Neonatology

Artal, Raul; Doug, Nam; Wu, Paul; Sperling, Mark A.

doi: 10.1159/000242771pmid: 3370256

Previous studies have demonstrated impaired perinatal adaptation of glucose homeostasis with inappropriately low levels of catecholamines and glucagon in newborn infants born to diabetic mothers. To investigate whether these neonatal changes are related to maternal metabolic control, we sequentially measured plasma glucose, catecholamines and glucagon in the neonatal period in 10 infants born to well-controlled mothers with class B diabetes mellitus after uncomplicated pregnancies. Good glycemic control in the mothers resulted in appropriate counterregulatory hormone responses in the neonatal period, similar to those described in infants born to normal mothers. The significant rise in plasma epinephrine and glucagon paralleled the establishment of euglycemia, further suggesting that these hormones are important for perinatal adaptation of glucose homeostasis.

Tenenbaum, Denis; Gambert, Philippe; Meunier, Sylvie; D’Athis, Philippe; Nivelon, Jean Louis; Lallemand, Christian

doi: 10.1159/000242772pmid: 3370257

Serum lipoproteins were explored on the first day of life (D1) and on the sixth day (D6) in blood drawn by peripheral venipuncture from 43 normal term newborns, 22 breast-fed and 21 formula-fed, and were compared to those of a control group of 28 young adults. With the exception of apolipoprotein E (Apo E), values of lipoprotein components obtained at D1 were similar, although generally slightly lower than those previously reported for cord blood serum. Total Apo E concentration at D1 (71 ± 25 mg/l) was much higher than that obtained for the adult group (30 ± 7 mg/l). Apo E distribution within the lipoprotein spectrum confirmed the presence of an already known Apo E-rich high density lipoprotein subfraction, which was responsible for the high total Apo E level at birth. The rise of lipoproteins of low density from D1 to D6, as evidenced by the increase of very low density lipoprotein + low density lipoprotein cholesterol and low density lipoprotein apolipoprotein B concentrations, was shown to be diet dependent. It was significantly less important in newborns fed a standard formula moderately enriched in unsaturated fatty acids than in breast-fed newborns.

Okolo, Angela A.; Omene, Jackson A.; Scott-Emuakpor, Ajovi B.

doi: 10.1159/000242773pmid: 3370258

In the course of a systematic study of physiologic hyperbilirubinaemia, 200 Nigerian newborn infants were evaluated daily over a 12-day period. The pre-term and post-term neonates exhibited a distinct biphasic pattern of hyperbilirubinaemia. Mean peak bilirubin levels of 8.20 mg/dl for the pre-term, 7.15 mg/dl for the post-term and 8.34 for the term were attained on the fourth, third and fifth days, respectively. Term small for gestational age neonates experienced mean peak bilirubin levels of 7.02 mg/dl at the age of 4 days and maintained a sustained elevation for as long as the last day of the study. Higher values of physiologic hyperbilirubinaemia are observed in this study than has been reported for American neonates.

Okolo, A.A.; Okorodudu, A.; Glew, R.H.; Omene, J.A.

doi: 10.1159/000242774pmid: 3259437

Serum alpha-amylase activity was determined in 41 newborn infants with proven bacterial infections and compared to values obtained in 18 healthy control neonates. In the infected neonates serum alpha-amylase value, as determined by the blue starch method, was only 40% that of healthy controls; the mean value of 175.1 ± 64.9 IU/1 for healthy neonates was significantly higher (p < 0.0010) than the value of 82.8 ± 44.4 IU/1 for the infected neonates. Alpha-amylase levels did not correlate with severity of infections or mortality. The sensitivity and specificity of serum alpha-amylase level of 100 IU/1 were 75.6 and 94.7%; the positive and negative predictive values were 91.2 and 84.4%, respectively.

Zuppa, Antonio Alberto; Tornesello, Assunta; Papacci, Patrizia; Tortorolo, Giuseppe; Segni, Giuseppe; Lafuenti, Gianni; Moneta, Ernesto; Diodato, Annunziata; Sorcini, Mirella; Carta, Salvatore

doi: 10.1159/000242775pmid: 3370259

Hidalgo, Juan; Giralt, Mercé; Garvey, Justine S.; Armario, Antonio

doi: 10.1159/000242776pmid: 3370260

The present experiment was designed to examine the influence of pregnancy on basal and stress levels of serum and liver metallothionein (MT). Eighteen-day pregnant rats showed higher serum MT levels and lower liver MT levels than nulliparous rats, suggesting that a great MT mobilization from the liver into the serum was present in the former rats. Serum MT levels were not changed by either restraint or starvation. It is unlikely that the lower liver MT levels showed by pregnant rats were due to competition by progesterone for glucocorticoid receptors, as previously suggested, since the corticosterone/progesterone ratio was unchanged in pregnant rats. Liver MT response to food and water deprivation with or without restraint was somewhat different in nulliparous and pregnant rats. Thus, food and water deprivation for 24 h caused higher liver MT induction in pregnant than in nulliparous rats. When food and water deprivation was accompanied by restraint stress a further increase in liver MT was observed in nulliparous but not in pregnant rats. This suggests that food and water deprivation may be a more severe stress in pregnant rats because of the additional demands of the growing fetuses. Fetal liver MT was increased by restraint stress but not by food and water deprivation. The role of Zn influx into the liver is discussed.

Lassiter, Herbert A.; Christensen, Robert D.; Parker, Charles; Rothstein, Gerald

doi: 10.1159/000242777pmid: 3285898

Neonates are particularly susceptible to infection with Escherichia coli K1. To investigate the mechanisms which lead to this susceptibility, we examined: (a) the bactericidal activity of neutrophils; (b) opsonization, and (c) the bactericidal activity of serum in developing rats. Neutrophils from adult rats killed E. coli K1 more efficiently than did neutrophils from young animals. Opsonization of E. coli K1 by serum of prematurely delivered rats was poor. Serum from prematurely delivered and term rats promoted growth of E. coli K1, while serum from adult rats killed > 95% of the organisms within 90 min. However, the mixture of heat-inactivated serum from adult rats plus serum from prematurely delivered rats killed E. coli K1.

Maritz, Gert S.

doi: 10.1159/000242778pmid: 3370261

The effect of maternal nicotine exposure on lung growth in vivo in neonatal rats was investigated. Nicotine (0.25 and 1.0 mg/kg/day) administered subcutaneously to the pregnant animal from day 7 of gestation until weaning resulted in smaller neonatal lungs that were about 15% smaller on postnatal day 8. On day 21 no difference in lung mass occurs. Maternal nicotine exposure also causes enhanced lung cellular multiplication as judged by the calculated daily increase in DNA of 0.19 mg/g for control lung and 0.31 mg/g for experimental lung. Comparison of the protein/DNA ratio 5.75 ± 0.22 of the control and the 3.59 ± 0.21 of nicotine-exposed lungs showed that the cells of the latter was smaller. The lower lung mass was attributed to the smaller cell size. It is proposed that nicotine’s marked inhibitory (42%) effect on glycolysis probably results in type I cell injury and consequently enhanced cell proliferation.

Ramsay, T.G.; Hausman, G.J.; Martin, R.J.

doi: 10.1159/000242779pmid: 3370262

The influence of neural and endocrine status upon the metabolic activity and insulin responses of developing adipose tissue of fetal swine was examined. Central neural and endocrine regulation were removed by decapitation of fetuses at 45 days of gestation. Decapitated (decap) fetuses and intact littermates were removed at 65, 85 or 110 days of gestation. Fatty acid synthesis from glucose increased fivefold in slices of subcutaneous adipose tissue from intact fetuses and tenfold in tissue from decaps, between days 65 and 110 gestation. Insulin had minimal effects in intact tissue but stimulated glucose metabolism as early as 65 days of gestation in decap adipose tissue. Lactate was utilized for oxidation and fatty acid synthesis at rates as high or higher than glucose throughout gestation. These results indicate possible roles for lactate and insulin in producing the increased adiposity of decapitated fetal pigs reported previously. Secondly, the more active metabolism of decap tissue indicates that fatty acid synthesis in normal fetal adipose tissue is suppressed by development of inhibitory factors regulated by central mechanisms during late gestation.