1.Reducing the door-to-needle time for patients with acute ischemic stroke based on the quality improvement program of PDCA cycle
Shan QIN ; Zhong ZHANG ; Xueyi WANG ; Xingyi CAO ; Si TAN ; Qing ZOU ; Zhenqin LIAO ; Linwei CHEN
International Journal of Cerebrovascular Diseases 2017;25(4):331-337
ObjectiveTo investigate the role of reducing the door-to-needle time for patients with acute ischemic stroke based on the quality improvement program of PDCA cycle.MethodsConsecutive patients with acute ischemic stroke admitted to hospital were registered prospectively from January 1, 2016 to September 30, 2016.Questionnaires and time tracking method were used to investigate the door-to-needle (DNT) and its influencing factors.PDCA cycle method was used to improve the stroke channel workflow and the changing trend of DNT was analyzed.ResultsA total of 71 patients with acute ischemic stroke were enrolled.After 3 PDCA cycles, DNT (median, interquartile range) from 100.0 min (65.5-127.0 min) reduced to58.0 min (45.5-80.0 min) (Z=11.689, P<0.001), the proportion of the patients with DNT ≤60 min increased from 19.05% to 60.00% (χ2=7.893, P=0.019).Conclusions The quality improvement program of PDCA cycle may effectively reduce the time of DNT in patients with acute ischemic stroke.
2.Expression of H5N1 avian influenza virus haemagglutinin protein in pichia pastoris by high-density cell fermentation.
Kunyu YANG ; Fangping HE ; Shaowei LI ; Jiahong ZHANG ; Qingshan LIN ; Zhenqin CHEN ; Zhongyi LI ; Jun ZHANG ; Ningshao XIA
Chinese Journal of Biotechnology 2009;25(5):773-778
We produced high pathogenic avian influenza H5N1 haemagglutinin protein HA1 in recombinant Pichia pastoris in a 10 L fermentor, to establish a high-density cell fermentation method. We studied the effects of different factors such as culture temperature, induced temperature, methanol feeding methods, trace elements on the growth of Pichia pastoris, the yield and the biologic activity of recombinant HA1 protein. The culture temperature in pre-induced and induced stage were optimized at 25 degrees C to adapt cell growth and recombinant protein expression, and induced temperature at 25 degrees C also resulted in higher biologic activity of rHA1 than at 30 degrees C. The binding activity of rHA1 against a wide-spectrum neutralizing antibody was susceptible to the presence of any trace elements, although trace elements would essentially benefit for the cell fermentation. As a conclusion, the expression level of rHA1 produced with optimized fermentation process reached 120 mg/L, which was 10.5 times higher than the one produced in regular shaking flask. The resultant high-density cell fermentation can likely produce rHA1 of H5N1 in large scale.
Fermentation
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Hemagglutinins, Viral
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biosynthesis
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genetics
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Influenza A Virus, H5N1 Subtype
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genetics
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metabolism
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Pichia
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genetics
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metabolism
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Recombinant Proteins
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biosynthesis