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441.
Alan K. Hunter Xing Wang Eric J. Suda John T. Herberg Robert E. Shell Kristin E. Thomas Robert L. Dufield Mark E. Gustafson Ned M. Mozier Sa. V. Ho 《Biotechnology progress》2009,25(2):446-453
We have shown how product associating E. coli host cell proteins (HCPs) OppA and DppA can be substantially separated from apolipoprotein A‐IMilano (apo A‐IM) using Butyl Sepharose hydrophobic interaction chromatography (HIC). This work illustrates the complex problems that frequently arise during development and scale‐up of biopharmaceutical manufacturing processes. Product association of the HCPs is confirmed using co‐immunoprecipitation and Western blotting techniques. Two‐dimensional gel electrophoresis and mass spectrometry techniques are used to confirm the identity of OppA and DppA. In this example, clearance of these difficult to separate HCPs decreased significantly when the process was scaled to a 1.4 m diameter column. Laboratory‐scale experimentation and trouble shooting identified several key parameters that could be further optimized to improve HCP clearance. The key parameters included resin loading, peak cut point on the ascending side, wash volume, and wash salt concentration. By implementing all of the process improvements that were identified, it was possible to obtain adequate HCP clearance so as to meet the final specification. Although it remains speculative, it is believed that viscosity effects may have contributed to the lower HCP clearance observed early in the manufacturing campaign. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献
442.
443.
The growing trend of employing multiproduct manufacturing facilities along with the randomness inherent in the biopharmaceutical manufacturing environment is creating significant scheduling and planning challenges for the biopharmaceutical industry. This work focuses on capturing the effect of uncertainty in fermentation titers when optimizing the planning of biopharmaceutical manufacturing campaigns. A mixed integer linear programming (MILP) model based on previous work is derived via chance constrained programming (CCP). The methodology is applied to two illustrative examples, and the results are compared with those from the deterministic model and a multiscenario model accompanied by an iterative construction algorithm. The computational results indicate that the proposed methodology offers significant improvements in solution quality over the compared approaches and presents an opportunity for biopharmaceutical manufacturers to make better medium term planning decisions, particularly under uncertain manufacturing conditions. 相似文献
444.
Driss Mountassif Pierre Andreoletti Mustapha Cherkaoui-Malki Norbert Latruffe M’hammed Saïd El Kebbaj 《Current microbiology》2010,61(1):7-12
To put forward BDH from Pseudomonas aeruginosa’s enzymatic properties, we report a two-step purification of BDH and its gene sequencing allowing the investigation of its
structural properties. Purification of BDH was achieved, using ammonium sulfate fractionation and Blue Sepharose CL-6B affinity
chromatography. SDS–PAGE analysis reveals a MM of 29 kDa, whereas the native enzyme showed a MM of 120 kDa suggesting a homotetrameric
structure. BDH encoding gene sequence shows a nucleotide open reading frame sequence of 771 bp encoding a 265 amino acid residues
polypeptide chain. The modeling analysis of the three dimensional structure fits with the importance of amino acids in the
catalysis reaction especially a strictly conserved tetrad. Amino-acid residues in interaction with the coenzyme NAD+ were also identified. 相似文献
445.
M. W. Z. Basalus K. Tandjung K. G. van Houwelingen M. G. Stoel F. H. A. F. de Man J. W. Louwerenburg S. A. M. Saïd G. C. M. Linssen M. A. W. J. Kleijne J. van der Palen J. Huisman P. M. J. Verhorst C. von Birgelen 《Netherlands heart journal》2010,18(7):360-364
Background. New-generation drug-eluting stents (DES) may solve several problems encountered with first-generation DES, but there is a lack of prospective head-to-head comparisons between new-generation DES. In addition, the outcome of regulatory trials may not perfectly reflect the outcome in ‘real world’ patients. Objectives. To compare the efficacy and safety of two new-generation DES in a ‘real world’ patient population. Methods. A prospective, randomised, single-blinded clinical trial to evaluate clinical outcome after Endeavor Resolute vs. Xience V stent implantation. The primary endpoint is target vessel failure at one-year follow-up. In addition, the study comprises a two-year and an open-label five-year follow-up. (Neth Heart J 2010;18:360-4.) 相似文献
446.
Sa Kan Yoo Qing Deng Peter J. Cavnar Yi I. Wu Klaus M. Hahn Anna Huttenlocher 《Developmental cell》2010,18(2):226-236
Highlights? Neutrophil motility in live zebrafish requires PI(3)K activity at the leading edge ? Localized photo-activation of Rac can to direct migration in vivo ? Rac activation rescues protrusion but not polarization in PI(3)K-inhibited cells ? Separable two-tier regulation of F-actin dynamics and protrusion by PI(3)K 相似文献
447.
448.
Carbon Monoxide Alleviates Wheat Seed Germination Inhibition and Counteracts Lipid Peroxidation Mediated by Salinity 总被引:2,自引:0,他引:2
Sheng Xu Zhi-Sheng Sa Ze-Yu Cao Wei Xuan Ben-Kai Huang Teng-Fang Ling Qiong-Ying Hu Wen-Biao Shen 《植物学报(英文版)》2006,48(10):1168-1176
Recently In animals, endogenous carbon monoxide (CO), like nitric oxlde, was implicated as another Important physiological messenger or bioactive molecule. However, little information is known about the physlologlcal roles of CO in the whole plant. In the present study, we report that different concentrations of the 130 donor hematin (0.1, 1.0 and 10.0 μmol/L) alleviated wheat (Tilticum aestivum L. Yangmai 158) seed germination Inhlbltlon caused by 250 mmol/L NaCI stress In a dose-dependent manner. These responses were also proved by the addltion of different gaseous CO aqueous solutions from 0.1% to 100.0% of saturation. Among these treatments, the effect of 1.0 μmol/L hematin and 1.0% saturation of CO aqueous solution were the most obvlous. Furthermore, compared with non-hematin treatment, the degradation of storage reserves In wheat seeds was also accelerated. Time-course analyses showed that application of hematln dose-dependently Increased the activities of superoxide dismutase, catalase, ascorbate peroxidase, and guaiacol peroxidase activities, thus decreasing the lipid peroxidation In germinating wheat seed subjected to salt stress. Meanwhile, the responses of hematin were specific for CO because the addition of the CO scavenger hemoglobln (0.2 g/L) blocked the various actions of 1.0 μmol/L hematin. Taken together, the results of the present study demonstrate that CO, at a low concentration, is able to attenuate the seed germlnation Inhibition produced by salinity stress and counteract the lipid peroxidation in germinating wheat seeds. 相似文献
449.
The serine-rich (SR) protein family is involved in the pre-mRNA splicing process and the DNA sequences of the corresponding genes are highly conserved in the metazoan organisms. The mammalian SR proteins consist of one or two characteristic RNA binding domains (RBD), containing the signature sequences RDAEDA and SWQDLKD and a RS (arginine/serine-rich) domain. We used the amino acid and nucleotide sequences deposited in GenBank and Swiss-Prot databases to perform a phylogenetic analysis using bioinformatics tools. The results of the phylogenetic trees suggest that this family has evolved by several gene duplication events as a result of a positive selection mechanism. 相似文献
450.
Gallet M Mentaverri R Sévenet N Brazier M Kamel S 《Apoptosis : an international journal on programmed cell death》2006,11(11):1909-1921
We compared the effect of conditioned medium (CM) from several human breast carcinoma cell lines on osteoclast bone resorbing
activity and osteoclast apoptosis. Our findings indicate that ability of cancer cell line to increase the in vitro bone resorbing activity is linked to their potential to inhibit osteoclast apoptosis. Cancer cells producing the higher level
of M-CSF have the higher osteolytic activity, suggesting that M-CSF originating from cancer cells may contribute, at least
in part, to the osteoclast activity at the metastatic site by enhancing their survival. Given that M-CSF plays an important
role in the anti-apoptotic effect, we speculated that blocking M-CSF pathway would prevent the CM effects. Small interfering
RNA (siRNA) targeting M-CSF and imatinib, a protein tyrosine kinase inhibitor targeting M-CSF receptor, almost completely
reversed the CM effect on both osteoclast apoptosis and bone resorption. Blockade of M-CSF pathway could be thus of clinical
value in the treatment of breast cancer related bone destruction. 相似文献