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Head and neck squamous cell carcinoma (HNSCC) represents more than 5% of all cancers diagnosed annually in United States and around the world. Despite advances in the management of patients with this disease, the survival has not been significantly improved, and the search for potential alternative therapies is encouraging. Here we demonstrate that deguelin administration causes a significant HNSCC cell death. Deguelin induces both cell apoptosis and autophagy by modulating multiple signaling pathways in cultured HNSCC cells. Deguelin inhibits Akt signaling, and down-regulates survivin and cyclin-dependent kinase 4 (Cdk4) expressions, by disrupting their association with heat shock protein-90 (Hsp-90). Deguelin induces ceramide production through de novo synthase pathway to promote HNSCC cell death. Importantly, increased ceramide level activates AMP-activated protein kinase (AMPK), which then directly phosphorylates Ulk1 and eventually leads to cell autophagy. We found that a low dose of deguelin sensitized HNSCC cells to 5-FU. Finally, using a nude mice Hep-2 xenograft model, we also showed a significant anti-tumor ability of deguelin in vivo. Together, we suggest that deguelin may represent a novel and effective chemo-agent against HNSCC. [ABSTRACT FROM AUTHOR]

An optimal design of two dimensional (2D) hexagonal photonic bandgap (PBG) resonating micro-optical defect cavity on IV-VI lead salt material has been carried out. The nature of both the transverse electric (TE) and transverse magnetic (TM) band structure for the electromagnetic waves in the periodic triangular lattice pattern is formulated by the well-established plane wave expansion (PWE) method. The defect cavity is engineered to resonate at ~4.17 µm in TM bandgap. The field distribution in the defect cavity has been analyzed based on two very efficient and popular schemes - perturbation correction finite difference (FD) method and finite difference time domain (FDTD) mechanism which is truncated by uniaxial perfectly matched layer (UPML) absorbing boundary condition (ABC). FD method efficiently solves Helmholtz equations to evaluate the field distribution in the semiconducting waveguide for any single spectral wavelength. The numerical results by FD method are re-established by the FDTD scheme that incorporates a precise numerical analysis within a specified wavelength range. [ABSTRACT FROM AUTHOR]

We present a detailed study on the surface morphologies and chemical composition of growth pits in lead selenide (PbSe) epilayers grown by molecular-beam epitaxy. Various growth pits were investigated by scanning electron microscopy and energy-dispersive x-ray analysis. The vast majority of growth pits within the PbSe epilayers contained either single or multiple PbSe microcrystals with a distinct cuboid shape. Based on the observed structures and morphologies of the PbSe microcrystals, the formation mechanism of the cuboid structures was considered to be (100) preferential crystal growth originating from PbSe polycrystalline seeds. [ABSTRACT FROM AUTHOR]

Abstract  In this paper, the synthesis principles and methods of 1,1-spiro(ethylenediamino)-3,3,5,5-tetrachlorocyclotriphosphazene (ETCCTP) and its nitration product of 1,1-spiro(N,N′-dinitroethylenediamino)-3,3,5,5-tetrachlorocyclotriphosphazene (DNETCCTP) have been reported. Their structures were demonstrated by elemental analysis, NMR, MS, and FTIR methods. Besides, the crystal of the title compound was obtained and characterized by X-ray single-crystal diffraction technique. The obtained results showed that the crystal belongs to Crystal system of Monoclinic with space group of C2/c. Based on the crystal data, geometries and normal vibrations have been obtained by using the B3LYP method with the 6-31G**, 6-311G**, and 6-31++G** basis sets. The calculation results further demonstrate the molecular structure of the title compound. [ABSTRACT FROM AUTHOR]

Aimed to control the interfacial reaction in Al18B4O33/Al composites, the artificial nitridation process is proposed based on thermodynamic calculations, which leads to a 50-nm thick artificial nitrided coating surrounding a Al18B4O33 whisker. Aluminum (AC8A) matrix composites reinforced with different Al18B4O33 whiskers were processed and Al18B4O33 whiskers were used in their as-received form and after artificial nitridation. The interface region between the aluminum matrix and Al18B4O33 was charactered using transmission electron microscopy. Results show that extensive reaction takes place during the incorporation process between the as-received Al18B4O33 whiskers and the aluminum matrix and Mg in the base alloy forms MgAl2O4 spinel phases. Such interfacial reaction is enhanced after T6 heat treatment. In the case of artificially nitrided Al18B4O33 whiskers, even though the artificial nitrided coating surrounds the Al18B4O33 whisker, it can react with the AC8A alloy to produce MgAl2O4, but the degree of the interfacial reaction is reduced. The interfacial reaction only consumes the artificial nitrided coating instead of the reinforcement whiskers and the integrity of the whisker is preserved. [ABSTRACT FROM AUTHOR]

The traditional method for processing multi-beam real-time attitude compensation data did not consider the influence of attitude compensation error, which left attitude residual in data. So a new method for processing multi-beam data of real-time attitude compensation was proposed. By studying the nature of attitude compensation error, the calculation method of systematic attitude compensation error was put forward. The concept of correction threshold was introduced and the specific determination method was given. Finally, combining with the principle of real-time attitude compensation, a systematic attitude compensation error correction method, which makes use of a tracking algorithm considering attitude to make secondary attitude correction, was proposed, and the specific processing flow was given. By comparing the data processing accuracy of the tradition method and the new method, the results showed that the new method can effectively reduce the influence of systematic attitude compensation error, and significantly improve the data processing accuracy.

The backscattering intensity collected by multi beam sonar system and scanning sonar system can be used to classify seabed bottom characteristics. However, there are many problems that have not been solved in the practical application. This paper attempts to sort out and analyze the problems encountered in the classification process and put forward some solutions. The relationship among acoustic image, seabed topography and sediment is analyzed

Abstract Background Ticks are distributed worldwide and considered as vectors of many human diseases. Tick defensins, a family of antimicrobial peptides, form the first line of defense against pathogens. Findings A defensin-like gene, named Ds-defensin, was identified from a cDNA library of the hard tick Dermacentor silvarum collected from northeast China. The full-length cDNA of Ds-defensin was 225 bp, encoding a 74 amino acid peptide. The nucleotide sequence of Ds-defensin shared 98.2% similarity to putative defensin from Dermacentor marginatus. RT-PCR results suggested that Ds-defensin was extensively expressed in tick salivary gland and midgut, with a higher expression level in midgut. Ds-defensin showed broad antimicrobial activity against various Gram-positive and Gram-negative bacteria, as well as the fungus Candida albicans. Conclusions We characterized a functional defensin from D. silvarum of China. Ds-defensin showed bactericidal activity against various Gram-positive and Gram-negative bacteria. Ds-defensin can be expected to be introduced to the medical field as a new molecule with antibacterial activity.

We report the enhancement of the mid-infrared (MIR) luminescence intensity in a nanoscale metal/semiconductor structure by the coupling of surface plasmon polaritons (SPPs) with excitons in a narrow-gap semiconductor. The SPPs are efficiently excited by the total internal reflection photons at a metal/semiconductor interface. The intense electric field induced by SPPs, in turn, greatly changes the radiative recombination rates of the excitons generated by the pumping laser and thus the MIR luminescence intensity. The finding avails the understanding of fundamental science of SPs in narrow-gap semiconductors and the development of novel MIR devices. [ABSTRACT FROM AUTHOR]

Abstract Background The current study aimed to investigate the dynamic alteration and prognostic significance of tumor‐infiltrating lymphocytes (TILs), tumor‐associated macrophages (TAMs), and PD‐L1 status of immune cells in muscle‐invasive bladder cancer (MIBC) treated with neoadjuvant chemotherapy (NAC). Methods Multiplex immunofluorescence staining was performed to examine CD68+ TAM, CD4+ T cell, CD8+ T cell, FOXP3+ Treg cell, and PD‐L1 expression in paired MIBC tissues (n = 54) before and after NAC. Patients were then divided into definite responders (DR), (≤pT1) and incomplete responders (IR). Results There was no significant difference between DR and IR cohorts for the immune cell infiltration levels at the baseline status. Tobacco history was identified to be associated with worse NAC efficacy. CD68+ (stroma area: p = 0.025; tumor area: p = 0.028; total area: p = 0.013) and CD68+PD‐L1− (stroma area: p = 0.035; tumor area: p = 0.013 total area: p = 0.014) TAMs infiltration levels decreased significantly after NAC, while there was no significant difference of CD68+PD‐L1+ and TILs. The infiltration of CD68+ (p = 0.033), CD68+PD‐L1− (p = 0.033), and CD68+PD‐L1+ (p

Abstract Targeting angiogenesis has been considered a promising treatment for a large number of malignancies, including osteosarcoma. Bevacizumab (Bev) is an anti-vascular endothelial growth factor being used for this purpose. We herein investigate the therapeutic potential of Bev in angiogenesis during osteosarcoma and the related mechanisms. Bioinformatics were performed for identification of osteosarcoma-related microarray dataset to collect related lncRNA and miRNA, with MIAT and miR-613 obtained. The predicted binding site between miR-613 and GPR158 3′UTR region was further confirmed by luciferase assay. Then, their effects combined with treatment with Bev on osteosarcoma cells were explored by the gain- and loss-of-function. After extraction from osteosarcoma patients’ serum (serum-EVs) and identification, EVs were co-cultured with osteosarcoma cells, the biological behaviors of which were detected by CCK-8 assay and microtubule formation in vitro. A mouse tumor xenograft model was used to determine the effect of Bev on tumor angiogenesis in vivo. Bev inhibited osteosarcoma cell proliferation and angiogenesis in vivo and in vitro. Besides, serum-EVs could transfer MIAT (EV-MIAT) into osteosarcoma cells, where it is competitively bound to miR-613 to elevate GPR158, thus promoting osteosarcoma cell proliferation and angiogenesis. Furthermore, Bev arrested osteosarcoma cell proliferation and angiogenesis by inhibiting EV-MIAT and inducing miR-613-mediated GPR158 inhibition. In conclusion, the Bev-mediated MIAT/miR-613/GPR158 regulatory feedback revealed a new molecular mechanism in the pathogenesis of osteosarcoma angiogenesis.

Objective: This study aimed to address the status, role, and mechanism of sympathetic nerve infiltration in the progression of stomach adenocarcinoma (STAD). Methods: Sympathetic nerve and its neurotransmitter NE, β-ARs, and associated signaling molecules in the STAD tissues and the adjacent tissues from 46 STAD patients were examined using immunostaining, HPLC, and western blotting. The effects and mechanisms of β2-AR activation on the proliferation, migration and invasion of AGS and SGC-7901 gastric cancer (GC) cell lines were examined using CCK-8, transwell, and western blotting assays. Correlations between genes and STAD survival were analyzed using bioinformatics. Results: Striking sympathetic nerve infiltration, elevations of NGF, TrkA, GAP43, TH, S100, NE, β2-AR, YKL-40, syndecan-1, MMP9, CD206, and CD31 were observed in the STAD tissues compared to the adjacent tissues. Activation of β2-AR in the two GC cell lines significantly amplified the expressions of NGF, YKL-40, MMP9, syndecan-1, p-STAT3 and p-ERK, and increased GC cell proliferation, migration and invasion. Bioinformatic analyses revealed positive correlations of NGF, β2-AR, syndecan-1, and macrophage infiltration, respectively, with low survival of STAD, of β2-AR respectively with STAT3, ERK1/2 (MAPK1/3), YKL-40, MMP9, and syndecan-1, and of YKL-40 with MMP9. Conclusion: Sympathetic nerves significantly infiltrated into human STAD tissues as a result of high NGF and TrkA expressions; elevated NE led to overactivation of β2-AR-STAT3/ERK-YKL-40 signaling pathway, and finally caused cancer cell growth and invasion, M2 macrophage infiltration, angiogenesis, matrix degradation and STAD metastasis and progression.

We report a feasible method to realize tunable surface plasmon-polariton (SPP) resonance in organic light-emitting devices (OLEDs) by employing corrugated Ag-Al alloy electrodes. The excited SPP resonance induced by the periodic corrugations can be precisely tuned based on the composition ratios of the Ag-Al alloy electrodes. With an appropriate composition ratio of the corrugated alloy electrode, the photons trapped in SPP modes are recovered and extracted effectively. The 25% increasement in luminance and 21% enhancement in current efficiency have been achieved by using the corrugated Ag-Al alloy electrodes in OLEDs.

The lattice-structure-mismatched CdTe/PbTe heterostructures are emerging materials with unique properties and promising applications in midinfrared optoelectronics and spintronics. High-density two-dimensional electron gas at the metastable twisted interfaces of CdTe/PbTe (111) is investigated experimentally and theoretically. CdTe thin films grown on PbTe(111) using molecular-beam epitaxy are found to have high electron mobilities and carrier concentrations from Hall-effect measurements: 2.02×104 cm2/V s and 4.5×1018 cm-3 at 2 K, and 6.70×103 cm2/V s and 6.0×1019 cm-3 at 77 K. Our density-functional theory modeling reveals that the epitaxially grown CdTe/PbTe (111) heterostructures form metastable twisted interfaces that exhibit unusual structural and electronic properties: (1) The PbTe epilayer on CdTe(111) substrates is structurally highly distorted from the rocksalt structure within the first ~4.5 nm from the interface, which is caused by the stereochemical activity of the Pb s2 lone pair. (2) The CdTe eplilayer on the PbTe(111) forms spontaneously a high density two-dimensional electron gas (2DEG) over 1013 cm-2 near the interface, without the need for doping, which explains the experimentally observed high carrier density and mobility. It is a much simpler heterostructure yet able to offer high electron mobility comparable to and one or two order magnitude higher sheet carrier density than the best achieved values for those of Si and II-VI based quantum well structures relying on modulation doping. [ABSTRACT FROM AUTHOR]

Master regulator transcription factors TP63 and SOX2 have been reported to overlap in genomic occupancy in squamous cell carcinomas (SCCs). Here, the authors demonstrate that TP63 and SOX2 promote co-operatively long non-coding RNA CCAT1 expression through activating its super-enhancer, and CCAT1 forms a complex with TP63 and SOX2, which regulates EGFR super-enhancers and enhances both the MEK/ERK1/2 and PI3K/AKT signaling pathways in SCC.

Flexible perovskite solar cells (pero-SCs) have drawn much attention due to their high efficiency and low cost. Indium tin oxide (ITO) and fluorine-doped SnO2 as the most commonly used transparent electrodes in pero-SCs, unfortunately, exhibit poor mechanical stability in flexible devices. We demonstrate flexible pero-SCs based on an ultrathin Au electrode with perfect performance of transmittance, conductivity, and mechanical stability. The ultrathin Au electrode with the thickness of 7 nm is prepared on the SU-8/Ca modified substrate, and the Volmer-Weber growth mode of deposited metal film has been suppressed successfully by the chemical and physical bonding from the SU-8/Ca hybrid modification layer. The ITO-free flexible pero-SCs based on ultrathin Au electrodes achieve the power conversion efficiency of 11.44%, and nearly 82% of the initial efficiency remains after approximately 2400 bending cycles, demonstrating the high flexibility and mechanical stability of the ultrathin Au electrode as well as the ITO-free pero-SCs. [ABSTRACT FROM AUTHOR]

Highly stretchable organic light-emitting diodes tend to suffer from a lack of mechanical robustness. Here, Yin et al. fabricate ordered buckled films by laying flexible light-emitting diodes on laser-ablated, prestretched substrates. The devices exhibit good emission stability over 15,000 stretching cycles.

The indium–tin-oxide-free organic solar cells (OSCs) have been fabricated using a semitransparent Au film as anode. A comparative study between the OSCs with different metal cathodes shows that formation of an ideal ohmic contact at low-workfunction Ca and the organic interface reduces series resistance and increases the carrier collection. Moreover, a periodic corrugation was introduced into the device structure, which leads to an enhanced light absorption in the OSCs by elongating the optical path of the incident light inside the absorber material. The highest power conversion efficiency of an optimal OSC with a Au anode and a corrugated Ca/Ag cathode is 1.4%, which is significantly improved in contrast to 0.61% for the OSC with a planar Al cathode.