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71.
“Idiopathic” is the most common category of uveitis, representing cases in which a specific diagnosis has not been established despite work-up. Sarcoidosis is a systemic granulomatous disorder affecting multiple organs including the lungs, skin, kidneys, and eyes. We used microRNA (miRNA) microarrays to investigate serum miRNA profiles of patients with ocular sarcoidosis as diagnosed by specific criteria (diagnosed ocular sarcoidosis), and patients with idiopathic uveitis characterized by ocular manifestations of sarcoidosis (suspected ocular sarcoidosis). Principal component analysis (PCA) and hierarchical clustering showed that serum miRNA profiles of diagnosed ocular sarcoidosis and suspected ocular sarcoidosis were both clearly distinguishable from healthy controls. Furthermore, comparative analysis of the miRNA profiles showed highly similar patterns between diagnosed ocular sarcoidosis and suspected ocular sarcoidosis. Pathway analysis revealed common pathways were involved in the two groups, including those of WNT signaling and TGF-beta signaling. Our study demonstrated a high overlap of differentially expressed serum miRNAs in patients with diagnosed ocular sarcoidosis and suspected ocular sarcoidosis, suggesting that these groups share a similar underlying pathology and may represent possible variants of the disease. Characterization of serum miRNA profiles may provide an opportunity for earlier diagnosis and treatment, and may inform more accurate clinical prognosis in patients with an ocular sarcoidosis phenotype.  相似文献   
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73.
Cage aquaculture is expanding on African inland waters and has potential to close the fish supply deficit in the region and provide other social benefits such as employment and income. However, if not appropriately guided and regulated, cage aquaculture could become unsustainable, causing conflicts with other water uses, environmental degradation and economic losses to aquaculture enterprises. To enhance sustainability of cage aquaculture on the African inland waters, we developed an inventory of cage aquaculture installations and used it to investigate the distribution and magnitude of cage aquaculture and adherence to best practices for sustainable aquaculture. Our results show evidence of spatial expansion of cage aquaculture on the African inland waters, of varying magnitude across and within water bodies and partial adherence to best practices. Cage aquaculture was confirmed on 18 water bodies which together share 263 installations with more than 20,000 cages. Lakes Victoria, Kariba, Volta and River Volta host 82.9% of cage aquaculture installations on the African inland waters and are major areas for cage aquaculture. Contrary to best practices, evidence shows cage aquaculture installations entirely or in close proximity to protected areas, in eutrophic and hypertrophic waters, shallow water bodies and sites (≥5 m average depth) and close to the shoreline. Cage aquaculture is qualified as an additional stressor to the African inland waters and because it is expected to continue expanding, adherence to best practices should be promoted for sustainability.  相似文献   
74.
The conventional two-dimensional (2D) culture is available as an in vitro experimental model. However, the culture system reportedly does not recapitulate the in vivo cancer microenvironment. We recently developed a tissueoid cell culture system using Cellbed, which resembles the loose connective tissue in living organisms. The present study performed 2D and three-dimensional (3D) culture using prostate and bladder cancer cell lines and a comprehensive metabolome analysis. Compared to 3D, the 2D culture had significantly lower levels of most metabolites. The 3D culture system did not impair mitochondrial function in the cancer cells and produce energy through the mitochondria simultaneously with aerobic glycolysis. Conversely, ATP production, biomass (nucleotides, amino acids, lipids and NADPH) synthesis and redox balance maintenance were conducted in 3D culture. In contrast, in 2D culture, biomass production was delayed due to the suppression of metabolic activity. The 3D metabolome analysis using the tissueoid cell culture system capable of in vivo cancer cell culture yielded results consistent with previously reported cancer metabolism theories. This system is expected to be an essential experimental tool in a wide range of cancer research fields, especially in preclinical stages while transitioning from in vitro to in vivo.  相似文献   
75.
A method was developed to enable users of video sharing websites to easily retrieve video scenes relevant to their interests. The system analyzes both text and non-text aspects of a user’s comment and then retrieves and displays relevant scenes along with attached comments. The text analysis works in tandem with non-text features, namely, the selected area and temporal duration associated with user comments. In this way, our system supports a better-organized retrieval of scenes that have been commented on with a higher degree of relevancy than conventional methods, such as using matching keywords. We describe our method and the relation between the scenes and discuss a prototype system.  相似文献   
76.
Mutagenesis studies on glucose oxidases (GOxs) were conducted to construct GOxs with reduced oxidase activity and increased dehydrogenase activity. We focused on two representative GOxs, of which crystal structures have already been reported—Penicillium amagasakiense GOx (PDB ID; 1gpe) and Aspergillus niger GOx (PDB ID; 1cf3). We constructed oxygen-interacting structural models for GOxs, and predicted the residues responsible for oxidative half reaction with oxygen on the basis of the crystal structure of cholesterol oxidase as well as on the fact that both enzymes are members of the glucose/methanol/choline (GMC) oxidoreductase family. Rational amino acid substitution resulted in the construction of an engineered GOx with drastically decreased oxidase activity and increased dehydrogenase activity, which was higher than that of the wild-type enzyme. As a result, the dehydrogenase/oxidase ratio of the engineered enzyme was more than 11-fold greater than that of the wild-type enzyme. These results indicate that alteration of the dehydrogenase/oxidase activity ratio of GOxs is possible by introducing a mutation into the putative functional residues responsible for oxidative half reaction with oxygen of these enzymes, resulting in a further increased dehydrogenase activity. This is the first study reporting the alteration of GOx electron acceptor preference from oxygen to an artificial electron acceptor.  相似文献   
77.
Polyamide@Polyaniline powders of core‐shell structure are known to have reduced conduction thresholds useful to maintain the mechanical and optical properties of the matrix. However, difficulties emerge at the synthesis stage, where dissolving the matrix without damaging the core‐shell particles becomes a challenge. The present solution avoids using solvents. Conductive polymer films containing solid Polyamide@Polyaniline particles are elaborated by UV photoreticulation of a liquid polyisoprene serving as a matrix. The conductive powders are obtained by in‐situ polymerization of aniline in presence of polyamide 12 (PA12) at room temperature using Dodecyl benzene sulfonic doping acid and Ammonium persulfate oxidant. Obtained films exhibit low percolation threshold compared to those containing pure solid polyaniline (PANI) particles even more conductive. This threshold is shown to be about 1.5 wt % of PANI. Films show good electrical conductivity and thermal stability up to 200°C allowing their use as antistatic polymer films for high temperatures. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39833.  相似文献   
78.
We have developed a novel strategy for the direct substitution of benzyl alcohols with anthranilic acids using water‐soluble copper catalysts through a radical pathway in water, which offers efficient and environmentally friendly N‐, S‐, and C‐benzylations under neutral conditions. Radical scavengers strongly inhibited the benzylation. Radical clock experiments using α‐cyclopropylbenzyl alcohol were conducted to observe the rapid isomerization of the cyclopropylmethyl radical to the allylmethyl radical. Hammett plots could be fitted to a two‐parameter Hammett relationship containing both radical and polar contributions [log (kX/kH)=−1.24 σ.–0.38 σ, R2=0.99]. The relative parameter ρ./ρ of 3.3 suggested that these reactions involved a strong radical character with minor polar influence at the transition state.

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79.
We demonstrate a borrowing hydrogen methodology using the unique reactivity of the π‐benzylpalladium system in water, which offers an efficient and environmentally friendly N‐monobenzylation of electron‐deficient anilines or 2‐aminopyridine with non‐activated benzylic alcohols under neutral conditions. The crossover experiment using benzyl‐α,α‐d2 alcohol and 3‐methylbenzyl alcohol afforded H/D scrambling products, suggesting that the borrowing hydrogen pathway occurred in our catalytic system. Our simple protocol can accomplish a gram scale reaction of 2‐aminobenzonitrile (76 % isolated yield), and is performed with the use of only 1 mol % Pd(OAc)2 and 2 mol % TPPMS without other additives in water.

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80.
The aminoalcohol dehydrogenase (AADH) of Rhodococcus erythropolis MAK154, which can be used as a catalyst for the stereoselective reduction of (S)-1-phenyl-1-keto-2-methylaminopropane to d-pseudoephedrine (dPE), is inhibited by the accumulation of dPE in the reaction mixture, limiting the yield of dPE. To improve this weak point of the enzyme, random mutations were introduced into aadh, and a mutant enzyme library was constructed. The mutant library was screened with a color detectable high-throughput screening method to obtain the evolved enzymes showing the activity in the presence of a high concentration of dPE. Two mutant enzymes showed higher tolerability to dPE than the wild type enzyme. Each of these enzymes had a single amino acid substitution in a different position (G73S and S214R), and a third mutant enzyme carrying both of these amino acid substitutions was constructed. Escherichia coli transformant cells, which express mutant AADHs, showed activity in the presence of 100mg/ml dPE. A kinetic parameter analysis of the wild type and mutant enzymes was carried out. As compared with the wild type enzyme, the mutant enzymes carrying the S214R amino acid substitution or both the S214R and G73S substitutions showed higher k(cat) values, and the mutant enzymes carrying the G73S amino acid substitution or both the G73S and S214R substitutions showed higher K(m) values. These results suggest that the Ser214 residue plays an important role in enzyme activity, and that the Gly73 residue participates in enzyme-substrate binding.  相似文献   
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