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11.
Sleep apnea syndrome (SAS) is characterized by recurrent episodes of oxygen desaturation and reoxygenation (intermittent hypoxia [IH]), and is a risk factor for cardiovascular disease (CVD) and insulin resistance/Type 2 diabetes. However, the mechanisms linking IH stress and CVD remain elusive. We exposed rat H9c2 and mouse P19.CL6 cardiomyocytes to experimental IH or normoxia for 24 h to analyze the mRNA expression of several cardiomyokines. We found that the mRNA levels of regenerating gene IV (Reg IV) and hepatocyte growth factor (Hgf) in H9c2 and P19.CL6 cardiomyocytes were significantly increased by IH, whereas the promoter activities of the genes were not increased. A target mRNA search of microRNA (miR)s revealed that rat and mouse mRNAs have a potential target sequence for miR-499. The miR-499 level of IH-treated cells was significantly decreased compared to normoxia-treated cells. MiR-499 mimic and non-specific control RNA (miR-499 mimic NC) were introduced into P19.CL6 cells, and the IH-induced upregulation of the genes was abolished by introduction of the miR-499 mimic, but not by the miR-499 mimic NC. These results indicate that IH stress downregulates the miR-499 in cardiomyocytes, resulting in increased levels of Reg IV and Hgf mRNAs, leading to the protection of cardiomyocytes in SAS patients.  相似文献   
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For sp2 or sp3 carbon material growth, it is important to investigate the precursors or intermediates just before growth. In this study, the density of ethylene (C2H4) outside the plasma discharge space and just before reaching the carbon nanotube (CNT) growth region is investigated by vacuum ultraviolet absorption spectroscopy for plasma discharge in an antenna‐type remote plasma chemical vapor deposition with a CH4/H2 system, with which the growth of very long (≈0.5 cm) CNT forests is achieved. Single‐wall CNT forests have the potential for application as electrodes in battery cells, vertical wiring for high current applications, and thermal interface materials. It is observed that the plasma discharge decomposes the CH4 source gas and forms C2Hx species, which reversibly reform to C2H4 in the plasma‐off state. In addition, the density of the formed C2H4 has a strong correlation to the CNT growth rate. Therefore, the C2H4 density is a good indicator of the density of C2Hx species for CNT growth in the CH4/H2 plasma system.  相似文献   
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Genetically encoded caged amino acids can be used to control the dynamics of protein activities and cellular localization in response to external cues. In the present study, we revealed the structural basis for the recognition of O-(2-nitrobenzyl)-L-tyrosine (oNBTyr) by its specific variant of Methanocaldococcus jannaschii tyrosyl-tRNA synthetase (oNBTyrRS), and then demonstrated its potential availability for time-resolved X-ray crystallography. The substrate-bound crystal structure of oNBTyrRS at a 2.79 Å resolution indicated that the replacement of tyrosine and leucine at positions 32 and 65 by glycine (Tyr32Gly and Leu65Gly, respectively) and Asp158Ser created sufficient space for entry of the bulky substitute into the amino acid binding pocket, while Glu in place of Leu162 formed a hydrogen bond with the nitro moiety of oNBTyr. We also produced an oNBTyr-containing lysozyme through a cell-free protein synthesis system derived from the Escherichia coli B95. ΔA strain with the UAG codon reassigned to the nonnatural amino acid. Another crystallographic study of the caged protein showed that the site-specifically incorporated oNBTyr was degraded to tyrosine by light irradiation of the crystals. Thus, cell-free protein synthesis of caged proteins with oNBTyr could facilitate time-resolved structural analysis of proteins, including medically important membrane proteins.  相似文献   
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The authors present a one-chip scalable 8×8 shared buffer switch LSI which includes a 256-cell buffer. Speedup, flow control, and input slot rotation functions are provided in order to interconnect LSIs for scaling-up without degrading cell loss rates. Computer simulations show that these functions bring a satisfactory result and can make the cell loss- rate for a Clos three-stage network superior to that for the output buffer switch which includes the same amount of buffer space. A 0.8 μm BiCMOS process is employed for this LSI. The total number of transistors is one million. This LSI has already been fabricated  相似文献   
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Automatic sketch colourization is a highly interestinged topic in the image-generation field. However, due to the absence of texture in sketch images and the lack of training data, existing reference-based methods are ineffective in generating visually pleasant results and cannot edit the colours using text tags. Thus, this paper presents a conditional generative adversarial network (cGAN)-based architecture with a pre-trained convolutional neural network (CNN), reference-based channel-wise attention (RBCA) and self-adaptive multi-layer perceptron (MLP) to tackle this problem. We propose two-step training and spatial latent manipulation to achieve high-quality and colour-adjustable results using reference images and text tags. The superiority of our approach in reference-based colourization is demonstrated through qualitative/quantitative comparisons and user studies with existing network-based methods. We also validate the controllability of the proposed model and discuss the details of our latent manipulation on the basis of experimental results of multi-label manipulation.  相似文献   
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