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Biomedical subjects

R Di Toro

Publications and source records attributed to R Di Toro.

At least 37 records · Page 2Linked to original sources
PubMed1999

Long-term zinc and iron supplementation in children of short stature: effect of growth and on trace element content in tissues.

We evaluated the effect of one year of supplementation with iron plus zinc (12 mg/day of Fe+++ and 12.5 mg/day of Zn++), zinc alone (12.5 mg/day of Zn++) and placebo on growth and on the iron, zinc, copper and selenium tissue contents in 30 well-selected children of short stature (16 M and 14 F; 4-11 years old). Before and after supplementation, we measured the concentrations of iron, transferrin, ferritin, zinc and copper in serum, of zinc in erythrocytes and leukocytes, and of zinc, copper and selenium in hair, as well as glutathione peroxidase activity in erythrocytes. Before supplementation, ferritin and serum, erythrocyte and hair zinc contents were significantly lower than in age-matched controls, while the other measured indices were in the normal range. Iron plus zinc supplementation caused an improvement in growth rate in all subjects, i.e., the median Z-score increased from -2.22 +/- 0.45 to -0.64 +/- 0.55; (p < 0.01). In the zinc-supplemented group, only the subjects whose ferritin levels were higher than 20 ng/L before supplementation showed a similar improvement of growth rate. Iron plus zinc supplementation could be a reasonable treatment in short, prepubertal children affected by marginal zinc and iron deficiency.

Age Determination by Skeleton↗
PubMed1999

Epidemiological study of blood lead levels of children and adolescents living in Campania, Italy.

The aim of the present study is to evaluate blood levels (PbB) in a group of 500 (245 M, 255 F) children and adolescents of Campania (Italy) aged from 0.197 to 16.915 years, 269 (136 M, 133 F) of whom lived in urban zones and 231 (109 M, 122 F) in rural zones. PbB was assayed by electrothermal atomic absorption spectroscopy. The parents of the examined subjects children were interviewed about common risk factors for lead exposure using a standardized questionnaire. The PbB of children living in urban zones were significantly higher than the PbB of those living in rural zones (60.0 +/- 3.0 mg/L vs. 40.0 +/- 2.0 mg/L, p < 0.001). A PbB higher than 100 mg/L was found in 27 children (5.4%). We observed a significant correlation between age and PbB (p < 0.001, r = 0.529). Our data regarding children and adolescents demonstrate that the prevalence of PbB higher than 100 mg/L is greater in children living in urban areas (6.89%) than in subjects living in rural areas (3.89%). The findings can be explained by the higher presence of risk factors of Pb exposure in urban areas. Our data, if compared with those of previous studies concerning children of Campania, show a clear decrease of PbB. The correlation that we found between age and PbB indicates that long-term exposure at low doses more than a more intensive but short-term exposure seems to be important for the increase of blood lead levels.

Adolescent↗
PubMed1999

Renal calyceal microlithiasis: clinical presentation may precede sonographic evidence.

Calyceal microlithiasis (CM) is characterized by the sonographic finding of hyperechogenic spots less than 3 mm in diameter in renal calyces, and it may be the first step in calculus formation. From January 1992 to January 1998, we have observed 216 children with CM. The present report deals with 34 of them in whom renal sonography was negative at first observation and the diagnosis of CM was made only on repeated sonographic examinations. The presenting symptoms were recurrent abdominal pain, dysuria, and hematuria occurring alone or in combination. Half of the patients had hypercalciuria. A history of urolithiasis in at least one first- or second-degree relative was present in 85% of patients. Renal sonography was repeated after 6-22 months (mean 11) and showed unilateral CM in 16 subjects and bilateral in 18. The finding of CM may be preceded by a period of time when symptoms and/or signs are present while microcalculi are not yet detectable. Repeated ultrasound examinations may be needed not only in patients with hypercalciuria but also in those with recurrent abdominal pain, dysuria, and/or hematuria not associated with hypercalciuria.

Calcium↗
PubMed1999

Sigma1 recognition sites in rabbit iris-ciliary body: topical sigma1-site agonists lower intraocular pressure.

In this study, we examined the presence of sigma1 and sigma2 sites in the rabbit iris-ciliary body by receptor binding and investigated their effects on intraocular pressure (IOP) in albino rabbits. The iris-ciliary body has binding sites for the sigma1-site agonist [3H](+)-pentazocine (Kd = 4.6 nM; Bmax = 212 fmol/mg protein) and sigma2 sites labeled with [3H]1,3-di-o-tolylguanidine (DTG) (Kd = 8. 2 nM; Bmax = 1120 fmol/mg protein). In competition binding studies, (+)-pentazocine and the sigma antagonist NE-100 displayed high affinity for sigma1 sites (Ki = 2.1 and 2.4 nM, respectively), whereas (+)-N-allylnormetazocine (NANM) was less potent (Ki = 178 nM). Unilateral topical (+)-pentazocine (0.01-0.1%) caused a significant dose-related reduction of IOP in ocular normotensive rabbits and in the alpha-chymotrypsin model of ocular hypertension. (+)-NANM was less potent than (+)-pentazocine. Neither compound altered the IOP of the contralateral eye, and their hypotensive activity was blocked by NE-100 that, by itself, had no effect on IOP. (-)-Pentazocine, (-)-NANM, and DTG had no effect on IOP. DTG prevented the hypotensive effect of (+)-pentazocine, suggesting that it acts as a sigma1-site antagonist. sigma-Site ligands did not affect pupil diameter or cause ocular inflammation. Topical [3H](+)-pentazocine reaches the intraocular tissues within 30 min, and its uptake in the iris-ciliary body and retina was significantly reduced by topical pretreatment with NE-100, as expected for a receptor-specific agent. Reverse-phase HPLC confirmed the presence of intact (+)-pentazocine in iris-ciliary body homogenates. sigma1-Site agonists may offer a novel class of agents potentially effective in the control of ocular hypertension.

Animals↗
PubMed1998

Regulation of delta opioid receptors by delta9-tetrahydrocannabinol in NG108-15 hybrid cells.

In this study we employed the neuroblastoma x glioma NG 108-15 cell line as a model for investigating the effects of long-term activation of cannabinoid receptors on delta opioid receptor desensitization, down-regulation and gene expression. Exposure of NG 108-15 cells to (-)-delta9-tetrahydrocannabinol (delta9-THC) reduced opioid receptor binding, evaluated in intact cells, by approximately 40-45% in cells exposed for 24 h to 50 and 100 nM delta9-THC and by approximately 25% in cells exposed to 10 nM delta9-THC. Lower doses of delta9-THC (0.1 and 1 nM) or a shorter exposure time to the cannabinoid (6 h) were not effective. Down-regulation of 6 opioid receptors was not observed in cells exposed for 24 h to pertussis toxin (PTX) and then treated for 24 h with 100 nM delta9-THC. In cells that were exposed for 24 h to the cannabinoid, the ability of delta9-THC and of the delta opioid receptor agonist [D-Ser2, Leu5, Thr6]enkephalin to inhibit forskolin-stimulated cAMP accumulation was significantly attenuated. Prolonged exposure of NG 108-15 cells to 100 nM delta9-THC produced a significant elevation of steady-state levels of delta opioid receptor mRNA. This effect was not observed in cells pretreated with PTX. The selective cannabinoid receptor antagonist SR 141716A blocked the effects elicited by delta9-THC on delta opioid receptor desensitization, down-regulation and gene expression; thus indicating that these are mediated via activation of cannabinoid receptors. These data demonstrate the existence, in NG 108-15 cells, of a complex cross-talk between the cannabinoid and opioid receptors on prolonged exposure to delta9-THC triggered by changes in signaling through Gi and/or G0-coupled receptors.

Animals↗
PubMed1998

[Epidemiological study of blood lead levels in young subjects in the Campania region: preliminary data].

Blood lead levels were assayed in 261 children (133 males and 128 females) living in Campania, 137 (63 females and 74 males) in urban areas and 124 (65 females and 59 males) in rural zones, aged between 0.197 and 16.863 years. Blood lead determination was carried out by electrothermal atomic absorption spectroscopy. All children were interviewed about common risk factors for lead exposure. PbB (median +/- SD) were significantly higher in the urban than in the rural population (6.0 +/- 0.31 vs 3.75 +/- 0.25 micrograms/100 ml; p < 0.001). The frequency of blood lead level above 10 micrograms/100 ml was 4.21% in our tested group, i.e., significantly lower than in previous studies. A significant direct correlation between blood lead levels and age was found (r = 0.47; p < 0.001). In agreement with the literature on this subject, our findings show a significant reduction with time, of blood lead levels of children and adolescents in our region. Time of exposure more than total dose seems to be important for the increase of blood lead level.

Adolescent↗
PubMed1996

Trace elements in hair of healthy children sampled by age and sex.

Hair trace element (TE) (Cr, Mn, Fe, Zn, Cu, Br, Rb, Sr, Pb) levels from 336 healthy subjects were measured by the Proton-Induced X-ray Emission (PIXE) method. The subjects were divided in three groups: 157 full-term neonates (75 male and 82 female), 86 children (41 male and 45 female) ages 6 to 11 yr, and 93 adolescents (51 male and 42 female) 11 to 16 yr old. Cu, Zn, Cr, and Br show an increase from birth to 8 yr and then decrease. Fe, Mn, and Sr strongly decrease up to 8 yr and then remain almost stable. Sex differences are present in Fe, Zn, and Br of children and in Cu, Cr, and Br of adolescents.

Adolescent↗
PubMed1994

Interaction of trace elements in a longitudinal study of human milk from full-term and preterm mothers.

Concentrations of 8 trace elements (Fe, Cu, Zn, Se, Br, Pb, Rb, and Sr) at different lactation time were measured by the PIXE multi-elemental technique. Time dependence and interelement correlations were studied. A total of 200 milk samples from 32 lactating mothers were supplied from 2 to 120 d after delivery of 26 full-term and 6 preterm infants. All elements showed a lognormal frequency-distribution. The Fe, Cu, Zn, and Se contents in preterm milk were found to be somewhat different with respect to full-term milk. Cu, Zn, Se, Br, Pb, and Rb concentrations declined with lactation time, both in pre- and full-term samples. Sr and Fe contents did not show any change with time. Detailed analysis of data by partial correlation and multiple regression methods was performed. No substantial differences between preterm and full-term samples were found in the results of partial correlation analysis. Cu and Zn were found to be correlated with lactation time, whereas the measured time dependence for the other elements has to be attributed to the effect of the existing interelement correlation. All the measured elements appeared to be correlated with at least one other element. In particular, Se was inversely correlated with Zn and directly with Cu. The zinc and copper contents in milk can therefore depend on the variation in the mother selenium intake.

Adolescent↗
PubMed1994

Follow-on formulae.

Follow-on formulae are recommended as part of the liquid intake of the weaning diet for infants from 6 months on and children aged 12-36 months. The amount of energy and nutrients absorbed by infants from Beikost and milk differs enormously depending on a number of factors and therefore the recommended composition of follow-on formulae varies accordingly. In the future a greater understanding of the nutritional needs of infants and the possibility of choosing between high- or low-protein content formulae may provide infants with a better balanced diet.

Energy Intake↗
PubMed1993

Trace element content of human milk during lactation.

Human milk is believed to provide all the nutrients necessary for normal infant growth. The present study is concerned with the evaluation of longitudinal changes in Fe, Cu, Zn, Se, Br, Pb, Rb, and Sr milk contents over a long period of lactation. A total of 140 milk samples from 26 lactating mothers were supplied from the 2nd to the 180th day after delivery of a full-term healthy infant. Cu, Zn, and Se showed a time-dependent decrease, with similar 10-day half-times. Br and Pb showed correlations with time, but the data fitting produced very short (2-3 days) half-times. The Fe, Rb, and Sr contents were constant over the lactation time. After about one month of lactation, trace element contents tend to stabilise, as do other milk components.

Adolescent↗
PubMed1992

Delayed pubertal growth spurt in glomerulopathic boys receiving alternate-day prednisone.

Statural growth was studied in 16 glomerulopathic children, 12 boys and 4 girls, treated with alternate-day prednisone for more than 2 years. Five patients were older than 12 years when started on therapy. Growth velocity was significantly slower in boys who received therapy during peripubertal age than in younger boys taking similar amounts of prednisone. In boys, pubertal growth spurt was delayed and shorter than normal, but growth continued with a velocity greater than normal for some years and kept on after 19 years of age. The ultimate height of the patients followed up after 19 years of age ranged within the normal limits of genetic height potential.

Adolescent↗
PubMed1992

Trace elements in full-term neonate hair.

Proton Induced X-ray Emission (PIXE) was employed to measure simultaneously the concentration of 12 trace elements in the hair of 141 AGA newborn infants at term. Log-normal distributions were measured for all elements. There were no significant differences in trace elements in relation to sex, gestational age and body weight. The geometric means (mg/kg) were: Cr, 1.5 +/- 0.2; Mn, 1.5 +/- 0.1; Fe, 51 +/- 4; Ni, 1.0 +/- 0.2; Cu, 6.1 +/- 0.3; Zn, 133 +/- 3; As, 0.055 +/- 0.005; Se 0.81 +/- 0.05; Br, 1.3 +/- 0.1; Pb, 1.4 +/- 0.2; Rb, 0.22 +/- 0.03; and Sr, 1.5 +/- 0.2. Some direct and inverse partial correlations among elements were found at different levels of significance. Each element was significantly correlated with at least one other. Zinc and copper concentrations were lower compared to data in the literature. The high values of chromium and selenium concentrations were in agreement with previous findings. The manganese level was in accordance with previous data. The Zn/Cu ratio agreed very well with the data in the literature. This indicates that while concentration values may be subjected to large variations due to living conditions, correlations could be more stable and therefore offer insight on the regulatory mechanisms governing trace element metabolism in man.

Copper↗
PubMed1991

Normal response to anti-HBV vaccination in children with chronic renal insufficiency.

Anti-HBV vaccination was performed in 17 children with chronic renal insufficiency on conservative treatment and in 29 control children. The response to vaccination was satisfactory in patients as well as in the control group and no significant difference was found between the two groups as to percentage of responders and to the titre of HBsAb produced. It appears reasonable to vaccinate all patients with chronic renal insufficiency before they reach end-stage renal disease in areas with high prevalence of HBV infection.

Child↗
PubMed1990

Impaired zinc metabolic status in children affected by idiopathic nephrotic syndrome.

Zinc content of serum, hair and erythrocytes, urinary zinc excretion, zinc clearance (CZn) and the ratio of CZn to creatinine clearance (CCr) (CZn/CCr) were measured in 32 children aged between 2.1 and 14.4 years suffering from idiopathic nephrotic syndrome (INS) without renal failure (CCr greater than 70 ml/min 1.73 m2 body surface area). Nineteen subjects had proteinuria and the remaining 13 were in remission. All children received calcium and vitamin D supplementation while on steroid therapy. There was high dietary zinc and protein intake. The results were compared with those obtained from 19 healthy subjects (aged 2-14 years). Zinc concentration in serum, erythrocytes and urine were measured by a colourimetric method. Proton induced X-ray emission was used to determine zinc content in hair. In patients both with and without proteinuria, the mean contents of serum, hair and erythrocytes were significantly lower than in the control group. The urinary zinc excretion, CZn and CZn/CCr in INS children were significantly higher than in the control group. A positive correlation was found between urinary zinc and protein excretion. In spite of high dietary zinc intake and normal intestinal absorption, children with INS had a zinc deficiency. This was probably caused by an increased urinary zinc loss.

Adolescent↗