Search PubMed⌕ Search

Biomedical subjects

M Bozzola

Publications and source records attributed to M Bozzola.

At least 109 records · Page 6Linked to original sources
PubMed1985

Neonatal serum growth-promoting activity measured in human lymphocytes: comparison of cord and capillary blood.

The growth-promoting activity of serum was studied in 47 normal full-term newborns, comparing the effects of cord and of capillary serum upon the 3H-thymidine uptake into activated adult human lymphocytes. At birth the mean +/- SEM (TA) was significantly higher (P less than 0.001) in capillary serum (1.26 +/- 0.08 U/ml) than in cord blood (0.88 +/- 0.05 U/ml), the individual values being significantly correlated. The relatively low values in cord blood do not result from the presence of an inhibitor, nor from the cortisol levels. It may be concluded that study of cord blood is not the best means to measure growth-stimulating factors in newborns.

Blood Specimen Collection↗
PubMed1985

Serum growth-promoting activity in human newborns. Relationship of thymidine activity with birth weight and the length of gestation.

Thymidine Activity (TA) was measured by the effect of serum upon incorporation of 3H-thymidine into human lectin-activated lymphocytes in 54 newborns: 32 full-term, 11 pre-term and 11 with intra-uterine growth retardation (IGR). Capillary blood was collected at 0-6 hours, with routine samplings. TA values were lower in preterm (0.476 +/- 0.079 U/ml) than in IGR (0.910 +/- 0.118 U/ml, p less than 0.01) and in full-term neonates (1.237 +/- 0.60, p less than 0.001), and also in IGR newborns than in newborns of normal weight (p less than 0.025). In preterm neonates TA was significantly correlated with gestational age (r = 0.715, p less than 0.02), but no such correlation existed in IRG and full-term neonates. When TA values were plotted against birth weight, a correlation was found in preterm (r = 0.715, p less than 0.02) and in IGR newborns (r = 0.714, p less than 0.02), but not in full-term neonates. Longitudinal study up to 21 days did not show significant changes in full-term newborns, while in preterm and IGR neonates TA increased progressively to reach normal values at the 21st day. The correlations observed in newborns between TA, birth weight and gestational age, and the postnatal normalization in newborns with low birth weight, show that TA directly reflects the nutritional state of the fetus.

Birth Weight↗
PubMed1985

Bioassay of growth-stimulating activity of serum: comparison of lymphocyte and cartilage assays in normal and growth hormone-deficient children.

The somatomedin and/or growth-stimulating activity of serum from hypopituitary children and short children with normal growth hormone (GH) response to stimulation tests were studied using different bioassays: thymidine incorporation into human activated lymphocytes; sulfate incorporation into chick embryo cartilage; and simultaneous thymidine uptake into the same cartilages. The results showed that lymphocyte assay is highly sensitive to small amounts of serum and is GH-dependent in children with low GH secretion. On the contrary, the cartilage assays need higher serum concentration and their GH-dependence appears only in subjects with normal or low-normal GH secretion. The lack of correlation between the results of the three bioassays suggests that they measure both somatomedins and different serum factors involved in the regulation of growth.

Adolescent↗
PubMed1985

Serum growth-promoting activity measured as [3H]thymidine incorporation into human activated lymphocytes and serum transferrin levels in newborns and mothers.

Serum growth-promoting activity measured as [3H]thymidine incorporation into human activated lymphocytes and serum transferrin levels were measured during the perinatal period in newborns and mothers. Both thymidine activity (TA) and transferrin levels were significantly increased at the time of delivery in mothers compared to control women, and there was a progressive return to control levels in the first 5 postpartum days. A significant correlation was found between TA and placental weight. In the newborns, TA was low in cord blood after vaginal delivery but not in the cord blood from babies born by cesarean section. In premature newborns, TA was lower than in full term newborns. In all newborns during the first 24 postnatal hours, there was an increase in TA with levels rising above adult control values: levels in cord blood were positively correlated with birth weight but not with thymidine activity. These data afford complementary insights into the humoral controls of growth in newborn infants.

Adult↗
PubMed1985

Serum thymidine activity and insulin-like growth factors in the neonatal period.

Growth-promoting activity measured as [3H] thymidine incorporation into lectin-activated lymphocytes was determined simultaneously with radioimmunoassayable IGF I and IGF II in cord and capillary blood collected from human neonates 30 min and 24 h after birth. All the parameters studied in cord blood were lower than in normal adults. During the early postnatal period, IGF I decreased and IGF II remained unchanged, but thymidine activity increased above the normal adult level. The differences between the values found in cord blood and in capillary blood collected within the first 1/2 h after birth agree with a production of growth factors by the infant. All these growth factors may play a role in foetal growth, as suggested by their correlation with birth weight. Finally, factors other than IGFs contributing to thymidine activity may play a role in neonatal growth since they are higher in newborns than in adults.

Age Factors↗
PubMed1985

Growth-promoting activity of serum throughout pregnancy and at delivery: evaluation by three different bioassays.

Somatomedin evolution has been studied by employing three different bioassays in 181 pregnant women from the 7th week of gestation to delivery and in 18 women during the course of labor. In 105 additional mothers of full-term or pre-term neonates a significant increase of a serum growth-promoting activity (thymidine activity) was observed at delivery, as compared to nonpregnant controls, with a progressive return to normal levels in the post-partum period. Different results were found according to the assay method used, suggesting the multiplicity of growth factors and specific adaptations related to the stages of pregnancy.

Biological Assay↗
PubMed1984

[Stimulating action of human serum on the incorporation of tritiated thymidine in human lymphocytes activated by lectins: demonstration of the GH-dependency and its limitations].

Using thymidine uptake by activated human lymphocytes to measure the growth-stimulating activity of human serum, the authors demonstrate that thymidine activity was significantly correlated (p less than 0.001) with GH levels. r = 0.729 when GH values are below 3.5 ng/ml, r = 0.509 when GH values are below 8 ng/ml and r = 0.337 for all of the patients. Low levels of GH are sufficient for the generation of this activity.

Adolescent↗
PubMed1982

Age-related variation in growth-promoting activity human plasma measured in human lymphocytes.

The age-related variations in the growth-promoting activity of human plasma have been studied from birth (cord blood) to adulthood using a bioassay which measures the incorporation of tritiated thymidine into lectin-activated human lymphocytes. Cord blood values were low (0.69 +/- 0.004 U/ml). A definite increase was found at 5 days of age, correlating with the level at birth. Higher levels were attained after 1 month of age, with a 2-fold increase during the first months of life. Lower values were found in children 1-10 yr old, and high levels were found during puberty. This pattern, different from those of sulfation activity and plasma somatomedins suggests that factors other than somatomedins may be involved in growth stimulation during the first year of life in humans.

Adolescent↗
PubMed1981

Preferential maternal derivation in inv dup(15): analysis of eight new cases.

Eight patients are reported with a de novo extra inverted duplicated chromosome 15. The abnormal chromosome was considered to be the same in all cases, but its precise delineation remained uncertain and was defined as either 15pter leads to 15q12::15q12 leads to 15pter or 15pter leads to 15q11::15q13 leads to 15pter. Analysis with various techniques of the satellite regions of the bisatellited chromosomes demonstrated maternal derivation in six and paternal derivation in one of the seven families. A non-sister chromatid exchange between the two homologous chromosomes 15 is considered a likely origin of the inv dup(15) in the cases with maternal derivation; in the only case of paternal derivation, however, the abnormal chromosome originated from one single chromosome 15. The clinical findings confirm that patients with inv dup(15) have mental and developmental retardation and are frequently affected by seizures, while severe physical malformations are absent.

Abnormalities, Multiple↗