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Aggregation Behavior and Structure of Associated Polyacrylamide Hydrophobically Modified with 2-Phenoxylethylacrylate

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Chemical Research in Chinese Universities 2009年第6期25卷 957-962页

作者： DAI Yu-hua WU Fei-peng LI Miao-zhen wang er-jian Department of Materials Science and Engineering Beijing Institute of Petrochemical Technology Beijing 102617 P. R. China Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100101 P. R. China

The aggregation behavior and structure of hydrophobically modified block copolymers of acrylamide and 2-phenoxylethylacrylate were investigated by viscometry, 1H NMR relaxation, 2D NOESY, fluorescence and dynamic light scattering. It Was found that the aggregation behavior was strongly dependent on the concentration of polymer solution and the hydrophobe contents. With varying concentration from 2.0, 6.0, 8.0 to 12.0 g/L, there were different aggregate morphologies distributed in aqueous solutions, such as monopolymer chain, micelle-like aggregate, multi-micelle aggregate and cross-linked network. According to the model of aggregation, it can give a reasonable explanation on the large magnitude enhancement of viscosity with the increasing of polymer concentration. Additional data of 2D NOESY and fluorescence show that the copolymer with higher hydrophobe content（molar fraction≥ 1%） is likely to form intra-molecular association.

关键词： Aggregation behavior and structure Hydrophobically modified Copolymer P(AM/POEA)

Changes in Temporal Concentration Property of Summer Precipitation in China during 1961–2010 Based on a New Index

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Journal of Meteorological Research 2017年第2期31卷 336-349页

作者： Hui LI Panmao ZHAI er LU Wei ZHAO Yang CHEN Huan wang Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science&TechnologyNanjing 210044 Chinese Academy of Meteorological Sciences Beijing 100081

Based on the property of entropy,a new index Q was defined to measure the temporal concentration property of summertime daily rainfall in China,based on daily precipitation data collected at 553 observation stations in China during 1961–***,changes in the temporal concentration property of summer precipitation in China were *** results indicate that the regions with larger Q values were located in most parts of Northwest China and the north of the Yellow River,where daily precipitation tended to become temporally concentrated during the study *** the contrary,smaller Q values were found in eastern Tibetan Plateau,southeastern Northwest China,and most parts of Southwest and South *** most obvious increasing trend of Q index was found in South China and most parts of Southwest China,where precipitation showed a temporal concentration ***,a decreasing trend of Q index was found in Northwest China,the Tibetan Plateau,and the north of the Huaihe *** of the Q index and the summer rainfall total during 1961–2010 in China both exhibited an increasing trend,implying larger temporal variability in rainfall *** is illustrated that the summer precipitation in general became more temporally concentrated with more intense rainfall events and wetter days.

关键词： precipitation temporal concentration Q index climate change

Role of epithelial-mesenchymal transition in gastric cancer initiation and progression

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World Journal of Gastroenterology 2014年第18期20卷 5403-5410页

作者： Zhao Peng Chen-Xiao wang er-Hu Fang Guo-Bin wang Qiang Tong Department of Gastrointestinal Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and Technology

Gastric cancer is one of the most common malignant tumors *** to its intricate initiation and progression mechanisms,early detection and effective treatment of gastric cancer are difficult to *** epithelial-mesenchymal transition(EMT)is characterized as a fundamental process that is critical for embryonic development,wound healing and fibrotic *** evidence has established that aberrant EMT activation in the human stomach is closely associated with gastric carcinogenesis and tumor *** activation endows gastric epithelial cells with increased characteristics of mesenchymal cells and reduces their epithelial ***,mesenchymal cells tend to dedifferentiate and acquire stem cell or tumorigenic phenotypes such as invasion,metastasis and apoptosis resistance as well as drug resistance during EMT *** are a number of molecules that indicate the stage of EMT(e.g.,E-cadherin,an epithelial cell biomarker);therefore,certain transcriptional proteins,especially E-cadherin transcriptional repressors,may participate in the regulation of *** addition,EMT regulation may be associated with certain epigenetic *** aforementioned molecules can be used as early diagnostic markers for gastric cancer,and EMT regulation can provide potential targets for gastric cancer ***,we review the role of these aspects of EMT in gastric cancer initiation and development.

关键词： Epithelial-mesenchymal transition Gastric cancer Tumorigenesis Tumor progression Cancer stem cells

Chemical and chemoenzymatic stereoselectivesynthesis of β-nucleosides and their analogues

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Organic Chemistry Frontiers 2022年第6期9卷 1719-1741页

作者： Hui-jing wang Yang-Yang Zhong You-Cai Xiao Fen-er Chen Sichuan Research Center for Drug Precision Industrial Technology West China School of PharmacySichuan UniversityChengdu610041China Engineering Center of Catalysis and Synthesis for Chiral Molecules Department of ChemistryFudan UniversityShanghai200433China Shanghai Engineering Center of Industrial Asymmetric Catalysis for Chiral Drugs Shanghai 200433ChinaShanghai200433China

β-Nucleosides are fundamental building blocks of biological systems and are widely used as therapeuticagents for the treatment of cancer and viral infections, among others. In the last two years, nucleosideanalogues have been investigated with renewed urgency in the search for agents that are effective againstSARS-CoV-2, the cause of the ongoing global pandemic of COVID-19. This has resulted in an explosionof activities in the field of β-nucleoside synthesis. This review summarizes the historical perspective andthe recent advances in the stereoselective synthesis of β-nucleosides and their analogues. The syntheticstrategies to obtain β-nucleosides can be divided into three categories: (1) N-glycosylation;(2) intramolecular sugar ring formation;and (3) enzymatic transglycosylation.

关键词： synthesis analogues nucleoside

Picomolar inhibitor of reverse transcriptase featuring significantly improved metabolic stability

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Acta Pharmaceutica Sinica B 2023年第7期13卷 3054-3066页

作者： Ya-Li Sang Christophe Pannecouque erik De Clercq Shuai wang Fen-er Chen Department of Chemistry Engineering Center of Catalysis and Synthesis for Chiral MoleculesFudan UniversityShanghai 200433China Shanghai Engineering Center of Industrial Asymmetric Catalysis for Chiral Drugs Shanghai 200433China School of Science Harbin Institute of Technology(Shenzhen)Shenzhen 518055China Rega Institute for Medical Research KU LeuvenLeuven B-3000Belgium

Considering the undesirable metabolic stability of our recently identified NNRTI 5(t1/2=96 min)in human liver microsomes,we directed our efforts to improve its metabolic stability by introducing a new favorable hydroxymethyl side chain to the C-5 position of *** strategy provided a series of novel methylol-biphenyl-diarylpyrimidines with excellent anti-HIV-1 *** best compound 9g was endowed with remarkably improved metabolic stability in human liver microsomes(t1/2=2754 min),which was about 29-fold longer than that of 5(t1/2=96 min).This compound conferred picomolar inhibition of WT HIV-1(EC50=0.9 nmol/L)and low nanomolar activity against five clinically drug-resistant mutant *** maintained particularly low cytotoxicity(CC50=264μmol/L)and good selectivity(SI=256,438).Molecular docking studies revealed that compound 9g exhibited a more stable conformation than 5 due to the newly constructed hydrogen bond of the hydroxymethyl group with ***,compound 9g was characterized by good safety *** displayed no apparent inhibition of CYP enzymes and h *** acute toxicity assay did not cause death and pathological damage in mice at a single dose of 2 g/*** findings paved the way for the discovery and development of new-generation anti-HIV-1 drugs.

关键词： NNRTI HIV-1 DAPYs Picomolar Metabolic stability

Simulation and experimental research on extra-squeeze forming method during gradient sand molding

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China Foundry 2022年第4期19卷 288-298页

作者： er-biao Jiang Zhong-de Shan Guang Cheng Shao-zong wang Zhao-xian Gu Xin-lei wang State Key Laboratory of Advanced Forming Technology and Equipment China Academy of Machinery Science and Technology Group Co.Ltd.Beijing 100044China Nanjing University of Aeronautics and Astronautics Nanjing 210016China Beijing Union University Beijing 100101China

The flexible extrusion forming process (FEFP) is a sand mold patternless manufacturing technology that enables digital near-net shaping of complex sand molds. But, it is difficult to achieve the gradient sand molds with high surface strength and strong interior permeability by FEFP. To solve this problem, an extra-squeeze forming method based on FEFP for gradient sand mold was developed. To further reveal the extra-squeeze forming mechanism, based on the Johnson-Kendall-Roberts (JKR) theory and “gluing” notions, the single and double-sided squeeze models of gradient sand molds were established using the EDEM software. The squeezing processes of sand molds with different cavity depths of 60, 100, 140, 180, and 220 mm were systemically studied under single and double-sided squeeze conditions. The variation in the void fraction of sand mold as also investigated at a variety of extra-squeeze distances of 2, 3, 4, 5, and 6 mm, respectively. Simulation and test results show that a deeper cavity depth weakens the extrusion force transmission, which leads to a decrease in strength. The sand mold permeability and void fraction are identified to be positively correlated, while the tensile strength and void fraction appear to be negatively correlated. The void fraction of sand molds decreases with a longer extra-squeeze distance. A 6 mm extra-squeeze distance for the sand mold with 220 mm cavity depth results in a 26.8% increase in tensile strength with only a 5.7% reduction in the permeability. Hence, the extra- squeeze forming method can improve the quality of the sand mold by producing a gradient sand mold with high surface strength and strong interior permeability.

关键词： patternless casting gradient squeeze sand mold performance discrete element simulation void fraction

Structure-directed expansion of biphenyl-pyridone derivatives as potent non-nucleoside reverse transcriptase inhibitors with significantly improved potency and safety

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Chinese Chemical Letters 2023年第12期34卷 126-131页

作者： Li-Min Zhao Christophe Pannecouque erik De Clercq Shuai wang Fen-er Chen Engineering Center of Catalysis and Synthesis for Chiral Molecules Department of ChemistryFudan UniversityShanghai 200433China Shanghai Engineering Center of Industrial Asymmetric Catalysis for Chiral Drugs Shanghai 200433China Key Laboratory of Natural Resources of Changbai Mountain&Functional Molecules Ministry of EducationYanbian University College of PharmacyYanbian UniversityYanji 133002China Rega Institute for Medical Research KU LeuvenHerestraat 49Leuven B-3000Belgium

Following our previous work on human immunodeficiency virus-1(HIV-1)non-nucleoside reverse transcriptase inhibitors(NNRTIs),a series of novel biphenyl-pyridone derivatives were synthesized and evaluated for their anti-HiV-1 activity to expand their structure-activity *** of them exhibited low nanomolar activity toward wild-type HiV-1 and clinically relevant single/double mutant *** most active compound B1 was 231-fold more potent(EC_(50)=17nmol/L)than the lead compound 2(EC_(50)=3.93μmol/L)against wild-type(WT)*** compound was approximately 3.5-fold less cytotoxic(CC_(50)=100.58μmol/L)than compound 2(CC_(50)=28.24μmol/L),presenting a higher selectivity index(SI)value of *** with 2,the antiviral potency of B1 was significantly increased against five single mutant strains(L1001,K103N,E138K,Y181C and Y188L)and two double mutant strains(F227L+V106A and K103N+Y181C).Especially,K103N,Y181C and K103N+Y181C were more sensitive to B1 than both 2 and ***,the enzymatic inhibitory activity of B1 against wild-type HIV-1 reverse transcriptase was approximately 32-fold higher(IC_(50)=100nmol/L)than 2(IC_(50)=3.21μmol/L).Molecular docking studies and dynamic simulations were conducted to explain their potent *** together,this research represents an important step toward the discovery of novel biphenylpyridone drug candidates for HIV therapy.

关键词： HIV-1 NNRTI Doravirine Biphenyl-pyridone Safety

Neutralizing Antibody Responses against Five SARS-CoV-2 Variants and T Lymphocyte Change after Vaccine Breakthrough Infections from the SARS-CoV-2 Omicron BA.1 Variant in Tianjin, China: A Prospective Study

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Biomedical and Environmental Sciences 2023年第7期36卷 614-624页

作者： ZHANG Ying QU Jiang Wen ZHENG Min Na DING Ya Xing CHEN Wei YE Shao Dong LI Xiao Yan LI Yan Kun LIU Ying ZHU Di jin Can Rui wang LIN YANG jin Ye ZHAI Yu wang er Qiang MENG Xing Tianjin Center for Disease Control and Prevention Tianjin 300011China Tianjin Key Laboratory of Pathogenic Microbiology of Infectious Disease Tianjin 300011China National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China Sinovac Biotech Ltd Beijing 100085China

Objective To investigate whether Omicron BA.1 breakthrough infection after receiving the SARS-CoV-2 vaccine could create a strong immunity *** Blood samples were collected at two different time points from 124 Omicron BA.1 breakthrough infected patients and 124 controls matched for age,gender,and vaccination *** virus-neutralizing antibodies against five SARS-CoV-2 variants,including WT,Gamma,Beta,Delta,and Omicron BA.1,and T-lymphocyte lymphocyte counts in both groups were measured and statistically *** The neutralizing antibody titers against five different variants of SARS-CoV-2 were significantly increased in the vaccinated population infected with the Omicron BA.1 variant at 3 months after infection,but mainly increased the antibody level against the WT strain,and the antibody against the Omicron strain was the *** neutralizing antibody level decreased rapidly 6 months after *** T-lymphocyte cell counts of patients with mild and moderate disease recovered at 3 months and completely returned to the normal state at 6 *** Omicron BA.1 breakthrough infection mainly evoked humoral immune memory in the original strain after vaccination and hardly produced neutralizing antibodies specific to Omicron *** antibodies against the different strains declined rapidly and showed features similar to those of ***,T-lymphocytes may play an important role in recovery.

关键词： SARS-CoV-2 COVID-19 Omicron BA.1 T cells Neutralizing antibodies

Antidepressants combined with psychodrama improve the coping style and cognitive control network in patients with childhood trauma-associated major depressive disorder

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World Journal of Psychiatry 2022年第8期12卷 1016-1030页

作者： Ren-Qiang Yu Huan Tan er-Dong wang Jie Huang Pei-Jia wang Xiao-Mei Li Han-Han Zheng Fa-jin Lv Hua Hu Department of Radiology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China College of Art Soochow UniversitySuzhou 215006Jiangsu ProvinceChina Department of Psychiatry The First Affiliated Hospital of Chongqing Medical UniversityChongqing 40016China

BACKGROUND The use of antidepressant therapy alone has a limited efficacy in patients with childhood trauma-associated major depressive disorder(MDD).However,the effectiveness of antidepressant treatment combined with psychodrama in these patients is *** To evaluate the effectiveness of antidepressant treatment combined with *** Patients with childhood trauma-associated MDD treated with antidepressants were randomly assigned to either the psychodrama intervention(observation group)or the general health education intervention(control group)and received combination treatment for 6 *** observation group received general health education given by the investigator together with the“semi-structured group intervention model”of Yi Shu psychodrama.A total of 46 patients were recruited,including 29 cases in the observation group and 17 cases in the control *** of depression and anxiety as well as coping style and resting-state functional magnetic resonance imaging were assessed before and after the *** Symptoms of depression and anxiety,measured by the Hamilton Depression Scale,Beck Depression Inventory,and Beck Anxiety Inventory,were reduced after the intervention in both groups of *** coping style of the observation group improved significantly in contrast to the control group,which did *** addition,an interaction between treatment and time in the right superior parietal gyrus node was ***,functional connectivity between the right superior parietal gyrus and left inferior frontal gyrus in the observation group increased after the intervention,while in the control group the connectivity *** This study supports the use of combined treatment with antidepressants and psychodrama to improve the coping style of patients with childhood trauma-associated *** connectivity between the superior parietal gyrus and inferior frontal gyrus was increased after this combined treatmen

关键词： Major depressive disorder Childhood trauma Yi Shu psychodrama Cognitive control network Coping style