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Objective: To investigate the role of Wnt/ß-catenin/TCF-4 pathway in renal cancer cells and to analyze its possible mechanism. Methods: ß-catenin and TCF-4 were inhibited by siRNA in 786-O cells. The proliferation of transfected cells was detected by CCK8. The cell death of transfected cells was detected by acridine orange -ethidium bromide staining. The expressions of TCF-4, bcl-2, bax and Caspase-3 were detected in transfection group, empty vector group and negative control groups by western blot. Results: The cell proliferation ability of the ß-catenin transfection group was significantly lower than that of the control group (0.443±0.145 vs 0.910±0.721), meanwhile, the cell death rate was significantly increased (16.38±5.32 vs 6.61±1.04), the expression level of Caspase 3 and bax was increased, and the expression of anti-apoptotic protein Bcl-2 was decreased. Decreased TCF-4 led to the same results as inhibition of ß-catenin (all P<0.05). Conclusion: The Wnt/ß-catenin/TCF-4 pathway may play a role in the regulation of proliferation and apoptosis in 786-O renal cancer cells. The mechanism might through regulating of the downstream apoptosis proteins Caspase 3, bax and anti-apoptotic protein Bcl-2.

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Long persistent phosphorescence is generally known as a phenomenon involving carrier traps induced by defects or impurities in crystals. In this paper, phosphorescence sustained for tens of minutes was found in intentionally undoped ZnO and it was proposed to be a universal phenomenon in wide bandgap semiconductors upon satisfying several conditions. A new model was built to understand this attractive phenomenon within the framework of the traditional trapping-detrapping model but it was modified by considering the free electrons in the conduction band as a significant contributor to the long persistent phosphorescence besides the electrons trapped by shallow donors. This model, explicitly expressed as I(t) ∝ [1 + M(1 - Fe-γt)-2]e-γt, is not only capable of giving a quantitative description of the non-exponential decay of phosphorescence in a wide temperature range but also enables one to determine the depth of shallow donors in semiconductors. The participation of free electrons in phosphorescence was further confirmed by another carefully designed experiment. Thus, this study may represent significant progress in understanding phosphorescence.

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Anderson localization is a predominant phenomenon in condensed matter and materials physics. In fact, localized and delocalized states often co-exist in one material. They are separated by a boundary called the mobility edge. Mott transition may take place between these two regimes. However, it is widely recognized that an apparent demonstration of Anderson localization or Mott transition is a challenging task. In this article, we present a direct optical observation of a transition of radiative recombination dominant channels from delocalized (i.e., local extended) states to Anderson localized states in the GaInP base layer of a GaInP/GaAs single junction solar cell by the means of the variable-temperature electroluminescence (EL) technique. It is found that by increasing temperature, we can boost a remarkable transition of radiative recombination dominant channels from the delocalized states to the localized states. The delocalized states are induced by the local atomic ordering domains (InP/GaP monolayer superlattices) while the localized states are caused by random distribution of indium (gallium) content. The efficient transfer and thermal redistribution of carriers between the two kinds of electronic states was revealed to result in both a distinct EL mechanism transition and an electrical resistance evolution with temperature. Our study gives rise to a self-consistent precise picture for carrier localization and transfer in a GaInP alloy, which is an extremely technologically important energy material for fabricating high-efficiency photovoltaic devices.

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Goldthread (Coptis chinensis) is an important herbaceous plant in traditional Chinese medicine (3). Annual production of goldthread root is ~3,000 tons (dry weight) in China. The plant is cultivated extensively in Shizhu Co., Chongqing (29.98°E, 108.13°N), where goldthread yields account for more than 60% of total world production. A foliar disease was first observed on goldthread plants in 2008 in Shizhu County (5). In 2011 and 2012, about 10 ha of goldthread fields in different townships of Shizhu Co. were surveyed. The results demonstrated that the disease present in the fields was widespread at incidences of 30 to 100%, with yield losses of 15 to 75%. Typical symptoms included irregular, purple brown lesions on leaves, beginning usually at the leaf margin and extending to the central leaf blade. The lesions coalesced and turned deep purple. Black pycnidia were visible on the lesions, and severely diseased plants were usually wholly blighted. To identify the pathogen, infected leaves were collected from goldthread fields in different townships of Shizhu Co. and small pieces of symptomatic tissue were cut from each leaf. The leaf pieces were surface-disinfected for 1 min in 1.5% sodium hypochlorite, rinsed in sterilized water, air-dried, and transferred onto potato dextrose agar (PDA) plates with 0.5 g/liter of streptomycin sulfate. Thirty-three fungal isolates with similar colony morphology were obtained. On oatmeal agar plates, each colony was circular with a smooth edge, initially cream, and then pale-brown. Pycnidia were dark brown, spherical, with or without papillae, and 100 to 112 × 189 to 222 µm. Conidia were produced on short, straight, and aseptate conidiophores in the pycnidia; they were monocellular, hyaline, ellipsoidal or clavate, and 2.01 to 2.50 × 4.20 to 5.55 µm. Three isolates (SZ-9, SZ-10, and SZ-13) were selected randomly from all 33 isolates, and genomic DNA of each isolate was extracted following the CTAB method (4). The rDNA ITS region of each isolate was amplified with V9G/ITS4 primers and sequenced (1). The ITS sequences of the three isolates (GenBank Accession Nos. KF692355.2 [SZ-9], KF985236.1 [SZ-10], and KF985237.1 [SZ-13]) were identical, and BLAST revealed 100% identity with the ITS sequence of an isolate of Phoma aquilegiicola (CBS 107.96, GU237735.1). Based on the morphological characteristics and ITS sequences, all three isolates were identified as P. aquilegiicola. Pathogenicity test of 10 isolates was conducted by placing a 5-mm-diameter mycelial agar plug (from the margin of a 5-day-old PDA culture) on each of 10 fully-expanded leaves of healthy goldthread plants/isolate. Ten leaves were treated similarly with sterilized PDA plugs as a control. Inoculated and control plants were incubated in the dark for 24 h at 25 ± 2°C and >90% RH, and then maintained in a growth chamber at 25 ± 2°C, 3,100 lux, and >90% RH. The pathogenicity test was carried out three times. Symptoms developed on all inoculated leaves for all 10 isolates, but not on the control plants. Lesions were first visible 48 h after inoculation, and typical irregular lesions similar to those observed on field plants were seen after 6 days. The same pathogenic fungus was re-isolated from the infected leaves but not from the non-inoculated leaves. A disease caused by P. aquilegiicola was first reported on Aquilegia flabellata plants of the cv. Fan Columbine in a perennial garden in Italy (2). This is the first report of leaf spot on goldthread caused by P. aquilegiicola in China. Studies on the epidemiology and control of the disease are necessary owing to the economic significance of the host and destructiveness of the disease. References: (1) M. M. Aveskamp et al. Mycologia 101:363, 2009. (2) A. Garibaldi et al. Plant Dis. 95:880, 2011. (3) B. Liu et al. J. Pharmaceut. Biomed. 41:1056, 2006. (4) M. A. Saghai-Maaroof et al. Proc. Natl. Acad. Sci. USA. 81:8014, 1984. (5) X. R. Zhou et al. J. Shizhen Medicine Res. 23:471, 2012.

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