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61.
Weirong Fang Rui Zhang Lan Sha Peng Lv Erxin Shang Dan Han Jie Wei Xiaohan Geng Qichuan Yang Yunman Li 《Journal of neurochemistry》2014,128(5):662-671
The blood–brain barrier (BBB) greatly limits the efficacy of many neuroprotective drugs' delivery to the brain, so improving drug penetration through the BBB has been an important focus of research. Here we report that platelet activating factor (PAF) transiently opened BBB and facilitated neuroprotectant edaravone penetration into the brain. Intravenous infusion with PAF induced a transient BBB opening in rats, reflected by increased Evans blue leakage and mild edema formation, which ceased within 6 h. Furthermore, rat regional cerebral blood flow (rCBF) declined acutely during PAF infusion, but recovered slowly. More importantly, this transient BBB opening significantly increased the penetration of edaravone into the brain, evidenced by increased edaravone concentrations in tissue interstitial fluid collected by microdialysis and analyzed by Ultra‐performance liquid chromatograph combined with a hybrid quadrupole time‐of‐flight mass spectrometer (UPLC‐MS/MS). Similarly, incubation of rat brain microvessel endothelial cells monolayer with 1 μM PAF for 1 h significantly increased monolayer permeability to 125I‐albumin, which recovered 1 h after PAF elimination. However, PAF incubation with rat brain microvessel endothelial cells for 1 h did not cause detectable cytotoxicity, and did not regulate intercellular adhesion molecule‐1, matrix‐metalloproteinase‐9 and P‐glycoprotein expression. In conclusion, PAF could induce transient and reversible BBB opening through abrupt rCBF decline, which significantly improved edaravone penetration into the brain.
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63.
Neurochemical Research - Postoperative cognitive dysfunction (POCD) is a common complication induced by anesthesia or surgery, which affects the concentration, cognition and memory of patients.... 相似文献
64.
Washing is a standard step for enzyme‐linked immunosorbent assays (ELISA) performed on a paper‐based chip, in which nonspecific‐binding antibodies and antigens should be removed completely from the paper surface. In this study, a novel three‐dimensional (3D) washing strategy using a heating ring‐oven was carried out on a paper‐based chip. Compared with a plane washing mode by a ring‐oven, this 3D washing strategy obtained a lower background, as gravity played an important role in the washing step. The paper‐based chip was placed on a 3D plastic holder and the waste area was connected to a heating ring. Use of a heating waste area meant that the nonspecific‐binding protein was continuously carried to the waste area through gravity and capillary action. The angle between the plastic holder and the ring plane was carefully selected. The effect of washing on different parts of the detection area was investigated by upconversion fluorescence and chemiluminescence (CL). This novel 3D washing strategy was performed for carcinoembryonic antigen detection through CL and a lower detection limit of 2 pg ml?1 was obtained. This approach provides an effective washing strategy to remove nonspecific‐binding antibody from a paper‐based immunodevice. 相似文献
65.
Specific inherent optical quantities of complex turbid inland waters, from the perspective of water classification 总被引:1,自引:0,他引:1
Sun D Li Y Wang Q Le C Lv H Huang C Gong S 《Photochemical & photobiological sciences》2012,11(8):1299-1312
For optically complex turbid productive waters, the optical behavior of suspended particles is the keynote of characterizing the unordered variations of inherent optical properties (IOPs). Multiple bio-optical measurements and sampling of optically active substances were performed in Lake Taihu, Lake Chaohu, and Lake Dianchi, and Three Gorges reservoir of China, in 2008, 2009, and 2010. On the basis of obtaining adequate observation data, we developed an improved and robust water classification approach, by which complex water conditions were divided into three types, i.e., Type 1 (Normalized Trough Depth at 675 nm, hereafter NTD675, ≥0.092), Type 2 (0 < NTD675 < 0.092), and Type 3 (NTD675 ≤ 0). Furthermore, the specific inherent optical quantities for suspended particles, including the specific absorption coefficient of non-algal particles (a*(nap)), the specific absorption coefficient of phytoplankton (a*(ph)), and the specific scattering coefficient of the suspended particles (b*(p)), were determined for the three classified types of waters. The validation results showed that our proposed values for these specific inherent optical quantities presented relatively high predictive accuracies, with most mean absolute percentage errors (MAPE) near 30%, and more importantly, performed much better than that of non-classified waters. Additionally, relative contributions of phytoplankton and non-algal particles to the total particulate absorption and scattering, as well as the spectra, were also analyzed, and the differences among the three classified types of waters were clarified. Overall, the results obtained in this study provide us with new knowledge for understanding complex varied inherent optical properties of highly turbid productive waters. 相似文献
66.
The silk egg case and orb web of spiders are elaborate structures that are assembled from a number of components. We analysed
the structure, the amino acid and fibre compositions, and the tensile properties of the silk fibres of the egg case of Nephila clavata. SEM shows that the outer and inner covers of the egg case consist of thick, medium and thin silk fibres. The silk fibres
of the outer cover of the egg case are probably produced by the major and minor ampullate glands. The silk fibres of the inner
cover of the egg case from cylindrical glands appears to be distinct from the silk fibres of the major ampullate glands based
on their micro-morphology, mole percent amino acid composition and types, and tensile behaviour and properties. Collectively,
our investigations show that N. clavata uses silk fibres from relatively few glands in varying combinations to achieve different physical and chemical properties
(e.g., color, diameter, morphology and amino acid composition) and functional and mechanical properties in the different layers
of the egg case. 相似文献
67.
Impacts of cell surface characteristics on population dynamics in a sequencing batch yeast reactor treating vegetable oil-containing wastewater 总被引:1,自引:0,他引:1
Ten yeast strains acquired from different sources and capable of utilizing vegetable oil or related compounds (fatty acid
or oleic acid) as sole carbon sources were inoculated into a sequencing batch reactor (SBR) for the treatment of high-strength
vegetable oil-containing wastewater. The SBR system stably removed >89% of chemical oxygen demand (COD) and >99% of oil when
fed with wastewater containing 15 g/L COD and 10 g/L oil in average. Denaturing gradient gel electrophoresis of polymerase
chain reaction-amplified 26S rRNA genes showed that among the ten yeast strains, only Candida lipolytica, Candida tropicalis, and Candida halophila were dominant in the system. To elucidate the major factors affecting the selection of yeast strains in the SBR system, the
three dominant strains were compared with two non-dominant strains in terms of COD removal performance, biomass yield, cell
settleability, cell flocculation ability, cell emulsification ability, and surface hydrophobicity. Results showed that hydrophobicity
and emulsification ability of yeast cells were the two most important factors determining the selection of yeast strains in
the treatment of high-strength oil-containing wastewater. 相似文献
68.
脑中风是严重危害我国中老年人身体健康的主要疾病之一,对中风相关基因单核苷酸多态性位点在人群中分布情况的研究将有助于深入认识中风发病机制及提高防治能力。该研究用寡核苷酸芯片方法检测了8个多态性位点与中风易感性之间的关联。结果发现:寡核苷酸芯片技术作为一种很好的基因分型方法,具有高通量、平行性、微量化、自动化和快速灵敏等的特点,适用于大规模基因分型平台的建立;实验初步发现与中风易感性相关的有血管紧张素原(AGT)基因M235T(OR=3.437,CI=1.211,9.709),载脂蛋白E(APOE)基因cys158arg (OR=9.434,1.686-83.3),亚甲基四氢叶酸还原酶(MTHFR)基因C677T(OR=2.591,1.002-6.711),血管紧张素ⅡⅠ型受体(AT1R)基因A1166C(OR=0.213,0.057-0.799)。 相似文献
69.
70.
百合不定芽的快速诱导 总被引:1,自引:0,他引:1
为获得麝香百合组织培养最优外植体及探讨蔗糖、6-BA和NAA的最佳用量,本文以MS固体培养基为基础培养基,通过4因素3水平(L9 (34)) 3次重复正交试验,研究不同花器官及不同浓度的蔗糖、6-BA (6 苄基嘌呤)和NAA (α-萘乙酸)对麝香百合组织培养诱导不定芽的影响.结果表明,花托为诱导不定芽最优外植体,诱导不定芽最佳培养基为MS+6-BA 1.0 mg/L+NAA 0.3 mg/L+蔗糖90 g/L.同时经过分析,可以判断本试验中设计的4个试验因素对百合组培的影响程度依次为外植体>蔗糖>奈乙酸和6-苄氨基嘌呤.本研究结果将为百合优良品种的生产提供重要的技术支撑和资源保证. 相似文献