bluuebunny/crossref_metadata_2025 huggingface dataset:
Age-Related Differences in the Glomerular and Renal Tubular Effects of Amikacin in the Rat
Authors: Meléndez Estela , López Miriam , López Carolina , Reyes José Luis
Published: October 2009

Several biological responses to drugs are dependent on the age of the individual. Renal excretion of amikacin occurs mainly through glomerular filtration and this function is diminished in the young animal. We evaluated the renal response to amikacin in the unanesthetized infant rat (21-day-old) and we compared it with that of the adult rat. Either amikacin (7.5 and 75.0 mg/kg body weight, i.m.) or vehicle were administered to infant rats and the effects on sodium, potassium and water balance were assessed. Creatinine clearance (Ccr) was calculated. Amikacin induced an increment in sodium absolute excretion, whereas the Ccr decreased. In the infant rat the effects were more marked. Chang es in FENa were more marked than those in Ccr, suggesting a direct effect of amikacin on the tubular reabsorption of electrolytes in addition to deleterious effects on glomerular dynamics. Our results suggest that amikacin induces more changes in renal function in the infant than in the adult rat and therefore it might be convenient to carefully evaluate the renal condition in the patients that receive this drug.
Erythroblastopenia Associated with Methylmalonic Aciduria
Authors: Corazza F. , Blum D. , Clercx A. , Mardens Y. , Fondu P.
Published: October 2009

Various cytopenias, including neutropenia, thrombocytopenia and pancytopenia, have been reported in association with inborn errors of branched amino acid metabolism. We report here on a case of anemia associated with erythroblastopenia – that is less frequent in this context – in a neonate with methylmalonic aciduria. We used a semisolid erythroid culture system to investigate the effect on in vitro erythropoiesis of organic acids found in excess in this patient: methylmalonic (MMA) and propionic (PA) acids. First, the addition of 10% serum of the patient to a normal bone marrow progenitor culture suppressed the erythrocyte colony-forming unit growth in comparison to a pool of normal serum, while the addition of a 1:1 mixture of normal and patient serum resulted in an intermediate inhibition. MMA, when added to culture medium, resulted in a moderate inhibition of erythropoiesis only at a higher concentration than observed in our patient or reported in other cases. Conversely, PA showed an inhibitory effect at a concentration commonly observed in methylmalonic aciduria. The same effect was observed when the cells were in the presence of PA only for 72 h and then secondly plated in semi-solid culture. Neither MMA nor PA showed any effect on the cell number and viability after a 3-, 4- or 7-day incubation except at the highest concentration tested.
Platelet Activation in Newborns Detected by Flow-Cytometry
Authors: Gatti Loredana , Guarneri Daniela , Caccamo Maria Letizia , Gianotti Gian Angelo , Marini Antonio
Published: October 2009

Platelet function was investigated in full-term infants on the first, the fourth and the tenth days of life and compared to normal adult controls. Platelet function was analyzed through a new cytofluorimetric technique with two murine monoclonal antibodies, PAC-1 and anti-GMP-140, directed against two membrane proteins expressed on the activated platelets’ surface. The percentage of activated platelets detected with PAC-1 and anti-GMP-140 was evaluated at basal condition and after in vitro stimulation with a weak agonist (ADP) and a strong Txa2 analogue inducer (U 46619). At day 1 platelet activation at basal condition was negligible and similar to adult controls both with PAC-1 (1.2 vs. 1.1%) and anti-GMP-140 (2.6 vs. 3.3%). On the contrary, after ADP stimulation the percentage of PAC-1-positive activated platelets was significantly reduced in neonates compared to adults (22 vs. 66%; p < 0.001) and even more after U 46619 (11 vs. 72%; p < 0.001). The percentage of anti-GMP-140-positive activated platelets behaved similarly after adding both ADP (26 vs. 46%; p < 0.01) and U 46619 (37 vs. 67%; p < 0.001). The reduced platelet activation after ADP and U 46619 persisted at day 4 both with PAC-1 and with anti-GMP-140. On the contrary, at day 10 newborn platelets analyzed with anti-GMP-140 behaved similarly to the adult ones both at basal condition and after stimulation with ADP or U 46619 (6 vs. 3% at basal state, 42 vs. 46% after ADP addition, and 55 vs. 67% after U 46619). These data demonstrate that the reduced platelet activation present in newborns is restored by the tenth day after birth.
Effects of Colostrum Feeding on Intestinal Development in Newborn Pigs
Authors: Wang Tian , Xu Ruo-Jun
Published: October 2009

To investigate what factors lead to rapid postnatal tissue growth and functional maturation in the newborn intestine, we compared intestinal tissue mass and digestive enzyme activities between newborn unsuckled piglets and piglets bottle fed for 3 days with either 5% lactose solution, intact porcine colostrum or trypsinized porcine colostrum. Bottle feeding of colostrum or trypsinized colostrum, but not lactose solution, led to a significant increase in the weight and length of the small intestine (p < 0.01) and a significant increase in the mucosal weight of the large intestine (p < 0.05). The mucosal protein content in the small and large intestine and the mucosal DNA content in the large intestine increased significantly following 3 days of bottle feeding of porcine colostrum or trypsinized colostrum. The total mucosal DNA contents in the small intestine of piglets fed colostrum or trypsinized colostrum were, respectively, 39 and 64% greater than that in the newborn unsuckled piglets. Intestinal digestive enzymes showed a differential response to the dietary treatment. Bottle feeding of intact porcine colostrum, but not trypsinized porcine colostrum led to a significant increase in lactase- and alkaline phosphatase-specific activities in the small intestine, while bottle feeding of lactose solution led to a significant decrease in the specific activity of lactase. In contrast, the specific activity of maltase in the small intestine increased significantly with age irrespective of dietary treatment. These results indicate that genetic and dietary factors are involved in regulating postnatal intestinal development, and porcine colostrum contains a trypsin-labile component which can increase lactase and alkaline phosphatase activities in the newborn intestine.
Improved Recovery from Laryngeal-Stimulation-lnduced Apnea by Alpha-Adrenergic Blockade in Adult Rabbits
Authors: Beyaert C. , Haouzi P. , Marchal F.
Published: October 2009

The apnea triggered by laryngeal stimulation (LS) is associated with a redistribution of blood flow towards the heart and the brain that depends upon peripheral vasoconstriction. The circulatory component of the response to LS has been shown to be reduced following injection of large dose of β-adrenergic agonist that more intriguingly blunted the ventilatory response as well. To test whether the reduction of LS-induced apnea could be related to the decreased magnitude of the peripheral vasoconstriction, the effects of the α-adrenergic antagonist urapidil on the ventilatory and blood pressure responses to LS were studied in 6 adult rabbits. α-Adrenergic blockade reduced both the rise in blood pressure and the magnitude of hypopnea induced by LS. These results suggest that the circulatory component of the laryngeal chemoreflex, i.e. the peripheral vasoconstriction, contributes to the magnitude of the ventilatory depression.
Collagen and Glycosaminoglycans of Wharton’s Jelly
Authors: Sobolewski Krzysztof , Bańkowski Edward , Chyczewski Lech , Jaworski Stefan
Published: October 2009

In this study, we report quantity, solubility and molecular polymorphism of collagen, proportional relationships between various types of collagen, ultrastructure of collagen fibres, the amounts of various glycosaminoglycans (GAGs) and proportional relationships between them in Wharton’s jelly of normal umbilical cords. We compare the extracellular matrix components in Wharton’s jelly with those in the umbilical cord artery. Collagen of the Wharton’s jelly demonstrates some specific features. It is very insoluble in neutral salt and in a slightly acidic solution and appears to be resistant to the action of depolymerizing agent (EDTA-Na2). Only 50% of total collagen may be solubilized by pepsin digestion and fractionated by differential salt precipitation. Four collagen fractions were obtained. Three of them were identified by polyacrylamide gel electrophoresis as type I, type III, and type V collagen and proportional relationship between them was calculated. Hyaluronic acid is the most abundant component of GAGs contained in Wharton’s jelly. The amounts of sulphated GAGs – keratan sulphate, heparan sulphate, chondroitin-4-sulphate, chondroitin-6-sulphate, dermatan sulphate and heparin – are distinctly lower. Each of them constitutes only a few percent of total GAGs.
Relationship between Intrauterine Growth Retardation and Early Postnatal Superior Mesenteric Artery Blood Flow Velocity
Authors: Martinussen Marit , Brubakk Ann-Mari , Vik Torstein , Yao Alice C.
Published: October 2009

During the first week of life, we examined the changes in the systemic, intestinal and cerebral circulation, and the circulatory responses to feeding in 10 small for gestational age (SGA) infants using the ultrasound Doppler technique. From day 1 to day 3, preprandial cardiac output decreased (p < 0.01), whereas mean blood pressure (p < 0.01), superior mesenteric artery mean flow velocity (Vmean; p < 0.01) and middle cerebral artery Vmean (p < 0.01) increased. On day 1, cardiac output was higher in the SGA than in those of term and preterm appropriate for gestational age infants reported from our laboratory. Preprandial superior mesenteric artery Vmean was inversely related to the degree of growth retardation (r = 0.63, p < 0.05). However, growth retardation did not influence the postprandial increase in superior mesenteric artery Vmean and end-diastolic flow velocity, or the cerebral circulation.
Salt Supplementation, Growth, and Nephrocalcinosis in the Furosemide-Treated Weanling Rat
Authors: Gratny Linda L. , Ringer Kimberly , Hall Robert T. , Alon Uri S.
Published: October 2009

Objective: Furosemide treatment in the human neonate is associated with sodium depletion, growth retardation, hypercalciuria and nephrocalcinosis. Dietary sodium intake is known to directly influence urinary calcium excretion. The objectives of this study were to create a rat model of furosemide-induced nephrocalcinosis and to test the effects of dietary sodium supplementation on growth, electrolyte balance, calciuria, and renal calcifications. Methods: Initially, 18 weanling Sprague-Dawley rats were randomly divided into three groups. Groups A (control) and B were fed a basal diet. Group C was fed a sodium-enriched diet. Groups B and C received furosemide (40 mg/kg) intraperitoneally daily for 28 days. At the end of the study, serum, urine, and kidney samples were obtained for biochemical and histologic analyses. The three groups were then compared for differences in growth, electrolyte homeostasis, calcium excretion and nephrocalcinosis. Subsequently an additional 15 rats were studied to confirm our findings regarding urinary calcium excretion and kidney calcifications. Results: Treatment with furosemide without sodium supplementation (group B) resulted in decreased weight gain compared with group A (137.5 ± 12.9 vs. 154.0 ± 10.6 g; p < 0.05), hypokalemia (3.7 ± 0.1 vs. 4.4 ± 0.4mEq/l; p < 0.05), and nephrocalcinosis(187.1 ± 155 vs. 18.8 ± 6.9 µg Ca/g dry kidney; p < 0.05). Sodium supplementation (group C) normalized weight gain and corrected electrolyte abnormalities without increasing calciuria or nephrocalcinosis. Conclusions: We conclude that in this animal model, chronic furosemide treatment results in growth failure and development of nephrocalcinosis. Sodium supplementation protects against the deleterious effects of furosemide on weight gain and electrolyte homeostasis with no adverse effect on nephrocalcinosis.
Whole Body Lean Mass Is Altered by Dexamethasone Treatment through Reductions in Protein and Energy Utilization in Piglets
Authors: Weiler Hope A. , Wang Zheng , Atkinson Stephanie A.
Published: October 2009

The objective of this study was to assess the effect of dexamethasone on growth, body composition and protein metabolism using the piglet as a model for rapidly growing premature infants. Seven-day-old male pigs (n = 18) were randomized to 0.5 mg/kg/day oral dexamethasone or placebo for 15 consecutive days. Weight and length gains and weight gained per energy or protein consumed were significantly lower in the dexamethasone group. Serum urea nitrogen was significantly higher in the dexamethasone group by day 15 of the study. No differences were observed between groups for urinary creatinine. The whole body percent lean mass was significantly lower and percent fat mass was significantly higher in the dexamethasone piglets, as measured by dual energy X-ray absorptiometry. In young piglets, dexamethasone, at doses similar to those in premature infants, induces protein catabolism, impairs growth and alters its composition.
In vitro Regulation of Insulin Release and Biosynthesis of Fetal Rat Pancreatic Cells Explanted on Pregnancy Day 16
Authors: Aoyagi Kazumi , Bergsten Peter , Eriksson Ulf J. , Ebendal Ted , Hellerström Claes
Published: October 2009

Although the morphological development of the fetal pancreatic B cell has been studied in considerable detail, knowledge about the functional maturation, particularly in early stages of development, is still poor. The present paper describes a method for monolayer culture of fetal rat islet cells which allows a study of the regulation of insulin biosynthesis, release and content during critical stages of embryonic and fetal development. Suspensions of pancreatic cells were prepared from rat fetuses on pregnancy day 16 and cultured for 3 days. During the initial 2 days cultures were performed in the presence of 5 or 15 mmol/l glucose. During this initial period, culture at 5 mmol/l glucose was carried out in the presence or absence of either 10 mmol/l nicotinamide (NA) or 5 or 100 ng/ml nerve growth factor (NGF). After changing the media the cells were further exposed for 24 h to either 5 or 15 mmol/l glucose or 15 mmol/l glucose plus 5 mmol/l theophylline before measuring the insulin concentration in the culture medium. Cells that had initially been cultured for 2 days in 5 mmol/l glucose showed an increased insulin release, when subsequently cultured in 15 mmol/l glucose for 24 h. Theophylline potentiated the response and caused a decrease in cellular insulin content. Cells initially cultured in the presence of 15 mmol/l glucose showed unchanged insulin release during the subsequent 24-hour exposure to 15 mmol/l glucose, irrespective of the presence or absence of theophylline. The presence of NGF (100 ng/ml) during the initial 2-day culture period increased the insulin release in the presence of 15 mmol/l glucose and theophylline during the subsequent 24-hour culture period as compared to cells cultured in the absence of NGF. When cells were first exposed to either NA or NGF followed by exposure to 5 mmol/l glucose alone in the last 24-hour culture period, there was an increased insulin content. Rates of insulin biosynthesis remained unchanged irrespective of the glucose concentration in the culture medium. It is concluded that, already in early fetal development, B cells show glucose stimulation of insulin release albeit less pronounced than in the postnatal state.
Soluble CD30 Antigen in Human Colostrum
Authors: Bertotto A. , Vagliasindi C. , Gerli R. , Spinozzi F. , Castellucci G. , Fabietti G. , Crupi S. , Radicioni M. , Cozzali R. , Ferraro L. , Niccoli A. , De Rosa O. , Lupi C. , Brunelli R. , Merluzzi A. , Guadalupi D. , Parente C. , Pertici L. , Serra M. , Vaccaro R.
Published: October 2009

It is now well established that the CD30 glycoprotein is a surface antigen expressed by activated T cells producing T-helper (Th)-2-type lymphokines. Mounting laboratory evidence, however, suggests that CD30 expression is not confined to a functionally restricted subset of T cells, but also identifies activated cells with a Th-1 and Th-0 pattern of cytokine secretion. CD30-bearing T lymphocytes release a soluble form of the molecule (sCD30), which can be detected both in vitro and in vivo. In the present study, very high levels of sCD30 were found in colostrum from 20 puerperal women, but not in autologous and heterologous (nonpregnant women) blood samples. These data strongly support an involvement of CD30+ T cells in the immune processes which take place at the level of the mammary gland during pregnancy and lactation. Passively transferred immune components such as immunoglobulins, cytokines, macrophages, natural killer cells, granulocytes and memory/activated T cells, all of which may help the baby to fight off infections, have been revealed in human breast milk. However, how Th-2-type cytokine-secreting T cells or other T-cell types help to endow the congenitally immunocompromised newborn infant with extrinsic immunological support remains an open question.
Early Changes in Cutaneous Bilirubin and Serum Bilirubin Isomers during Intensive Phototherapy of Jaundiced Neonates with Blue and Green Light
Authors: Myara A. , Sender A. , Valette V. , Rostoker C. , Paumier D. , Capoulade C. , Loridon F. , Bouillie J. , Milliez J. , Brossard Y. , Trivin F.
Published: October 2009

We measured the changes in cutaneous bilirubin (Br) and serum Br photoisomers in two groups of 5 jaundiced newborn infants treated by intensive phototherapy (IP), one with blue light and the other with green light. Cutaneous Br was measured with a transcutaneous jaundice meter and photoisomers were measured by HPLC. Cutaneous Br decreased in the two groups as soon as IP began, and the skin was completely bleached within 3h with blue light only. Rebound occurred which was more marked after blue light IP. The main serum photoproduct was the 4Z-15E isomer, which reached a steady-state level within 1 h in both groups, whereas the lumirubin and 4E-15Z Br concentrations were slightly higher after green light IP. These data indicate that blue light is more suitable for IP, although this is not clearly explained by the production of more lumirubin.
Early Somatosensory Evoked Potentials in Preterm Infants: Their Prognostic Utility
Authors: Ekert Paul G. , Taylor Margot J. , Keenan Nancy K. , Boulton Jill E. , Whyte Hilary E.
Published: October 2009

We hypothesized that somatosensory evoked potentials (SEPs) recorded early in the course of a preterm infant life would be predictive of long-term neurodevelopmental outcome. We recorded unilateral, median nerve SEPs in 88 preterm infants twice in the first 3 weeks of life (SEP1 and SEP2). We found both SEP1 and SEP2 to be significantly associated with the presence of periventricular leukomalacia on head ultrasound (p = 0.04 and p = 0.02 for SEP1 and SEP2, respectively). Both SEP1 and SEP2 were predictive of later cerebral palsy (CP) (p = 0.03 and p = 0.003, respectively). False-positive results were frequent (13 of 17 for SEP1 and 20 of 28 for SEP2). A normal SEP, even when there was periventricular echogenicity on head ultrasound, was associated with a normal outcome in all but 1 instance. SEP1 and SEP2 were less accurate than head ultrasound findings of periventricular leukomalacia in the prediction of later CP (73, 69 and 93%, respectively). SEPs done in the first 3 weeks of life may provide additional prognostic information, particularly when the test is normal. Abnormal SEPs in this period must be interpreted cautiously.
The Contribution of Transporter-Dependent Uptake to Fetal Catecholamine Clearance
Authors: Bzoskie Lisanne , Blount Leslie , Kashiwai Kent , Humme James , Padbury James F.
Published: October 2009

These studies were designed to determine the contribution of cocaine-sensitive, transporter-dependent, reuptake mechanisms to the intrauterine norepinephrine clearance rate in chronically catheterized fetal sheep. Baseline norepinephrine clearance and appearance rates were 125 ± 20 ml/kg/min and 85 ± 11 ng/kg/min, respectively. Transporter-dependent clearance represented 40% of the intrauterine clearance rate. The effects of chronic cocaine administration on fetal catecholamine clearance and appearance rate were then determined in animals treated with daily infusion of saline or cocaine. The total intrauterine clearance rate and the transport-dependent component of intrauterine clearance decreased significantly following the week of drug or placebo treatment, p < 0.05. This was associated with a threefold increase in circulating catecholamine concentrations in both groups of animals, p < 0.05. These results demonstrate that intrauterine catecholamine clearance is highly dependent on transporter-dependent mechanisms. Chronic intrauterine stress, manifested by increased circulating norepinephrine, is associated with a significant decrease in norepinephrine clearance and may be important in the pathogenesis of the adverse effects of stress on the fetus and of drugs like cocaine, which block catecholamine reuptake.
Application of an Acoustic Cry Template to Evaluate At-Risk Newborns: Preliminary Findings
Authors: Robb Michael P. , Goberman Alexander M.
Published: October 2009

The durational characteristics of crying episodes produced among two groups of at-risk newborn infants are reported. The groups included preterm infants with diagnosed respiratory problems and preterm infants with diagnosed neurological problems. Each infant’s complete crying episode was audio-recorded and acoustically analyzed for overall occurrence of expiratory cry segments, inspiratory cry segments, and non-phonatory ‘pause’ segments. Remarkable similarity was found across risk groups with regard to the distributional occurrence of the cry features. Results obtained for the at-risk infants were highly similar to those observed for normal full-term newborns. These preliminary findings are taken to suggest that temporal features of newborn crying activity reflect a basic organizational response of the nervous system which is common to both normal and at-risk infants.
Hematological Parameters of the Mother and Neonatal Status during Normal Labor
Authors: Vitoratos N. , Louridas C. , Salamalekis E. , Loghis C. , Botsis D. , Zourlas P.A.
Published: October 2009

This study reviews the relationship between hematological parameters of the mother and the newborns status. Our material consisted of 180 pregnant women with singleton pregnancies who had an uncomplicated vaginal delivery. A negative relationship was noted between the pH and the maternal hemoglobin values both in the umbilical artery and vein (r = ––0.27, p < 0.001, for the umbilical vein and r = ––0.32, p < 0.0001, for the umbilical artery). A negative relationship was also noted between the umbilical vein pH and the maternal hematocrit, which was statistically significant (r = ––0.28, p = 0.001). A similar negative correlation was observed between the umbilical artery pH and the maternal hematocrit (r = ––0.32, p < 0.0001). In conclusion, maternal hematological parameters (hemoglobin, hematocrit) can affect the fetal acid base balance.
Fatty Acid Profiles of Rat Renal Phospholipids during Development
Authors: D’Antuono Cecilia L. , Sterin-Speziale Norma B.
Published: October 2009

The fatty acid content of rat renal phospholipids was examined during development. An increase in the arachidonic acid content of a particular fraction of phosphatidylcholine (PC2), phosphatidylethanolamine and phosphatidylinositol between 10 and 20 days of age could be observed in the papilla, and these levels were maintained into adulthood, while in the 20:4 content of phosphatidylserine changes were found between 30-day-old rats and adults. In the other fraction of phosphatidylcholine (PCI), saturated fatty acids such as 16:0 and 14:0 decreased, while no changes occurred in the stearic acid (18:0) content. The pattern found for the medulla did not differ significantly from that of the papilla. In contrast, the cortex content of arachidonic acid at 10 days of age was higher than that for papilla and medulla. Levels increased between 10 and 20 days of age, returning to the original values by 30 days with no further variations in the adult. These changes in arachidonic acid content with age in addition to the differences found between the three kidney zones might explain some causes of incomplete renal function in newborns.
Early-Life Polysensorial Stimulation and Nutrition: Topographic Levels of Susceptibility in the Rat Visual Cortex
Authors: Fernández Victor , Adaro Luis , Sanhueza-Tsutsumi Miguel , Inzunza Oscar , Bravo Hermes
Published: October 2009

The effects of environmental-nutritional interactions upon the development of the visual cortex were studied in Sprague-Dawley albino rats during lactation (5–22 postnatal days). Morphometric evaluations were assessed by measuring layer V pyramidal neurons, under camera lucida. The Golgi-Cox-Sholl technique permits quantitative studies of neurons by the precipitation of metallic mercury at random, without any selectivity. Length and frequency of dendritic segments showed significant differences due to rearing, nutrition, and topographic localization. Early environmental enrichment exerted its maximal benefits in undernourished pups, the influences being highly prominent in the lateroventral sector of the cortical plate that receives conspicuous inputs during development. These findings may provide bases for the design of clinical strategies to palliate the adverse effects of undernourishment and sensory deprivation on brain development, since their effects seem to follow pari passu the topographic sequences of cortical morphogenesis.
Oxalate Excretion during the First 7 Weeks in Very-Low-Birth-Weight Infants
Authors: Sonntag Josef , Schaub Jürgen
Published: October 2009

To determine reference values, we studied urinary excretion of oxalate prospectively and longitudinally in a cohort of 23 very-low-birth-weight (VLBW) infants. The urinary oxalate concentrations were evaluated in 24-hour urine samples by the oxalate oxidase method. Urine samples were obtained at 1, 2–3, 4–5 and 6–7 weeks of age. The median oxalate amount was 24 μmol/kg body weight/day with a 10th–90th percentile range of 16–45 in the 1st week. Oxalate excretion was highest in 2- to 3-week-old infants (median: 35; percentile range: 26–56 μmol/kg body weight/day). In the 4th–5th week, the median was 24 (percentile range: 15–47) μmol/kg body weight/day and in weeks 6–7 also 24 (percentile range: 10–36) μmol/kg body weight/day. Also, the urinary oxalate concentration as well as the oxalate-creatinine ratio showed increased values in the first 3 weeks of life and decreased values afterwards. In a multivariate analysis, nutrition or gestational age did not affect the urinary oxalate concentration, the daily amount excreted or the oxalate-creatinine ratio. The investigated parameters (oxalate amount and oxalate-creatinine ratio in urine) were significantly age dependent). The data show that urinary oxalate excretion in VLBW infants approaches levels that are in the same range as those of patients with urolithiasis. Thus the risk of nephrocalcinosis in VLBW infants may be increased.
Necrotizing Enterocolitis in Full-Term or Near-Term Infants: Risk Factors
Authors: Martinez-Tallo Emilia , Claure Nelson , Bancalari Eduardo
Published: October 2009

A retrospective case-control study of necrotizing enterocolitis (NEC) affecting infants weighing > 2,000 g at birth was performed to determine those factors which could contribute to the development of NEC. Twenty-four infants met the criteria of definite NEC. For each case the next 2 healthy newborns were matched as controls. When compared with the control group, NEC infants had a significantly higher frequency of prolonged rupture of membranes, chorioamnionitis, Apgar score < 7 at 1 and 5 min, respiratory problems, congenital heart disease, hypoglycemia, and exchange transfusions. Only 3 infants with NEC were healthy newborns with an unremarkable perinatal course before NEC. There were no differences in the frequency of preeclampsia, maternal diabetes, maternal drug abuse, meconium-stained amniotic fluid and polycythemia. These results indicate that most of these more mature infants have a predisposing factor before developing NEC.
Current Management of the Neonatal Abstinence Syndrome: A Critical Analysis of the Evidence
Authors: Theis Jochen G.W. , Selby Peter , Ikizler Yazemir , Koren Gideon
Published: October 2009

Objective: To systematically and critically analyse and summarise the published evidence for the rational choice of pharmacologic treatment of the neonatal abstinence syndrome (NAS), a frequently observed condition in neonates born to mothers who are dependent on physically addicting drugs. Design: Studies comparing different pharmacological agents for the treatment of NAS were identified utilising MEDLINE® and additionally the references cited in pertinent articles. The identified studies were critically analysed regarding their study designs and outcome measures. The reported data for the comparative efficacy of the drugs were summarised and evaluated. Results: Fourteen studies were identified, most of them comparing treatment of NAS with phenobarbital, paregoric or diazepam. However, none of these studies was conducted in a double-blind fashion. Frequently, treatment allocations were not properly randomised. Prenatal drug exposure varied and was often not sufficiently verified. Outcome measures and their evaluations differed widely. Due to the different study objectives and flaws in study design, a combined analysis of the published data in the form of a meta-analysis was not deemed possible. When attempting to compare efficacy, diazepam appears to be less efficacious in treating NAS than phenobarbital or paregoric. The relative efficacy of paregoric and phenobarbital appears to depend upon the antenatal exposure of the neonate and on the outcome measure of the study. Only two studies evaluate the efficacy of pure opioids, none of them in direct comparison to paregoric. It remains questionable whether paregoric, which contains the central stimulant camphor and a large amount of alcohol, should be the opioid of choice for the treatment of NAS. Conclusion: Most published studies were conducted prior to the development of clinical epidemiology and modern study design and thus yielded only very limited comparative data on the benefits of different treatment protocols. There is very little evidence regarding the efficacy of different pharmacological therapy regimens to treat NAS. More studies are required to produce the evidence needed to allow a rational choice between treatment modalities of NAS and thus to ensure optimal care of the neonates suffering from this condition.
Cephalocaudal Progression of Jaundice in Newborns Admitted to Neonatal Intensive Care Units
Authors: Knudsen A. , Ebbesen F.
Published: October 2009

The influence of several clinical factors on the cephalocaudal progression of neonatal jaundice was investigated in 377 newborns admitted to the neonatal intensive care unit for various reasons. Multiple regression analysis showed that, beyond the relationship to the plasma bilirubin concentration, the cephalocaudal color gradient was significantly, negatively related to gestational and postnatal age. Furthermore, the cephalocaudal progression of jaundice seemed more extended in females compared to males. The results are in agreement with a theory explaining that the cephalocaudal color gradient is due to conformational changes in the newly formed bilirubin albumin complexes.
Differences in Movement Quality at Term among Preterm and Term Infants
Authors: Kakebeeke Tanja H. , von Siebenthal Kurt , Largo Remo H.
Published: October 2009

Significant differences in movement quality at term are reported in high-risk preterm (n = 18), low-risk preterm (n = 21) and term (n = 20) infants. Movement quality was judged using 2-minute video collection of general movements; three parameters of movement quality could be assessed reliably in a semi-quantitative way: fluency, spatiotemporal variability and sequencing. The parameters fluency and variability correlated highly with each other (r = 0.47–0.99) while their correlations with sequencing were less (r = 0.42–0.67). Significant differences on all quality parameters were noted between term, low-risk preterm and high-risk preterm infants (p < 0.001–0.05). The findings indicate a significant impact of prematurity per se and brain damage on movement quality.
Testicular Arginine Vasopressin in the Developing Rat: A Possible Physiological Role
Authors: Tyson Deirdre L. , Landin Lois M. , David Raphael , Yoon Doug-Jin
Published: October 2009

Testicular immunoreactive arginine vasopressin (irAVP) has been shown to inhibit testosterone production by the Leydig cell in vitro. We studied pre- and postpubertal rats and the results are in agreement with the notion that such inhibition might occur in vivo and, therefore, could have physiological significance. Testicular irAVP and serum testosterone levels were measured in 14-, 21-, 28-, 35-, 42-, and 70-day-old rats. The testicular irAVP concentration was lowest in early prepubertal rats, increased significantly to the highest level at 35 days, then decreased at 42 days, and plateaued at 70 days of age. A pubertal increase in serum testosterone was observed at 42 days when AVP was decreasing. Thus, an inverse relationship was observed at the onset of pubertal maturation. These parameters were also measured in 3 groups of rats 1 week after hemicastration which was performed at the ages of 28, 35 and 70 days. In the 28-day-old rats there was a significant decrease in irAVP 1 week later, in contrast to the intact animal, whereas hemicastration performed at 35 and 70 days of age had no impact on irAVP. Our data suggest that the role of AVP may be physiologically relevant during the peripubertal period of testicular maturation in the rat.
Different Expression and Mobilisation of the Complement Regulatory Proteins CD35, CD55 and CD59 in Neonatal and Adult Neutrophils
Authors: Lothian C. , Dahlgren C. , Lagercrantz H. , Lundahl J.
Published: October 2009

We investigated the expression and the N-formyl-methionyl-phenylalanine (fMLP)- and interleukin-8 (IL-8)-induced mobilisation of the complement regulatory proteins CR1 (CD 35), decay-accelerating factor (CD55) and CD59 on neutrophils in neonates and adults. The expression of CD35 on resting neonatal neutrophils was significantly higher than in adults. Both fMLP and IL-8 increased CD35 expression more markedly in adults. CD55 on resting neutrophils in neonates was significantly higher than in adults, but did not further increase upon fMLP stimulation as opposed to adults. The increase in CD59 expression was more pronounced in adult neutrophils and was significantly higher than in neonates after fMLP activation. The addition of the protease inhibitor phenylmethanesulphonyl fluoride during fMLP activation improved the upregulation of CD 3 5 significantly more in neonates, but not CD 55 or CD59. This effect could be replaced by human normal sera. These data demonstrate that differences exist between neonatal and adult neutrophils with respect to the expression and mobilisation of functional receptors related to protection from autologous complement lysis and may indicate differences in the efficiency to circumvent complement-mediated cell damage at the inflammatory site.
Metabolism of 4,7,10,13,16,19-Docosahexaenoic Acid in Isolated Perfused Adult and Newborn Pig Eyes
Authors: Abran Daniel , Chemtob Sylvain , Levy Emile , Gavino Grace , Gavino Victor C.
Published: October 2009

We performed open-circuit perfusions of newborn and adult pig eyes to study the age-dependent metabolism of 4,7,10,13,16,19-docosahexaenoic acid (DHA) in this organ. DHA taken up by the perfused eyes was partitioned into glycerolipids, β-oxidation, and the intracellular nonesterifïed fatty acid pool. In newborn eyes, DHA was incorporated into structural lipids to a greater extent than in adult eyes. Competition experiments suggest that the adult eye is more selective for DHA than the newborn eye. Finally, pulse-chase data indicate that DHA transport from the circulation across the retinal pigment epithelium and into the retina is more rapid in adult than in newborn eyes. The results are discussed with respect to the rapid accumulation of retinal DHA in early life and the avid retention of this fatty acid by the adult retina.
Influence of Different Levels of Neonatal Mild/Moderate Hypoxia-Ischemia in Learning Abilities of Rats at the Age of One Month
Authors: Carratalá F. , Moya M. , Ferrer E.
Published: October 2009

We studied the effects of mild/moderate hypoxia-ischemia in 90 newborn Wistar rats divided into 3 groups. Two of the three groups were submitted to two different levels of hypoxia (FiO2 = 0.05, group F5 and FiO2 = 0.1, group F10) and the third to normoxia (FiO2 = 0.21, group F21) in a thermoneutral and controlled environment. We examined their influence in a maze test 1 month later after two training trials, a 48-hour fasting period and handling stress just before starting the trial. The learning ability in animals exposed to FiO2 = 0.1 was lower (significantly higher number of squares crossed F10 = 37.57 ± 20.8) than the others (F21 = 26.22 ± 19.25; F5 = 26.56 ± 14.97; p = 0.0481), while group F5 had the best learning improvement measured by the reduction in wrongly crossed squares (F5 day 25 = 25.08 ± 19.9; day 26 = 13.04 ± 13.91; day 30 = 10.08 ± 9.66; p = 0.0427). These differences in group F5 as well as the maze solution profile (defined by analysis of 15 variables considered) was significantly closer to the control group F21 than the less hypoxied group F10. We discuss whether these paradoxical results in learning abilities reflect the influence of the hypoxic levels to which the newborn animals were submitted, or to the effects of uncontrolled variables in this study.
Enhanced Diltiazem Deacetylase Activity in Pre-Term and Full-Term Rabbits Compared with Adult Rabbits
Authors: Fraile L.J. , Aramayona J.J. , Bregante M.A. , García M.A. , Solans C.
Published: October 2009

The in vitro metabolic activity of the esterase responsible for the hydrolysis of diltiazem (DTZ) to its deacetylated metabolite (Ml) was determined in an age-dependent fashion using the rabbit as an animal model. The presence of the enzyme in several tissues (liver, lung, small ntestine, and brain) and in whole blood from pre-term and full-term fetuses, full-term newborns, yound and adult rabbits was examined. To this end, DTZ was spiked to 10000-g tissue homogenates and whole blood to yield a final concentration of 1 μg/ml. Serial samples were withdrawn from the incubation medium up to 240 min and assayed for DTZ and M1 concentration. In all tissues examined there was a net production of M1. Chemical breakdown and stability studies confirmed the metabolic origin of the Ml formed throughout the incubation. In pre-term fetuses (25 days of gestation) the brain was found to be the most active tissue in eliminating DTZ (brain > liver > lung > small intestine). This trend changed in young and adult rabbits (lung = brain > liver > small intestine). Although an important age-dependent DTZ deacetylase activity was observed in blood, it was not included in the comparison between organs because of the unequal composition of the incubation medium. In conclusion, results showed that fetuses and newborn rabbits have a similar, and in some instances higher, DTZ deacetylase activity to that in adults (p < 0.05). In vitro findings were further confirmed by in vivo experiments.
Human Meconium Has Potent Antioxidative Properties
Authors: Kääpä Pekka , Kytölä Jaakko , Soukka Hanna , Ahotupa Markku
Published: October 2009

In vitro the antioxidative capacity of pooled and lyophilized human meconium, measured by chemiluminescence, was compared to that of three potent antioxidants: vitamin C, a vitamin E analogue and a synthetic antioxidant, butylated hydroxytoluene. Meconium showed a significant superoxide trapping and peroxidation prevention capacity, but its capacity to trap peroxyl radicals was minor. These effects of meconium were possibly due to bilirubin and ubiquinol-10, both found in high concentrations in meconium. It is speculated that human meconium may have a physiological role as an important endogenous antioxidant during perinatal transition.
Antithrombin-lll Substitution in Preterm Infants – Effect on Intracranial Hemorrhage and Coagulation Parameters
Authors: Brangenberg R. , Bodensohn M. , Bürger U.
Published: October 2009

In preterm infants the activity of antithrombin III (AT-III), the main inhibitor of thrombin, is reduced depending on gestational age and complications such as sepsis or respiratory distress syndrome. Babies with low levels of AT-III have been shown to have a higher mortality and an increased incidence of intracranial hemorrhage. In our study we tried to show the effect of early AT-III substitution on coagulation parameters and the incidence of intraventricular hemorrhage (IVH). One hundred three preterm infants at a gestational age of 25–32 weeks (mean 28.9 weeks; birth weight 600–2,170 g, mean 1,285 g) received AT-III concentrate at a single dosage of 50–200 IU/kg on the day of birth and subsequently only in case of a new decrease below an AT-III activity of 50%. We measured AT-III activity, Quick’s prothrombin time (PT), partial thromboplastin time (PTT) and platelet count on the day of birth, and after 1 and 5–9 days in 25 patients. AT-III activity before substitution was lower than described for term infants (20–72%, mean 40%). Within the first week of life Quick’s PT and PTT reached almost term values. No significant differences of the platelet count were found within the first week of life. The incidence of IVH was lower than in current epidemiologic studies: in only 13% of the study patients. Six percent of the infants had IVH grade I, 3% grade II, 4% grade III and none grade IV. Therefore, in preterm infants AT-III substitution may reduce the incidence and progression of intracranial hemorrhage.
Maternal, Placental and Cord Zinc Components in Healthy Women with Different Levels of Serum Zinc
Authors: Vargas Zapata Carmiña L. , Melo Márcio R.R. , Donangelo Carmen M.
Published: October 2009

Serum zinc is known to decrease during pregnancy, but the range of individual values at the end of normal gestation may be considerably large, with uncertain physiological significance in terms of maternal zinc status and maternal-fetal transfer of zinc. In this study we compared several maternal and cord blood indices of zinc status, placental zinc, placental metallothionein and the relationship between maternal, cord and placental components, in 40 healthy pregnant women at delivery with different levels of serum zinc. Subjects were divided into three groups according to serum zinc using as cutoff points the lower and upper quartile values [LZn, < 7.6 µmol/l (n = 10); MZn, 7.6–10.7 µmol/l (n = 20), and HZn, > 10.7 µmol/l (n = 10)]. Habitual zinc intakes were similar in all groups (average 11.5 mg/day). Considering all women, maternal serum and erythrocyte zinc correlated significantly (r = 0.40; p = 0.021). Maternal erythrocyte zinc was higher (p < 0.01) in HZn compared to the other groups. Maternal and cord values of serum zinc correlated significantly (r = 0.43; p = 0.006). Cord serum zinc values were very similar in LZn and MZn but were higher (p < 0.01) in HZn. Cord erythrocyte zinc levels were similar in all groups and about 20–25% of the maternal values. Cord erythrocyte metallothionein levels were also similar in all groups and similar to maternal values. Comparing the percentage distribution of zinc in maternal and cord serum fractions, major differences were observed in HZn, with zinc in albumin fraction being 70% in cord compared to 56% in maternal serum. There was a higher (p < 0.01) percentage of zinc bound to α2-macroglobulin fraction in maternal serum of HZn compared to maternal serum of the other groups. Maternal and cord zinc in the albumin fractions correlated significantly (r = 0.48; p = 0.002) particularly in HZn (r = 0.71; p < 0.021). Placental zinc correlated negatively (r = ––0.34; p = 0.035) with zinc in the maternal α2-macroglobulin fraction, but did not relate to placental metallothionein, which had similar levels in all groups (average 0.28 nmol/g wet tissue). Placental zinc levels were lower (p < 0.01) in HZn. Our results indicate that high levels of maternal serum zinc in healthy women at delivery may be related to maternal tissue zinc redistribution that could favor diffusional components of maternal-fetal transfer of zinc.
Heart Rate Biorhythm Changes during the First Three Months of Life
Authors: Ardura J. , Andrés J. , Aldana J. , Revilla M.A. , Aragón M.P.
Published: October 2009

Heart rate (HR) was recorded in healthy full-term newborns aged 1–90 days. The aim of this study was to study the existence of circadian and/or ultradian rhythms in HR to determine maturity. HR was recorded during 24 h, at 30-min intervals, at different postnatal ages. Six groups were investigated: day 1 (group 1); day 7 (group 7); day 15 (group 15); day 30 (group 30); day 60 (group 60), and day 90 (group 90). The chronograms for HR showed peaks and nadirs along the 24-hour periods, and the cosinor analysis proved the existence of 3-hour ultradian rhythm in groups 1, 7 and 30, and a 12-hour ultradian rhythm in group 90 (p < 0.01 in all cases). The same type of analysis confirmed the existence of a circadian rhythm in group 30. Similar results were obtained for groups 60 and 90 (p < 0.05). In conclusion: at birth, newborns have an endogenous ultradian period of 3 h. A circadian rhythm appears within 15–30 days of postnatal life.
Possible Role of Uric Acid as an Antioxidant in Premature Infants
Authors: Schrod L. , Neuhaus T. , Speer C.P. , Girschick H.
Published: October 2009

Uric acid (UA) is a water-soluble antioxidant in human body fluids. In umbilical cord blood of 172 neonates with gestational ages between 22 and 42 weeks, UA concentrations were between 50 and 990 μmol/l. There was no correlation with gestational age. Infants with an umbilical cord pH < 7.0 had markedly lower UA concentrations in cord blood than neonates without severe acidosis. UA levels increased during the first 24 h of life and subsequently declined within 2 weeks to lower levels than in older children. In tracheal aspirates (TA), UA at concentrations of about 10––4 mol/l was found capable of effectively scavenging free oxygen radicals. Luminol-dependent chemiluminescence activity of isolated TA phagocytes or alveolar macrophages was suppressed by UA dose dependently, with a 100% reduction at UA concentrations of 10––3 mol/l. On the assumption that oxidative stress contributes to the development of chronic lung disease (CLD), in premature infants the ratio of the antioxidant UA and malondialdehyde (MDA) as a marker of oxidative injury was measured in serially obtained TA of 102 ventilated premature infants with birth weights < 1,500 g. At the age of 3–14 days, infants who later developed severe CLD had significantly lower TA UA/MDA ratios than infants without CLD development. In infants with moderate CLD, UA/MDA ratios were comparable to those in the non-CLD group until day 5. During the next 2 weeks, decreasing ratios of UA/MDA paralleled lung injury with increased oxygen requirement and microvascular permeability. Serum UA concentrations did not differ between groups. It is speculated that UA may be physiologically important as an antioxidant in the epithelial lining fluid of the respiratory tract in neonates during the 1st week of life.