bluuebunny/crossref_metadata_2025 huggingface dataset:
The Actions of Vasoactive Drugs on Fetal and Maternal Plasma Renin Activity
Authors: Lumbers Eugenie R. , Lewes Jennifer Lee
Published: September 2009

The association between fetal arterial pressure and fetal plasma renin activity (PRA) was studied in 30 fetal lambs prepared acutely, but studied in utero. There was a negative correlation between resting fetal arterial pressure and resting fetal PRA (p < 0.05). Fetal hypotension caused by intravenous infusion of sodium nitroprusside was associated with increases in fetal PRA. Fetal hypertension caused by intravenous infusion of phenylephrine to the fetus was associated with a decrease in fetal PRA. Maternal hypotension caused by infusion of sodium nitroprusside to the mother, and maternal hypertension caused by maternal infusion of phenylephrine caused an increase in fetal blood pressure and a fall in fetal PRA. It is concluded that the liypertensive response of the fetus to these changes in maternal blood pressure was not initiated by the fetal renin-angiotensin system. Isoprenaline caused a rise in fetal PRA. In 11 of 28 infusions this increase in fetal PRA occurred even though diastolic pressure was increased. It is concluded that there is a β-adrenergic receptor in the fetal kidney which can release renin. The increase in fetal PRA with intravenous isoprenaline was blocked by propanolol. Infusions of adrenaline were not associated with increases in fetal PRA.
Effects of Neonatal Bulbectomy on Later Discrimination Learning in Mice
Authors: Cooper A.J. , Cowley J.J.
Published: September 2009

The olfactory bulbs of mice were lesioned at 24 h of age and their performance in learning a black-white discrimination task was compared with undernourished mice that grew from birth at the same rate as the bulbectomised animals. The mice were tested at 90 days of age and their behaviour in a Y-maze was compared with that of control operated and unoperated samples. The performance of the bulbectomised mice on the Y-maze was poorer than that of the other samples. The bulbectomised mice spent more time at the choicepoint and frequently failed to run the maze. The error rate reduction shown by the bulbectomised mice was similar to that of the controls and is accounted for in terms of a reduced frequency of entry and reversals into the maze arms. The results are discussed in relation to the size of the lesions and factors affecting the neurogenesis of the olfactory brain early in life.
The Effects of Theophylline on Renal Function in the Premature Newborn
Authors: Harkavy Kenneth L. , Scanlon John W. , Jose Pedro
Published: September 2009

The effects of aminophylline on renal function in 10 premature infants with idiopathic apnea are evaluated. The percent increases in creatinine clearance (128 ± 339%, mean ± SD) and sodium clearance (196 ± 304%, mean ± SD) are variable while the percent increase in fractional sodium excretion (69 ± 109%, mean ± SD) is significant. This effect is postulated to be at the proximal tubule and may be modified by the effects of postnatal age and infusion of albumin. Gestational age, birth weight, heart disease, water and sodium intake and ventilatory support did not appear to influence the results. Hyponatremia is a potential consequence of theophylline therapy for apnea.
Underlying Disorders Responsible for the Neonatal Deaths Associated with Low Apgar Scores
Authors: Naeye Richard L.
Published: September 2009

Data from a large study were used to determine the frequency of fatal disorders associated with low Apgar scores. 5-min scores had the best correlation with mortality rates. Death rates were more than ten times greater with abnormal than with normal 5-min scores. This difference was only 3-fold for 1-min values. Amniotic fluid infections were responsible for nearly half of the deaths in preterm and 24% of the deaths in term neonates with 5-min Apgar scores 0–6. The respective values for disorders that cause antenatal hypoxia were 25 and 24% and for major congenital anomalies, 7 and 28%.
Phototherapy and Neonatal Liver Function
Authors: Tan K.L. , Jacob E. , Chua K.S. , Woon K.Y.
Published: September 2009

Two groups of ‘healthy’ full-term infants with hyperbilirubinemia exposed to phototherapy for 72 h demonstrated no significant change in serum glutamic pyruvic transaminase (SGPT), isocitric dehydrogenase (SICD), alkaline phosphatase (SAP), heat stable alkaline phosphatase (HSAP), total protein and albumin values; these values were similar to those of a comparable group of control infants without hyperbilirubinemia. The bilirubin levels, however, decreased significantly during this period. In a separate group of full-term infants with hyperbilirubinemia, the bromsulphalein (BSP) test before and after 72 h of phototherapy also demonstrated no significant alteration; the results were comparable to a control group of infants. Phototherapy, even for a duration of 72 h apparently does not seem to affect liver function in infants with hyperbilirubinemia.
Hemopoietic Events in Human Embryonic Spleens at Early Gestational Stages
Authors: Djaldetti M.
Published: September 2009

The appearance of hemopoietic progenitor cells in human embryonic spleens at early gestational stages was observed with a transmission electron microscope. In spleens of 6- to 7-week-old embryos hemocytoblasts, proerythroblasts and megakaryocytic precursors were identified, located between the mesenchymal cells, suggesting that hemopoiesis in the embryonic spleen is an extravascular process. The relationship between hemopoietic and mesenchymal cells in the embryonic spleen is discussed.
Fetal Rat Adrenal Growth and Steroidogenesis in vitro after Maternal Dexamethasone Treatment
Authors: Klepac R. , Milković Karmeia
Published: September 2009

Two groups of female rats were treated with dexamethasone phosphate (DEX) for 24 h. One group received DEX in drinking water (10 μg/ml) on the 15th day of pregnancy (DEX15–16), and the second group on the 17th day of pregnancy (DEX17–18). The mothers and fetuses were sacrificed on the 20th and 22nd days of pregnancy. DEX reduced adrenal weights and concentration of corticosterone in plasma of the treated females and their fetuses. Fetal body weight was also reduced. However, the lightest adrenal glands were found in fetuses of the DEX17–18 mothers. Furthermore, the 19-day-old fetuses belonging to the DEX17–18 mothers had smallest amounts of corticosterone in plasma, and in plasma, and their adrenal glands produced the lowest amounts of radioactive corticosterone, 11-deoxycorticosterone and 18-hydroxy-ll-deoxycorticosterone from 4-14C progesterone after 1 h of incubation in vitro. In the 21-day-old fetuses belonging to both the groups of treated mothers, the production of steroids by the adrenal glands was similar and to the same extent reduced in comparison to the control fetuses.
Metabolic Response to Thyroxine in the Newborn Pig
Authors: Ślebodziński A.B.
Published: September 2009

The oxygen consumption rate (ml O2/kg/min), the pulse rate, respiratory frequency and body temperatures were measured after a single subcutaneous injection of thyroxine (80 μg/kg) or adrenaline (200 μg/kg) in unfasted pigs aged 1–11 days. Thyroxine produced a metabolic response after a latent period and potentiated the metabolic action of adrenaline. As reported in the literature, the existence of an immediate metabolic response to thyroxine was not evidenced. The obtained results support the view that in the newborn pig the physiological rise in metabolism which leads to metabolic stability might be caused by thyroxine, whose free fraction and highest level in the blood occurs shortly after birth. Potentiation of adrenaline action by thyroxine can contribute to this process.
The Metabolic Effects of Cold Exposure in the Newborn Rabbit
Authors: Molnár D. , Soltész G. , Mestyán J.
Published: September 2009

Blood glucose, lactate, plasma free fatty acid and plasma and tissue individual free amino acid levels were followed in newborn rabbits exposed for 10 h to an environmental temperature of 25 °C. Severe hypothermia developed with an increase of blood lactate and accumulation of total free amino acids in plasma and liver. Alanine, isoleucine, leucine, valine, phenylalanine, tyrosine, ornithine and taurine were elevated in the plasma; alanine and ornithine in the liver; leucine and isoleucine in the muscle.
Contents of Trace Elements in the Human Liver before Birth
Authors: Meinel B. , Bode J.C. , Koenig W. , Richter F.-W.
Published: September 2009

A multielement analysis was carried out in nine fetal livers (age: 23 weeks of gestation to term) in comparison to an adult control group (n = 37). 15 elements (phosphorus to lead) were analyzed by proton-induced X-ray emission (PIXE). Significant differences between the two groups, expressed as ratios (R) of fetal to adult liver values were observed for copper (R = 16), zinc (R = 2.0), iron (R = 1.5), calcium (R = 1.34), selenium (R = 1.22), manganese (R = 0.7), and molybdenum (R = 0.13). An interesting point seems to be the inverse relation of copper and molybdenum. The negative correlation of these two trace elements which is known from animal experiments has now been confirmed in the human liver.
Effects of Cyanogenic Agents on Reproduction and Neonatal Development in Rats
Authors: Olusi S.O. , Oke O.L. , Odusote Ayo
Published: September 2009

A diet consisting of 50% gari (a form of cassava meal) was found to cause no significant biochemical and haematological changes in adult female rats. Although this diet caused a significant increase in their serum thiocyanate levels, there was no corresponding significant increase in the weight of their thyroid glands. The offspring of these rats had significantly lower birth weights and brain weights and never attained the same adult weights as those of the controls. Adult female rats fed a diet consisting entirely of raw cassava had significantly reduced haematological and biochemical indices. This diet also caused an increased incidence of cannibalism and a significant reduction in the frequency of pregnancy, the average number of the litter and the birth weights among these rats. In addition there was an increased incidence of neonatal deaths among the offspring which also had poor development, reduced brain weights and an increased tendency towards biting their litter-mates. Adult female rats fed diets containing 5 and 10 g cyanide/100 g laboratory diet survived for more than 3 months but never became pregnant. They developed enlarged thyroid glands and tumours of the large intestine. The relevance of these findings to the areas of the world where cyanogenic glycosides form the staple diet is discussed.
Saccharin- or Quinine-Induced Changes in the Rat Pups following Prolonged Ingestion by the Dam
Authors: Lapointe G. , Nosal Gilliane
Published: September 2009

Effects presumably induced by a chronic free ingestion of saccharin (0.40 mg/ml) or of quinine (0.25 mg/ml) by female rats during the pregestative, gestative and lactating periods were investigated in the ensuing progeny. Preweaned pups were studied from birth up to weaning (21 days of age) by means of selected gross behavioral tests. The saccharin litters were mainly characterized by a slowering in the body growth evolution. The quinine pups demonstrate several physical anomalies: (1) congenital malformations in 5% of the animals; (2) a significantly reduced birth weight followed by a persistent growth retardation, and (3) a significant delay in the teeth eruption (1.6 and 2.6 days) and in the eye openings (1.6 days). In comparison to the untreated offspring, the saccharin pups showed minor effects whereas quinine-exposed rats were clearly impaired in several features of the postnatal physical development. Therefore, the addition of the sweetener to morphine solution may be convenient for the voluntary oral consumption of the narcotic. Conversely, quinine, used to habituate animals to drinking bitter solutions, has to be rejected in this narcotization procedure as being a harmful agent to the growing rat.
Brain TRH Levels during Development of the Rat, in Neonatal Hypothyroidism and after Caloric Deprivation
Authors: Oliver Charles , Giraud Pierre , Gillioz Pierre , Conte-Devolx Bernard , Usategui Ricardo
Published: September 2009

The effect of neonatal hypothyroidism and neonatal caloric deprivation on brain TRH levels and serum and pituitary TSH levels has been determined in rats on the following postnatal days: 1, 5, 10, 15, 25, 40 and 60. After neonatal hypothyroidism, there was a slight reduction in brain TRH content although TRH concentration in the brain increased. Serum TSH was elevated at birth, suggesting that the feedback of thyroid hormones on the pituitary gland acts in rat fetuses. After neonatal caloric deprivation, a decrease in brain TRH content was observed along with a decrease in circulating TSH levels, however, there was no change in brain TRH concentration.
Ontogeny of Sugar Transport in Fetal Rat Kidney
Authors: Lelièvre-Pégorier M. , Geloso J.P.
Published: September 2009

Concentration of α-methyl-D-glucopyranoside (α-MG) by kidney slices of rat fetuses increases during the studied period of gestation from day 18 until day 21 (last day of gestation). Glucoside transport is inhibited by phloridzin, D-glucose and D-galactose. Concentration dependence, over a substrate range from 0.01 to 0.2 mM, was studied on day 21: α-MG transport obeys a saturation kinetic with a low apparent Km (0.22 mM); D-glucose inhibition is of competitive nature (apparent Ki: 0.47 mM). Sodium dependence is demonstrated on day 21 of gestation: the phloridzine-sensitive transport, entirely inhibited in Na+-free medium, is enhanced when medium Na+ concentration increases from 0 to 143 mEq/l (Krebs-Ringer buffer concentration); further increase of Na+ concentration has no effect.
Carnitine Acetyltransferase in Developing Mammals
Authors: Seccombe D.W. , Hahn P.
Published: September 2009

Carnitine acetyltransferase (CAT) activity was determined in mitochondria and microsomes of liver and brown adipose tissue in fetal and postnatal rats, rabbits and guinea pigs. In rat liver and brown adipose tissue, mitochondrial CAT activity increased perinatally. Microsomal CAT activity also increased in brown adipose tissue. In liver, however, a rise was first noted after the 20th postnatal day. The ratio of mitochondrial to microsomal activity was higher in brown fat than liver throughout the period studied. Absolute values for both were always much higher in brown adipose tissue than in liver. Catalase activity (an enzyme localized in the peroxisomes) in rat liver increased after day 20 while in brown adipose tissue it attained a peak at 7 days after birth. At all times, hepatic activity exceeded activity in brown adipose tissue. The ratio on day 30 was 1 (brown adipose tissue) to 25 (liver). In both guinea pigs and rabbits, hepatic mitochondrial CAT activity was 10- to 20-fold higher than in the rat already prenatally. Microsomal activity, on the other hand, was approximately the same in all three species. It is concluded that probably only the mitochondrial CAT is directly related to fatty acid oxidation. The role of microsomal enzyme remains unclear.
Lung Compliance in Newborns with Patent Ductus Arteriosus before and after Surgical Ligation
Authors: Gerhardt Tilo , Bancalari Eduardo
Published: September 2009

Pressure volume curves of the lungs were determined in 10 premature infants (mean gestational age 31.4 weeks, mean birth weight 1,260 g) before and after surgical ligation of a patent ductus arteriosus (PDA). 7 infants who had low compliance initially showed a significant improvement in lung compliance after surgery, while 3 infants whose compliance was close to normal before surgery had a decrease after ligation. In conclusion, a PDA with left to right shunt is frequently associated with a decrease in lung compliance that improves after ligation. Measurement of lung compliance in infants with PDA can be helpful in predicting the degree of improvement in lung function that may result from the closure of the ductus.
Hemodynamic Responses of the Pelvic Vascular Bed to Vasoactive Stimuli in Pregnant Sheep
Authors: Tabsh Khalil , Nuwayhid B. , Erkkola R. , Zugaib M. , Lieb S. , Ushioda E. , Brinkman III C.R. , Assali N.S.
Published: September 2009

The responses of the common internal iliac artery and middle uterine artery of the pregnant horn to continuous infusions of graded doses of norepinephrine, epinephrine, dopamine, isoxsuprine, angiotensin and nitroprusside were investigated in chronically instrumented pregnant ewes. Norepinephrine progressively decreased the blood flow and increased the resistance in both vessels but the changes were more marked in the middle uterine artery. Isoxsuprine and epinephrine had an insignificant effect on the common internal iliac artery blood flow, but decreased that of the middle uterine artery. Nitroprusside decreased the flow in both vessels proportionately. Angiotensin in doses less than 0.16 µg/kg/min increased the flow in both arteries to the same extent, but higher doses decreased both flows. It is concluded that in the chronically instrumented pregnant ewe, the responses of contiguous vascular beds to different vasoactive agents may differ depending on the nature of the stimulus.
Noradrenergic Control of Blood Vessels in the Premature Lamb Fetus
Authors: Zink Joe , Van Petten Garry R.
Published: September 2009

Experiments were conducted with fetal lambs of 113–120 days gestation (0.8 term) to assess the integrity of adrenergic neurotransmission at the level of the blood vessels. Regional blood flow and the distribution of blood from the inferior vena cava were compared when the arterial pressure was increased either by an infusion of exogenous noradrenaline or when tyramine was used to evoke a local release of the neurotransmitter. Most vascular beds perfused via the descending aorta were constricted to a similar extent by both drugs although the renal circulation did not respond to tyramine. Noradrenaline increased the distribution of blood from the inferior vena cava to the fetal lungs and both drugs increased placental blood flow. These data indicate that mechanisms for effective adrenergic control of vascular resistance are developed in many organs of the premature lamb fetus by 0.8 of term.
Effect of Acute Nonsurgical Stress on Fetal and Maternal Plasma Glucose, Glucagon and Insulin Concentration in Sheep
Authors: Schreiner R.L.. , Lemons J.A. , Gresham E.L. , Nolen P.A. , Bohnke R.A. , Reyman D.S.
Published: September 2009

The purpose of this study was to investigate the effect of nonsurgical stress on plasma glucose, insulin and glucagon in the ewe and fetus. Plasma glucose, insulin and glucagon were measured before and after a 2 min period of verbal and physical startling of much greater magnitude than that to which the ewe is exposed during routine blood drawing. Studies were completed on 5 fed ewes, 5 fasted ewes and on 4 fetuses of fasted ewes. There were no significant differences after startling compared to the control values. Thus, there appears no need to allow the ewe a prolonged period (more than 1–2 weeks) to become accustomed to handling by humans before chronic metabolic studies involving serum glucose, insulin and glucagon are undertaken.
Development of Proteolytic Activity in Rabbit Fetal Intestine
Authors: Morin Pierre-R. , Potier Michel
Published: September 2009

The development of proteolytic activity was determined in rabbit fetal intestine using 125I-hemoglobin as substrate. This assay method allowed increased sensitivity and complete linearity with incubation time and amount of homogenate protein. The effect of pH on substrate hydrolysis showed two main peaks of activity around pH 5 and 8. The apparent Km of proteolytic activity for the 125I-hemoglobin substrate was 0.57mg/ml at pH 8. Proteolytic activity increases about 10-fold in fetal rabbit intestine between 21 and 31 days of gestation.
Hepatic Cellular Development in the Rabbit
Authors: Milner R.D.G. , Pownall L.
Published: September 2009

Cellular development of rabbit liver from late fetal life to adulthood was analysed by quantitative histology and chemical techniques. Hepatocytes and non-hepatocytes were described in number and size. Two thirds of the cells in fetal liver are non-hepatocytes but the volume fraction occupied by them is only 18 %. Both number and volume fraction fall with advancing development. Hepatocyte cytoplasm doubles in late fetal life, falls in the 1st postnatal week and then increases to a maximum size in the adult. Perinatal changes in hepatocyte size are related to the accumulation and discharge of glycogen and lipid but also include changes in the protein concentration of the cell.
Control of Urea Synthesis in Fetal Rat Liver Slices
Authors: Husson A. , Fairand A. , Vaillant R.
Published: September 2009

Urea synthesis in fetal rats was studied using a liver slice system with ammonium chloride as nitrogen source. In term fetuses, the rate of urea formation increases with ammonium chloride concentration up to 100 μM and is enhanced by the addition of ornithine. The developmental pattern for urea synthesis is very similar to that found in the enzyme activity studies: urea production increases slightly during fetal life and then rises rapidly at birth. It is found that fetal liver has an absolute requirement for glucocorticosteroids to develop a normal urea synthesis. The accordance with argininosuccinate synthetase activity measured in liver homogenate is discussed.
Serum Cholic Acid and Chenodeoxycholic Acid Concentrations in Neonatal Hyperbilirubinemia
Authors: Finni K. , Similä S. , Koivisto M. , Heikura S. , Mäentausta O. , Jänne O.
Published: September 2009

Primary bile acid concentrations were measured in serum of 332 newborns with neonatal hyperbilirubinemia (serum total bilirubin level > 200 μmol/l) and compared with those of 95 nonhyperbilirubinemic neonates (serum total bilirubin level < 200 μmol/l). The serum concentrations (μmol/l; mean ± SEM) for cholic acid (8.78 ± 0.44) and chenodeoxycholic acid (10.5 ± 0.68) were significantly higher (p < 0.001) in the hyperbilirubinemic group than in the controls (7.16 ± 0.48 and 6.67 ± 0.48, respectively). 80 (24%) of the hyperbilirubinemic newborns had true cholestasis (serum levels of cholic and/or chenodeoxycholic acid higher than mean +2 SD in the reference group). The ratio of cholic to chenodeoxycholic acid was significantly higher (p < 0.05) in the cholestatic group than in the hyperbilirubinemic newborns without cholestasis. There was no significant difference in the serum concentrations of alkaline phosphatase or lactate dehydrogenase between the cholestatic and noncholestatic groups. In the hyperbilirubinemic newborns, the primary bile acids were indiscriminately raised. Only 8 infants from the 332 newborns had jaundice at the age of 1 month. Of these 8 infants only 2 had neonatal cholestatic hyperbilirubinemia. It thus appears that measurement of serum primary bile acid concentrations has only limited diagnostic value in assessing the severity or prognosis of neonatal hyperbilirubinemia.
Increased Erythropoiesis in Embryonic Spleen of Polycythemic Mice
Authors: Notti Ida , Bessler Hanna , Djaldetti Meir
Published: September 2009

The hemopoietic events in the embryonic mouse spleen were investigated in fetuses of polycythemic mothers. 12th and 13th day embryonic spleens showed a marked increase in the number of erythroid precursors at an advanced maturation stage, as compared to controls. In addition, an increased erythropoietic activity, measured by 59Fe incorporation into red blood cells of posthypoxic polycythemic mice, was found in the plasma of 12th and 13th day pregnant polycythemic mice, compared with controls, i.e. plasma of nonpregnant nonpolycythemic mice, of nonpregnant polycythemic mice, and of 12th and 13th day pregnant nonpolycythemic mice. Since polycythemic mice are presumed to have low erythropoietin level, the stimulation of erythropoiesis in the embryonic spleens of polycythemic mothers suggests that fetal erythropoiesis is independent of the maternal one. Moreover, the present results indicate that fetuses of polycythemic mothers not only produce their own erythropoietin, but are also able to increase markedly the maternal erythropoietin as a consequence of hypoxemic conditions.
Ultrastructure of Developing Human Muscle
Authors: Minguetti Guilberto , Mair W.G.P.
Published: September 2009

The ultrastructure of developing human muscle and the structures intimately related to it were studied, the material being obtained from fetuses ranging from 9 weeks to 9 months of development. Muscle of a male fetus from a known carrier of muscular dystrophy was also investigated. The features of myoblasts, myotubes and muscle fibres and their interrelationships are described. While most of the myotubes in the fetus obtained from the known muscular dystrophy carrier are like those of the other fetuses, its muscle also contains myotubes which show obvious structural changes and such changes do not occur in the myotubes of any of the other fetuses.
Parathyrin and Calcium Homeostasis in the Fetus
Authors: Wadsworth J.C. , Kronfeld D.S. , Ramberg C.F., Jr.
Published: September 2009

The response of plasma parathyrin (PT) in cattle fetuses to changes in plasma calcium was investigated in utero. Resting plasma calcium levels for 4 fetuses averaged 3.1 mg/dl higher than for their mothers. Fetal PT levels (0.67 ng/ml) were half those of the mother (1.40 ng/ml). Hypocalcemia induced by EDTA infusion evoked a rise in plasma PT in 2 of 3 fetuses. The relationship between plasma PT and calcium levels in these fetuses was curvilinear, PT rising from about 0.7 ng/ml at 13mg calcium/dl to a plateau of about 1.6 ng/ml below 10 mg calcium/dl. This contrasted with one of the mothers in which PT rose above 3 ng/ml when plasma calcium fell from 9 to 7 mg/dl. During infusion of EDTA to mother or fetus there were no changes in plasma calcium or PT levels in the respective fetus or mother.
Supply and Release of Storage Neutrophils
Authors: Erdman Steven H. , Christensen Robert D. , Bradley Peter P. , Rothstein Gerald
Published: September 2009

Depletion of the mature neutrophil reserve during bacterial sepsis is rare in adults but common in neonates; when it occurs, a fatal outcome is likely. Neutrophil reserve depletion was investigated in groups of premature, 1-day-old and 1-, 2-, and 4-week-old rats by measuring: (1) the size of the neutrophil storage pool, and (2) the proportion of this pool which was released from the storage compartment when a weight-standardized release stimulus was applied. It was found that the premature rat has a small neutrophil storage pool containing 1.28 ± 0.07 × 106 cells/g body weight (x ± SE). This pool size increases to contain 4.35 ± 0.23 × 106 cells/g in the 4-week-olds (p < 0.001). With a standard neutrophil storage pool release stimulus, the premature rats depleted 68 ± 4% of their neutrophil stores, vs. a depletion of only 13 ± 6% of the stores in the 4-week-olds (p < 0.001). The small neutrophil reserve and the exaggerated release of stored neutrophils in neonatal animals are factors which predispose neonates to neutrophil reserve exhaustion during bacterial sepsis.
New Evidence that the Intra-Uterine Growth-Retarded Piglet Is a Member of a Discrete Subpopulation
Authors: Royston J.P. , Flecknell P.A. , Wootton R.
Published: September 2009

The statistical distribution of birth weights in 54 litters of piglets was examined in an attempt to identify intra-uterine growth-retarded animals. Although birthweight distribution was normal in some litters, in others there appeared to be a discrete subpopulation of 1 or more growth-retarded animals. Inspection of published data from the rat and mouse suggests that a similar phenomenon occurs in other polytocous species. These findings imply that growth-retarded neonates of these and possibly other species should not be regarded as the tail-end of a normal distribution, but that they are the result of some distinct process occurring during gestation.
Uptake and Turnover Rate of Norepinephrine in Interscapular Brown Adipose Tissue of the Young Rat
Authors: Gripois D. , Valens M.
Published: September 2009

Norepinephrine uptake and turnover rate were measured in the interscapular brown adipose tissue of normal and hypothyroid young rats. At the age of 15 days, hypothyroidism lowers the uptake of norepinephrine. This fact could partially explain why the norepinephrine content of the tissue has previously been found reduced in these animals when compared to controls. In the same animals, the turnover rate of norepinephrine is reduced by 80%. This indicates a decrease of the sympathetic tonus in the tissue.
Lipoprotein and Lipid Profiles in the Blood Serum of the Fetal, Neonatal and Adult Pig
Authors: Johansson Magnus B.N. , Karlsson Börje W.
Published: September 2009

As revealed by agarose gel electrophoresis and immunoassay, followed by staining with Sudan black, lipoproteins occur in the α-, pre-β- and β-regions of the serum of fetal, newborn, neonatal, juvenile and adult pigs. These lipoproteins undergo characteristic quantitative changes during development. After the onset of colostrum ingestion, a lipid-stainable zone appeared in the γ-region of piglet’s serum and sow colostrum/milk. The levels of total serum lipids, cholesterol, high and low density lipoproteins were low at birth in comparison to those of the adult pig, but increased to higher levels after the onset of colostrum and milk ingestion. After 3–8 weeks, the total lipids, cholesterol and low density lipoprotein values had decreased to adult level but the high density lipoprotein values remained high in comparison to the adult pig. It is discussed that the changes found in lipoprotein and lipid patterns in serum of the developing pig reflect changes in cellular metabolism and nutritional needs of the organism. It is suggested that the perinatal pig might be a useful model for studying the development of atherogenic diseases in man.
Trans Fatty Acids: Transport and Positional Specificity in Rat Placental Lecithin
Authors: Moore C.E. , Dhopeshwarkar G.A.
Published: September 2009

Differences in positional incorporation of trans and cis isomers of octadecenoic and octadecadienoic acids in placental lecithin of rats was demonstrated. A 14C-labeled albumin complex of elaidic, oleic, linoelaidic, or linoleic acid was injected into the jugular vein of pregnant rats. 6 h later 45–64% of the total radioactivity in placental lipids was found in phospholipids (PL), with a major portion of the label incorporated into choline phosphoglycerides (CPC). Following hydrolysis of placental CPC by phospholipase A2, distribution of radioactivity within isolated fatty acids and lysolecithin suggested preferential incorporation of t, t-,18:2 at position 2 and a nearly equal distribution of t-18:1 at positions 1 and 2.
Onset of Thermogenesis in Response to Cold in Newborn Mice
Authors: Vinter J. , Hull D. , Elphick M.C.
Published: September 2009

The onset of thermogenesis in response to cold exposure in individual mice was studied using a sensitive close circuit system for measuring their rate of oxygen consumption. On the day of birth, exposure to a cool environment did not stimulate an increase in oxygen consumption, but 48 h later the majority of mice respond by doubling their metabolic rate in response to a fall from 36 to 31 °C in ambient temperature. When 5 mice huddled together an ambient temperature drop from 36 to 23 °C was required to provoke the same response. Brown adipose tissue is present at birth but the cells are relatively small and contain little fat. By the second day they are three times larger and contain far more fat. The onset of thermogenesis appears to await the development of brown adipose tissue.
Inhibitory Effects of Bilirubin and Photobilirubin on Neonatal and Adult T Lymphocytes and Granulocytes
Authors: Rubaltelli Firmino F. , Granati Bruno , Fortunato Antonio , Piovesan Annalisa , Casara GianLuca , Colleselli Paolo , Semenzato Gianpietro
Published: September 2009

The lymphoproliferative response to phytohemagglutinin of lymphocytes and spontaneous motility, chemotaxis and phagocytic activity of granulocytes were studied in the newborn and adult blood in the presence of bilirubin and photobilirubin. All of these activities were inhibited to the same extent by these substances. In addition, a significant difference between newborn and adult values was found. In conclusion, the authors suggest that phototherapy does not decrease bilirubin cellular toxicity.
Quantitative Bacteriological Analysis of Amniotic Fluid
Authors: Courcol R.J. , Roussel-Delvallez M. , Puech F. , Delecour M. , Martin G.R.
Published: September 2009

Quantitative bacteriological analysis of amniotic fluid (AF) was performed on 60 fluid samples collected by catheter from 50 selected labor patients regarded as liable to infection. AF cultures were positive in 52 cases. The bacterial colony counts ranged from less than 102 colony-forming units (CFU) per milliliter to 109 CFU/ml. Pathogenic bacteria in neonates such as group B Streptococcus, Escherichia coli, and Listeria monocytogenes were encountered with numerations equal to or greater than 107 CFU/ml in groups with clinical findings. An excellent correlation was noted between bacterial counts in AF and clinical data (p < 0.00006). The results confirm that the quantitative bacteria analysis of the AF is a useful tool for evaluation of an infection risk for neonates.
Influence of Corticosteroids on Glycogen Content and Steroid 11-Reductase Activity in Lung and Liver of the Fetal and Newborn Rat
Authors: Smith Barry T. , Tanswell Keith , Minshall D. , Bogues W.N. , Vreeken E.
Published: September 2009

Lung and liver glycogen and corticosteroid 11-reductase activity were studied in fetal and neonatal rats. Glycogen content peaked in the lung on day 20 of gestation, while hepatic glycogen content was generally lower and peaked later. Both pre- and postnatally, betamethasone administration resulted in lowered pulmonary and elevated hepatic glycogen. In both lung and liver, corticosteroid 11-reductase activity showed an inverse developmental pattern to glycogen content. Betamethasone elevated pulmonary corticosteroid 11-reductase activity and lowered hepatic activity. In lung and liver, glycogen content and corticosteroid 11-reductase activity are tightly linked during development and following glucocorticoid therapy.
Mathematical Description of the Temporal Changes in Serum Bilirubin Concentration during Phototherapy in Newborn Infants
Authors: Wiese G. , Ballowitz L.
Published: September 2009

Deriving from experiments in Gunn rats, an equation is developed which allows one to calculate and predict the photoeffect in human babies, when phototherapy begins between days 3 and 5. The serum bilirubin level at the start, the illuminated body surface and the effective irradiance applied are taken into consideration.
Studies on Rat Hepatic Mitochondrial Hydroxymethylglutaryl-CoA Synthase during the Perinatal Period
Authors: Caswell Alison M. , Bailey Ernest
Published: September 2009

Rat hepatic mitochondrial hydroxymethylglutaryl-CoA (HMG-CoA) synthase activity increases throughout the perinatal period, indicating that the factors necessary for the induction of the enzyme are present in utero. Reciprocal changes occur in 3-ketoacid transferase activity during late fetal life, suggesting that ketone body formation and utilization may be subject to coordinate regulation. Cytosolic HMG-CoA synthase activity is low during fetal life and rises rapidly after birth. The activities of both cytosolic and mitochondrial enzymes in fetal liver are dependent upon maternal diet and different dietary effects are observed at different fetal ages.
Serum Retinol and Retinol-Binding Protein in Mothers and Infants at Delivery
Authors: Jansson Lennart , Nilsson Bertil
Published: September 2009

The relations at birth between infant and maternal serum retinol, retinol-binding protein (RBP) and retinol/RBP molar ratio were investigated in 25 healthy term infants and their mothers. The mean serum levels of retinol and RBP were significantly higher in the mothers, but the mean molar ratio of retinol/RBP (RBP saturation) was significantly higher in the infants. Both the infant serum RBP and the infant RBP saturation were ositively correlated to the respective serum levels in the mothers.
Effect of Lithium on Reproduction and Postnatal Growth of Mice
Authors: Mroczka Deborah L. , Hoff Kenneth M. , Goodrich Cecilie A. , Baker Peter C.
Published: September 2009

Mating pairs of mice were maintained continuously on drinking water containing 50 mEq/l LiCl and its effects on reproduction and postnatal development were monitored. In mating pairs put on lithium at 6–8 weeks of age, the lithium does not appear to reduce litter size at birth but it does increase postnatal mortality and the length of time between litters, and reduces the total number of litters a mating pair may have. In mating pairs put on lithium at 3 weeks of age, it severely delays postnatal growth and development of all pups in the litter. With the exception of the liver, this delayed growth and development does not appear to affect internal organs as severely as somatic body parts. This delayed growth may be the result of some effect lithium may have on certain hormones such as prolactin, thyroxine and growth hormone.
Responses of the Newborn Infant to Overheating
Authors: Harpin V.A. , Chellappah G. , Rutter N.
Published: September 2009

The responses of newborn babies to overheating were investigated by exposing them to progressively higher incubator air temperatures until either sweating occurred or the rectal temperature reached 37.9 °C. 112 studies were performed on 83 healthy term and preterm infants. Activity, posture, heart rate, respiratory rate, skin colour and abdominal skin and hand temperature were monitored. Most babies regardless of gestational age became less active, and they frequently fell asleep at the warmest setting. The majority of infants altered their posture from predominantly flexion to extension. There were no significant changes in heart rate or respiratory rate. The skin of almost all the babies became redder, and the difference between central and peripheral skin temperatures decreased with warming. The pattern of these changes varied with maturity suggesting the development of vasomotor control. It is a surprising finding that even the most immature babies appear to make appropriate responses to heat stress. These responses may aid in the recognition of a baby who is too warm.
Effect of Liver Hypothermic Preservation: Exploration and Protection
Authors: Ben Ali R. , Klouz A. , Elkadri N. , Kourda N. , Gaies E. , Ben Saîd D. , Lakhal M. , Belkahia C.
Published: September 2009

Background/Aims: The principal aim of conservation is to maintain the viability of grafts. This requires the addition of a cellular protector allowing better conservation of the graft. The aim of this work is to evaluate the effect of trimetazidine (TMZ) addition to Wistar rat livers conserved in Krebs-Henseleit solution, compared to the livers preserved only in Krebs-Henseleit solution (24 h at 4°C). Methods: 40 Wistar female rats divided into 5 groups were used: the first group consists of nonpreserved livers, the second consists of livers preserved only in the Krebs-Henseleit solution, and the other 3 groups consist of livers preserved in Krebs solution with different concentrations of TMZ added (16.5, 49.5 and 165 μg/ml). Results: The obtained results show an improvement in the state of the liver in the presence of a high concentration of TMZ, which approaches normal physiological conditions. We note a clear diminution of transaminase activities, as well as an amelioration in metabolic capacities of the liver if the mitochondrial esterase pathway is supported in Wistar rats by a reduction of histological injuries. Conclusion: A TMZ concentration of 165 μg/ml clearly restored the metabolic capacities of the liver. Indeed, TMZ limited the appearance of necrotic areas and almost suppressed apoptotic cells.
Lipoproteins and Lipids in Fetal, Neonatal and Adult Rat Serum
Authors: Johansson Magnus B.N.
Published: September 2009

Levels of the serum lipoproteins (HDL, LDL and VLDL) and lipids in the fetal, neonatal and pregnant rat were measured using electrophoretic, immunological and biochemical methods. The results were compared to those of the adult rat. In the fetal rat at the end of gestation, the lipoprotein pattern was dominated by LDL (β-lipoprotein). Fetal HDL (α-lipoprotein) occurred at a low concentration and showed a lower proportion of cholesterol and a higher proportion of triglycerides than did HDL in the adult rat serum. VLDL (pre-β-lipoprotein) was present only at very low concentrations. The lipoprotein pattern of suckling neonatal rats showed rapidly increasing levels of VLDL and LDL, and high serum lipid values during the first 2 weeks after birth. The lipoprotein pattern of the adult rat, with the HDL fraction dominating, was completely developed by about 4 weeks after birth. In rats during late pregnancy, very high serum values were found for VLDL and LDL. High levels of triglycerides associated with these fractions were also seen. The serum lipoprotein development of the fetal and neonatal rat is different from that reported for the pig and man. This focuses the interest on the differences in lipid and lipoprotein metabolism between species during ontogenic development.
Triiodothyronine Nuclear Receptors in Liver, Brain and Lung of Neonatal Rats
Authors: Bellabarba Diego , Fortier Suzanne , Bélisle Serge , Lehoux Jean-Guy
Published: September 2009

In this study we have examined the effect of neonatal hypothyroidism and triiodothyronine (T3) replacement therapy on the maximal binding capacity (MBC) and the affinity of T3 receptors prepared from liver, brain and lungs. Rats were radiothyroidectomized at birth and administered T3 or its placebo starting at 8 days of age. The thyroid state in normal, hypothyroid and hypothyroid T3-treated rats was assessed by serum determination of thyroxine, T3 and by the measurement of the hepatic α-glycerophosphate dehydrogenase. The animals were sacrificed at 8, 16 or 24 days of age and the T3 binding was estimated in isolated nuclei and in salt nuclear extracts. The MBC of the T3 receptors was higher in the hypothyroid rats at all ages when it was determined in isolated nuclei, but not when was measured in nuclear extracts. At 8 days, the MBC had risen twofold or more in the receptors from brain (1.0 ± 0.37 vs. 0.4 ± 0.1 ng T3/mg DNA in controls) and from lungs (0.6 ± 0.25 vs. 0.3 ± 0.15 ng T3/mg DNA in controls), but was only slightly elevated in the hepatic receptor (0.62 ± 0.08 vs. 0.48 ± 0.15 ng T3/mg DNA in controls). At 16–24 days, the highest value of MBC was observed in the hepatic receptor (0.83 ± 0.04 vs. 0.41 ± 0.1 ng T3/mg DNA in controls) followed by the brain receptor (0.65 ± 0.03 vs. 0.35 ± 0.02 ng T3/mg DNA in controls), and that of lung (0.39 ± 0.07 vs. 0.20 ± 0.03 ng T3/mg DNA in controls). T3 replacement therapy caused a marked diminution of the MBC of the hepatic receptor (0.54 ± 0.07 ng T3/mg DNA), but had little effect on brain and lungs. No changes in affinity were observed throughout the experiments. It has been concluded that the increase of MBC in hypothyroidism probably represents a protective mechanism which provides an adequate amount of T3 to the cellular structure responsible for initiating the hormone action. T3 replacement therapy restores the MBC to normal in receptors from tissues (liver) that bind especially T3 from plasma, but not in tissues which need locally generated hormone to occupy their receptors (brain and lungs).
Effect of Fetal Decapitation on the Composition and Metabolic Characteristics of Pig Skeletal Muscle
Authors: MacLarty J.L. , Campion D.R. , Hausman G.J. , Reagan J.O. , Meredith F.I.
Published: September 2009

The effect of fetal decapitation on the compositional and metabolic characteristics of the biceps femoris muscle of the pig was studied. Fetuses were decapitated at 45 days of gestation and sampled at 110 days of gestation. Muscle wet weight was greater and total dry matter was lower in decapitated (D) than in control (C) fetuses. Total muscle triglyceride content was not influenced by decapitation, but the triglyceride concentration was lower in D when compared to C fetuses. Muscle cell number (total muscle DNA) was not influenced by decapitation, but protein/DNA was greater in the muscle of D than C fetuses. Aerobic metabolism, as measured by oxidation of pyruvate, isoleucine, and palmitate to CO2, was not influenced by decapitation. The rate of palmitate esterified and the ratio of palmitate oxidized/esterified was normal in decapitated fetuses. While the tricarboxylic acid cycle appeared to function normally, pentose shunt activity was higher in the decapitated fetal muscle than in control muscle. Although the rate of decarboxylation of leucine was lower in the muscle of D than in C fetuses, the net rate of leucine transaminated was similar between C and D fetuses.
Intestinal Transmission of Macromolecules (BSA and FITC-Labelled Dextrans) in the Neonatal Pig
Authors: Weström B.R. , Svendsen J. , Ohlsson B.G. , Tagesson C. , Karlsson B.W.
Published: September 2009

The intestinal transmission of two macromolecular markers, of similar molecular weight but different susceptibility to proteolytic digestion, was investigated in the neonatal pig. Piglets of varying age (0 h-7 days old) were given a mixture of bovine serum albumin (BSA) and fluorescein-sothiocyanate labelled dextran 70,000 (FITC-D 70) by stomach tube, and the serum concentrations were determined 2 h after feeding. A high correlation between the patterns of transmission were obtained for the two marker substances (r = 0.91 n = 39). Furthermore, a rapid decrease in the transmission of the markers was observed during the first day of life in suckled piglets, and intestinal macromolecular closure was well developed in the piglets after 18–36 h of life. These findings indicate that Ê»closure’is unrelated to changes in intestinal proteolytic activity. After closure, only small amounts of the markers were transmitted to the serum. During the first day of life, great individual differences in the transmission were found between piglets. As shown by feeding different-sized FITC-D (MW = 3,000–70,000 dalton) and unconjugated FITC (MW = 389 dalton), molecules having a molecular weight greater than 3,000 daltons were excluded upon macromolecular closure. On the other hand, smaller molecules like FITC were transmitted across the intestinal barriers independent of closure.
Duodenal Uptake of Lead by Suckling and Weanling Rats
Authors: Henning Susan J. , Leeper Lucy L.
Published: September 2009

The aim of the current study was to determine the site of absorption of Pb by suckling rats. When 203PbCl2 (carrier-free) plus Pb-acetate (50 μg/g BW) was intragastrically administered to rat pups aged 10 and 14 days, mucosal uptake of Pb, measured 2h after intubation, was manyfold greater in the duodenum than in other regions of the small intestine. By 24 days of age, this duodenal uptake was no longer apparent. In suckling pups the duodenal content of Pb became undetectable by 24 h postintubation; in contrast, ileal uptake was minimal at 2 h but increased progressively through 24 h. The ileal uptake component was also age-dependent, having disappeared by 24 days of age. These findings suggest that it is the duodenum where Pb absorption occurs, whereas ileal uptake represents intestinal retention. To assess the role of the milk diet in the elevated Pb absorption by the duodenum of suckling animals, the effect of fasting following intubation was determined. The duodenal uptake of Pb was substantially higher in fasted pups than in suckled littermates. Correspondingly, blood Pb levels were more than 4-fold higher in fasted pups than in suckled pups. We conclude that the enhanced absorption of Pb in the suckling rat is due to duodenal absorption and that this absorptive process is even further enhanced in the absence of milk.