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991.
微生物来源的谷氨酰胺转氨酶(mTG)介导的单一定点修饰的PEG IFN-α2a(英文) 总被引:1,自引:0,他引:1
PEG修饰被认为是改善重组蛋白药物特性的最有效手段,包括增加蛋白质药物在体内的血浆半衰期,降低免疫原性和抗原性。目前典型的PEG修饰手段为将PEG连接至蛋白质的游离氨基,包括赖氨酸和N-末端,但这种连接缺乏选择性,产物为混合物,活性及工艺稳定性差,难以控制。酶法PEG化修饰能有效克服上述缺点,其中谷氨酰胺转氨酶(TGase)可以作为PEG化定点修饰用酶。文中选择重组人干扰素α2a(IFNα2a)进行酶法修饰反应,通过计算机模拟预测IFNα2a可以在第101位Gln特异性定点修饰。将IFNα2a与40 kDa的Y型PEG在微生物来源的谷氨酰胺转氨酶(mTG)催化下进行定点PEG化修饰。结果显示,mTG可以介导IFNα2a特异性位点Gln的单一定点PEG修饰,产生分子量为58 495.6 Da的PEG-Gln101-IFNα2a分子。圆二色谱结果显示,PEG-Gln101-IFNα2a与未修饰的IFNα2a具有相同的二级结构。SD大鼠药代结果显示,与IFNα2a相比,PEG-Gln101-IFNα2a能有效提高药代动力学参数,强于已上市PEGIFNα2a-PEGASYS?。 相似文献
992.
Bulliform phytoliths play an important role in researching rice origins as they can be used to distinguish between wild and domesticated rice. Rice bulliform phytoliths are characterized by numerous small shallow fish-scale decorations on the lateral side. Previous studies have shown that domesticated rice has a larger number of these decorations than wild rice and that the number of decorations ≥9 is a useful feature for identifying domesticated rice. However, this standard was established based on limited samples of modern rice plants. In this study, we analyzed soil samples from both wild and domesticated rice paddies. Results showed that, in wild rice soil samples, the proportion of bulliform phytoliths with ≥9 decorations was 17.46% ± 8.29%, while in domesticated rice soil samples, the corresponding proportion was 63.70% ± 9.22%. This suggests that the proportion of phytoliths with ≥9 decorations can be adopted as a criterion for discriminating between wild and domesticated rice in prehistoric soil. This indicator will be of significance in improving the application of fish-scale decorations to research into rice origins and the rice domestication process. 相似文献
993.
994.
Nanzhong Wu Wenjiao Yao Xiaohe Song Ge Zhang Bingjie Chen Jinhu Yang Yongbing Tang 《Liver Transplantation》2019,9(16)
Ca‐ion based devices are promising candidates for next‐generation energy storage with high performance and low cost, thanks to its multielectrons, superior kinetics, as well as abundance (2500 times lithium). Because of the lack of an appropriate combination of suitable electrode materials and electrolytes, it is unsuccessful to attain a satisfactory performance on complete Ca‐ion energy storage devices. Here, the multiion reaction strategy is defined to construct a complete Ca‐ion energy storage device and a capacitor–battery hybrid mechanism is deliberately adopted. Profiting from the elaborate design, it exhibits a high reversible capacity of 92 mAh g?1, unmatchable rate capability, and a high capacity retention of 84% over 1000 cycles under room temperature, which is the best performance of reported Ca‐based energy storage devices. 相似文献
995.
Xiaohe Yu Naijian Ge Xu Guo Shuqun Shen Jun Liang Xiaojun Huang Shaogui Wan Jingliang Xing Qichao Huang Yefa Yang 《PloS one》2014,9(4)
The epithelial cell adhesion molecule (EPCAM) is involved in the tumorigenesis and progression of many malignancies, including hepatocellular carcinoma (HCC). Single nucleotide polymorphisms (SNPs) of EPCAM have been reported to be with the risk and prognosis of several malignancies. However, the association of SNPs in EPCAM gene with the prognosis of HCC patients has never been investigated. In this study, two functional SNPs (rs1126497 and rs1421) in the EPCAM gene were selected and genotyped in a cohort of 448 unresectable Chinese HCC patients treated by TACE. The association of the two SNPs with the overall survival (OS) of patients was assessed by univariate and multivariate Cox proportional hazards model and Kaplan-Meier curve. Our data showed that there was no significant association between either SNP and OS of patients. However, in the stratified analysis, the variant-containing genotypes (WV+VV) of SNP rs1126497 exhibited a significant association with poorer OS in HCC patients who had portal vein tumor thrombus (PVTT) in multivariate analysis of Cox proportional hazard model (hazard ratio, 1.71; 95% confidence interval, 1.16–2.53, P = 0.007), and in Kaplan-Meier curve analysis (P = 0.023), comparing to those carrying wild-type genotype. Our results suggest that SNP rs1126497 in the EPCAM gene may serve as an independent prognosis biomarker for unresectable HCC patient with PVTT, which warranted further validating investigation. 相似文献
996.
Assimilate allocation by rice and carbon stabilisation in soil: effect of water management and phosphorus fertilisation 总被引:1,自引:0,他引:1
Atere Cornelius Talade Ge Tida Zhu Zhenke Liu Shoulong Huang Xizhi Shibsitova Olga Guggenberger Georg Wu Jinshui 《Plant and Soil》2019,445(1-2):153-167
Plant and Soil - Water and nutrient management influences the allocation and stabilisation of newly assimilated carbon (C) in paddy soils. This study aimed to determine the belowground allocation... 相似文献
997.
998.
Zhenhuang Ge Peibo Yuan Lingming Chen Junyi Chen Dong Shen Zhigang She Yongjun Lu 《Molecular & cellular proteomics : MCP》2022,21(5):100233
Legionella pneumophila, an environmental bacterium that parasitizes protozoa, causes Legionnaires’ disease in humans that is characterized by severe pneumonia. This bacterium adopts a distinct biphasic life cycle consisting of a nonvirulent replicative phase and a virulent transmissive phase in response to different environmental conditions. Hence, the timely and fine-tuned expression of growth and virulence factors in a life cycle–dependent manner is crucial for survival and replication. Here, we report that the completion of the biphasic life cycle and bacterial pathogenesis is greatly dependent on the protein homeostasis regulated by caseinolytic protease P (ClpP)-dependent proteolysis. We characterized the ClpP-dependent dynamic profiles of the regulatory and substrate proteins during the biphasic life cycle of L. pneumophila using proteomic approaches and discovered that ClpP-dependent proteolysis specifically and conditionally degraded the substrate proteins, thereby directly playing a regulatory role or indirectly controlling cellular events via the regulatory proteins. We further observed that ClpP-dependent proteolysis is required to monitor the abundance of fatty acid biosynthesis–related protein Lpg0102/Lpg0361/Lpg0362 and SpoT for the normal regulation of L. pneumophila differentiation. We also found that the control of the biphasic life cycle and bacterial virulence is independent. Furthermore, the ClpP-dependent proteolysis of Dot/Icm (defect in organelle trafficking/intracellular multiplication) type IVB secretion system and effector proteins at a specific phase of the life cycle is essential for bacterial pathogenesis. Therefore, our findings provide novel insights on ClpP-dependent proteolysis, which spans a broad physiological spectrum involving key metabolic pathways that regulate the transition of the biphasic life cycle and bacterial virulence of L. pneumophila, facilitating adaptation to aquatic and intracellular niches. 相似文献
999.
1000.
Yiguan Qian Yang Li Rongfei Li Tianli Yang Ruipeng Jia Yu-Zheng Ge 《Journal of cellular and molecular medicine》2021,25(22):10349-10361
Circular RNAs (circRNAs) are a novel group of endogenous RNAs with a circular structure. Growing evidence indicates that circRNAs are involved in a variety of human diseases including malignancies. CircRNA ZNF609 (circ-ZNF609), derived from the ZNF609 gene sequence, has been demonstrated to be involved in the development and progression of many diseases. circ-ZNF609 is thought to be a viable diagnostic and prognostic biomarker for several diseases and might be a new therapeutic target, but further research is needed to accelerate clinical application. Here, we review the biogenesis and function of circRNAs and the functional roles and molecular mechanism related to circ-ZNF609 in neoplasms and other diseases. 相似文献