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Small nucleolar RNA host gene 16 (SNHG16) has been documented to be involved in the pathogenesis of human cancers. Here, we elucidated the biological roles and regulatory mechanism of SNHG16 in the pathogenesis of oral squamous cell carcinoma (OSCC). In this paper, we found that c-Myc and SNHG16 were overexpressed in OSCC tissues and cell lines compared with normal tissues and normal human oral keratinocytes cells. There was a notable positive correlation between SNHG16 and c-Myc expression in OSCC tissues. c-Myc silencing by either shRNA c-Myc or by 10058-F4 (c-Myc inhibitor) resulted in a dose-dependent reduction in SNHG16 levels in CAL-27 and TSCCA cells; conversely, upregulation of c-Myc by pcDNA c-Myc markedly increased SNHG16 expression. Depletion of SNHG16 in CAL-27 cells strikingly inhibited cell proliferation, migration and invasion, as indicated by downregulation of proliferating cell nuclear antigen (PCNA), matrix metalloproteinase (MMP)-2 and MMP-9. Moreover, depletion of SNHG16 induced cell apoptosis and inhibited epithelial-to-mesenchymal transition as indicated by induction of cleaved caspase-3 and epithelial cadherin (E-cadherin) along with reduction of N-cadherin and Snail. Intriguingly, c-Myc knockdown led to the similar functional effects as that of SNHG16 knockdown in TSCCA cells. However, these changes caused by c-Myc knockdown were abrogated by SNHG16 overexpression. Knockdown of SNHG16 conspicuously repressed tumor growth in nude mice. Similarly, silencing of c-Myc markedly inhibited tumor growth and reduced SNHG16 expression in nude mice. Moreover, overexpression of SNHG16 blocked the inhibitory effect of c-Myc silencing on tumor growth in vivo. Thus, we conclude that c-Myc-induced upregulation of SNHG16 enhances progression and carcinogenesis in OSCC.

Based on potential vorticity (PV) thinking, northeast China cold vortex (NCCV) corresponds to an upper‐level high PV anomaly from stratospheric PV downward intrusion. Within a vortex, latent heating from precipitation would produce a vertical dipole of PV anomalies that would affect structures and evolution of the vortex. In this paper, three‐dimensional structures and evolution of NCCV and, effects of latent heating from precipitation along bent‐back, cold and warm fronts on them are investigated based on convection‐allowing simulations for an intense NCCV case during 8–17 June 2012. Trajectory analysis shows that the negative upper‐level diabatic PV anomaly from bent‐back frontal precipitation, near the vortex center, is the dominant contributor to erosion of high PV in the vortex core region as it is advected in, leading to the weakening of the vortex. The negative PV anomalies along the cold and warm fronts, at the east‐to‐southeast side of the vortex, are mostly advected downstream away from the NCCV. In the middle troposphere, positive PV anomalies are primarily generated along fronts and the accumulated positive PV anomalies filling the vortex region help to reinforce the low‐level cyclonic circulation. The lower‐level PV is affected by surface heating and cooling through their effects on static stability, but such effects are periodic and create mainly diurnal variations. The NCCV eventually decays as the upper‐level vortex weakens due to significant PV erosion. Northeast China cold vortex (NCCV) is responsible for much of the warm season precipitation in northeast China. Based on convection‐allowing simulations of a characteristic case, the distribution and effects of latent heating release from precipitation in bent‐back, cold and warm frontal regions on the structures and evolution of potential vorticity (PV) within the NCCV are studied. Negative upper‐level PV anomalies generated at the bent‐back front are primarily responsible for the filamentation and erosion of high PV in the core of NCCV, leading to the weakening of the vortex. At middle‐to‐low levels, positive PV anomalies generated reinforce the low‐level circulations. However, the lower‐level PV exhibits a significant diurnal cycle, which is mainly affected by the surface heating and cooling through reducing static stability at daytime and increasing static stability during night. The overall system eventually decays as the upper‐level vortex weakens. Precipitation in northeast China cold vortex produces negative upper‐level potential vorticity (PV) anomaly that weakens the upper level cold vortexNegative PV anomaly produced at the bent‐back front is the dominant contributor to the erosion of upper‐level high PV in the vortex centerLower‐level vortex is enhanced by positive PV anomaly from precipitation, and the PV has diurnal variations due to surface heating/cooling Precipitation in northeast China cold vortex produces negative upper‐level potential vorticity (PV) anomaly that weakens the upper level cold vortex Negative PV anomaly produced at the bent‐back front is the dominant contributor to the erosion of upper‐level high PV in the vortex center Lower‐level vortex is enhanced by positive PV anomaly from precipitation, and the PV has diurnal variations due to surface heating/cooling

This study unveils the evolution of two major early signals in the North Pacific atmosphere-ocean system that heralded abnormal high-pressure blockings and cold-vortex activities across Northeast China, based on an analysis of the configurations of major modes including the polar vortex, the North Pacific Oscillation (NPO), and SST in the preceding winter and spring and atmospheric low-frequency disturbances in Northeast China. We analyzed these aspects to understand the atmosphere-ocean physical coupling processes characterized by the two early signals, and here we explain the possible mechanisms through which dipole circulation anomalies affect the summer low-temperature processes in Northeast China. We further analyzed the interdecadal variation background and associated physical processes of the two early signals.

Well-defined, modular dendrimers enable processing techniques and electronic properties to be tuned independently. Moreover, the dendritic topology can isolate the core chromophore, thus reducing or eliminating strong intermolecular interactions. This paper presents the synthesis of three series of flexible, dendron-functionalized dendrimers as red-light-emitting materials by a convergent approach: (1) carbazole (CZ) or oxadiazole (OXZ) terminated imide-type dendrimers, (2) cascade energy-transferring imide-type dendrimers, and (3) CZ-terminated perylene bay-type dendrimers. They all consist of the luminescent core of perylenebis(dicarboximide)s with specific functional groups of CZ or OXZ at the periphery and are constructed from flexible Fréchet-type poly(aryl ether) dendrons. The chemical structures of the dendrons and dendrimers were determined by standard spectroscopic techniques including 1H and 13C NMR spectroscopy and low/high-resolution mass spectrometry (ESI or MALDI-TOF). The dendrimers are designed on the basis of the following considerations: (1) dendron functionalization to incorporate CZ or OXZ units to realize the carrier-injection adjustment, (2) tuning or improving solubility, functionality, glass-transition temperature (Tg) with well-defined dendrons, and (3) avoiding luminescence quenching with the help of high site-isolation of dendrons to enhance core luminescence. DSC results indicate that the incorporation of Fréchet-type poly(aryl ether) dendrons can improve the amorphous properties and increase Tg. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

Three novel dendritic europium complexes containing grafted carbazole units as their functional peripheries were prepared and characterized. The Förster energy transfer from the peripheries of carbazole units to β-diketonates as well as from the ligands to the central Euiii ions in these complexes has been demonstrated. Under the indirect excitation of carbazole units, a characteristic red emission peak at 615 nm due to the Euiii ion transition of 5D0→ 7F2was observed for the complexes in solution or solid films. As a result of the light-harvesting and site isolation of carbazole dendrons, compared with the reference compound EuBPPD3Phen, PL efficiencies of EuMCPD3Phen, EuBCPD3Phen and EuTCPD3Phen in the film state are 3.3, 7.9 and 4.5 fold increased, respectively. Notably, white light emission with the CIE coordinates of 0.333, 0.348 has been achieved with a single dopant of EuTCPD3Phen in an EL device of configuration ITONPBCBP : EuTCPD3PhenBCPMg : Ag. Its maximum external quantum efficiency is more than 1.1 and maximum brightness reached 229 cd m−2. The origin of the blue and green emission is attributed to the dendron-grafted carbazole units forming an exciplex and an electroplex with CBP 4,4′-N,N′-dicarbazole biphenyl and ligand β-diketonate, respectively. The results suggest that modifying ligands can not only tune the carrier-transporting properties of complexes, but also provide a useful clue to the use of electroplexes or exciplexes to realize broad or even white electroluminescence.

A novel dendritic europium complex Eu(TCPD)3(Phen) with carbazole units as the periphery has been prepared and the device ITO//NPB//CBP:Eu(TCPD)3(Phen)//BCP//Mg:Ag gave out white light with the CIE coordinate (0.333, 0.348) at 16.2 V and maximum external quantum efficiency of 1.1%.