Yoshiyuki Uetani

Comparison of bilirubin production in Japanese and Caucasian infants.

Bilirubin production, as indexed by serum carboxyhemoglobin (HbCOc), was studied in a group of normal term Japanese infants and Caucasian controls during the second to third day of life. Stringent entry criteria were employed in order to eliminate infants with hemolysis or other known causes of increased bilirubin production. The mean HbCOc of the Japanese infants (0.69 +/- 0.15% sat) was significantly higher than that of the Caucasian infant (0.58 +/- 0.17% sat). The serum total bilirubin was also significantly higher in Japanese infants (11.1 +/- 3.0 mg/dl versus 8.0 +/- 2.2 mg/dl). This difference may be attributable to environmental and/or genetic factors.

Evaluation of change of cerebral circulation by SpO2 in preterm infants with apneic episodes using near infrared spectroscopy

Abstract Background : In the neonatal intensive care unit (NICU), hemodynamics in very low‐birthweight infants are generally examined for oxygen saturation (SpO2), heart rate, respiration rate, and blood pressure. The present study examined how changes in cerebral circulation in preterm infants can be evaluated by the SpO2 monitoring method with near infrared spectroscopy (NIRS) to detect the cerebral circulation.

Inhibitory Action of Bilirubin on Superoxide Production by Polymorphonuclear Leukocytes

To assess the interaction of bilirubin with albumin and to determine the site of bilirubin toxicity in cells, a study was made of the O2- production of neonatal neutrophils (PMNs) by two different stimulators: (1) concanavalin A (Con A) plus cytochalasin D (Cyt D), which acts on the cell surface, and (2) phorbol myristate acetate, which acts intracellularly. PMNs that had been separated from cord blood were incubated for 60 min at 37 degrees C in the solution with different molar ratios of bilirubin/albumin (unbound bilirubin, ranging from 0.35 to 3.92 micrograms/dl). The unbound bilirubin was determined by peroxidase oxidation method. A PMN viability of more than 96% was maintained after the incubation in each of solutions. The O2- production rate of PMNs stimulated by Con A plus Cyt D was inhibited in the presence of unbound bilirubin levels as low as 1.12 micrograms/dl, and the rate decreased as the levels of unbound bilirubin rose. The O2- production rate stimulated by Con A plus Cyt D was more remarkably inhibited than that by phorbol myristate acetate, which directly activates intracellular protein kinase C. These findings suggest that bilirubin toxicity to PMN can be shown at levels of unbound bilirubin as low as those in hyperbilirubinemic sera, and the critical site at which bilirubin exerts its toxicity is mainly in membrane level rather than on intracellular functions.

Effects of child seats on the cardiorespiratory function of newborns

Background : This study aims to determine the effect of differently positioned infant car seats on cardiorespiratory parameters in healthy full‐term newborns.

End‐tidal carbon monoxide is predictive for neonatal non‐hemolytic hyperbilirubinemia

Abstract Background : The aim of the present study was to evaluate the value of an end‐tidal carbon monoxide corrected for inhaled carbon monoxide concentration (ETCOc) at the early neonatal period. The value would be useful for predicting subsequent hyperbilirubinemia in non‐hemolytic full‐term infants.

Intracranial Hemorrhage and Vitamin K Deficiency Associated with Biliary Atresia: Summary of 15 Cases and Review of the Literature

Biliary atresia (BA) is a rare disease, characterized by progressive and obliterative cholangiopathy, and is one of the major causes of secondary vitamin K deficiency in infancy. We describe 15 infants (10 female, 5 male) with BA, presenting with intracranial hemorrhage (ICH), including 10 subdural hemorrhages, 4 subarachnoid hemorrhages, 2 intraventricular hemorrhages, and 1 intraparenchymal hemorrhage. The age at onset of ICH ranged from 26 to 79 (mean 54.2) days. Eight patients underwent successful surgical evacuation of ICH, following administration of vitamin K. All 15 patients underwent Kasai portoenterostomy for BA 8–30 days after onset. During a mean follow-up period of 86.8 (range 2–352) months, 4 patients died of liver failure despite lack of neurological sequelae. Two patients underwent living-related donor and 1 patient living-unrelated donor liver transplantation. Only 2 patients suffered neurological signs and symptoms, including mental retardation and epilepsy, whereas 3 were noted to have temporary hemiparesis which recovered completely during the follow-up period. The possibility of BA should be considered in the treatment of ICH due to vitamin K deficiency, since it is reported to be one of the major causes of secondary vitamin K deficiency. Urgent surgical intervention for ICH can be performed successfully following sufficient administration of vitamin K or fresh frozen human plasma. Moreover, early performance of Kasai portoenterostomy is possible even for patients who have undergone craniotomy.

Therapeutic indicators of acute encephalopathy in patients with complex febrile seizures

The aim of this study was to identify predictors of neurologic damage in children with febrile seizures or altered consciousness within 6 h of seizure onset.

Preventive effects of dexamethasone on hypoxic-ischemic brain damage in the neonatal rat

To clarify the preventive effects of glucocorticoid on perinatal hypoxic-ischemic (HI) brain damage, an experiment was carried out on 4-day-old rats pretreated for 4 consecutive days with 3 different regimens; namely, a low dose dexamethasone (Dex) (0.1 mg/kg/day), a high dose Dex (0.5mg/kg/day), and a saline administration. On the 7th postnatal day, after ligation of the left common carotid artery, the rats were exposed to 8% oxygen and decapitated on the 10th, 14th, 21st and 28th postnatal days. Ligated side brain damage was observed in 75, 7 and 3% of the rats in the saline, low and high dose Dex groups, respectively. However, a high mortality rate (42%) was noted in the high dose Dex group. The cumulative number of animals with poor outcome (death or brain damage) was 49 (80%), 13 (33%) and 24 (44%) in the saline, low and high dose Dex groups, respectively. On the 10th and 14th postnatal days, the rats in both the Dex groups showed delayed neuronal maturation and myelination in the non-ligated side motor cortex, however, these maturational differences disappeared on the 21st postnatal days. Otherwise, the number of cortical cells in both the Dex groups were significantly lower than that in the saline group on the 28th postnatal days (P < 0.05 in each). These findings suggest that the pretreatment with Dex protects the developing brain from HI injury through the suppression of the neuronal maturation. However, a decreased number of cortical cells may give rise to psychomotor retardation later.

Acrania: Report of the First Surviving Case

The first known surviving case of acrania is presented. The patient was the first child of a 29-year-old Japanese woman. Fetal ventriculomegaly was documented in the 35th gestational week. Prenatal sonography and magnetic resonance imaging suggested hydrocephalus with a wide encephalomeningocele. The baby was born at 38 weeks of gestational age by vaginal delivery. The patient had no calvarium, but did have a complete skull base with a partial defect in the occipital scalp and an underlying dural defect. Subsequently, the patient underwent repair of the scalp defect. At 3 months of age, after hydrocephalus developed, a subduro-peritoneal shunt was placed because of cosmetic and nursing problems. His developmental quotient was 10 at 3 years.

Acquired cytomegalovirus infection and blood transfusion in preterm infants

The urinary excretion of cytomegalovirus (CMV) DNA, amplified by polymerase chain reaction using two pairs of primers for late antigen (LA) and major immediate‐early antigen (MIE), and serum CMV IgM were examined in 85 pre‐term infants (birth‐weight less than 2000 g) on admission and monthly until 6 months after birth. Of these 85 infants, 27 had blood exchange transfusions (BET) and 28 had bolus blood transfusions two to nine times. Fifteen of 27 infants underwent BET with blood that had been filtered through Pall RC100 leukocyte removal filter; the other 12 with unfiltered blood. Neither urinary CMV DNA nor serum CMV‐specific IgM was detected at birth in any of the 85 pre‐term infants; during the first 6 months after birth urinary CMV DNA, for both MIE and LA, appeared in 22 of the 85 infants (25.9%) and CMV IgM was positive in 14 of the 85 (16.5%). Nine of the 12 (75%) infants who received BET of unfiltered blood showed a significantly higher prevalence of urinary CMV DNA compared to the infants in the other three groups (i.e., those who received no blood transfusion, those who had bolus blood transfusions, or those who received BET of filtered blood; P < 0.01 in each instance). In a logistic regression model, CMV, DNA urinary excretion was significantly associated with the mode of blood transfusion (unfiltered BET), and the Odds ratio was 38.9 (95% confidence interval, 9.4–160). There was no significant association with other independent variables such as gender, mothers seropositivity, gestational age, birth‐weight or delivery mode. In addition breast milk feeding was not likely to have influence on the high incidence of CMV infection among the infants who received the BET with unfiltered blood. In regions where the incidence of CMV seropositivity is high, as it is in the Japanese population, reduction of white blood cell and cellular blood components, such as platelets, through filtration is a convenient and effective way to successfully reduce the occurrence of acquired CMV infection in high‐risk neonates.