Roughening of k-mer-growing interfaces in stationary regimes.

We discuss the steady-state dynamics of interfaces with periodic boundary conditions arising from body-centered solid-on-solid growth models in 1+1 dimensions involving random aggregation of extended particles (dimers, trimers, ...,k-mers). Roughening exponents as well as width and maximal height distributions can be evaluated directly in stationary regimes by mapping the dynamics onto an asymmetric simple exclusion process with k-type of vacancies. Although for k≥2 the dynamics is partitioned into an exponentially large number of sectors of motion, the results obtained in some generic cases strongly suggest a universal scaling behavior closely following that of monomer interfaces.

Bloodstream infections in children with cancer: a multicentre surveillance study of the Italian Association of Paediatric Haematology and Oncology. Supportive Therapy Group-Infectious Diseases Section.

A one-year prospective, multicentre surveillance study on aetiology, main clinical features and outcome of bloodstream infections in children with cancer was conducted in 18 paediatric haematology centres belonging to the Italian Association for Paediatric Haematology and Oncology. A total of 191 bloodstream infections were reported during the study period. Of them, 123 (64%) occurred in neutropenic and 68 (36%) in non-neutropenic patients. Gram-positive cocci caused 45% (85/191) of the episodes, gram-negative rods 41% (78/191), and fungi 9% (18/191). The remaining 5% (10/191) of the episodes were poly-microbial infections. A total of 204 pathogens were isolated (46% gram-positive cocci; 44% gram-negative rods; and 10% fungi). The aetiologic distribution was similar among neutropenic and non-neutropenic patients. A correlation between the infection and the presence of an indwelling central venous catheter was found in 20% (23/114) of the episodes among neutropenic patients and in 55% (23/62) among non-neutropenic patients. Gram-negative micro-organisms were isolated in an unusually high proportion of catheter-related infections (48%). The overall mortality rate from any cause within 30 days from the first positive blood culture was 11%, and was higher among patients who were neutropenic at the onset of the infection than among those who were not neutropenic (15 versus 4%, P = 0.03). In addition, the mortality was significantly higher in recipients of bone marrow transplantation than in patients with acute leukaemia or solid tumour (21, 11 and 6%, respectively) and was also higher in fungaemias and poly-microbial infections (22 and 30%) than in single gram-positive and gram-negative bacteraemias (11 and 6%).

Long-term GnRH-agonist administration revealed a GnRH-independent mechanism stimulating FSH discharge in humans.

The present study evaluated the FSH and LH episodic discharge in different physiopathological conditions undergoing chronic GnRH-agonist administration. Four girls with true precocious puberty and five postmenopausal women were administered GnRH-agonist (3.73 leuprolide acetate every 4 weeks; Takeda Italia, Rome, Italy) for at least 4 months. Plasma LH and FSH secretory profiles were assessed before and under GnRH-agonist administration (after 21 and 120 days). Pulsatility studies were conducted for 4 h in the girls and for 6 h in postmenopausal women, with blood sampling intervals of 10 min. Pubertal and postmenopausal patients showed the distinct episodic co-secretion of LH and FSH before GnRH-agonist administration; this co-secretion disappeared in both groups after 21 and 120 days of treatment. Moreover, while LH concentrations decreased to almost undetectable levels and LH episodic release disappeared, FSH plasma levels were only partially reduced and FSH episodic secretion was detectable in both groups. In conclusion, this study demonstrated that long-term GnRH-agonist administration blocked LH but not FSH episodic release. These data enforce the hypothesis that FSH episodic discharge might be dependent not only on hypothalamic GnRH, but also on a GnRH-independent stimulatory pathway.

Intrinsic secretory characteristics of luteinizing hormone and prolactin episodic release during pubertal development.

The intrinsic characteristics of LH and prolactin (PRL) episodic secretion were evaluated in a group of 18 children (8M and 10F). The children were divided into two groups according to the Tanner stage: Group A (Tanner < or = 1, N = 7, 3M and 4F, 6-10 years of age) and group B (Tanner 2-3, N = 11, 5M and 6F, 9-11 years of age). A pulsatility study of 4 h, sampling every 10 min, was carried out in all children. LH and PRL plasma levels were assayed by IFMA and RIA respectively. LH and PRL secretory episodes were then identified on plasma determinations using the program DETECT. Instantaneous secretory rates (ISR) were then computed for both LH and PRL using the specific algorithm within the DETECT program. Plasma LH levels were different between the two groups of children. Group A children showed undetectable LH plasma levels (below the minimal detectable dose of 0.1 mIU/ml), while group B demonstrated LH plasma levels in the normal range of values for age and sexual development (1.5 +/- 0.3 mIU/ml, mean +/- SEM). LH pulse frequency for group B was 3.2 +/- 0.4 peaks/4 h. No significant differences in mean plasma PRL levels, pulse frequency and pulse amplitude were observed between the two groups of children. Computation of ISR for LH (group B only) and PRL (both groups) identified the intrinsic episodic characteristics of the two hormones. No significant differences in LH and PRL pulse frequencies were observed when comparing the results estimated on ISR with those estimated on plasma concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Primary hypergammaglobulinemic purpura associated with IgG2 deficiency. A case report.

Hypergammaglobulinemic purpura is a rare disease in children. We report a case of a 12 year-old girl with a history of frequent infections. We found the presence of IgG2 deficiency despite polyclonal hypergammaglobulinemia. An IgG subclass determination should be obtained in every child with polyclonal hypergammaglobulinemia and features of immunodeficiency.

Reduced spinal bone density in young women with amenorrhoea.

To assess the influence of diminished oestrogen production on bone density, we studied 23 amenorrhoeic women and 20 controls (age range 16-29 years) divided into four groups: group 1: 6 patients with idopathic hypogonadotrophic hypogonadism with primary amenorrhoea (IHH); group 2: 5 patients with delayed puberty owing to thalassaemia major (TM); group 3: 12 patients with secondary hypothalamic amenorrhoea (HA); group 4: 20 women with normal menses (controls). Secondary sexual characteristics had developed in all except the women with TM. Groups 1 and 2 had never menstruated and group 3 had been amenorrhoeic for 6 months to 3 years. The control group was studied during the follicular phase of the cycle. None of the patients were taking oestrogens at the time of observation. Plasma concentrations were determined for 17 beta-oestradiol (E2), deidroepiandrosterone sulphate (DHEA-S), cortisol (F), prolactin (PRL), thyroid hormones (T3 and T4), and gonadotrophins (LH and FSH). Spinal bone mineral density (BMD g/cm2) was assessed by dual photon absorbiometry. BMD (mean +/- 1SD) was reduced in the patients (group 2: 0.920 +/- 0.95; group 1: 0.980 +/- 0.94; and group 3: 1.037 +/- 0.75) as compared with the controls (1.290 +/- 0.95) (P less than 0.01). In the three groups of patients, plasma E2 levels were lower than 50 pg/ml and were positively correlated with the BMD. As expected, plasma gonadotrophin levels were highly and significantly reduced (P less than 0.01) in the patients, compared with that of the controls. These results suggest that reduced spinal BMD in hypogonadic women may be related to the lack of oestrogenic influence on bone metabolism.(ABSTRACT TRUNCATED AT 250 WORDS)

Recombinant growth hormone treatment in short patients with thalassemia major: results after 24 and 36 months.

Treatment with recombinant growth hormone (rhGH), 0.6 IU/kg/week s.c., previously successfully conducted for one year, was continued in 15 (Group A) and 8 (Group B) short thalassemia major patients with reduced GH reserve, for two and three years, respectively. In Group A, height for chronological age (Ht SDSCA) increased significantly (p = 0.021) from the start of treatment, but the positive effect was only apparent because of the concomitant slight worsening of height for bone age (Ht SDSBA). Median deltaHt SDSCA/deltaHt SDSBA was <1.0 with respect to both the start (0.87) and the end of the first year of rhGH therapy (0.89). IGF-I levels increased significantly (p = 0.043) compared with values both at the start and at the end of the first year of rhGH therapy. In Group B neither Ht SDSCA nor Ht SDSBA differed statistically from starting values, the former having a positive trend and the latter a negative one. Median deltaHt SDSCA/deltaHt SDSBA was 0.92 with respect to the start, and 0.94 with respect to the end of the second year. IGF-I levels increased significantly (p = 0.043) with respect to starting values. Our data show that the encouraging results described from the first year of rhGH treatment did not persist during the second and third years, and we conclude that this is because increase in bone age with continued treatment is equal to, or slightly greater than the height age increase. We propose that patients with thalassemia major with short stature should receive rhGH treatment for only one year, and that more prolonged treatment should be reserved for selected adolescents who have psychological problems due to shortness; for these patients growth acceleration could represent the main goal, even if this leads to a substantially unchanged or slightly decreased final height.

pQCT (quantitative peripheral tomography) and data evaluation of phosphocalcic metabolism in thalassaemic patients.

pQCT is a method which allows the separate determination of cortical and trabecular bone mineral density in the peripheral skeleton. 21 thalassaemic patients (8 females, 13 males) aged from 10 to 32 years, were examined using pQCT at the ultra distal radius to evaluate SSI (Stress-Strain Index). ALP, serum calcium, hydroxyproline, magnesium, IGF-I, and body surface were determined. The results show a good correlation between cortical BMD and age, concentration of hydroxyproline in urine, serum bone Gla protein, body surface index, bone density of trabecular bone and SSI. Good correlation was found between trabecular bone density and age, IGF-I, BGP and PTH, and between SSI and cortical BMD, age and BSI. The linear relationships between age and cortical and trabecular density show an increase of cortical BMD with age and a decrease of trabecular density with age. The same results were obtained considering trabecular and cortical density versus SSI.

Short stature and body proportion in thalassaemia.

Short stature and short trunk have been reported in thalassaemic patients. We report a study on stature and body proportions in 476 patients (2-36 years old) with beta-thalassaemia major, followed in 12 Italian centres. Auxological data (standing height, sitting height, subischial leg length, target height), haematological data (age at first transfusion, age at start of desferrioxamine [DFX] chelation, mean dose of DFX, ferritin values) and information regarding the presence of endocrine disorders and of bone lesions, were collected and analysed according to the age of the patients, in order to investigate the natural history of the disproportion and the role of siderosis, DFX toxicity and endocrine disorders. Our data indicate that about 18% of thalassaemic patients exhibit short stature; disproportion between the upper and lower body segments is present in 14%; however, a short trunk despite normal stature is present in another 40% of patients. This is due to a spinal growth impairment which starts in infancy and progressively aggravates. We think that a short trunk is peculiar to the disease itself; however, other factors such as hypogonadism, siderosis, or DFX-induced bone dysplasia are probably involved in aggravating the body disproportion in these patients.

The outcome of Wilms' tumor in infants. Italy 1970-79.

Thirty-four infants under 1 year of age with Wilms' tumor were diagnosed and treated in 14 Italian pediatric oncology units during 1970-79. The 3-year survival rates decreased with higher group unilateral tumors: 95% in group I Wilms' tumor, 75% in group II and 20% in group III. The survival rates for children with group I and II Wilms' tumor were similar for those who were treated with surgery and chemotherapy and those who also received postoperative radiotherapy. During 1975-79 fewer patients with group I Wilms' tumor received radiotherapy (1 of 11) than during 1970-74 (4 of 6, p less than 0.05). All these children are alive at this writing.

[Congenital fetal neuroblastoma]. / Neuroblastome congénital foetal.

Neuroblastoma are pediatric tumors of neural crest origin, most often localized in adrenal glands and infrequently congenital. We report two fetal cases found at autopsy, performed at 24 and 28 weeks of gestation, respectively. The 24 week old fetus did not show any malformation; systematic histological analysis found neuroblastoma cells in both the adrenal glands and the retroperitoneal fat tissue. The 28 week old fetus was hydropic and exhibited a nodule (3 cm) in the posterior mediastinum, next to the thoracic spinal cord. This tumor responded to a neuroblastoma associated with small metastatic foci in the adrenal glands, the liver and the frontal brain cortex. The placenta was abnormally heavy and showed hemorrhagic and necrotic areas. Microscopically plugged clumps of neuroblastoma cells were found inside fetal vessels. Immunohistochemistry was employed in both cases and the cells showed immunoreactivity for NSE, NB 84, chromogranin, synaptophysin and neurofilaments, while desmin, MIC 2, and protein S-100 were negative. Congenital neuroblastomas are rare and, to our knowledge this is the thirteenth report of congenital neuroblastoma associated with placental metastasis.

[Idiopathic thrombocytopenic purpura and food allergy: a study on possible correlations]. / Porpora trombocitopenica idiopatica ed allergia alimentare: uno studio sulle possibili correlazioni.

UNLABELLED: Eight children affected by idiopathic chronic thrombocytopenia were studied for history of food allergy, anti-platelet antibodies, total IgE, prick test for food antigens, AGA and EMA. They were free of treatment for thrombocytopenia since at least six months before. Three children had in the first year of life intolerance to cow's milk proteins with atopic dermatitis and/or poor growth. None had AGA or EMA positivity. 6/8 had positivity for anti-platelet antibodies. A 15-days oligoantigenic diet was instituted in all of them. Platelet count was unaffected in all but one, in which a sharp increase was noted (from 19x 10(9)/l. to 150x 10(9)/l.). He was a 12-year-old boy with a previous history of cow's milk intolerance and actual skin prick test positivity for casein and lactoglobulin. A one-year follow up for this case was instituted and he was put on two further 15-days periods of oligoantigenic diet, but no change in platelet count was noted any more. CONCLUSION: we were not able to correlate chronic thrombocytopenia to food allergy.

[Use of high-dose intravenous immunoglobulins in pediatric hematology]. / L'uso di immunoglobuline endovena ad alte dosi in ematologia pediatrica.

High-dose intravenous immunoglobulin play a critical role in a lot of pediatric hematologic diseases. In our experience we studied the effects of IVIG treatment in 63 children. They all tolerated IVIG preparations in every infusions; no trouble caused the interruption of treatment. The efficacy is evident in immunomediated diseases, most of all ITP, and controlling septic episodes in immunocompromised patients (ALL, AIDS, marrow bone transplantation). An important problem is the cost of preparation; but we may consider that this treatment, for example in ITP, reduces hospitalization for children, necessity of platelets' transfusions, use of steroids and, therefore, their collateral effects. Hence, we assert that the social cost of the management of ITP disease is not higher in children treated with IVIG. Furthermore, short hospitalization for IVIG therapy contributes to accept this disease. It should be advisable to make controlled studies to define with more accuracy the role of this preparation and the modality of its use in the different clinical conditions in which it is employed.

[Hypochromic hyposideremic anemia as the first symptom of gastroesophageal reflux]. / Anemia ipocromica iposideremica come primo sintomo di reflusso gastroesofageo.

In a five months infant is described by authors iron deficiency anaemia as early symptom of gastroesophageal reflux undiagnosed previously. Laboratory evaluation excluded any haematological pathology; thereafter clinical suspicion was confirmed by radiological exams and oesophageal PH-monitoring.

[Melorheostosis linear scleroderma with osteopoikilosis. Description of a clinical case]. / Sclerodermia lineare meloreostotica con osteopecilia. Descrizione di un caso clinico.

A case of melorheostosis with osteopoikilosis and linear scleroderma is reported. The authors emphasize the rarity of the disease, the complexity of the therapeutic approach to the patient.