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21.
Yucheng Liu Shulin Liu Zhifang Zhang Lingbin Ni Xingming Chen Yunxia Ge Guoan Zhou Zhixi Tian 《中国科学:生命科学英文版》2022,65(9):1898-1901
<正>Dear Editor,Soybean(Glycine max [L.] Merr.) provides more than half of the oilseeds and more than a quarter of protein worldwide. It is estimated that the production of soybean has to be doubled by 2050 to meet the needs of the rapidly increasing consumption of soybean seeds along with a continuously increasing population(Ray et al., 2013). As such, development of a genotyping platform with high throughput, high efficiency and high precision but low-cost is urgently needed to accelerate... 相似文献
22.
Xiaowei Xu Sulin Ren Xiaoxiao Chen Jun Ge Zhenxing Xu Hongying Huang Honglin Sun Yue Gu Tong Zhou Jianqiang Li Hanmei Xu 《Virologica Sinica》2014,(6)
Despite the long availability of a traditional prophylactic vaccine containing the HBV surface antigen(HBsA g) and aluminum adjuvant, nearly 10% of the population remains unable to generate an effective immune response. Previous studies have indicated that hepatitis B virus(HBV) PreS 2-S is abundant in T/B cell epitopes, which induces a stronger immune response than HBsA g, particularly in terms of cytotoxic T lymphocyte(CTL) reaction. In the current study, the HBV PreS 2-S gene encoding an extra26 amino acids(PreS 2 C-terminus) located at the N-terminus of HBsA g was cloned into the pV CH1300 expression vector. Pre S2-S expressed in the methylotrophic yeast, Hansenula polymorpha, was produced at a yield of up to 250 mg/L. Subsequent purification steps involved hydrophobic adsorption to colloidal silica, ion-exchange chromatography and density ultracentrifugation. The final product was obtained with a total yield of ~15% and purity of ~99%. In keeping with previous studies, ~22 nm viruslike particles were detected using electron microscopy. The generated PreS 2-S antigen will be further studied for efficacy and safty in animals. 相似文献
23.
Ying-Jin Yuan Jing-Chuan Li Zhi-Qiang Ge Jin-Chuan Wu 《Journal of Molecular Catalysis .B, Enzymatic》2002,18(4-6):251-260
Generation of reactive oxygen species (ROS) induced by Ce4+ in suspension cultures of Taxus cuspidata was investigated. The burst of superoxide anions (O2√−) occurred rapidly after the addition of Ce4+ and reached maximum at 4.3 h, while the total level of the cellular reactive oxygen species maintained unchanged. The intracellular superoxide dismutase (SOD) and catalase (CAT) were activated while the intra/extracellular peroxidases (PODs) were inhibited accompanying the O2√− burst. The pretreatment of the suspension cultures with diphenylene iodonium (DPI), a suicide inhibitor of the NADPH oxidase, blocked the O2√− burst, inhibiting the cell apoptosis and taxol production induced by Ce4+. These results show that NADPH oxidase played a key role in O2√− burst and O2√− served as a mediator of Ce4+ for cell apoptosis and taxol production. The pretreatments of the suspension cultures with anthracene-9-carboxylate, an ion-channel blocker, nifedipine, a Ca2+-channel blocker, neomycin, a phospholipase C (PLC) inhibitor, or suramin, a G-protein inhibitor, decreased O2√− burst induced by Ce4+. It is thus inferred that Ce4+-induced O2√− burst, which mediated cell apoptosis and taxol production by activating the ion-channels, PLC, G-proteins and NADPH oxidase. 相似文献
24.
隐甲藻深层培养产生二十碳五烯酸的研究 总被引:5,自引:0,他引:5
二十碳五烯酸 (C2 0 :5 ,Eicosapentaenoicacid ,简称EPA)是一种重要的ω 3系列人体必需多不饱和脂肪酸 (Polyun saturatedfattyacids,PUFA) [1~ 2 ] 。自从Dyerberge等人报道了二十碳五烯酸对防止和治疗血栓、关节硬化、抗炎症、抗癌、促进脑组织发育等方面具有明显效果以来 ,人们对它的营养和医药价值及生产方法进行了广泛的研究[3~ 6] 。目前 ,二十碳五烯酸主要来源于深海鱼油 ,但其产量不稳定 ,纯化工艺复杂且含有难以消除的鱼腥味 ,难以满足市场的需求。由于二十碳五… 相似文献
25.
Yang Liu Limei Ren Lingmiao Ge Qingxin Cui Xiaofang Cao Yuanyuan Hou Fang Bai Gang Bai 《Biotechnology letters》2014,36(8):1675-1680
KGLP-1, a 31-amino acid glucagon-like peptide-1 (GLP-1) analogue, has a great therapeutic potential for anti-diabetes. In this work, a strategy for expression and purification of functional KGLP-1 peptide has been established. KGLP-1 cDNA was fused with glutathione S-transferase (GST), with an enterokinase cleavage site in the fusion junction. The recombinant fusion protein GST–KGLP-1 was affinity purified via the GST-tag, and then digested with enterokinase. The resulting GST part as well as the enzymes were eliminated by ultra-filtration followed by size exclusion chromatograph. The yield of purified KGLP-1 was approximately 12.1 mg/L, with purity of 96.18 %. The recombinant KGLP-1 was shown to have similar bioactivity as native GLP-1 when evaluated in a Chinese hamster ovary cell line expressing a GLP-1 receptor-egfp reporter gene. 相似文献
26.
The inhibition of lung cancer cell growth by intracellular immunization with LC—1 ScFv 总被引:2,自引:0,他引:2
INTRODUCTIONLung cancer remains the leading cause of can-cer mortaIity in the world, accounting for more thanone sixth of cancer deaths in the world[1]. Antibod-ies have been proved to be a powerful tool fOr thestudy of 1ung cancer. A monoclonal IgM antibody,LC-1, was obtained in our laboratory. It can reactat a high rate with all four pathological types of lungcancers, including lung adenocarcinoma, 1ung squamous carcinoma, large cell lung cancer and smaIlcell lung cancert but not wit… 相似文献
27.
Guan S Ma S Zhu Y Ge R Wang Q Wang JH 《Biochemical and biophysical research communications》2006,345(1):175-180
Cerebellum is involved in the motion coordination and working memory, to which the programming of sequential spikes at Purkinje cells is essential. It is not clear about the intrinsic mechanisms underlying spike capacity and timing precision as well as their postnatal maturation. We investigated the programming and intrinsic property of sequential spikes at Purkinje neurons during postnatal development by whole-cell recording in cerebellar slices. Cerebellar Purkinje neurons demonstrate the increasing of spike capacity and timing precision, as well as the lowering of refractory periods and threshold potentials during the postnatal maturation. In addition, the correlation between spike parameters and intrinsic properties converts to be more linear. This postnatal plasticity of neuronal intrinsic properties improves the timing precision and capacity of spike programming at cerebellar Purkinje neurons. 相似文献
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Tong tong Ge Xiao Xiao Yao Feng Lian Zhao Xiao han Zou Wei Yang Ran Ji Cui Bing jin Li 《Journal of cellular and molecular medicine》2020,24(8):4524-4532
Leptin is well acknowledged as an anorexigenic hormone that plays an important role in feeding control. Hypothalamic GABA system plays a significant role in leptin regulation on feeding and metabolism control. However, the pharmacological relationship of leptin and GABA receptor is still obscure. Therefore, we investigated the effect of leptin or combined with baclofen on the food intake in fasted mice. We detected the changes in hypothalamic c‐Fos expression, hypothalamic TH, POMC and GAD67 expression, plasma insulin, POMC and GABA levels to demonstrate the mechanisms. We found that leptin inhibit fasting‐induced increased food intake and activated hypothalamic neurons. The inhibitory effect on food intake induced by leptin in fasted mice can be reversed by pretreatment with baclofen. Baclofen reversed leptin's inhibition on c‐Fos expression of PAMM in fasted mice. Therefore, these results indicate that leptin might inhibit fasting‐triggered activation of PVN neurons via presynaptic GABA synaptic functions which might be partially blocked by pharmacological activating GABA‐B. Our findings identify the role of leptin in the regulation of food intake. 相似文献