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The electrical properties of a single facet of an individual ZnO microwire were investigated. Electrode patterns with a Hall bar structure were deposited on the surface of the top facet of the ZnO microwire. Using a suspended and cross-linked poly(methyl methacrylate) ribbon structure, it was possible to define the electrical connections only at the top surface, while avoiding those on the other five sides of the ZnO microwire. Current-voltage characteristics were examined, and Hall measurements were conducted with various magnetic fields. Through our device structure, the electrical properties could be directly probed at specific points on the ZnO surface in a reliable manner. The estimated electrical characteristics demonstrate that the carrier concentration and mobility of the ZnO surface varied along the axial direction of the wire. These results indicate that the charge carrier concentration on the surface of the micro-/nanowire can be sensitively changed according to the synthesis environment. In addition, it is worth noting that the nanoscale local Hall probes, fabricated by our technique, could probe the very slight variation of carrier concentration, which is difficult to detect by a standard transport measurement along the wire.

Background/aim Asian Traditional medicines are renowned for their antitumor properties and are efficacious in the clinical treatment of various cancer types. ERM210 is a Korean traditional medicine comprising nine types of medicinal plants. In the present study, we examined the pro-apoptotic effect and molecular mechanisms of the effects of ERM210 on HepG2 liver cancer cells. Materials and methods The cytotoxicity of ERM210 on HepG2 cells was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and wound-healing assays, and apoptosis and signaling pathways by fluorescence microscopy flow cytometry and western blotting. Results ERM210 significantly impaired HepG2 cell viability and enhanced mitochondria-dependent cellular apoptosis in a time- and dose-dependent manner by up-regulating the expression of caspases 3, 7 and 9, and of BCL2 apoptosis regulator (BCL2)-associated X, apoptosis regulator (BAX) proteins, whilst down-regulating that of BCL2 protein. Furthermore, ERM210 treatment increased accumulation of cellular and mitochondrial reactive oxygen species (ROS) and significantly inhibited cell migration. Additionally, all these phenomena were reversed by treating with the ROS scavenger N-acetylcysteine. The analysis of signaling proteins revealed that ERM210 significantly up-regulated the phosphorylation of ROS-dependent mitogen-activated protein kinases (p38, extracellular-regulated kinase, and c-Jun N-terminal kinase in HepG2 liver cancer cells. Conclusion ERM210 exerts anticancer effects in HepG2 liver cancer cells by up-regulating ROS/mitochondria-dependent apoptosis signaling, providing new insight into the possibility of employing this traditional medicine for the clinical treatment of liver cancer.

Dynamic surface modification of suspended graphene at high temperatures was directly observed with in situ scanning transmission electron microscopy (STEM) measurements. The suspended graphene devices were prepared on a SiN membrane substrate with a hole so that STEM observations could be conducted during Joule heating. Current-voltage characteristics of suspended graphene devices inside the STEM chamber were measured while monitoring and controlling the temperature of graphene by estimating the electrical power of the devices. During the in situ STEM observation at high temperatures, residual hydrocarbon adsorbents that had remained on graphene effectively evaporated creating large, atomically clean graphene areas. At other places, dynamic changes in the shape, position, and orientation of adsorbents could be directly observed. The temperature of the suspended graphene sample was estimated to reach up to 2000 K during the experiment, making graphene an efficient high-temperature micrometer-sized electron-transparent hot plate for future experiments in microscopes.

Picrasma quassioides (D. Don) Benn is an Asian shrub with a considerable history of traditional medicinal use. P. quassioides and its extracts exhibit good therapeutic properties against several diseases, including anti-inflammatory, antibacterial and anticancer effects. However, the composition of compounds contained in P. quassioides is complex; although various studies have examined mixtures or individual compounds extracted from it, studies on the application of P. quassioides extracts remain limited. In the present review, the structures and functions of the compounds identified from P. quassioides and their utility in anti-inflammatory, anticancer and neuroprotectant therapies was discussed. The present review provided up-to-date information on pharmacological activities and clinical applications for P. quassioides extracts.

How innate lymphoid cells (ILCs) secrete cytokines is not well understood. High mobility group box (HMGB) may be involved in secreting IL17 or IL22 in ILCs. Extracellular HMGB1 may be related with the pathogenesis of Sjögren syndrome. We here investigated that administration of anti-HMGB1 might attenuate dry eyes by modulating ILCs in mouse model of Sjögren syndrome. This study was conducted in conformance with the FASEB Statement of Principles for the use of animals in research and education. 10 weeks-old NOD. B10 or B6 mice had been subconjunctivally injected by 0.02 to 2 ug of anti-HMGB1 antibodies or PBS for 2 weeks. Injection of anti-HMGB1 attenuated corneal epithelial erosions significantly by fluorescein staining and increased tear secretion transiently by phenol-red thread test. After stimulation of the cells from Peyer’s patches or cervical drainage lymph nodes by IL1b and IL23, cells were negatively gated using anti-mouse CD3-PerCP-Cy5.5 and B220-FITC, and were positively gated using anti-mouse CD45-APC-Cy7, NKp46-APC and IL22-PE. The percentages and the numbers of NKp46+IL22 or NKp46-IL22 secreting cells were increased in cervical lymph nodes of anti-HMGB1 injected mice compared with those in PBS injected mice. While, those were not significantly changed in Peyer’s patches of anti-HMGB1 or PBS injected mice. Together, data demonstrate that administration of anti-HMGB1 attenuates dry eyes by increasing IL-22-secreting ILCs in mouse model of Sjögren syndrome.