Johannes Kepler University of Linz

About: Johannes Kepler University of Linz is a education organization based out in Linz, Oberösterreich, Austria. It is known for research contribution in the topics: Thin film & Quantum dot. The organization has 6605 authors who have published 19243 publications receiving 385667 citations.

TERT promoter mutations are associated with poor prognosis and cell immortalization in meningioma.

Abstract: Background Meningiomas are mostly benign tumors tending to progress to higher-grade lesions. Mutations in the telomerase reverse transcriptase (TERT) gene promoter are comparably rare in meningioma, but were recently suggested to predict risk of recurrence and progression. Here we have analyzed a cohort of World Health Organization grades I-III meningiomas regarding the impact of TERT promoter mutations on patient prognosis and in vitro cell propagation feasibility. Methods From 110 meningioma patients, 128 tissue samples were analyzed for the TERT promoter mutations C228T and C250T by direct sequencing. Of the 128 samples, 121 were tested for cell propagation in vitro. Telomerase activity, TERT mRNA expression, and telomere lengths were investigated by telomeric repeat amplification protocol assay, reverse transcription PCR, and quantitative PCR, respectively. Impact of the E-twenty-six (ETS) transcription factor inhibitor YK-4-279 on cell viability and TERT promoter activity was analyzed. Results TERT promoter mutations were found in 5.5% of all samples analyzed and were associated with a significantly upregulated telomerase activity and TERT mRNA expression (P < 0.0001 both). Regarding telomere lengths, no significant difference between the TERT promoter wild-type and mutated subgroups was detected. Patients with TERT promoter mutated tumors exhibited significantly shorter overall survival (P = 0.0006; 53.8 vs 115.6 mo). The presence of TERT promoter mutations but not telomerase activity or TERT mRNA expression predicted indefinite cell growth in vitro. TERT promoter mutated meningioma cells were hypersensitive against the ETS transcription factor inhibitor YK-4-279, inducing a distinct downregulation of TERT promoter activity. Conclusion TERT promoter mutations drive meningioma aggressiveness, resulting in reduced patient survival, but might also open novel therapeutic options for progressive disease.

Spectral and Directional Reshaping of Fluorescence in Large Area Self-Assembled Plasmonic–Photonic Crystals

Abstract: Spectral and directional reshaping of fluorescence from dye molecules embedded in self-assembled hybrid plasmonic–photonic crystals has been examined. The hybrid crystals comprise two-dimensional h...

How do family ownership and founder management affect capital structure decisions and adjustment of SMEs? Evidence from a bank-based economy

Abstract: Purpose – The purpose of this paper s to study the financing behavior of family firms (FF), as these differ from their small- and medium-sized enterprise (SME) counterparts in their capital structure decision, mainly due to an increased risk aversion and the desire to maintain control over the firm. Design/methodology/approach – A sample of 470 SMEs from a bank-based environment is examined for the period of 2005-2010. A dynamic panel data model is utilized to assess both the role of several capital structure determinants and the target-adjusting behavior for different subsamples of firms. Findings – The results show that FF, whether controlled by founders or not, are relatively more leveraged. The aim to maintain long-term control and limited financing options and other factors seem crucial to the observed differences in leverage and dominate risk considerations associated with higher debt. Presumed differences in agency costs across generations do not drive capital structure decisions, as overall levera...