University of Minho

About: University of Minho is a education organization based out in Braga, Portugal. It is known for research contribution in the topics: Context (language use) & Population. The organization has 10585 authors who have published 34736 publications receiving 732436 citations. The organization is also known as: Universidade do Minho & UMinho.

Relationships between perceived parental involvement in homework, student homework behaviors, and academic achievement: differences among elementary, junior high, and high school students

Abstract: This study aims to produce a deeper understanding of the relationship between perceived parental homework involvement (i.e., parental homework control and parental homework support), student homework behaviors (i.e., time spend on homework completion, time management, and amount of homework completed), and student academic achievement. Using Mplus5.1, a structural equation model was fit for 1683 students at different stages of schooling (i.e., elementary school − 5th and 6th grades; junior high school − 7th and 8th grades; and high school − 9th and 10th grades). The data showed that student homework behaviors, perceived parental homework involvement, and academic achievement are significantly related. However, results vary depending on the students’ grade level: (a) in junior high and high school, perceived parental homework involvement is related to students’ homework behaviors, but not in elementary school; and (b) although students’ homework behaviors are related to academic achievement at each school level, the direction and magnitude of the relationships vary. Specifically, the relationship between perceived parental homework involvement and academic achievement is stronger in junior high and high school than in elementary school; and student homework behaviors mediate the association between perceived parental homework involvement (control and support) and academic achievement only in junior high and high school.

Reversing HOXA9 Oncogene Activation by PI3K Inhibition: Epigenetic Mechanism and Prognostic Significance in Human Glioblastoma

Abstract: HOXA genes encode critical transcriptional regulators of embryonic development that have been implicated in cancer. In this study, we documented functional relevance and mechanism of activation of HOXA9 in glioblastoma (GBM), the most common malignant brain tumor. Expression of HOXA genes was investigated using reverse transcription-PCR in primary gliomas and glioblastoma cell lines and was validated in two sets of expression array data. In a subset of GBM, HOXA genes are aberrently activated within confined chromosomal domains. Transcriptional activation of the HOXA cluster was reversible by a phosphoinostide 3-kinase (PI3K) inhibitor through an epigenetic mechanism involving histone H3K27 trimethylation. Functional studies of HOXA9 showed its capacity to decrease apoptosis and increase cellular proliferation along with tumor necrosis factor-related apoptosis-including ligand resistance. Notably, aberrant expression of HOXA9 was independently predictive of shorter overall and progression-free survival in two GBM patient sets and improved survival prediction by MGMT promoter methylation. Thus, HOXA9 activation is a novel, independent, and negative prognostic marker in GBM that is reversible through a PI3K-associated epigenetic mechanism. Our findings suggest a transcriptional pathway through which PI3K activates oncogenic HOXA expression with implications for mTOR or PI3K targeted therapies.

Drug release of pH/temperature-responsive calcium alginate/poly(N-isopropylacrylamide) semi IPN beads

Abstract: Summary: A series of semi-interpenetrating, polymernetwork (semi-IPN), hydrogel beads, composed of calciumalginate (Ca-alginate) and poly(N-isopropylacrylamide)(PNIPAAM), were prepared for a pH/temperature-sensitivedrug delivery study. The equilibrium swelling showed theindependent pH- and thermo- responsive nature of thedeveloped materials. At pH¼2.1, the release amount ofindomethacin incorporated into these beads was about 10%within 400 min, while this value approached to 95% atpH¼7.4.Thereleaserateofthedrugwashigherat378Cthanthat at 258C and increased slightly with increasingPNIPAAM content. These results suggest that the Ca-alginate/PNIPAAM beads have the potential to be used asan effective pH/temperature sustainable delivery system ofbioactive agents.A summary of the temperature- and pH-dependence on therelease of the drug over a period of 450 min. The effect of thetemperatureontheswellingofthebeadsisshownintheinset. Macromol. Biosci. 2006, 6, 358–363 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

A distinct spectrum of copy number aberrations in pediatric high-grade gliomas.

Abstract: Purpose: As genome-scale technologies begin to unravel the complexity of the equivalent tumors in adults, we can attempt detailed characterization of high-grade gliomas in children, that have until recently been lacking. Toward this end, we sought to validate and extend investigations of the differences between pediatric and adult tumors. Experimental Design: We carried out copy number profiling by array comparative genomic hybridization using a 32K bacterial artificial chromosome platform on 63 formalin-fixed paraffin-embedded cases of high-grade glioma arising in children and young people ( Results: The genomic profiles of these tumors could be subclassified into four categories: those with stable genomes, which were associated with a better prognosis; those with aneuploid and those with highly rearranged genomes; and those with an amplifier genotype, which had a significantly worse clinical outcome. Independent of this was a clear segregation of cases with 1q gain (more common in children) from those with concurrent 7 gain/10q loss (a defining feature of adults). Detailed mapping of all the amplification and deletion events revealed numerous low-frequency amplifications, including IGF1R, PDGFRB, PIK3CA, CDK6, CCND1 , and CCNE1 , and novel homozygous deletions encompassing unknown genes, including those at 5q35, 10q25, and 22q13. Despite this, aberrations targeting the “core signaling pathways” in adult glioblastomas are significantly underrepresented in the pediatric setting. Conclusions: These data highlight that although there are overlaps in the genomic events driving gliomagenesis of all ages, the pediatric disease harbors a distinct spectrum of copy number aberrations compared with adults. Clin Cancer Res; 16(13); 3368–77. ©2010 AACR.