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Effect of a promoter on the methanation activity of a Mo-based sulfur-resistant catalyst

Can LIN, Haiyang WANG, Zhenhua LI, Baowei WANG, Xinbin MA, Shaodong QIN, Qi SUN

《化学科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 88-94 doi: 10.1007/s11705-013-1301-1

摘要： The effect of adding Co, Ni or La on the methanation activity of a Mo-based sulfur-resistant catalyst was investigated. As promoters, Co, Ni and La all improved the methanation activity of a 15% MoO /Al O catalyst but to different extents. Similar improvements were also found when Co, Ni or La was added to a 15% MoO /25%-CeO -Al O catalyst. The promotion effects of Co and Ni were better than that of La. However, the catalytic methanation activity deteriorated the most with time for the Ni-promoted catalyst. The used catalysts were analyzed by nitrogen adsorption measurement, X-ray diffraction and X-ray photoelectron spectroscopy.

关键词： sulfur-resistant     methanation     promoter    

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Cloning of human XAF1 gene promoter and assay of its transcription activity in a variety of cell lines

Qiong CHEN, Qing YU, Yuhu SONG, Peiyuan Li, Ying CHANG, Zhijun WANG, Lifeng LIU, Wei WU, Jusheng LIN

《医学前沿（英文）》 2009年 第3卷 第2期   页码 148-152 doi: 10.1007/s11684-009-0032-7

摘要： To investigate the regulation of tumor suppressor XAF1 gene expression in digestive system cancers, we studied XAF1 gene promoter transcription activity and mRNA level in digestive system cancer cell lines (human hepatoma cell line HepG2, human colon cancer cell line LoVo, and human gastric cancer cell line AGS) and nontumor cell lines (human embryonic liver cell line L02 (L02 cells) and human embryonic kidney 293 cells [HEK293 cells]) as controls. 1395-bp-promoter fragment of XAF1 gene was amplified by polymerase chain reaction (PCR) and cloned into pGL3-basic vector and pEGFP-1 vector to assay its promoter transcription activity. The plasmids were transfected into a variety of cell lines by lipofectamine 2000. The promoter transcription activity was determined by dual-luciferase report assay, and enhanced green fluorescent protein (EGFP)-positive cells were detected by fluorescence microscope. The expression of XAF1 mRNA in HEK293 and L02 were significantly higher than that in any of the three digestive system cancer cell lines. The dual-luciferase reporter assay showed that the promoter transcription activity in digestive system tumor cell lines transfected with pGL3-XAF1p promoter was apparently lower than that of both HEK293 and L02 cells. Expression of green fluorescent protein (GFP) under the control of XAF1 promoter in the three digestive system cancer cell lines was lower than that of both HEK293 and L02 cells. The activities of pGL3-XAF1p in the three digestive system cancer cell lines after treatment with heat stress were significantly lower than those in the unstressed cells. The results suggested that remarkably down-regulated XAF1 mRNA expression in digestive system cancer cell lines may be due to loss of transcription activity of XAF1 promoter.

关键词： gene     X-linked inhibitor of apoptosis protein associated factor-1 (XAF1)     promoter     transcription regulation    

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Construction, characterization and application of a genome-wide promoter library in

Ting Yuan,Yakun Guo,Junkai Dong,Tianyi Li,Tong Zhou,Kaiwen Sun,Mei Zhang,Qingyu Wu,Zhen Xie,Yizhi Cai,Limin Cao,Junbiao Dai

《化学科学与工程前沿（英文）》 2017年 第11卷 第1期   页码 107-116 doi: 10.1007/s11705-017-1621-7

摘要： Promoters are critical elements to control gene expression but could behave differently under various growth conditions. Here we report the construction of a genome-wide promoter library, in which each native promoter in was cloned upstream of a yellow fluorescent protein (YFP) reporter gene. Nine libraries were arbitrarily defined and assembled in bacteria. The resulting pools of promoters could be prepared and transformed into a yeast strain either as centromeric plasmids or integrated into a genomic locus upon enzymatic treatment. Using fluorescence activated cell sorting, we classified the yeast strains based on YFP fluorescence intensity and arbitrarily divided the entire library into 12 bins, representing weak to strong promoters. Several strong promoters were identified from the most active bins and their activities were assayed under different growth conditions. Finally, these promoters were applied to drive the expression of genes in xylose utilization to improve fermentation efficiency. Together, this library could provide a quick solution to identify and utilize desired promoters under user-defined growth conditions.

关键词： synthetic biology     yeast     promoter activity     metabolic engineering     xylose utilization    

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Osteopontin is a promoter for hepatocellular carcinoma metastasis: a summary of 10 years of studies

null

《医学前沿（英文）》 2014年 第8卷 第1期   页码 24-32 doi: 10.1007/s11684-014-0312-8

摘要：

In this review, we summarize the novel findings from our series of studies on the leading metastasis-related gene, osteopontin (OPN). In our previous gene expression profiling study, OPN was identified as one of the leading genes associated with the metastasis of hepatocellular carcinoma (HCC). We focused on OPN to evaluate its prognostic values and important roles in HCC metastasis. A retrospective study of large cohorts of HCC patients demonstrated that plasma OPN level was one of the leading independent prognostic factors for HCC patients, even in the early stage of HCC, and could serve as a surrogate serologic biomarker for monitoring the treatment response and tumor recurrence after HCC resection. Using both in vitro and in vivoinvestigations, we found that OPN has an important role in metastasis and tumor growth of HCC and is an attractive potential therapeutic target for combating HCC metastasis. We also found that OPN+ HCC cells have much more amplifications at chromosomal regions, and promoter polymorphisms are important in the regulation of OPN expression and tumor growth and lung metastasis of HCC.

关键词： osteopontin (OPN)     hepatocellular carcinoma     metastasis     prognosis     therapeutic target     biomarker     genetic polymorphism    

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Distinct gene expression pattern of mutations coordinated by target repression and promoter hypermethylation

《医学前沿（英文）》 2022年 第16卷 第4期   页码 627-636 doi: 10.1007/s11684-020-0815-4

摘要： Runt-related transcription factor 1 (RUNX1) is an essential regulator of normal hematopoiesis. Its dysfunction, caused by either fusions or mutations, is frequently reported in acute myeloid leukemia (AML). However, RUNX1 mutations have been largely under-explored compared with RUNX1 fusions mainly due to their elusive genetic characteristics. Here, based on 1741 patients with AML, we report a unique expression pattern associated with RUNX1 mutations in AML. This expression pattern was coordinated by target repression and promoter hypermethylation. We first reanalyzed a joint AML cohort that consisted of three public cohorts and found that RUNX1 mutations were mainly distributed in the Runt domain and almost mutually exclusive with NPM1 mutations. Then, based on RNA-seq data from The Cancer Genome Atlas AML cohort, we developed a 300-gene signature that significantly distinguished the patients with RUNX1 mutations from those with other AML subtypes. Furthermore, we explored the mechanisms underlying this signature from the transcriptional and epigenetic levels. Using chromatin immunoprecipitation sequencing data, we found that RUNX1 target genes tended to be repressed in patients with RUNX1 mutations. Through the integration of DNA methylation array data, we illustrated that hypermethylation on the promoter regions of RUNX1-regulated genes also contributed to dysregulation in RUNX1-mutated AML. This study revealed the distinct gene expression pattern of RUNX1 mutations and the underlying mechanisms in AML development.

关键词： RUNX1     gene mutation     acute myeloid leukemia     transcriptional repression     DNA methylation    

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Effects of MgO promoter on properties of Ni/Al2O3 catalysts for partial oxidation of methane to syngas

QIU Yejun, CHEN Jixiang, ZHANG Jiyan

《化学科学与工程前沿（英文）》 2007年 第1卷 第2期   页码 167-171 doi: 10.1007/s11705-007-0031-7

摘要： The effects of MgO promoter on the physico-chemical properties and catalytic performance of Ni/AlO catalysts for the partial oxidation of methane to syngas were studied by means of BET, XRD, H-TPR, TEM and performance evaluation. It was found that the MgO promoter benefited from the uniformity of nickel species in the catalysts, inhibited the formation of NiAlO spinel and improved the interaction between nickel species and support. These results were related to the formation of NiO MgO solid solution and MgAlO spinel. Moreover, for the catalysts with a proper amount of MgO promoter, the nickel dispersiveness was enhanced, therefore making their catalytic performance in methane partial oxidation improved. However, the excessive MgO promoter exerted a negative effect on the catalytic performance. Meanwhile, the basicity of MgO promoted the reversed water gas shift reaction, which led to an increase in CO selectivity and a decrease in H2 selectivity. The suitable content of MgO promoter in Ni/AlO catalyst was ?7 wt-%.

关键词： excessive     selectivity     decrease     dispersiveness     physico-chemical    

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IDEEA activity monitor: validity of activity recognition for lying, reclining, sitting and standing

null

《医学前沿（英文）》 2013年 第7卷 第1期   页码 126-131 doi: 10.1007/s11684-012-0236-0

摘要：

Recent evidence demonstrates the independent negative effects of sedentary behavior on health, but there are few objective measures of sedentary behavior. Most instruments measure physical activity and are not validated as measures of sedentary behavior. The purpose of this study was to evaluate the validity of the IDEEA system’s measures of sedentary and low-intensity physical activities: lying, reclining, sitting and standing. Thirty subjects, 14 men and 16 women, aged 23 to 77 years, body mass index (BMI) between 18 to 34 kg/m2, participated in the study. IDEEA measures were compared to direct observation for 27 activities: 10 lying in bed, 3 lying on a sofa, 1 reclining in a lawn chair, 10 sitting and 3 standing. Two measures are reported, the percentage of activities accurately identified and the percentage of monitored time that was accurately labeled by the IDEEA system for all subjects. A total of 91.6% of all observed activities were accurately identified and 92.4% of the total monitored time was accurately labeled. The IDEEA system did not accurately differentiate between lying and reclining so the two activities were combined for calculating accuracy. Using this approach the IDEEA system accurately identified 96% of sitting activities for a total of 97% of the monitored sitting time, 99% and 99% for standing, 87% and 88% for lying in bed, 87% and 88% for lying on the sofa, and 83% and 83% for reclining on a lawn chair. We conclude that the IDEEA system accurately recognizes sitting and standing positions, but it is less accurate in identifying lying and reclining positions. We recommend combining the lying and reclining activities to improve accuracy. The IDEEA system enables researchers to monitor lying, reclining, sitting and standing with a reasonable level of accuracy and has the potential to advance the science of sedentary behaviors and low-intensity physical activities.

关键词： IDEEA     activity monitor     sedentary behavior    

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Production of pectic extracts from sugar beet pulp with antiproliferative activity on a breast cancer

Jacqueline CONCHA, Caroline WEINSTEIN, María Elvira Zú?IGA

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 482-489 doi: 10.1007/s11705-013-1342-5

摘要： In the last years, sugar beet pectins have been the subject of several investigations involving extraction methodologies, chemical composition and functional properties. The structure of pectins, which depends on the extraction method, is decisive in their capacity to induce apoptosis on several cancer cell lines like colon, prostate and breast. In this work, sugar beet pectin extraction was performed in the following steps: lipid extraction with hexane, removal of soluble complex carbohydrates and proteins, and enzymatic treatment with amyloglucosidase, protease, and pectinase. The enzymatic treatment was carried out with Rohapect DA6L under the following conditions: 50°C, pH 4.0, 2% enzyme/substrate (E/S) ratio, 15 h, and a solid to liquid ratio of 1 ∶ 10. The pectic extract showed a degree of polymerization (DP) profile of 55.8% with DP≥7; 4.9% with DP6; 5.8% between DP2 and DP6 ; 4.7% with DP2; and 28.8% with DP1. The pectic extract was examined for its antiproliferative activity on the MCF-7 breast cancer cell line. At a concentration range of 12.5–25 mg/mL the pectic extract killed 80.6% of the cells, exhibiting a higher antiproliferative activity than 4-hydroxytamoxifen (4-OHT), a classical anticancer drug, which killed 56.5% of the cells.

关键词： pectic extracts     antiproliferative activity     breast cancer     enzymatic treatment    

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Effect of 2-butenal manufacture wastewater to methanogenic activity and microbial community

Guangqing Song, Hongbo Xi, Xiumei Sun, Yudong Song, Yuexi Zhou

《环境科学与工程前沿（英文）》 2018年 第12卷 第5期 doi: 10.1007/s11783-018-1056-5

摘要：

The inhibition ratio sharply increased with the increasing COD.

The absorbance of UV-vis at 420 nm showed a linear correlation with the SMA.

The molecular structure of EPS has changed when COD was 9585 mg/L.

Illumina Miseq sequencing was employed to reveal the microbial composition.

关键词： 2-butenal manufacture wastewater     Methanogenic activity     Specific methanogenic activity (SMA)     Extracellular polymeric substance (EPS)     Microbial community    

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Low intensity ultrasound stimulates biological activity of aerobic activated sludge

LIU Hong, YAN Yixin, WANG Wenyan, YU Yongyong

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 67-72 doi: 10.1007/s11783-007-0013-5

摘要： This work aims to explore a procedure to improve biological wastewater treatment efficiency using low intensity ultrasound. The aerobic activated sludge from a municipal wastewater treatment plant was used as the experimental material. Oxygen uptake rate (OUR) of the activated sludge (AS) was determined to indicate the changes of AS activity stimulated by ultrasound at 35 kHz for 0 40 min with ultrasonic intensities of 0 1.2 W/cm. The highest OUR was observed at the ultrasonic intensity of 0.3 W/cm and an irradiation period of 10 min; more than 15% increase was achieved immediately after sonication. More significantly, the AS activity stimulated by ultrasound could last 24 h after sonication, and the AS activity achieved its peak value within 8 h after sonication, or nearly 100% higher than the initial level after sonication. Therefore, to improve the wastewater treatment efficiency of bioreactors, ultrasound with an intensity of 0.3 W/cm could be employed to irradiate a part of the AS in the bioreactor for 10 min every 8 h.

关键词： sonication     irradiation     kHz     treatment efficiency     AS activity    

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A survey of physical activity among urban women in China

Shilin DENG MD, Tongyuan LIU,

《医学前沿（英文）》 2009年 第3卷 第4期   页码 463-469 doi: 10.1007/s11684-009-0081-y

摘要： Few studies have been conducted to assess the level of physical activity (PA) of women in China. The purpose of this study was to describe the prevalence of PA among women in Wuhan and explore sociodemographic and behavioral correlation to PA for the population. A total of 1359 community-dwelling women (42.9713.60 years old) participated in this study. The long-version IPAQ was used to define the level of PA. 45.7% of women were considered physically active, and 27.5% were vigorously active. The proportion of physical inactivity was around 26.8%. The total and 4 domains of PA showed significant age, education level, and occupation variation. PA tended to be lower as the age declined. PA in transportation, housework, leisure time, and the total tended to be the lowest or the second lowest among the women aged 18–35 years old. PA tended to be lower as the level of education increased. Among the 5 indices, PAwas the lowest among women with college education, especially those with postgraduate education. PA tended to be the lowest among the women of office staff and instructor or technician. Generally, the total and 4 domains of PA showed significant age, education level, and occupation variation. Physical inactivity appears to be more common among younger women, or college-educated women, office ladies, and female instructor and technicians.

关键词： physical activity     urban women     China    

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preparation of Ag@AgCl/Bio-veins composites and their photocatalytic activity and recyclability

《化学科学与工程前沿（英文）》 2023年 第17卷 第7期   页码 906-917 doi: 10.1007/s11705-022-2273-9

摘要： The industrial application of nano-photocatalysts in wastewater treatment has been severely restricted for a long time due to their difficult separation, poor reusability, and low efficiency. In this work, a facile strategy was proposed to enhance the photocatalytic activity and recovery performance of Ag@AgCl nanocatalysts. Biological veins (Bio-veins) with a unique 3D porous construction were used as carriers for the in-situ growth of Ag@AgCl nanoparticles. Scanning electron microscopy results showed that the Ag@AgCl nanoparticles were uniformly loaded on the surface and interior of the Bio-veins, and the size of the Ag@AgCl nanoparticles immobilized on the Bio-veins (50–300 nm) was significantly smaller than Ag@AgCl obtained by the co-precipitation method (1–3 μm). The Bio-veins played a vital role in the photocatalysis reaction system. The degradation efficiency of the Ag@AgCl/Bio-veins(CI4) was up to 3.50 times as high as pure Ag@AgCl. Furthermore, the composites also exhibited excellent recyclability and stability under both visible and solar light. This work provided a suitable strategy for nano-photocatalysts for practical application and may also offer new possibilities for the high-value utilization of biomass materials.

关键词： Ag@AgCl     biological veins     photocatalytic activity     recyclability    

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Antithrombin deficiency and decreased protein C activity in a young man with venous thromboembolism:

null

《医学前沿（英文）》 2018年 第12卷 第3期   页码 319-323 doi: 10.1007/s11684-017-0553-4

摘要：

Antithrombin and protein C are two crucial members in the anticoagulant system and play important roles in hemostasis. Mutations in and lead to deficiency or dysfunction of the two proteins, which could result in venous thromboembolism (VTE). Here, we report a Chinese 22-year-old young man who developed recurrent and serious VTE in cerebral veins, visceral veins, and deep veins of the lower extremity. Laboratory tests and direct sequencing of and were conducted for the patient and his family members. Coagulation tests revealed that the patient presented type I antithrombin deficiency combined with decreased protein C activity resulting from a small insertion mutation c.848_849insGATGT in and a short deletion variant c.572_574delAGA in . This combination of the two mutations was absent in 400 healthy subjects each from southern and northern China. Then, we summarized all the mutations of the and gene reported in the Chinese Han population. This study demonstrates that the combination of antithrombin deficiency and decreased protein C activity can result in severe VTE and that the coexistence of different genetic factors may increase the risk of VTE.

关键词： antithrombin deficiency     protein C activity     mutation     variant     venous thromboembolism     anticoagulants    

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Probing the catalytic activity of M-N

Fan Ge, Qingan Qiao, Xin Chen, You Wu

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1206-1216 doi: 10.1007/s11705-020-2017-7

摘要： In this work, the detailed oxygen reduction reaction (ORR) catalytic performance of M-N O (M= Fe, Co, and Ni; = 1–4) has been explored via the detailed density functional theory method. The results suggest that the formation energy of M-N O shows a good linear relationship with the number of doped O atoms. The adsorption manner of O on M-N O changed from end-on ( = 1 and 2) to side-on ( = 3 and 4), and the adsorption strength gradually increased. Based on the results for binding strength of ORR intermediates and the Gibbs free energy of ORR steps on the studied catalysts, we screened out two highly active ORR catalysts, namely Co-N O and Ni-N O , which possess very small overpotentials of 0.27 and 0.32 V, respectively. Such activities are higher than the precious Pt catalyst. Electronic structure analysis reveals one of the reasons for the higher activity of Co-N O and Ni-N O is that they have small energy gaps and moderate highest occupied molecular orbital energy levels. Furthermore, the results of the density of states reveal that the O doping can improve the electronic structure of the original catalyst to tune the adsorption of the ORR intermediates.

关键词： M-N-C catalyst     oxygen doping     oxygen reduction reaction     catalytic activity     density functional theory    

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Catalytic activity of manganese oxide supported on alumina in the synthesis of quinoxalines

Rekha M., H. Kathyayini, N. Nagaraju

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 415-421 doi: 10.1007/s11705-013-1360-3

摘要： Two catalysts, alumina and manganese oxide supported on alumina, have been prepared by calcination and precipitation-impregnation methods, respectively. The catalysts are characterised by the following techniques: Brunner-Emmett-Teller-N adsorption-desorption for surface area, temperature programmed desorption of NH and -butyl amine back titration methods for surface acidity, powder X-ray diffraction for textural properties, and Fourier transform infrared spectroscopy for the anionic radicals. The catalytic activity has been determined under heterogeneous conditions in the condensation reaction between -phenylenediamine and benzil. The product purity is checked by thin-layer chromatography and melting point. The products are also analysed by LC-MS and H-NMR techniques. The yields of the products have been found to be good and catalysts exhibited excellent recyclability. The effect of changing the reaction parameters such as temperature, reaction time, amount of the catalyst, nature of solvent and molar ratio of reactants on the yield of the product has been studied. The surface acidity of the catalysts plays an important role in activating the reaction.

关键词： alumina     manganese oxide deposited on alumina     quinoxaline synthesis    

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标题 作者 时间 类型 操作

Effect of a promoter on the methanation activity of a Mo-based sulfur-resistant catalyst

Can LIN, Haiyang WANG, Zhenhua LI, Baowei WANG, Xinbin MA, Shaodong QIN, Qi SUN

期刊论文

Cloning of human XAF1 gene promoter and assay of its transcription activity in a variety of cell lines

Qiong CHEN, Qing YU, Yuhu SONG, Peiyuan Li, Ying CHANG, Zhijun WANG, Lifeng LIU, Wei WU, Jusheng LIN

期刊论文

Construction, characterization and application of a genome-wide promoter library in

Ting Yuan,Yakun Guo,Junkai Dong,Tianyi Li,Tong Zhou,Kaiwen Sun,Mei Zhang,Qingyu Wu,Zhen Xie,Yizhi Cai,Limin Cao,Junbiao Dai

期刊论文

Osteopontin is a promoter for hepatocellular carcinoma metastasis: a summary of 10 years of studies

null

期刊论文

Distinct gene expression pattern of mutations coordinated by target repression and promoter hypermethylation

期刊论文

Effects of MgO promoter on properties of Ni/Al2O3 catalysts for partial oxidation of methane to syngas

QIU Yejun, CHEN Jixiang, ZHANG Jiyan

期刊论文

IDEEA activity monitor: validity of activity recognition for lying, reclining, sitting and standing

null

期刊论文

Production of pectic extracts from sugar beet pulp with antiproliferative activity on a breast cancer

Jacqueline CONCHA, Caroline WEINSTEIN, María Elvira Zú?IGA

期刊论文

Effect of 2-butenal manufacture wastewater to methanogenic activity and microbial community

Guangqing Song, Hongbo Xi, Xiumei Sun, Yudong Song, Yuexi Zhou

期刊论文

Low intensity ultrasound stimulates biological activity of aerobic activated sludge

LIU Hong, YAN Yixin, WANG Wenyan, YU Yongyong

期刊论文

A survey of physical activity among urban women in China

Shilin DENG MD, Tongyuan LIU,

期刊论文

preparation of Ag@AgCl/Bio-veins composites and their photocatalytic activity and recyclability

期刊论文

Antithrombin deficiency and decreased protein C activity in a young man with venous thromboembolism:

null

期刊论文

Probing the catalytic activity of M-N

Fan Ge, Qingan Qiao, Xin Chen, You Wu

期刊论文

Catalytic activity of manganese oxide supported on alumina in the synthesis of quinoxalines

Rekha M., H. Kathyayini, N. Nagaraju

期刊论文