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L Bosio

Publications and source records attributed to L Bosio.

At least 19 recordsLinked to original sources
PubMed2003

Hypogonadism and pubertal development in Prader-Willi syndrome.

UNLABELLED: Genital abnormalities and disorders of pubertal development such as hypogonadism are common in Prader-Willi Syndrome (PWS). Depending on age, PWS patients present genital hypoplasia and delayed or incomplete gonadal maturation. Nevertheless, only a few evaluations have been made of these findings in this syndrome; in the cases previously reported the diagnosis of PWS has often been based only on clinical criteria and not confirmed by genetic analysis. In this paper we describe both external genital findings and spontaneous pubertal development in 84 patients aged from 2.1 to 35.4 (42 males, 42 females) affected by PWS. Diagnosis was made using the Holm and Cassidy criteria and was confirmed by genetic analysis (methylation test and/or FISH). We evaluated the presence of cryptorchidism, scrotal development, length of penis and volume of testis in males and outlook of labia minora and/or clitoris, age of menarche and features of menses (when present) in females; in both sexes we also evaluated the onset of puberty. All recruited males showed cryptorchidism, which was bilateral in 36 out of 42 patients (86%); 38 patients (90%) underwent orchidopexy. Small testes and scrotal hypoplasia were present in 76% and 69% of cases, respectively. In 76% of females, hypoplasia or absence of labia minora and/or clitoris was described. Spontaneous menarche occurred only in 14/32 cases (44%) over the age of 15 years, but menstrual cycles were often a periodical vaginal spotting. Primary amenorrhea was diagnosed in 56% of cases. Isolated premature pubarche was present in six males and in six females (14% of cases) while one male and two females were affected by precocious puberty (3.6%). CONCLUSION: Hypogonadism represents a common clinical feature in PWS, confirming the importance of such a major diagnostic criterion. Cryptorchidism was consistently present in all our cases. Patients with PWS commonly fail to spontaneously complete puberty, although some patients may have early pubarche or, more rarely, precocious puberty. In older subjects, hormonal replacement therapy is not always necessary and it must be reserved for selected patients.

Adolescent↗
PubMed2003

Neonatal hypotonia: don't forget the Prader-Willi syndrome.

UNLABELLED: During the neonatal period the diagnosis of the Prader-Willi syndrome (PWS) is difficult because the syndrome is expressed mainly by severe hypotonia at this age and the typical clinical features of later life are not yet present. AIM: To identify all the PWS clinical markers in severe hypotonic newborns, which could facilitate an early diagnosis of the syndrome. METHODS: Twenty-one PWS newborns (14 males and 7 females) with severe hypotonia at birth were evaluated. Paediatricians skilled in syndromology carried out a careful clinical examination. Fluorescent in situ hybridization (FISH) analysis and/or a methylation test was used to confirm the PWS clinical diagnosis. RESULTS: The clinical diagnosis of PWS was reached at a mean age of 7.4 mo with genetic confirmation at 11 mo of life. In 12 newborns at least 3 craniofacial features were present (57%), suggesting the diagnosis of PWS. Two craniofacial dysmorphic characteristics were described in 6 newborns and only 1 in 3 cases. Cryptorchidism was monolateral in 6 and bilateral in 7 patients; in one newborn both testes were in scrotum. A micropenis was described in one patient and hypoplasia of the labia minora was reported in two females. CONCLUSIONS: Diagnosis by means of dysmorphologic evaluation is difficult in the neonatal period. The presence of severe hypotonia should always induce neonatologists to perform specific genetic tests in order to obtain an early diagnosis of PWS.

Adult↗
PubMed2000

GH/IGF-I axis in Prader-Willi syndrome: evaluation of IGF-I levels and of the somatotroph responsiveness to various provocative stimuli. Genetic Obesity Study Group of Italian Society of Pediatric Endocrinology and Diabetology.

Basal IGF-I levels and the GH response to at least two among provocative stimuli such as clonidine (CLO, Catapresan, 150 mcg/m2 p.o.), GHRH (1 mcg/kg i.v.)+arginine (ARG, 0.5 g/kg i.v. infusion during 30 min) and GHRH+pyridostigmine (PD, Mestinon cpr 60 mg p.o.) have been evaluated in 43 children with Prader-Willi syndrome (PWS, 17 males and 26 females, age 3-22 yr, 7 normal weight and 36 obese PWS), in 25 normal short children (NC, 17 males and 8 females, 7.7-18.5 yr) and in 24 children with simple obesity (OB, 14 males, 10 females, 7.7-21.5 yr). Both normal weight and obese PWS had mean IGF-I levels lower than those recorded in NC (p<0.001) and OB (p<0.001). The GH responses to GHRH+ARG and GHRH+PD in NC were similar and higher than that to CLO (p<0.001). In PWS the GH response to GHRH+ARG was higher than that to GHRH+PD (p<0.001) which, in turn, was higher than that to CLO (p<0.001); these responses in PWS were lower than those in normal children (p<0.02) and similar to those in OB. In normal weight PWS the GH responses to GHRH+ARG and to GHRH+PD were similar and higher than to CLO (p<0.05); however, each provocative stimulus elicited a GH rise lower than that in NC (p<0.05). In obese PWS as well as in OB the GH response to GHRH+ARG was higher than that to GHRH+PD (p<0.02) which, in turn, was higher than that to CLO (p<0.001); all GH responses in obese PWS and OB were lower than those in NC (p<0.001) but similar to those in normal weight PWS. In conclusion, patients with PWS show clear reduction of IGF-I levels as well as of the somatotroph responsiveness to provocative stimuli independently of body weight excess. These results strengthen the hypothesis that PWS syndrome is frequently connotated by GH insufficiency.

Adolescent↗
PubMed1999

[Prader-Willi syndrome].

Prader-Willi syndrome (PWS) is the most frequent cause of secondary obesity, characterized by neonatal hypotonia, dysmorphic facies, acromicria, hypogonadism, stunted growth, obesity, behavioural disturbances and cognitive impairment. Clinical diagnosis is confirmed by alteration of imprinted genes on the proximal long arm of chromosome 15 (15q11-13) for deletion, translocation, uniparental disomy for maternal chromosome 15 or imprinting center defect. Methylation test is the most reliable test for diagnosis. This issue explains diagnostic tests, clinical, metabolic, endocrinological features, and the most frequent complications observed in this syndrome. Precocious diagnosis and multidisciplinary approach allow in these patients to prevent the severe obesity and linked complications.

Diagnosis, Differential↗
PubMed1999

Body composition during GH treatment in Prader-Labhardt-Willi syndrome.

Prader-Labhardt-Willi syndrome (PLWS) is a model to study GH secretion, body composition and consequences of GH therapy. Twenty-seven patients were studied by dual-energy X-ray absorptiometry (DXA) and were each compared to two age- and sex-matched controls (obese and normal weight). Fat mass (FM) was significantly greater in PLWS than in patients with simple obesity; lean body mass (LM) and bone mineral content (BMC) were significantly lower compared to both controls. The peculiar body composition of PLWS patients seems to be similar to that found in GH deficiency. In six PLWS children treated with GH, LM increased after 6 months (p<0.02) up to 12 months (p<0.03); FM decreased in 5/6 patients. Obese adult PLWS patients treated with GH for 6 months showed a reduction in adiposity; LM increased significantly only in the leg compartment. Abdominal CT scan did not show a significant reduction of intrabdominal fat area. In conclusion, GH therapy might improve final stature and exert a positive influence on body composition in patients with PLWS.

Adipose Tissue↗
PubMed1998

Prader-Willi syndrome: relationship of adiposity to plasma leptin levels.

OBJECTIVE: Prader-Willi syndrome (PWS) is an autosomal dominant disorder involving the proximal long arm of chromosome 15, in which obesity is common. However, there is limited information on the underlying physiological mechanisms promoting obesity in this population. We tested whether there was a significant positive association between leptin and total body fat (TBF) in subjects with PWS, and whether this association was stronger among subjects with than without PWS. RESEARCH METHODS AND PROCEDURES: We studied 21 PWS patients and 64 non-PWS controls on whom we measured serum leptin, total body fat, glucose, insulin, and resting energy expenditure. We tested whether the slope of the regression line between leptin and TBF (in kg), measured by dual energy X-ray absorptiometry, was the same for PWS patients and non-PWS controls. RESULTS: Regression analyses indicated that the leptin-TBF association was significantly stronger among PWS patients. In contrast, the slope of the leptin-body mass index association did not significantly differ between PWS patients and non-PWS controls. None of the other outcome variables showed associations with leptin. DISCUSSION: Results suggest that the role of leptin in promoting obesity may be greater among subjects with PWS than among non-PWS controls.

Absorptiometry, Photon↗
PubMed1998

A structural study of beta-casein adsorbed layers at the air-water interface using X-ray and neutron reflectivity.

New details on the structure of beta-casein adsorbed layers, at the air-water interface, have been obtained using X-ray and neutron reflectivity. The experimental data are fitted well by a power law model and the results discussed in terms of the distribution of amino-acid sequences between trains, loops and tails. This distribution seems to be consistent with statistical theories established for flexible polymers. The trains are present in close proximity to the surface as a dense layer 8-9 A thick. At low surface coverage, the tail effect is negligible and the adsorbed layer is composed of nearly 60% amino-acid sequences in trains and the remaining in loops. When the bulk concentration is increased, a substantial part of the amino-acid residues has to be accommodated in loops and long tails; the adsorbed layer becomes more extended (80-100 A). A striking feature is observed for a high bulk concentration (10(-1) wt.%): trains are forced to eject out of the interface.

Adsorption↗
PubMed1997

Peculiar body composition in patients with Prader-Labhart-Willi syndrome.

Prader-Labhart-Willi syndrome (PWS)-characterized by severe obesity, short stature, hypogonadism, and muscle hypotonia-appears to be an interesting model for body-composition abnormalities. Twenty-seven PWS patients (15 males and 12 females) aged 6-22 y underwent total-body analysis by dual-energy X-ray photon absorptiometry (DXA). For each PWS patient two age- and sex-matched control subjects were studied: one obese subject with a relative body weight (RBW > 120%) and body mass index (BMI) similar to that of the patient and one normal-weight subject (RBW < 120%). Percentage body fat was significantly greater in PWS patients than in obese subjects (47.4 +/- 7.2% compared with 41.9 +/- 9.9%, P < 0.0001) and the same difference was evident for arms and legs but not for the trunk. Lean mass was significantly lower in PWS patients (26.4 +/- 8.2 kg) than in normal-weight subjects (32.9 +/- 10.2 kg) and even more so than in obese subjects (40.3 +/- 13.2 kg) (P < 0.0001). The most affected regions were limbs; thus, the ratio of lean mass in the trunk to that in the limbs was significantly higher in PWS patients (1.19 +/- 0.15) than in obese (1.07 +/- 0.13) and normal-weight (1.07 +/- 0.09) subjects (P < 0.002). The ratio of fat mass to lean mass was significantly higher in PWS patients than in obese subjects (0.90 +/- 0.32 and 0.74 +/- 0.27, P < 0.05). Bone mineral content (BMC) was significantly lower in PWS patients (1503 +/- 46 g) than in normal-weight (1876 +/- 677 g) and obese (2322 +/- 773 g) subjects (P < 0.0001); this difference was most pronounced in the limb region. Bone mineral density (BMD) in PWS patients (0.993 +/- 0.116 g/cm2) did not differ significantly from that of normal-weight subjects (1.033 +/- 0.147 g/cm2) but was significantly lower than that of obese subjects (1.154 +/- 0.139 g/cm2). The influence of age on body composition was assessed by comparing two age subgroups (< 12 y, n = 10; and > or = 12 y, n = 17). The older PWS patients had higher adiposity, lower BMC, and dramatically lower BMD. Also, the lean mass deficit increased with age so that the ratio of fat mass to lean mass was close to 1. In conclusion, PWS patients showed a peculiar body composition, to some extent similar to that found in subjects deficient in growth hormone or even to sedentary and elderly people. These results suggest the importance of an accurate analysis of body composition in PWS patients.

Adipose Tissue↗
PubMed1996

Impairment of growth hormone responsiveness to growth hormone releasing hormone and pyridostigmine in patients affected by Prader-Labhardt-Willi syndrome.

In order to evaluate the impairment of GH response in patients affected by Prader-Labhardt-Willi (PLW) syndrome, in 18 patients we studied GH response to clonidine and to GHRH + pyridostigmine, a cholinergic drug which enhances GHRH induced GH responsiveness in obese patients. After clonidine GH response was abnormal in 14/18 subjects (mean GH peak: 4.1 +/- 1.3 micrograms/l; area under curve: 208.1 +/- 74.2 micrograms/l.h) while all but 5 patients showed an inadequate GH response to GHRH + pyridostigmine (mean GH peak: 13.4 +/- 2.5 micrograms/l; area under curve: 903.4 +/- 171.0 micrograms/l.h). However, in the three patients with low adiposity index, GH response to GHRH + pyridostigmine was significantly higher than that observed in fatter subjects. In addition, GH response to GHRH + pyridostigmine was negatively correlated to age and adiposity index. In conclusion, our data are consistent with the hypothesis of the existence of a complex derangement of GH neuroendocrine regulation in these subjects.

Adolescent↗
PubMed1992

[Changes in dynamic respiratory volumes in obese children and adolescents related to weight loss and sex].

Obesity is associated with various alterations in lung function in adults. These alterations appear to be proportional to the degree of EP and the beneficial effect of weight loss on respiratory function has been reported. Therefore, in 35 children and adolescents affected by essential obesity of medium-severe degree, we have evaluated the following parameters: FVC (forced vital capacity), PEF (peak expiratory flow), FEV1 (forced expiratory volume), FEV75, FEV50, FEV25, before and after six months of dieting. Twelve subjects (34%) showed at least a pathologic value of PEF and/or FEV50 before dieting. All the female patients normalized their parameters after six months of dieting, whilst 5 out of 7 males still showed pathologic respiratory indexes, although a similar weight loss was obtained in the two groups of patients. Our study enhances the presence of respiratory functions derangements in a significant percentage of children with medium-severe degree of obesity. A careful monitoring of these subjects is therefore necessary, in order to prevent further progression of the lung function damage. After dieting the pulmonary function improved in female patients only, suggesting that factors other than the EP are involved in the pathogenesis of the respiratory alterations.

Adolescent↗
PubMed1991

[The usefulness of measuring fructosamine in the cord blood of the newborn infants of diabetic mothers].

The aim of our study was to evaluate the usefulness of fructosamine measurement (Fram) in cord blood as an index of glucose metabolism in the last week of pregnancy in infants of diabetic mothers. In newborns and their respective mothers Fram values were surprisingly greater in N than in IDM and IGDM and neonatal and maternal values appeared to be strictly related. While intrauterine growth was associated with metabolic control indexes of 2nd and 3rd trimester gestation. Fram value appeared positively correlated to cord insulin. In conclusion Fram level appears as a good index of glucose metabolic control of the last week of pregnancy and it is associated to cord insulin level and to neonatal hypoglycemia.

Blood Glucose↗
PubMed1990

Growth acceleration and final height after treatment for delayed diagnosis of celiac disease.

The only presenting clinical feature of diagnosing celiac disease (CD) late may be short stature. At the start of treatment with a gluten-free diet (GFD), celiac children show an accelerated growth rate. The real duration of catch-up growth and influence of diet on the final stature has not yet been defined. In order to evaluate the effect of a GFD on growth parameters, 24 children diagnosed late with CD were studied at our center. During the period of diagnosis, weight, height standard deviation score (HSDS), weight and height velocities (WV and HV), bone age (BA), and pubertal stage were recorded. Predicted height (PH) according to the Tanner method, parental height, and target height (TH) were also evaluated at diagnosis. All patients initially presented because of short stature or retarded growth (100% of patients with height less than 5th percentile). Patients showed an increased HV and WV during the first 3 years on a GFD, with maximum growth velocity occurring during the first year, but the catch-up growth was incomplete over 3 years (mean HSDS +/- SD, -1.77 +/- 0.6). Puberty began in all patients at a normal age. The 12 patients who completed pubertal development reached their target height, whatever the duration of the GFD. The final height (between the 1st and 25th percentile) seemed influenced mainly by familial characteristics; height was below the 3rd percentile in 31% of parents examined.

Adolescent↗
PubMedDate not supplied

GH secretion in Prader-Labhard-Willi syndrome: somatotrope responsiveness to GHRH is enhanced by arginine but not by pyridostigmine.

Low somatotrope responsiveness to secretagogues has been reported in patients affected by Prader-Labhard-Willi Syndrome (PLWS). In normal subjects, GH response to GHRH is known to be greatly potentiated to the same extent by pyridostigmine (PD) or arginine (ARG) which probably act via inhibition of hypothalamic somatostatin release. To clarify somatotrope responsiveness in 7 PLWS patients, we studied GH response to GHRH alone and to GHRH combined with PD or ARG. Eight normal short children were studied as controls (NC). GH response to GHRH in PLWS was lower than in NC (AUC: 615 +/- 205 micrograms/l.h, vs 1271 +/- 333 micrograms/l.h, p < 0.02). In NC, the GHRH-induced GH rise was potentiated to the same extent by PD or ARG. In contrast, in PLWS PD failed to increase the GH response to GHRH (AUC: 615 +/- 205 micrograms/l.h vs 621 +/- 176 micrograms/l.h, n.s.) which was enhanced by ARG (AUC: 615 +/- 205 micrograms/l.h vs 1633 +/- 425 micrograms/l.h, p < 0.02). However, the GH response to GHRH + ARG in PLWS was lower than in NC. In conclusion, our results demonstrate that in PLWS the low somatotrope responsiveness to GHRH is not enhanced by cholinergic potentiation while it is increased by arginine.

Adolescent↗