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Identification and ecotoxicity assessment of intermediates generated during the degradation of clofibric acid by advanced oxidation processes

Wenzhen LI, Yu DING, Qian SUI, Shuguang LU, Zhaofu QIU, Kuangfei LIN

《环境科学与工程前沿（英文）》 2012年第6卷第4期页码 445-454 doi: 10.1007/s11783-012-0419-6

摘要： The aim of this study was to identify the intermediates in clofibric acid degradation under various advanced oxidation processes, namely ultraviolet (UV), UV/H O , vacuum ultraviolet (VUV), VUV/H O , and solar/TiO processes, as well as to assess the toxicity of these intermediates. Eleven intermediates have been detected by gas chromatography-mass spectrometer, most of which were reported for the first time to our best knowledge. Combining the evolution of the dissolved organic carbon, Cl and specific ultraviolet absorption at 254 nm, it could be deduced that cleavage of aromatic ring followed by dechlorination was the mechanism in solar/TiO process, while dechlorination happened first and accumulation of aromatic intermediates occurred in the other processes. Different transformation pathways were proposed for UV-, VUV-assisted and solar/TiO processes, respectively. The acute toxicity was evaluated by means of T spp. bioassay. It was believed that aromatic intermediates increased the toxicity and the ring-opening pathway in solar/TiO process could relieve the toxicity.

关键词： clofibric acid advanced oxidation processes intermediates toxicity Photobacterium phosphoreum T₃ spp.

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spp., foodborne pathogens threatening neonates and infants

Qiming CHEN, Yang ZHU, Zhen QIN, Yongjun QIU, Liming ZHAO

《农业科学与工程前沿（英文）》 2018年第5卷第3期页码 330-339 doi: 10.15302/J-FASE-2018208

摘要：

Cronobacter spp. (formerly Enterobacter sakazakii) are special foodborne pathogens. Cronobacter infection can cause necrotizing enterocolitis, sepsis and meningitis in all age groups, especially neonates and infants, with a high fatality of up to 80%, although the infection is rare. Outbreaks of Cronobacter infection are epidemiologically proven to be associated with contaminated powdered infant formula (PIF). Cronobacter spp. can resist dry environments and survive for a long period in food with low water activity. Therefore, Cronobacter spp. have become serious pathogens of neonates and infants, as well as in the dairy industry. In this review, we present the taxonomy, pathogenesis, resistance, detection and control of Cronobacter spp.

关键词： Cronobacter spp. desiccation resistance pathogen control pathogen detection powdered infant formula

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A CASE FOR ASSESSING ALLOCASUARINA AND CASUARINA SPP.

《农业科学与工程前沿（英文）》 2021年第8卷第4期页码 568-582 doi: 10.15302/J-FASE -2019270

摘要：

Agroecosystems in water-limited contexts— Mediterranean, semi-arid and arid climatic zones—are too frequently degraded systems that will not provide the needed ecosystem services to ensure a future of sustainable agricultural production. The processes that have created this situation continue and are being accelerated by anthropogenic climate change. Increasing arboreal vegetation in these areas through agroforestry is an important strategy to conserve and improve their agroecosystems. Actinorhizal trees and shrubs in the Casurinaceae have a unique set of adaptations for heat and water stress, and/or infertile to hostile soils. Central Anatolia, Turkey is particularly at risk of increasing aridity and further degradation. Therefore, species of Allocasuarina and Casuarina have been evaluated for their potential use in agroecosystem improvement in semi-arid areas with a focus on Central Anatolia. Based on a semiquantitative environmental tolerance index and reported plant stature, eight species were identified as being of high (A. verticillata and C. pauper) to moderate (A. acutivalvis, A. decaisneana, A. dielsiana, A. huegeliana, C. cristata and C. obesa) priority for assessment, with none of these species having been adequately evaluated for agroforestry deployment in semi-arid agroecosystems in any context.

关键词： actinorrhizal trees / agroforestry / climate change / ecosystem restoration

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Repeats in the transcribed regions: comprehensive characterization and comparison of

Manosh Kumar BISWAS, Christoph MAYER, Xiuxin DENG

《农业科学与工程前沿（英文）》 2017年第4卷第4期页码 421-432 doi: 10.15302/J-FASE-2017160

摘要： A large number of expressed sequences tags are available for spp., which provides an opportunity to understand genomic organization of the transcribed regions. Here, we report a detailed analysis of repetitive elements including tandem repeats (TRs) and transposable elements (TEs) in the transcribed region of the spp. On average, 22% of the expressed sequence tags (ESTs) contain TRs. The relative density of TR classes is highly taxon-specific. For instance, has a high relative density of mononucleotide repeats, whereas dinucleotide repeats are rare. The proportions of 2–6, 7–30 and 31–50 bp repeats were almost identical in all studied species except for and . We found that<1% of the citrus ESTs have a similarity with transposable elements. Transcriptional activity of transposable element families varied even within the same class of elements. A high proportion of transcriptional activity was observed for -like TEs compare to other TE classes. While TEs are relatively rare, TRs are abundant elements in ESTs of citrus. The high proportion of TRs that have a unit size longer than 6 bp raises the question about a possible functional or evolutionary role of these elements.

关键词： Citrus spp. tandem repeats transcribed region transposable elements

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CRISPR-Cas9 mediated LAG-3 disruption in CAR-T cells

null

《医学前沿（英文）》 2017年第11卷第4期页码 554-562 doi: 10.1007/s11684-017-0543-6

摘要：

T cells engineered with chimeric antigen receptor (CAR) have been successfully applied to treat advanced refractory B cell malignancy. However, many challenges remain in extending its application toward the treatment of solid tumors. The immunosuppressive nature of tumor microenvironment is considered one of the key factors limiting CAR-T efficacy. One negative regulator of T cell activity is lymphocyte activation gene-3 (LAG-3). We successfully generated LAG-3 knockout T and CAR-T cells with high efficiency using CRISPR-Cas9 mediated gene editing and found that the viability and immune phenotype were not dramatically changed during in vitro culture. LAG-3 knockout CAR-T cells displayed robust antigen-specific antitumor activity in cell culture and in murine xenograft model, which is comparable to standard CAR-T cells. Our study demonstrates an efficient approach to silence immune checkpoint in CAR-T cells via gene editing.

关键词： CAR-T CRISPR-Cas9 LAG-3

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Influence and related mechanism of Retn gene expression on glucose uptake in 3T3-L1 cells

LI Yahui, DONG Shiyuan, YU Chao, JIANG Yu, LI Huaixing, SUN Shuhan

《医学前沿（英文）》 2007年第1卷第3期页码 269-273 doi: 10.1007/s11684-007-0051-1

摘要： The aim of this article was to investigate the influence and the related mechanism of the gene on glucose uptake and insulin resistance in 3T3-L1 cells. Radioimmunoassay was used to determine glucose uptake in 3T3-L1 cells with different gene expression levels, whether cells were stimulated by insulin or not. RT-PCR and real-time RT-PCR analysis were used to determine the mRNA levels of several glucose transport proteins in 3T3-L1 cells with different gene expression levels, including insulin receptor substrate-1(IRS-1), phosphatidylinositol 3-kinase (PI-3K), AKT-2, glucose transporter-4 (GLUT-4), p38 mitogen-activated protein kinase (p38MAPK) and glycogen synthase kinase-3b (GSK-3). The glucose uptake decreased with the increase in gene expression in 3T3-L1 cells, which was independent of whether the cells were stimulated by insulin or not. The mRNA expression of two signal proteins PI-3K and AKT-2 decreased and the other two signal proteins, GSK-3 and p38MAPK, increased with overexpression in 3T3-L1 cells. Resistin could induce insulin resistance in adipocytes, which might be related to the changes of some proteins in PI-3K and Ras pathways.

关键词： 3T3-L1 influence resistance receptor substrate-1 transport

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Novel mutation c.1210-3C>G in with a poly-T tract of 5T affects mRNA splicing in a Chinese patient

《医学前沿（英文）》 2022年第16卷第1期页码 150-155 doi: 10.1007/s11684-021-0846-5

摘要： Cystic fibrosis (CF) is a rare autosomal recessive disease with only one pathogenic gene cystic fibrosis transmembrane conductance regulator (CFTR). To identify the potential pathogenic mutations in a Chinese patient with CF, we conducted Sanger sequencing on the genomic DNA of the patient and his parents and detected all 27 coding exons of CFTR and their flanking intronic regions. The patient is a compound heterozygote of c.2909G>A, p.Gly970Asp in exon 18 and c.1210-3C>G in cis with a poly-T of 5T (T5) sequence, 3 bp upstream in intron 9. The splicing effect of c.1210-3C>G was verified via minigene assay in vitro, indicating that wild-type plasmid containing c.1210-3C together with T7 sequence produced a normal transcript and partial exon 10-skipping-transcript, whereas mutant plasmid containing c.1210-3G in cis with T5 sequence caused almost all mRNA to skip exon 10. Overall, c.1210-3C>G, the newly identified pathogenic mutation in our patient, in combination with T5 sequence in cis, affects the CFTR gene splicing and produces nearly no normal transcript in vitro. Moreover, this patient carries a p.Gly970Asp mutation, thus confirming the high-frequency of this mutation in Chinese patients with CF.

关键词： cystic fibrosis CFTR splicing mutation minigene

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Changes of phenotype and function of human CD4 CD25 T cells induced by transfection of Foxp3

WU Kui, BI Yutian, WANG Yaoli, WANG Changzheng

《医学前沿（英文）》 2008年第2卷第4期页码 366-369 doi: 10.1007/s11684-008-0070-6

摘要： The aim of this paper is to explore the effects of transfection of Foxp3 gene on the phenotype and function of naive CD4 T cells. The pMSCV-Foxp3 retroviral vector encoding Foxp3 gene was transduced into the PT67 packaging cell line. Virus-containing supernatant was applied to differentiate CD4CD25 T cells. The resulting cells were sorted with flow cytometry. The expressions of CD25, CD127, CTLA-4 and the proliferation of transfected T cells were examined. The effect of transfected CD4 T cells on the proliferation and cytokine production of CD4CD25 T cells was examined. Foxp3-gene transfected CD4 T cells could express Foxp3 and transfection of Foxp3 gene up-regulated the expressions of CD25 and CTLA-4, but down-regulated CD127 expression. After transfection, the proliferation of CD4 T cells was eliminated. Transfected T cells inhibited the proliferation of CD4CD25 T cells. CD4CD25 T cells acquired a regulatory phenotype and function after it was transduced with the Foxp3 gene. This suggested a key role of Foxp3 in the generation of CD4CD25 regulatory T cells.

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randomized trials of maintenance bacillus Calmette-Guerin instillation efficacy against recurrence of T1G3

PAN Jiangang, ZHOU Xing, CHEN Zhiguang, HAN Ruifa

《医学前沿（英文）》 2008年第2卷第3期页码 259-263 doi: 10.1007/s11684-008-0049-3

摘要： Meta-analysis was used to determine whether maintenance intravesical bacillus Calmette-Guerin (BCG) could reduce recurrence after transurethral resection of tumor 1 grade 3 (T1G3) superficial bladder cancer. All available published data of randomized clinical trials comparing transurethral resection plus intravesical BCG to either resection alone or resection plus another treatment on the treatment results in patients with superficial bladder cancer of T1G3 were selected for analysis. Both the fixed effects model and random effects model were applied, and the odds ratio () with its 95% confidence interval (CI) was used as the effect size estimate. Sensitivity analysis and publication bias determination were performed by funnel plots and comparing s of different models. Within the follow-up period, 375 of 915 (41.0%) BCG-treated patients and 332 of 733 (45.3%) non-BCG-treated patients developed tumor recurrence. In the combined results, a statistically significant difference in the s for tumor recurrence between the two treatment groups was found (randomized model combined effect 0.58, 95% CI 0.41 to 0.83, = 0.003). The stratified meta-analysis did not show any statistically significant confounding effects on the results when stratified by BCG strains. The randomized model combined effect of Pasteur F and other strains were 0.50 (95% CI 0.26 to 0.95, = 0.04) and 0.63 (95% CI 0.40 to 0.99, = 0.04), respectively. Therefore, we came to the conclusion that adjuvant maintenance instillation BCG combined with transurethral resection of bladder tumor (TURBT) is an effective conservative treatment for preventing recurrence of T1G3 bladder cancer.

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作为免疫疗法靶点的FOXP3及其辅因子 Review

Yasuhiro Nagai,Lian Lam,Mark I. Greene,Hongtao Zhang

《工程（英文）》 2019年第5卷第1期页码 115-121 doi: 10.1016/j.eng.2019.01.001

摘要：

叉头框蛋白P3（FOXP3）是调节性T细胞（Tregs）的一个主要调节因子，调节性T细胞是能抑制抗原特异性免疫反应的T 细胞亚群，在增强宿主耐受性和维持免疫平衡方面发挥着重要作用。众所周知，FOXP3 与多种蛋白质形成复合物，并能通过乙酰化、磷酸化、泛素化和甲基化等各种翻译后修饰（PTM）进行调节。因此，翻译后修饰可改变FOXP3 的稳定性及其调节基因表达的能力，并最终影响调节性T细胞活性。虽然FOXP3 自身并非理想的药物靶点，但脱乙酰酶、乙酰转移酶、激酶和其他可调节FOXP3 的翻译后修饰的酶均为调控FOXP3 和调节性T细胞活性的潜在靶点。但FOXP3 并非这些酶的唯一底物；因此，当使用相关抑制剂时，必须考虑是否存在有害的“FOXP3脱靶”副作用。

关键词：调节性T细胞叉头框蛋白P3（FOXP3）翻译后修饰自体免疫癌症

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Ductile extension of 3-D external circumferential cracks in pipe structures

Wuchao YANG, Xudong QIAN

《结构与土木工程前沿（英文）》 2011年第5卷第3期页码 294-303 doi: 10.1007/s11709-011-0115-9

摘要： This study investigates the ductile fracture resistance of 3-D external circumferential cracks in the wall of a steel pipe under remote tension, using a damage-mechanism model originally proposed by Gurson and Tvergaard. The ductile crack extension utilizes an element extinction technique implemented in the computational cell framework. The key parameter for the computational cell method, i.e., the initial porosity ratio , is calibrated using both the fracture resistance and the load-deformation responses obtained from fracture tests of multiple single-edge bend [SE(B)] specimens made of high-strength steel, HY80, which has a yield strength of 630 MPa. The fracture resistance along the 3-D semi-elliptical crack front is computed from the calibrated cell model. Based on the similarity concept in the near-tip stress-strain fields, this study demonstrates that an equivalent 2-D axi-symmetric model provides conservative estimations of the fracture resistance for 3-D circumferential cracks in pipes.

关键词： ductile fracture computational cell method G-T model J-R curve

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募集抗原特异性T细胞的3D打印支架促进血管化 Article

李翠笛, 马振江, 李文韬, 颉天阳, 钟丽萍, 陈宏方, 王文豪, 王金武, 崔文国, 赵永祥

《工程（英文）》 2022年第17卷第10期页码 183-195 doi: 10.1016/j.eng.2021.05.018

摘要：

3D打印支架植入后激起的免疫反应是组织修复效果的主要决定性因素。因此，巧妙调控免疫反应的支架材料具有高效修复组织的潜能。本研究受抗原特异性免疫反应对血管新生促进作用的启发，通过动态共价键将介孔二氧化硅微棒（MSR）/聚乙烯亚胺（PEI）/卵清蛋白（OVA）自组装疫苗与3D打印自固化磷酸钙骨水泥（CPC）基支架结合，构建了一种具有调控局部体液免疫反应功能的组织修复支架通过局部释放OVA激活体液免疫反应，支架可有效募集抗原特异性CD4⁺ 2 型辅助性T细胞（Th2 细胞），从而促进支架植入早期的血管新生；在提供充足和丰富的血供环境的同时，MSR微棒中释放的硅离子还能有效加速骨再生在皮下包埋实验中，疫苗负载支架增加了Th2 细胞在脾脏中的比例，局部募集了抗原特异性T细胞并促进了支架内的血管新生。此外，原位颅骨缺损修复模型结果表明，负载疫苗的支架可促进血管化骨组织再生。

关键词： 3D打印免疫微环境调控血管新生骨再生

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An extended cell-based smoothed discrete shear gap method (XCS-FEM-DSG3) for free vibration analysis

Dang-TRUNG,T. NGUYEN-THOI

《结构与土木工程前沿（英文）》 2015年第9卷第4期页码 341-358 doi: 10.1007/s11709-015-0302-1

摘要： A cell-based smoothed discrete shear gap method (CS-FEM-DSG3) was recently proposed and proven to be robust for free vibration analyses of Reissner-Mindlin shell. The method improves significantly the accuracy of the solution due to softening effect of the cell-based strain smoothing technique. In addition, due to using only three-node triangular elements generated automatically, the CS-FEM-DSG3 can be applied flexibly for arbitrary complicated geometric domains. However so far, the CS-FEM-DSG3 has been only developed for analyzing intact structures without possessing internal cracks. The paper hence tries to extend the CS-FEM-DSG3 for free vibration analysis of cracked Reissner-Mindlin shells by integrating the original CS-FEM-DSG3 with discontinuous and crack−tip singular enrichment functions of the extended finite element method (XFEM) to give a so-called extended cell-based smoothed discrete shear gap method (XCS-FEM-DSG3). The accuracy and reliability of the novel XCS-FEM-DSG3 for free vibration analysis of cracked Reissner-Mindlin shells are investigated through solving three numerical examples and comparing with commercial software ANSYS.

关键词： cracked Reissner-Mindlin shell free vibration analysis cell-based smoothed discrete shear gap method (CS-FEM-DSG3) extended cell-based smoothed discrete shear gap method (XCS-FEM-DSG3) smoothed finite element methods (SFEM)

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Interactions between metal ions and the biopolymer in activated sludge: quantification and effects of system pH value

Yun Zhou, Siqing Xia, Binh T. Nguyen, Min Long, Jiao Zhang, Zhiqiang Zhang

《环境科学与工程前沿（英文）》 2017年第11卷第1期 doi: 10.1007/s11783-017-0898-6

摘要： The biopolymer showed two protein-like fluorescence peaks (peaks A and B). Interactions of Pb(II) and biopolymer were quantified at various system pH values. System pH values significantly affect the quenching constant values for both peaks. Peak B plays a more important role in the interactions than peak A. Removal mechanism of metal ions by activated sludge system was further disclosed. The quantification and effects of system pH value on the interactions between Pb(II) and the biopolymer from activated sludge were investigated. The biopolymer had two protein-like fluorescence peaks (Ex/Em= 280 nm/326–338 nm for peak A; Ex/Em= 220–230 nm/324–338 nm for peak B). The fluorescence intensities of peak B were higher than those of peak A. The fluorophores of both peaks could be largely quenched by Pb(II), and the quencher dose for peak B was about half of that for peak A. The modified Stern-Volmer equation well depicted the fluorescence quenching titration. The quenching constant (Ka) values for both peaks decreased with rising system pH value, and then sharply decreased under alkaline conditions. It could be attributed to that the alkaline conditions caused the reduction of available Pb(II) due to the occurrence of Pb(OH)2 sediments. The Ka values of peak B were bigger than those for peak A at the same system pH values. Accordingly, the aromatic protein (peak B) plays the key role in the interactions between metal ions and the biopolymer.

关键词： Metal ions Biopolymer Activated sludge Three-dimensional excitation emission matrix (3D-EEM) Fluorescence regional integration (FRI) technique Quantification

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3D finite element prediction of chip flow, burr formation, and cutting forces in micro end-milling ofaluminum 6061-T6

A. DAVOUDINEJAD, P. PARENTI, M. ANNONI

《机械工程前沿（英文）》 2017年第12卷第2期页码 203-214 doi: 10.1007/s11465-017-0421-6

摘要：

Predictive models for machining operations have been significantly improved through numerous methods in recent decades. This study proposed a 3D finite element modeling (3D FEM) approach for the micro end-milling of Al6061-T6. Finite element (FE) simulations were performed under different cutting conditions to obtain realistic numerical predictions of chip flow, burr formation, and cutting forces. FE modeling displayed notable advantages, such as capability to easily handle any type of tool geometry and any side effect on chip formation, including thermal aspect and material property changes. The proposed 3D FE model considers the effects of mill helix angle and cutting edge radius on the chip. The prediction capability of the FE model was validated by comparing numerical model and experimental test results. Burr dimension trends were correlated with force profile shapes. However, the FE predictions overestimated the real force magnitude. This overestimation indicates that the model requires further development.

关键词： 3D finite element modeling micro end-milling cutting force chip formation burr formation