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An attempt was made to identify the less severe cases of precocious puberty and to describe their natural course. A group of 17 girls with precocious puberty and a bone age advance over chronological age of less than two years (group 1) was compared with a group of 19 patients with severe precocious puberty and bone age advance of two years or more (group 2). Mean (SEM) plasma oestradiol concentrations were 82 (30) pmol/l and 164 (21) pmol/l (p less than 0.05), vaginal maturation indexes were 16 (5) and 41 (4), and plasma somatomedin C concentrations were 1.0 (0.2) U/ml (n = 8) and 2.1 (0.3) U/ml (n = 16) in groups 1 and 2, respectively. The time between onset and diagnosis of secondary sexual characteristics was about one year in both groups. After two years' follow up the untreated patients in group 1 had maintained their predicted final height. These changes were in contrast to those observed at first examination in patients in group 2 who had a mean (SD) predicted final height of -1.3 (0.2) and a mean bone age advance of 3.0 (0.2) years. These data show that bone age advance to chronological age, and plasma somatomedin C concentrations measured at initial evaluation are helpful in identifying less severe and potentially slow progressing forms of central precocious puberty. [ABSTRACT FROM AUTHOR]

To ensure patient care in an oncological fertility preservation (FP) programme, specialists must provide technology that best suits the patients' clinical conditions. In vitro oocyte maturation (IVM) and ovarian tissue cryopreservation (OTC) are possible fertility preservation treatments for women in need of urgent oncological treatment. IVM consists of the retrieval of immature oocytes from small antral follicles, with no or minimal ovarian stimulation by gonadotropins. Therefore, IVM has become a pertinent option for fertility preservation, especially for cases whereby ovarian stimulation is unfeasible or contra-indicated. Existing data on immature oocytes, retrieved transvaginally (OPU-IVM) or extracted from ovarian tissue 'ex vivo' (OTO-IVM), are still limited on technical consistency, efficacy, and safety. The present retrospective cohort study includes 89 women undergoing fertility preservation using IVM methodologies and 26 women undergoing ovarian stimulation (OS) in concomitant period. In total, 533 immature oocytes were collected from IVM patients, achieving a maturation rate of 57% and 70% in OTO-IVM and 73% and 82% in OPU-IVM at 24 h and 48 h in culture, respectively. The observed high maturation rates might be due to the use of patients' serum in its innate status, i.e., without heat-inactivation. This permitted 7.6 ± 5.7 and 4.6 ± 4.9 oocytes to be vitrified in OTO-IVM and OPU-IVM, respectively, compared to 6.8 ± 4.6 from OS patients. Regarding OS patients, two of them underwent embryo transfer following the insemination of warmed oocytes after complete remission, resulting in a single live birth from one patient. Upon follow-up of two OTO-IVM patients after the termination of their oncological treatment, a total of 11 warmed oocytes lead to a transfer of a single embryo, but pregnancy was not achieved. From OPU-IVM, six embryos were transferred in three patients 4.25 years after oocyte vitrification, leading to the live birth of a healthy boy. The present case of live birth is among the first cases reported so far and supports the notion that IVM might be a relevant and safe FP option for cancer patients when oocyte preservation is required but ovarian stimulation is contra-indicated.

A piezoelectric plate, poled along its thickness and supporting on its top and bottom surfaces a periodic grating of electrodes, is considered. An analytical model allowing band structure calculation is derived for the first symmetrical mode propagating along the length of the plate. Analytical results show that an electrical Bragg (EB) bandgap can be observed for this mode, depending on the electrical boundary conditions applied on the electrodes. This "EB bandgap" is associated with a discontinuity of the electric field between two successive unit cells. These results are validated with the numerical simulations based on the finite element method. Analytical and numerical results prove that the EB bandgap is highly tunable and can be optimized by changing the crystallographic orientation of the material. A simple tunable filter exploiting this bandgap is designed and fabricated. Experimental results of electrical impedance and electrical potential at the output together with a scanning laser vibrometer analysis are presented, which confirm the theoretical predictions.

Background: HIV infection and progression to AIDS is characterized by the depletion of T cells, which could be due, in part, to apoptosis mediated by the extra-cellular HIV-encoded Tat protein as a consequence of Tat binding to tubulin. Microtubules are tubulin polymers that are essential for cell structure and division. Molecules that target microtubules induce apoptosis and are potent anti-cancer drugs. We studied the effect on tubulin polymerization of three Tat variants: Tat HxB2 and Tat Eli from patients who are rapid progressors (RP) and Tat Oyi from highly exposed but persistently seronegative (HEPS) patients. We compared the effect on tubulin polymerization of these Tat variants and peptides corresponding to different parts of the Tat sequence, with paclitaxel, an anti-cancer drug that targets microtubules., Results: We show that Tat, and specifically, residues 38-72, directly enhance tubulin polymerization. We demonstrate that Tat could also directly trigger the mitochondrial pathway to induce T cell apoptosis, as shown in vitro by the release of cytochrome c from isolated mitochondria., Conclusions: These results show that Tat directly acts on microtubule polymerization and provide insights into the mechanism of T cell apoptosis mediated by extra-cellular Tat.

This study concerns the immunoreactive somatomedin C secretion by prepubertal rabbit epiphyseal chondrocytes cultured in a defined serum-free medium. In such culture conditions, chondrocytes mainly synthesized Type II collagen (80% of total collagen) during 10 days. A small amount of Type I collagen was also found with a significant (p less than 0.05) higher level during the period of cell multiplication (6.4 +/- 1.5%) than when cells reached confluency (0.9 +/- 0.2%). During the 10 days of culture without serum and without hormone added, a Sm-C/IGF1 activity was measured by RIA at a mean level of 30 +/- 5 mU/ml/10 micrograms DNA. This value was significantly higher (p less than 0.001) than in the medium not incubated with the cells (1.7 +/- 0.9 mU/ml). When hGH was added to the culture medium during the period of cell division, the level of Sm-C/IGF1 activity was significantly elevated at 39 +/- 4 mU/ml/10 micrograms DNA (p less than 0.05) and at 55 +/- 3 mU/ml/10 micrograms DNA (p less than 0.001) with 50 ng/ml and 100 ng/ml hGH concentrations respectively. On the contrary, no difference was observed at confluency in treated and non treated cells.

This study demonstrates that cytolytic T-cell lines exhibit progressive in-vitro modifications of their phenotype and of their growth behaviour and may use different pathways for their multiplication. Comparing three established cell lines, we firstly demonstrated that the expression of LFA-I is stable but the Lyt 2, 3 is rapidly lost. In this case, a high lectin-dependent cytotoxicity appears. Secondly, we demonstrated that two of the cell lines used the interleukin 2-interleukin 2 receptors (IL-2-IL-2R) binding pathway. Two different monoclonal antibodies showed that the IL-2 receptors distribution does not correlate with the number of functional sites which determines the IL-2 requirement. In contrast, the third cell line, although bearing high levels of IL-2 receptors, grows without the addition of IL-2; this cell growth is not inhibited by anti-IL-2 receptors monoclonal antibodies. Thirdly, it appears that the new property of IL-2 independence is associated with acquisition of the simultaneous capacity to induce tumour grafts in nude mice. As it has been recently reported that cytolytic T-lymphocytes against tumour cells could be promising immunotherapeutic agents, the spontaneous malignant transformation of such CTL lines should be taken into account before using them for adoptive immunotherapeutic purposes.