甘露糖基转移酶Alg11是N糖基化途径中的关键酶,催化第4和第5个甘露糖(Man)残基以α-1,2连键的形式转移到底物Man3-GlcNAc2-PP-Dol生成Man5-GlcNAc2-PP-Dol,人类ALG11基因致病突变会导致相关的先天性糖基化疾病ALG11-CDG(Congenital Diso...甘露糖基转移酶Alg11是N糖基化途径中的关键酶,催化第4和第5个甘露糖(Man)残基以α-1,2连键的形式转移到底物Man3-GlcNAc2-PP-Dol生成Man5-GlcNAc2-PP-Dol,人类ALG11基因致病突变会导致相关的先天性糖基化疾病ALG11-CDG(Congenital Disorders of Glycosylation)。目前,对ALG11-CDG的研究更侧重于其临床症状,而患者Alg11突变蛋白的性质还有待探索。作者以研究ALG11-CDG突变蛋白的重组表达及活性为目的,首先在人胚胎肾细胞HEK293和酿酒酵母中分别表达了Alg11野生型及突变体蛋白,发现其表达量存在显著差异,突变体蛋白不能稳定表达。最终在大肠杆菌中成功稳定表达了野生型及ALG11-CDG相关突变蛋白,利用液质联用定量分析了蛋白质的活性,结果显示,突变蛋白的活性存在不同程度的降低,其降低程度与ALG11-CDG疾病的严重程度存在一定的相关性。上述研究结果证明:1)ALG11-CDG相关突变蛋白的不稳定有可能是造成疾病的原因之一;2)体外定量测试大肠杆菌表达的ALG11-CDG相关突变蛋白的活性可以为相应患者的疾病严重程度提供参考。展开更多
To overcome the fast or burst release of hydrophilic drugs from hydrophilic alginate-based carriers,hydrophobic molecule(vinyl acetate,VAc)was grafted on alginate(Alg),which was further used to prepare drug carriers.A...To overcome the fast or burst release of hydrophilic drugs from hydrophilic alginate-based carriers,hydrophobic molecule(vinyl acetate,VAc)was grafted on alginate(Alg),which was further used to prepare drug carriers.Amphiphilic Alg-g-PVAc hydrogel beads were firstly prepared by emulsification/internal gelation technique for the loading of bovine serum albumin(BSA).Then,chitosan was coated on the surface of beads to form novel amphiphilic Alg-g-PVAc/chitosan(Alg-g-PVAc/CS)microcapsules.The BSA-loading amphiphilic Alg-g-PVAc/chitosan(Alg-g-PVAc/CS)microcapsules display similar morphology and size to the hydrophilic alginate/chitosan(AC)microcapsules.However,the drug loading and loading efficiency of BSA in Alg-g-PVAc/CS microcapsules are higher,and the release rate of BSA from Alg-g-PVAc/CS microcapsules is slower.The results demonstrate that the introduction of hydrophobic PVAc on alginate can effectively help retard the release of BSA,and the higher degree of substitution is,the slower the release rate is.In addition,the complex membrane can also be adjusted to delay the release of BSA.As a whole,amphiphilic sodium alginate-vinyl acetate/CS microparticles could be developed for macromolecular drug delivery.展开更多
Bus dispatching has been studied,and also the bus dispatching model is set up.Then,Genetic Algorithm is adaptively improved in order to avoid premature problem and the slow convergence,and then the keeping optimal str...Bus dispatching has been studied,and also the bus dispatching model is set up.Then,Genetic Algorithm is adaptively improved in order to avoid premature problem and the slow convergence,and then the keeping optimal strategy is used to the Genetic Algorithm,so formed the Improved Adaptive Genetic Algorithm,namely IAGA. Finally,the IAGA is used to optimizing the bus dispatching model,and the results of the simulation indicate IAGA has the higher efficiency than simple GA and is one effective way to optimizing the bus dispatching.展开更多
在VoIP(Voice over Internet Protocol)通信中H.323协议消息携带的地址信息在穿越NAT(Network Address Translation)时,传统的ALG(Apply Layer Gateway)方案采用的全部解码方法,性能较低。为了解决此问题,本文分析ALG技术,采用按需解码...在VoIP(Voice over Internet Protocol)通信中H.323协议消息携带的地址信息在穿越NAT(Network Address Translation)时,传统的ALG(Apply Layer Gateway)方案采用的全部解码方法,性能较低。为了解决此问题,本文分析ALG技术,采用按需解码的方法,只解码消息的地址信息部分,不需全部重新编码,并做对比实验。结果表明,按需解码所需时间约是全部解码方案所需时间的1/75~1/80,优化了ALG的处理性能。展开更多
文摘甘露糖基转移酶Alg11是N糖基化途径中的关键酶,催化第4和第5个甘露糖(Man)残基以α-1,2连键的形式转移到底物Man3-GlcNAc2-PP-Dol生成Man5-GlcNAc2-PP-Dol,人类ALG11基因致病突变会导致相关的先天性糖基化疾病ALG11-CDG(Congenital Disorders of Glycosylation)。目前,对ALG11-CDG的研究更侧重于其临床症状,而患者Alg11突变蛋白的性质还有待探索。作者以研究ALG11-CDG突变蛋白的重组表达及活性为目的,首先在人胚胎肾细胞HEK293和酿酒酵母中分别表达了Alg11野生型及突变体蛋白,发现其表达量存在显著差异,突变体蛋白不能稳定表达。最终在大肠杆菌中成功稳定表达了野生型及ALG11-CDG相关突变蛋白,利用液质联用定量分析了蛋白质的活性,结果显示,突变蛋白的活性存在不同程度的降低,其降低程度与ALG11-CDG疾病的严重程度存在一定的相关性。上述研究结果证明:1)ALG11-CDG相关突变蛋白的不稳定有可能是造成疾病的原因之一;2)体外定量测试大肠杆菌表达的ALG11-CDG相关突变蛋白的活性可以为相应患者的疾病严重程度提供参考。
基金Supported by the National Natural Science Foundation of China(No.21276033)the Open Foundation of the State Key Laboratory of Bioactive Seaweed Substances(Nos.SKL-BASS1711,SKL-BASS1707)the National Undergraduates Innovation and Entrepreneurship Training Program of China(No.201711258000001)
文摘To overcome the fast or burst release of hydrophilic drugs from hydrophilic alginate-based carriers,hydrophobic molecule(vinyl acetate,VAc)was grafted on alginate(Alg),which was further used to prepare drug carriers.Amphiphilic Alg-g-PVAc hydrogel beads were firstly prepared by emulsification/internal gelation technique for the loading of bovine serum albumin(BSA).Then,chitosan was coated on the surface of beads to form novel amphiphilic Alg-g-PVAc/chitosan(Alg-g-PVAc/CS)microcapsules.The BSA-loading amphiphilic Alg-g-PVAc/chitosan(Alg-g-PVAc/CS)microcapsules display similar morphology and size to the hydrophilic alginate/chitosan(AC)microcapsules.However,the drug loading and loading efficiency of BSA in Alg-g-PVAc/CS microcapsules are higher,and the release rate of BSA from Alg-g-PVAc/CS microcapsules is slower.The results demonstrate that the introduction of hydrophobic PVAc on alginate can effectively help retard the release of BSA,and the higher degree of substitution is,the slower the release rate is.In addition,the complex membrane can also be adjusted to delay the release of BSA.As a whole,amphiphilic sodium alginate-vinyl acetate/CS microparticles could be developed for macromolecular drug delivery.
基金supported by the Research Project of "SUST Spring Bud"(2008AZZ069)Graduate Education Innovative Project of Shandong Province (SDYC08011)the "Taishan Scholarship" Construction Engineering
文摘Bus dispatching has been studied,and also the bus dispatching model is set up.Then,Genetic Algorithm is adaptively improved in order to avoid premature problem and the slow convergence,and then the keeping optimal strategy is used to the Genetic Algorithm,so formed the Improved Adaptive Genetic Algorithm,namely IAGA. Finally,the IAGA is used to optimizing the bus dispatching model,and the results of the simulation indicate IAGA has the higher efficiency than simple GA and is one effective way to optimizing the bus dispatching.
文摘在VoIP(Voice over Internet Protocol)通信中H.323协议消息携带的地址信息在穿越NAT(Network Address Translation)时,传统的ALG(Apply Layer Gateway)方案采用的全部解码方法,性能较低。为了解决此问题,本文分析ALG技术,采用按需解码的方法,只解码消息的地址信息部分,不需全部重新编码,并做对比实验。结果表明,按需解码所需时间约是全部解码方案所需时间的1/75~1/80,优化了ALG的处理性能。