Hormonal replacement therapy in adolescents and young women with chemo- or radio-induced premature ovarian insufficiency: Practical recommendations.

In women with premature ovarian insufficiency (POI), hormonal therapy (HT) is indicated to decrease the risk of morbidity and to treat symptoms related to prolonged hypoestrogenism. While general recommendations for the management of HT in adults with POI have been published, no systematic suggestions focused on girls, adolescents and young women with POI following gonadotoxic treatments (chemotherapy, radiotherapy, stem cell transplantation) administered for pediatric cancer are available. In order to highlight the challenging issues specifically involving this cohort of patients and to provide clinicians with the proposal of practical therapeutic protocol, we revised the available literature in the light of the shared experience of a multidisciplinary team of pediatric oncologists, gynecologists and endocrinologists. We hereby present the proposals of a practical scheme to induce puberty in prepubertal girls and a decisional algorithm that should guide the clinician in approaching HT in post-pubertal adolescents and young women with iatrogenic POI.

Final height in growth hormone-deficient childhood cancer survivors after growth hormone therapy.

PURPOSE: Growth hormone deficiency (GHD) is the most prevalent hypothalamic-pituitary (HP) disorder found in childhood cancer survivors (CCS). The published studies assessing GHD in CCS concluded that recombinant human GH (rhGH) does not restore final height (FH) to that predicted from mid-parental height (MPH). Thus, wider analyses on final height outcomes after rhGH in CCS are needed. METHODS: Retrospective study on final height (FH) in 87 CCS treated with rhGH. Patients were divided into: Group A (n =48) who underwent cranial radiotherapy or had non-irradiated tumours of HP area, and B (n =39) who were treated with craniospinal or total body irradiation (TBI). 19/87 patients with central precocious/early puberty also received GnRH analogues. RESULTS: Height (HT) gain after 1 and 2 years of rhGH was 0.38 ± 0.35 SDS and 0.18 ± 0.30 SDS, respectively (P < 0.0001); mean FH was in the normal range (- 0.85 ± 1.34 SDS), though not significantly different from HT SDS at baseline. 67% overall failed to reach MPH especially in Group B (P < 0.0001). However, height loss (HT SDS-MPH SDS) at FH improved or remained stable compared to baseline in 26/45 patients (58%). On stepwise regression analysis, major determinants of FH were HT at baseline (P < 0.0001) and delay before start of rhGH (P = 0.012). There was no significant difference in FH when GnRHa was added to rhGH. CONCLUSION: rhGH and GnRH analogues therapy, when indicated, though failing to induce catch-up growth, prevented further height loss leading to a FH within the normal range but still below MPH, this latter being statistically significant in children who received craniospinal and TBI.

The use of recombinant human growth hormone in patients with Mucopolysaccharidoses and growth hormone deficiency: a case series.

BACKGROUND: The treatment with recombinant human growth hormone in patients affected by Mucopolysaccharidoses (MPS) is considered whenever a concurrent diagnosis of growth hormone deficiency is demonstrated. The short- and long-term effects of recombinant human growth hormone in this selected cohort is still debated, given the natural progression of disease-related skeletal malformations and the paucity of treated patients reported in literature. The presented case series provides detailed information about the response to recombinant growth hormone in MPS patients diagnosed with growth hormone deficiency. CASES PRESENTATION: The growth patterns of 4 MPS female patients (current age: 11.7-14.3 years) treated with recombinant human growth hormone due to growth hormone deficiency have been retrospectively analyzed. Two patients, diagnosed with MPS IH, had undergone haematopoietic stem cell transplantation at an early age; the remaining two patients were affected by MPS IV and VI and were treated with enzyme replacement therapy. 4/4 patients presented with a progressive growth deceleration before the diagnosis of growth hormone deficiency was confirmed. This trend was initially reverted by a remarkable increase in height velocity after the start of recombinant growth hormone. We recorded an average increase in height velocity z-score of + 4.23 ± 2.9 and + 4.55 ± 0.96 respectively after 6 and 12 months of treatment. After the first 12-24 months, growth showed a deceleration in all the patients. While in a girl with MPS IH recombinant human growth hormone was discontinued due to a lack in clinical efficacy, 3/4 patients grew at a stable pace, tracking the height centile achieved after the cited initial increase in height velocity. Furthermore, mineral bone density assessed via bone densitometry, showed a remarkable increase in the two patients who were tested before and after starting treatment. CONCLUSIONS: Recombinant human growth hormone appears to have effectively reverted the growth deceleration experienced by MPS patients diagnosed with growth hormone deficiency, at least during the first 12-24 months of treatment.

Growth optimization and characterization of regular arrays of GaAs/AlGaAs core/shell nanowires for tandem solar cells on silicon.

With a band gap value of 1.7 eV, Al0.2Ga0.8As is one of the ideal III-V alloys for the development of nanowire-based Tandem Solar Cells on silicon. Nevertheless, growing self-catalysed AlGaAs nanowires on silicon by solid-source molecular beam epitaxy is a very difficult task due to the oxidation of Al adatoms by the SiO2 layer present on the surface. Here we propose a nanowire structure including a p.i.n radial junction inside an Al0.2Ga0.8As shell grown on a p-GaAs core. The crystalline structure of such self-catalysed nanowires grown on an epi-ready Si(111) substrate (with a thin native SiO2 layer) was investigated by transmission electronic microscopy and photoluminescence. I(V) measurements performed on single nanowires have shown a diode-like behaviour corresponding to the radial p.i.n junction inside the Al0.2Ga0.8As shell. Moreover, a current generation under the electron beam was evidenced over the entire radial junction along the nanowires by means of electron beam induced current (EBIC) microscopy. The same structure was reproduced on patterned substrates with a SiO2 mask, producing an ordered hexagonal array. High and uniform yields from 83% to 87% of vertical nanowires were obtained on 0.9 × 0.9 cm2 patterned areas. EBIC mapping performed on these nanowires confirmed the good electrical properties of the radial junction within the nanowires.

Far-field optical control of a movable subdiffraction light grid.

We demonstrate experimentally a subdiffraction light pattern, with a period down to 150 nm, at the surface of an optimized silicon nanostructured thin film. We show, using near-field and far-field characterization, that this subdiffraction pattern can be translated and rotated just by changing the illumination angle. The movable high frequency light pattern paves the way for subdiffraction resolution surface imaging microscopy without scanning near-field probes.