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81.
82.
Photodynamic therapy with redaporfin targets the endoplasmic reticulum and Golgi apparatus 下载免费PDF全文
Lígia C Gomes‐da‐Silva Liwei Zhao Lucillia Bezu Heng Zhou Allan Sauvat Peng Liu Sylvère Durand Marion Leduc Sylvie Souquere Friedemann Loos Laura Mondragón Baldur Sveinbjørnsson Øystein Rekdal Gaelle Boncompain Franck Perez Luis G Arnaut Oliver Kepp Guido Kroemer 《The EMBO journal》2018,37(13)
Preclinical evidence depicts the capacity of redaporfin (Redp) to act as potent photosensitizer, causing direct antineoplastic effects as well as indirect immune‐dependent destruction of malignant lesions. Here, we investigated the mechanisms through which photodynamic therapy (PDT) with redaporfin kills cancer cells. Subcellular localization and fractionation studies based on the physicochemical properties of redaporfin revealed its selective tropism for the endoplasmic reticulum (ER) and the Golgi apparatus (GA). When activated, redaporfin caused rapid reactive oxygen species‐dependent perturbation of ER/GA compartments, coupled to ER stress and an inhibition of the GA‐dependent secretory pathway. This led to a general inhibition of protein secretion by PDT‐treated cancer cells. The ER/GA play a role upstream of mitochondria in the lethal signaling pathway triggered by redaporfin‐based PDT. Pharmacological perturbation of GA function or homeostasis reduces mitochondrial permeabilization. In contrast, removal of the pro‐apoptotic multidomain proteins BAX and BAK or pretreatment with protease inhibitors reduced cell killing, yet left the GA perturbation unaffected. Altogether, these results point to the capacity of redaporfin to kill tumor cells via destroying ER/GA function. 相似文献
83.
SiO2‐Enhanced Structural Stability and Strong Adhesion with a New Binder of Konjac Glucomannan Enables Stable Cycling of Silicon Anodes for Lithium‐Ion Batteries 下载免费PDF全文
Songtao Guo Heng Li Yaqian Li Yong Han Kebei Chen Gengzhao Xu Yingjie Zhu Xianluo Hu 《Liver Transplantation》2018,8(24)
Silicon‐based anodes with high theoretical capacity have intriguing potential applications for next‐generation high‐energy lithium‐ion batteries, but suffer from huge volumetric change that causes pulverization of electrodes. Rational design and construction of effective electrode structures combined with versatile binders remain a significant challenge. Here, a unique natural binder of konjac glucomannan (KGM) is developed and an amorphous protective layer of SiO2 is fabricated on the surface of Si nanoparticles (Si@SiO2) to enhance the adhesion. Benefiting from a plethora of hydroxyl groups, the KGM binder with inherently high adhesion and superior mechanical properties provides abundant contact sites to active materials. Molecular mechanics simulations and experimental results demonstrate that the enhanced adhesion between KGM and Si@SiO2 can bond the particles tightly to form a robust electrode. In addition to bridging KGM molecules, the SiO2‐functionalized surface may serve as a buffer layer to alleviate the stresses of Si nanoparticles resulting from the volume change. The as‐fabricated KGM/Si@SiO2 electrode exhibits outstanding structural stability upon long‐term cycles. A highly reversible capacity of 1278 mAh g?1 can be achieved over 1000 cycles at a current density of 2 A g?1, and the capacity decay is as small as 0.056% per cycle. 相似文献
84.
85.
In order to genotype hybrid genomes of distant asymmetric somatic hybrids, we synthesized hybrid calli and plants via PEG-mediated
protoplast fusion between recipient tall fescue (Festuca. arundinacea Schreb.) and donor wheat (Triticum aestivum L.). Seventeen and 25 putative hybrid clones were produced from the fusion combinations I and II, each with the donor wheat
protoplast treated by UV light for 30 s and 1 min, respectively. Isozyme and RAPD profiles confirmed that ten hybrid clones
were obtained from combination I and 19 from combination II. Out of the 29 hybrids, 12 regenerated hybrid plants with tall
fescue phenotype. Composition and methylation-variation of the nuclear and cytoplasmic genomes of some hybrids, either with
or without regenerative ability, were compared by genomic in situ hybridization, restriction fragment length polymorphism,
and DNA methylation-sensitive amplification polymorphism. Our results indicated that these selected hybrids all contained
introgressed nuclear and cytoplasmic DNA as well as obvious methylation variations compared to both parents. However, there
were no differences either in nuclear/cytoplasmic DNA or methylation degree between the regenerable and non-regenerable hybrid
clones. We conclude that both regeneration complementation and genetic material balance are crucial for hybrid plant regeneration. 相似文献
86.
This study attempted to develop a 'less meiotically competent' murine model for oocyte in vitro maturation (IVM), which could more readily be extrapolated to human clinical assisted reproduction. Oocyte meiotic competence was drastically reduced upon shortening the standard duration of in vivo gonadotrophin stimulation from 48 h to 24 h, and by selecting only naked or partially naked germinal vesicle oocytes, instead of fully cumulus enclosed oocyte complexes. With such a less meiotically competent model, only porcine granulosa coculture significantly enhanced the oocyte maturation rate in vitro, whereas no significant enhancement was observed with macaque and murine granulosa coculture. Increased serum concentrations and the supplementation of gonadotrophins, follicular fluid and extracellular matrix gel within the culture medium did not enhance IVM under either cell-free or coculture conditions. Culture medium conditioned by porcine granulosa also enhanced the maturation rate, and this beneficial effect was not diminished upon freeze-thawing. Enhanced IVM in the presence of porcine granulosa coculture did not, however, translate into improved developmental competence, as assessed by in vitro fertilization and embryo culture to the blastocyst stage. 相似文献
87.
BACE蛋白的表达、纯化和活性测定 总被引:2,自引:0,他引:2
在大肠杆菌中表达、纯化并重新折叠以获得有活性的酸性蛋白水解酶 (BACE蛋白 )———一种与阿尔茨海默病 (AD)发病相关的蛋白水解酶。克隆BACE活性区的表达序列到原核表达载体 pET11a中 ,经E .coliBL2 1(DE3)表达 ,从包涵体中获取蛋白质 ,电泳鉴定后经梯度反向快速折叠法重新折叠 ,柱层析分离纯化 ,得到了表达的重组可溶性BACE蛋白 ;用高效液相色谱、质谱等方法检测其对人工合成多肽底物的水解作用 ;测定了BACE蛋白的酶促动力学常数。结果表明 ,得到的重组BACE蛋白具有水解人工合成小肽底物的活性。 相似文献
88.
目的:探讨多情景式模拟教学在护理人际沟通双语实践课的应用。方法:采用不对等对照组组间设计方法,2011级全日制护理专业本科78名学生为对照组,2012级全日制护理专业本科生72名为实验组,在相同《护理人际沟通》双语理论教学的基础上,对照组进行常规实践教学;实验组应用多情景式的模拟教学。结果:对照组实践成绩为35.02±18.44,实验组实践成绩为40.27±12.61,实验组实践课成绩高于对照组,有统计学意义(P0.05)。结论:将多情景式的模拟教学应用于《护理人际沟通》双语课程的实践教学,有助于提升英语水平,建立团队协作意识,学会合理利用沟通技巧处理不同情景中的人际矛盾,更能够提高护理人际沟通教学质量,为人际沟通课程改革提供指导。 相似文献
89.
Haidong Wei Xi Yao Lifang Yang Shiquan Wang Fan Guo Heng Zhou Giovanni Marsicano Qiang Wang Lize Xiong 《Molecular neurobiology》2014,49(1):326-336
We have previously shown that electroacupuncture (EA) pretreatment produces neuroprotective effects, which were mediated through an endocannabinoid signal transduction mechanism. Herein, we have studied the possible contribution of the phosphorylated form of glycogen synthase kinase-3β (GSK-3β) in EA pretreatment-induced neuroprotection via the cannabinoid CB1 receptor (CB1R). Focal transient cerebral ischemia was induced by middle cerebral artery occlusion in rats. Phosphorylation of GSK-3β at Ser-9 [p-GSK-3β (Ser-9)] was evaluated in the penumbra tissue following reperfusion. Infarct size and neurological score were assessed in the presence of either PI3K inhibitors or a GSK-3β inhibitor 72 h after reperfusion. Cellular apoptosis was evidenced by TUNEL staining and determination of the Bax/Bcl-2 ratio 24 h after reperfusion. The present study showed that EA pretreatment increased p-GSK-3β(Ser-9) 2 h after reperfusion in the ipsilateral penumbra. Augmented phosphorylation of GSK-3β induced similar neuroprotective effects as did EA pretreatment. By contrast, inhibition of PI3K dampened the levels of p-GSK-3β(Ser-9), and reversed not only the neuroprotective effect but also the anti-apoptotic effect following EA pretreatment. Regulation of GSK-3β by EA pretreatment was abolished following treatment with a CB1R antagonist and CB1R knockdown, whereas two CB1R agonists enhanced the phosphorylation of GSK-3β. Therefore we conclude that EA pretreatment protects against cerebral ischemia/reperfusion injury through CB1R-mediated phosphorylation of GSK-3β. 相似文献
90.
The inhibitory effects of capillarisin on cell proliferation and invasion of prostate carcinoma cells 下载免费PDF全文
Ke‐Hung Tsui Ying‐Ling Chang Pei‐Shan Yang Chen‐Pang Hou Yu‐Hsiang Lin Bing‐Wei Lin Tsui‐Hsia Feng Horng‐Heng Juang 《Cell proliferation》2018,51(2)