bluuebunny/crossref_metadata_2025 huggingface dataset:
Serum and Lipoprotein Lipids of Fetal Pigs and Their Dams during Gestation as Compared with Man
Authors: Hentges Walsh , Martin R.J.
Published: September 2009

Serum and lipoprotein (LP) lipids were measured in fetal pigs and their dams during gestation. In the 2nd trimester (70 days of gestation), fetal lipids resembled those of their dams. Early in the 3rd trimester (90 days) total serum concentrations of cholesterol (CH), triglyceride (TG) and free fatty acids (FFA) were lower in fetuses than in sows (p < 0.01), but the decreases were not expressed uniformly among the LP classes. By the middle of the 3rd trimester (100 days) fetal serum lipids had declined further, and the distribution of TG (but not CH) between the LP fractions was significantly different from the distribution in sows (p < 0.01). Sow serum CH, TG and FFA varied, but did not change significantly from days 70 to 100 of gestation; there was a tendency for sow serum lipids to increase, particularly FFA. Distributions of TG and CH in sow LP were unchanged by pregnancy. Results suggest that independent fetal regulation of lipid metabolism develops during the last half of gestation, and that lipid metabolism (especially TG) may be altered during fetal life. Changes in sow lipids during gestation were much less pronounced than in humans, but fetal patterns were similar.
Effects of Chronic Maternal Dexamethasone Treatment on the Hormones of the Hypothalamo-Pituitary-Adrenal Axis in the Rat Fetus
Authors: Dupouy Jean-Paul , Chatelain Alain , Boudouresque Françoise , Conte-Devolx Bernard , Oliver Charles
Published: September 2009

Different hormones of the hypothalamo-pituitary-adrenal axis (corticotropin-releasing factor, adrenocorticotropic hormone, corticosterone) were measured in brain pieces (stalk, median eminence, hypothalamus), hypophyses, adrenals and plasma of 21-day-old rat fetuses from mothers which were given either plain tap water or water containing dexamethasone acetate (10 μg/ml) from day 15 to 21 of gestation. Dexamethasone induced drastic reduction of body weight (––66% vs. controls), severe atrophy of the adrenals (––83%) and a sharp drop in their corticosterone content (––74%). Fetal plasma corticosterone levels were below the lower limit of detection of the competitive corticosteroid-binding globulin (CBG) radioassay (< 0.01 μg/ml). Both atrophy and severe reduction of the adrenal activity in fetuses from dexamethasone-treated females were in good correlation with a drastic decrease in plasma adrenocorticotropic hormone (ACTH) levels which were below the lower limit of detection of the radioimmunoassay (RIA) used (< 10 pg/ml) and a significant reduction in pituitary ACTH content (––93%). The low corticostimulating activity of the fetal hypophyses was associated with a drop in both corticotropin-releasing factor (CRF) hypothalamic content (––57%) and concentration (––67%). The effects of dexamethasone on plasma and pituitary ACTH concentrations in 21-day-old fetuses were compared to those, previously reported, of encephalectomy and decapitation performed on day 16 of gestation. The reported data were consistent with the present results, suggesting both pituitary and hypothalamic sites for the in vivo inhibiting action of dexamethasone on the rat hypothaamic-pituitary-adrenal axis in late gestation.
High Levels of Group-Specific Component (Vitamin-D-Binding Protein) in the Cerebrospinal Fluid of Infants Aged < 2 Months
Authors: Katikaneni Lakshmi Pappu , Emerson David L. , Goldschmidt-Clermont Pascal J. , Loadholt Boyd C. , Levkoff Abner H. , Galbraith Robert M.
Published: September 2009

Because of the possible involvement of group-specific component (Gc) or vitamin-D-binding protein in the immunological functions of mononuclear cells and the increased risk of central nervous system infections in early infancy, we studied Gc levels in the cerebrospinal fluid (CSF) of children. CSFs were examined for the Gc concentration using ELISA and rocket immunoelectrophoresis, with purified Gc as standard. The results showed a significant inverse correlation (p < 0.05) between the age of the patients and CSF Gc levels. Gc levels in the CSF were significantly increased in infants < 2 months of age (12.5 μg/ml), as compared to infants > 2 months (1.7 μg/ml, p < 0.0028). In children > 2 months of age a significant correlation was found between Gc levels and those of other CSF proteins (albumin, IgG and total protein, p < 0.002). However, no significant correlation between Gc levels and those of other CSF proteins was apparent in infants < 2 months of age, indicating the possibility that the concentration of Gc in the CSF may be selectively increased in this age group.
Action of Acetaldehyde on Glucose Metabolism of Newborn and Adult Erythrocytes
Authors: Ninfali Paolino , Palma Fulvio , Piacentini Maria Piera , Fornaini Giorgio
Published: September 2009

This paper reports the effect of acetaldehyde on erythrocytes (RBC) of human adults and newborns. Acetaldehyde increases glucose consumption in adult RBC, but has no effect on that of newborn RBC. The compound stimulates the hexose monophosphate shunt and decreases the pyruvate production of the two RBC suspensions. In newborn RBC, acetaldehyde slightly modifies triose-P and fructose-1,6-bisphosphate but has no effect on the ATP/ADP ratio and glucose-1,6-bisphosphate content, which change markedly in adult RBC. Analysis of aldehyde dehydrogenase reveals nearly one half of enzyme activity in newborn RBC. The data indicate that in both adult and newborn RBC, acetaldehyde causes an intracellular reduced state, but the newborn cells take advantage of their greater pyruvate production for complete removal of the exceeding NADH equivalents.
Gastric Proteases in the Human Infant
Authors: Henschel Michael J. , Newport Michael J. , Parmar Veena
Published: September 2009

The electrophoretic mobilities of proteases present in gastric juice taken within 10 h of birth from 5 healthy, premature infants were compared with calf chymosin, pig pepsin A and human adult gastric juice. The juice from 2 infants contained predominately a chymosin-like enzyme, another had almost exclusively pepsins similar to those of the adult juice, while the other two contained a mixture of both. The pepsins consisted of two elements, probably pepsin A (EC 3.4.23.1), and pepsin C (EC 3.4.23.3). Single radial immunodiffusion gave a definite reaction to calf anti-chymosin serum in five samples taken from a further 17 infants. These results indicate that some human infants secrete chymosin. The reaction in the immunodiffusion assay indicated a much lower enzyme activity than that implied from electrophoretic separations. It is suggested that species differences resulted in poor cross-reactivity of the antiserum.
Cardiovascular Status during Ketamine Anesthesia in the Fetal Lamb
Authors: Lafond Josée S. , Fouron Jean-Claude , Bard Harry
Published: September 2009

To determine the effects of maternal ketamine anesthesia on fetal hemodynamic and cardiac function, a study was carried out on 8 chronically catheterized fetal lambs. Ketamine was administered intravenously to the mother every 15 min during 1 h. The fetal PO2 and pH remained within physiological limits whereas the PCO2 decreased from 44.35 ± 1.36 to 37.32 ± 4.75 Torr (p < 0.05). The following changes of the fetal heart systolic time intervals were observed: a progressive lenghtening of the preejection period (PEP) (from 52 ± 10 to 63 ± 11 ms, p < 0.01), a shortening of the ejection time (ET) and a significant increase of the PEP/ET ratio (from 0.32 ± 0.04 to 0.47 ± 0.01, p < 0.01). The two components of PEP, electromechanical delay and the isovolumetric contraction time were both prolonged. A progressive rise of fetal systolic and diastolic pressures was also noted (p < 0.01). Fetal heart rate increased (145 ± 33 to 190 ± 28 beats/min, p < 0.01) and cardiac beat-to-beat variability decreased (from 0.028 to 0.009, p < 0.01) during the ketamine anesthesia. This study demonstrates that maternal anesthesia with ketamine can alter indices of fetal myocardial function and other cardiac parameters used in fetal and neonatal monitoring, without affecting tissular oxygenation.
Protein Metabolism and Postnatal Growth in Very Low Birthweight Infants
Authors: Micheli Jean L. , Schutz Yves
Published: September 2009

Due to the development of new ‘bedside’ investigative methods, relatively abstract physiologic concepts such as energy cost of growth, efficiency of protein gain, metabolic cost of protein gain and protein turnover have been quantified in very low birthweight infants. ‘Healthy’ premature infants expend about 30% of their energy to cover the metabolic cost of growth. Stable isotope techniques using 15N- (or 13C)-labeled amino acids gave a new insight into this very high energy demanding process represented by the protein accretion in growing tissues. It has been demonstrated that the rate of protein synthesis (10–12 g/kg/day) greatly exceeds that necessary for net protein gain (2 g/kg/day). The postnatal growth and protein metabolism have different characteristics in ‘healthy’, ‘sick’ or ‘intrauterine undernourished’ very low birthweight infants.
Occurrence and Significance of Riboflavin Deficiency in Preterm Infants
Authors: Lucas A. , Bates C.J.
Published: September 2009

Few studies have explored the importance of riboflavin deficiency in premature infants. Infants receiving human milk during the first 2 weeks become biochemically riboflavin-deficient, partly through photodegradation of riboflavin during the banking and delivery of human milk. Animal studies have shown that the metabolic lesions of riboflavin deficiency in sucking neonates differ in important ways from those seen later after weaning. Techniques are described for non-invasive study of functional riboflavin requirements by premature infants. It appears prudent to supplement human milk-fed babies with at least 300 μg riboflavin/day; but the potential danger of over supplementation in infants exposed to phototherapy is discussed.
Effect of Maternal Nicotine Exposure on Growth in vivo of Lung Tissue of Neonatal Rats
Authors: Maritz Gert S.
Published: September 2009

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.
Metabolic Development of Porcine Fetal Adipose Tissue
Authors: Ramsay T.G. , Hausman G.J. , Martin R.J.
Published: September 2009

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.
Use of Experimental Models to Study the Development of Renal Function
Authors: Fukuda Yutaka , Larsson Stefan , Celsi Gianni , Lechene Claude , Aperia Anita
Published: September 2009

By use of animal experiments it has been demonstrated that renal cells are immature at birth. Membrane transport is quantitatively and qualitatively different. The control of fluid and electrolyte balance is therefore different in infancy. The increased filtered load at birth as well as hormones will induce tubule maturation. The use of animal experiments will in the future give an insight into how external factors influence growth and maturation.
Renal Response to Vasopressin in Premature Infants: What Is New?
Authors: Sulyok Endre
Published: September 2009

Clinical and experimental data indicate that the neonatal pituitary is capable of responding with arginine vasopressin (AVP) release to physiological stimulation and pathological events commonly seen in the perinatal period. The limited concentrating performance of the newborn kidney is thought, therefore, to be accounted for by the diminished end-organ responsiveness to AVP and the inability of the immature kidney to generate and maintain deep corticopapillary osmotic gradient. Evidence has been provided to indicate that in low birth weight premature infants the impaired renal tubular sodium transport, the renal salt wasting and late hyponatremia, and the increased renal prostaglandin production may be important factors in attenuating renal response to AVP.
Effect of Total Parenteral Nutrition on Lipase Activity in the Stomach of Very Low Birth Weight Infants
Authors: Mehta Nitin R. , Liao Teresa H. , Hamosh Margit , Smith Yolande F. , Hamosh Paul
Published: September 2009

Lipase activity was quantitated in gastric aspirates of 7 premature infants (gestational age 24–29 weeks) during periods of total parenteral nutrition (TPN), mixed parenteral nutrition and gavage feeding or exclusive gavage feeding. The infants were studied from birth until the establishment of exclusive gastric gavage feeding. Lipase activity in gastric aspirates (quantitated by the hydrolysis of 3H-triolein at pH 4.2 and expressed in nmol 3H-oleic acid released/min/ml gastric aspirate) did not differ significantly as a function of mode of feeding: 570 ± 235 during TPN, 260 ± 145 during mixed parenteral nutrition and gavage feeding, and 374 ± 149 during exclusive gastric gavage feeding. The data suggest that, contrary to the intestine and pancreas, the digestive function of the stomach is not impaired during TPN in the very preterm infant.
Pepsin and Its Multiple Forms in Early Life
Authors: Adamson I. , Esangbedo A. , Okolo A.A. , Omene J.A.
Published: September 2009

Pepsin and its multiple molecular forms have been studied in pre-term and post-term Nigerian infants. The levels of total enzyme activity and acidity were lower in the pre-term infants when compared to term and post-term infants. Resolutions of the various species by ion-exchange chromatography and electrophoresis revealed that the development of specific isoenzymes in term infants occurred towards the end of the neonatal period. Differential development of the enzyme and the isoenzyme in the neonatal period may have important clinical bearing on the subsequent pancreatic protease hydrolysis which may provide a basis for evaluating gastric capacity for nutritional management of these infants.
Prenatal Development of the Brattleboro Rat Is Influenced by Genotype and Lysine Vasopressin Treatment of the Mother
Authors: Snijdewint F.G.M. , Boer G.J. , Swaab D.F.
Published: September 2009

Homozygous (Hom) Brattleboro rats suffer from severe diabetes insipidus (DI) as a consequence of the lack of arginine-vasopressin (AVP) in the brain. Compared with heterozygous (Het) AVP-synthesizing Brattleboro rats, Hom rats show disturbed body and brain development. In this study breeding experiments with Het and Hom rats were performed to determine whether prenatal conditions might contribute to the developmental disturbances in Hom pups. For this purpose Het and Hom females were mated with Hom and Het males, respectively. In addition lysine-vasopressin (LVP) was administered to half of the pregnant females, since this has previously been shown to stimulate birth weight of Hom pups. On day 1 postnatally the body and brain weight of Hom pups of nontreated Hom mothers was significantly smaller than that of the Het litter mates, whereas no difference was found between the weight of Het or Hom pups of nontreated or LVP-treated Het mothers. These results indicate an important role of the genotype of the mother in prenatal development of Hom pups. LVP administration failed to diminish the growth deficits, but increased protein and DNA content of the cerebellum of both Het and Hom pups. Notwithstanding the improved prenatal growth of Hom pups from Het mothers, postnatally retarded development was still observed: at 1 month of age there was a significant difference between the body, brain and cerebellar weight of Het and Hom pups from Het mothers. It was therefore concluded that the prenatal situation of the Hom mother, i.e. AVP-deficiency, significantly contributes to the developmental disturbance of the Hom pup, but also that growth impairment is linked to the presence of the mutation in the Hom pups themselves.
Early Development of the Thyroid Axis in the Brattleboro Rat
Authors: Huffman Linda , Hedge George A.
Published: September 2009

Plasma concentrations of thyrotrophin (TSH), thyroxine (T4), and triiodothyronine (T3), and pituitary TSH concentrations were determined at weekly intervals during the first 42 days following birth in Brattleboro homozygous (DI), Brattleboro heterozygous (HZ), and Long-Evans (LE) rats. Offspring from matings of Brattleboro rats were divided into DI and HZ animal subgroups on the basis of hypothalamic vasopressin content. In control LE rats, circulating levels of TSH, T4, and T3, and pituitary TSH concentrations increased during the early postnatal period to reach relatively stable levels between 28 and 42 days of age. In DI and HZ rats, the thyroid axis developed in parallel to that of LE rats during initial postnatal weeks. However, by 42 days of age, pituitary TSH concentrations were clearly elevated in Brattleboro rats relative to levels in age-matched LE animals. These data indicate that differences in thyroid axis function between Brattleboro and LE rats occur only after the attainment of a degree of maturity.
Vitamin D Metabolism in Preterm Infants: Effect of a Calcium Load
Authors: Delvin E.E. , Salle B.L. , Glorieux F.H. , David L.S.
Published: September 2009

Decrease in serum calcium level leading to hypocalcemia during the first week of life is a frequent finding in premature neonates. Eight premature neonates presenting with such an episode of hypocalcemia in the course of their first 4 days of life were studied. They were fed with a phosphate-enriched human milk and given vitamin D3 (2,100 IU/day per os). We have evaluated the effect of a 24-hour pharmacologic calcium infusion on the circulating levels of calcium, inorganic phosphate, magnesium, 25-hydroxycalciferol (25-OHD), 1α,25-dihydroxycalciferol [1,25(OH)2D] and immunoreactive parathyroid hormone (iPTH). After the infusion, circulating iPTH and Pi levels dropped significantly (p < 0.025 and p < 0.005 respectively) whereas serum Ca and 25-OHD (p < 0.005) increased. Mg and 1,25(OH)2D serum levels remained unchanged. Our data show that an increased calcium supply sustained for 24 h induces an appropriate response in iPTH secretion. Effects on circulating levels of 1,25(OH)2D were variable and probably reflected individual differences in half life of 1,25(OH)2D or in set points in the feedback mechanisms involved in the control of 1,25(OH)2D synthesis.
Development of the Rat Hepatic Microsomal Glucose-6-Phosphatase System and Its Glucocorticoid Inducibility
Authors: Burchell Ann , Leakey Julian E.A.
Published: September 2009

Rat liver glucose-6-phosphatase activity was determined in both fully activated and intact microsomal preparations during perinatal development. Activities increased rapidly in both preparations following birth, then gradually fell to adult values. The latency of the glucose-6-phosphatase system also increased neonatally whereas hepatic glycogen concentrations decreased postnatally. The effect of dexamethasone pretreatment on the hepatic glucose-6-phosphatase system was also investigated. Dexamethasone pretreatment failed to decrease the latency of glucose-6-phosphatase in microsomes from neonatal rats but decreased the latency of the enzyme in adult female rat liver from 44 to 12% of total activity.
Perinatal Brain Serotonin Metabolism in Rats Malnourished in utero
Authors: Manjarréz Gabriel , Chagoya Graciela , Hernández Jorge
Published: September 2009

The fetal brain serotonin metabolism has been studied in two types of gestationally malnourished rats: protein-calorie and after ligation of one branch of the uterine artery. The results showed an elevation of L-tryptophan and serotonin content and an enhancement of tryptophan-5-hydroxylase activity in the malnourished fetal brain, continuing up to day 10 of postnatal life. The possible implications of these early changes of the serotoninergic system in brain differentiation and a lasting change in tryptophan-5-hydroxylase kinetics are proposed for further study.
Effect of Indomethacin on Cerebral Blood Flow Velocity of Premature Newborns
Authors: Laudignon N. , Chemtob S. , Bard H. , Aranda J.V.
Published: September 2009

Using the Doppler technique, the effect of therapeutic doses of indomethacin on the cerebral blood flow velocity (CBFV) of anterior cerebral arteries was studied in 13 preterm infants with patent ductus arteriosus. The first intravenous injection of indomethacin (0.2 mg/kg, group 1, n = 10) induced a significant decrease in the area under the velocity curve at 15 min (––22%), which was sustained until 120 min (––28%, p < 0.005). In contrast, no significant change in CBFV occurred after the third dose (group 2, n = 7). In both groups, capillary blood gases, mean arterial blood pressure, and heart rate remained stable throughout the study. In 5 mechanically ventilated infants, the increase in CBFV secondary to suctioning was significantly attenuated after the first dose of indomethacin (p < 0.02) but not after the third (p = 0.56). Thus, an initial dose of indomethacin may attenuate CBFV increases secondary to clinical manipulations in the preterm newborn.
Perinatal Mortality in Belgium
Authors: De Wals P. , Bertrand F. , Verlinden M. , Beckers R.
Published: September 2009

Perinatal mortality in Belgium remains high compared with other countries of Western Europe, although a marked decrease was observed during the period from 1956 to 1984. Analysis of the death causes indicates that further progress is feasible. Social inequalities and geographic variation are persisting in spite of the long-established policy of social welfare and free access to health services. Most of the studies on perinatal mortality in Belgium are descriptive and based on data recorded in birth and infant death certificates. In the future, alternative sources of information should be used to analyze more precisely and to understand more clearly the interactions between the different determinants of perinatal mortality and to evaluate the impact of social and health services.
Randomized Trials of Perinatal Interventions in Belgium and Europe
Authors: Alexander S.
Published: September 2009

Using statistics from United Nations Demographic Yearbooks (1958–1983) and the Oxford Database of Perinatal Trials, a survey of perinatal randomized control trials (RCTs) during the last 25 years in Europe was performed. Total number of trials has been related to average annual population, average annual total births and average annual total of medical doctors. There is a clear geographical trend; Finland, Denmark, Sweden, Ireland and the United Kingdom in the leading group produce, on average, 50 times as many randomized trials as socialist countries other than Hungary and the German Democratic Republic. Within Belgium itself, similar disparities are observed: university A has produced twice as many RCTs as all the other universities pooled together. For Belgium, the introduction of multicenter trials may be reversing this situation, and uptake of ongoing multicenter trials seems homogeneous within the country.
Stimulation by 17α-Hydroxyprogesterone of Glycoprotein and Glycosaminoglycan Synthesis in Human Placenta in vitro
Authors: Burton Albert , Lockhart Florence , Bosnjak Slavica , Yong Stephen
Published: September 2009

The incorporation of 14C-glucosamine into glycoproteins (GP) and glycosaminoglycans (GAG), of 3H-leucine into protein, and the hexuronic acid (HA) content of polymerized GAG was determined in incubated placental tissue. In placentae of earlier gestational age (GA), incorporation of 14C-glucosamine was 2.6 times greater than others at 38–39 weeks GA. 19 of 26 placentae at 38–39 weeks GA responded by one or more parameters when incubated with 0.5–3 μM 17α-OH-progesterone (17OHP). Those which did not respond were all of earlier GA; the placental content of GAG decreased in these from 31.1 ± 1.8 nmol HA/mg protein to 16.4 ± 1.5 nmol in placentae of GA 38–39 weeks. In the latter, 17OHP increased GAG by 42.5 % to 24.4 ± 2.5 nmol HA/mg protein in a 2-hour incubation. Progesterone, oestriol, cortisol and testosterone were without effect. It is concluded that synthesis of placental GAG decreases toward the end of gestation, but can be increased by 17OHP specifically. This indicates that 17OHP is a biologically active steroid and might have a role in maintaining placental function.
Sensitivity of the Renal Adenylate Cyclase Receptor System to Parathormone during the Last Third of Pregnancy in the Rat
Authors: Gugi B. , Mallet E.
Published: September 2009

During the last third of pregnancy, the rat phospho-calcic metabolism is clearly modified. Sensitivity of the renal receptor to parathormone (PTH) was investigated over this period in the fetuses and their mothers. As early as day 16.5 of pregnancy, the fetal kidney is sensitive to bovine PTH (1–34) on the basis of cAMP production. Sensitivity declines on the last day of pregnancy. The newborn kidney showed a higher response to PTH 3 h after birth than after 24 h. The basal adenylate cyclase activity in renal membranes of maternal kidney does not change. The sensitivity to PTH and to fluoride both decreased on day 18.5. A desensitization process of the PTH receptor A-C system has to be studied in order to explain these results.
Cholesterol Metabolism in Infant Rats, Effect of 6-Hydroxydopamine and Guanfacine
Authors: Hahn P. , Srubitski L.
Published: September 2009

Infant rats (10–16 days) and weaned animals (older than 18 days) were treated with drugs inhibiting β-adrenergic activity and were sacrificed 4 days later. 6-Hydroxydopamine acts on postsympathetic nerve fibres, and guanfacine stimulates α2-receptors. Both drugs caused a rise in plasma cholesterol and a decrease in hepatic 3-hydroxy-3-methylglutaryl CoA reductase activity in infant but not in weaned animals. The activity of acylcholesterol acyl CoA transferase, on the other hand, was decreased after drug administration. Thus, both antihypertensive drugs may cause changes in cholesterol metabolism, especially in infant animals.
Free Tryptophan Decrease in Jaundiced Newborn Infants during Phototherapy
Authors: Zammarchi E. , La Rosa S. , Pierro U. , Lenzi G. , Bartolini P. , Falorni S.
Published: September 2009

Tryptophan and nonesterified fatty acids (NEFA) are bound to serum albumin. NEFA displace tryptophan from their binding sites. Since NEFA decrease during phototherapy, we examined reciprocal variations of NEFA, total and free tryptophan in jaundiced newborn infants during phototherapy. After 24 h of phototherapy, we noticed a significant decrease of both NEFA and free tryptophan (p < 0.001). Free tryptophan variations might affect the synthesis of cerebral neutrotransmitter 5-hydroxytryptamine, which depends on the passing of free tryptophan through the blood-brain barrier.
Urinary and Blood Levels of Adenosine 3′,5′-Monophosphate, Phosphorus and Calcium in Infants
Authors: Weintraub Z. , Iancu T.C. , Sheinfeld M. , Kraiem Z.
Published: September 2009

The changes during the first year of life in urinary and nephrogenous cAMP levels were determined in 152 normal, full-term infants using spot urine samples. The use of spot tests simplifies considerably the logistics of the cAMP determination which can be used for the investigation of parathyroid function. Levels of urinary and nephrogenous cAMP (expressed both as a function of creatinine excretion as well as glomerular filtration rate) rose from birth to 1 year of age, whereas plasma cAMP levels did not change significantly. Levels of cAMP (both urinary and nephrogenous) were significantly correlated with age, length, weight, and urinary phosphorus concentrations of the infants. No significant correlation could be observed, however, between serum phosphorus or serum and urinary calcium on the one hand, and urinary or nephrogenous cAMP on the other.
Daily Sequential Changes in Plasma Atrial Natriuretic Factor Concentrations in Mechanically Ventilated Low-Birth-Weight Infants
Authors: Liechty Edward A. , Johnson Michael D. , Myerberg David Z. , Mullett Martha D.
Published: September 2009

Plasma atrial natriuretic factor (ANF) concentrations are elevated in mechanically ventilated infants. To test the hypothesis that changes in pulmonary compliance affect ANF cncentration, we measured plasma ANF concentrations sequentially in low-birth-weight, ventilated infants who either received surfactant replacement or placebo on day 1. ANF concentrations were elevated as compared to adult controls on day 1 and increased significantly on days 2 and 3 before declining. Day 5 concentrations were not different from day 1. Several infants had ANF concentrations greater than 1,280 pg/ml on days 2–4. There were no significant differences in ANF concentrations between surfactant-treated and non-treated infants on any day. ANF concentrations increased in parallel with changes in salt and water balance, but no significant relationships were apparent between absolute ANF concentrations and parameters of salt and water balance. The results suggest that ANF secretion is elevated in infants with pulmonary disease. While the temporal relationship between the initial rise in ANF concentration and increase in salt and water excretion suggest that ANF is involved in this diuresis, the role it may play is unclear from the present data.
Sexual Differentiation of the Gonads and of the Reproductive Tract
Authors: Wilson Jean D.
Published: September 2009

Between 1947 and 1952 Alfred Jost deduced that sexual differentiation is an ordered process in which chromosomal sex determines gonadal sex and gonadal sex in turn directs the development of phenotypic sex. This powerful formulation has been substantiated by both genetic and endocrine evidence and has had a profound impact on clinical medicine as well as on biology. The means are now at hand for dissecting the molecular mechanisms by which genetic determinants and regulatory factors interact in this cascade to produce the male and female phenotypes.
Effects of Sulfisoxazole, Hypercarbia, and Hyperosmolality on Entry of Bilirubin and Albumin into Brain Regions in Young Rats
Authors: Hansen Thor Willy Ruud , Øyasœter Stephanie , Stiris Tom , Bratlid Dag
Published: September 2009

We have studied the entry of 3H-bilirubin and 125I-albumin into brain regions in young rats during short-term (1 h) hyperbilirubinemia. Bilirubin enters the brain both under control, displacer (sulfisoxazole 50 mg/kg), hypercarbic (PCO2 18–21 kPa; pH ≈ 6.9), and hyperosmolar (serum osmolality ≈ 400 mosm/l) conditions. No significant differences in bilirubin uptake were found between brain regions. Thus preferential staining of basal ganglia (Ê»kernicterus’) may not be a phenomenon related to uptake. Albumin does not cross the blood-brain barrier under control or displacer conditions, but does enter the brain to some extent in hypercarbia, and to a greater extent in hyperosmolality. During control and displacer conditions, only unbound bilirubin appears to enter the brain. In hypercarbia bilirubin enters primarily in the unbound form, but some is also albumin-bound. In hyperosmolality a significant fraction of the bilirubin entering the brain is albumin-bound.
Free and Bound Tryptophan in Human Milk during Early Lactation
Authors: Zanardo V. , Bacolla G. , Biasiolo M. , Allegri G.
Published: September 2009

Total (protein-bound and free) and free tryptophan levels of breast milk were evaluated in 10 mothers of term infants on the 3rd, 4th, 5th, and 30th day of lactation. We found high levels of both total and free tryptophan in the colostrum. This variation in tryptophan content of breast milk may reflect the requirement of the human neonate.
Histological Changes in the Placenta Induced by Maternal Alcohol Consumption in the Rat
Authors: Eguchi Yasunobu , Yamamoto Masako , Arishima Kazuyoshi , Shirai Mitsuyuki , Wakabayashi K. , Leichter Joseph , Lee Melvin
Published: September 2009

To investigate the placental enlargement which accompanies maternal alcohol consumption during pregnancy, Sprague-Dawley rats were given 20% ethanol for 4 weeks prior to mating and 30% ethanol throughout gestation. Pair-fed controls received an isocaloric amount of corn starch and chow, with water ad libitum, and ad libitum controls received rat chow and water. On days 17, 18, 19 and 20 of gestation, placentas were removed for histological observation. On days 18–20, the placentas of alcohol-fed rats weighed significantly more than did those of controls, although there was no difference in weight on day 17. Giant cells in the basal zone were significantly increased in number and size in alcohol-fed rats compared to controls. Trophoblastic cells in the basal zone were significantly larger in the alcohol group than in the control groups except on day 17. The maternal blood channels in the labyrinth were wider and more filled with blood corpuscles in the alcohol group than in either control group. It is concluded that the increased weight of the placenta may be largely due to the stagnated maternal blood cells in the labyrinthine blood channels and also to the increased number and size of giant cells and the enlarged trophoblastic cells in the basal zone.
Effects of Rocking on Neuromuscular Development in the Premature
Authors: Clark David L. , Cordero Leandro , Goss Karen C. , Manos Diane
Published: September 2009

It has been postulated that motion stimulation accelerates postnatal development. To test this hypothesis, 26 premature infants participated in a randomized controlled study of the effects of rocking on body weight gain and measures of neuromuscular development. Treatment infants were exposed to 15-min sessions of sinusoidal oscillation about the longitudinal axis, three times a day for 2 weeks. Infants were evaluated at the beginning and end of the 2-week treatment period and 2 weeks later. Neuromuscular development at these three times was measured with the comprehensive Dubowitz examination. Following treatment, large as compared with small premature infants showed a marked, but not statistically significant increase in weight gain. Duration of treatment appears to be a critical factor in influencing weight gain. All infants exposed to motion stimulation showed significant gains over controls in overall neuromuscular development. Passive muscle tone (posture, arm recoil and popliteal angle) and active motility (arm traction, head lag and ventral suspension) showed significant improvement in the treatment group at posttest. Similar results were recorded with auditory and visual orientation, alertness and defensive reaction. These specific areas of behavior have been recognized to be delayed in premature infants not exposed to a program of sensory stimulation.
Alpha-Fetoprotein and Albumin Uptake by Mouse Tissues during Development
Authors: Laborda Jorge , Naval Javier , Calvo Miguel , Lampreave Fermin , Uriel José
Published: September 2009

We have studied the evolution of the incorporation of alpha-fetoprotein (AFP) and albumin by mouse tissues from fetal to adult life. Mice were injected with 125I-labelled AFP or albumin and, 3 h later, blood and organs were removed and analyzed for their radioactive protein content. Results showed that all immature tissues examined took up both AFP and albumin from blood. AFP uptake was higher during fetal and early postnatal life and decreased with age. In general, the relative uptake of albumin was lower than that of AFP, and the time-course incorporation of both proteins was parallel in brain, liver and kidney. In other tissues such as white adipose tissue, brown adipose tissue and skin, AFP uptake decreased while albumin uptake remained almost constant or increased with age. In the fetal period, the strong AFP uptake in white adipose tissue contrasted with the much lower albumin incorporation by this tissue. Autoradiographs from sections of organs and entire animals confirmed the cytoplasmic localization of AFP and albumin. We conclude that AFP and albumin found in developing tissues, except for fetal liver and yolk sac, proceed mostly from blood uptake. These results agree with recent experimental data suggesting that the major physiological role of AFP is the transport and delivery of polyunsaturated fatty acids to developing tissues.
Categorization of Near-Term Mouse Fetuses According to Their Viability as a Tool for Developmental Toxicity Screening
Authors: Pinto-Machado J.
Published: September 2009

In 1,015 CD-1 near-term mouse fetuses, removed by cesarean section after cervical dislocation of dams, skin color, motility, crying, and breathing were studied. Three categories of fetuses were considered: living and surviving (92.5%); living but non-surviving (6.9%), and stillborn (0.6%). Particular attention was paid to the following: 24 fetuses, still apneic after routine manipulation, started breathing by specific maneuvers; 5 of these 24 fetuses were apparently dead when apnea recovery was successfully tried, and the living but non-surviving category must be considered in developmental toxicity screening as prenatal injuries may be manifested by an increase in the incidence of the fetuses belonging to this category.
Postnatal Development of Enzyme Activities Associated with Protection against Oxidative Stress in the Mouse
Authors: Harman Andrew W. , McKenna Marshall , Adamson Gregory M.
Published: September 2009

A number of enzyme systems are important in the protection of cells from chemical-induced oxidative damage. Little is known of the relative importance of these enzymes during postnatal development and it is possible that changes in their activity during this period may alter the susceptibility to toxic agents. This study investigated the activities of glutathione peroxidase, glutathione reductase, catalase, superoxide dismutase, γ-glutamylcysteine synthetase and glutathione synthetase in the liver, lung and kidney of postnatal and adult mice. The first 3 postnatal weeks are characterized by marked changes in the activities of enzymes that protect against oxidative stress (glutathione peroxidase/reductase, catalase and superoxide dismutase). Overall, the activity of these enzymes suggests that the mouse has a higher level of protection against peroxides at various stages during this period but lower capacity to detoxify superoxide anions. The activities of the glutathione-synthetic enzymes (γ-glutamylcysteine synthetase and glutathione synthetase) were significantly lower in the kidney of the postnatal mice, but the liver and lung had levels similar to those in the adult. Glutathione turnover in the liver of 2-week-old mice was not different from that in adults. The results indicate a complex pattern of development in the activities of detoxification enzyme systems during postnatal development.
Altered Maternal Thyroid Function: Fetal and Neonatal Myocardial Metabolism
Authors: Kumar Ratan , Chaudhuri B.N.
Published: September 2009

The influence of the maternal thyroid status on the fetal and neonatal myocardial protein, carbohydrate and lipid metabolism was studied in rats. The neonates born of hypothyroid mothers could not survive beyond 8 days after birth. The offsprings born of hypothyroid mothers showed growth retardation, decreased level of heart mitochondrial protein, reduced myocardial free fatty acid (FFA) oxidation at birth and afterwards, low glucose oxidation by the heart at later fetal stages, and afterwards, despite low heart glycogen reserve, glucose oxidation was high. The offsprings born of hyperthyroid mothers showed stimulation in overall growth, increased myocardial FFA oxidation and increased 14C-glucose incorporation into glycogen as well as increased myocardial glucose oxidation during fetal stages. Results indicate that maternal thyroid hormones play an important role in the metabolic control of fetuses and neonates.
Development of Peroxisomal β-Oxidation Activities in Brown Fat of Perinatal Rabbits
Authors: Mangurian Luz P. , Donaldson Robert P.
Published: September 2009

The development of peroxisomal activities in brown fat was analyzed in perinatal rabbits, 25- and 30-day fetuses, newborns, 5- and 10-day-old pups. Purified peroxisomal fractions were obtained from brown fat homogenates by sucrose gradient centrifugation at a density of 1.22 g/cm3. Enzymes specifically associated with the isolated peroxisomes, acyl-CoA oxidase, catalase and KCN-insensitive β-oxidation, were most active in 25-day fetuses and much less active after birth. Mitochondrial-associated activities such as cytochrome c oxidase were greatest at birth. The β-oxidation enzymes, enoyl-CoA hydratase, β-hydroxy-acyl-CoA dehydrogenase, and thiolase were present in mitochondrial as well as peroxisomal fractions. Nevertheless, the levels of hese three enzymes in peroxisomes were higher in fetuses. Thus, peroxisomes, in contrast to mitochondria, were most active prior to birth. This suggests that peroxisomes do not participate in rown fat thermogenesis but that they have some role in priming the development of brown fat in perinatal rabbits.
Human Cord Blood Lymphocytes Do Not Simultaneously Express CD4 and CD8 Cell Surface Markers
Authors: Reason Donald C. , Ebisawa Motohiro , Saito Hirohisa , Nagakura Toshikazu , Iíkura Yoji
Published: September 2009

Several authors have reported finding significant numbers of immature T lymphocytes of the CD4/CD8 ‘double positive’ phenotype in human cord blood. We have studied over 30 cord blood samples using directly conjugated reagents and have failed to detect such cells in any of the samples. Differences in staining methodologies that may account for this discrepancy are discussed.
The Ability of Granulocytes to Generate Superoxide Anions and Hypochlorite during Phagocytosis: Comparison of Neonatal Granulocytes with Adult Granulocytes
Authors: Nishida Akira , Kimura Hirokazu , Sugioka Katsuaki , Nakano Minoru
Published: September 2009

The ability of granulocytes to generate superoxide anions (O2) and hypochlorite (OCL––) during phagocytosis was investigated using peripheral blood samples from adults and cord blood samples from neonates, using the chemiluminescence probe cypiridina luciferin analog (CLA) for O2 generation and luminol (L) for OCl–– generation. OCl–– generation by granulocytges was also monitored by taurine chloramine formation. The chemiluminescence probe based upon CLA was highly specific for and sensitive to O2 and could be adopted to determine O2 generation in terms of xanthine oxidase units. The CLA-dependent chemiluminescence by cord blood granulocytes was significantly higher than that by normal adult granulocytes. Taurine chloramine formation was significantly correlated with the Independent chemiluminescence (L-CL). Thus, the L-CL is considered to be mainly involved in OCl–– generated by phagocytizing granulocytes. L-CLs by cord blood granulocytes and normal adult granulocytes were essentially the same during phagocytosis.
Regulation of Hepatocyte-Specific Gene Expression in Cultures of Human Embryonic Hepatocytes
Authors: van Roon M.A. , Zonneveld D. , de Boer P.A.J. , Moorman A.F.M. , Charles R. , Lamers W.H.
Published: September 2009

The aim of this study was to see whether the rat embryo can serve as a model system for hepatocyte-specific gene expression in the human embryo. Carbamoylphosphate synthetase was used as a hepatocyte-specific marker molecule. Despite the earlier developmental appearance of this enzyme in human than in murine liver, the hormonal regulation of gene expression in cultures of embryonic hepatocytes was found to be the same. Therefore, a relatively early developmental appearance of regulatory hormones rather than differences in regulatory mechanisms of gene expression appears to be responsible for the early accumulation of the enzyme in human liver, when compared to murine liver.
Effect of Sympathetic Nervous System on Cerebral Blood Flow in the Newborn Piglet
Authors: Monin Pierre , Feillet François , Hascoet Jean-Michel , Vert Paul
Published: September 2009

The role of the sympathetic nervous system on cerebral blood flow (CBF) autoregulation was evaluated in newborn piglets. Six animals were studied after ablation of the right superior sympathetic ganglion and compared to 6 control animals. Mean arterial blood pressure (MABP) was decreased by successive blood withdrawal and CBF was measured by radioactive microspheres. In denervated animals, MABP and CBF correlated positively according to a parabolic curve showing an absence of autoregulation when MABP is above 50 mm Hg (y = 0.079x2 –– 5.9x + 154, p < 0.01). In control animals, CBF remains stable throughout the experiment (y = 0.28x + 5). These data suggest a shift to the left of the upper limit of the autoregulation range in denervated animals and consequently a poor adaptation to increased MABP.
Regional Circulatory Responses to Hindlimb Work in Developing Swine
Authors: Buckley N.M. , Frasier I.D.
Published: September 2009

Circulatory effects of hindlimb work were studied in 29 swine (aged 1 day to 1 month) anesthetized with pentobarbital. Femoral, renal and intestinal blood flow, resistance and autoregulatory capability were determined at different levels of hindlimb oxygen consumption before and during distal sciatic nerve stimulation. Increases in oxygen consumption were accompanied by hyperemia at all ages, but by increased oxygen extraction only in 2-week and 1-month-old animals, without evidence of autoregulation. Blood flow was consistently redistributed from the kidney and small intestine only in neonates. Older animals generally sustained autoregulation of renal and intestinal blood flows throughout experiments. We concluded that hindlimb work evokes age-related adjustments in regional blood flow that reflect the balance of neural and autoregulatory control.
Plasma Cortisol Distribution in the Pig from Birth to Six Weeks of Age
Authors: Kattesh H.G. , Charles S.F. , Baumbach G.A. , Gillespie B.E.
Published: September 2009

Plasma levels of cortisol and percent distribution of cortisol among protein-bound (corticosteroid-binding globulin (CBG) and albumin) and unbound forms were measured in naturally born/conventionally reared pigs from birth to 6 weeks of age. Total cortisol and percent unbound cortisol were highest in pigs at birth and decreased (p < 0.01) in a linear fashion over the sampling period. Percent CBG-bound cortisol was lowest on days 3–21 relative to the peak value seen on day 42. However, actual CBG-bound cortisol was not different after day 1. Percent albumin-bound cortisol was highly correlated with percent CBG-bound cortisol (r = ––0.90; p < 0.001). These results suggest that a rapid shift in cortisol distribution from unbound and albumin-bound forms to that which is bound to CBG occurs by approximately day 28 of age in the neonatal pig.