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991.
Haiqiang Lan Tao Huang Jiangwei Xiao Zhaohong Liao Jun Ouyang Jianghui Dong Cory J. Xian Jijie Hu Liping Wang Yu Ke Hua Liao 《Journal of cellular and molecular medicine》2021,25(1):561-574
pH-magnetic dual-responsive nanocomposites have been widely used in drug delivery and gene therapy. Recently, a polypseudorotaxane functionalized magnetic nanoparticle (MNP) was developed by synthesizing the magnetic nanoparticles with cyclodextrin (CD) molecules (CDMNP) via polyethylene glycol (PEG) (CDMNP-PEG-CD). The purpose of this study was to explore the antigenicity and immunogenicity of the nanoparticles in vivo prior to their further application explorations. Here, nanoparticles were assessed in vivo for retention, bio-distribution and immuno-reactivity. The results showed that, once administered intravenously, CDMNP-PEG-CD induced a temporary blood monocyte response and was cleared effectively from the body through the urine system in mice. The introduction of β-CD and PEG/β-CD polypseudorotaxane on SiO2 magnetic nanoparticles (SOMNP) limited particle intramuscular dispersion after being injected into mouse gastrocnemius muscle (GN), which led to the prolonged local inflammation and muscle toxicity by CDMNP and CDMNP-PEG-CD. In addition, T cells were found to be more susceptible for β-CD–modified CDMNP; however, polypseudorotaxane modification partially attenuated β-CD–induced T cell response in the implanted muscle. Our results suggested that CDMNP-PEG-CD nanoparticles or the decomposition components have potential to prime antigen-presenting cells and to break the muscle autoimmune tolerance. 相似文献
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Liu Guilin Zhang Zhongyang Shao Jianbo Xi Xi Dong Weifu Dong Yuming Chen Guoqing Chen Liping Chen Rulong 《Plasmonics (Norwell, Mass.)》2019,14(6):1405-1410
Plasmonics - Anisotropy photoresponse can be effectively achieved based on gradient organic heterojunction. However, the gradient heterojunction has yet been studied due to the complicated process... 相似文献
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Chen Yue Wang Yunzhu Lyu Ping Chen Liping Shen Chenjia Sun Chongbo 《Journal of plant research》2019,132(3):419-429
Journal of Plant Research - Dendrobium officinale is a traditional medicinal herb with a variety of bioactive components. Alkaloid is one of the major active ingredients of Dendrobium plants, and... 相似文献
994.
Assessing natural infection with Zika virus in the southern house mosquito,Culex quinquefasciatus,during 2016 in Puerto Rico 下载免费PDF全文
D. A. YEE R. DEJESUS‐CRESPO F. F. HUNTER F. BAI 《Medical and veterinary entomology》2018,32(2):255-258
The epidemic of Zika in the Western hemisphere has led to intense investigations of all species important in the transmission of Zika virus (ZikV), including putative mosquito vectors. Although evidence points to Stegomyia (= Aedes) (Diptera: Culicidae) mosquitoes as the primary vectors in nature among humans, there remains the possibility that other common mosquito species may be implicated in the rapid spread of the virus. Herein, field‐caught Culex quinquefasciatus (Diptera: Culicidae) collected during June 2016 in different neighbourhoods in San Juan, Puerto Rico were examined for the presence of natural infection with ZikV. Stegomyia aegypti (= Aedes aegypti) from the same locations were also analysed. None of the Cx. quinquefasciatus tested showed natural infection for ZikV, whereas S. aegypti tested positive at seven sites. The present results suggest that Cx. quinquefasciatus was not involved in the transmission of ZikV in San Juan, Puerto Rico in 2016. 相似文献
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Proanthocyanidins in Chinese bayberry leaves (PCBLs) were qualitatively analyzed. NMR data suggest that PCBLs are mostly composed of (epi)gallocatechin gallate units. Matrix-assisted laser desorption time-of-flight MS data indicate 95 possible prodelphinidin structures, ranging from dimers to tridecamers. Preparative normal-phase HPLC and further analysis by reverse-phase HPLC together with electrospray ionization MS enabled detection of 20 compounds, including seven newly identified compounds in Chinese bayberry leaves. The antioxidant capacity of PCBLs was evaluated by (1,1-diphenyl-2-picryl-hydrazyl), ferric-reducing antioxidant power, and oxygen radical absorption capacity assays. The EC50 of DPPH radical scavenging activities (as 50% decrease in the initial DPPH concentration) were 7.60 µg. The FRAP and ORAC values were 8859.33±978.39 and 12991.61±1553.34 µmol Trolox equivalents per gram, respectively. The results indicate the high antioxidant potency of PCBLs. 相似文献
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【目的】鉴定能够调控猪流行性腹泻病毒(porcine epidemic diarrhea virus,PEDV)复制的关键宿主蛋白。【方法】利用LC-MS/MS技术结合串联质谱标签(tandem mass tag,TMT),分析PEDV感染Vero细胞36 h后和未感染组的蛋白组学差异。鉴定筛选了114个显著差异表达蛋白,其中宿主胚胎干细胞特异性5-羟甲基胞嘧啶结合蛋白(5-hydroxymethylcytosine binding,ES cell-specific protein,HMCES)显著上调。进一步构建HMCES真核表达质粒,通过蛋白免疫印迹和实时荧光定量PCR检测过表达HMCES对PEDV复制的影响;合成针对HMCES基因的特异性si RNA,利用Western blotting和RT-q PCR检测si RNA对HMCES表达的干扰效果及HMCES被干扰后对PEDV复制的影响。【结果】过表达HMCES能显著促进PEDV在Vero细胞中复制,并且复制水平随着HMCES的剂量递增呈现剂量依赖式增加;si RNA-341下调内源性HMCES表达进而抑制PEDV复制。【结论】H... 相似文献
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