bluuebunny/crossref_metadata_2025 huggingface dataset:
Noradrenaline Appearance in Guinea Pig Brown Adipose Tissue
Authors: Cresteil Thierry
Published: September 2009

A rapid growth of the guinea pig brown adipose tissue occurred during the last third of fetal life. Endogenous noradrenaline was measurable from day 55 of gestation and rose until birth. The maximal noradrenaline concentration was achieved on the first day of extrauterine life and remained constant during the postnatal period. So, noradrenaline was present in brown adipose tissue at birth and could mediate the neonatal nonshivering thermogenesis activation as suggested in the discussion.
Decreased Alpha-Fetoprotein Concentration in Neonatal Pigs after Injection of Adult Swine Serum
Authors: Carlsson Roland N.K. , Ingvarsson Bengt I.
Published: September 2009

Repeated intraperitoneal injections of adult swine serum lead to reduced concentrations of α-fetoprotein (AFP) in neonatal pigs. This is interpreted to be due to suppression of the synthesis of AFP by a factor(s) present in the serum of adult swine although its mode of action remains unclear.
Fetal and Placental Growth in the Rat following Differential Reduction of Litter Size
Authors: Croskerry P.G. , Smith O.K. , Hall S. , Shepard B.J.
Published: September 2009

The effects on fetal and placental growth of differential litter size reduction on day 10 (LR10) and day 13 (LR13) were determined in the rat. LR10 resulted in significant increments in placental weight, fetal body and brain weight, and brain protein content in the survivors at day 21. A marginal effect on brain cellularity (DNA) was observed. Values for these parameters generally followed the extent of reduction. Placenta weight was also related to original litter size. In contrast, LR13 which was associated with survival of supernumerary placentae (those without a fetus) produced no growth enhancement. Prenatal development was discussed in terms of general systemic influences and hormonal regulatory mechanisms.
Maternal Plasma α-Feto-Protein in Pregnancies Terminating in Spontaneous Abortion
Authors: Habib Zacharias
Published: September 2009

The value of measuring maternal α-feto-protein in predicting an eventual pregnancy wastage was assessed. When pregnancies terminated in spontaneous abortion, maternal plasma α-feto-protein levels were statistically lower than in pregnancies with viable, healthy offspring.
Materno-Fetal Transport of Creatine in the Rat
Authors: Davis Barbara M. , Miller Richard K. , Brent Robert L. , Koszalka Thomas R.
Published: September 2009

The transfer of 14C-creatine to the rat fetus was studied following continuous i.v. infusion into the mother. In the presence of a relatively constant maternal plasma 14C-creatine concentration, creatine was accumulated by the chorioallantoic placenta and visceral yolk sac to concentrations higher than that found in maternal or fetal plasma. The ability of the extraembryonic membranes to accumulate creatine changed during gestation; nevertheless, these membranes concentrated creatine against a gradient throughout the period studied (14–22 days of gestation). Neither 14C-creatinine nor 14C-urea were concentrated in the placentae or fetal plasma when compared to maternal plasma. Simultaneous infusion of β-guanidinopropionic acid with 14C-creatine reduced both movement and accumulation of creatine into the fetoplacental unit. It is concluded that the accumulation of creatine by the chorioallantoic placenta and by the visceral yolk sac is an active process with creatine diffusing down its concentration gradient into the fetal circulation.
The Effects of Glucose and Alanine Infusion on Urea Production and Gluconeogenesis in the Starved Newborn Guinea Pig
Authors: Ogata Edward S. , Holliday Malcolm A.
Published: September 2009

We studied the effects of glucose, alanine, and saline infusion in newborn guinea pigs. After acute (24–30 h after delivery) or prolonged (96–100 h after delivery) starvation, alanine or glucose infusion significantly increased liver glycogen concentration. Alanine infusion increased plasma glucose concentration and urea production rate (UrP). After acute starvation, a continuous 12-hour glucose infusion did not affect either plasma alanine concentration or UrP; however, after prolonged starvation, glucose infusion significantly reduced both variables. After prolonged starvation, the newborn guinea pig mobilizes alanine for gluconeogenesis. Increased protein catabolism is a consequence of this process. Glucose infusion negates the need for gluconeogenesis and spares body protein.
Longitudinal Studies of Infants with the Wilson-Mikity Syndrome
Authors: Saunders R.A. , Milner A.D. , Hopkin I.E.
Published: September 2009

Simple clinical measurements were performed on a group of 23 very low birth weight babies (< 1500 g and < 32 weeks gestation), and combined with pulmonary function studies in 13 cases. The studies included a special single-breath analysis, or Tidal Resistance Profile, which enabled us to detect air trapping. 2 infants developed classical Wilson-Mikity syndrome and 2 further infants exhibited a milder, shorter form of the same disorder. All 4 survived. Results suggest that all infants in this maturity group are at risk of developing Wilson-Mikity syndrome, and that it comprises a wide spectrum of respiratory dysfunction.
Sucrase and Lactase Synthesis in Suckling Rat Intestine in Response to Substrate Administration
Authors: Raul F. , Simon P.M. , Kedinger M. , Grenier J.F. , Haffen K.
Published: September 2009

The intestinal brush border disaccharidases separated by gel electrophoresis were studied after oral administration of a high sucrose or lactose diet to 11-day-old suckling rats during 3 days. Some modifications of the brush border protein and enzyme patterns could be attributed to the effect of the basic diet: increase of glucoamylase, appearance of a weak sucrase activity and of a second molecular form of maltase. However, the specific action of a given disaccharide on the synthesis of the corresponding hydrolytic enzyme could be clearly demonstrated. Indeed, the electrophoretic pattern after sucrose or lactose feeding showed a marked increase of the protein bands corresponding to sucrase-isomaltase or lactase activities.
Influence of pH and Temperature on Behaviour of Surfactant from Human Neonatal Lungs
Authors: Meban C.
Published: September 2009

The surface pressures of human surfactant films were measured under static conditions and under dynamic (expansion-compression) conditions. The results from both methods showed that the maximum surface pressures generated by surfactant films in vitro were strongly dependent on temperature throughout the range 29–41 °C, higher pressures being achieved at the lower temperatures. In contrast, increasing the pH of the subphase stepwise over the range 7.1–7.7 produced a modest fall in the maximum pressures exerted by the films. The possibility that surfactant films may behave in a similar manner in vivo is discussed.
Perinatal Changes in Glycolytic Function in Response to Hypoxia in the Incubated or Perfused Rat Heart
Authors: Hoerter J.A. , Opie L.H.
Published: September 2009

Glycolysis was assessed in the rat heart during the perinatal period: in the fetus of 16.5 days postcoitum (dpc) and 21.5 dpc (term = 22 dpc) and in the newborn of 1 day postpartum (dpp) and 7 dpp. Glucose uptake, lactate production and glucose incorporation into glycogen were much higher in the fetal than in the newborn heart. Measurements were made of tissue contents of high energy phosphate compounds, lactate and hexose phosphates. Unchanged contents of glucose-6-phosphate and fructose-6-phosphate during hypoxia in spite of an increased flux through the enzyme phosphofructokinase (PFK) suggest that PFK has a regulatory role in the glycolysis as early as 16.5 dpc. The isolated fetal heart was more resistant to hypoxia than the newborn heart: glucose uptake and lactate production were much higher and high energy phosphate compounds and glycogen were better maintained in the fetal heart.
Effects of the Teratogenic Folic Acid Antagonist, 9-Methyl Pteroylglutamic Acid on Uronic Acid Levels in Fetal Rat Limbs
Authors: Paynton B.V. , Schmidt R.R. , Cotler J.M.
Published: September 2009

Experimental pregnant rats were placed on a transitory folic acid-deficient regimen, i.e. dietary restriction of folic acid plus the teratogen and folic acid antagonist, 9-methyl pteroylglutamic acid; a regimen resulting in multiple congenital skeletal malformations. Controls received a folic acid-supplemented regimen. Accumulation of a primary component of the extracellular matrix, glycosaminoglycans (GAG), was quantitatively evaluated by measuring uronic acid concentrations in fetal limbs. On days 16 and 18 of gestation, fetal limbs were removed, pooled from each litter, and prepared for uronic acid, protein, and DNA quantitation. The treatment results in (1) a decreased rate of protein and DNA accumulation prior to day 16 of gestation, the rate not being affected from day 16 to day 18 of gestation; (2) a trend toward an increased rate of uronic acid accumulation prior to day 16 of gestation, and (3) a decreased rate of uronic acid accumulation from day 16 to day 18 of gestation. Furthermore, our observations confirm our earlier suggestion that there is a decreased rate of accumulation of some nonprotein component(s) in fetal limbs obtained from folic acid-deficient mothers from day 16 to day 18 of gestation.
Long-Lasting Effect of Single Ecdysone Injections in Newborn Rats
Authors: Csaba G. , Darvas Zsuzsanna , László Valéria , Juvancz I. , Vargha P. , Bodrogi L. , Fehér T.
Published: September 2009

Single injections of ecdysone to newborn rats were followed by increases in the weights of the adrenals and decreases in the weights of the thymuses in the adults. No change was registered in body weights and in the weights of the gonads. The plasma androsterone levels seemed to decrease; however, the interindividual differences proved to be too great to draw definite conclusions.
Salicylamide Glucuronide Formation in Newborn Babies with G-6-PD Deficiency
Authors: Meloni Tullio , Costa Sinfarosa , Corti Rachele , Cutillo Stefano
Published: September 2009

Salicylamide glucuronide formation has been studied in 23 newborn babies with erythrocyte G-6-PD deficiency and in 15 normal newborns on the first day of life. Glucuronide formation was significantly lower (p < 0.001) in the former in comparison with the controls. In the newborns with G-6-PD deficiency who subsequently became hyperbilirubinemic an even lower mean glucuronide formation was observed (p < 0.01) in respect to the non-jaundiced G-6-PD-deficient newborns.
Particulate and Free Hexokinase in Fetal Rat Liver
Authors: Hommes F.A. , Everts R.S.
Published: September 2009

The association of hexokinase with particulate fractions of liver has been studied during the development of the rat. In the fetal rat liver about 50% of the total hexokinase is bound to the mitochondria. This proportion decreases gradually afterbirth. No association of hexokinase with mitochondria could be demonstrated in the adult rat liver. It is suggested that the binding of hexokinase to the mitochondria is a consequence of a property which is lost during development of the mitochondrial membranes. At least part of the hexokinase is rather tightly bound to the mitochondria. Glucose-6-phosphate or ATP do not solubilize the enzyme. The proportion of hexokinase bound to the mitochondria is independent of the metabolic state of the hepatocyte as exemplified by studies with inhibitors of oxidative phosphorylation, using the digitonin technique for the separation of particulate and cytosol fractions of isolated fetal rat hepatocytes.
Evolution of Fibrinogen Levels in Rat Fetal and Maternal Blood during Gestation
Authors: Legrèle C. , Félix J.M. , Droulle-Bertignon C. , Potron G. , Jacquot R.
Published: September 2009

Plasma fibrinogen levels increase during the last third of gestation in the pregnant rat. In the fetus, they are barely measurable at 18 days, increase rapidly thereafter and reach adult values just before birth, in a matter of 3 days.
The Effects of Thyroid Hormones on Myelination in the Developing Rat Brain
Authors: Freundl Kathleen , Van Wynsberghe D.M.
Published: September 2009

Rats radiothyroidectomized 1 day after birth received daily subcutaneous injections of 1 μg/l0 g body weight of thyroxine (T4) or an equimolar amount of triiodothyroacetic acid (T3AC) from day 6 through day 25. The number of myelinated axons, myelinated axon area, and area of the myelin sheath in the corpus striatum were investigated. Hypothyroid neonates demonstrated a normal number of myelinated axons with a decrease in the area of these axons. T4 treatment resulted in an increased number of smaller axons while T3AC treatment produced fewer but larger axons than the T4 treatment. The myelin area changed as the axon area changed with the myelin thickness remaining constant in all groups.
Effects of Pharmacologic Agents on Umbilical Blood Flow in Fetal Lambs in utero
Authors: Berman jr. William , Goodlin Robert C. , Heymann Michael A. , Rudolph Abraham M.
Published: September 2009

We studied the effects of pharmacologic agents on umbilical blood flow and umbilical-placental vascular resistance in 18 fetal lambs in utero. Three groups of drugs were identified: the first had no effect on umbilical blood flow or umbilical-placental vascular resistance; the second altered umbilical blood flow secondary to changes in heart rate and placental perfusion pressure, but did not change umbilical-placental vascular resistance; the third decreased umbilical blood flow and increased umbilical-placental vascular resistance. The studies suggest mechanisms by which umbilical blood flow is regulated in the fetal lamb.
The Supply of Citrate to the Sheep Fetus
Authors: Fenton Enid , Britton K.G. , Nixon † D.A.
Published: September 2009

In situ placental perfusion has been used to study the role of the sheep placenta in fetal citrate metabolism. The perfusate citrate concentrations rose steadily to values higher than in fetal plasma. This rise was not influenced by intravenous administration of citrate to the ewe. Concentration and electropotential gradients indicate that transplacental passage is unlikely and the rise is probably due to placental synthesis. However, the quantity of citrate supplied to the fetus was calculated to be small compared with the fetal metabolic rate. Comparison with the guinea pig shows close similarity in fetal plasma concentrations and the amount of citrate formed per unit weight of fetus.
Pituitary Adrenocortical Response to Stress during the First Day of Post-Natal Life in the Rat
Authors: Corbier P. , Roffi J.
Published: September 2009

During the first hours of post-natal life, the newborn rat does not respond to ether stress by a rapid increase of ACTH secretion. Ether inhalation by 5- and 12-hour-old animals slightly but significantly increases plasma and adrenal corticosterone levels, but only 30 min after the onset of stress. At 1 day of age, adrenal response is established. The adrenal cortex of 5-hour-old animals responds normally to an intraperitoneal injection of 25 mU of ACTH. These results indicate that there is an absolute stress non-response period in newborn rats which is followed by a relative stress non-response period. The lack of response is not due to an organic block of the adrenal cortex, but could be due to the accumulation of elevated levels of corticosterone in the central nervous system.
Cardiovascular Reactivity of Neonatal and Adult Sheep to Autonomic Stimuli during Adrenergic Depletion
Authors: Woods, jr. J.R. , Dandavino A. , Nuwayhid B. , Brinkman, III C.R. , Assali N.S.
Published: September 2009

The cardiovascular responses of the neonatal and adult sheep to autonomic agonists and antagonists were studied in the resting state and following adrenergic neuronal depletion with reserpine. Both the neonates and adults showed similar supersensitivity of the effector system of the peripheral circulation to alpha adrenergic stimulation with catecholamines. In addition, the neonates exhibited supersensitivity of the myocardial effector system to β-adrenergic stimulation. Unusual finding was a marked supersensitivity of the heart and peripheral circulation to cholinergic receptor blockade with atropine, the mechanisms of which are as yet unclear.
Basic Cardiovascular Parameters in the Underweight Neonatal Swine
Authors: DeRoth Laszlo , Downie H.G.
Published: September 2009

Some hematological and cardiovascular parameters of the underweight neonatal piglets have been compared with normal-weight 1 and 7-day-old swine (Sus scrofa domestica). The underweight swine had a significantly lower leukocyte count, plasma protein level and blood glucose level, but a significantly higher plasma LDH level. Heart rate and arterial blood pressure were significantly lower in the underweight group. Based on the observed results it was postulated that the piglets born with a low body weight could also be physiologically immature since the cardiovascular parameters measured approximated those reported for normal fetuses of the same weight. Further studies are required to ascertain if a functional immaturity persists in the neonatal animals.
Perinatal Development of the Tyrosine Oxidizing System
Authors: Coufalik Alena , Monder Carl
Published: September 2009

The enzymes of the tyrosine oxidase (TO) system of rat liver were measured during pre- and postnatal development. At all ages, the rate of tyrosine oxidation was limited by the activity of tyrosine aminotransferase (TAT). TAT of liver was undetectable from 4 days to 1 day before birth and was lower than p-hydroxyphenylpyruvate oxidase (pHPPO) and homogentisate oxidase (HO) postnatally. At birth, TAT, pHPPO, and HO were 2.9, 13, and 40% of adult values, respectively. Relative levels in fetal liver were HO > pHPPO » TAT. When enzyme activities were adjusted to compensate for dilution by hematopoietic cells, absolute activities increased, but other relationships remained the same. pHPPO rose at 15–17 days after birth and exceeded adult values at 31 days. HO was unchanged after birth. We conclude that each enzyme of TO follows a unique developmental path, with no concerted control of the entire TO system.
Cerebral Oxidative Metabolism during Intrauterine Growth Retardation
Authors: Brown J.D. , Vannucci R.C.
Published: September 2009

Cerebral oxidative metabolism during intrauterine growth retardation was investigated utilizing a pregnant-rat model. Dams were subjected to unilateral uterine artery ligation on the 17th day of gestation. At term, they were sacrificed by decapitation and the fetuses delivered by cesarean section. Body and brain weights of fetuses from ligated uterine segments were smaller than those of offspring from nonligated horns of the experimental rats or those from sham-operated dams. Blood glucose at birth was reduced by 25% in growth-retarded fetuses. Cerebral oxidative metabolites, including glycogen, glucose, lactate, ATP, and phosphocreatine, were not different from control levels. These findings suggest that neither tissue hypoxia nor deficient glucose delivery to brain can account for the stunted cerebral growth observed in fetuses following uterine artery ligation.
Effect of Feeding on the Cessation of Transport of Macromolecules by Enterocytes of Neonatal Piglet Intestine
Authors: Leary, jr. Harvey L. , Lecce James G.
Published: September 2009

To elucidate further the role of digesta in the cessation of transport of macromolecules to the blood by enterocytes of neonatal piglet small intestine, a portion of the ileum was surgically isolated and vented to the exterior. The ability of this isolated intestine to transport macromolecules was compared with that of the intestine remaining in the digestive pathway in the same piglet. The isolated intestine ceased transporting macromolecules at the same time as the intestine in the digestive pathway, thus implicating a humoral signal that is responsible for the cessation of transport.
Integrated Cardiovascular Responses to Combined Somatic Afferent Stimulation in Newborn Piglets
Authors: Gootman P.M. , Buckley N.M. , Gootman N. , Crane L.A. , Buckley B.J.
Published: September 2009

Heart rate, mean aortic pressure and arterial flow responses to interactions of afferent stimulation of the sciatic (SNS) and median nerve of the brachial plexus (BNS) were studied in 30 newborn piglets under halothane-N2O anesthesia. High frequency or intensity SNS or BNS stimulation resulted in pressor responses accompanied by significant increases in the femoral flow and carotid and renal resistance. Combined stimulation produced responses smaller than the estimated sum of the responses. Low frequency or intensity SNS or BNS resulted in depressor responses accompanied by significant decreases in mean femoral flow without change in heart rate; combined stimulation produced responses smaller than the estimated sum. When pressor and depressor patterns of stimulation were combined, pressor responses always dominated. The absence of facilitation to any combination of interactions implies that the cardiovascular regulatory system is not fully developed at birth and undergoes, therefore, postnatal maturation.
Influence of Increasing Age on Lethality Induced by Carbon Monoxide or Hypoxic Hypoxia
Authors: Winston Joseph M. , Roberts Robert J.
Published: September 2009

Mice ranging in age from 2 to 150 days of age were exposed to 2,000 ppm carbon monoxide (CO) or 7.5% O2. 2-day-old mice were more resistant than older animals to the lethal effects of both CO and hypoxic hypoxia. The oldest age group (150 days) were also found to be more resistant than young adult mice to the lethal effects of both CO and hypoxic hypoxia. The role of body temperature in the age-dependent susceptibility was studied by altering the environmental temperature. Neonatal mice remained resistant to the lethal effects of CO until the environmental temperature reached 35 °C at which time the death rate of neonatal mice equaled that of the adult mice in 30 °C environment.
In vivo Demonstration of Renal Carbonic Anhydrase Activity in the Fetal Lamb
Authors: Robillard Jean E. , Sessions Christine , Smith, jr. Fred G.
Published: September 2009

The capacity of the fetal renal carbonic enzyme to facilitate the renal reabsorption of bicarbonate was studied in 8 long-term fetal lamb preparations (103–124 days of gestation). After acetazolamide administration the fetal arterial blood pH and PC02 values decreased significantly (p < 0.05). Significant increases in fetal urinary pH (p < 0.001), and urinary excretion of bicarbonate (p < 0.001), potassium (p < 0.05) and total cation (Na+ + K+) were observed after carbonic anhydrase inhibition. It is suggested from these in vivo studies that renal carbonic anhydrase is present and active during fetal life and does not limit the capacity of the fetal kidney to reabsorb bicarbonate.
Cold Stress Influence on Lung Lecithin in the Newborn Rabbit
Authors: Mims LeRoy C. , Pascale James A.
Published: September 2009

Term, food-water deprived newborn rabbits exposed to a cold environment for 48 h demonstrated a significant decrease in total lung lipid (p < 0.01), total triglyceride (p < 0.001), total phospholipid (p < 0.05), and total phosphatidylcholine (p < 0.025). Disaturated phosphatidylcholine remained unchanged. Fatty acid methyl esters of total and disaturated phosphatidylcholine were not influenced by cold stress. Likewise, there was no alteration in pulmonary function as determined by deflation pressure-volume relationships.
The Response of Adult Rats Weaned Prematurely and Normally to Starvation
Authors: Hahn P. , Koldovský O.
Published: September 2009

Male rats were weaned normally (NW; day 30 after birth) or prematurely (PW; day 18) to a Purina Chow diet. Serum cholesterol levels and the activities of some enzymes of fatty acid and glucose metabolism were determined when the animals were 6 and 10 months old and, in the older group, also after 2 days of starvation. Blood cholesterol levels rose with age and at 10 months were higher in PW than NW rats. This difference disappeared after starvation. Hepatic pyruvate kinase (PK) activity was the same in fed NW and PW animals but was significantly higher in starved PW than NW rats. Hepatic phosphoenolpyruvate carboxykinase (PEPcK) activity was lower in NW than in PW rats, but this difference disappeared on starvation. In white fat, starvation caused a fall in PEPcK activity in both groups. In general, the effect of starvation did not accentuate the differences between the two groups. However, PEPcK activity in white fat increased with age about fourfold.
Synthesis of Arachidonic Acid in the Human Placenta in vitro
Authors: Zimmermann T. , Winkler L. , Möller U. , Schubert H. , Goetze E.
Published: September 2009

The syntheses of arachidonic acid and total fatty acids were measured in human placentas at the end of the first trimester and at term using 14C-acetate in in vitro incorporation experiments. The rates of arachidonic acid synthesis were determined to be 0.70 (first trimester) and 0.64 (term) μmol/h/100 g of placental tissue. The calculated rates of total fatty acid synthesis amount to 0.5 (first trimester) and 0.6 (term) μmol palmitate-equivalents/h/100 g. The results suggest that the human placenta seems to be not dependent on maternal arachidonic acid. Near term the placenta even could be a source of arachidonic acid.
Glycosylation of Mouse Embryonic Hemoglobins in Cultured Yolk Sac Erythroblasts
Authors: Malik Z. , Djaldetti M.
Published: September 2009

Embryonic hemoglobins of yolk sac nucleated erythroblasts were glycosylated in vitro by (3H)-glucose and the rate of glycosylation was maximal within 24 h of incubation. Isoelectric focusing of the glycosylated products revealed that both EI and EII embryonic hemoglobins have glycosylated components, EIg, EIIg, with pi very close to the native hemoglobins.
Dynamics of Glucose-Induced Plasma Insulin Increase in the Rat Fetus at Different Stages of Gestation
Authors: Kervran A. , Randon J. , Girard J.R.
Published: September 2009

The effect of glucose on the release of insulin from the pancreas of 19.5- to 21.5-day-old rat fetuses has been studied in utero. Fetal hyperglycemia was induced by a square-wave glucose infusion into pregnant rats over a period of 150 min. The infusion of glucose raised the fetal blood glucose concentration to that of the mother and induced a rapid increase of plasma insulin levels on day 19.5 of gestation. There was a progressive rise of the insulin response as the gestation proceeded, with an increase of the two phases of the hormonal secretion. Maternal hypothermia induced by pentobarbital anesthesia decreased markedly the insulin response to hyperglycemia in the mothers and their fetuses. In fetuses decapitated on day 18.5 and studied on day 21.5, the increase of plasma insulin concentration after a 1-hour hyperglycemia was similar to that in the littermate control fetuses.
Electrokinetic Behaviour of Cord Blood Platelets in Acidosis: an in vitro Study
Authors: Kosztolányi Gy. , Jobst K.
Published: September 2009

The effect of acidosis on platelet surface potential was studied in vitro in samples obtained from newborn infants. It was found that acidosis induced by CO2 and lactic acid decreased the electrophoretic mobility of platelets in the presence of plasma. It is suggested that the changed electrokinetic properties of platelets in acidosis may be an additional factor contributing to bleeding manifestations and thrombotic complications often seen in babies with perinatal asphyxia.
Maternal Plasma Alpha-Feto-Protein in Missed Abortion
Authors: Habib Zacharias
Published: September 2009

Maternal plasma α-fetoprotein (AFP) levels in 8 pregnancies, which several weeks later ended as missed abortions, were evaluated. In 7 patients, blood sampling before or after the death of their fetuses revealed almost normal maternal AFP values. The relatively viable placenta of missed abortion probably hampers the eventual leakage/transudation of fetal AFP into maternal circulation.
Correlations between Neonatal Body Weight and Adolescent Brain Development in Rats
Authors: Zamenhof Stephen , Ahmad Gulzar , Guthrie Donald
Published: September 2009

Correlations between neonatal body weight, and body weight and several brain parameters at 30 days of age were studied in normal rats. At 30 days (‘adolescence’) cortex has already reached its final thickness and the rat exhibits long-term memory. Brain parameters included cerebral weight, DNA, protein and cholesterol contents and densities, as well as cortical and cerebral dimensions (cerebral sections). As expected, most of these parameters in 30-day-old animals were significantly correlated with each other. Unexpectedly, neonatal body weight was also significantly correlated with cholesterol content and density at 30 days, as well as with cortical and cerebral dimensions at 30 days. Thus, statistically, neonatal body weight already predetermines the extent of neuronal (cerebral) development at adolescence (30 days). This finding also makes it possible to make at birth statistical predictions about future brain development without having to sacrifice neonatal animals.
Light- and Electron-Microscopic Studies on the Gastric Parietal Cells in Perinatal Rats
Authors: Morikawa Y. , Matsuo S. , Eguchi Y. , Hashimoto Y.
Published: September 2009

Perinatal changes of the gastric parietal cells were studied under normal and various experimental conditions. Histologic examination revealed that the parietal cells appeared markedly increased in number from late fetal to early neonatal days. When premature newborn rats were delivered by cesarean section and were nursed by foster mothers for 1 or 2 days, the degree of increase of these cells reached nearly that in the normal neonates. On the other hand, in fetuses retained in utero 1 day beyond the normal gestation, these cells appeared not increased in number. When these postmature fetuses were delivered, the parietal cells turned to increase in number in a degree similar to that in the normal neonates. Milk given to the premature newborn rats caused 6 h later a marked increase in the number of the parietal cells. Milk given to fetuses in utero also caused an increase of these cells. The results suggest that the development of the parietal cells in perinatal rats is accelerated by the intake of milk and that the fetal parietal cells are ready to respond to milk given at least 1 day before birth.
Single Injection Clearance in the Neonate
Authors: Fawer C.L. , Torrado A. , Guignard J.P.
Published: September 2009

The single injection clearance of inulin was compared to the standard clearance in neonates aged 1–20 days. In the first 3 days of life, the single injection method overestimated glomerular filtration rate by approximately 30%. From the 2nd week of life, values obtained by the two techniques were not significantly different. We conclude that caution should be paid when interpreting results obtained by the single injection technique during the very first days of life.
Human Fetal Respiratory Movements: a Technique for Noninvasive Monitoring with the Use of a Tocodynamometer
Authors: Timor-Tritsch Ilan E. , Dierker, jr. LeRoy J. , Hertz Roger H. , Zador Ivan , Rosen Mortimer G.
Published: September 2009

A tocodynamometer applied to the maternal abdomen is used for monitoring human fetal respiratory movements (FRM). This provides a recording of fetal chest wall movements from which observations and measurements relating to fetal respiratory physiology may be made. The FRM must be differentiated from maternal vascular and respiratory movements, as well as fetal movements and cardiac pulsations. The technique lends itself to extended periods of observation, since it does not transmit energy to the fetus as in other techniques. The simplicity of the technique, combined with the use of monitoring devices already available in most hospitals, warrants further observation of this method of respiratory movement monitoring in the developing fetus.
Effect of Development on the Gangliosides of Rabbit Brain
Authors: Merat A. , Sajjadi S. , Dickerson J.W.T.
Published: September 2009

The effect of growth and development on the DNA and ganglioside-NANA of the rabbit forebrain, cerebellum and brainstem was studied. Animals were killed at 1 day of age and at intervals up to 180 days. The growth rate of each part of the brain fell during the first 30 days, but showed a spurt at about 40 days. The absolute amount of DNA reached its mature value by about 40 days. In the forebrain, the deposition of ganglioside-NANA rose sharply to a peak value at 50 days, falling to 120 days and rising again to 180 days, whereas in the cerebellum and brainstem the amount rose almost steadily to a mature value at 90 and 120 days, respectively. In the forebrain, the proportion of GDla and GM1 showed a reciprocal rise and fall, respectively, during the first 10 days after birth, subsequently falling and rising to near mature values by 50 days. GD1a was the major ganglioside in the mature forebrain, whereas GT1 and GD1b were the major gangliosides in the mature cerebellum and in the mature brainstem, respectively.
Neonatal Changes in the Plasma Levels of Cortisol, Cortisone and Aldosterone in the Calf
Authors: Cabello G.
Published: September 2009

Plasma levels of cortisol, cortisone and aldosterone were measured during the first 20 days of life in 10 healthy calves. Cortisolemia, high at birth, decreased from birth to day 15. Changes in plasma cortisone were similar to those of cortisol. The value of the cortisol/cortisone plasma ratio increased from birth to day 8 and remained steady until day 20. A positive correlation was found between plasma levels of cortisol and cortisone, during the 6- to 20-day period; no correlation was observed before that. These results raise the question of whether, as is assumed in the human, maternal cortisol would cross the placenta with conversion to cortisone in the bovine. Plasma aldosterone increased from day 1 to day 3, and decreased steadily until day 20 when its level was very low. Negative correlation found between the values of aldosterone and sodium led us to think that natremia regulation by this hormone could be functional in the neonatal calf.
Studies on the Effect of Acute Asphyxia on the Fetal Pig in utero
Authors: Randall G.C.B.
Published: September 2009

8 term fetal pigs (110–112 days gestation) and one 97-day fetus were asphyxiated in utero by occlusion of the umbilical cord. Mean times to last gasp and last heart beat were 5.1 and 22.4 for term and 5.4 and 30.4 min for the 97-day fetus. Cord occlusion was followed by profound bradycardia and an increase in blood pressure which was maintained until gasping ceased. Profound acidemia, hypercapnia and hyperlactacidemia developed in all animals and values following asphyxiation were comparable with those seen in stillborn piglets. Liver and cardiac glycogen levels were lower in asphyxiated fetuses than in littermates but muscle glycogen levels were similar in both groups.
Integrated Cardiovascular Responses to Combined Somatic and Visceral Afferent Stimulation in Newborn Piglets
Authors: Gootman N. , Gootman P.M. , Crane L.A. , Buckley B.J.
Published: September 2009

Mean aortic pressure, arterial flow and heart rate responses to interactions of afferent stimulation of the sciatic nerve (SNS) and carotid sinus stimulation by infusion (CSI) or inhibition by bilateral common carotid occlusion (BCCO) were studied in 25 newborn piglets under halothane-N2O anesthesia. Combined stimulation of the somatic and visceral afferents produced no heart rate changes. Combinations of pressor stimuli (BCCO and high frequency SNS) showed facilitation; femoral and renal resistances increased. However, combinations of depressor stimuli (CSI and low frequency SNS) showed occlusion. In combinations of pressor with depressor stimuli, the pressor pattern of responses dominated. Thus, dissimilar types of excitatory afferent inputs are capable of evoking facilitation in the neonatal cardiovascular regulatory system.
Balance of Net Base in the Rat
Authors: Wamberg S. , Engel K. , Kildeberg P.
Published: September 2009

The physiology of oral ammonium chloride loading was studied in four groups of male weanling rats weighing about 100 g and fed either standard ground Rostock® rat food (containing 317 mmol net base/kg) or ground barley (containing only 20 mmol net base/kg). One group of animals on the Rostock® diet received oral supplements of ammonium chloride (approximately 32 mmol·kg-1 day-1) sufficient to provide a net zero rate of oral net base intake. In this group, ongoing fecal net base excretion caused net acid to be absorbed at an average rate of 15 mmol kg-1 day-1. The mean rate of renal net acid excretion rose markedly (by 29.4 mmol·kg-1 day-1); and over an 8-day balance period the animals were able to maintain near-normal balances of net base. During a subsequent 8-day recovery the pattern of mineral turnover returned to normal. Even in the barley-fed rats, gastrointestinal net acid absorption was observed. These animals suffered a 61% reduction in the rate of body growth, but the overall rate of net base retention, per kilogram of mass gain, was close to the reference value. Finally, the combination of barley and ammonium chloride led to weight loss, positive net acid balances (8.5 mmol·kg-1, day-1, and a maximal rate of renal net acid excretion (50.8 mmol kg-1day-1).Some implications for the metabolism of organic acids are discussed.
‘Minor Hemoglobins’: an Alternative Approach for Evaluating Glucose Control in Pregnancy
Authors: Pollak Arnold , Widness John A. , Schwartz Robert
Published: September 2009

‘Minor hemoglobins’ (Hb AI) were measured in 178 women during pregnancy and immediately postpartum by a thiobarbituric acid spectrophotometric method. The patients were classified according to an oral glucose tolerance test (GTT) and an assessment of risk factors for diabetes in normal (n = 75), probably normal (n = 72) and chemical diabetics (n = 26). 5 pregnant insulin-dependent diabetics were also studied. Hb AI was unchanged during the second and third trimesters of pregnancy and immediately postpartum (< 6 days) in women with normal glucose tolerance. Moreover, no difference of Hb AI level was found when compared with a separate group of nonpregnant individuals (n = 15). Chemical diabetics had significantly higher mean third trimester and postpartum Hb AI than normals (p < 0.001). The highest Hb AI levels during pregnancy were found in the insulin-dependent diabetics, although these were lower compared to a separate group of nonpregnant insulin-dependent diabetics (n = 10; p < 0.05). During pregnancy, a significant correlation was found between Hb AI and the 2-hour value of the GTT (p < 0.001). A positive correlation was also found between third trimester maternal Hb AI and infant birth weight (p < 0.001). Hb AI may complement other parameters in evaluating maternal glucose tolerance during pregnancy.
Glucose and Galactose Infusions in Newborns of Diabetic and Healthy Mothers
Authors: Přibylová J. , Kozlová J.
Published: September 2009

The changes of insulin, blood sugars, lactate and free fatty acid levels were studied in 12 newborns of diabetic mothers and in 21 newborns of healthy mothers in the course of intravenous infusions of glucose and galactose at a dose of 0.5 g·kg––1·h––1. During glucose infusion a striking increase of insulin levels took place, which was higher in the infants of diabetic mothers. Galactose administration caused only a mild insulinemia increase in the 1st h of infusion. In the infants of healthy mothers blood glucose increased during the 1st h of infusion but decreased afterwards. In the infants of diabetic mothers the increase lasted for the whole time of infusion. The decrease of free fatty acid levels was present in the course of infusions of both sugars. The results show that galactose is quickly metabolized by the newborn and provokes minimal stimulation of the insular apparatus.
Relationships between Thyroid Function and Pathology of the Newborn Calf
Authors: Cabello G.
Published: September 2009

The plasma level of hormonal iodine at birth was measured in 28 calves which remained alive and in 13 animals, born in the same herd, which died within the first month of life. The mean value obtained in the first group (9.18 ± 0.88 μg/100 ml) was significantly higher (p < 0 0.025) than the value observed in the second group (5.63 ± 0.32 μg/100 ml). The neonatal changes in the plasma levels of hormonal iodine were observed from birth to 20 days of age in 32 healthy calves and in 36 calves which suffered from diarrhea but survived. It appears that the animals which remained healthy had significantly lower plasma levels of hormonal iodine at birth and at 48 h of age (respectively, 9.12 ± 1.14 and 6.03 ± 0.42 μg/100 ml) than those measured in the calves which became ill but survived (respectively, 16.18 ± 1.05 μg/100ml, p < 0.001, and 8.11 ± 0.43 μg/100ml, p < 0.005). No significant difference remained after this age. Measurements of the plasma levels of triiodothyronine and of the free-thyroxine index confirmed that the animals which were to become ill were in a hyperthyroid state at birth. We observed a negative correlation (p < 5%) between the plasma levels of hormonal iodine and of thyreostimulin at birth. These results suggest that thyroid dysfunction at birth could be associated with neonatal pathology in the calf, but that morbidity and mortality could not be associated with the same dysfunction. The possible relationships between thyroid function and the pathology of the newborn calf are discussed in the light of experimental results that we have obtained.
Absence of Transplacental Passage of ACTH in the Rat: Direct Experimental Proof
Authors: Dupouy Jean-Paul , Chatelain Akin , Allaume Patrick
Published: September 2009

In order to investigate whether ACTH can cross the placenta of the rat at term, porcine 125I-ACTH was injected into mothers or fetuses. ACTHwas then extracted from maternal and fetal plasma, using QUSO G-32, 2.5, 5, 10, 15 and 20 min after the injection of labelled ACTH. Plasma samples were also chromatographed on Sephadex G-50, fine, columns, 5 and 20 min after the administration of ACTH. When 125I-ACTH was injected into the mothers, the two methods used were unable to detect any radioactivity associated with intact ACTH in the fetal plasma. The same was observed in the maternal plasma when labelled hormone was administered to the fetuses. These observations provide direct experimental proof of the absence of transplacental passage in the rat of 125I-ACTH from the mother to the fetus as well as from the fetus to the mother.
Effect of Triiodothyronine Injection on Levels of Triiodothyronine and Thyroid-Stimulating Hormone in Sera and Milk of Lactating Rats and in Sera of Their Sucklings;Precocious Development of Jejunal α-Disaccharidases in the Sucklings
Authors: Koldovský Otakar , Krulich Ladislav , Tenore Alfred , Jumawan Jocelyn , Horowitz Carolyn , Lau Herbert
Published: September 2009

Administration of high doses of triiodothyronine (T3) for 4 days to lactating rats evokes an increase in T3 levels in their sera and milk, as well as in the sera of pups suckled by them. Thyroid-stimulating hormone levels in sera of mothers and sucklings are decreased. Suckling rats of T3-treated mothers exhibit a precocious increase in the activity of jejunal sucrase and maltase as well as in activity of several liver acid β-glycosidases.
In vivo Glycerol Metabolism in the Pregnant Rat
Authors: Chaves J.M. , Herrera E.
Published: September 2009

Pregnant rats at 12 and 21 days of gestation and their virgin controls were injected intravenously with U-14C-glycerol and decapitated 1, 3, or 10 min later. The conversion of labelled glycerol to 14C-glucose was augmented in the 21-day pregnant rats. The disappearance of the newly formed 14C-glucose from blood was faster in both 12- and 21-day pregnant rats than in their controls, being partially retained as liver 14C-glycogen. The greatest amount of radioactivity in all tissues appeared in the carcass hydrosoluble fraction. This amount was smaller in the pregnant rats. The reduced utilization of glycerol by extrahepatic tissues allowed the 21-day pregnant rats to dispose a greater amount of this substrate for gluconeogenesis.
Transepidermal Water Loss in vivo
Authors: Wilson Donald R. , Maibach Howard I.
Published: September 2009

In vivo, noninvasive, transepidermal water loss measurements were taken from 26- to 41-week gestational age infants with a Meeco® electrolytic water analyzer to yield information on the development of the function of the skin barrier. Infants 28 weeks or less have significantly greater transepidermal water loss than older gestational aged infants, thus indicating a less efficient barrier to water. Until it is known whether the decreased barrier function in premature infants also relates to percutaneous penetration, prudence is suggested in exposing such premature infants skin to chemicals.
Amino Acids in the Amniotic Fluid of Diabetic Mothers
Authors: Horská S. , Rážová M. , Vondráček J.
Published: September 2009

Subsequent to the spontaneous rupture of membranes in the 40th week of pregnancy, and in the course of labour inductions in cases of prolonged pregnancy (42nd week) and of diabetic mothers in the 40th week of pregnancy, the concentration of amino acids in the amniotic fluid was studied. In the group of diabetic mothers the concentrations of lysine, histidine, cysteic acid, taurine, serine, glutamic acid, glycine, alanine and phenylalanine are significantly higher. The arteriovenous difference found for some amino acids in the umbilical blood of physiological fetuses is absent in the fetuses of diabetic mothers.
Influence of the Compound NA872 on Cardiopulmonary Maturation in the Unanaesthetised Fetal Lamb
Authors: Maloney John E. , Brodecky Vojta
Published: September 2009

15 fetal lambs were instrumented on approximately day 100 (term 147 days) with small catheters in their jugular veins, carotid arteries and tracheas and fine electrodes in their diaphragms and on the lateral surfaces of their thoraces. Measurements were made intermittently of carotid arterial pressure, jugular venous pressure, amniotic fluid pressure, ECG and electrical activity in the diaphragm for 2-hour periods up to day 120. From day 120, two hourly recordings were made daily and samples of lung liquid taken until day 130. On this day, studies of lung mechanics were made on selected fetuses. From day 120, 8 animals were treated with the compound NA872 and 7 animals were given a control infusion of normal saline. In comparison to control animals the lecithin-sphingomyelin (L:S) ratio increased in the test fetuses from days 125–130; respiratory activity (diaphragmatic EMG) was suppressed in the test animals suggesting a more mature respiratory system; but resting lung volume on the test animals was smaller. Heart rate decreased as rapidly in the test animals while changes in systemic vascular pressures were similar. These results indicate that while the lungs are more ‘mature’ in that L:S ratio is increased, resting lung volumes are smaller, and respiratory activity is decreased. They raise the interesting questions of the influence of fetal respiratory activity on lung and thoracic cage development and the possible direct action of the drug NA872 on the respiratory pattern generator and the lung.