Absorption and metabolism of glycerin in the neonatal period. I. Speed of turnover of glycerin during continuous intravenous infusions in newborn infants of various gestational ages and in older infants]

Glycerol was infused intravenously over 2 hours in preterm and term appropriate-for-date and in term small-for-date infants at the age of 12 to 72 hours and 10 to 14 days and in infants at the age of 3 to 8 months. The dosage was 0.25.kg-1.h-1 and 0.5.kg-1.h-1, respectively. Less than 6 per cent of the glycerol injused were recovered in the urine irrespective of the dosage. The total clearance was 9.1 to 14.6 ml.kg-1. min-1 during the first weeks of life with 0.25 g.kg-1.h-1 glycerol irrespective of gestational age and intra-uterine growth retardation; and it rose to 31.8 ml.kg-1.min-1 in older infants. With 0.5.kg-1.h-1 glycerol the total clearance values were lower in all groups. The glucose blood level and the blood lactate concentration as well as the parameters of the acid-base-balance were not significantly influenced by glycerol.     

Ketonic bile acids in urine of infants during the neonatal period

Ketonic bile acids have been found to be quantitatively important in urine of healthy infants during the neonatal period. In order to determine their structures, the bile acids in urine from 11 healthy infants were analyzed by gas-liquid chromatography-mass spectrometry (GLC-MS) and three samples with particularly high levels of ketonic bile acids were selected for detailed studies by ion exchange chromatography, fast atom bombardment mass spectrometry, microchemical reactions, and GLC-MS. The major ketonic bile acid was identified as 7 alpha, 12 alpha-dihydroxy-3-oxo-5 beta-chol-1-enoic acid, not previously described as a naturally occurring bile acid. The positional isomer 7 alpha, 12 alpha-dihydroxy-3-oxo-4-cholenoic acid, recently described as a major urinary bile acid in infants with severe liver diseases, was also excreted by most infants. Three acids related to cholic acid were identified: 7 alpha, 12 alpha-dihydroxy-3-oxo-, 3 alpha, 12 alpha-dihydroxy-7-oxo-, and 3 alpha, 7 alpha-dihydroxy-12-oxo-5 beta-cholanoic acids. Five bile acids having one oxo and three hydroxy groups were also present. Based on mass spectra and biological considerations two of these were tentatively given the structures 1 beta, 7 alpha, 12 alpha-trihydroxy-3-oxo- and 1 beta, 3 alpha, 12 alpha-trihydroxy-7-oxo-5 beta-cholanoic acids. Some of the others had a hydroxy group at C-4 or C-2. The levels of ketonic bile acids were higher on the third than on the first day of life, and lower after 1 month. The formation and excretion especially of 3-oxo bile acids is proposed to result from changes of the redox state in the liver in connection with birth.     

Chromosome anomalies of infants dying during the perinatal period and premature newborn

Summary 363 samples of different tissues were taken for cultivation from 118 antepartum deaths, 85 intrapartum deaths and 112 newborn dying during the first days after delivery. Successful growth of culture was noticed in 48.2% (15.4%) of antepartum deaths; 71.8% of intrapartum deaths and 68.1% of newborn dying during the first days of life. Among the 22 antepartum deaths 3 (13.6%) infants were found to have anomalies of karyotype; among 61 intrapartum deaths 3 (4.9%) infants were found to have karyotype anomalies; and among 92 early neonatal deaths 6 ones (6.5%) had karyotype anomalies. The total frequency of chromosome anomalies among the infants dying during the perinatal period was 6.9%.The final result of cytogenetic investigation of 607 premature infants was that chromosome anomalies were found among 2.5%, that is 3.5 times as much, as in the general newborn population. Among the types of chromosome anomalies the main defects were anomalies in the system of sex chromosomes and trisomy-21, and that is the proof of the fact, that other types of anomalies, found in newborn populations lead to earlier lethality.     

Characteristics of the functional state of erythrocytes in healthy full-term newborn infants

The hematological parameters and functional status of erythrocytes were studied using osmotic and ammonium load in healthy newborns and adults. The mean erythrocyte volume in newborns was greater than in adults. Significant differences in the osmotic fragility index in newborns were observed upon the transition from swelling to hemolysis. The erythrocyte hemolysis kinetics in the ammonium load was studied by small-angle light scattering using a LaSca analyzer. The percentage of erythrocyte hemolysis was smaller and the rate of hemolysis in newborns was by a factor of 2.5 lower than in adults.     

Dynamics of alpha-fetoprotein concentration in mice of different genotypes during the neonatal period]

A comparative assay of the alpha-fetoprotein (alpha-FP) level in mice of various genotypes (CBA, C3H, C57BL/Se/Sn, BALB/c, CC57W, AKR and nude--nu/nu) was conducted in the course of 3 weeks of postnatal period. The concentration of alpha-FP reached the following levels: the first day 2(-10)-2(-9); the 5th day 2(-8); the 8th day 2(-7); the 15th day 2(-4); on the 22nd day the level was zero. Nude mice which showed the alpha-FP concentration of 2(-2) on the 15th day were an exception. A conclusion was drawn that the alpha-FP synthesis was based not on the athymia of nude mice per se, but upon other unknown factors.     

Pituitary somatotropic function of newborn infants]

The content of the hypophysial somatotrophic hormone was studied in the blood of cord vessels at parturition and in the peripheral blood of newborn infants during the first 2 hrs and 1-9 days of life. The hormone level by the periods of 2 hrs was markedly lower than in the foetuses, it sharply increased by the end of the first day and gradually decreased during the subsequent days. The functioning of the hypothalamic-hypophysial system in humans during this period is discussed.     

A diagnostic survey of infants referred for chromosome analysis in the neonatal period.

Examination and assessment of 140 liveborn and stillborn infants referred within two weeks of birth for chromosome analysis showed that 48 had Down''s syndrome, 12 other chromosome abnormalities, 17 single gene disorders, 18 recognisable anomalads, 8 recognisable syndromes of unknown aetiology, and the remainder were undiagnosed. Of the non-Down''s cases that were diagnosed, 21% had a chromosomal abnormality. These results suggest that a request for chromosome analysis in the newborn period should be viewed as one step in syndrome identification.