Role of Btg2 in the Progression of a PDGF-Induced Oligodendroglioma Model

Tumor progression is a key aspect in oncology. Not even the overexpression of a powerful oncogenic stimulus such as platelet derived growth factor-B (PDGF-B) is sufficient per se to confer full malignancy to cells. In previous studies we showed that neural progenitors overexpressing PDGF-B need to undergo progression to acquire the capability to give rise to secondary tumor following transplant. By comparing the expression profile of PDGF-expressing cells before and after progression, we found that progressed tumors consistently downregulate the expression of the antiproliferative gene Btg2. We therefore tested whether the downregulation of Btg2 is sufficient and necessary for glioma progression with loss and gain of function experiments. Our results show that downregulation of Btg2 is not sufficient but is necessary for tumor progression since the re-introduction of Btg2 in fully progressed tumors dramatically impairs their gliomagenic potential. These results suggest an important role of Btg2 in glioma progression. Accordingly with this view, the analysis of public datasets of human gliomas showed that reduced level of Btg2 expression correlates with a significantly worse prognosis.     

Operator equalisation for bloat free genetic programming and a survey of bloat control methods

Bloat can be defined as an excess of code growth without a corresponding improvement in fitness. This problem has been one of the most intensively studied subjects since the beginnings of Genetic Programming. This paper begins by briefly reviewing the theories explaining bloat, and presenting a comprehensive survey and taxonomy of many of the bloat control methods published in the literature through the years. Particular attention is then given to the new Crossover Bias theory and the bloat control method it inspired, Operator Equalisation (OpEq). Two implementations of OpEq are described in detail. The results presented clearly show that Genetic Programming using OpEq is essentially bloat free. We discuss the advantages and shortcomings of each different implementation, and the unexpected effect of OpEq on overfitting. We observe the evolutionary dynamics of OpEq and address its potential to be extended and integrated into different elements of the evolutionary process.     

The use and nature of present-focused interventions in cognitive and behavioral therapies for depression.

To improve cognitive and behavioral therapies (CBT) for depression, several approaches recommend an increased focus on the occurrence of problems as they occur in the therapeutic relationship or in relation to the live therapy process, referred to as present-focused. A lingering question has been the degree to which CBT therapists already engage in present-focused work. This study utilized sessions from recent trials of CBT for depression and, in Phase I, raters identified present-focused interventions on a turn-by-turn basis. Phase II raters used a qualitative analysis to determine categories of present-focused interventions. Results indicated that therapists rarely focused on the therapeutic relationship; when they did, it was often transient and lacking in the elaborations suggested by newer approaches. Therapists more often performed therapy process and emotion focused interventions, but these also tended to lack elaboration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Synthesis of poly(ester amide)s composed of lactic acid and glycolic acid units by the bulk polycondensation of metal halide salts

Thermal polycondensation of the potassium salt of N‐methylchloroacetyl‐6‐aminohexanoic acid (LAHK) was found to be effective in the preparation of a new poly(ester amide) based on lactic acid units with a high yield and a moderate molecular weight. The reaction started in the solid state and proceeded through the formation of potassium chloride salt as the driving force. The use of a monomer having an amide linkage diminished the secondary reactions previously found in the synthesis of polylactide from 2‐halogenopropionates. The polymerization of potassium salt of N‐chloroacetyl‐6‐aminohexanoic acid (GAHK) took place in a similar temperature range as that of the 2‐chloropropionyl derivative; in this way, it was possible to conduct the copolymerization processes. The polymerization kinetics of LAHK and its mixture with GAHK was studied by Fourier transform infrared spectroscopy. The bulk polycondensation reaction was faster for GAHK than for LAHK, but the kinetic differences were not significant enough to prevent copolymerization at a temperature close to 160°C. Therefore, new degradable materials with tuned properties according to the glycolic acid/lactic acid content were obtained. ¹H‐NMR spectroscopy was useful for following the time evolution of the copolymerization process and for determining the final composition. Calorimetric data showed that all of the samples were thermally stable and that decreases in the melting temperature and enthalpy were observed at intermediate compositions. The existence of an eutectic point became proof that effective copolymerization was achieved in the thermal polycondensation process. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43197.     

Identification of Bioactivity,Volatile and Fatty Acid Profile in Supercritical Fluid Extracts of Mexican arnica

Supercritical fluid extraction (SFE) is a sustainable technique used for the extraction of lipophilic metabolites such as pigments and fatty acids. Arnica plant is considered a potential candidate material with high antioxidant and antimicrobial activities. Therefore, in this study, a locally available Heterotheca inuloides, also known as Mexican arnica, was analyzed for the extraction of high-value compounds. Based on different pressure (P), temperature (T), and co-solvent (CoS), four treatments (T) were prepared. A maximum 7.13% yield was recovered from T2 (T = 60 °C, P = 10 MPa, CoS = 8 g/min), followed by 6.69% from T4 (T = 60 °C, P = 30 MPa, CoS = 4 g/min). Some bioactive sesquiterpenoids such as 7-hydroxycadalene, caryophyllene and δ-cadinene were identified in the extracts by GC/MS. The fatty acid profile revealed that the main components were palmitic acid (C16:0), followed by linoleic acid (C18:2ω6c), α-linolenic acid (C18:3ω3) and stearic acid (C18:0) differing in percent yield per treatment. Antibacterial activities were determined by the agar diffusion method, indicating that all the treatments exerted strong antibacterial activity against S. aureus, C. albicans, and E. coli strains. The antioxidant capacity of the extracts was also measured by three in vitro assays, DPPH, TEAC and FRAP, using Trolox as a standard. Results showed high antioxidant capacity enabling pharmaceutical applications of Mexican arnica.