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Biomedical subjects

F Bagnoli

Publications and source records attributed to F Bagnoli.

At least 55 records · Page 3Linked to original sources

[Serum levels of parathormone, calcium, magnesium and phosphorus in the perinatal period].

Two groups of newborns on different diets were studied: group A was given artificial milk, while group B was breast fed. Blood samples from the cord artery and vein were taken at birth and further blood samples after 1, 6, 12, 24, 48, 72, 96 and 168 hours. No baby underwent more than three blood samples. Calcium (Ca), magnesium (Mg), phosphorus (P) and parathormone (PTH) were measured in all samples. There was a rapid increase in PTH levels in all subjects in the first hours after birth. At 48th the babies in group A had significantly higher serum levels of P than the group B subjects, and their serum Ca and Mg levels were significantly lower. At 72th PTH serum levels were significantly higher in group A, while Ca and Mg levels were significantly higher in group B. In conclusion, the subjects demonstrated a normal secretion of PTH at birth, and the type of diet notably influenced the homeostasis of calcium in the perinatal period.

Breast Feeding↗

[Kinetics of erythrocyte populations in newborn infants with hyperbilirubinemia].

Determinations of erythrocyte glucose-6-phosphate dehydrogenase, pyruvate kinase and glucose-phosphate isomerase activities have been carried out in jaundiced and non-jaundiced newborn infants at birth and after 5 days of life. Only hyperbilirubinemias of unknown etiology have been considered. Previous investigations have demonstrated that erythrocyte age dependent enzyme activities decrease in the healthy newborn during the first week of life. Following the results of the present paper, jaundiced newborns do not show such a decrease, since a statistically significant difference between paired data of glucose-6-phosphate dehydrogenase and pyruvate kinase in jaundiced and non-jaundiced newborns have been found. It is likely that the lack of decrease of enzyme activities in the jaundiced infants depend upon the loss of oldest red cells with low glucose-6-phosphate dehydrogenase and pyruvate kinase. Our observation suggests the occurrence of a slight hemolysis in newborn infants with hyperbilirubinemia of unknown etiology.

Erythrocyte Aging↗

[Methemoglobinemia and acidosis during the first week of life].

Recently attention has been called on the possible role of acidosis in the increased methemoglobin formation in the erythrocyte of newborn infant. In the present paper the relations between acidosis and methemoglobin content in the red cells of newborns has been investigated. No significant differences between the percent of methemoglobin in the normal newborns and percent of methemoglobin in the newborns with acidosis has been found. In addition, no correlations between the base excess and percent of methemoglobin has been observed. On the contrary, two newborns with low glucose-6-phosphate dehydrogenase activity demonstrated a significantly increased methemoglobin content in their red cells. The results of our study do not confirm a key role of acidosis in the mechanism of methemoglobin formation in the neonate. It is likely than impairment of red cell metabolism should be the main factor in the formation of methemoglobin in the first days of life.

Acidosis↗

Correlations between plasma levels of opioid peptides and adrenal androgens in prepuberty and puberty.

In 139 prepubertal children and in 38 pubertal adolescents plasma levels of ACTH, cortisol, beta-lipotropin (BLPH), beta-endorphin (BEP) and dehydroepiandrosterone sulphate (DHAS) were determined by specific radioimmunoassays directly (steroids) or after plasma purification (peptides). ACTH and cortisol concentrations remain stable during both prepuberty and puberty, while DHAS levels constantly increased from 5 to 16 years. Both BLPH and BEP increase from early infancy to late prepuberty when they reach adult values. During puberty both opioids remain constantly within the adult range. BLPH and BEP concentrations were significantly correlated to those of DHAS throughout prepuberty. These data suggest a possible role of BLPH and BEP in and/or other proopiocortin-related peptides in the development of adrenarche, while the lack of particular changes in these peptide levels during sexual maturation seems to exclude their role in gonadarche and pubertal development.

Adolescent↗

Proopiocortin-related peptide plasma levels throughout prepuberty and puberty.

The plasma patterns of ACTH, beta-lipotropin (beta LPH) and beta-endorphin (beta EP), in addition to those of cortisol and dehydroepiandrosterone sulfate (DHAS), were studied in 139 prepubertal children (subdivided into different age groups) and 38 adolescents (subdivided according to Tanner's pubertal stages) aged 10-16 yr. The adult control group was composed of 23 females and 12 males aged 17-40 yr. No sex differences were found in ACTH, beta LPH, beta EP, and cortisol plasma levels. ACTH plasma levels were slightly lower in the 1- to 3-yr-old groups than in males at 4-5 yr and females at 8-9 yr. No further significant differences were observed in any of the age or pubertal groups, the concentrations being constantly in the adult range. beta LPH and beta EP plasma levels were lowest at 1-3 yr in both males (beta LPH: 2.1 +/- 0.25, beta EP: 1.85 +/- 0.59 fmol/ml, mean +/- SE) and females (beta LPH: 2.8 +/- 0.31; beta EP: 2.41 +/- 0.41 fmol/ml); plasma levels of both hormones increased progressively in both sexes until Puberty 1 stage of sexual maturation, at which time levels were 7.3 +/- 0.78 and 8.69 +/- 1.0 fmol/ml in males and 7.1 +/- 0.34 and 6.76 +/- 0.13 fmol/ml in females; these levels are similar to adult values. A highly significant linear correlation was found between both beta LPH and beta EP concentrations and the age of the subjects; this was not true for ACTH plasma levels. Cortisol plasma levels were similar in all groups. DHAS plasma levels increased progressively from 1-3 yr to the end of sexual maturation when adult values were reached. During prepuberty, DHAS levels were significantly correlated with both beta LPH and beta EP, but not ACTH. These data indicate that plasma beta LPH and beta EP concentrations, in contrast to ACTH levels, increase progressively throughout prepuberty and suggest that the processing of the parent proopiocortin molecule or secretion of the processed peptides from the anterior pituitary (or other sources) may change from early infancy to adulthood. Furthermore, the correlation between both beta LPH and beta EP with DHAS plasma levels in prepuberty suggests a role of proopiocortin-related peptides in adrenarche.

Adolescent↗

Possible testicular 3 beta-hydroxysteroid dehydrogenase deficiency in cryptorchid neonates.

In order to explain the impaired neonatal secretion of testosterone (T) in cryptorchid neonates, plasma levels of luteinizing hormone (LH), follicle stimulating hormone (FSH), precursors of T, and T were measured in bilateral cryptorchid and control babies from the first to the 90th day of life. RIA of steroids was performed after plasma ether extraction and celite ethylen glycole column chromatography. In comparison to the neonatal period, plasma LH, dehydroepiandrosterone (DHA), and T were increased in both groups at the 60th day, although cryptorchids showed significantly lower T level (1018 +/- 168 pg/ml) than controls (1985 +/- 410 pg/ml, p less than 0.001). At the same time, androstenedione (A) and 17 alpha-hydroxy-progesterone (17P) remained unchanged. Dihydrotestosterone (DHT) concentrations were higher in cryptorchids in the neonatal period, and increased in both groups at the second to third month of life. The T/DHT ratio was significantly higher in cryptorchids in all age groups. These data indicate that (1) neonatal T formation probably occurs through the delta 5 pathway; (2) impaired T secretion in cryptorchid neonates could be due to a deficiency of 3 beta-hydroxysteroid dehydrogenase; and (3) cryptorchid neonates exhibit an elevated 5 alpha-reductase activity of unknown origin.

3-Hydroxysteroid Dehydrogenases↗

Fetomaternal opioid levels and parturition.

The present study evaluates the plasma level changes in beta-lipotropin and beta-endorphin in nine women at term throughout spontaneous labor, in ten pregnant women undergoing elective cesarean section in the absence of uterine contractions, and in ten women submitted to emergency cesarean section because of fetal distress occurring during labor. A basal plasma sample was taken before labor in the 39th week of pregnancy. Two subsequent samples were then obtained before and after parturition, together with umbilical cord samples at birth. beta-lipotropin and beta-endorphin were measured by radioimmunoassay after silicic acid plasma extraction and gel filtration. In cases of spontaneous labor, there was a progressive increase in opioid concentrations as labor progressed, the maximal values being observed after delivery. Cord values were similar to those observed in the mother, without showing any relationship to them. Pregnant women undergoing cesarean section in the absence of labor show constant beta-lipotropin and beta-endorphin concentrations both before and after fetal extraction, both values being significantly lower than those found at delivery after spontaneous labor. beta-Endorphin neonatal levels were significantly higher than in the respective mothers and were in the same range as those of infants born through vaginal delivery. In the third group (cesarean section performed at the first stage of labor), presurgical opioid levels were higher than in women at the same stage of spontaneous labor, whereas postextraction values showed a wide range, with mean values similar to those observed after spontaneous delivery.(ABSTRACT TRUNCATED AT 250 WORDS)

Apgar Score↗

[The secretion of calcitonin in the newborn infant in relation to the method of delivery].

Determinations of serum (Ca) and calcitonin (CT) were carried out in 80 full term newborn infants. 40 of them were born by elective Caesarean section (ECS) while 40 were born by normal vaginal delivery (VD). Samples of blood were drawn at 1, 24, 48, 168 hours of life. Each newborn was tested no more than twice. Serum Ca of ECS at 24th hour was significantly less than Ca of VD. At the same time CT of ECS was significantly higher than CT of VD. A negative significant correlation between Ca and CT was observed. The data demonstrate the key role of CT in the homeostasis of Ca in the first hours of life. In addition, the results were suggestive for a dependence of CT secretion on the stress of birth.

Calcitonin↗

[The effects of diet on the secretion of calcitonin in the newborn infant].

Determinations of serum calcium (Ca), phosphorus (P) and calcitonin (CT) were carried out in two groups of full term newborn infants: 80 on bottle feeding (group A) and 80 breast feeding (group B). Samples of blood were drawn at 1, 6, 12, 24, 48, 72, 96 and 168 hours of life. Each newborn was tested no more than twice. No differences between the two groups could be detected before the 72th hour. At that time, the Ca of group A was significantly lower than Ca of group B while the CT and P were significantly higher in the same group A. So that, the P serum level appears to be one of the most important factor regulating the homeostasis of Ca after the first 72 hours of life.

Breast Feeding↗

[Separation of erythrocytes from full-term infants into different age populations].

Separation of erythrocytes into fractions of different age was carried out by the method of discontinuous gradient. Five fraction of various specific density were prepared and in each fraction age dependent enzyme activities PK and G-6-PD were assayed. The erythrocytes from cord blood and from newborn 4-5 days old were studied. The results demonstrate the correlation between density and erythrocyte age in both cord blood and blood from newborns. However, 4-5 days old demonstrate a shift of various populations toward fractions of higher density.

Cell Separation↗

[Serum calcitonin in full-term infants].

Determination of calcium (Ca) calcitonin (CT) secretion in mother during labour and their newborns during the first hours of life was carried out. Mean serum levels of Ca decreased after the birth. Mean serum level of Ct was higher in the cord blood comparing with mothers blood. These levels increased after the 6th hour and reached the peak at the 12nd hour. After the 24th hour the CT levels decreased significantly although at the 48th hour they remained higher than those in the cord blood.

Calcitonin↗

[Neonatal adaptive phenomenon: secretion of beta-lipotropin, and beta-endorphin in the first week of life].

beta Lipotrophin and beta Endorphin plasma levels have been measured in 35 newborns subdivided in 5 groups of 12, 24, 48, 72 and 168 hours of life, 10 umbilical mixed blood samples were also evaluated. After plasma extraction (3 ml) and G-75 Sephadex column chromatography, the peptides were measured by two specific RIAs. beta LPH and beta EP levels were high in umbilical cord plasma (241.0 +/- 43.3 and 70.0 +/- 8.5 pg/ml respectively). A progressive decrement was then observed until the 72th hour of life (28.1 +/- 13.2 and 8.7 +/- 4.8 pg/ml respectively) but the elevated levels found at 24th hour demonstrate an active synthesis and release from fetal and neonatal pituitary. After a slight and transient decreased activity during the first week of life, the statistically significant increase of both beta LPH and beta EP observed at seven day indicate that at this moment pituitary function is restored.

Chromatography, Gel↗

Determination of red blood cell superoxide dismutase and glutathione peroxidase in newborns in relation to neonatal hemolysis.

Superoxide dismutase and glutathione peroxidase activities have been determined in newborns. Their mean values are approximately the same as in normal adults. In some cases a low content of superoxide dismutase and/or a high (superoxide dismutase/glutathione peroxidase) ratio are associated with hematological symptoms. In addition, a low superoxide dismutase activity is associated with hyperbilirubinemia and is present in two of the three cases showing maximal acetylphenylhdrazine-induced hemoloysis.

Adult↗

Is the "small world" effect relevant to evolution?

Mutations and selection are the driving forces of biological evolution. We model here the simplest case: an evolving population of asexual organisms. We consider two kinds of mutations: point mutations, corresponding to local displacements in the genotypic space, and all the other genotypic rearrangements, equivalent to long-range jumps. We show that a small-world effect is present in evolution: even a small fraction of quenched long-range jumps makes the results indistinguishable from those obtained by assuming all mutations equiprobable. We apply this result to the evolution of a population on a smooth fitness landscape, showing that the equilibrium distribution is a Boltzmann one, in which the fitness plays the role of an energy, and mutations that of a temperature.

Evolution, Molecular↗