Background Growing evidences indicate that circular RNAs (circRNAs) play an important role in the regulation of biological behavior of tumor. We aim to explore the role of circRNA in glioma and elucidate how circRNA acts. Methods Real-time PCR was used to examine the expression of circPTN in glioma tissues and normal brain tissues (NBT). Assays of dual- luciferase reporter system, biotin label RNA pull-down and FISH were used to determine that circPTN could sponge miR-145-5p and miR-330-5p. Tumor sphere formation assay was performed to determine self- renewal of glioma stem cell (GSCs). Cell counting Kit-8 (CCK8), EdU assay and flow cytometry were used to investigate proliferation and cell cycle. Intracranial xenograft was established to determine how circPTN impacts in vivo. Tumor sphere formation assay was performed to determine self- renewal of glioma stem cell (GSCs). Results We demonstrated circPTN was significantly higher expression in glioma tissues and glioma cell lines, compared with NBT and HEB (human astrocyte). In gain- and loss-of-function experiments, circPTN significantly promoted glioma growth in vitro and in vivo. Furthermore, we performed dual-luciferase reporter assays and RNA pull-down assays to verify that circPTN acts through sponging miR-145-5p and miR-330-5p. Increasing expression of circPTN rescued the inhibition of proliferation and downregulation of SOX9/ITGA5 in glioma cells by miR-145-5p/miR-330-5p. In addition, we found that circPTN promoted self-renewal and increased the expression of stemness markers (Nestin, CD133, SOX9, and SOX2) via sponging miR-145-5p. Moreover, this regulation was disappeared when circPTN binding sites in miR-145-5p were mutated. Conclusions Our results suggest that circPTN is an oncogenic factor that acts by sponging miR-145-5p/miR-330-5p in glioma.

The uncontrollable rupture of the filament accompanied with joule heating deteriorates the resistive switching devices performance, especially on endurance and uniformity. To suppress the undesirable filaments rupture, this work presents an interface engineering methodology by inducing a thin layer of NiOx into a sandwiched Al/TaOx/ITO resistive switching device. The NiOx/TaOx interface barrier can confine the formation and rupture of filaments throughout the entire bulk structure under critical bias setups. The physical mechanism behind is the space-charge-limited conduction dominates in the SET process, while the Schottky emission dominates under the reverse bias.

In this work plasmon propagation and highly sensitive hydrogen sensing are demonstrated in single‐crystal Pd and its alloy nanowires, based on an evanescent wave coupling technique using optical fiber tapers. The plasmon propagation losses of Pd nanowires on an MgF2 substrate are measured to be ∼2 dB/μm (at 635 nm). Using a suspension scheme of the nanowire, the propagation losses decrease to ∼0.6 dB/μm in air. Utilizing an alloying technique, single‐crystal PdAg nanowires are fabricated and exhibit decreasing and tunable propagation losses. Furthermore, Pd nanowires are used for plasmonic gas sensing with amplitude sensitivity of ∼11 dB to 3.6% hydrogen gas, which is much higher than those in photonic nanowire sensors. The concentration detection limit is about 0.2%, which is lower than those in photonic nanowire sensors and most surface plasmon resonance sensors. The hysteresis effect of the Pd nanowire in hydrogen sensing is suppressed by using single‐crystal PdAu alloy nanowires. This work may find widespread application, ranging from sensing and integrated circuits to materials research.