[Epidemiologic investigation of the pollen allergy to Cupressaceae in a population at risk for atopy]. / Indagine epidemiologica sulla pollinosi da Cupressacee in un campione di popolazione a rischio di atopia.

The so-called emerging allergens have gained particular interest as causes of atopic diseases, and among these the cypress pollen. In fact, several allergens derived from the Cupressaceae family have appeared for the first time in new environments, thus causing unexpected phenomena. From May 2002 to May 2003 we have examined 560 patients who sought medical attention at the Center for allergic diseases in children. The patients came from various towns and villages from Southern Sardinia and all had undergone prick tests for inhaled allergens, irrespective of their complaints. The presenting symptoms were either respiratory (wheezing cough, rhinitis, asthma), cutaneous (eczema, nettle rash, angioedema) or ocular (conjunctivitis). All patients had a prick test for pollens (cypress, olive, wall pellitory, rag weed, composite, mix gross pollen), acari (Dermatophagoides farinae, Dermatophagoides pteronyssimus), dog and cat hair, and fungi (alternaria alternata, aspergillus fumigatus). Thirteen percent of patients (73/547) resulted allergic to cypress pollen, and three of them had a mono-allergy (4,1%). Among these, one suffered bronchospasm, rhinitis and asthma more severe in January-February associated with recurring small eczematous lesions. Another one suffered bronchial asthma during winter months and the last one complained of rhinitis and nasal itching also during winter months.

Partial proximal trisomy 10q syndrome: a new case.

We report a case of partial proximal trisomy of the long arm of chromosome 10 confirmed by fluorescence in situ hibridization (FISH) performed with whole chromosome 10 specific painting and specific yac clones. The phenotypic findings, compared to those found in other published cases with the same karyotype, support the recognition of a distinctive partial proximal trisomy 10q syndrome (10q11-->q22).

The growth hormone response to hexarelin in patients with Prader-Willi syndrome.

Hexarelin (Hex) is a synthetic hexapeptide with potent GH-releasing activity in both animals and men. Aim of this study was to evaluate the GH response to a maximal dose of Hex and GH-releasing hormone (GHRH) in a group of patients with Prader-Willi syndrome (PWS). Seven patients (4 boys and 3 girls, age 2.4-14.2 yr) with PWS, 10 prepubertal obese children (7 boys and 3 girls, age 7.5-12.0 yr), and 24 prepubertal short normal children (11 boys and 13 girls, age 5.9-13 yr) with body weight within +/- 10% of their ideal weight were studied. All subjects were tested on two occasions with GHRH 1-29 at the dose of 1 microgram/Kg i.v., and with Hex at the dose of 2 micrograms/Kg i.v. In the PWS patients the GH response to GHRH (peak = 6.4 +/- 2.0 micrograms/l, p < 0.0001; AUC = 248 +/- 70 micrograms min/l, p < 0.0001) was significantly lower than that observed in the short normal children and similar to that observed in the obese children. In the PWS children the GH response to Hex (peak = 7.5 +/- 1.6 micrograms/l; AUC = 309 +/- 53) was similar to that observed after GHRH and significantly lower than that observed in the obese children (p < 0.05). The results of this study show that PWS patients have a blunted GH response to the administration of a maximal dose of Hex. Whether these findings reflect a more severe pituitary GH deficiency in PWS than in obese children or a deranged hypothalamic regulation of GH secretion need further investigation.

Growth hormone binding protein activity in obese children.

We evaluated growth hormone binding protein (GHBP) activity in a group of obese children (12 boys and 12 girls, age 3.1-14.7 years, BMI 21.1-33.3, 11 prepubertal and 13 early pubertal) and in 26 age-matched normal weight children (14 boys and 12 girls, age 2.1-16.0 years, BMI 14.2-21.4, 18 prepubertal and 8 early pubertal). All children were of normal stature. GHBP activity was significantly higher in the obese (39.1 +/- 1.1%) than in the control children (28.3 +/- 1.0%, p < 0.0001). Mean serum GHBP was not different between boys and girls or between prepubertal and pubertal subjects. A positive correlation was found between BMI and GHBP levels only in the normal weight children (r = 0.425, p < 0.05). Baseline insulin concentrations in the obese children were 97.6 +/- 7.9 pmol/l (normal values, 45.0 +/- 18.6 pmol/l), and the mean insulin AUC following OGTT in the obese was 811.3 +/- 160.7 pmol/l (normal values, 373.1 +/- 150.1 pmol/l). Serum GHBP activity in the obese was not correlated with baseline serum insulin concentrations or with the insulin AUC following OGTT. In conclusion, we found that obese children have elevated GHBP activity, and speculate that this phenomenon may serve to compensate for their reduced GH secretion and accelerated GH clearance.

Acute administration of hexarelin stimulates GH secretion during day and night in normal men.

OBJECTIVE: Hexarelin is a synthetic hexapeptide with potent GH-releasing activity in both animals and men. The aim of this study was to investigate the effect of a bolus injection of hexarelin given in the morning during wakefulness and during nocturnal sleep in a group of normal adult men. DESIGN AND SUBJECTS: Eight normal men, aged 21-33 years, of normal height and within 10% of ideal body weight were studied. All subjects received in random order saline or hexarelin (2 micrograms/kg) in the morning between 0800 and 0900 h after they had fasted overnight. The same experiments were performed during nocturnal sleep in the same subjects. Saline or hexarelin were injected within 30 minutes after the onset of sleep between 2300 and 2400 h. Sleep was recorded by visual inspection. MEASUREMENTS: In all four test sessions blood samples were taken 30, 15 minutes and immediately before the injection of saline or hexarelin and then every 15 minutes for 2 hours. GH was measured by an immunoradiometric assay. All values are expressed as peak GH levels or as area under the curve (AUC) calculated by trapezoidal integration. RESULTS: Mean peak GH concentrations after hexarelin during the morning (58.2 +/- 4.7 micrograms/l) (GH micrograms/l l x 2 = mU/l) were not different from those observed during sleep (61.2 +/- 4.3 micrograms/l). The rate of disappearance of GH from plasma was slower during sleep (t1/2 = 64.9 +/- 14.8 min) than during morning hours (t1/2 = 24.9 +/- 1.4 min, P < 0.01). Mean AUC responses to hexarelin during sleep (1466 +/- 145 micrograms.min/l) were significantly higher than during morning hours (903 +/- 94 micrograms.min/l, P < 0.001). CONCLUSIONS: These results show that GH responsiveness to a growth hormone releasing peptide is preserved during the night. This could be exploited for diagnostic and/or therapeutic purposes.

Growth hormone (GH) response to GH-releasing hormone in short children: lack of correlation with endogenous nocturnal GH secretion.

The growth hormone (GH) response to iv administration of GH-releasing hormone (GHRH, 0.3 microgram/Kg) was evaluated in 21 short children (13 boys and 8 girls, age 6.7-13.8 yr). Fourteen had familial short stature and/or constitutional growth delay, one had coeliac disease, and 6 were ultimately diagnosed as non-classical GH deficiency or neurosecretory dysfunction on the basis of subnormal integrated spontaneous GH concentrations (ICGH). The response was compared with 12-h spontaneous GH secretion measured every 30 min from 20:00 to 08:00. Mean ICGH ranged from 2.0-17.7 micrograms/l, with a maximum nocturnal GH peak ranging from 5.4-74 micrograms/l. The maximum GH peak after GHRH ranged from 9.4-50 micrograms/l, and the area under the curve (AUC) from 406-3012 micrograms.min/l. No correlation was found between the maximum GH peak and the AUC after GHRH and the maximum overnight GH peak, the ICGH and the overnight AUC. This study confirms that the GH response to GHRH is highly variable among short children with a wide range of spontaneous GH secretion, and that this response is not correlated with the spontaneous ability to secrete GH.

The growth hormone response to hexarelin in children: reproducibility and effect of sex steroids.

We studied the variability of the GH response to the synthetic hexapeptide hexarelin (Hex) and the effect of sex steroids on the GH-releasing effect of Hex in a group of prepubertal short normal children. Twenty-five children were tested on two occasions 3-7 days apart with 2 micrograms/kg, i.v., Hex. The GH response to Hex was reevaluated after testosterone (T) administration in 10 boys, after ethinyl estradiol (EE) administration in 15 children (5 boys and 10 girls), and after oxandrolone (Ox) administration in 8 boys. In the 25 children tested twice, the mean GH peak and mean area under the curve after the first and second tests were similar. The mean (+/- SD) coefficients of variation of the GH peak and area under the curve responses to Hex was 22.7 +/- 21.0% and 24.0 +/- 20.7%, respectively. Priming with T and EE resulted in an increased GH response to Hex [41.8 +/- 21.0 before vs. 71.1 +/- 28.3 after T (P < 0.001); 43.0 +/- 14.5 before vs. 60.0 +/- 20.0 after EE (P < 0.005)], whereas Ox administration had no effect on the Hex-induced GH release. These data confirm that Hex is a potent stimulus for GH secretion in children with a limited intraindividual variability. In addition, we have shown that both T and EE, but not Ox, significantly augment the GH-releasing effect of Hex. Our data suggest that the sex steroid-induced increase in the GH response to Hex is mediated by estrogens.

The GH/IGF-I axis in puberty.

Puberty, either spontaneous, precocious or pharmacologically induced has profound effects on the physiology of the GH/IGF-I axis. Both spontaneous and stimulated GH secretion increase with puberty. The increase in spontaneous GH secretion is the result of increased GH pulse amplitude rather than frequency, and is probably an oestrogen-dependent effect. Parallel to the increase in GH secretion at puberty, circulating IGF-I and IGF binding protein-3 also increase. The pubertal increase in IGF-I correlates with stages of puberty as well as sex steroid levels. Circulating immunoreactive GHRH also increases with puberty, while circulating GH-binding protein levels are not affected by sexual maturation. Several data suggest an important role for the GH/IGF-I axis in the pubertal growth spurt. More recent data, however, have provided evidence of an important role for gonadal hormones in promoting adolescent growth independent of GH.

The effect of hexarelin on growth hormone (GH) secretion in patients with GH deficiency.

Hexarelin (Hex) is a new synthetic hexapeptide with potent GH-releasing activity in both animals and men. We evaluated the GH response to maximal doses of Hex (2 micrograms/kg, iv) and GHRH-(1-29) (1 microgram/kg, iv) in 15 children (11 boys and 4 girls, aged 6.0-17.3 yr) and 4 adults (3 men and 1 woman, aged 20.2-30 yr) with GH deficiency (GHD). GHD was idiopathic in 8 patients and associated with pituitary stalk interruption syndrome in 8, with a pituitary cyst in 2, and with empty sella syndrome in 1. In 11 patients, GHD was isolated, whereas in 8, it was associated with other pituitary hormone deficiencies. Forty-five short normal children (24 boys and 21 girls, aged 5.9-14 yr) served as controls. In patients with idiopathic GHD, the GH response to Hex was similar to that observed in short normal children, and it was significantly higher than the response to GHRH. In the patients with GHD associated with anatomical abnormalities, the GH responses to GHRH varied from normal to absent. Among these subjects, only 1 patient with a pituitary cyst had a sizable GH response to Hex, whereas in all others, the GH response to Hex was absent or blunted compared with those in the short normal children and the patients with idiopathic GHD. In all patients except those with associated ACTH deficiency, Hex administration caused a slight, but significant, increase in cortisol concentrations. This study shows that Hex stimulates GH secretion in patients with idiopathic GHD. The inability of Hex to stimulate GH secretion in patients with hypothalamic-pituitary disconnection strongly supports the concept that in humans, the GH-releasing effect of GH-releasing peptides is mediated by the hypothalamus.

Growth hormone response to oral clonidine test in normal and short children.

We evaluated the growth hormone (GH) response to an acute clonidine test (0.15 mg/m2 po) in 30 normal prepubertal children (stature between the 3rd and 97th centile), in 29 short children (stature < 3rd centile for age) with height velocity (HV) > 10th centile and in 20 short children with HV < 10th centile. The three groups had comparable chronological ages. After clonidine administration mean peak GH levels were similar in the three groups (19.4 +/- 9.8, 17.7 +/- 8.8 and 14.6 +/- 8.9 micrograms/l, mean +/- SD, respectively). By choosing 10 micrograms/l as the limit for a normal response we found that stimulated GH levels had a sensitivity of 50% and a specificity of 83% in identifying children with suspected GHD (short children with subnormal HV). The diagnostic accuracy was almost superimposable, for cut-off values of 10 and 12 micrograms/l. Eight of the 10 children with subnormal HV and a GH peak < 10 micrograms/l had a GH peak < 10 micrograms/l also after a second stimulation test. Six of the 29 short children with normal HV had a GH peak < 10 micrograms/l. Only one of them had a GH peak < 10 micrograms/l after a second stimulation test. Five of the normal children had peak GH levels < 10 micrograms/l. These results indicate that HV is a useful variable to predict the GH response to an acute GH stimulus, since the great majority of children with a normal growth rate had a normal GH response to at least one stimulation test.

Secretion of growth hormone releasing hormone in obese children.

We have evaluated baseline and l-dopa-stimulated peripheral growth hormone releasing hormone (pGHRH) secretion in 6 obese pre-pubertal children and in 7 age-matched controls. Baseline pGHRH levels were no different between obese (36.6 +/- 9.8 pg/ml, mean +/- SE) and control children (40.6 +/- 10.1 pg/ml). Administration of l-dopa (500 mg po) caused a significant increase of pGHRH levels in both the obese (65.3 +/- 19.8 pg/ml, p less than 0.05) and the control children (84.1 +/- 10.0 pg/ml, p less than 0.003). Mean peak pGHRH levels after l-dopa were not significantly different between the two groups, whereas mean peak GH levels were significantly lower (p less than 0.05) in the obese (7.9 +/- 1.9 ng/ml) than in the control children (20.5 +/- 4.9 ng/ml). We conclude that despite reduced GH secretion, obese children have normal baseline and l-dopa stimulated pGHRH levels.

The growth hormone response to pyridostigmine plus growth hormone releasing hormone is not influenced by pubertal maturation.

We have evaluated the effect of pubertal maturation on the GH response to growth hormone releasing hormone (GHRH), pyridostigmine (PD) and the combined administration of PD + GHRH in a group of short normal children. Fifteen were prepubertal (13 boys and 2 girls, age 5.0 - 12.5 yr), 10 were early pubertal (8 boys and 2 girls, age 11.5 - 16.9 yr in Tanner stage 2-3 of pubertal maturation), and 6 were late pubertal (6 boys and 2 girls, age 13.6 - 17.1 yr in Tanner stage 4-5 of pubertal maturation). All subjects were tested on three occasions with GHRH 1-29 (1 microgram/Kg iv), PD (60 mg po) and PD + GHRH (60 mg PD administered orally 60 min before GHRH). Peak GH levels after GHRH, PD, and PD + GHRH in the prepubertal children (16.0 +/- 2.8, 8.1 +/- 1.3 and 51.1 +/- 5.5 ng/ml, mean +/- SE, respectively) were not different from those observed in the early pubertal (18.4 +/- 2.1, 9.1 +/- 1.9 and 41.2 +/- 5.6 ng/ml, respectively) and in the late pubertal group (14.9 +/- 2.3, 13.1 +/- 2.4 and 42.6 +/- 2.9 ng/ml, respectively). Evaluation of the area under the curve (AUC) also showed no difference in the GH response to GHRH, PD and PD + GHRH between the three groups studied. These results confirm that the combination PD + GHRH is a powerful test to study the GH secretory capacity of the pituitary, and show that pubertal maturation has no effect on the GH response to this test.

Reduced growth hormone response to growth hormone-releasing hormone in children with simple obesity: evidence for somatomedin-C mediated inhibition.

We have evaluated the plasma GH response to a single injection of 1 microgram/kg of GH-releasing hormone (GHRH)-40 in 15 obese children and 15 age-matched control children. Most of the obese children showed a subnormal plasma GH response to GHRH and the mean plasma GH integrated area (IC-GH) following stimulation was significantly smaller in obese than control children. Plasma somatomedin-C (SM-C) levels were significantly higher in obese than control children, and were negatively correlated with the peak plasma GH levels (r = -0.616, P less than 0.01) and the IC-GH (r = -0.554, P less than 0.02) after GHRH. Non-esterified fatty acids (NEFA) and fasting plasma insulin levels were also elevated in obese children, but did not correlate with the extent of plasma GH response to GHRH. These data confirm previous observations on the refractoriness of obese children to release GH after GHRH, and imply that it may be due to the feedback inhibition operated by the elevated plasma levels of SM-C.

Microfilter paper method for antipyrine determination in whole blood by high pressure liquid chromatography.

A method for measuring antipyrine in whole blood collected on filter paper is described. A 6.2-mm diameter disc (1/4 in) is punched out, eluted with distilled water, and then extracted with 5 ml of dichloromethane/pentane (50:50, vol/vol). After reconstitution of the dried residue, reverse-phase high pressure liquid chromatography is used to quantitate antipyrine using an internal standard. A mixture of 15% acetonitrile in 0.006 M phosphate buffer pH 7.2 was used as the mobile phase. Chromatography was carried out under isocratic conditions for 15 min. The retention time of antipyrine was 3.6 min. Intra- and interassay coefficients of variation were 3.1% and 7.2%, respectively. The limit of sensitivity was 6 ng/injection. The amount of blood in a 6.2-mm filter paper disc was calculated to be 8.4 +/- 0.8 (SD) microliter. Antipyrine half-lives, apparent volumes of distribution, and metabolic clearance rates measured from the filter paper concentrations or directly from plasma were virtually identical. Antipyrine was stable on filter paper for less than or equal to 6 weeks at room temperature. The method reported is convenient; requires a small amount of blood, which can be easily obtained by fingerstick; and readily permits the measurement of antipyrine clearance in the pediatric as well as adult populations.

Adrenal androgens in obese boys before and after weight loss.

The adrenal steroid secretion was studied in 6 prepubertal obese boys and 6 obese boys at the first stage of sexual maturation according to Tanner. Twelve normal boys, closely matched for age and stage of sexual maturation, were also studied as controls. Pregnenolone and dehydroepiandrosterone plasma levels were found to be significantly (P less than 0.001) higher in both groups when compared with normal boys. All the values, apart from pregnenolone in the prepubertal group, returned to normal after weight loss. Progesterone was found significantly increased (P less than 0.001) in both groups and normal after weight loss. 17-OH-progesterone plasma levels showed no significant difference between the obese and control groups. Androstenedione was increased in the prepubertal group before and normal after weight loss; no significant difference was found in the other group. Testosterone and estradiol showed normal values in the two groups both before and after weight loss. Cortisol showed a similar pattern. It can be concluded that an increased cortico-adrenal activity is present in obese boys as already reported in obese girls. This finding could explain the precocious adrenarche which often occurs in these patients. The increased adrenal androgen secretion might be due to an increased cortico adrenal stimulating hormone secretion or to an enhanced adrenal sensitivity to this hypothetical hormone.

Sexual maturation and adrenal function in girls with thalassemia.

Adrenal steroid production was evaluated in 12 thalassemic girls aged between 18 and 22 years and at stage P1 of sexual maturation according to Tanner. The values found in these patients were compared with those in 12 normal girls of the same age at stage P4-5 of sexual maturation. Pregnelone, dehydroepiandrosterone, dehydroepiandosterone sulfate, progesterone, 17-OH-P, androstenedione, testosterone, dihydrotestosterone and estradiol were found to be significantly reduced (p less than 0.001) in the thalassemic group, while cortisol levels showed a slight but not statistically significant reduction. Plasma ferritin levels were greatly increased and showed a highly significant (p less than 0.001) correlation coefficient when plotted against each hormone. The present results suggest that the impaired adrenal function plays an important role in determining the delayed sexual maturation almost always present in the thalassemic patients and that this disorder may be due to iron overload.

Adrenal and testicular function in boys affected by thalassemia.

The adrenal androgen secretion and testicular function were studied in 6 thalassemic boys aged between 16 and 20 years. Six normal boys of the same age and 6 at the same pubertal stage (P1 according to Tanner) were also studied as controls. Plasma testosterone levels were found significantly lower (p less than 0.001) in the thalassemic boys (0.8 +/- 0.1 ng/ml) than in healthy boys of the same age (3.4 +/- 1.01 ng/ml), but within the range of the healthy boys at the same pubertal stage (0.69 +/- 0.1 ng/ml). DHA-S, a marker of adrenal maturation, showed a similar pattern. The hCG test showed a significant (p less than 0.001) testosterone response in all 3 groups. The response of thalassemic boys (1.5 +/- 0.18 ng/ml) was similar to that of normal boys at stage P1 (1.8 +/- 0.31 ng/ml), but significantly lower (p less than 0.001) than the group of normal boys of the same age (12.5 +/- 3.2 ng/ml). The impaired adrenal and testicular activity is probably due to iron deposits in the endocrine glands.

Effect of short dexamethasone suppression on plasma steroids in prepubertal and pubertal girls.

In 40 girls aged from 2 to 14 years, subdivided into groups according to age and pubertal development, and in 6 adult female volunteers, plasma cortisol (F), pregnenolone (delta 5), dehydroepiandrosterone (DHA) progesterone (P), 17-hydroxyprogesterone (17P), androstenedione (A), testosterone (T) and estradiol (E2) were measured before and after short dexamethasone (DXM) suppression. The results confirmed the capacity of DXM to inhibit plasma steroids in all age groups, except T in 2-9 year old and P1 Tanner's stage girls. The percentage suppression of each given steroid was constant over the age groups from 6-9 years to P4-5 Tanner's stage, while lower suppression was found in 17P, P and DHA in 2-5 year old girls and in 17P, DHA and E2 in adult women. These results emphasize the fundamental role of ACTH as the overall stimulating factor of adrenal steroidogenesis but do not negate the possibility of another factor responsible for the development of the adrenal androgen secreting cells throughout prepuberty and puberty.

Adrenal and gonadal steroids and pituitary response to LHRH in girls. I. Delayed puberty.

Plasma levels of luteinizing hormone (LH), follicle stimulating hormone (FSH), dehydroepiandrosterone (DHA), dehydroepiandrosterone-sulphate (DHA-S), 17-hydroxyprogesterone (17P), androstenedione (A), testosterone (T), dihydrotestosterone (DHT) and estradiol (E2) were measured in basal conditions in eleven young women from 16 to 25 years of age characterized by delayed puberty. The gonadotropin response to LHRH (50 microgram iv) was also tested in these cases. The results, as far as gonadotropins and E2 are concerned, indicate that delayed pubertyin girls is a heterogeneous disorder: an impairment in the negative feedback between E2 and FSH coexists with a reduced ovarian response to endogenous gonadotropins. All cases showed evidence of a more or less pronounced delayed adrenarche, which was demonstrated by the markedly reduced levels of DHA-S and DHA (with the exception of this latter steroid in two cases with idiopathic hirsutism). Furthermore, the very low plasma progesterone (P) levels in all cases suggest the existence of impaired delta 5 - delta 4 isomerase activity in the adrenal cells. Despite the low levels of A and T, DHT is within the upper limits of the normal range in all cases.