Selected Abstracts 2000-2002 Abstracts of some of the recently published articles by members of the Program in Fetal Medicine at Brown.: Karinski DA. Balkundi D. Rubin LP. Padbury JF. The use of inhaled glucocorticosteroids and recovery from adrenal suppression after systemic steroid use in a VLBW premature infant with BPD: case report and literature discussion. Neonatal Network - Journal of Neonatal Nursing. 19(8):27-32, 2000 Dec. Abstract Despite development of many prevention and treatment modalities for bronchopulmonary dysplasia (BPD), a form of chronic respiratory insufficiency in premature infants recovering from respiratory distress syndrome, BPD remains a treatment challenge and a significant cause of long-term morbidity. A ventilator-dependent very low birth weight infant in our newborn special care unit was receiving multiple courses of systemic dexamethasone for severe respiratory failure. The infant demonstrated adrenal suppression manifested by a baseline cortisol concentration below reported levels in infants of similar birth weight and postnatal age. We hypothesized that he had developed adrenal insufficiency as a result of the prolonged systemic steroid administration used to treat his respiratory problems. We further hypothesized that inhaled beclomethasone therapy would aid in the infant's recovery phase during relative adrenal insufficiency--and so substituted inhaled for systemic steroids. Inhaled corticosteroid treatment improved the clinical respiratory course and postnatal growth of this premature infant with BPD without inhibiting his recovery from adrenal insufficiency. [References: 37] Torday JS. Sun H. Wang L. Torres E. Sunday ME. Rubin LP. Leptin mediates the parathyroid hormone-related protein paracrine stimulation of fetal lung maturation. American Journal of Physiology - Lung Cellular & Molecular Physiology. 282(3):L405-10, 2002 Mar. Abstract Developing rat lung lipofibroblasts express leptin beginning on embryonic day (E) 17, increasing 7- to 10-fold by E20. Leptin and its receptor are expressed mutually exclusively by fetal lung fibroblasts and type II cells, suggesting a paracrine signaling "loop." This hypothesized mechanism is supported by the following experimental data: 1) leptin stimulates the de novo synthesis of surfactant phospholipid by both fetal rat type II cells (400% x 100 ng(-1) x ml(-1) x 24 h(-1)) and adult human airway epithelial cells (85% x 100 ng(-1) x 24 h(-1)); 2) leptin is secreted by lipofibroblasts in amounts that stimulate type II cell surfactant phospholipid synthesis in vitro; 3) epithelial cell secretions such as parathyroid hormone-related protein (PTHrP), PGE(2), and dexamethasone stimulate leptin expression by fetal rat lung fibroblasts; 4) PTHrP or leptin stimulate the de novo synthesis of surfactant phospholipid (2- to 2.5-fold/24 h) and the expression of surfactant protein B (SP-B; >25-fold/24 h) by fetal rat lung explants, an effect that is blocked by a leptin antibody; and 5) a PTHrP receptor antagonist inhibits the expression of leptin mRNA by explants but does not inhibit leptin stimulation of surfactant phospholipid or SP-B expression, indicating that PTHrP paracrine stimulation of type II cell maturation requires leptin expression by lipofibroblasts. This is the first demonstration of a paracrine loop that functionally cooperates to induce alveolar acinar lung development. De Paepe ME. Burke S. Luks FI. Pinar H. Singer DB. Demonstration of placental vascular anatomy in monochorionic twin gestations. Pediatric & Developmental Pathology. 5(1):37-44, 2002 Jan-Feb. Abstract Invasive treatment modalities for severe chronic twin-to-twin transfusion syndrome (TTTS), such as fetoscopic laser coagulation of communicating vessels, have revived the need for detailed studies of placental angioarchitecture. We describe a practical placental vascular injection technique using alcohol-resistant tissue-staining dyes. Injection of color-coded gelatin-dye mixtures effectively delineated the intertwin vasculature, and allowed unequivocal macroscopic classification of vascular communications as artery-to-artery, vein-to-vein, or deep artery-to-vein anastomoses. The existence of deep artery-to-vein anastomoses was further confirmed by light microscopic demonstration of venous dye of one twin and arterial dye of the opposite twin within the same stem villus. Furthermore, the injection technique allowed determination of the caliber of the anastomoses, the direction of the artery-to-vein anastomoses, and the relative vascular territory of each twin. Documenting the vascular communications in monochorionic twin placentas with and without TTTS may enhance our understanding of the pathogenesis of chronic TTTS. Correlating the anastomotic patterns and location of the laser coagulation scars with post-ablation outcome will aid in the design of rational therapeutic methods for this often lethal condition. Sanchez-Esteban J. Wang Y. Cicchiello LA. Rubin LP. Cyclic mechanical stretch inhibits cell proliferation and induces apoptosis in fetal rat lung fibroblasts. American Journal of Physiology - Lung Cellular & Molecular Physiology. 282(3):L448-56, 2002 Mar. Abstract Development of the pulmonary air sacs is crucial for extrauterine survival. Late fetal lung development is characterized by a thinning of the mesenchyme, which brings pneumocytes and endothelial cells into apposition. We hypothesized that mechanical stretch, simulating fetal breathing movements, plays an important role in this remodeling process. Using a Flexercell Strain Unit, we analyzed the effects of intermittent stretch on cell proliferation and apoptosis activation in fibroblasts isolated from fetal rat lungs during late development. On day 19, intermittent stretch increased cells in G(0)/G(1) by 22% (P = 0.001) and decreased in S phase by 50% (P = 0.003) compared with unstretched controls. Cell proliferation analyzed by 5-bromo-2'-deoxyuridine incorporation showed a similar magnitude of cell cycle arrest (P = 0.04). At this same gestational age, stretch induced apoptosis by two- to threefold over controls, assayed by DNA flow cytometry, terminal deoxynucleotidyl transferase-mediated dUTP-FITC nick-end labeling, and caspase-3 activation. These results indicate that mechanical stretch of fibroblasts isolated during the canalicular stage inhibits cell cycle progression and activates apoptosis. These findings are cotemporal with the mesenchymal thinning that normally occurs in situ. Sarkar S. Tsai SW. Nguyen TT. Plevyak M. Padbury JF. Rubin LP. Inhibition of placental 11beta-hydroxysteroid dehydrogenase type 2 by catecholamines via alpha-adrenergic signaling. American Journal of Physiology - Regulatory Integrative & Comparative Physiology. 281(6):R1966-74, 2001 Dec. Abstract The placenta expresses high levels of 11beta-hydroxysteroid dehydrogenase type 2 (11betaHSD2) that converts cortisol into inactive 11-keto metabolites and effectively protects the developing fetus from maternal cortisol during pregnancy. Impairment of this glucocorticoid barrier has adverse effects on fetal outcomes. A similar spectrum of adverse fetal effects is induced by antenatal stress during pregnancy. To examine the hypothesis that physiological stress may regulate placental 11betaHSD2 gene expression, we examined the effects of the catecholamines norepinephrine (NE) and epinephrine (E) on 11betaHSD2 expression in human trophoblastic cells. With the use of Northern blotting and semiquantitative RT-PCR, we determined that NE and E rapidly downregulate 11betaHSD2 steady-state mRNA levels in early- and late-gestation human trophoblasts and BeWo trophoblastic cells. Experiments using different adrenoceptor subtype-selective agonists and antagonists demonstrated that this catecholamine suppression of 11betaHSD2 mRNA expression is mediated via both alpha(1)- and alpha(2)-adrenoceptors and is independent of beta-adrenergic stimulation. To examine transcriptional regulation, BeWo cells were transiently transfected with a reporter construct in which an 11betaHSD2 human promoter sequence was inserted upstream of the luciferase gene. Treatment with 10(-7) M NE decreased luciferase activity by ~60% (n = 3, P < 0.01). These results suggest the NE/E-mediated decrease in placental 11betaHSD2 gene expression is an instance of alpha-adrenoceptor-specific rapid transcriptional inhibition of an adrenergic target gene. This molecular mechanism may be involved in the deleterious effects of antenatal physiological stress on fetoplacental growth and development. McNab TC. Tseng YT. Stabila JP. McGonnigal BG. Padbury JF. Liganded and unliganded steroid receptor modulation of beta 1 adrenergic receptor gene transcription. Pediatric Research. 50(5):575-80, 2001 Nov. Abstract The classical model of gene regulation by hormones involves a hormone-bound receptor interacting with a DNA response element to increase or decrease gene transcription. Steroid hormone regulation more commonly involves atypical cis-elements, co-receptors, accessory proteins, and unique modes of interaction on different genes. The thyroid hormone and retinoic acid receptors belong to the super family of steroid nuclear receptors and may modify gene expression even in the absence of ligand binding. In these studies, we characterized thyroid receptor- and retinoic acid receptor-mediated regulation of beta1 adrenergic receptor (beta1AR) gene expression. Using cloned fragments of the ovine beta1AR in a luciferase reporter vector, we examined the effects of thyroid receptor and retinoic acid receptor, alone and in combination with T3 or retinoic acid on beta1AR expression. We examined expression in SK-N-SH neuroblastoma cells, CV-1 fibroblasts, and, in neonatal rat, primary cardiomyocytes. We demonstrated that even in the absence of ligand binding, thyroid receptor and retinoic acid receptor can significantly increase beta1AR transcription activity. This effect is important in the developmental transition in beta1AR expression during fetal and postnatal life.   Rehan VK. Laiprasert J. Wallach M. Rubin LP. McCool FD. Diaphragm dimensions of the healthy preterm infant. Pediatrics. 108(5):E91, 2001 Nov. Abstract BACKGROUND: The diaphragm is the major inspiratory muscle in the neonate; however, human neonatal diaphragm development has not been extensively studied. We hypothesized that diaphragm thickness (t(di)) would be positively related to postmenstrual age (PMA), body weight, body length, head circumference, and nutritional intake. OBJECTIVES: To evaluate the evolution of diaphragm growth and motion in the healthy, preterm infant. METHODS: We used ultrasound to measure t(di) at the zone of apposition to the rib cage and diaphragm excursion (e(di)) during inspiration. Thirty-four stable, preterm infants (16 males and 18 females) between 26 and 37 weeks' PMA were studied during quiet sleep at weekly intervals until the time of discharge or transfer from the neonatal intensive care unit. All infants were clinically stable and not receiving ventilatory support. RESULTS: We found that 1) t(di) increased from 1.2 +/- 0.1 to 1.7 +/- 0.05 mm between 26 to 28 and 35 to 37 weeks' PMA; 2) t(di) was positively correlated with PMA (r = 0.40), body weight (r = 0.52), body length (r = 0.53), and head circumference (0.49), but not with postnatal nutritional intake (r = 0.09); and 3) e(di) decreased with increasing PMA. CONCLUSIONS: Our findings suggest that diaphragm development in premature infants scales with body dimensions. We speculate that the increase in t(di) with age is likely attributable to increased diaphragm muscle mass, and the reduced e(di) with age may be resulting from a reduction in chest wall compliance. Tseng YT. Kopel R. Stabila JP. McGonnigal BG. Nguyen TT. Gruppuso PA. Padbury JF. Beta-adrenergic receptors (betaAR) regulate cardiomyocyte proliferation during early postnatal life. FASEB Journal. 15(11):1921-6, 2001 Sep. Abstract Cardiomyocyte development switches from hyperplasmic to hypertrophic growth between postnatal days 3 and 4 in rats. The mechanisms responsible for this transition have been controversial. beta-Adrenergic receptor (betaAR) activation of mitogenic responses in vitro has been reported. We hypothesized that tonic activation of the betaAR signaling regulates cell division in neonatal cardiomyocytes via effects on signaling kinases known to be important in cell cycle regulation. The purpose of the current study was to elucidate the roles of betaAR in rat cardiomyocyte growth in vivo. We demonstrated that betaAR blockade induced a significant reduction in cardiomyocyte proliferation as measured by the BrdU labeling index. Blockade of betaAR did not affect p38 or p44/42 MAPK activities. We further demonstrated that betaAR blockade induced a prompt deactivation of the p70 ribosomal protein S6 kinase (p70 S6K). To confirm these results, we measured p70 S6K activity directly. Basal activity of p70 S6K in neonatal cardiomyocytes was fourfold higher than that of insulin-treated adult rat liver. The activity of p70 S6K was reduced by 60% within 1 min after betaAR blockade. We conclude that the betaAR are involved in regulation of neonatal cardiomyocyte proliferation and that this mitogenic control may be mediated via the p70 S6K pathway. Al-Aweel I. Pursley DM. Rubin LP. Shah B. Weisberger S. Richardson DK. Variations in prevalence of hypotension, hypertension, and vasopressor use in NICUs. Journal of Perinatology. 21(5):272-8, 2001 Jul-Aug. Abstract OBJECTIVE: Very low birth weight infants are vulnerable to hypotension and its associated complications. Vasopressors are used to raise blood pressure (BP), but indications for use are uncertain. Our objectives were (1) to study variations in BP stability among NICUs, (2) to investigate inter-NICU differences in vasopressor use, and (3) to address the association between intraventricular hemorrhage (IVH) and abnormal BPs. STUDY DESIGN: A total of 1288 infants with birth weight <1500 g were admitted to six NICUs in Massachusetts and Rhode Island over 21 months. The lowest and highest mean BPs were collected within the first 12 hours. Also recorded were the use of vasopressors within the first 24 hours and the occurrence of IVH. Logistic regressions were used to model outcomes, controlling for gestational age and illness severity using the Score for Neonatal Acute Physiology. RESULTS: Two of the six NICUs had significantly higher percentages of infants with at least one hypotensive BP, with prevalences of 24% to 45%. Percentages of infants treated with vasopressors ranged from 4% to 39%. This range of vasopressor use could not be explained by inter-NICU differences in birth weight, illness severity, or rates of hypotension. We found a borderline association between severe IVH and hypotension (odds ratio 1.6, p=0.055), but not between severe IVH and hypertension. CONCLUSION: Wide differences exist in the prevalence of hypotension, hypertension, and vasopressor use among NICUs. We also found an association between hypotension and IVH, but not between hypertension and IVH. Luks FI. Carr SR. Ponte B. Rogg JM. Tracy TF Jr. Preoperative planning with magnetic resonance imaging and computerized volume rendering in twin-to-twin transfusion syndrome. American Journal of Obstetrics & Gynecology. 185(1):216-9, 2001 Jul. Abstract Our purpose was to illustrate the feasibility of preoperative planning with magnetic resonance imaging, 3-dimensional reconstruction, and volume-rendering techniques in twin-to-twin transfusion syndrome treated by endoscopic laser ablation of communicating vessels. After ultrasonographic determination of the syndrome and the indications for intervention, 2 patients with an anterior placenta underwent magnetic resonance imaging without the need for maternal or fetal sedation. Raw image data were downloaded into a desktop computer and manipulated with 3-dimensional reconstruction, volume rendering, and surgical navigation software. In both patients a virtual rendering of the fetuses, placenta, and uterus could be manipulated to expose all sides, demonstrate the location of the intertwin membrane, and plan the point of entry and curve of the endoscopic instruments. Preoperative planning and virtual surgical navigation in fetal surgery are now possible, as a result of shorter magnetic resonance imaging acquisition times and volume-rendering software. In this manner an entire virtual endoscopic fetal operation can be performed and fine-tuned before the actual procedure is to take place. Newnham JP. Moss TJ. Padbury JF. Willet KE. Ikegami M. Ervin MG. Sly P. Jobe A. The interactive effects of endotoxin with prenatal glucocorticoids on short-term lung function in sheep. American Journal of Obstetrics & Gynecology. 185(1):190-7, 2001 Jul. Abstract OBJECTIVE: Previously we have shown that neonatal lung function in sheep after preterm birth is profoundly enhanced by intra-amniotic injection of endotoxin, with a magnitude at least equal to that induced by maternal betamethasone administration. This study investigated the effects of betamethasone on lung maturation and growth in the presence of inflammation by treating sheep with both maternal intramuscular betamethasone and intra-amniotic endotoxin injections. STUDY DESIGN: Time-mated pregnant ewes at 118 days' gestation were allocated at random to receive maternal intramuscular or intra-amniotic saline solution injection (n = 10), maternal intramuscular betamethasone injection (0.5 mg/kg; n = 7), intra-amniotic endotoxin injection (20 mg Escherichia coli B055;B5; n = 11) by ultrasonographic guidance, or both betamethasone and endotoxin injections (n = 7). The lambs were delivered abdominally at 125 days' gestation (term is 150 days' gestation), and the neonates were ventilated for 40 minutes before postmortem examination. RESULTS: Combined treatment with betamethasone and endotoxin resulted in significantly greater improvements in neonatal lung function than occurred after treatment with either agent alone, and this effect was not accompanied by a further increase in surfactant levels. The reduction in birth weight that is seen after maternal betamethasone treatment was not seen when this treatment was combined with endotoxin. Endotoxin treatment resulted in inflammatory responses in cord blood and alveolar wash, and these responses were not inhibited by betamethasone treatment. There were no pregnancy losses. CONCLUSION: Both intra-amniotic endotoxin injection and maternal intramuscular betamethasone injection promoted fetal lung maturation. When these treatments were combined, there were additive effects on short-term postnatal lung function but not on surfactant levels. Endotoxin negated the growth restriction in sheep caused by maternal betamethasone treatment. These findings provide evidence that the lung maturation induced by glucocorticoids and that induced by endotoxin are mediated by different mechanisms. Tseng YT. Stabila JP. Nguyen TT. McGonnigal BG. Waschek JA. Padbury JF. A novel glucocorticoid regulatory unit mediates the hormone responsiveness of the beta1-adrenergic receptor gene. Molecular & Cellular Endocrinology. 181(1-2):165-78, 2001 Jul 5. Abstract The effects of glucocorticoids on expression of the beta1-adrenergic receptor (beta1AR) gene have been varied. To study the mechanism underling hormonal regulation of the beta1AR, transient transfection of progressively deleted ovine beta1AR promoter fragments was used to identify a 43-bp region (-1274 to -1232 from the translation start site) that contains a novel glucocorticoid regulatory unit (GRU) and confers glucocorticoid responsiveness. Using DNase I footprinting and electrophoretic mobility shift assays (EMSA), we demonstrated the GRU was composed of a palindrome, 5'-TAATTA-3', which is a core binding motif for the homeodomain proteins, an E-box (5'-CACGTG-3'), binding site for the Myc/Max family proteins, and an overlapping glucocorticoid response element (GRE) half-site (5'-TGTTCT-3'). EMSA demonstrated that the GRE half-site is critical for GRU-protein interactions, which also require binding of proteins to the E-box and the homeodomain region. Co-transfection of a plasmid expressing a c-myc antisense construct significantly reduced glucocorticoid responsiveness of the ovine beta1AR promoter. Furthermore, expression of proteins binding to the GRU was shown to be developmentally regulated, being high in embryonic, reduced in newborn and not detectable in adult heart. We conclude that the ovine beta1AR promoter contains a novel, functional GRU and that glucocorticoid receptor (GR) and the Myc/Max family proteins are involved in the cell-specific nuclear factor binding and transactivation via this element. The results suggest an alternative pathway through which glucocorticoids may exert their effects on genes lacking a full consensus GRE. Sanchez-Esteban J. Cicchiello LA. Wang Y. Tsai SW. Williams LK. Torday JS. Rubin LP. Mechanical stretch promotes alveolar epithelial type II cell differentiation. Journal of Applied Physiology. 91(2):589-95, 2001 Aug. Abstract Functional maturation of pulmonary alveolar epithelial cells is crucial for extrauterine survival. Mechanical distension and mesenchymal-epithelial interactions play important roles in this process. We hypothesized that mechanical stretch simulating fetal breathing movements is an important regulator of pulmonary epithelial cell differentiation. Using a Flexercell Strain Unit, we analyzed effects of stretch on primary cultures of type II cells and cocultures of epithelial and mesenchymal cells isolated from fetal rat lungs during late development. Cyclic stretch of isolated type II cells increased surfactant protein (SP) C mRNA expression by 150 +/- 30% over controls (P < 0.02) on gestational day 18 and by 130 +/- 30% on day 19 (P < 0.03). Stretch of cocultures with fibroblasts increased SP-C expression on days 18 and 19 by 170 +/- 40 and 270 +/- 40%, respectively, compared with unstretched cocultures. On day 19, stretch of isolated type II cells increased SP-B mRNA expression by 50% (P < 0.003). Unlike SP-C, addition of fibroblasts did not produce significant additional effects on SP-B mRNA levels. Under these conditions, we observed only modest increases in cellular immunoreactive SP-B, but secreted saturated phosphatidylcholine rose by 40% (P < 0.002). These results indicate that cyclic stretch promotes developmentally timed differentiation of fetal type II cells, as a direct effect on epithelial cell function and via mesenchymal-epithelial interactions. Expression of the SP-C gene appears to be highly responsive to mechanical stimulation. Carpenter MW. Canick JA. Hogan JW. Shellum C. Somers M. Star JA. Amniotic fluid insulin at 14-20 weeks' gestation: association with later maternal glucose intolerance and birth macrosomia. Diabetes Care. 24(7):1259-63, 2001 Jul. Abstract OBJECTIVE: To examine the hypothesis that early second trimester amniotic fluid (AF) insulin concentration is elevated and later fetal growth is augmented in gravidas demonstrating later oral glucose intolerance. RESEARCH DESIGN AND METHODS: In this prospective observational cohort study, AF was sampled at 14-20 weeks' gestation in 247 subjects, and 1-h 50-g oral glucose challenge tests (GCTs) were performed at > or = 24 weeks. AF insulin was assayed by an automated immuno-chemiluminometric assay (8). Macrosomia was defined as birth weight above the 90th centile. RESULTS: AF insulin concentration (range 1.4-44.5 pmol/l) correlated positively with gestational age and maternal weight. A logistic regression analysis, adjusted for maternal age and midpregnancy weight, showed increased AF insulin multiples of gestational age-specific medians to be associated with subsequently diagnosed gestational diabetes mellitus (GDM) (OR 1.9, CI 1.3-2.4, P = 0.029). Among 60 subjects with GCT values > 7.2 mmol/l, each unit increase in AF insulin multiple of median (MOM) was associated with a threefold increase in fetal macrosomia incidence (3.1, 1.3-4.9, P = 0.048). CONCLUSIONS: An elevated AF insulin concentration at 14-20 weeks' gestation is associated with subsequently documented maternal glucose intolerance. Among gravidas with GCT values > 7.2 mmol/l, elevated early AF insulin concentration is associated with fetal macrosomia. Maternal glucose intolerance may affect fetal insulin production before 20 weeks' gestation.   Burgess GH. Oh W. Brann BS 4th. Brubakk AM. Stonestreet BS. Effects of phenobarbital on cerebral blood flow velocity after endotracheal suctioning in premature neonates. Archives of Pediatrics & Adolescent Medicine. 155(6):723-7, 2001 Jun. Abstract OBJECTIVE: To examine the effect of phenobarbital administration on anterior cerebral artery blood flow velocity before and after endotracheal suctioning in premature neonates. DESIGN: Transcutaneous PO(2) (TcPO(2)), heart rate, mean arterial blood pressure (MABP), and Doppler velocimeter blood flow of the left anterior cerebral artery were measured before and immediately after 3 consecutive endotracheal suctioning procedures in premature neonates. Intravenous phenobarbital (20 mg/kg) was administered immediately after the first procedure. SETTING: Neonatal intensive care unit. PATIENTS: Nine neonates with a mean birth weight of 807 g (range, 620-1060 g) and a mean gestational age of 27 weeks (range, 25-30 weeks) were studied at age 8 to 12 hours. RESULTS: Transcutaneous PO(2) decreased in response to endotracheal suctioning at each of the suctioning procedures before and after phenobarbital was given (P<.001). Changes in heart rate were not observed. There were increases in MABP and area under the velocity curve (AUVC) per minute in response to endotracheal suctioning before but not after phenobarbital administration (P=.046). Use of phenobarbital lowered the overall peak systolic blood flow velocity in response to endotracheal suctioning (P =.02, analysis of variance, interactions for the effect of phenobarbital therapy on the response to suctioning). Changes in end-diastolic blood flow velocity were not observed. There were decreases in the differences before and after endotracheal suctioning for MABP at 2 and 4 hours and for AUVC and peak systolic blood flow velocity 4 hours after phenobarbital was given (P =.04). CONCLUSIONS: In very low-birth-weight neonates, endotracheal suctioning is associated with decreases in TcPO(2) and increases in MABP and AUVC. Treatment with phenobarbital attenuates the increases in MABP and AUVC but not the decreases in TcPO(2) after endotracheal suctioning. Yamamoto H. Lambert-Messerlian GM. Silver HM. Kudo R. Kellner LH. Canick JA. Maternal serum levels of type I and type III procollagen peptides in pre-eclamptic pregnancy. Journal of Maternal-Fetal Medicine. 10(1):40-3, 2001 Feb. Abstract OBJECTIVE: To compare maternal serum levels of two markers of collagen synthesis, procollagen I carboxy-terminal peptide (PICP) and procollagen III amino-terminal peptide (PIIINP), in patients with pre-eclampsia and in controls. METHODS: PICP and PIIINP were measured by radioimmunoassay in maternal serum samples from patients diagnosed with pre-eclampsia at 32 weeks' gestation or later and in controls from the same period of gestation. For PICP, 37 cases and 36 controls were studied; for PIIINP, 12 cases and 19 controls were studied. RESULTS: Both PICP and PIIINP levels were significantly elevated in patients with pre-eclampsia. PICP and PIIINP levels were, on average, 20% and 80% higher than in controls, respectively. CONCLUSIONS: These results are in agreement with previous findings that maternal serum levels of PICP and PIIINP are mildly elevated in patients with pre-eclampsia. These markers are unlikely to be useful in the prediction of pre-eclampsia. Diah SK. Padbury JF. Campbell WA. Britt D. Thompson NL. Molecular cloning of the rat TA1/LAT-1/CD98 light chain gene promoter. Biochimica et Biophysica Acta. 1518(3):267-70, 2001 Apr 16. Abstract The rat LAT-1 (L-amino acid transporter-1) gene is a CD98 light chain highly expressed in cancer and development. As an initial study of the molecular basis underlying regulation of its expression, we cloned 2 kb of the LAT-1 5' flanking region. Inverse RACE and primer extension methods were used to define the transcription initiation site at 80 bp upstream from the translational start site. Functional studies carried out in normal hepatic cells using constructs containing progressive 5' deletion from region -1958 to -185 showed 3-5-fold beta-galactosidase activities over control. The presence of an activator site(s) between -52 and -185 was indicated by low activities conferred by the construct spanning this region.   Yasuhi I. Hogan JW. Canick J. Sosa MB. Carpenter MW. Midpregnancy serum C-peptide concentration and subsequent pregnancy-induced hypertension. Diabetes Care. 24(4):743-7, 2001 Apr. Abstract OBJECTIVE: To test the hypothesis that elevated midpregnancy serum insulin (IRI) and C-peptide (CP) concentrations are associated with later development of pregnancy-induced hypertension (PIH), independent of prepregnancy obesity and midpregnancy blood pressure. RESEARCH DESIGN AND METHODS: In this prospective study, a cohort of normotensive women, ages > or = years performed a 50-g glucose challenge test at 24-30 weeks' gestational age. Blood samples were collected after an overnight fast and 1 h after glucose ingestion. Serum IRI and CP concentrations were measured in each sample. Maternal height, blood pressure and proteinuria were measured at the time of glucose challenge testing and after 36 weeks' gestational age. RESULTS: Of 320 subjects enrolled 44 women (13.8%) had subsequent PIH. Crude odds ratios (ORs) for devevelopment of PIH associated with each 1 U rise in log fasting IRI, log lasting CP. and glucosed-induced increase in CP (expressed as log [postprandial CP/fasting CP]) were 2.0 (95% CI 1.3-3.3), 1.8 (CI 1.2-2.7), and 2.3 (CI 1.1-4.9) respectively. After controlling for prepregnancy BMI, gestational age, and midpregnancy mean arterial pressure, adjusted ORs corresponding to log fastig IRI and CP for the development of PIH were 1.3 (95% CI 0.7-2.3) and 1.7 (CI 1.1-2.7) respectively, and, afterq adjustment for fasting CP, the adjusted OR of the glucose-induced rise in log CP was 3.7 (CI 1.5-9.3). CONCLUSIONS: Mid-pregnancy tasting and postoral glucose CP levels are associated with subsequent development of PIH, independent of maternal obesity and midpregnancy baseline blood pressure. These findings many reflect an amplified beta3-cell response to glycemic stimulus, similar to that found in states of insulin resistance, that appears to be independently associated with PIH. Sysyn GD. Petersson KH. Patlak CS. Sadowska GB. Stonestreet BS. Effects of postnatal dexamethasone on blood-brain barrier permeability and brain water content in newborn lambs. American Journal of Physiology - Regulatory Integrative & Comparative Physiology. 280(2):R547-53, 2001 Feb. Abstract We showed that antenatal corticosteroids reduced blood-brain barrier permeability in fetuses at 60 and 80%, but not 90% of gestation, and decreased brain water content in fetuses. Our objective was to examine the effects of postnatal corticosteroids on regional blood-brain barrier permeability and brain water content in newborn lambs. Three dexamethasone treatment groups were studied in 3- to 5-day-old lambs. A 0.01 mg/kg dose was selected to estimate the amount of dexamethasone that might have reached fetuses via antenatal treatment of ewes in our previous studies. The other doses (0.25 and 0.5 mg/kg) were chosen to approximate those used clinically to treat infants with bronchopulmonary dysplasia. Lambs were randomly assigned to receive four intramuscular injections of dexamethasone or placebo given 12 h apart on days 3 and 4 of age. Blood-brain barrier function was measured with the blood-to-brain transfer constant (K(i)) to alpha-aminoisobutyric acid, brain plasma volume was measured with polyethylene glycol for the calculation of K(i,) and brain water was measured by wet-to-dry tissue weights. Postnatal treatment with corticosteroids did not reduce barrier permeability in newborn lambs. Brain blood volume was higher in the 0.25 and 0.5 mg/kg dose dexamethasone groups than in the placebo group. Brain water content did not differ among the groups. We conclude that postnatal treatment with corticosteroids did not reduce regional blood-brain barrier permeability or brain water content but increased the brain plasma volume in newborn lambs. These findings are consistent with our previous work indicating that barrier permeability is responsive to corticosteroids at 60 and 80% of gestation and brain water regulation at 60% of gestation, but not in near-term fetuses or newborn lambs. Thureen PJ. Padbury JF. Hay WW Jr. The effect of maternal hypoaminoacidaemia on placental uptake and transport of amino acids in pregnant sheep. Placenta. 22(2-3):162-70, 2001 Feb-Mar. Abstract We developed a model of maternal hyperglycaemia with secondary hyperinsulinaemia and hypoaminoacidaemia in pregnant sheep (H) to determine the effect of these conditions on uterine, uteroplacental and fetal amino-acid uptake rates and fetal amino-acid concentrations [AA]. Results were compared with normal pregnant ewes (C). Plasma glucose concentrations were greater in H versus C animals: 7.7+/-0.3 versus 3.9+/-0.1 mmol/l maternal, P< 0.005; 2.6+/-0.1 versus 1.1+/-0.1 mmol/l fetal, P< 0.005. Maternal insulin concentrations [I] were greater in the H group (132+/-30 H versus 31+/-5 C microU/ml, P< 0.005); fetal [I] were not different (15+/-2 H versus 16+/-2 C microU/mL). Maternal [AA] were lower in H than C groups except for SER (P=ns) and GLY (approx twofold higher, P< 0.01). Uterine, uteroplacental and fetal uptake rates of several AA, particularly the branch chain AA, were lower in H than C animals, producing lower total fetal nitrogen uptake rates (270+/-64 mg N/kg fetus/day H, 696+/-75 mg N/kg fetus/day C, P=0.001) and lower fetal plasma concentrations for the branch chain AA. Most fetal [AA], however, remained at control values, which could occur by relative increase in fetal amino-acid production and/or decrease in utilization, but not by increased uteroplacental transport rates. Copyright 2001 Harcourt Publishers Ltd. Luks FI. Roggin KK. Wild YK. Piasecki GJ. Rubin LP. Lesieur-Brooks AM. De Paepe ME. Effect of lung fluid composition on type II cellular activity after tracheal occlusion in the fetal lamb. Journal of Pediatric Surgery. 36(1):196-201, 2001 Jan. Abstract BACKGROUND/PURPOSE: Fetal tracheal occlusion (TO) causes accelerated lung growth. However, prolonged TO is associated with a decline in the type II cell number. Type II cell function after TO is unclear. Herein, the authors examine type II cell function after TO and the role of tracheal fluid. METHODS: Fetal lambs (term, 145 days) underwent TO at 122 days. Tracheal pressure was recorded daily. In one group of animals (TF; n = 6), lung fluid was aspirated, measured, and reinfused daily. In their respective twins, NS group, lung fluid was replaced milliliter per milliliter with normal saline (NS; n = 6). At death near term, lung weight was obtained, and tissues were processed for stereologic volumetry. Type II cells were quantitated using antisurfactant protein B immunohistochemistry. Surfactant protein B-mRNA expression was studied by Northern analysis. Wilcoxon signed rank test and single factor analysis of variance (ANOVA) were used for statistical analysis (P<.05 was significant). RESULTS: In both experimental groups, intratracheal pressure rose from 1.9+/-1.0 torr to 3.7 to 4.8 torr by day 1, and remained constant thereafter. Lung fluid volume increased from 11.9+/-4.2 on day 0 to 36.8+/-8.0 mL/kg in TF, and to 28.4+/-9.3 mL/kg in NS by day 1 (P<.05). At death, lung weight/body weight ratio was higher in TF (5.45% +/- 0.91%) than in NS (4.40% +/- 0. 67%) or control (3.83%+/-0.58%; P<.05). Type II numerical density was substantially reduced after TO: 57.7+/-12.8 x 10(6)/mL (TF) and 45.0 +/-25.9 x 10(6)/mL (NS), versus 82.3+/-13.6 x 10(6)/mL in controls. Ultrastructurally, remaining type II cells in TF were enlarged and engorged with lamellar bodies; in NS, they were smaller and contained fewer lamellar bodies. Surfactant protein B mRNA expression was significantly decreased in NS, but not in TF, compared with controls. CONCLUSIONS: Type II cell function as well as overall lung growth are stimulated by TO. Lung growth after TO is therefore not unavoidably detrimental to type II cells. After isobaric saline exchange of lung fluid, type II cell function is severely inhibited, confirming the role of tracheal fluid composition in type II stimulating type II cell function. Buck GM. Msall ME. Schisterman EF. Lyon NR. Rogers BT. Extreme prematurity and school outcomes. Paediatric and Perinatal Epidemiology. 14(4):324-31, 2000 Oct. Abstract The purpose of this study was to assess the impact of extreme prematurity on three global measures of school outcomes. Using a matched cohort design, exposed infants comprised all surviving singleton infants < or = 28 weeks gestation born at one regional neonatal intensive care hospital between 1983 and 1986 (n = 132). Unexposed infants comprised randomly selected full-term infants (> or = 37 weeks gestation) frequency matched on date of birth, zip code and health insurance. All children were selected from a regional tertiary children's centre serving western New York population. Standardised telephone interviews elicited information on grade repetition, special education placement and use of school-based services. Unconditional logistic regression was used to estimate odds ratios (OR) and corresponding 95% confidence intervals (CI) adjusted for potential confounders for children without major handicaps. Extreme prematurity was associated with a significant increase in risk of grade repetition (OR = 3.22; 95% CI = 1.63, 6.34), special education placement (OR = 3.16; 95% CI = 1.14, 8.76) and use of school-based services (OR = 4.56; 95% CI = 1.82, 11.42) in comparison with children born at term, even after controlling for age, race, maternal education, foster care placement and the matching factors. These findings suggest that survivors of extreme prematurity remain at risk of educational underachievement. Goodwin KM. Sweeney PJ. Lambert-Messerlian GM. Canick JA. High maternal serum inhibin A levels following the loss of one fetus in a twin pregnancy. Prenatal Diagnosis. 20(12):1015-7, 2000 Dec. Abstract Inhibin A levels are elevated in the second trimester of pregnancies affected with fetal Down syndrome, on average, two times the level in unaffected pregnancies. Inhibin A levels are also two times higher in twin than in singleton pregnancies. Prenatal serum screening using inhibin A levels as a second trimester marker began at the Women and Infants Hospital in March 1998. We describe a case of a 17-year-old woman thought to have had a complete spontaneous abortion of a twin pregnancy but later found to be continuing the pregnancy with a single fetus. Routine second trimester prenatal serum screening revealed an extremely elevated inhibin A level of 39 MoM (multiples of the median). The patient delivered an apparently healthy female infant at 41 weeks of gestation. Therefore, inhibin A may be extremely elevated in the second trimester of a twin pregnancy after the loss of one fetus and this increased inhibin A level does not have any obvious adverse maternal or fetal effects. Copyright 2000 John Wiley & Sons, Ltd. Padbury JF. McGonnigal B. Tseng YT. Nguyen TT. Stabila JP. Cloning and sequence analysis of the rat norepinephrine transporter promoter. Brain Research. Molecular Brain Research. 83(1-2):128-32, 2000 Nov 10. Abstract We isolated a 2.5-kb fragment of the promoter for the rat norepinephrine transporter (NET) gene. The transcription start site was identified approximately 200 base pairs upstream from the translation start site. Several potential regulatory elements were identified by sequence analysis. The structure of the rat NET promoter was compared to mouse and human. Expression studies in placental and neuroblastoma cells suggested the presence of a 'repressor' element more than 500 base pairs upstream from the transcription start site. These studies provide the basis for examination of transcriptional regulation of this gene and for understanding its temporal and tissue-specific modes of regulation.   - Esposito MA. Menihan CA. Malee MP. Association of interpregnancy interval with uterine scar failure in labor: a case-control study. American Journal of Obstetrics & Gynecology. 183(5):1180-3, 2000 Nov. Abstract OBJECTIVE: The aim of this study was to determine whether a short interpregnancy interval is associated with uterine scar failure in laboring patients with previous low transverse cesarean delivery. STUDY DESIGN: This was a case-control study of uterine scar failures among laboring patients with previous low transverse cesarean delivery. Control patients underwent abdominal delivery during labor after failure of an attempted vaginal birth after cesarean delivery in the same month as case patients. RESULTS: An interpregnancy interval of <6 months was significantly more prevalent among case patients with uterine scar failure (P =.02). Mean interpregnancy interval was less in all cases of uterine scar failure (P = .06). CONCLUSIONS: Interpregnancy interval was inversely associated with likelihood of uterine scar failure during subsequent labor. Jobe AH. Newnham JP. Willet KE. Moss TJ. Gore Ervin M. Padbury JF. Sly P. Ikegami M. Endotoxin-induced lung maturation in preterm lambs is not mediated by cortisol. American Journal of Respiratory & Critical Care Medicine. 162(5):1656-61, 2000 Nov. Abstract Antenatal exposure to glucocorticoids, amnionitis, intraamniotic interleukin (IL)-1alpha, or endotoxin can improve postnatal lung function after preterm delivery. The relationship between early lung maturation and the dose and duration of a proinflammatory stimulus has not been evaluated. The effects of proinflammatory stimuli on fetal plasma cortisol also have not been evaluated. We hypothesized that intraamniotic endotoxin would induce early lung maturation in fetal sheep without increasing fetal cortisol. Intraamniotic injections of 1, 4, 20, or 100 mg of Escherichia coli 055:beta5 endotoxin caused 2-fold increases in compliance, 4- to 5-fold increases in lung gas volumes, and 20-fold increases in alveolar saturated phosphatidylcholine (Sat PC) when given 7 d before preterm delivery at 125 d gestation. Animals treated with 20 mg endotoxin for treatment to delivery intervals of 5 h to 15 d had no significant elevations in cord plasma cortisol levels. Increases in Sat PC in lung tissue and alveolar washes were detected 2 d after endotoxin treatment and lung function improved 4 d after endotoxin treatment. Two doses of endotoxin given 3 and 7 d or 7 and 15 d before treatment resulted in lung maturation responses equivalent to single dose comparison groups without elevations in cortisol. Early lung maturation induced by intraamniotic endotoxin in fetal sheep occurred without an increase in fetal plasma cortisol, indicating that endotoxin promoted lung maturation by a mechanism independent of cortisol. Msall ME. Phelps DL. DiGaudio KM. Dobson V. Tung B. McClead RE. Quinn GE. Reynolds JD. Hardy RJ. Palmer EA. Severity of neonatal retinopathy of prematurity is predictive of neurodevelopmental functional outcome at age 5.5 years. Behalf of the Cryotherapy for Retinopathy of Prematurity Cooperative Group. Pediatrics. 106(5):998-1005, 2000 Nov. Abstract OBJECTIVE: The purpose of this study was to assess the relation between neonatal retinopathy of prematurity (ROP) in very low birth weight infants and neurodevelopmental function at age 5.5 years. METHODS: Longitudinal follow-up of children occurred in 2 cohorts of the Multicenter Cryotherapy for Retinopathy of Prematurity Study. The extended natural history cohort followed 1199 survivors of <1251 g birth weight from 5 centers. The threshold randomized cohort (ThRz) followed 255 infants <1251 g from 23 centers who developed threshold ROP and who consented to cryotherapy to not more than 1 eye. At 5.5 years both cohorts had ophthalmic and acuity testing and neurodevelopmental functional status determined with the Functional Independence Measure for Children (WeeFIM). RESULTS: Evaluations were completed on 88.7% of the extended natural history cohort; 87% had globally normal functional skills (WeeFIM: >95). As ROP severity increased, rates of severe disability increased from 3.7% among those with no ROP, to 19.7% of those with threshold ROP. Multiple logistic regression analysis demonstrated that better functional status was associated with favorable visual acuity, favorable 2-year neurological score, absence of threshold ROP, having private health insurance, and black race. Evaluations were completed on 87.4% of the ThRz children. In each functional domain, the 134 children with favorable acuity in their better eye had fewer disabilities than did the 82 children with unfavorable acuity: self-care disability 25.4% versus 76.8%, continency disability 4.5% versus 50.0%, motor disability 5.2% versus 42.7%, and communicative-social cognitive disability 22.4% versus 65.9%, respectively. CONCLUSION: Severity of neonatal ROP seems to be a marker for functional disability at age 5. 5 years among very low birth weight survivors. High rates of functional limitations in multiple domains occur in children who had threshold ROP, particularly if they have unfavorable visual acuity. De Paepe ME. Rubin LP. Jude C. Lesieur-Brooks AM. Mills DR. Luks FI. Fas ligand expression coincides with alveolar cell apoptosis in late-gestation fetal lung development. American Journal of Physiology - Lung Cellular & Molecular Physiology. 279(5):L967-76, 2000 Nov. Abstract Apoptosis plays a central role in the cellular remodeling of the developing lung. We determined the spatiotemporal patterns of the cell death regulators Fas and Fas ligand (FasL) during rabbit lung development and correlated their expression with pulmonary and type II cell apoptosis. Fetal rabbit lungs (25-31 days gestation) were assayed for apoptotic activity by terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling (TUNEL) and DNA size analysis. Fas and FasL expression were analyzed by RT-PCR, immunoblot, and immunohistochemistry. Type II cell apoptosis increased significantly on gestational day 28; the type II cell apoptotic index increased from 0.54 +/- 0.34% on gestational day 27 to 3.34 +/- 1.24% on day 28, P < 0.01 (ANOVA). This corresponded with the transition from the canalicular to the terminal sac stage of development. The day 28 rise in epithelial apoptosis was synchronous with a robust if transient 20-fold increase in FasL mRNA and a threefold increase in FasL protein levels. In contrast, Fas mRNA levels remained constant, suggestive of constitutive expression. Fas and FasL proteins were immunolocalized to alveolar type II cells and bronchiolar Clara cells. The correlation of this highly specific pattern of FasL expression with alveolar epithelial apoptosis and remodeling implicates the Fas/FasL system as a potentially important regulatory pathway in the control of postcanalicular alveolar cytodifferentiation. Abuelo DN. Ahsanuddin AN. Mark HF. Distal 5q trisomy resulting from an X;5 translocation detected by chromosome painting. American Journal of Medical Genetics. 94(5):392-9, 2000 Oct 23. Abstract We describe the case of a 13-year-old girl with an apparently de novo unbalanced translocation resulting in the presence of additional chromosomal material on the short arm of one X chromosome, which was detected by conventional G-banding studies. Fluorescence in situ hybridization (FISH) using the Chromoprobe Multiprobe-M protocol confirmed that the additional chromosomal material originated from chromosome 5. The karyotype of this patient is now established to be 46,X,der(X) t(X;5)(p22.3;q33), with a deletion of Xp22.3-pter and partial trisomy of 5q33-qter. The distal 5q trisomy genotype has been associated with clinical signs that include growth and mental retardation, eczema, craniofacial anomalies, and malformations of heart, lungs, abdomen, limbs, and genitalia. Our patient also has short stature, a prominent nasal bridge, a flat philtrum, a thin upper lip, dental caries, and limb and cardiac malformations, but she appears to be mildly affected compared with previously reported cases. This is the first case of distal 5q trisomy arising from a translocation with the X chromosome. Replication studies on this patient show that the derivative t(X;5) chromosome is late replicating in almost all cells examined, which indicates that this chromosome is preferentially inactivated. However, the translocated segment of chromosome 5 appears to be early replicating, which implies that the trisomic 5q segment is transcriptionally active. We cannot determine from these studies whether all or only some genes in this segment are expressed, but this patient's relatively mild clinical signs suggest that the critical region(s) that contribute to the distal 5q trisomy phenotype are at least partly suppressed. A review of other patients with X-chromosome translocations indicates that many but not all of them also have attenuated phenotypes. The mechanism of inactivation of autosomal material attached to the X chromosome is complex, with varying effects on the phenotype of the patients that depend on the nature of the autosomal chromatin. Replication studies are of limited utility in predicting expression of autosomal genes involved in X-chromosome translocations. Copyright 2000 Wiley-Liss, Inc. McGowan JE. Sysyn G. Petersson KH. Sadowska GB. Mishra OP. Delivoria-Papadopoulos M. Stonestreet BS. Effect of dexamethasone treatment on maturational changes in the NMDA receptor in sheep brain. Journal of Neuroscience. 20(19):7424-9, 2000 Oct 1. Abstract The objective of the present study was to examine the effect of antenatal or postnatal treatment with corticosteroids on the NMDA receptor, one of the mediators of both normal brain development and hypoxic-ischemic injury, by determining the characteristics of the receptor MK-801 binding site in untreated and corticosteroid-treated fetal and newborn lambs. (3)H-MK-801 binding was performed in cerebral cortical cell membranes from fetal sheep at 88, 120, and 136 d gestation (term = 150 d), and from 5-d-old lambs and adult ewes. Animals were randomized to receive dexamethasone [fetuses: 6 mg, i.m. every 12 hr for four doses to mother; lambs: 0.01 mg/kg (low dose) or 0.25 mg/kg (high dose) every 12 hr for four doses] or placebo. During development, B(max) (apparent number of receptors) increased, reaching a maximum in 5-d-old lambs (p < 0.05) and decreasing in the adult brain. K(d) (dissociation constant) did not change, suggesting that receptor affinity was not altered during maturation. Dexamethasone treatment had no effect on MK-801 binding in the fetus or adult, but in lambs was associated with a significant decrease in B(max) from 2.17 +/- 0.18 pmol/mg protein in placebo-treated animals to 1.65 +/- 0.8 and 1.62 +/- 0.07 pmol/mg protein in low-dose and high-dose animals, respectively. Affinity for (3)H-MK-801 decreased 20% after dexamethasone treatment in lambs only (p < 0.05). Thus, dexamethasone treatment appears to modify the NMDA receptor only during a specific period of brain development. Rausch DN. Lambert-Messerlian GM. Canick JA. Participation in maternal serum screening for Down syndrome, neural tube defects, and trisomy 18 following screen-positive results in a previous pregnancy. Western Journal of Medicine. 173(3):180-3, 2000 Sep. Abstract OBJECTIVE: To determine whether women who have had a positive serum screening result for Down syndrome or neural tube defect in 1 pregnancy have a lower rate of participation in screening in their next pregnancy. SETTING: A triple-marker screening program at a university hospital. METHODS: Pregnancy and screening information was collected from laboratory and hospital databases to compare subsequent screening participation of women who were screen-negative and screen-positive for the risk of a fetus with Down syndrome or a neural tube defect. RESULTS: In an age-matched comparison, 108 women who had a previous screen-positive result were significantly less likely than 108 women who were screen-negative to participate in maternal serum screening in their next pregnancy. When examined according to the type of screen-positive result, the effect was significant for both those who were screen-positive for Down syndrome and those who were screen-positive for neural tube defect. The degree of risk in screen-positive women did not significantly affect their participation in screening in the next pregnancy. CONCLUSIONS: Anxiety related to a screen-positive result probably causes decreased participation in maternal serum screening in the next pregnancy. Reducing the screen-positive rate in prenatal serum screening would alleviate maternal anxiety and would probably lead to more stable participation. Luks FI. Requirements for fetal surgery: the diaphragmatic hernia model. European Journal of Obstetrics, Gynecology, & Reproductive Biology. 92(1):115-8, 2000 Sep. Abstract Fetal surgery for congenital diaphragmatic hernia and other fetal conditions can only be considered if (1) the morbidity of antenatal intervention is acceptable, (2) the diagnosis of the condition can be made accurately, (3) the condition can be differentiated from other, non-surgical anomalies. In addition, (4) the natural evolution of the disease, if left untreated, should be predictable, and the condition should be lethal or severely debilitating, (5) there should not exist adequate postnatal treatment, and (6) the proposed in utero operation should be technically feasible. Open fetal surgery has proven too invasive to be justified for the treatment of diaphragmatic hernia, and progress in postnatal therapy (including ECMO) has dramatically improved the neonatal outcome in all but a severe subgroup of patients. Recently, advances in endoscopic fetal surgery (which appears to be less stressful for the fetus and the gravid uterus) and a new approach to accelerate fetal lung growth and maturation have renewed the feasibility of in utero intervention for diaphragmatic hernia. [References: 59]   Ervin MG. Padbury JF. Polk DH. Ikegami M. Berry LM. Jobe AH. Antenatal glucocorticoids alter premature newborn lamb neuroendocrine and endocrine responses to hypoxia. American Journal of Physiology - Regulatory Integrative & Comparative Physiology. 279(3):R830-8, 2000 Sep. Abstract Glucocorticoids are administered for preterm labor to improve postnatal adaptation. We assessed the effect of antenatal betamethasone (Beta) treatment on preterm newborn lamb neuroendocrine [catecholamine, arginine vasopressin (AVP)] and endocrine [triiodothyronine (T(3)), ANG II, and atrial natriuretic factor (ANF)] adaptive responses following delivery and a hypoxic challenge. Beta treatment included direct fetal injection at 0.2 (F(0.2); n = 8) or 0.5 (F(0.5); n = 7) mg/kg estimated fetal body weight or maternal injection with 0.2 (n = 8) or 0.5 mg/kg (M(0.5); n = 8). Control animals received fetal and maternal intramuscular injections of saline (n = 8). After 24 h, lambs were delivered by cesarean section, surfactant treated, and ventilated for 4 h. Relative to the control lambs, 3 h after delivery, there was a marked suppression of plasma cortisol, epinephrine, norepinephrine, and ANG II levels and elevated plasma T(3) and ANF levels, systolic blood pressure, and left ventricular contractility (dP/dt; F(0.5) and M(0.5)) values in F(0.5) and both maternal Beta-treated groups. However, Beta treatment augmented the cardiac output, cortisol, norepinephrine, AVP, and ANF responses to 20 min of hypoxia (PO(2) = 25-30 mmHg). We concluded that short-term (24 h) antenatal glucocorticoid exposure 1) alters preterm newborn postnatal blood pressure regulation in the face of marked depression of plasma cortisol, catecholamine, and ANG II levels and 2) augments the postnatal neuroendocrine and endocrine responses to a hypoxic challenge. Rehan VK. Nakashima JM. Gutman A. Rubin LP. McCool FD. Effects of the supine and prone position on diaphragm thickness in healthy term infants. Archives of Disease in Childhood. 83(3):234-8, 2000 Sep. Abstract BACKGROUND: The physiological basis underlying the decline in the incidence of sudden infant death syndrome (SIDS) associated with changing the sleep position from prone to supine remains unknown. AIMS: To evaluate diaphragm thickness (t(di)) and shortening in healthy term infants in the prone and supine positions in order to determine whether changes in body position would affect diaphragm resting length and the degree of diaphragm shortening during inspiration. METHODS: In 16 healthy term infants, diaphragm thickness at the level of the zone of apposition on the right side was measured using ultrasonography. Heart rate (HR), breathing frequency (f), and transcutaneous oxyhaemoglobin saturation (SaO(2)) were recorded simultaneously during diaphragm imaging with the infants in the supine and prone positions during quiet sleep. RESULTS: At end expiratory (EEV) and at end inspiratory lung volumes (EIV), t(di) increased significantly in the prone position. The change in t(di) during tidal breathing was also greater when the infant was prone. SaO(2), HR, and f were not significantly different at EEV and at EIV in both positions. CONCLUSION: In healthy term infants, placed in the prone position, the diaphragm is significantly thicker and, therefore, shorter, both at EEV and EIV. Diaphragm shortening during tidal breathing is greater when the infant is prone. In the prone position, the decreased diaphragm resting length would impair diaphragm strength, and the additional diaphragm shortening during tidal breathing represents added work performed by the diaphragm. This may compromise an infant's capacity to respond to stressful situations when placed in the prone position and may contribute to the association of SIDS with prone position. Lambert-Messerlian GM. Palomaki GE. Canick JA. Second trimester levels of maternal serum inhibin A in pregnancies affected by fetal neural tube defects. Prenatal Diagnosis. 20(8):680-2, 2000 Aug. Abstract Inhibin A is effective as a second trimester maternal serum marker for Down syndrome screening. In the present study, inhibin A levels were measured in second trimester maternal serum samples from 28 pregnancies affected with open neural tube defects; 12 associated with open spina bifida and 16 associated with anencephaly. Each measurement was expressed as a multiple of the median (MoM) for control singleton pregnancies (n=1464) of the same completed week of gestation. Inhibin A levels were not significantly altered in cases of open neural tube defects; the median value was 0.96 MoM in cases of open spina bifida and 1.19 MoM in cases of anencephaly. Therefore, second trimester maternal serum inhibin A levels will not have an impact on prenatal detection of open neural tube defects. Copyright 2000 John Wiley & Sons, Ltd. Luks FI. Wild YK. Piasecki GJ. De Paepe ME. Short-term tracheal occlusion corrects pulmonary vascular anomalies in the fetal lamb with diaphragmatic hernia. Surgery. 128(2):266-72, 2000 Aug. Abstract BACKGROUND: Sustained fetal tracheal occlusion (TO) results in accelerated lung growth but causes severe type II cell depletion. Temporary TO fails to cause lung growth in a congenital diaphragmatic hernia (CDH) model but preserves type II cells and corrects pulmonary hypertension. Herein, we study the pulmonary vascular changes caused by temporary TO. METHODS: CDH was created in 12 fetal lambs (65-70 d; term, 145 days). In 6 lambs, the trachea was occluded for 2 weeks (CDH + TO; 108-122 d). Animals were killed at 136 days. The lungs were processed with elastin stains and anti-alpha-smooth muscle actin antibody. Partial or circumferential presence of inner and outer elastic lamina was used to determine muscularization of pulmonary arterioles. The percent of medial wall thickness was plotted against vessel diameter for each group. RESULTS: Lung weight/body weight was smaller in lambs with CDH (1. 35% +/- 0.56%) and CDH + TO (1.70% +/- 0.34%) than in control lambs (3.55% +/- 0.56%; P <.05, single-factor analysis of variance). The smallest muscularized vessel was 113 +/- 50 microm, and the largest nonmuscularized vessel was 138 +/- 49 microm in lambs with CDH, significantly different from control lambs (185 +/- 69 microm and 350 +/- 116 microm, respectively) and lambs with CDH + TO (185 +/- 97 microm and 245 +/- 100 microm, respectively; P <.05). In lambs with CDH, only 25% of vessels of less than 60 microm were nonmuscularized, compared with 81% in control lambs (P <.05) and 74% in lambs with CDH + TO.Conclusions. Temporary tracheal occlusion, from 108 to 122 days, corrects the abnormal muscularization of pulmonary arterioles seen in CDH. These morphometric findings parallel physiologic results at birth and further suggest that short-term occlusion, which preserves surfactant-producing type II pneumocytes without lung growth, may be sufficient to improve neonatal outcome of diaphragmatic hernia.   Stonestreet BS. Sadowska GB. McKnight AJ. Patlak C. Petersson KH. Exogenous and endogenous corticosteroids modulate blood-brain barrier development in the ovine fetus. American Journal of Physiology - Regulatory Integrative & Comparative Physiology. 279(2):R468-77, 2000 Aug. Abstract We previously reported decreases in blood-brain barrier permeability in the ovine fetus at 80% of gestation after antenatal corticosteroids and shown that permeability is not reduced in newborn lambs after postnatal corticosteroids. We now test the hypotheses that exogenous antenatal corticosteroids decrease blood-brain barrier permeability at 60% but not 90% of gestation in ovine fetuses and that endogenous increases in plasma cortisol concentrations are associated with ontogenic decreases in barrier permeability during gestation. Chronically instrumented ovine fetuses were studied 12 h after the last of four 6-mg dexamethasone or placebo injections were given 12 h apart over 48 h to ewes. Fetuses at 80% of gestation from placebo-treated ewes studied under the same protocol were also included. Blood-brain barrier function was quantified with the blood-to-brain transfer constant (K(i)) to alpha-aminoisobutyric acid. K(i) values were lower in cerebral cortex, caudate nucleus, hippocampus, superior colliculus, thalamus, medulla, and cervical spinal cord in fetuses of dexamethasone- than placebo-treated ewes at 60% but not 90% of gestation. Regional brain K(i) values demonstrated inverse correlations with increases in gestation and plasma cortisol concentrations in most brain regions. We conclude that maternal treatment with exogenous corticosteroids was associated with decreases in blood-brain barrier permeability at 60% but not 90% of gestation and that increases in gestation and endogenous cortisol concentrations were associated with ontogenic decreases in barrier permeability during fetal development. Dexter SC. Pinar H. Malee MP. Hogan J. Carpenter MW. Vohr BR. Outcome of very low birth weight infants with histopathologic chorioamnionitis. Obstetrics & Gynecology. 96(2):172-7, 2000 Aug. Abstract OBJECTIVE: To determine neonatal outcome at 7 months of corrected age in very low birth weight (VLBW) infants with placental chorioamnionitis. METHODS: We conducted a cohort study of 287 VLBW infants delivered as a result of preterm premature rupture of membranes (PROM) or preterm labor. Control subjects (n = 123) had placentas with absent umbilical cord inflammation and absent or low-grade membrane inflammation. Case subjects (n = 164) had moderate membrane inflammation or any umbilical cord inflammation. Neonatal and 7-month outcomes were compared. A power analysis showed that 98 total subjects were needed to reject the two-sided null hypothesis with a difference in mean Bayley index scores of at least 8. RESULTS: Infants in the study group had significantly more preterm PROM, antenatal antibiotics, lower birth weight, lower gestational age, longer duration of ruptured membranes, and clinical chorioamnionitis. Intraventricular hemorrhage occurred more commonly in infants with placentas demonstrating chorioamnionitis (relative risk = 1.6, 95% confidence interval 1.1, 2.4, P =.013). One hundred sixty-seven (69%) of the 243 surviving infants had 7-month follow-up. There was no difference between cases and controls in mean Bayley mental developmental index (93 compared with 90, P =.25), psychomotor developmental index (89 compared with 90, P =.68), or in the number of infants that were developmentally delayed. CONCLUSION: Despite a higher frequency of intraventricular hemorrhage, no difference in developmental scores was detected at 7 months of corrected age in VLBW infants with histologic chorioamnionitis. Msall ME. Tremont MR. Functional outcomes in self-care, mobility, communication, and learning in extremely low-birth weight infants. Clinics in Perinatology. 27(2):381-401, 2000 Jun. Abstract Gaps have existed in specifying degrees of severity of cerebral palsy assessment of self-care and communicative competencies, and specifying age-appropriate preschool educational and behavioral competencies. Imbedded in the concept of measuring functional status is the interaction between health and neurologic impairments, developmental challenges and competencies, family resources and disadvantages, and the child's current status. In reviewing historic outcomes of severe ROP over the past 40 years, it was noted that severe ROP caused blindness in 2% to 11% of survivors. There was a constant observation that approximately 50% of severe ROP survivors with blindness had multiple functional and developmental challenges beyond blindness alone. Similarly, in reviewing outcomes of cerebral palsy, it is imperative to describe the severity of cerebral palsy and functional consequences in motor, selfcare, communication, and learning. The reason to measure the functional status of children with neurodevelopmental impairments before first grade is that the degrees of severity of these disorders can be specified before attending school with peers. Subtler aspects of neurodevelopmental impairments need to assess impact on literacy, information learning, written language, social competencies with peers, and recreational and community participation. In this way, we can understand the vulnerabilities and resiliences of children and families of VLBW and ELBW status. This is a critical step in understanding long-term quality of life and independent living issues. In addition, our efforts can address those factors and pathways whereby multiple disabilities and multiple functional limitations cluster. Our biomedical intervention can prioritize strategies that lessen severe multiple disabilities and simultaneously support families, when despite our best efforts functional challenges are life long. [References: 74] Lambert-Messerlian GM. Silver HM. Petraglia F. Luisi S. Pezzani I. Maybruck WM. Hogge WA. Hanley-Yanez K. Roberts JM. Neveux LM. Canick JA. Second-trimester levels of maternal serum human chorionic gonadotropin and inhibin a as predictors of preeclampsia in the third trimester of pregnancy. Journal of the Society for Gynecologic Investigation. 7(3):170-4, 2000 May-Jun. Abstract OBJECTIVE: To determine whether second-trimester maternal serum levels of inhibin A, human chorionic gonadotropin (hCG), unconjugated estriol (uE3), and alpha-fetoprotein (AFP) are predictive of the later onset of preeclampsia in pregnancy. METHODS: Retrospective evaluation of serum analyte levels in 60 women with preeclampsia compared with 300 controls. Levels of each analyte were compared in women with preeclampsia and controls using matched rank analysis. Analytes that were significantly different between groups were examined with univariate and bivariate Gaussian distribution analysis. RESULTS: Second-trimester inhibin A (1.36 multiples of the median [MoM]) and hCG (1.40 MoM) levels were significantly but modestly elevated in women who later developed preeclampsia. A combination test of maternal age plus inhibin A and hCG predicted 23% of cases of preeclampsia with 95% specificity. There was a statistically significant trend for inhibin A, but not hCG, levels to be higher when the onset of preeclampsia occurred within a shorter (<17 weeks) interval after collection of the second-trimester screening sample. CONCLUSIONS: Second-trimester serum levels of inhibin A and hCG are modest predictors of the later onset of preeclampsia. Inhibin A may be a better predictor of early-onset preeclampsia, which is associated with a higher maternal and perinatal morbidity and mortality, than preeclampsia at or near term.   Liao SL. Luks FI. Piasecki GJ. Wild YK. Papadakis K. De Paepe ME. Late-gestation tracheal occlusion in the fetal lamb causes rapid lung growth with type II cell preservation. Journal of Surgical Research. 92(1):64-70, 2000 Jul. Abstract BACKGROUND: Fetal tracheal occlusion (TO) results in varying degrees of lung growth. This study examines whether gestational age influences lung growth response following TO. MATERIALS AND METHODS: Fetal lambs (term = 145 days) underwent TO early (108 days, n = 6) or late (122 days, n = 6) in gestation. Aspirated lung fluid volume (LFV) and intratracheal pressure (ITP) were recorded daily. Two weeks after TO, the fetuses were sacrificed. Lung growth was assessed by lung weight and stereologic volumetry. Type II cellular density was assessed by computer-assisted morphometry using antisurfactant protein B antibody. RESUTLS: After early TO, ITP remained below 2 mm Hg for all but one of the first 5 days. In late TO, ITP rose to 4.8 +/- 1.7 mm Hg by Day 1 and remained elevated. LFV remained lower after early than after late TO (P < 0.05) for 8 days. Thereafter, pressure and volume reached similar levels in both TO groups; both were significantly higher than their respective controls (P < 0.05). Parenchymal fraction (1 - air-space fraction) was significantly smaller after late TO (22.8 +/- 1.2%) than after early TO (31.3 +/- 0.5%). Type II density was 38.0 +/- 12.4 x 10(6)/mL after early TO and 84.0 +/- 24.3 x 10(6)/mL in control (P < 0.05); the difference between late TO and control was not significant. CONCLUSIONS: Late tracheal occlusion in fetal lambs caused more rapid lung growth than earlier TO, although ultimate lung size was similar in both groups. Late TO also resulted in greater air-space fraction and better preservation of the type II cell population than early TO. Late-gestation tracheal occlusion may therefore be preferable to prolonged occlusion initiated earlier. Copyright 2000 Academic Press.   Goldstein M. Rehan VK. Oh W. Stonestreet BS. Cerebral and intestinal perfusion and metabolism in normocythemic hyperviscous hypoxic newborn pigs. Journal of Applied Physiology. 88(6):2107-15, 2000 Jun. Abstract We studied the effects of hypoxia on cerebral cortical and intestinal perfusion and metabolism in normocythemic hyperviscous newborn pigs. Seven pigs were made hyperviscous by an injection of cryoprecipitate, increasing viscosity from 5.8 +/- 0.9 to 9.0 +/- 1. 2 (SD) cycles/s. Six normoviscous pigs received 0.9% NaCl. Reducing the inspired O(2) decreased the arterial O(2) content (Ca(O(2))) from 9.5 +/- 1.6 to 3.6 +/- 1.3 ml O(2)/100 ml. Increases in brain and decreases in gastrointestinal blood flow at the lower Ca(O(2)) values were similar between the groups. During hypoxia, blood flow to stomach, distal intestinal mucosa, and large intestines was lower (-50, -23, and -28%, respectively) in the hyperviscous than normoviscous group. At the lower Ca(O(2)) values, cerebral cortical vascular resistance decreased in both groups and intestinal vascular resistance increased (+257%) in the hyperviscous but not in the normoviscous group. During hypoxia, systemic oxygen delivery decreased, extraction increased, and uptake did not change; cerebral cortical O(2) delivery, extraction, and uptake did not change; and intestinal O(2) delivery decreased, extraction increased, and uptake did not change in both groups. Our study demonstrated that 1) during hypoxia, increases in systemic O(2) extraction compensated for decreases in delivery and systemic uptake did not change; vasodilation sustained cerebral cortical O(2) delivery and preserved metabolism; increases in intestinal oxygen extraction offset decreases in delivery and uptake was preserved; and 2) nonpolycythemic hyperviscosity did not have a major influence on cardiovascular or metabolic responses to hypoxia, except for modest effects on intestinal resistance and perfusion to certain gastrointestinal regions. We conclude that, under normocythemic conditions, a moderate increase in viscosity does not have a major impact on hemodynamic or metabolic adjustments to hypoxia in newborn pigs. Rausch DN. Lambert-Messerlian GM. Canick JA. Participation in maternal serum screening following screen positive results in a previous pregnancy. Journal of Medical Screening. 7(1):4-6, 2000. Abstract OBJECTIVE: To determine whether women who have had a positive serum screening result in one pregnancy have a lower rate of participation in screening in their next pregnancy. SETTING: The Women and Infants Hospital triple marker screening programme. METHODS: Pregnancy and screening information was collected from laboratory and hospital databases to compare subsequent screening participation in women who were screen negative and screen positive for risk of Down's syndrome (DS) or neural tube defect (NTD) pregnancy. RESULTS: In an age matched comparison, 108 women who had a previous screen positive result were significantly less likely than 108 women who were screen negative to participate in maternal serum screening in their next pregnancy. When examined according to type of screen positive result, the effect was significant for both those who were screen positive for DS and those who were screen positive for NTD. The degree of risk in screen positive women did not significantly affect their uptake of screening in the next pregnancy. CONCLUSIONS: Anxiety related to a screen positive result probably causes decreased participation in maternal serum screening in the next pregnancy. Reducing the screen positive rate in prenatal serum screening would alleviate maternal anxiety and would probably lead to more stable participation. Malee MP. Wu KY. Corticosteroid dynamics in the nonpregnant, pregnant, and postpartum spontaneously hypertensive rat. American Journal of Hypertension. 13(4 Pt 1):410-7, 2000 Apr. Abstract Factors responsible for hypertension in the spontaneously hypertensive rat (SHR) remain under investigation. As in human pregnancy complicated by essential chronic hypertension, the hypertension of the pregnant SHR subsides and returns postpartum. Because corticosteroid excess can cause hypertension, we examined several aspects of adrenocortical activity as potentially affecting the reported blood pressure profiles of nonpregnant, term pregnant, and postpartum SHR, using normotensive Wistar-Kyoto (WKY) rats as controls. We found that corticosterone levels were comparable in nonpregnant SHR and WKY rats, and unaffected by pregnancy. No differences were detected postpartum. Although pregnancy was accompanied by significant increases in plasma aldosterone levels, no interbreed differences were observed, which remained the case postpartum. Single adrenal cell secretion of aldosterone and corticosterone, as detected by reverse hemolytic plaque assay, yielded similar results in the pregnant and postpartum rat. Hormone responses to dietary manipulations in the nonpregnant and pregnant SHR and WKY suggest an important role for ACTH, and a lesser one for AII in the regulation of corticosteroids. In situ hybridization histochemistry, using a probe that detects both P450c11beta and P450c11AS mRNA, revealed comparable message density and zonal distribution in adrenals from pregnant and nonpregnant SHR and WKY rats. Breed- and pregnancy-dependent differences in adrenal expression of P450scc, P450c11beta, and P450c11AS were noted. In summary, our findings suggest that although some discrepancies exist in the aspects of adrenocortical activity examined, they are unlikely to be etiologic in the blood pressure profile observed in nonpregnant, pregnant, and postpartum SHR. Roggin KK. Breuer CK. Carr SR. Hansen K. Kurkchubasche AG. Wesselhoeft CW Jr. Tracy TF Jr. Luks FI. The unpredictable character of congenital cystic lung lesions. Journal of Pediatric Surgery. 35(5):801-5, 2000 May. Abstract BACKGROUND: The spectrum of congenital cystic disease of the lung ranges from hydrops and neonatal respiratory distress to asymptomatic lesions. Surgical management is dictated by the presence of symptoms, recurrent infection, and the potential risk of malignant transformation. METHODS: Since 1995, all consecutive patients with congenital cystic lung lesions underwent follow-up for symptoms, treatment, and correlation of presumptive with pathological diagnosis. RESULTS: Twelve cystic lung lesions were identified. Seven were diagnosed with mediastinal shift in utero; in 6 of 7, the shift subsequently resolved. Overall, 6 of 7 lesions that were followed up serially decreased in size. Two patients were symptomatic in utero; 1 underwent thoracoamniotic shunting, 1 pleurocentesis for impending hydrops. Postnatally, these 2, and 2 other newborns required urgent surgery. Five of 8 asymptomatic patients had elective resection by 16 months, and 4 await operation. In 6 of the 9 surgical cases (67%), there was a discrepancy between preoperative and pathological diagnosis. There were 4 hybrid congenital cystic adenomatoid malformation (CCAM)/sequestrations. CONCLUSIONS: At least 6 of 7 congenital cystic lung lesions decreased in size regardless of gestational age or presence of mediastinal shift. Antenatal intervention is therefore rarely indicated. Hybrid morphology may necessitate resection of stable, asymptomatic lesions to prevent the theoretical concern for associated malignancies as well as other complications of CCAM. Wild YK. Piasecki GJ. De Paepe ME. Luks FI. Short-term tracheal occlusion in fetal lambs with diaphragmatic hernia improves lung function, even in the absence of lung growth. Journal of Pediatric Surgery. 35(5):775-9, 2000 May. Abstract BACKGROUND/PURPOSE: Prolonged tracheal occlusion (TO) accelerates lung growth but impairs surfactant production. Short-term TO results in less lung growth but preserves type II cell function. The authors studied the effects of short-term TO on lung physiology in diaphragmatic hernia. METHODS: Diaphragmatic hernia was created in 9 fetal lambs at 90 to 95 days. Five were left uncorrected (CDH), 4 underwent 2-week TO (108 to 122 days; CDH + TO). Five unoperated lambs served as controls. Near-term (136 days) fetuses were ventilated for 90 to 150 minutes. Pulmonary arterial pressure, postductal blood gases, quasistatic compliance, total lung capacity (TLC), and lung weight to body weight (LW/BW) were measured. RESULTS: There was an overall survival rate of 89% at full term. Short-term occlusion did not induce lung growth (TLC and LW/BW, 6.07 +/- 2.92 mL/kg and 0.022 +/- 0.008 in CDH, 4.86 mL/kg and 0.019 +/- 0.005 in CDH + TO, 10.81 +/- 3.55 mL/kg and 0.036 +/- 0.006 in controls, respectively). However, pulmonary hypertension in CDH (47.4 +/- 12.32/35.8 +/- 12.19 torr) was corrected by short-term occlusion (20.2 +/- 4.0/16.0 +/- 4.8 torr in CDH + TO, P< .05, single-factor analysis of variance [ANOVA]; similar to control). Best pO2 and pCO2 improved after occlusion (CDH, 48.6 +/- 6.7 torr and 107.1 +/- 34.3 torr, respectively; CDH + TO, 101.5 +/- 16.3 torr and 81.9 +/- 2.4 torr; control, 291.4 +/- 4.7 torr and 37.7 +/- 17.3), as did oxygenation index (P < .05, CDH vCDH + TO; CDH, 97.2 +/- 23.0; CDH + TO, 28.7 +/- 3.1; control, 5.6 +/- 0.6). CONCLUSIONS: Short-term TO corrects pulmonary hypertension and improves gas exchange in fetal lambs with diaphragmatic hernia despite failure to produce accelerated lung growth. Inducing lung maturation and correcting the physiological derangement in diaphragmatic hernia may be more important than achieving lung growth alone. Stonestreet BS. McKnight AJ. Sadowska G. Petersson KH. Oen JM. Patlak CS. Effects of duration of positive-pressure ventilation on blood-brain barrier function in premature lambs. Journal of Applied Physiology. 88(5):1672-7, 2000 May. Abstract We have been studying the ontogeny of the blood-brain barrier function in ovine fetuses and lambs. During these studies, we have found that the duration of ventilation also influences blood-brain barrier permeability in premature lambs. Chronically instrumented hysterotomy-delivered surfactant-treated premature lambs were studied at 90% or 137 days of gestation (n = 9). Blood-brain barrier function was quantified with the blood-to-brain transfer constant K(i) to alpha-aminoisobutyric acid. Linear regression analysis was used to compare the K(i) values in the brain regions, as the dependent variable, to the duration of ventilation, as the independent variable. There were direct correlations (P < 0.05) between the K(i) values and the duration of ventilation [306 min (mean), 162-474 min (range)] in the cerebral cortex, cerebellum, medulla, caudate nucleus, hippocampus, superior colliculus, inferior colliculus, thalamus, pons, cervical spinal cord, and choroid plexus, but not in the pituitary gland. Ventilatory pressures and rates were established before the onset of the permeability studies. Calculated mean airway pressures [14 cmH(2)O (mean), 7-20 cmH(2)O (range)] from similarly studied premature lambs did not correlate with the duration of positive-pressure ventilation. We conclude that increases in the duration of positive-pressure ventilation predispose premature lambs to increases in regional blood-brain barrier permeability. These alterations in barrier function occur over relatively short time intervals (minutes to hours). In our study, these changes in permeability are most likely not attributable to changes in mean airway pressure. Hanna N. Hanna I. Hleb M. Wagner E. Dougherty J. Balkundi D. Padbury J. Sharma S. Gestational age-dependent expression of IL-10 and its receptor in human placental tissues and isolated cytotrophoblasts. Journal of Immunology. 164(11):5721-8, 2000 Jun 1. Abstract Control of antifetal immune responses is thought to be regulated locally by the placenta. Because the physiologic programming of the placenta across gestation is likely to influence the local immunity, we hypothesize that a potent anti-inflammatory cytokine such as IL-10 may be produced in a gestational age-dependent manner. In the present study, we examined the expression of IL-10 and its receptor in placental explants or freshly isolated cytotrophoblasts from different gestational ages and compared it with the expression profiles of other cytokines. First and second trimester placental tissues from normal pregnancies predominantly expressed IL-10, whereas the levels of IL-2, IL-4, and IFN-gamma were mostly below detection throughout pregnancy. The expression of IL-10, but not its receptor, diminished significantly in term placental tissues collected "before" the onset of labor and did not change appreciably "after" labor. On the other hand, TNF-alpha and IL-1beta were significantly up-regulated in response to labor-associated conditions. IL-10 expression was transcriptionally attenuated at term as observed in cytotrophoblasts. In contrast to the placental cytokine milieu, autologous PBMCs, when activated with PHA, secreted significant amounts of IL-2, IL-4, IL-10, and IFN-gamma, albeit with a statistically significantly enhanced IL-10 production in first trimester compared with age-matched nonpregnant women. These data suggest that IL-10 is expressed in the placenta in a gestational age-dependent manner and that its down-regulation at term may be an important mechanism underlying the subtle changes associated with parturition. Oyer CE. Feit LR. Rogers BB. Kuhn C. In utero development of hypertensive necrotizing pulmonary arterial lesions: report of a case associated with premature closure of the ductus arteriosus and pulmonary hypoplasia. Cardiovascular Pathology. 9(1):39-47, 2000 Jan-Feb. Abstract Premature closure of the ductus arteriosus (PCDA) is an uncommon defect in which pulmonary hypertension (PH) has been documented by echocardiography in patients and by direct measurement after experimental PCDA in animals. The pulmonary vascular histology in human cases has received little attention but in the few recorded observations the vessels were either normal or showed increased muscularity. We report the case of a 31 week hydropic female stillborn monozygotic twin in whom postmortem examination disclosed PCDA and hypoplasia of the lungs. Atypical plexiform lesions with necrotizing pulmonary arteritis were present. These lesions represent vascular consequences of severe pulmonary hypertension produced by greatly enhanced blood flow through a restricted vascular bed resulting from the combined effects of these two abnormalities. The findings in this case of PCDA with presumed severe PH indicate that severe pulmonary vascular changes can develop in utero and that the interval of time needed for development of such chances in secondary PH is relatively short. Malone FD. Berkowitz RL. Canick JA. D'Alton ME. First-trimester screening for aneuploidy: research or standard of care? American Journal of Obstetrics & Gynecology. 182(3):490-6, 2000 Mar. Abstract First-trimester screening for Down syndrome has been proposed as a significant improvement with respect to second-trimester serum screening programs, the current standard of care, because of apparently higher detection rates and an earlier gestational age at diagnosis. First-trimester nuchal translucency on ultrasonography forms the basis of this new form of screening, although studies of its efficacy have yielded widely conflicting results, with detection rates ranging from 29% to 91%. Studies of first-trimester serum screening with measurements of pregnancy-associated plasma protein A and free beta-human chorionic gonadotropin serum concentrations have been much more consistent, with Down syndrome detection rates of 55% to 63% at a 5% false-positive rate. The combination of first-trimester ultrasonographic and serum screening has the potential to yield a Down syndrome detection rate of 80% at a 5% false-positive rate, although this approach has not been adequately studied. There have been no studies performed to date to directly compare the performance of first-trimester and second-trimester methods of screening. Two major trials are underway that will address this issue, one in the United Kingdom and one in the United States. Until the results of these trials are available, the current standard of care with respect to Down syndrome screening should not be changed, and first-trimester screening should remain investigational. [References: 40]   Phipps MG. Hogan JW. Peipert JF. Lambert-Messerlian GM. Canick JA. Seifer DB. Progesterone, inhibin, and hCG multiple marker strategy to differentiate viable from nonviable pregnancies. Obstetrics & Gynecology. 95(2):227-31, 2000 Feb. Abstract OBJECTIVE: To determine whether a combination of serum and urine biomarkers drawn from symptomatic pregnant women will help early differentiation of viable from nonviable pregnancies. METHODS: We conducted a prospective cohort study of 220 women who presented in the first trimester of pregnancy with complaints of pain, cramping, bleeding, or spotting. Serum samples for progesterone, inhibin A, and hCG, and urine beta-core hCG, were collected at presentation. To evaluate whether those biomarkers could predict viable and nonviable outcomes in pregnancy, we used likelihood ratios to compare operating characteristics of single and multiple biomarker strategies. RESULTS: Of 220 pregnancies studied, 98 were viable and 122 nonviable. Among single biomarkers, progesterone alone appears to have the greatest utility (area under the receiver operator characteristic curve = 0.923). Among dual-biomarker strategies, progesterone plus hCG and progesterone plus inhibin A improved specificity but not sensitivity. At 95% sensitivity, the combination of progesterone and hCG improved specificity from 0.29 to 0.66 (improvement = 0.37 [95% confidence interval 0.23, 0.52]). A triple-biomarker combination did not show substantial improvement over the dual-biomarker strategy. Also, combinations that used urine beta-core hCG did not improve diagnostic accuracy. CONCLUSION: Serum progesterone appeared to be the single most specific biomarker for distinguishing viable from nonviable pregnancies. When a dual-biomarker strategy was applied, combining serum progesterone with hCG, specificity improved significantly, which suggests that a multiple biomarker strategy might help distinguish viable from nonviable pregnancies in early gestation. Malee MP. Wu KY. Adrenocortical activity in fetal SHR and WKY rats. Pediatric Research. 47(1):143-7, 2000 Jan. Abstract There is increasing evidence that the intrauterine milieu and corticosteroid exposure play a role in the etiology of hypertension. We examined adrenocortical gene expression and circulating corticosteroids in the d 21 fetal spontaneously hypertensive rat (SHR) and its normotensive genetic control, the Wistar-Kyoto (WKY) rat. By RNase protection assays, we found no differences in the relative abundances of mRNAs for P450scc and P450c11beta, and barely detectable P450c11AS mRNA in the adrenals of fetal SHR and WKY rats. P450c11B3 RNA was undetectable by reverse transcription polymerase chain reaction in both SHR and WKY fetuses. The zonal expression of P450c11 mRNA was comparable in SHR and WKY fetuses by in situ hybridization histochemistry. There were no significant differences in peripheral levels of aldosterone and corticosterone by radioimmunoassay in fetal SHR and WKY rats. Based upon the absence of distinct differences in the aspects of adrenocortical activity examined, it is unlikely that they are integral in the programming of hypertension in this model. Pinar H. Pinar T. Singer DB. Beta-cell hyperplasia in macrosomic infants and fetuses of nondiabetic mothers. Pediatric & Developmental Pathology. 3(1):48-52, 2000 Jan-Feb. Abstract The objective of this study was to test the hypothesis that macrosomic infants of nondiabetic mothers have beta-cell hyperplasia in their pancreases. Pancreatic tissues were examined from 10 macrosomic fetuses and liveborn infants and from 10 comparison cases matched for gestational age and gender. None of the mothers had a history of diabetes and all had normal glucose screening during pregnancy. Tissues were stained with hematoxylin and eosin and a monoclonal antibody against beta cells and were analyzed using an image analysis program to evaluate the size and surface area of beta-cell clusters. Brain/liver weight ratios were calculated and compared. The total surface area and cluster size of beta cells in the pancreases of macrosomic subjects were significantly larger than in the comparison pancreases. The study subjects lacked macroscopic and histopathologic findings expected in infants of diabetic mothers. We conclude that some macrosomic fetuses and infants of nondiabetic mothers manifest beta-cell hyperplasia. This corresponds to the higher insulin levels in macrosomic infants of nondiabetic mothers described in previous clinical studies. In macrosomic fetuses the stimulus for beta-cell hyperplasia may not involve aberrant maternal glucose levels.

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