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131.
Plants of the genus Wikstroemia are used in Chinese traditional medicine to treat inflammatory diseases, such as arthritis, bronchitis, and pneumonia. The present study was designed to determine whether Wikstroemia ganpi (Siebold and Zucc.) Maxim. offers a potential means of treating 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD) in mice. Symptoms such as redness, edema, and keratinization in AD mice induced by DNCB were alleviated by the co-application of an ethanolic extract of W. ganpi for 2 weeks. The severity of skin barrier function damage was evaluated by measuring TEWL (transepidermal water loss). TEWLs of DNCB sensitized mouse dorsal skin were reduced by the application of a W. ganpi ethanolic extract, and skin hydration was increased. In addition, the infiltration of inflammatory cells into the dermis was significantly reduced, as were blood levels of IgE and IL-4, which play an important role in the expression of AD. The results of this experiment suggest that W. ganpi is a potential therapeutic agent for AD.  相似文献   
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133.
We report a facile way of preparing microfluidic channels filled with electrospun functional fibers. Patterned elastic molds were in tight contact with electrospun fiber mats without any leak of the analyte solution. As an example of the simple devices, we demonstrated a microfluidic protein chip selectively purifying histidine‐tagged proteins. Highly mesoporous nitrilotriacetic acid‐functionalized polystyrene (PS‐NTA) fibers were produced by taking advantage of interpenetrating phase separation between PS and PEO during electrospinning. The specific interaction of Ni‐complexed PS‐NTA fibers with histidine enabled us to immobilize only target proteins from highly heterogeneous protein mixtures. The easy process to fabricate functionalized microchannels combined with the high production throughput from electrospinning may greatly contribute to chip‐based chromatographic and bioanalytical devices. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011  相似文献   
134.
Biosilicification in diatoms is achieved by specific interactions between silaffins, composed of polypeptides and long-chain polyamines, and silicic acid derivatives. The polycondensation of silicic acids is reported to be catalyzed by the long-chain polyamines that mainly contain tertiary N-methylpropyleneimine moieties. In this report, we utilized a tertiary amine-containing polymer, poly(2-(dimethylamino)ethyl methacrylate) (poly(DMAEMA)), as a surface-grafted, biomimetic counterpart of the long-chain polyamines in silaffins and demonstrated that the surface-initiated polycondensation of silicic acids, leading to the formation of silica thin films, proceeded smoothly on surfaces presenting poly(DMAEMA), where poly(DMAEMA) was grown from gold surfaces by surface-initiated, atom transfer radical polymerization. The formed silica film was characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy, and scanning electron microscopy.  相似文献   
135.
To elucidate the genes responsible for constitutive human skin color, we measured the extent of skin pigmentation in the buttock, representative of lifelong non-sun-exposed skin, and conducted a gene mapping study on skin color in an isolated Mongolian population composed of 344 individuals from 59 families who lived in Dashbalbar, Mongolia. The heritability of constitutive skin color was 0.82, indicating significant genetic association on this trait. Through the linkage analysis using 1,039 short tandem repeat (STR) microsatellite markers, we identified a novel genomic region regulating constitutive skin color on 11q24.2 with an logarithm of odds (LOD) score of 3.39. In addition, we also found other candidate regions on 17q23.2, 6q25.1, and 13q33.2 (LOD ≥ 2). Family-based association tests on these regions with suggestive linkage peaks revealed ten and two significant single nucleotide polymorphisms (SNPs) on the linkage regions of chromosome 11 and 17, respectively. We were able to discover four possible candidate genes that would be implicated to regulate human skin color: ETS1, UBASH3B, ASAM, and CLTC.  相似文献   
136.
For minimizing systemic experimental variation in the analysis of antibody array data, we developed a novel median-centered/IgM-tagged-internal standard (TIS) assay normalization using median-centering and TIS assay-based determination of serum IgM concentrations. We evaluated five normalization methods by analyzing correlation coefficients and coefficients of variation for six serum proteins using human serum samples from normal controls (n = 25) and patients with liver cirrhosis (n = 25) or hepatocellular carcinoma (HCC; n = 29). Median-centered normalization improved correlation coefficients, while IgM-based normalizations improved coefficients of variation. The TIS assay was more efficient, economical, and reproducible for determining IgM concentrations than enzyme-linked immunosorbent assay. Additionally, we normalized antibody array data for six serum proteins using the median-centered/IgM-TIS assay, and evaluated serum biomarkers through distribution analysis of normalized fluorescence intensities and receiver operating characteristic analyses for the diagnosis of liver cirrhosis and HCC. Apolipoprotein A-1 and a combination of alpha-fetoprotein and C-reactive protein were determined to be potential serological biomarkers for liver cirrhosis and HCC, respectively. Thus, median-centered/IgM-TIS assay normalization is a useful approach for analyzing antibody array data and evaluating serological biomarkers for the diagnosis of liver disease or cancers.  相似文献   
137.
An electric arc melter used for waste treatment processing is numerically studied. The effects of different plasma working gases are studied by using a laboratory scale test reactor. A two-dimensional finite difference approximation is used to solve the set of governing equations. The Navier-Stokes equations coupled with the combined Maxwell's equation for the electromagnetic fields is used to obtain the temperature and flow fields in the are melter. It is found that the energy efficiency of the air plasma is lower than that of an argon plasma. However, the melted soil volumes are larger using the air plasma than those using the argon plasma. The overall energy efficiency increases cis the gap between the cathode and the soil surface decreases. More uniform gas temperatures are found for the air plasma than that for the argon plasma. Result obtained from the laboratory-scale are melter is used as an input of the energy absorbed into the soil for the USBM arc melter simulation. Results show a maximum temperature of 2195 K at the center of the heat generation and a molten soil exit temperature of 1600 K.  相似文献   
138.
Control banding (CB) strategies offer simplified processes for controlling worker exposures in the absence of firm toxicological and exposure information. The nanotechnology industry is an excellent candidate for applying such strategies with overwhelming uncertainties of work-related health risks posed by nanomaterials. A recent survey shows that a majority of nanomaterial producers are not performing a basic risk assessment of their product in use. The CB Nanotool, used internationally, was developed to conduct qualitative risk assessments to control nanoparticle exposures. Nanotoxicology experts have requested standardization of toxicological parameters to ensure better utility and consistency of research. Such standardization would fit well in the CB Nanotool’s severity and probability risk matrix, therefore enhancing the protection of nanotechnology industry workers. This article further evaluates the CB Nanotool for structure, weighting of risk factors, and utility for exposure mitigation, and suggests improvements for the CB Nanotool and the research needed to bolster its effectiveness.  相似文献   
139.
Ni/NiO core/shell nanoparticles having high affinity with polyhistidine were synthesized by decomposition of a Ni surfactant complex followed by air oxidation. Ni/NiO nanoparticles showed selective and efficient binding to histidine-tagged proteins and easy separation by using a magnet. These provided a more convenient way to efficient purification of histidine-tagged proteins compared with the conventional Ni-NTA complex-bound resins and microbeads.  相似文献   
140.
Simultaneous determination of putrescine, cadaverine, spermidine, spermine, N1-acetylputrescine, N1-acetylcadaverine, N1-acetylspermidine, N8-acetylspermidine and N1-acetylspermine in aqueous samples was achieved as their N-ethoxycarbonyl-N-pentafluoropropionyl derivatives by gas chromatography-mass spectrometry (GC-MS) in selected ion monitoring (SIM) mode. The overall GC-SIM-MS method was linear (r ≥ 0.9987), repetitive (% relative standard deviation = 1.3-6.4), and accurate (% relative error = −2.1-8.6). As compared to normal subjects, the levels of putrescine, N1-acetylspermine and spermine were significantly elevated while the levels of N1-acetylputrescine, N1-acetylcadaverine and N1-acetylspermidine were markedly reduced in all four Alzheimer's disease (AD) patients. When star symbol plotting was applied to the normalized levels of nine polyamines relative to the corresponding normal mean values, each star pattern of the AD patients was deformed, thus being readily distinguishable from the nonagon shape of the normal group average.  相似文献   
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