Preparation of Aligned Ultra-long and Diameter-controlled Silicon Oxide Nanotubes by Plasma Enhanced Chemical Vapor Deposition Using Electrospun PVP Nanofiber Template

Well-aligned and suspended polyvinyl pyrrolidone (PVP) nanofibers with 8 mm in length were obtained by electrospinning. Using the aligned suspended PVP nanofibers array as template, aligned ultra-long silicon oxide (SiOx) nanotubes with very high aspect ratios have been prepared by plasma-enhanced chemical vapor deposition (PECVD) process. The inner diameter (20–200 nm) and wall thickness (12–90 nm) of tubes were controlled, respectively, by baking the electrospun nanofibers and by coating time without sacrificing the orientation degree and the length of arrays. The micro-PL spectrum of SiOx nanotubes shows a strong blue–green emission with a peak at about 514 nm accompanied by two shoulders around 415 and 624 nm. The blue–green emission is caused by the defects in the nanotubes

Overexpression of c-erbB2 is a negative prognostic factor in anaplastic astrocytomas

The epidermal growth factor receptor (EGFR) family, consisting of four tyrosine kinase receptors, c-erbB1-4, seems to be influential in gliomagenesis. The aim of this study was to investigate EGFR gene amplification and expression of c-erbB1-4 receptor proteins in human anaplastic astrocytomas. Formalin-fixed and paraffin-embedded sections from 31 cases were investigated by standard immunohistochemical procedures for expression of c-erbB1-4 receptor proteins using commercial antibodies. EGFR gene amplification was studied by fluorescence in situ hybridization using paraffin-embedded tissues. Two monoclonal antibodies, NCL-EGFR-384 and NCL-EGFR, were used for EGFR detection and they displayed positive immunoreactivity in 97% and 71%, respectively. For c-erbB2 detection three monoclonal antibodies, CB11, 3B5, and 5A2, were applied and they displayed positive immunoreactivity in 45%, 100%, and 52%, respectively. Positive immunostaining for c-erbB3 and c-erbB4 was encountered in 97% and 74%, respectively. The EGFR gene was amplified in 9 out of 31 tumors (29%). After adjusting for age, Karnofsky performance status, and extent of surgical resection, Cox multiple regression analysis with overall survival as the dependent variable revealed that c-erbB2 overexpression detected by the monoclonal antibody clone CB11 was a statistically significant poor prognostic factor (P = 0.004). This study shows the convenience and feasibility of immunohistochemistry when determining the expression of receptor proteins in tissue sections of human astrocytomas. The synchronous overexpression of c-erbB1-4 proteins in anaplastic astrocytomas supports their role in the pathogenesis of these tumors. Further, c-erbB2 overexpression seems to predict aggressive behaviour

RBS-channeling and EPR studies of damage in 2 MeV Al2+-implanted 6H-SiC substrates

International audience6H-SiC single crystalline substrates were implanted at room temperature with 2 MeV Al2+ ions to fluences from 2x10(14) Al-2, cm(-2) to 7x10(14) Al2+ cm(-2) and with different current densities (from 6.6 to 33x10(10) Al2+ cm(-2) s(-1)). The depth profile of the damage induced by the Al2+ ions was determined by Backscattering Spectrometry in channeling geometry (BS/C) with a 3.5 MeV He2+ beam. The BS/C spectra were evaluated using the RBX. code. The samples were subsequently annealed at 1100° C in N-2 for one hour, in order to analyze their structural recovery by BS/C and the amount of the remaining defects by means of Electron Paramagnetic Resonance (EPR). The results from the BS/C spectra corresponding to the as-implanted samples indicate that the damage depends strongly on the total fluence but also, although to a lesser extent, on the beam current density. The BS/C measurements reveal that all the samples, except the one implanted with the highest fluence, recover completely their original crystalline structure after the annealing. Furthermore the angular anisotropy of the EPR spectra indicates that the implanted region recovered a good crystallinity, although some residual defects were observed

A clinical trial of progesterone for severe traumatic brain injury.

BACKGROUND: Progesterone has been associated with robust positive effects in animal models of traumatic brain injury (TBI) and with clinical benefits in two phase 2 randomized, controlled trials. We investigated the efficacy and safety of progesterone in a large, prospective, phase 3 randomized clinical trial. METHODS: We conducted a multinational placebo-controlled trial, in which 1195 patients, 16 to 70 years of age, with severe TBI (Glasgow Coma Scale score, 648 [on a scale of 3 to 15, with lower scores indicating a reduced level of consciousness] and at least one reactive pupil) were randomly assigned to receive progesterone or placebo. Dosing began within 8 hours after injury and continued for 120 hours. The primary efficacy end point was the Glasgow Outcome Scale score at 6 months after the injury. RESULTS: Proportional-odds analysis with covariate adjustment showed no treatment effect of progesterone as compared with placebo (odds ratio, 0.96; confidence interval, 0.77 to 1.18). The proportion of patients with a favorable outcome on the Glasgow Outcome Scale (good recovery or moderate disability) was 50.4% with progesterone, as compared with 50.5% with placebo. Mortality was similar in the two groups. No relevant safety differences were noted between progesterone and placebo. CONCLUSIONS: Primary and secondary efficacy analyses showed no clinical benefit of progesterone in patients with severe TBI. These data stand in contrast to the robust preclinical data and results of early single-center trials that provided the impetus to initiate phase 3 trials. (Funded by BHR Pharma; SYNAPSE ClinicalTrials.gov number, NCT01143064.)