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971.
972.
Xiao-Hai Feng Fei Chen Hong Xu Bo Wu Jun Yao Han-Jie Ying Ping-Kai Ouyang 《Bioprocess and biosystems engineering》2010,33(9):1077-1085
Propionic acid was produced in a multi-point fibrous-bed (MFB) bioreactor by Propionibacterium freudenreichii CCTCC M207015. The MFB bioreactor, comprising spiral cotton fiber packed in a modified 7.5-l bioreactor, was effective for
cell-immobilized propionic acid production compared with conventional free cell fermentation. Batch fermentations at various
glucose concentrations were investigated in the MFB bioreactor. Based on analysis of the time course of production, a fed-batch
strategy was applied for propionic acid production. The maximum propionic acid concentration was 67.05 g l−1 after 496 h of fermentation, and the proportion of propionic acid to total organic acids was approximately 78.28% (w/w).
The MFB bioreactor exhibited excellent production stability during batch fermentation and the propionic acid productivity
remained high after 78 days of fermentation. 相似文献
973.
Yun‐Jun Liu Cheng‐Hui Zeng Jun‐Hua Yao Fu‐Hai Wu Li‐Xin He Hong‐Liang Huang 《化学与生物多样性》2010,7(7):1770-1783
Many ruthenium(II) complexes show high antitumor activities, and the in vitro antitumor activities are usually related to DNA binding. We designed and synthesized two RuII polypyridyl complexes, [Ru(dmp)2(fpp)]2+ (dmp=2,9‐dimethyl‐1,10‐phenanthroline; fpp=2‐[3,4‐(difluoromethylenedioxy)phenyl]imidazo[4,5‐f] [1,10]phenanthroline and [Ru(phen)2(fpp)]2+ (phen=1,10‐phenanthroline). The DNA‐binding properties of these complexes have been investigated by spectroscopic titration, DNA melting experiments, viscosity measurements, and photoactivated cleavage. The mechanism studies of photocleavage revealed that singlet oxygen (1O2) and superoxide anion radical (O$\rm{{_{2}^{{^\cdot} -}}}$ ) may play an important role in the photocleavage. The cytotoxicity of complexes 1 and 2 have been evaluated by MTT (3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐2H‐tetrazolium bromide) method; complex 2 shows slightly higher anticancer potency than 1 does against all the cell lines screened. 相似文献
974.
Xiaoen Xu Meng Qiao Yang Zhang Yinghua Jiang Ping Wei Jun Yao Bo Gu Yaqi Wang Jing Lu Zhigang Wang Zhaoqing Tang Yihong Sun Wenshu Wu Qian Shi 《Proteomics》2010,10(7):1374-1390
The proteins involved in breast cancer initiation and progression are still largely elusive. To gain insights into these processes, we conducted quantitative proteomic analyses with 21T series of breast cell lines, which include a normal, primary tumor and a metastatic tumor that were isolated from a single patient. Stable isotope labeling of amino acid in cell culture followed by LC‐MS/MS analysis was performed and deregulated proteins were identified using statistical analysis. Gene ontology analysis revealed that proteins involved in metabolic processes were the most deregulated in both tumorigenesis and metastasis. Interaction network analysis indicated that ERBB2 signaling played a critical role in tumorigenesis. In addition to known markers such as ERBB2 and E‐cadherin, novel markers, including BRP44L, MTHFD2 and TIMM17A, were found to be overexpressed in 21T breast cancer cells and verified in additional breast cell lines. mRNA expression analysis as well as immunohistochemistry analysis in breast cancer tissues indicated that expression level of TIMM17A was directly correlated with tumor progression, and survival analysis suggested that TIMM17A was a powerful prognosis factor in breast cancer. More interestingly, overexpression and siRNA knockdown experiments indicated an oncogenic activity of TIMM17A in breast cancer. Our study provides a list of potential novel markers for breast cancer tumorigenesis and metastasis using a unique cell model. Further studies on TIMM17A as well as other markers on the list may reveal mechanisms that result in more effective therapeutics for cancer treatment. 相似文献
975.
976.
Zhi-Min Li Jin-Zhi Zhang Li Mei Xiu-Xin Deng Chun-Gen Hu Jia-Ling Yao 《Plant molecular biology》2010,74(1-2):129-142
977.
Angiogenesis is important in tumor development. Vascular endothelial growth factor (VEGF) is involved in this process. In
this report, we constructed a recombinant protein (called FK) by fusing the second immunoglobulin-like (Ig-like) domain of
a human fms-like tyrosine kinase (Flt-1) with the third Ig-like domain of human kinase insert domain-containing receptor (KDR). FK bound
to VEGF165 in a dose-dependent manner with a disocciation constant (Kd) of 2.7 pM. In addition, FK specifically inhibited the proliferation
of human microvascular endothelial cell (HMEC) and human umbilical vein endothelial Cell (HUVEC) stimulated by VEGF165. Subsequent studies also demonstrate that FK efficaciously suppresses growth of a variety of tumors, which could make FK
a potential drug candidate in anti-tumor therapy. 相似文献
978.
Chunbao Zhang Hongkun Zhao Yanzhi Liu Qiyun Li Xiaodong Liu Hua Tan Cuiping Yuan Yingshan Dong 《Biotechnology letters》2010,32(6):861-866
A novel glycogen synthase kinase-3 gene, GmGSK, was isolated from Glycine
max. It is 1,596 bp in length with one ORF of 410 amino acids. Southern blot analysis revealed that it has at least two copies
in the G. max genome. GmGSK, when transiently expressed in Nicotiana tabacum leaves, was localized in both cell membrane and cytoplasm. Northern blot analysis indicated that GmGSK is expressed in all tissues, with highest expression in the root. GmGSK can be induced by various abiotic stresses. When transformed with GmGSK, Saccharomyces cerevisiae exhibited enhanced resistance to salt and drought stress. 相似文献
979.
S. Amer Riazuddin Amber Shahzadi Zubair M. Ahmed Radha Ayyagari Virgilio G. Ponferrada Christelle Michiels Marie-Elise Lancelot Idrees A. Nasir Shaheen N. Khan Xiaodong Jiao Sheikh Riazuddin Paul A. Sieving J. Fielding Hejtmancik 《American journal of human genetics》2010,87(4):523-531
Congenital stationary night blindness (CSNB) is a nonprogressive retinal disorder that can be associated with impaired night vision. The last decade has witnessed huge progress in ophthalmic genetics, including the identification of three genes implicated in the pathogenicity of autosomal-recessive CSNB. However, not all patients studied could be associated with mutations in these genes and thus other genes certainly underlie this disorder. Here, we report a large multigeneration family with five affected individuals manifesting symptoms of night blindness. A genome-wide scan localized the disease interval to chromosome 15q, and recombination events in affected individuals refined the critical interval to a 10.41 cM (6.53 Mb) region that harbors SLC24A1, a member of the solute carrier protein superfamily. Sequencing of all the coding exons identified a 2 bp deletion in exon 2: c.1613_1614del, which is predicted to result in a frame shift that leads to premature termination of SLC24A1 (p.F538CfsX23) and segregates with the disorder under an autosomal-recessive model. Expression analysis using mouse ocular tissues shows that Slc24a1 is expressed in the retina around postnatal day 7. In situ and immunohistological studies localized both SLC24A1 and Slc24a1 to the inner segment, outer and inner nuclear layers, and ganglion cells of the retina, respectively. Our data expand the genetic basis of CSNB and highlight the indispensible function of SLC24A1 in retinal function and/or maintenance in humans. 相似文献
980.
High-throughput single cell analysis is required for understanding and predicting the complex stochastic responses of individual cells in changing environments. We have designed a microfluidic device consisting of parallel, independent channels with cell-docking structures for the formation of an array of individual cells. The microfluidic cell array was used to quantify single cell responses and the distribution of response patterns of calcium channels among a population of individual cells. In this device, 15 cell-docking units in each channel were fabricated with each unit containing 5 sandbag structures, such that an array of individual cells was formed in 8 independent channels. Single cell responses to different treatments in different channels were monitored in parallel to study the effects of the specific activator and inhibitor of the Ca2+ release-activated Ca2+ (CRAC) channels. Multichannel detection was performed to obtain the response patterns of the population of cells within this single cell array. The results demonstrate that it is possible to acquire single cell features in multichannels simultaneously with passive structural control, which provides an opportunity for high-throughput single cell response analysis in a microfluidic chip. 相似文献