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CO2利用 1

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微生物电化学技术 1

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胞外电子传递 1

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Development of a dual temperature control system for isoprene biosynthesis in

《化学科学与工程前沿(英文)》 2022年 第16卷 第7期   页码 1079-1089 doi: 10.1007/s11705-021-2088-0

摘要: Conflict between cell growth and product accumulation is frequently encountered in the biosynthesis of secondary metabolites. To address the growth-production conflict in yeast strains harboring the isoprene synthetic pathway in the mitochondria, the dynamic control of isoprene biosynthesis was explored. A dual temperature regulation system was developed through engineering and expression regulation of the transcriptional activator Gal4p. A cold-sensitive mutant, Gal4ep19, was created by directed evolution of Gal4p based on an internally developed growth-based high-throughput screening method and expressed under the heat-shock promoter PSSA4 to control the expression of PGAL-driven pathway genes in the mitochondria. Compared to the control strain with constitutively expressed wild-type Gal4p, the dual temperature regulation strategy led to 34.5% and 72% improvements in cell growth and isoprene production, respectively. This study reports the creation of the first cold-sensitive variants of Gal4p by directed evolution and provides a dual temperature control system for yeast engineering that may also be conducive to the biosynthesis of other high-value natural products.

关键词: transcriptional activator     directed evolution     dynamic control     heat-shock     isoprene    

The development of ultralightweight expanded perlite-based thermal insulation panel using alkali activator

Damla Nur ÇELİK; Gökhan DURMUŞ

《结构与土木工程前沿(英文)》 2022年 第16卷 第11期   页码 1486-1499 doi: 10.1007/s11709-022-0881-6

摘要: The International Energy Agency (IEA) states that global energy consumption will increase by 53% by 2030. Turkey has 70% of the world’s perlite reserves, and in order to reduce energy consumption a thermal insulation panel was developed in Turkey using different particle sizes of expanded perlite (EP). In this study, 0–1.18 mm (powder) and 0–3 mm (granular) EP particle sizes were selected, since they have the lowest thermal conductivity coefficients among all the particle sizes. In addition, an alkali activator solution was used as a binder in the mixtures. The alkaline activator solution was obtained by mixing sodium hydroxide solution (6, 8, 10, and 12 mol·L−1) and sodium silicate (Module 3) at the different ratios of Na2SiO3 to NaOH of 1, 1.5, 2, and 2.5. This study aimed to experimentally determine the optimum binder and distribution ratio of EP, with the lowest coefficient of thermal conductivity and the lowest density. The lowest thermal conductivity and the lowest density were determined as 0.04919 W·m−1·K−1 and 133.267 kg/m3, respectively, in the sample prepared with 83.33% powder-size EP, 6 mol·L−1 sodium hydroxide solution, and ratio of Na2SiO3 to NaOH of 1.5. The density, thermal conductivity, and compressive strength of the sample showed the same trends of behavior when the Na2SiO3 to NaOH ratio was increased. In addition, the highest compressive strength was measured in 12 mol·L−1 NaOH concentration regardless of particle size. In conclusion, the study predicts that the EP-based thermal insulation panel can be used as an insulation material in the construction industry according to the TS825 Thermal Insulation Standard.

关键词: expanded perlite     alkali activator     thermal insulation panel     thermal conductivity    

Chemotactic effect of urokinase-type plasminogen activator on mouse spermatozoa

DING Xiaofang, LI Honggang, XIONG Chengliang

《医学前沿(英文)》 2008年 第2卷 第2期   页码 195-199 doi: 10.1007/s11684-008-0037-7

摘要: The aim of this study is to investigate the chemotactic effect of urokinase-type plasminogen activator (uPA) on mouse spermatozoa. Capillary assays were applied to study the chemotactic activity of ascending and descending gradients of uPA. Firstly, the chemotactic effect of an ascending gradient of uPA on mouse spermatozoa was observed by counting the number of spermatozoa that migrated into the capillary after incubation with uPA for 5, 10, 20, and 30 min, respectively, compared with that after incubation with F10. Twenty minutes was a suitable incubation time to obtain a plateau of sperm accumulation. Meanwhile, to confirm the specific effect of uPA on mouse sperm chemotaxis, uPA inhibitor (PAI-1) and anti-uPAR rabbit IgG were added to the test solution containing 20 U/mL uPA, respectively. To exclude the possibility that PAI-1 and anti-uPAR rabbit IgG may affect sperm accumulation nonspecifically, PAI-1 and anti-uPAR rabbit IgG were added to F10, respectively. It was found that the chemotactic effect of uPA was neutralized completely by PAI-1 and anti-uPAR rabbit IgG. PAI-1 and anti-uPAR rabbit IgG had no neutralizing effect on the sperm chemotactic effect. Lastly, the sperm chemotaxis response to a descending gradient of uPA was also observed. Taken together, the results suggest that uPA can induce sperm chemotaxis by binding to its receptor on the sperm membrane and may act as a chemoattractant in precontacting sperm-egg communication thereby increasing the chance encounter of spermatozoa and eggs.

关键词: chemotactic activity     receptor     uPA inhibitor     F10     chemoattractant    

Transcriptional modules related to hepatocellular carcinoma survival: coexpression network analysis

null

《医学前沿(英文)》 2016年 第10卷 第2期   页码 183-190 doi: 10.1007/s11684-016-0440-4

摘要:

We performed weighted gene coexpression network analysis (WGCNA) to gain insights into the molecular aspects of hepatocellular carcinoma (HCC). Raw microarray datasets (including 488 samples) were downloaded from the Gene Expression Omnibus (GEO) website. Data were normalized using the RMA algorithm. We utilized the WGCNA to identify the coexpressed genes (modules) after non-specific filtering. Correlation and survival analyses were conducted using the modules, and gene ontology (GO) enrichment was applied to explore the possible mechanisms. Eight distinct modules were identified by the WGCNA. Pink and red modules were associated with liver function, whereas turquoise and black modules were inversely correlated with tumor staging. Poor outcomes were found in the low expression group in the turquoise module and in the high expression group in the red module. In addition, GO enrichment analysis suggested that inflammation, immune, virus-related, and interferon-mediated pathways were enriched in the turquoise module. Several potential biomarkers, such as cyclin-dependent kinase 1 (CDK1), topoisomerase 2α (TOP2A), and serpin peptidase inhibitor clade C (antithrombin) member 1 (SERPINC1), were also identified. In conclusion, gene signatures identified from the genome-based assays could contribute to HCC stratification. WGCNA was able to identify significant groups of genes associated with cancer prognosis.

关键词: hepatocellular carcinoma     coexpression     module     microarray     prognosis    

Distinct gene expression pattern of mutations coordinated by target repression and promoter hypermethylation in acute myeloid leukemia

《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    

Assessment and prediction of the mechanical properties of ternary geopolymer concrete

Jinliang LIU; Wei ZHAO; Xincheng SU; Xuefeng XIE

《结构与土木工程前沿(英文)》 2022年 第16卷 第11期   页码 1436-1452 doi: 10.1007/s11709-022-0889-y

摘要: This paper utilized granulated blast furnace slag (GBFS), fly ash (FA), and zeolite powder (ZP) as the binders of ternary geopolymer concrete (TGC) activated with sodium silicate solution. The effects of alkali content (AC) and alkaline activator modulus (AAM) on the compressive strength, flexural tensile strength and elastic modulus of TGC were tested and the SEM micrographs were investigated. The experimental results were then compared with the predictions based on models of mechanical properties, and the amended models of TGC were proposed taking account of the effects of AC and AAM. The results indicated that increasing AC and reducing AAM which were in the specific ranges (5% to 7% and 1.1 to 1.5, respectively) had positive effects on the mechanical properties of TGC. In addition, the flexural tensile strength of TGC was 27.7% higher than that of OPC at the same compressive strength, while the elastic modulus of TGC was 25.8% lower than that of OPC. Appropriate prediction models with the R2 of 0.945 and 0.987 for predicting flexural tensile strength and elastic modulus using compressive strength, respectively, were proposed. Fitting models, considering the effects of AC and AAM, were also proposed to predict the mechanical properties of TGC.

关键词: Ternary Geopolymer Concrete (TGC)     alkaline activator modulus     alkali content     mechanical properties     assessment    

Clinical and genetic risk factors for venous thromboembolism in Chinese population

Chen WANG PhD, MD, Zhen-Guo ZHAI PhD, MD, Ying H. SHEN PhD, MD, Lan ZHAO PhD, MD,

《医学前沿(英文)》 2010年 第4卷 第1期   页码 29-35 doi: 10.1007/s11684-010-0012-y

摘要: Venous thromboembolism (VTE), including deep vein thrombosis and pulmonary embolism, carries significant mortality and morbidity. The most important and effective way to reduce VTE incidence is to identify the patients at risk and give necessary prevention. VTE is a multifactorial and complicated disorder. Major risk factors for VTE include surgery and trauma, acute medical illness, active cancer and pregnancy. Genetic factors increase susceptibility to the disease and are useful in predicting the development of VTE. Gene-gene and gene-environment interactions alter and magnify the clinical picture in this disorder. This brief review summarizes some selected clinical and genetic risk factors for VTE based on the current research in China.

关键词: risk factor     stroke     prothrombin     plasminogen activator inhibitor type-1     polymorphism     thrombophilia     biomarker    

Dysregulation of β-catenin by hepatitis B virus X protein in HBV-infected human hepatocellular carcinomas

Lei CHEN, Liang HU, Liang LI, Yuan LIU, Qian-Qian TU, Yan-Xin CHANG, He-Xin YAN, Meng-Chao WU, Hong-Yang WANG,

《医学前沿(英文)》 2010年 第4卷 第4期   页码 399-411 doi: 10.1007/s11684-010-0170-y

摘要: β-catenin is a key molecule involved in both cell-cell adhesion and Wnt signaling pathway. In our study, we found that, in the development of hepatocellular carcinoma (HCC), β-catenin was correlated with hepatitis B virus (HBV) X gene encoded protein, which is essential for HBV infectivity and is a potential cofactor in viral carcinogenesis. The expression levels of wild-type β-catenin and E-cadherin were decreased in HepG2 cells expressing hepatitis B virus X protein (HBx), accompanied by destabilization of adherens junction. Reverse transcriptase PCR (RT-PCR), Northern and Western blot showed that reduction of wild-type β-catenin expression involved degradation of the protein. However, RNA interference (RNAi) and luciferase assay indicated that HBx enhanced β-catenin mediated signaling in HepG2 cells. In addition, immunohistochemical and Western blot analysis of β-catenin revealed that a decrease in the β-catenin protein level was found in 58.3% of HBV-related HCCs 19.2% of non-HBV-related tumors. Our data suggest that the expression of HBx contributed to the development of HCC, in part, by repressing the wild-type β-catenin expression and enforcing β-catenin-dependent signaling pathway, thus inducing cellular changes leading to acquisition of metastatic and/or proliferation properties.

关键词: hepatocellular carcinoma     hepatitis B virus X protein     β     -catenin     cell adhesion     E-cadherin     transcriptional activation    

Expression of STAT6 and NF-κB p65 in the colon mucosa of patients with ulcerative colitis

Rui ZHU MD, Heng FAN MD, Lin SHEN MD, Jianguo LIU BD, Jia ZHAO MM,

《医学前沿(英文)》 2009年 第3卷 第4期   页码 475-479 doi: 10.1007/s11684-009-0086-6

摘要: The expression of signal transducer and activator of transcription 6 (STAT6) and nuclear factor-κB (NF-κB) in the colonic mucosa of patients with ulcerative colitis (UC) was examined. Real-time polymerase chain reaction and immunohistochemistry were used to detect the expression of STAT6 and NF-κB p65 at both mRNA and protein levels in the colonic mucosa of patients with UC and healthy volunteers. The results showed that the expression levels of STAT6 and NFκB p65 in the colonic mucosa of patients with UC were significantly higher than in normal controls at both mRNA and protein levels. These data suggest that STAT6 and NFκB p65 perhaps play an important role in the pathogenesis of UC and underscore the potential value of anti-UC strategies in the clinical management of this disease.

关键词: ulcerative colitis     signal transducer and activator of transcription 6 (STAT6)     nuclear factor-κ     B p65 (NF-κ     B p65)    

流动电极微生物电合成提高产物生成速率及降低能量消耗 Article

褚娜, 王东麟, 王厚锋, 梁勤军, 常佳丽, 高瑜, 蒋永, 曾建雄

《工程(英文)》 2023年 第25卷 第6期   页码 157-167 doi: 10.1016/j.eng.2021.09.015

摘要:

微生物电合成(microbial electrosynthesis, MES)利用可再生电力驱动微生物固定CO2合成化学品,在推进碳循环经济中具有一定潜力,受到广泛关注。但是,很少有研究通过高效反应器设计来促进产乙酸并降低能耗。本研究中,新型流动电极MES反应器的总产乙酸速率[(16 ± 1) g·m−2·d−1]比无粉末活性炭(powder activated carbon, PAC)对照[(8 ± 3) g·m−2·d−1]高两倍。流动电极MES反应器的库伦效率为43.5% ± 3.1%,能量消耗为(0.020 ± 0.005) kWh·g−1,产乙酸的能量效率为18.7% ± 1.3%。基于PAC的流动电极能够降低水跨膜通量、传质阻力,但是对装置电压、流变行为、乙酸吸附的影响较小。流动电极MES反应器中,能量代谢相关基因高表达,Acetobacterium的丰度增加。MES反应器中同时存在用于碳固定的还原性乙酰辅酶A途径(Wood–Ljungdahl pathway, WLP)与还原性三羧酸循环途径(reductive citric acid cycle, rTCA)。堆叠型流动电极MES中的乙酸浓度达7.0 g·L−1。本研究提供一种构建可扩展MES反应器的新方法,促进CO2利用以及产物生成。

关键词: CO2利用     生物阴极     宏转录组     微生物电化学技术     胞外电子传递    

Effect of compound Sophorae Flavescentis Jiechangrong capsule on expression of NF-κB p65 and STAT6 in the intestinal mucosa of patients with ulcerative colitis

Heng FAN MD, Jia ZHAO MM, Lin SHEN BM, Qing TANG MD, Zhexin SHOU MM, Li LIANG BM, Yi LIAO BM, Xiaoyan CHEN BM,

《医学前沿(英文)》 2009年 第3卷 第4期   页码 480-484 doi: 10.1007/s11684-009-0083-9

摘要: The effects of compound Sophorae Flavescentis Jiechangrong capsule (CSFJC) on the expression of nuclear factor-κB p65 (NF-κB p65) and signal transducer and activator of transcription 6 (STAT6) in the intestinal mucosa of patients with ulcerative colitis and the possible mechanism were investigated. Eighteen patients with ulcerative colitis were randomly divided into a traditional Chinese medicine (TCM) group ( = 11) treated by CSFJC and a western medicine (WM) group ( = 7) treated by Sulfasalazine tablets. The treatment duration lasted eight weeks. Before and after the treatment, the symptoms and the physical signs were observed, and the routine stool test, the colonoscopy, and pathological examination were performed in the two groups. The expression levels of NF-κBp65 and STAT6 were detected by using immunohistochemistry. The results showed that the total effective rate of the curative effectiveness in TCM and WM groups was 100% and 71.4%, respectively, and the total effective rate of colonic mucosa lesion in TCM and WM groups was 90.9% and 71.4%, respectively, with the differences being significant (all < 0.05). The total effective rate of syndromes of damp-heat blocking according to the TCM in TCM and WM groups was 90.9% and 71.4%, respectively. After the treatment, the expression of NF-κB p65 and STAT6 in the two groups was decreased, and the decrease of NF-κB p65 and STAT6 expression in TCM group was more significant than in WM group ( < 0.05). It was concluded that CSFJC can inhibit the activation and expression of NF-κB p65 and STAT6 in the intestinal mucosa of patients with ulcerative colitis, which is a possible mechanism for CSFJC treating ulcerative colitis.

关键词: colitis     ulcerative     compound Sophorae Flavescentis Jiechangrong capsule     nuclear factor-κ     B p65 (NF-κ     B p65)     signal transducer and activator of transcription 6 (STAT6)    

标题 作者 时间 类型 操作

Development of a dual temperature control system for isoprene biosynthesis in

期刊论文

The development of ultralightweight expanded perlite-based thermal insulation panel using alkali activator

Damla Nur ÇELİK; Gökhan DURMUŞ

期刊论文

Chemotactic effect of urokinase-type plasminogen activator on mouse spermatozoa

DING Xiaofang, LI Honggang, XIONG Chengliang

期刊论文

Transcriptional modules related to hepatocellular carcinoma survival: coexpression network analysis

null

期刊论文

Distinct gene expression pattern of mutations coordinated by target repression and promoter hypermethylation in acute myeloid leukemia

期刊论文

Assessment and prediction of the mechanical properties of ternary geopolymer concrete

Jinliang LIU; Wei ZHAO; Xincheng SU; Xuefeng XIE

期刊论文

Clinical and genetic risk factors for venous thromboembolism in Chinese population

Chen WANG PhD, MD, Zhen-Guo ZHAI PhD, MD, Ying H. SHEN PhD, MD, Lan ZHAO PhD, MD,

期刊论文

Dysregulation of β-catenin by hepatitis B virus X protein in HBV-infected human hepatocellular carcinomas

Lei CHEN, Liang HU, Liang LI, Yuan LIU, Qian-Qian TU, Yan-Xin CHANG, He-Xin YAN, Meng-Chao WU, Hong-Yang WANG,

期刊论文

Expression of STAT6 and NF-κB p65 in the colon mucosa of patients with ulcerative colitis

Rui ZHU MD, Heng FAN MD, Lin SHEN MD, Jianguo LIU BD, Jia ZHAO MM,

期刊论文

流动电极微生物电合成提高产物生成速率及降低能量消耗

褚娜, 王东麟, 王厚锋, 梁勤军, 常佳丽, 高瑜, 蒋永, 曾建雄

期刊论文

Effect of compound Sophorae Flavescentis Jiechangrong capsule on expression of NF-κB p65 and STAT6 in the intestinal mucosa of patients with ulcerative colitis

Heng FAN MD, Jia ZHAO MM, Lin SHEN BM, Qing TANG MD, Zhexin SHOU MM, Li LIANG BM, Yi LIAO BM, Xiaoyan CHEN BM,

期刊论文