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91.
92.
Helicobacter pylori Activates IL‐6‐STAT3 Signaling in Human Gastric Cancer Cells: Potential Roles for Reactive Oxygen Species 下载免费PDF全文
93.
Genome‐scale RNA interference screen identifies antizyme 1 (OAZ1) as a target for improvement of recombinant protein production in mammalian cells 下载免费PDF全文
94.
Jung Won Shin Sung Hee Choi Dong Eun Kim Hee Sook Kim Jae-Hwa Lee In Su Lee Eun Yeol Lee 《Bioprocess and biosystems engineering》2011,34(1):113-119
The marine alginate lyase from Streptomyces sp. ALG-5, which specifically degrades poly-G block of alginate, was functionally expressed as a His-tagged form with an
Escherichia coli expression system. The recombinant alginate lyase expressed with pColdI at 15 °C exhibited the highest alginate-degrading
activity. The recombinant alginate lyase was efficiently immobilized onto two types of magnetic nanoparticles, superparamagnetic
iron oxide nanoparticle, and hybrid magnetic silica nanoparticle, based on the affinity between His-tag and Ni2+ that displayed on the surfaces of nanoparticles. An alginate oligosaccharide mixture consisting of dimer and trimer was prepared
by the immobilized alginate lyase. The immobilized enzymes were re-used repeatedly more than 10 times after magnetic separation. 相似文献
95.
E. S. Seong J. H. Yoo N. J. Kim J. H. Choi J. G. Lee B. K. Ghimire I. M. Chung C. Y. Yu 《Russian Journal of Plant Physiology》2016,63(1):124-131
The tomato bZIP2-encoding gene was inserted into the Nicotiana benthamiana genome using Agrobacterium-mediated transformation to characterize resistance to oxidative stress and two herbicides, glyphosate and paraquat. We produced transgenic tobacco plants using the LebZIP2 gene, which were then utilized to examine salt stress and herbicide resistance through oxidative mechanisms. Transgenic LebZIP2-overexpressing plants were examined using specific primers for selection marker genes (PCR using genomic DNA) and target genes (RT-PCR). Based on microscopic examination, we observed an increase in leaf thickness and cell number in transgenic plants. The electrolyte leakage of leaves suggested that LebZIP2-overexpressing lines were weak tolerant to NaCl stress and resistant to methyl viologen. During our analysis, transgenic lines were exposed to different herbicides. Transgenic plants showed an increased tolerance based on visual injury, as well as an increased biomass. Based on these results, the LebZIP2 gene may be involved in oxidative stress tolerance and cell development in plants. 相似文献
96.
Yi SS Hwang IK Kim DW Shin JH Nam SM Choi JH Lee CH Won MH Seong JK Yoon YS 《Neurochemical research》2011,36(1):117-128
Because it appears that oxidative stress and inflammation are implicated with disease pathogenesis in the diabetic brain,
many researchers have used streptozotocin (STZ)-induced diabetic animals to study superoxide production and the effects of
superoxide scavengers like Cu,Zn-superoxide dismutase (SOD1). However, many studies have been conducted without considering
temporal changes after STZ injection. Interestingly, though SOD activities were not significantly different among the groups,
SOD1 and 4-hydroxy-2-nonenal (4-HNE) immunoreactivities were significantly enhanced at 3 weeks after an STZ injection (STZ3w)
versus only marginal levels in sham controls, whereas microglial activity was remarkably reduced in injected rats at this
time. However, SOD1 immunoreactivity and microglial activities were only at the sham level at STZ4w. The present study provides
important information concerning cell damage by ROS generated by STZ. Microglial response was found to be inactivated at STZ3w
and neuronal cells (NeuN) showed a non-significant tendency to be reduced in number at STZ4w except in the dentate gyrus.
We speculated that the above oxidative stress-related events should be accomplished at STZ3w in the brains of STZ-induced
diabetes animal models. Therefore, the aim of the present study was to investigate chronological changes in SOD1 immunoreactivity
associated with lipid peroxidation and inflammatory responses in the hippocampi of STZ-induced type I diabetic rats. 相似文献
97.
98.
Aurora B kinase (Aurora-B) functions in chromosome segregation and cleavage of polar spindle microtubules. However, its role in cellular senescence remains elusive. Here, we investigated Aurora-B effects on cellular senescence in human fibroblasts and endothelial cells. Aurora-B levels were reduced during replicative senescence and premature senescence by adriamycin. Aurora-B overexpression in old cells partially reversed senescence phenotypes. In contrast, Aurora-B down-regulation accelerated cellular senescence. p53 knockdown but not p16 knockdown inhibited cellular senescence by Aurora-B reduction. These results suggest that Aurora-B might function in the regulation of cellular senescence of human primary cells via a p53-dependent pathway. 相似文献
99.
Loll B Rückert C Hee CS Saenger W Uchanska-Ziegler B Ziegler A 《Protein science : a publication of the Protein Society》2011,20(2):278-290
The human major histocompatibility complex class I antigen HLA‐B*2705 binds several sequence‐related peptides (pVIPR, RRKWRRWHL; pLPM2, RRRWRRLTV; pGR, RRRWHRWRL). Cross‐reactivity of cytotoxic T cells (CTL) against these HLA‐B*2705:peptide complexes seemed to depend on a particular peptide conformation that is facilitated by the engagement of a crucial residue within the binding groove (Asp116), associated with a noncanonical bulging‐in of the middle portion of the bound peptide. We were interested whether a conformational reorientation of the ligand might contribute to the lack of cross‐reactivity of these CTL with a peptide derived from voltage‐dependent calcium channel α1 subunit (pCAC, SRRWRRWNR), in which the C‐terminal peptide residue pArg9 could engage Asp116. Analyses of the HLA‐B*2705:pCAC complex by X‐ray crystallography at 1.94 Å resolution demonstrated that the peptide had indeed undergone a drastic reorientation, leading it to adopt a canonical binding mode accompanied by the loss of molecular mimicry between pCAC and sequence‐related peptides such as pVIPR, pLMP2, and pGR. This was clearly a consequence of interactions of pArg9 with Asp116 and other F‐pocket residues. Furthermore, we observed an unprecedented reorientation of several additional residues of the HLA‐B*2705 heavy chain near the N‐terminal region of the peptide, including also the presence of double conformations of two glutamate residues, Glu63 and Glu163, on opposing sides of the peptide binding groove. Together with the Arg‐Ser exchange at peptide position 1, there are thus multiple structural reasons that may explain the observed failure of pVIPR‐directed, HLA‐B*2705‐restricted CTL to cross‐react with HLA‐B*2705:pCAC complexes. 相似文献
100.
Kwak SJ Paeng J Kim do H Lee SH Nam BY Kang HY Li JJ Jung DS Han SH Ryu DR Park JT Chang TI Yoo TH Han DS Kang SW 《Apoptosis : an international journal on programmed cell death》2011,16(5):478-490
The kallikrein-kinin system (KKS) serves as the physiologic counterbalance to the renin-angiotensin system. This study was conducted to examine the changes in the expression of KKS components in podocytes under diabetic conditions and to elucidate the functional role of bradykinin (BK) in diabetes-associated podocyte apoptosis. Thirty-two rats were injected with either diluent (n = 16, C) or with streptozotocin intraperitoneally (n = 16, DM), and 8 rats from each group were treated with BK infusion for 6 weeks. Immortalized mouse podocytes were cultured in media containing 5.6 mmol/l glucose (NG), NG + 10(-7) mol/l AII (AII), or 30 mmol/l glucose (HG) with or without 10(-8) mol/l BK. Urinary albumin excretion was significantly higher in DM rats, and this increase was ameliorated by BK. Not only kininogen, kallikrein, and BK B1- and B2-receptor expression but also BK levels were significantly decreased in DM glomeruli and in cultured podocytes exposed to HG. The changes in the expressions of apoptosis-related molecules and the increase in the number of apoptotic cells in DM glomeruli as well as in HG- and AII-stimulated podocytes were significantly abrogated by BK. The suppressed KSS within podocytes under diabetic condition was associated with podocyte apoptosis, suggesting that BK may be beneficial in preventing podocyte loss in diabetic nephropathy. 相似文献