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Biomedical subjects

L Benso

Publications and source records attributed to L Benso.

At least 19 recordsLinked to original sources

Longitudinal distance standards of fetal growth. Intrauterine and Infant Longitudinal Growth Study: IILGS.

BACKGROUND: Most ultrasonographic fetal growth norms are derived from cross-sectional data or from longitudinal data treated as coming from cross-sectional studies, although only longitudinal models may detect particular aspects of fetal growth shape, such as peak of growth velocity. MATERIALS AND METHODS: The sample included 238 singleton normal pregnancies. All the fetal traits under study (biparietal diameter, occipito-frontal diameter, head circumference, femur diaphysis length and abdomen circumference) were measured according to the classical ultrasound techniques by highly trained operators. Individual growth profiles (made up of 5 to 9 measures) were taken at regular intervals between the 12th and the 40th week. Growth norms were traced by means of a two-stage linear model: (I) a 3-constant fetal growth function was fitted to each individual growth profile, (II) growth centiles were based upon the weighted mean and covariance matrix of the individual growth constants. RESULTS: Fetal growth curves show a sigmoid shape with a maximum slope (i.e. a peak growth velocity) which occurs earlier for head diameters (about 18 weeks), later for femur diaphysis length (20 weeks) and abdomen circumference (22 weeks). During intrauterine growth, all traits show a progressive increase in interindividual variability, which is more prominent for abdomen circumference. CONCLUSION: The mathematical model applied to a large sample of growth profiles provided a satisfactory description of the individual fetal development and its biological variability, and allowed the construction of longitudinal distance standards useful for clinical purposes.

Abdomen↗

Is the persistence of isolated GH deficiency in adulthood predicted by anatomical hypothalamic-pituitary alterations?

The aim of this study was to verify the persistence in adulthood of GH deficiency diagnosed in childhood and treated with hGH in childhood and to study whether anatomical hypothalamic-pituitary alterations evaluated by magnetic resonance (MR) imaging could predict it. To this goal, in six GHD adults (3 males and 3 females aged 17.2-24.5 yr, BMI 21.8 +/- 1.3), we studied anterior pituitary hormone response to GHRH (1 microgram/kg iv)+pyridostigmine (120 mg po)+ GnRH (100 micrograms iv) +TRH (400 micrograms iv)+hCRH (100 micrograms iv) as well as brain MR imaging. In childhood, the diagnosis of severe isolated GHD had been done based on auxological findings as well as on GH response < 7 micrograms/L after two classical provocative stimuli. In the present study, hormonal responses showed the persistence of severe isolated GHD in 4 out of 6 patients (peak, mean +/- SEM: 3.8 +/- 0.6, range 2.6-4.8 micrograms/L). In these patients, IGF-I levels were found low or low-normal. In other 2 patients, a clear GH response to stimulation (peak: 51.3 and 43.0 micrograms/L, respectively) together with normal IGF-I levels were found. No other anterior pituitary hormone deficiency was present in all subjects. MR imaging showed pituitary hypoplasia in all patients with persistent GHD; in 2 out of them, pituitary stalk interruption and ectopic neurohypophysis was also present. On the other hand, MR imaging showed normal hypothalamo-pituitary morphology in the 2 subjects with normal somatotrope response. In conclusion, our present data indicate that testing with a potent stimulus such as GHRH+pyridostigmine is a reliable method to assess the persistence of GH deficiency which associates with anatomical hypothalamic-pituitary alterations at the MR imaging. Patients with transient GH deficiency in childhood and normal pituitary GH reserve in adulthood have normal hypothalamic-pituitary MR imaging.

Adolescent↗

Variation of bone age progression in healthy children.

Bone age assessments were related to auxological variables in 407 Italian boys, between 7 and 12 years of age, in order to elucidate the factors that affect the rate of skeletal maturation and to examine the possibility of using measures of skeletal maturation of evaluate individual patients. Using the radius-ulna-short bones (RUS) method of assessment, bone age velocity was greater in the Italian boys than for the UK reference standards, although there was considerable interindividual dispersion around the mean. Bone age velocity and height velocity were poorly correlated, and there was little correlation between skeletal and pubertal maturation. There was a slight positive correlation between bone age velocity and height SDS and between bone age velocity and body mass index. Bone age estimations using RUS were greater than those obtained using the carpus. In conclusion, the marked interindividual deviation in measured bone ages makes it difficult to relate data on an individual basis to other measures of growth and maturation

Age Determination by Skeleton↗

Main problems associated with bone age and maturity evaluation.

In scientific papers, skeletal maturation-expressed as bone maturity scores or bone age-is often used as a quantifiable variable similar to height or weight. This paper discusses whether this approach is appropriate. The questions addressed are whether skeletal maturation can be measured on a quantitative scale, whether its use is appropriate in computing, and what the 'numbers' used represent. Reference will be made mainly to the Tanner-Whitehouse method, which, in the opinion of the authors, has been the most reliable method of assessment to date. Many of the remarks made in this paper may be extended to other methods of assessment, and have been stressed by Tanner himself. The authors are aware that, in the future, some of the remarks could be made redundant by the development of more detailed definitions of bone maturation. This is becoming feasible with the advent of expert systems for the automatic recognition of different stages of bone maturation.

Adolescent↗

Growth velocity monitoring of the efficacy of different therapeutic protocols in a group of thalassaemic children.

Since intensive chelating therapy for thalassaemic children was introduced, growth rates appear to have diminished. To investigate what factors were responsible we compared velocities of growth in length over a period of 1 year between groups distinguished by different strategies of treatment. Forty-two thalassaemic patients, 30 males aged 4-12 years, and 12 females, 4-10 years old, were assigned from their current treatment into subgroups based upon blood ferritin levels, daily dose of desferrioxamine and urinary zinc levels. CONCLUSION The results confirm that a reduction in desferrioxamine results in greater growth. If blood ferritin is low, the change effect may be greater. Secondly, any zinc deficiency should be treated. The changes in treatment convert a growth velocity of -2 to -3 SDS to a velocity of about -1 SDS.

Chelation Therapy↗

Growth hormone-releasing activity of hexarelin, a new synthetic hexapeptide, before and during puberty.

The objective of this study was to verify the GH-releasing activity of a synthetic hexapeptide, hexarelin (HEX), before and during puberty. Ninety-six children (54 boys and 42 girls, aged 4.1-17.4 yr) were studied. Fifty-two of the children were prepubertal, and the other 44 were in pubertal stage II-IV. The GH response to 2 micrograms/kg HEX, iv (n = 56), was higher (P < 0.001) than that induced by 1 microgram/kg GHRH, iv (n = 33). The iv dose of 2.0 micrograms/kg HEX induced a greater GH increase (P < 0.02) than the 1.0 microgram/kg dose. The GH-releasing effect of 10 mg HEX, orally, was greater (P < 0.03) than that of 1.0 microgram/kg GHRH, iv (n = 7). The iv dose of 2 micrograms/kg HEX elicited an increase in GH levels that was higher in pubertal children than in prepubertal children (77.5 +/- 8.5 vs. 39.4 +/- 4.4 micrograms/L; P < 0.001). Before puberty, there was no sex-dependent difference in the GH response to HEX. It increased during puberty (P < 0.05 and P < 0.002 for boys and girls, respectively), when it was higher (P < 0.05) in girls than in boys. In contrast, GH responses to GHRH were not related to sex differences and/or puberty. In conclusion, HEX is a potent and reproducible stimulus of GH secretion in children. The effect of HEX increases in puberty, with girls showing a more marked GH response.

Adolescent↗

Turner's syndrome in Italy: familial characteristics, neonatal data, standards for birth weight and for height and weight from infancy to adulthood.

In 1990, the Italian Study Group for Turner's Syndrome (ISGTS) undertook a nationwide survey, involving the retrospective collection of cross-sectional data and longitudinal growth profiles of 772 girls with Turner's syndrome born between 1950 and 1990. The study was carried out in 29 pediatric endocrinological centers. In this first report, the familial characteristics and neonatal data of Turner girls are described, compared to those of the general population, and related to postnatal somatic development. Furthermore, charts for birth weight and growth standards for height and weight from infancy to adulthood are presented (these are the first charts based on a large sample from the Mediterranean area). The main findings were: (1) incidence of Turner births increases with parental age or parity; (2) most of the neonates are small for dates; (3) girls with normal birth weight tend to be both taller and heavier than girls with low birth weight during the whole growth period; and (4) a 10-cm difference in midparental height leads to a 6.5-cm difference in adult stature.

Adolescent↗

Final height in sexually precocious girls after therapy with an intranasal analogue of gonadotrophin-releasing hormone (buserelin).

Twenty-two girls affected by sexual precocity with impaired final height prognosis were followed until they achieved final height. Twelve of them were treated with an intranasal (D-Ser6)-gonadotrophin-releasing hormone (GnRH) analogue (buserelin) administered at a mean dose of 25 micrograms/kg/day (range 20-32) for a mean period of 14 months (range 8-18). Ten girls refused treatment. Mean final height of the treated girls was 157.3 +/- 8.2 cm, significantly (p = 0.03) higher than the 149.7 +/- 5.5 cm of untreated patients. Treated girls surpassed midparental height (+1.7 cm) while untreated girls reached the lower part of target zone (-3.5 cm). Our data suggest that intranasal buserelin treatment preserves final height in girls with sexual precocity and initially impaired height prognosis.

Administration, Intranasal↗

Dose-dependent effects of deflazacort and prednisone on growth and skeletal maturation.

Deflazacort (DFZ), a new glucocorticoid which has recently become available, is expected to have less negative effects on growth and skeletal maturation than conventional steroids, in children treated long term. To verify this hypothesis, a multicentre trial was organized to evaluate the effects of DFZ vs prednisone (PDN) on statural growth and skeletal maturation in a group of prepubertal children requiring glucocorticoid therapy for at least 6 months/year. The results of an analysis of 55 children (aged 3-12 years, 24 with connective tissue disease and 31 with kidney glomerular disorders) treated randomly with either DFZ (31 patients) or PDN (24 patients) and followed for a mean period of about 22 months (16 months under steroid therapy) are presented. The observation period was split up into the following phases according to dose and administration regimen: daily, high-dose therapy; alternate-day, high-dose therapy; low-dose therapy; suspension of treatment. The height, statural age, skeletal age and body weight velocities (i.e. the increase/year) were considered. In spite of large intra-individual and inter-individual variability, the results suggest that DFZ has a lower negative impact on indicators of growth. During high-dose daily administration, the height velocity tended to be lower in the PDN group and the impairment of skeletal maturity was significantly less for DFZ than for PDN. During an alternate-day regimen, height velocity was slightly higher in the PDN group and skeletal age velocity was higher in the DFZ group. It seems that steroid effects on statural growth and bone maturation occur in parallel.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Determination by Skeleton↗

Magnetic resonance and the diagnosis of short stature of hypothalamic-hypophyseal origin.

Magnetic resonance imaging was performed in 23 patients with short stature (7 had multiple pituitary hormone defect, 11 had isolated growth hormone deficiency and 5 had normal variant short stature) to investigate if there is a relation between magnetic resonance findings and results of endocrine tests. Magnetic resonance imaging of patients with multiple pituitary hormone deficiency or with serious isolated growth hormone deficiency (growth hormone < 3 micrograms/l) revealed an interrupted pituitary stalk and ectopic neurohypophysis or a mass. In patients with less serious isolated growth hormone deficiency (growth hormone > 3 micrograms/l) or with normal variant short stature, the technique revealed a normal or hypoplastic hypophysis. Magnetic resonance appears to be a useful second-level diagnostic tool in defining the type of alteration in growth defects of endocrine origin.

Adolescent↗

The effect of galanin on baseline and GHRH-induced growth hormone secretion in obese children.

We have evaluated the effect of the administration of galanin (Gal), a newly identified hypothalamic peptide, on baseline and GHRH-induced GH rise in five obese children and in seven controls. The GH response to GHRH (hpGRF(1-29), 1 microgram/kg i.v.), and to Gal (15 micrograms/kg/h for 1 h), evaluated both as the maximum GH peak and as integrated area under the curve (AUC), was significantly lower in the obese children than in the controls. Simultaneous administration of Gal plus GHRH significantly increased the GH response to GHRH in all the obese subjects, so that their mean peak GH levels and AUC after Gal plus GHRH were similar to those of the control children after GHRH. Also, in control children Gal caused a significant augmentation of the GH response to GHRH. Mean peak GH levels and mean AUC after Gal plus GHRH were significantly higher in the controls than in the obese children given the same treatment. Our data indicate that obese children have a blunted GH response to Gal, which, however, is able to enhance the GH response to GHRH. This observation strengthens the view that the mechanism of action of Gal involves modulation of endogenous somatostatin (SRIH) release. In addition, similarity between the effects of Gal and pyridostigmine on baseline and GHRH-stimulated GH release in obese children may indicate the existence of a cholinergic link in the action of Gal.

Child↗

Evidence for involvement of endogenous somatostatin in the galanin-induced growth hormone secretion in children.

We have evaluated the effects of the combined administration of Galanin (Gal) plus growth hormone-releasing hormone (GHRH) and of pyridostigmine (PD), a cholinergic agonist, plus Gal on GH secretion in 15 children (12 males and three females, age 7.7-14.5 y) with short stature. Children were subdivided into two groups. In group 1 (n = 7) Gal (15 micrograms/kg h i.v.) plus GHRH (1 microgram/kg i.v.) administration induced a higher GH rise (peak = 73.1 +/- 10.2 ng/mL, mean +/- SD; area under the curve (AUC) = 531.9 +/- 78.7 ng.min.mL-1) than did GHRH alone (peak = 38.9 +/- 26.5 ng/mL, p less than 0.05; AUC = 256.9 +/- 165.6 ng/mL/min-1, p less than 0.005). Gal had a synergistic effect on the GHRH-induced GH response because the GHRH plus Gal AUC response was significantly higher (p less than 0.01) than the sum of the areas of response to GHRH and Gal alone. In group 2 (n = 8) PD administration (60 mg/kg p.o.) had no significant effects on the Gal-induced GH secretion (peak = 14.9 +/- 8.8 and 16.0 +/- 9.8 ng/mL after Gal and PD + Gal, respectively; AUC = 91.2 +/- 52.1 and 125.2 +/- 83.6 ng.mL.min-1 after Gal and PD + Gal, respectively). Our results confirm the ability of Gal to stimulate GH secretion in children, and strengthen the view that its mechanism of action involves modulation of endogenous somatostatin release.

Adolescent↗