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Biomedical subjects

S Politano

Publications and source records attributed to S Politano.

9 recordsLinked to original sources

Plasma catecholamine levels in children.

While blood norepinephrine and epinephrine levels are well established in adults, literature data concerning concentrations in young children are conflicting. This situation prompted us to assay plasma catecholamines in 86 healthy subjects aged two days to fifteen years using a sensitive high-performance liquid chromatography technique with electrochemical detection. Norepinephrine and epinephrine concentrations remained elevated up until 24 months of age, then dropped progressively to adult levels between 24 and 36 months, with fluctuations. These fluctuations, which reflect the sensitivity of children to environmental factors, prevented demonstration of any catecholaminergic secretory abnormality by blood assays in subjects under two years of age. Urinary assays, for which established values exist, are the only applicable procedure in such patients.

Adolescent↗

Methylated catecholamine metabolites for diagnosis of neuroblastoma.

Assays of urinary catecholamines and their metabolites (HVA, VMA, dopamine) permit biochemical diagnosis of neuroblastoma in approximately 80% of patients. The urinary methylated catecholamine metabolites normetanephrine (NMN), metanephrine (MN), and 3-methoxytyramine (3-MT) were analyzed in 18 patients with neuroblastoma and compared with reference values established for 69 healthy pediatric controls. All 18 neuroblastoma patients had raised urinary excretion of at least one of the three commonly assayed metabolites (HVA, VMA, dopamine). Similarly, raised urinary excretion of a methylated metabolite was noted in all but one of the neuroblastoma patients. The 3-MT level was pathologic in 16 of the 18 patients (89%). In this series, 3-MT assay sensitivity was sufficient to warrant trials on a larger population including comparison with patients considered nonsecretors by routine assay procedures.

Adolescent↗

[Inhaled corticosteroids in the treatment of childhood asthma].

During the last fifteen years, inhaled corticosteroids were increasingly used for prophylaxis in childhood asthma. The development of inhaled corticosteroids with a high ratio of topical vs systemic potency, now makes possible their use in large doses which are needed to control the most severe forms of the disease, in order to avoid long term oral corticosteroid treatment for these patients. The efficacy of inhaled corticosteroids depends on an optimal pulmonary deposition of the drug which is obtained with children by inhaling the drug via a large volume spacer. Beyond their beneficial effects on the clinical condition of the patients and on pulmonary function, inhaled corticosteroids should improve the long term prognosis of asthma, by reducing chronic inflammation in the airways and the associated bronchial hyperreactivity. At usual dosages, inhaled corticosteroids are free of harmful side effects. However, caution and close observation of adrenal function and growth development are required when prescribing inhaled corticosteroids at high dosages for a long period. Nevertheless, inhaled corticosteroids present very few serious side effects compared with those induced by long term oral corticosteroid treatment.

Administration, Inhalation↗

Variation in peak expiratory flow of normal and asymptomatic asthmatic children.

Peak expiratory flow (PEF) variation was measured in 18 healthy children (Group I) aged 9.25 to 13.3 years (mean, 11 years) and in 17 asymptomatic asthmatic children (Group II) aged 8.75 to 14.25 years (mean, 11.9 years) receiving no bronchodilators. PEF was measured four times a day for a period of 10-14 days. There were no differences between Group I and Group II regarding age, height, weight, sex, duration of the study, and overall mean PEF values. Mean daily PEF variation amplitude (difference between the highest and the lowest daily values as a percent of the mean) was significantly higher in Group II than in Group I subjects (15.2 vs. 9.9%), and so was cosinor amplitude (9.6 vs. 5.9%). Significant circadian rhythm in PEF was detected by cosinor analysis in nine subjects of Group I and in eight subjects of Group II. Mean PEF bathyphase calculated by cosinor analysis (trough time in a 24 h scale) was similar in the two groups (0503 h, in Group I and 0434 h in Group II). The results of this study show that the amplitude of circadian variation in PEF tends to be higher in asymptomatic asthmatic children than in normal children, but there is too much overlap to use PEF monitoring to identify an individual asymptomatic asthmatic child. Therefore, diurnal variation of PEF is not suitable for diagnosing mild asthmatics.

Adolescent↗