Treatment of Human Glioblastoma U251 Cells with Sulforaphane and a Peptide Nucleic Acid (PNA) Targeting miR-15b-5p: Synergistic Effects on Induction of Apoptosis

Glioblastoma multiforme (GBM) is a lethal malignant tumor accounting for 42% of the tumors of the central nervous system, the median survival being 15 months. At present, no curative treatment is available for GBM and new drugs and therapeutic protocols are urgently needed. In this context, combined therapy appears to be a very interesting approach. The isothiocyanate sulforaphane (SFN) has been previously shown to induce apoptosis and inhibit the growth and invasion of GBM cells. On the other hand, the microRNA miR-15b is involved in invasiveness and proliferation in GBM and its inhibition is associated with the induction of apoptosis. On the basis of these observations, the objective of the present study was to determine whether a combined treatment using SFN and a peptide nucleic acid interfering with miR-15b-5p (PNA-a15b) might be proposed for increasing the pro-apoptotic effects of the single agents. To verify this hypothesis, we have treated GMB U251 cells with SFN alone, PNA-a15b alone or their combination. The cell viability, apoptosis and combination index were, respectively, analyzed by calcein staining, annexin-V and caspase-3/7 assays, and RT-qPCR for genes involved in apoptosis. The efficacy of the PNA-a15b determined the miR-15b-5p content analyzed by RT-qPCR. The results obtained indicate that SFN and PNA-a15b synergistically act in inducing the apoptosis of U251 cells. Therefore, the PNA-a15b might be proposed in a “combo-therapy” associated with SFN. Overall, this study suggests the feasibility of using combined treatments based on PNAs targeting miRNA involved in GBM and nutraceuticals able to stimulate apoptosis.     

New far-infrared emissions and frequency measurements in hydrazine

By means of a new CO₂ laser we performed a new investigation of the far-infrared laser emission spectrum of hydrazine excited by the 10P(32) and 10R(8) CO₂ laser lines. We found seven new lines and measured the frequency of four of them; moreover we measured the frequencies of two more lines previously reported in the literature with only wavelength measurements. The frequencies of the far-infrared laser emissions have been measured by means of a frequency-synthesis chain based on new InP Schottky diodes. The detected signal was beat-note generated in a Schottky diode between the far-infrared radiation, the harmonics of a 72 GHz frequency reference and a rf signal. We also characterized all of the observed lines by their polarization relative to the pumping CO₂ laser, the optimum pressure and the offset relative to the CO₂ center frequency. PACS 42.55.Lt; 42.62.Fi     

Minimal degree liftings in characteristic 2

In this paper we analyze liftings of hyperelliptic curves over perfect fields in characteristic 2 to curves over rings of Witt vectors. This theory can be applied to construct error-correcting codes; lifts of points with minimal degrees are likely to yield the best codes, and these are the main focus of the paper. We find upper and lower bounds for their degrees, give conditions to achieve the lower bounds and analyze the existence of lifts of the Frobenius. Finally, we exhibit explicit computations for genus 2 and show codes obtained using this theory.     

Optimal control of growth coefficient on a steady-state population model

We study the control problem of maximizing the net benefit in the conservation of a single species with a fixed amount of resources. The existence of an optimal control is established and the uniqueness and characterization of the optimal control are investigated. Numerical simulations illustrate several cases, for both 1D and 2D domains, in which several interesting phenomena are found. Some open problems are discussed.     

Cattle breeding: A fast screening procedure to control the bovine fodder contamination

The European Commission has adopted a large number of emergency measures to prevent the spread of the Bovine spongiform encephalopathy (BSE) in the Member States, and among them, a European Regulation prohibits the feeding to ruminants of animal protein and animal feed containing such protein. Aim of this work has been to propose the thermal analysis as a new rapid and sensitive screening tool for a preliminary determination of possible contamination in products destined to bovine growth, since the possibility to screen the samples by a rapid and sensitive tool could reduce the time of analysis required by the actual methodology and could allow the systematic surveillance of bovine feeding, with the official EU methods applied only to positive samples.     

Degrees of the Elliptic Teichmüller Lift

The purpose of this paper is to find upper bounds for the degrees, or equivalently, for the order of the poles at O, of the coordinate functions of the elliptic Teichmüller lift of an ordinary elliptic curve over a perfect field of characteristic p. We prove the following bounds:ord₀(x_n)?−(n+2)pⁿ+npⁿ⁻¹, ord₀(y_n)?−(n+3)pⁿ+npⁿ⁻¹. Also, we prove that the bound for x_n is not the exact order if, and only if, p divides (n+1), and the bound for y_n is not the exact order if, and only if, p divides (n+1)(n+2)/2. Finally, we give an algorithm to compute the reduction modulo p³ of the canonical lift for p≠2,3.     

GaSb and InAs: New Materials for Metal-Semiconductor Point-Contact Diodes

Metal-semiconductor point contact diodes have proved to be good detectors and mixers for radiation from the far-infrared to visible. Until now GaAs, InSb and InP are the most studied and used semiconductor materials for these devices. In this work we present the performance in the visible and infrared region for metal-semiconductor point-contact diodes with GaSb or InAs as the semiconductor layers. These two new materials have shown good characteristics.