Scales of Infant and Toddler Development-III at 18 to 22 months adjusted age. We analyzed the correlation between the rate of brain wave maturation on aEEG and Bayley Scales of Infant and Toddler Development-III Cognitive and Motor Scales. RESULT: The mean rate of brain wave maturation was 0.83 (±0.36) points per week. Brain wave maturation was not correlated with either the Cognitive or Motor Scale (adjusted regression coefficients for Cognitive and Motor Scales were 1.61 (s.e.: 4.20; P=0.70) and 2.39 (s.e.: 4.62; P=0.61), respectively. CONCLUSION: Among extremely preterm infants, the rate of maturational changes in brain wave characteristics between 28 and 36 weeks' postmenstrual age is not predictive of developmental abilities at 18 to 22 months adjusted age.

Antenatal steroid exposure and pulmonary outcomes in adolescents born with very low birth weight.

OBJECTIVE: To compare asthma history and pulmonary function in adolescents born prematurely with very low birth weight with and without antenatal steroid exposure. STUDY DESIGN: We studied 188 fourteen-year olds (94 exposed, 84 male). We used parent report to ascertain asthma and asthma-related symptoms and spirometry to assess pulmonary function. Steroid-exposed and -unexposed groups were compared using Mann-Whitney U-tests (continuous variables), χ(2) analysis (categorical variables) and logistic regression (multivariate analyses). RESULT: The steroid-exposed group had greater prevalence of larger airway obstruction (35% vs 21%), and steroid-exposed adolescents with birth weights <1000 g had 4.5-fold higher odds of larger airway obstruction. Wheezing in the past 12 months was two times as prevalent in steroid-exposed adolescents with birth weights between 1000 and 1500 g. CONCLUSION: Antenatal steroid exposure does not provide long-term benefits for pulmonary outcomes in adolescents born prematurely with very low birth weight in the era of surfactant therapy.

Efficacy of phototherapy devices and outcomes among extremely low birth weight infants: multi-center observational study.

OBJECTIVE: Evaluate the efficacy of phototherapy (PT) devices and the outcomes of extremely premature infants treated with those devices. STUDY DESIGN: This substudy of the National Institute of Child Health and Human Development Neonatal Research Network PT trial included 1404 infants treated with a single type of PT device during the first 24±12 h of treatment. The absolute (primary outcome) and relative decrease in total serum bilirubin (TSB) and other measures were evaluated. For infants treated with one PT type during the 2-week intervention period (n=1223), adjusted outcomes at discharge and 18 to 22 months corrected age were determined. RESULT: In the first 24 h, the adjusted absolute (mean (±s.d.)) and relative (%) decrease in TSB (mg dl(-1)) were: light-emitting diodes (LEDs) -2.2 (±3), -22%; Spotlights -1.7 (±2), -19%; Banks -1.3 (±3), -8%; Blankets -0.8 (±3), -1%; (P<0.0002). Some findings at 18 to 22 months differed between groups. CONCLUSION: LEDs achieved the greatest initial absolute reduction in TSB but were similar to Spots in the other performance measures. Long-term effects of PT devices in extremely premature infants deserve rigorous evaluation.

Motor cortical functional geometry in cerebral palsy and its relationship to disability.

OBJECTIVE: To investigate motor cortical map patterns in children with diplegic and hemiplegic cerebral palsy (CP), and the relationships between motor cortical geometry and motor function in CP. METHODS: Transcranial magnetic stimulation (TMS) was used to map motor cortical representations of the first dorsal interosseus (FDI) and tibialis anterior (TA) muscles in 13 children with CP (age 9-16 years, 6 males.) The Gross Motor Function Measure (GMFM) and Melbourne upper extremity function were used to quantify motor ability. RESULTS: In the hemiplegic participants (N = 7), the affected (right) FDI cortical representation was mapped on the ipsilateral (N = 4), contralateral (N = 2), or bilateral (N = 1) cortex. Participants with diplegia (N = 6) showed either bilateral (N = 2) or contralateral (N = 4) cortical hand maps. The FDI and TA motor map center-of-gravity mediolateral location ranged from 2-8 cm and 3-6 cm from the midline, respectively. Among diplegics, more lateral FDI representation locations were associated with lower Melbourne scores, i.e. worse hand motor function (Spearman's rho = -0.841, p = 0.036). CONCLUSIONS: Abnormalities in TMS-derived motor maps cut across the clinical classifications of hemiplegic and diplegic CP. The lateralization of the upper and lower extremity motor representation demonstrates reorganization after insults to the affected hemispheres of both diplegic and hemiplegic children. SIGNIFICANCE: The current study is a step towards defining the relationship between changes in motor maps and functional impairments in CP. These results suggest the need for further work to develop improved classification schemes that integrate clinical, radiologic, and neurophysiologic measures in CP.

Early postnatal hypotension is not associated with indicators of white matter damage or cerebral palsy in extremely low gestational age newborns.

OBJECTIVE: To evaluate, in extremely low gestational age newborns (ELGANs), relationships between indicators of early postnatal hypotension and cranial ultrasound indicators of cerebral white matter damage imaged in the nursery and cerebral palsy diagnoses at 24 months follow-up. STUDY DESIGN: The 1041 infants in this prospective study were born at <28 weeks gestation, were assessed for three indicators of hypotension in the first 24 postnatal hours, had at least one set of protocol cranial ultrasound scans and were evaluated with a structured neurological exam at 24 months corrected age. Indicators of hypotension included: (1) lowest mean arterial pressure (MAP) in the lowest quartile for gestational age; (2) treatment with a vasopressor; and (3) blood pressure lability, defined as the upper quartile of the difference between each infant's lowest and highest MAP. Outcomes included indicators of cerebral white matter damage, that is, moderate/severe ventriculomegaly or an echolucent lesion on cranial ultrasound and cerebral palsy diagnoses at 24 months gestation. Logistic regression was used to evaluate relationships among hypotension indicators and outcomes, adjusting for potential confounders. RESULT: Twenty-one percent of surviving infants had a lowest blood pressure in the lowest quartile for gestational age, 24% were treated with vasopressors and 24% had labile blood pressure. Among infants with these hypotension indicators, 10% percent developed ventriculomegaly and 7% developed an echolucent lesion. At 24 months follow-up, 6% had developed quadriparesis, 4% diparesis and 2% hemiparesis. After adjusting for confounders, we found no association between indicators of hypotension, and indicators of cerebral white matter damage or a cerebral palsy diagnosis. CONCLUSION: The absence of an association between indicators of hypotension and cerebral white matter damage and or cerebral palsy suggests that early hypotension may not be important in the pathogenesis of brain injury in ELGANs.

Weight gain in infancy and early childhood is associated with school age body mass index but not intelligence and blood pressure in very low birth weight children.

Rates of weight gain in infancy and early childhood can influence later neurocognitive, metabolic and cardiovascular health. We studied the relationship of weight gain during infancy and early childhood to intelligence quotient (IQ), blood pressure (BP) and body mass index (BMI) at age 9 in children born with very low birth weight (VLBW). Sixty-five children born prematurely with VLBW were followed longitudinally and at 9 years IQ, BP and BMI were measured. The mean weight z-scores at birth, neonatal intensive care discharge, 1 year corrected for prematurity, 5 and 9 years were -0.17, -2.09, -1.3, -0.68 and 0.06, respectively. Weight gain during infancy (discharge to 1 year corrected for prematurity) and early childhood (1 year corrected age to 5 years) was expressed as rate of change in weight, rate of change in weight z-score and interval change in weight z-score. In multiple regression analyses that adjusted for race, gender, maternal education, antenatal steroids, birth weight z-score, major intracranial lesions on ultrasound and chronic lung disease, rates of weight gain in infancy and early childhood were predictive of BMI z-score at 9 years, regression coefficients (95% confidence intervals); 0.19 (0.02, 0.36) and 0.37 (0.11, 0.63), respectively, expressed as change in BMI z-score per 10 g/week weight increase. Rates of weight gain were not predictive of systolic BP z-score, Verbal IQ or Performance IQ. In VLBW infants, more rapid weight gain during infancy, and especially early childhood, is associated with higher BMI at school age.

The ELGAN study of the brain and related disorders in extremely low gestational age newborns.

BACKGROUND: Extremely low gestational age newborns (ELGANs) are at increased risk for structural and functional brain abnormalities. AIM: To identify factors that contribute to brain damage in ELGANs. STUDY DESIGN: Multi-center cohort study. SUBJECTS: We enrolled 1506 ELGANs born before 28 weeks gestation at 14 sites; 1201 (80%) survived to 2 years corrected age. Information about exposures and characteristics was collected by maternal interview, from chart review, microbiologic and histological examination of placentas, and measurement of proteins in umbilical cord and early postnatal blood spots. OUTCOME MEASURES: Indicators of white matter damage, i.e. ventriculomegaly and echolucent lesions, on protocol cranial ultrasound scans; head circumference and developmental outcomes at 24 months adjusted age, i.e., cerebral palsy, mental and motor scales of the Bayley Scales of Infant Development, and a screen for autism spectrum disorders. RESULTS: ELGAN Study publications thus far provide evidence that the following are associated with ultrasongraphically detected white matter damage, cerebral palsy, or both: preterm delivery attributed to preterm labor, prelabor premature rupture of membranes, or cervical insufficiency; recovery of microorganisms in the placenta parenchyma, including species categorized as human skin microflora; histological evidence of placental inflammation; lower gestational age at delivery; greater neonatal illness severity; severe chronic lung disease; neonatal bacteremia; and necrotizing enterocolitis. CONCLUSIONS: In addition to supporting a potential role for many previously identified antecedents of brain damage in ELGANs, our study is the first to provide strong evidence that brain damage in extremely preterm infants is associated with microorganisms in placenta parenchyma.

Heart rate characteristics and neurodevelopmental outcome in very low birth weight infants.

BACKGROUND: Sepsis in very low birth weight (VLBW) infants has been associated with an increased risk of adverse developmental outcome. We have identified abnormal heart rate characteristics (HRCs) that are predictive of impending sepsis, and we have developed a summary measure of an infant's abnormal HRCs during the neonatal hospitalization that we refer to as the cumulative HRC score (cHRC). OBJECTIVE: In this study, we tested the hypothesis that increasing cHRC is associated with an increasing risk of adverse neurodevelopmental outcome in VLBW infants. METHOD: Data were collected on 65 VLBW infants whose HRCs were monitored while in the neonatal intensive care unit and who were examined at 12 to 18 months adjusted age. Using the Bayley Scale of Infant Development-II, we identified delays in early cognitive function (i.e., Mental Developmental Index <70) and psychomotor development (i.e., Psychomotor Developmental Index <70). Cerebral palsy (CP) was diagnosed using a standard neurological examination. RESULT: Increasing cHRC score was associated with an increased risk of CP (odds ratio per 1 standard deviation increase in cHRC: 2.6, 95% confidence limits: 1.42, 5.1) and delayed early cognitive development [odds ratio: 2.3 (1.3; 4.3)]. These associations remain statistically significant when adjusted for major cranial ultrasound abnormality. There was an association of increasing cHRC and delayed psychomotor development, which did not reach statistical significance [odds ratio: 1.7 (1.0, 3.0)]. CONCLUSION: Among VLBW infants, the cumulative frequency of abnormal HRCs, which can be assessed non-invasively in the neonatal intensive care unit, is associated with an increased risk of adverse neurodevelopmental outcome.

Neonatal pulmonary hypertension treated with inhaled nitric oxide and high-frequency ventilation.

UNLABELLED: Term and near-term infants with pulmonary hypertension are frequently treated with inhaled nitric oxide. This therapy can be delivered with high-frequency ventilation, but there has been limited study of the relative effectiveness of high-frequency jet ventilation and high-frequency oscillatory ventilation. OBJECTIVE: To compare short-term clinical outcomes of neonates with pulmonary hypertension treated with inhaled nitric oxide plus either high-frequency jet ventilation or high-frequency oscillatory ventilation. STUDY DESIGN: Study infants met the following criteria: >or=35 weeks gestation, respiratory failure with pulmonary hypertension, no congenital malformations and treatment in the first week of life with inhaled nitric oxide plus either high-frequency jet ventilation (n=22) or high-frequency oscillatory ventilation (n=43). Data were collected from medical records. RESULT: The jet ventilation and oscillatory ventilation groups were similar in terms of gestational age, but the jet ventilation group had less severe respiratory illness (that is, lower oxygenation index) just prior to initiation of the combination of nitric oxide and high-frequency ventilation. The jet ventilation group spent more hours on inhaled nitric oxide (71.4 versus 40.8; P=0.004) but was less likely to require extracorporeal membrane oxygenation (2(9%) versus 19(44%); P=0.004). No difference was found in the ages at which oxygen and high-frequency ventilation were discontinued. CONCLUSION: Term and near-term neonates with pulmonary hypertension who require nitric oxide have similar short-term outcomes regardless of whether nitric oxide is delivered by high-frequency jet ventilation or high-frequency oscillatory ventilation.

Early human milk feeding is associated with a lower risk of necrotizing enterocolitis in very low birth weight infants.

BACKGROUND: Necrotizing enterocolitis (NEC) is a frequent cause of mortality and morbidity in very low birth weight (VLBW) infants. Human milk (HM) feeding has been associated with lower risk of NEC. However, mothers of VLBW infants often experience insufficient milk production, resulting in mixed feedings of HM and formula. Moreover, medical complications often limit the volume of feeding they can be given. OBJECTIVE: To determine if high proportions of (50% or greater) HM enteral feeding within the first 14 days of life are protective against NEC. METHOD: This was a prospective cohort study of VLBW infants who were grouped according to the HM proportion of enteral feeding in the first 14 days: <50% (low human milk, LHM, n=46) and > or =50% (high human milk, HHM, n=156). The outcome of interest was development of NEC (Bell stage 2 or 3). Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) and to assess potential confounding due to perinatal risk factors. RESULT: Two hundred and two infants were studied. Confirmed NEC occurred in 5/46 (10.6%) of the LHM group, as compared with 5/156 (3.2%) of the HHM. Gestational age was the only perinatal factor associated with risk of NEC. After adjustment for gestational age, HHM was associated with a lower risk of NEC ((OR=0.17, 95% CI: 0.04 to 0.68), P=0.01). CONCLUSION: Enteral feeding containing at least 50% HM in the first 14 days of life was associated with a sixfold decrease in the odds of NEC.

Adult stroke and perinatal brain damage: like grandparent, like grandchild?

Biomarkers of inflammation are found in the circulation of adults who have had a stroke. Although these biomarkers may, in part, be indicators of damage, some appear to contribute to damage. Similar biomarkers are found in newborns with cerebral white matter damage or at risk of cerebral palsy. Can we learn about the pathogenesis of neonatal white matter damage from what has been learned about the inflammatory correlates of adult stroke? We discuss relevant findings about systemic inflammatory markers in adult stroke and relate this information to our current understanding of cerebral white matter damage in newborns, especially those born at an extremely low gestational age. We also describe desirable characteristics of future studies of perinatal brain damage that involve measurements of systemic biomarkers.

Perinatal regionalization and neonatal mortality in North Carolina, 1968-1994.

OBJECTIVE: Our purpose was to analyze trends across time in the regionalization of low-birth-weight births and time trends for the association between regionalization and decreased neonatal mortality. STUDY DESIGN: Data on 69,452 neonates with birth weights of 500 to 2000 g were obtained from electronic files of birth certificates. Hospitals' perinatal services were classified as level 1, 2, or 3 (level 3 refers to tertiary referral centers). RESULTS: The likelihood of birth outside level 3 hospitals decreased from 1968 to 1994, with an average annual decrease of 24% for infants weighing 500 to 1500 g and 20% for infants weighing 1501 to 2000 g. After 1974, birth in a hospital with level 3 services was associated with a lower risk of dying. The strength of this association increased in the 1990s. CONCLUSIONS: In North Carolina the proportion of infants weighing <2000 g born outside a hospital with level 3 neonatal services declined from 1974 through 1994. After 1974, birth in a hospital with level 3 neonatal services was associated with lower neonatal mortality.

Mediators of fetal inflammation in extremely low gestational age newborns.

To establish levels of mediators of inflammation in cord blood and postnatal serum from extremely low gestational age newborns (ELGANs, < or =28 weeks), we measured sixteen markers of inflammation by recycling immunoaffinity chromatography in 15 ELGANs who had serum sampled at days 2-5. Median levels of IL-1, IL-6, IL-8, IL-11, IL-13, TNF-alpha, G-CSF, M-CSF, GM-CSF, MIP-1alpha, and RANTES were considerably higher than published values of these inflammatory mediators from term newborns. In three of eight ELGANS who had serial measurements taken, levels of IL-1, IL-6, IL-8, IL-11, TNF-alpha, G-CSF, and MIP-1alpha declined from initially very high levels to reach an apparent baseline towards the end of the first postnatal week. In these same three infants, GM-CSF and TGF-beta1 levels increased continuously during the first week. In the other five ELGANs, no consistent changes were observed. We speculate, that in some ELGANs, a fetal systemic inflammatory response is characterized by an antenatal wave of pro-inflammatory cytokines, followed by a second, postnatal wave of anti-inflammatory cytokines. Large epidemiologic studies are needed to clarify relationships among inflammation markers and their expression in the fetal and neonatal circulation over time. Such studies would also add to our understanding of the possible role of inflammatory mediators in the pathophysiology of the major complications of extreme prematurity.

Perinatal glucocorticoid therapy and neurodevelopmental outcome: an epidemiologic perspective.

A relatively brief course of antenatal glucocorticoids (ACS), given to reduce the severity of respiratory distress syndrome in preterm infants, improves survival and appears to protect against brain damage. In clinical trials as well as observational studies, ACS have been associated with a decreased risk of intraventricular haemorrhage and cerebral palsy. In observational studies a decreased risk of white-matter damage, identified with cranial ultrasound, has been observed. There is some evidence, from observational studies, that repeated courses of ACS (typically given at weekly intervals) can reduce the rate of fetal head growth, and experiments in animals provide further support for this possibility. In contrast to the effects of a brief course of ACS, postnatal glucocorticoids (PCS), given to preterm infants to reduce the severity of chronic lung disease have been associated with an increased risk of neurologic impairment. Available evidence suggests that PCS does not improve survival. Further study is needed of the neurodevelopmental consequences of both multiple courses of ACS, as well as PCS.