|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Metabolic engineering and flux analysis of Corynebacterium glutamicum for L-serine production显示文摘L-Serine plays a critical role as a building block for cell growth, and thus it is difficult to achieve the direct fermentation of L-serine from glucose. In this study, Corynebacterium glutamicum ATCC 13032 was engineered de novo by blocking and attenuating the conversion of L-serine to pyruvate and glycine, releasing the feedback inhibition by L-serine to 3-phosphoglycerate dehydrogenase (PGDH), in combination with the co-expression of 3-phosphoglycerate kinase (PGK) and feedback-resistant PGDH (PGDHr). The resulting strain, SER-8, exhibited a lower specific growth rate and significant differences in L-serine levels from Phase I to Phase V as determined for fed-batch fermentation. The intracellular L-serine pool reached (14.22±1.41) μmol gCDM 1, which was higher than glycine pool, contrary to fermentation with the wild-type strain. Furthermore, metabolic flux analysis demonstrated that the over-expression of PGK directed the flux of the pentose phosphate pathway (PPP) towards the glycolysis pathway (EMP), and the expression of PGDHr improved the L-serine biosynthesis pathway. In addition, the flux from L-serine to glycine dropped by 24%, indicating that the deletion of the activator GlyR resulted in down-regulation of serine hydroxymethyltransferase (SHMT) expression. Taken together, our findings imply that L-serine pool management is fundamental for sustaining the viability of C. glutamicum, and improvement of C1 units generation by introducing the glycine cleavage system (GCV) to degrade the excessive glycine is a promising target for L-serine production in C. glutamicum. | LAI ShuJuan ZHANG Yun LIU ShuWen LIANG Yong SHANG XiuLing CHAI Xin WEN TingYi | 2012 | Science China(Life Sciences)2012，55，4： | 15 |
| 2 | Impact of Temperature on Absorption Coefficient of Pure Seawater in the Blue Wavelengths Inferred from Satellite and In Situ Measurements显示文摘There has been a long history of interest on how(if)the absorption coefficient of“pure”fresh water(a_(fw)(λ))and“pure”seawater(a_(sw)(λ))changes with temperature(T),yet the impact of T reported in the literature differs significantly in the blue domain.Unlike the previous studies based on laboratory measurements,we took an approach based on~18 years(2002–2020)of MODIS ocean color and temperature measurements in the oligotrophic oceans,along with field measured chlorophyll concentration and phytoplankton absorption coefficient,to examine the relationship between T and the total absorption coefficient(a(λ))at 412 and 443 nm.We found that the values of a(412)and a(443)in the summer are nearly flat(slightly decreasing)for the observed T range of~19–27℃.Since there are no detectable changes of chlorophyll during this period,the results suggest that T has a negligible impact on a_(sw)(412) and a_(sw)(443)in this T range.As a complement,the impact of salinity on a_(fw)(λ) was also evaluated using three independent determinations of a_(sw)(λ) and a_(fw)(λ),where good agreements were found from these observations. | Guomei Wei Zhongping Lee Xiuling Wu Xiaolong Yu Shaoling Shang Ricardo Letelier | 2021 | Journal of Remote Sensing2021，，1： | 1 |
| 3 | Optimization of central venous pressure during the perioperative period is associated with improved prognosis of high-risk operation patients显示文摘Background:While central venous pressure(CVP)measurement is used to guide fluid management for high-risk surgical patients during the perioperative period,its relationship to patient prognosis is unknown.Methods:This single-center,retrospective observational study enrolled patients undergoing high-risk surgery from February 1,2014 to November 31,2020,who were admitted to the surgical intensive care unit(ICU)directly after surgery.Patients were divided into the following three groups according to the first CVP measurement(CVP1)after admission to the ICU:low,CVP1<8 mmHg;moderate,8 mmHg≤CVP1≤12 mmHg;and high,CVP1>12 mmHg.Perioperative fluid balance,28-day mortality,length of stay in the ICU,and hospitalization and surgical complications were compared across groups.Results:Of the 775 high-risk surgical patients enrolled in the study,228 were included in the analysis.Median(interquartile range)positive fluid balance during surgery was lowest in the low CVP1 group and highest in the high CVP1 group(low CVP1:770[410,1205]mL;moderate CVP1:1070[685,1500]mL;high CVP1:1570[1008,2000]mL;all P<0.001).The volume of positive fluid balance during the perioperative period was correlated with CVP1(r=0.336,P<0.001).The partial arterial pressure of oxygen(PaO 2)/fraction of inspired oxygen(FiO 2)ratio was significantly lower in the high CVP1 group than in the low and moderate CVP1 groups(low CVP1:400.0[299.5,443.3]mmHg;moderate CVP1:362.5[330.0,434.9]mmHg;high CVP1:335.3[254.0,363.5]mmHg;all P<0.001).The incidence of postoperative acute kidney injury(AKI)was lowest in the moderate CVP1 group(low CVP1:9.2%;moderate CVP1:2.7%;high CVP1:16.0%;P=0.007).The proportion of patients receiving renal replacement therapy was highest in the high CVP1 group(low CVP1:1.5%;moderate CVP1:0.9%;high CVP1:10.0%;P=0.014).Logistic regression analysis showed that intraoperative hypotension and CVP1>12 mmHg were risk factors for AKI within 72 h after surgery(adjusted odds ratio[aOR]=3.875,95%confidence interval[CI]:1.378–10.900,P=0.010 and aOR=1.147,95%CI:1.006–1.309,P=0.041).Conclusions:CVP that is either too high or too low increases the incidence of postoperative AKI.Sequential fluid therapy based on CVP after patients are transferred to the ICU post-surgery does not reduce the risk of organ dysfunction caused by an excessive amount of intraoperative fluid.However,CVP can be used as a safety limit indicator for perioperative fluid management in high-risk surgical patients. | Jiafang Wu Jun Li Han Chen Xiuling Shang Rongguo Yu | 2023 | Journal of Intensive Medicine2023，3，2： | 0 |
| 4 | Expert consensus on the diagnosis and treatment of severe and critical coronavirus disease 2019(COVID-19)显示文摘Introduction Coronavirus disease 2019(COVID-19),a disease caused by severe acute respiratory syndrome-coronavirus-2(SARS-CoV-2),is highly contagious[1]and has developed into a global pan-demic.Up to July 1,2022,COVID-19 has affected>200 coun-tries and regions across the globe and caused 545,226,550 con-firmed cases and 6334,728 deaths,[2]seriously compromising human life,public properties. | You Shang Jianfeng Wu Jinglun Liu Yun Long Jianfeng Xie Dong Zhang Bo Hu Yuan Zong Xuelian Liao Xiuling Shang Renyu Ding Kai Kang Jiao Liu Aijun Pan Yonghao Xu Changsong Wang Qianghong Xu Xijing Zhang Jicheng Zhang Ling Liu Jiancheng Zhang Yi Yang Kaijiang Yu Xiangdong Guan Dechang Chen Chinese Society of Critical Care Medicine,Chinese Medical Association | 2022 | Journal of Intensive Medicine2022，2，4： | 0 |
| 5 | Optimization of the Ethanol Extraction Method of Monoester Alkaloids from Radix Aconiti Preparata Based on HPLC-MS and Orthogonal Test显示文摘[Objectives] This study was conducted to optimize the ethanol extraction technology of monoester alkaloids from Radix Aconiti Preparata. [Methods]On the basis of defined extraction times,ethanol concentration,ethanol times and extraction time were investigated by HPLC-MS combined with orthogonal test to optimize extraction process using the content of monoester alkaloids( the sum of benzoyl neoaconitine,benzoyl hypoaconitine and benzoyl aconitine) as an index.[Results]The optimum ethanol extraction technology was as follows: 75% ethanol,ethanol amount 25 times of the medicinal material,and each extraction for 1. 5 h.[Conclusions] The optimal extraction technology is simple,feasible,stable and reliable. It can provide reference for the industrial production and quality control of monoester alkaloids from Radix Aconiti Preparata. | Changkai ZHOU Rui ZHANG Xiuling SHANG Lihua ZHOU Zukang ZHANG Jing GAO Hongxia YU Hongyan JI Xiaomin XING Qie GUO Donghua LIU Fangang MENG Jingchun YAO Na ZHANG Yongjun LIU Fanbo JING | 2020 | Agricultural Biotechnology2020，9，3： | 0 |
| 6 | Expert consensus on the diagnosis and treatment of severe and critical coronavirus disease 2019显示文摘This consensus focuses on severe and critical coronavi-rus disease 2019(COVID-19)mainly based on the consideration that mortality of severe and critical cases is higher than mild and mo derate cases of COVID-19.Severe patients usually developed dyspnea and/or hypoxemia in a short period of time,and in some cases progressively developed respiratory failure,septic shock,coagulation disorders,and multi-organ dysfunction. | You Shang Jianfeng Wu Jinglun Liu Yun Long Jianfeng Xie Dong Zhang Bo Hu Yuan Zong Xuelian Liao Xiuling Shang Renyu Ding Kai Kang Jiao Liu Ajun Pan Yonghao Xu Changsong Wang Qianghong Xu Xjing Zhang Jicheng Zhang Ling Liu Jiancheng Zhang Yi Yang Kajiang Yu Xiangdong Guan Dechang Chen Chinese Society of Critical Care Medicine Chinese Medical Association | 2022 | Chinese Medical Journal2022，135，16： | 0 |
| 7 | Risk factors for disease severity in COVID-19 patients: A single-center retrospective study显示文摘Background:The outbreak of coronavirus disease 2019(COVID-19)has posed a huge threat to human health.However,little is known regarding the risk factors associated with COVID-19 severity.We aimed to explore early-stage disease risk factors associated with eventual disease severity.Methods:This study enrolled 486 hospitalized,non-intensive care unit(ICU)-admitted adult patients with COVID-19(age≥18 years)treated at Wuhan Jinyintan Hospital,who were divided into three groups according to disease severity.The demographic,clinical,and laboratory data at admission and clinical outcomes were compared among severity groups,and the risk factors for disease severity were identified by multiple regression analysis.Results:Of 486 patients with COVID-19,405(83.33%)were discharged,33(6.71%)died outside of the ICU,and 48(7.20%)were still being treated in the ICU by the time the study period ended.Significant differences in age,lymphocyte counts,and the levels of procalcitonin,aspartate aminotransferase,and D-dimer(P<0.001 for all)among the three groups.Further analysis showed that older age,decreased lymphocyte counts,and increased procalcitonin,aspartate aminotransferase,and D-dimer levels were significantly associated with disease progression.Conclusion:Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)may impair the immune system,the blood coagulation system,and hepatic and cardiac function.Some clinical characteristics and laboratory findings can help identify patients with a high risk of disease severity,which can be significant for appropriate resource allocation during the COVID-19 pandemic. | Jingqing Xu Yanping Cai Min Li Qing Li Yingrui Zhang Ying Jiang Wanli Yan Xuemei Chen Hongxuan Zhang Zhaonan Zeng Fayang Lian Xiuling Shang Rongguo Yu | 2021 | Journal of Intensive Medicine2021，1，2： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员