Search

Recently, a novel host, K3SiF7, for Mn4+-activated phosphors was discovered and it was revealed that Mn4+-doped K3SiF7 has an advantage in decay time compared with the most widely used Mn4+-doped K2SiF6. Here, we developed an organic solvent-assisted synthetic method for the K3SiF7:Mn4+ phosphor. To the best of our knowledge, it is the first publication about a newly developed synthetic method of the K3SiF7:Mn4+ phosphor. Various organic solvents with different functional groups have been tried to synthesize the K3SiF7:Mn4+ phosphor. When we introduced oleylamine (OAm) as an organic solvent, uniform K3SiF7:Mn4+ particles below 5 μm were obtained at a lower temperature than the conventional solid state reaction (SSR). As a result of thermal quenching (TQ) and 85/85 tests, it was confirmed that despite its small size, the resulting K3SiF7:Mn4+ has enhanced stability against heat and moisture with the aid of an organic protecting layer. We expect that this organic solvent-assisted synthesis can be applied to the synthesis of other phosphors with a chemical formula of A3MF7:Mn4+ (A = alkali metal ion; M = Si, Ge, Zr, etc.). [ABSTRACT FROM AUTHOR]

Background/aim: Glioma is often refractory. The accumulation of amyloid beta (Aβ) in the brain is commonly associated with Alzheimer's disease (AD), but there are studies suggesting that Aβ has tumor suppressor potential. The aim of this study was to identify a novel, non-invasive candidate biomarker for histological prediction and prognostic assessment of glioma., Patients and Methods: Serum was prepared from blood samples collected preoperatively from 48 patients with WHO grade II-IV glioma between October 2004 and December 2017 at a single tertiary institution. The concentration of Aβ42 was measured using the SMCxPRO immunoassay (Merck). The clinical and histological characteristics of the patients, including molecular subtypes, were reviewed., Results: The mean age of the patients was 52.2±12.5 years. The mean value of serum Aβ42 concentration was 7.6±7.8 pg/ml in the anaplastic astrocytoma (WHO grade III) group and 6.4±6.5 pg/ml in the glioblastoma multiforme (WHO grade IV) group. The Negative epidermal growth factor receptor (EGFR) expression was associated with higher serum Aβ42 levels (p=0.020). Kaplan-Meier analysis demonstrated that patients with high serum Aβ42 (>11.78 pg/ml) had significantly longer progression-free survival (PFS) (p=0.038) and overall survival (OS) (p=0.018)., Conclusion: This study investigated serum Aβ42 levels as a potential biomarker for glioma. The results showed that low serum Aβ42 levels were associated with EGFR expression and poor PFS and OS. Overall, these findings suggest a potential role of Aβ42 as a prognostic marker in astrocytomas., (Copyright © 2024, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)