bluuebunny/crossref_metadata_2025_split huggingface dataset:
Unconjugated and Conjugated Bilirubin Pigments during Perinatal Development
Authors: Kaplan Michael , Muraca Maurizio , Hammerman Cathy , Vilei Maria Teresa , Rubaltelli Firmino F. 
Published: April 2003

<b>Objective: </b>To determine the effect of phototherapy on serum conjugated bilirubin fractions, an index of bilirubin conjugation, in hyperbilirubinemic neonates. <b>Method: </b>Serum was sampled from 21 jaundiced (serum diazo total bilirubin ≥274 µmol/l), term, otherwise healthy neonates prior to starting phototherapy, and 24 h after the commencement of treatment. Alkaline methanolysis followed by reverse-phase, high-performance liquid chromatography, specific for determination of unconjugated bilirubin and the monoconjugated and diconjugated fractions of total conjugated bilirubin in serum, was used for the analysis. Prephototherapy values were compared to those at 24 h. <b>Results: </b>Serum total bilirubin and total conjugated bilirubin values decreased during the study period, from 220 (211–239) to 177 (157–213) µmol/l (median (25–75% range)) p = 0.001, for the former, and from 1.4 (0.87–1.57) to 0.93 (0.69–1.84) µmol/l, p = 0.005, for the latter. These parameters decreased by a similar percentage (–16.6 ± 14.8% and –14.0 ± 23.4%, respectively; p > 0.05). Both monoconjugated and diconjugated bilirubin, calculated as a percentage of total conjugated bilirubin, remained constant over the study period (88.2 (72.2–96.4)% before phototherapy and 92.5 (87.3–96.8)% after 24 h, p > 0.05, for monoconjugated bilirubin, and 11.8 (3.6–27.8)% and 7.5 (3.2–12.7)%, respectively, p > 0.05, for diconjugated bilirubin). <b>Conclusions: </b>Serum total conjugated bilirubin values decreased in parallel to serum total bilirubin levels during phototherapy, maintaining a constant relationship between these two parameters. The ratios of monoconjugated and diconjugated bilirubin to total conjugated bilirubin remained constant. These findings imply that phototherapy does not alter bilirubin conjugation in hyperbilirubinemic neonates.
Effect of Inhaled Nitric Oxide in Endothelin-1-Induced Pulmonary Hypertension
Authors: Truog William E. , Norberg Michael , Thibeault Donald W. 
Published: April 2003

The interaction of two vasoactive substances, the vasodilator nitric oxide (NO) and the complex-acting peptide endothelin-1 (ET-1), may help explain the pathophysiology of pulmonary hypertension, an important part of many pulmonary disorders in neonates. To understand better the interactions of inhaled NO and ET-1, we investigated the effects of ET-1 infusions with and without inhaled NO in two groups of piglets, one group pretreated with <i>L</i>-nitro-arginine methylester (<i>L</i>-NAME) and the other not pretreated. Inhaled NO (60 ppm) was administered during infusion of 1.0 µg/kg or 2.5 µg/kg of ET-1. In animals not pretreated with <i>L</i>-NAME, the increase in PVR and in SVR induced by either dose of ET-1 was not reduced with administration of NO. The increase in systemic vascular resistance with ET-1 was greater (mean increase of 50% above baseline with 1.0 µg/kg ET-1 and 100% with 2.5 µg/kg ET-1 by 5 min) than the increase in PVR, but the PVR/SVR ratio did not change during ET-1 administration. In contrast, animals pretreated with <i>L</i>-NAME did demonstrate inhibition of ET-1-induced increase in PVR with NO. No differences in effects on SVR were noted. We conclude that ET-1-induced increases in PVR are not diminished by 60 ppm of inhaled NO unless there has been inhibition of endogenous NO production.
Delivery of Total Parenteral Nutrition (TPN) via Umbilical Catheterization: Development of a Piglet Model to Investigate Therapies to Improve Gastrointestinal Structure and Enzyme Activity during TPN
Authors: Park Yoo Kyoung , Monaco Marcia M. , Donovan Sharon M. 
Published: April 2003

Nutritional support of preterm infants by total parenteral nutrition (TPN) is common; however, TPN compromises intestinal structure and enzyme activity. Our goal was to develop a piglet model to assess the effect of limited enteral stimulation with formula and insulin-like growth factor-I (IGF-I) on intestinal morphology and enzyme activity. A nutritionally complete TPN solution was infused for 7 days and piglets were gavaged twice daily with 4 ml sterile water, formula, or formula containing 1,000 µg/l IGF-I. Litter mate piglets fed formula served as orally fed controls. On day 7, body weights and plasma hormone profiles of TPN and orally fed piglets were similar. However, intestinal weight, jejunal and ileal villus height and surface area, and mucosal lactase and sucrase activity of TPN piglets was reduced by ∼50%. No effect of limited enteral stimulation or IGF-I was observed likely due to the small volume of formula administered enterally, which resulted in a low dose of IGF-I (4.3 µg IGF-I/kg/day).
Are Biochemical Parameters of Lung Maturation from Gastric, Tracheal, and Pharyngeal Aspirates Comparable?
Authors: Rüdiger Mario , Haupt Renate , Rüstow Bernd , Wauer Roland R. 
Published: April 2003

Phospholipid parameters – lecithin/sphingomyelin (L/S) ratio and palmitic acid/stearic acid (P/S) ratio – of gastric (GA), pharyngeal (PA), and tracheal aspirates (TA) have often been used for estimation of lung maturation. However, it was not known whether values from different sources can be alternatively used. The study was performed to test whether P/S and L/S ratios in GA, PA, and TA are comparable. 11 GA, 30 PA, and 10 TA were obtained from infants within 10 min after birth. All infants were healthy, vaginally delivered with no respiratory distress, and had a gestational age ≥34 weeks. Patterns of fatty acids were determined by gas chromatography and the L/S ratio by high-performance liquid chromatography. We found lower L/S ratios in GA (16.5 ± 5.2) when compared with PA (39 ± 16) or TA (41 ± 15; p < 0.01); there were no differences between PA and TA. The P/S ratio was in the same range in PA and TA, but lower in GA. As compared with TA and PA, in GA the relative percentage of palmitic acid of all fatty acids was lower, the percentage of monounsaturated fatty acids, however, higher. We conclude that phospholipid parameters of lung maturation in PA and TA, but not in GA, can be alternatively used.
Maternal and Neonatal Lead Exposure in Southern Italy
Authors: Carbone Ruggiero , Laforgia Nicola , Crollo Elisabetta , Mautone Angela , Iolascon Achille 
Published: April 2003

We evaluated the blood lead levels in 159 pregnant women and in their healthy newborns at birth. The blood lead levels were higher in mothers as compared with neonates, with a linear correlation between maternal and neonatal levels. The blood lead levels were also higher in neonates as compared with infants aged 6–12 months, and, besides, 2.5% of the newborns had blood lead levels >10 µg/dl, the actual level of concern according to the Center for Disease Control. The study of blood and urinary lead levels during the 1st week of life showed a steady decrease of blood lead levels, together with increasing levels of urinary lead. The mechanism of renal elimination is important to avoid persistently high free blood lead levels, with possible deposition in tissues with high lead affinity, such as bone. In newborns, the possibility of a functional renal insufficiency during the first days of life suggests that newborns with high cord blood lead levels and impaired renal function could be at high risk of lead toxicity, so that it could be advisable to perform a careful and prolonged follow-up.
Increase in the Renal Damage Induced by Paracetamol in Rats Exposed to Ethanol Translactationally
Authors: Llamas Javier , Martínez Ma Consolación , Jaramillo-Juárez F. , Muñoz-Fernández Luis , Bustos Luis , Reyes José L. 
Published: April 2003

Administration of ethanol (8%) or acetone (1%) to nursing dams in the drinking water, for 10 days, increased the nephrotoxicity of paracetamol (APAP) in the 14-day-old lactating offspring. The percentage of proximal tubular cells with evidence of necrotic damage in male rats was higher in those animals that received APAP (500 mg/kg, i.p.) and whose nursing rats were exposed to ethanol (25.0 ± 8.4%) or acetone (17.2 ± 1.2%), than in the group treated with APAP alone (10.6 ± 1.6%). The activity of urinary N-acetylglucuronidase was also significantly higher in the rats exposed translactationally to ethanol or acetone than in animals treated with the APAP alone. Nephrotoxicity showed a sexual dimorphic pattern with a higher toxicity in male than in female rats. The percentage of necrotic tubules in the male rats not exposed to inductor was 10.6 ± 1.6%, and in female rats 5.0 ± 1.4% (p < 0.05). Animals exposed to ethanol or acetone and treated with APAP showed less weight gain than the group treated only with APAP. Our results suggest that renal toxicity is enhanced in the nursing animals that were exposed, via maternal milk, to ethanol or acetone (inductors of cytochrome P<sub>450</sub>2E1), than in the control animals. This circumstance may be relevant in alcoholic women while they are lactating.
Platelet-Activating Factor Is an Important Mediator in Hypoxic Ischemic Brain Injury in the Newborn Rat
Authors: Akisü Mete , Kültürsay Nilgün , Coker Isil , Hüseyinov Afig 
Published: April 2003

Hypoxic-ischemic encephalopathy is still a very important cause of neonatal mortality and morbidity. Recently, platelet-activating factor (PAF) has been accused of being responsible for the neuronal damage in hypoxic-ischemic brain. We investigated tissue PAF concentrations in hypoxic-ischemic brain injury in immature rats. Endogenous PAF concentration in brain tissue showed a marked increase in hypoxic-ischemic pups (85.6 ± 15.5 pg/mg protein) when compared to that of control (9.05 ± 3.1 pg/mg protein). In addition, we examined the effects of flunarizine, a selective calcium channel blocker, and Ginkgo biloba extract (EGb 761) on endogenous PAF concentration in hypoxic-ischemic brain injury. Endogenous PAF concentrations in both flunarizine-pretreated (16.6 ± 4.8 pg/mg protein) and EGb 761-pretreated (33.5 ± 8.9 pg/mg protein) pups were significantly lower than the untreated group. These results indicate that PAF is an important mediator in immature rat model of cerebral hypoxic-ischemic injury. The suppressor effect of flunarizine and EGb 761 on PAF production may open new insight into the treatment of hypoxic-ischemic brain injury.
Reduced Capacity of Neonatal Lymphocytes to Inhibit the Growth of <i>Candida albicans</i>
Authors: Shareef Maliha J. , Myers Thomas F. , Mathews Herbert L. , Witek-Janusek Linda 
Published: April 2003

Opportunistic microorganisms produce significant morbidity and mortality in preterm and term infants. Because of the heightened susceptibility of infants to opportunistic fungal infections, neonatal lymphocytes were assessed for their capacity to inhibit the growth of Candida albicans. Lymphocytes from both preterm and term cord blood demonstrated significantly less effect upon C. albicans than did lymphocytes from adults. Neonatal lymphocytes of infants <32 weeks of gestation showed a marked reduction in growth inhibitory capacity compared to infants >32 weeks of gestation. Lymphocytes from female infants had a significantly greater fungal growth inhibitory capacity than did lymphocytes from male infants. These results show that neonatal lymphocytes have a reduced capacity to inhibit the growth of <i>C. albicans.</i> This reduced antifungal capacity may underlie the increased susceptibility of such infants to opportunistic microorganisms, like <i>C. albicans.</i>
Complications of Airway Management in Very-Low-Birth-Weight Infants
Authors: da Silva Orlando , Stevens D. 
Published: April 2003

<i>Objective:</i> To define the incidence of complications of endotracheal intubation and the factors associated with these complications. <i>Study Design:</i> During a 22-month period, 227 intubated infants weighing <1,501 g were followed prospectively in a neonatal intensive care unit. Detailed records of events associated with airway management were kept after every intubation, in addition to clinical data. <i>Results:</i> Eleven infants (4.8%) developed respiratory stridor after extubation which was treated with either systemic corticosteroids, racemic epinephrine and/or reintubation for respiratory failure. Four infants were submitted for bronchoscopy, mild subglottic stenosis with tracheal edema was found in 1 patient, granulation tissue and airway edema were noted in 3 infants. Traumatic intubation, prolonged ventilation, multiple intubations and bacterial colonization of the endotracheal tube were the factors associated with postextubation stridor. <i>Conclusions:</i> Subglottic stenosis is an infrequent complication of endotracheal intubation with current airway management of very-low-birth-weight infants. Less severe complications are still common, but they are usually amenable to clinical treatment. Bronchoscopy should be performed selectively only in infants with clinical evidence of airway obstruction after extubation.
Effect of Age and Weaning on Gastric Mucosal Injury in Developing Rats
Authors: Kaneko Hiroaki , Tabata Masahiko , Tomomasa Takeshi , Morikawa Akihiro 
Published: April 2003

We evaluated ethanol- and HCl-induced mucosal damages in developing rats. The degree of damage induced by ethanol and HCl was greatest in 1-week-old rats and decreased significantly with age until 4 weeks; thereafter it increased again. To evaluate the effect of weaning on the maturational changes in mucosal defense, we compared ethanol-induced mucosal damage among three groups of newborn rats: (1) receiving milk only; (2) receiving only rat chow from 14 days of age, and (3) having free access to milk and chow. There were no significant differences at 18 and 21 days of age. The mucus thickness increased with age until 8 weeks and was not affected by weaning. In conclusion, developmental changes occur in gastric mucosal protection in rats. Weaning does not have a significant effect on these changes.
High-Frequency Oscillatory Ventilation, Partial Liquid Ventilation, or Conventional Mechanical Ventilation in NewbornPiglets with Saline Lavage-Induced Acute Lung Injury
Authors: Degraeuwe Pieter L.J. , Thunnissen Frederik B.J.M. , Vos Gijs D. , Blanco Carlos E. 
Published: April 2003

It has been reported that, in diseased lungs, either partial liquid ventilation (PLV) or high-frequency oscillatory ventilation (HFOV) can improve oxygenation better and with less lung injury than conventional mechanical ventilation (CMV). This study was intended as a preclinical comparison between the effects of HFOV, PLV and CMV on gas exchange, lung mechanics and histology. Fifteen anesthetized newborn piglets, with respiratory insufficiency due to repeated saline lung lavage, were allocated to either a PLV, HFOV or CMV (n = 5 each) strategy, and treated for 4 h. Within 30 min of commencing therapy, PLV, HFOV, and CMV improved arterial Po<sub>2</sub> (Pa,o<sub>2</sub>), alveoloarterial oxygen gradient (P(A-a),o<sub>2</sub>), oxygenation index (OI), venous admixture (va), and arterial Pco<sub>2</sub> (Pa,co<sub>2</sub>). After 4 h, oxygenation parameters (Pa,o<sub>2</sub>, P(A-a),o<sub>2</sub>, OI and venous admixture) were significantly better in the HFOV group than in the PLV group; the CMV group showed a higher Pa,o<sub>2</sub> and lower OI than the PLV group. Gas exchange at the end of the experiment was not different from baseline in the HFOV and CMV groups. Lung histology and morphometry were performed after perfusion-fixation at endotracheal deflation pressure corresponding to mean airway pressure at the end of the experiment. Lung injury score and mean linear intercept were not different between the three treatment groups. We conclude that in this model, gas exchange improved significantly in all three ventilation strategies. Indices of oxygenation improved less during PLV. The saline lavage-induced acute lung injury model used as in this study, is less stable than previously thought. The final lung injury is not influenced by the ventilation strategy. We speculate that the impaired gas exchange during PLV is an expression of diffusion limitation and ventilation-perfusion mismatch in a recovering lung.
Efficacy of Anti-Tumor Necrosis Factor-Alpha Antibody as an Adjunctive Therapy in Experimental <i>Escherichia coli</i> Meningitis in the Newborn Piglet
Authors: Park Won Soon , Chang Yun Sil , Ko Sun Young , Kang Mi Jung , Han Jung Mie , Lee Munhyang 
Published: April 2003

This study was done to evaluate the efficacy of anti-tumor necrosis factor alpha (anti-TNF-α) antibody as an adjunctive therapy in neonatal bacterial meningitis. Newborn piglets were divided into three groups: 8 in the control group, 13 in the meningitis group (MG), and 10 in the meningitis with anti-TNF-α antibody group (AG). Meningitis was induced by intracisternal injection of 10<sup>8</sup> colony-forming units of <i>Escherichia coli</i> in 100 μl of saline. In the AG, 200 μl of anti-TNF-α antibody was also given intracisternally. In the AG, the elevated cerebrospinal fluid TNF-α level observed in the MG was completely abolished, and increased intracranial pressure, hypoglycorrhachia, and CSF pleocytosis observed in the MG were downmodulated. But blood, brain, and CSF lactate levels remained elevated in both MG and AG. Increased brain cell membrane lipid peroxidation products and decreased Na<sup>+</sup>,K<sup>+</sup>-ATPase activity observed in the MG were not attenuated in the AG. These results indicate that anti-TNF-α antibody was not particularly effective as an adjunctive therapy in attenuating acute inflammatory responses and ameliorating brain damage in neonatal bacterial meningitis.
Goat Fetuses Disconnected from the Placenta, but Reconnected to an Artificial Placenta, Display Intermittent Breathing Movements
Authors: Kozuma Shiro , Nishina Hidenori , Unno Nobuya , Kagawa Hideyuki , Kikuchi Akihiko , Fujii Tomoyuki , Baba Kazunori , Okai Takashi , Kuwabara Yoshinori , Taketani Yuji 
Published: April 2003

To investigate whether placental factors are involved in the intermittent breathing movements in goat fetuses, we assessed electrocortical activity (ECoA) and tracheal pressure in 5 fetuses (124–135 days) separated from the placenta and connected for 48 h to an extrauterine fetal incubation system that provided umbilical arteriovenous extracorporeal membrane oxygenation. The fetal physiological condition on this system was almost the same as that in utero for at least 48 h after the preparation. All fetuses showed intermittent low-voltage ECoA and breathing movements. The breathing movements occurred almost exclusively during periods of low- voltage ECoA. The proportions of time spent in low-voltage ECoA and breathing movements were 48–57% and 46–56%, respectively. In conclusion, breathing movements of fetuses on the extrauterine incubation system were episodic, suggesting that intermittent breathing movements are intrinsic to fetuses, independent of placenta-derived factors.
Functional Role of Sialic Acid in IgG Binding to Microvillus Membranes in Neonatal Rat Intestine
Authors: Gill Ravinder Kaur , Mahmood Safrun , Nagpaul Joginder Pal , Mahmood Akhtar 
Published: April 2003

A close parallelism exists between sialylation and endocytotic activity of the small intestine during postnatal development in rats. Thus, the binding of <sup>125</sup>I-labelled IgG to microvillus membranes and its relationship to membrane sialic acid has been studied in suckling rat intestine, during (a) postnatal development; (b) cortisone-induced precocious maturation, and (c) after desialylation of brush borders by neuraminidase treatment. Neuraminidase-treated membranes exhibited low (42%, p < 0.001) IgG binding. The observed decrease in IgG binding to desialylated membranes was associated with a decrease in the value of affinity constant, (–Ka = 0.4 × 10<sup>6</sup> <i>M</i><sup>–1</sup> in control and 0.23 × 10<sup>6</sup> <i>M</i><sup>–1</sup> in desialylated membranes). The number of IgG-binding sites (2.3 nmol/mg protein) was unchanged under these conditions. A similar decrease (50%) in IgG binding to brush borders was also observed in cortisone-injected pups. This was associated with reduced sialic acid (37%) content of the membranes compared to the controls. The value of –Ka was reduced from 0.4 × 10<sup>6</sup> <i>M</i><sup>–1</sup> in the control to 0.3 × 10<sup>6</sup> <i>M</i><sup>–1</sup> in the hormone-injected pups. The number of binding sites (n) was decreased from 2.2 to 1.4 nmol/mg protein under these conditions. Low concentrations of calcium (0.1–1.6 m<i>M</i>) in the incubation medium enhanced IgG binding (p < 0.001) to brush borders in pups but there was no change in binding of IgG to the membranes at 2 m<i>M</i> Ca<sup>2+</sup> concentration compared to controls. Addition of Zn<sup>2+</sup> or Mg<sup>2+</sup> did not affect IgG binding under these conditions. These findings suggest a functional role of Ca<sup>2+</sup> and sialic acid residues of the membrane glycans in IgG-receptor interactions in suckling rat intestine.
Effect of Increased Brain GABA Concentrations on Breathing in Unanesthetized Newborn Rabbits
Authors: Monin P. , Aranda J. , Bansal R. , Trippenbach T. 
Published: April 2003

Evidence suggests that γ-aminobutyric acid (GABA) is involved in control of breathing and in the hypoxia-related ventilatory depression in newborns. However, this evidence is obtained mainly from studies on anesthetized animals. Because anesthesia may interfere with the GABA system, the objectives of our study were to examine effects of GABA on ventilation (V<sub>E</sub>) and ventilatory response to hypoxia and to reveal effects of repeated hypoxia on GABA concentrations in unanesthetized newborns. The study was performed in rabbits in two age groups: 1–3 days old (group I) and 10–14 days old (group II). To increase brain endogenous GABA concentrations, rabbits were injected with an inhibitor of GABA transaminase, aminooxyacetic acid (AOAA; 20 mg/kg i.p.). To prevent postmortem formation of GABA, at the end of experiments the rabbits received an inhibitor of glutamic acid decarboxylase, IP-3-mercaptopropionic acid (100 mg/kg i.p.). Animals were studied in normoxia alone, or they were exposed for 15 min to 8% O<sub>2</sub> before and 10 and 35 min after saline or AOAA. GABA concentrations were measured in brainstem, cerebrum, and cerebellum by means of a capillary electrophoresis. In group I, AOAA had no respiratory effects. In group II, AOAA decreased V<sub>E</sub>, tidal volume, and mean inspiratory flow in normoxia and reversed V<sub>E</sub> decline during hypoxia 10 min after the injection, GABA concentrations were not age dependent and the highest in the brainstem. Repeated hypoxia increased the cerebellar GABA concentrations and had no effect in group I. These results imply that in unanesthetized rabbits, GABAergic neurotransmission in the respiratory control network becomes functional by the 2nd week of life, but it does not contribute to the biphasic ventilatory response to moderate hypoxia. In contrast, GABA-evoked block of the cerebellar inhibitory input during hypoxia may be responsible for the reversal of the V<sub>E</sub> decline in unanesthetized newborns.