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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

Study of deep transportation and plugging performance of deformable gel particles in porous media

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Petroleum Science 2024年第2期21卷 962-973页

作者： Wen-jing Zhao jing wang Zhong-Yang Qi hui-Qing Liu National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China

Deformable gel particles(DGPs) possess the capability of deep profile control and flooding. However, the deep migration behavior and plugging mechanism along their path remain unclear. Breakage, an inevitable phenomenon during particle migration, significantly impacts the deep plugging effect. Due to the complexity of the process, few studies have been conducted on this subject. In this paper, we conducted DGP flow experiments using a physical model of a multi-point sandpack under various injection rates and particle sizes. Particle size and concentration tests were performed at each measurement point to investigate the transportation behavior of particles in the deep part of the reservoir. The residual resistance coefficient and concentration changes along the porous media were combined to analyze the plugging performance of DGPs. Furthermore, the particle breakage along their path was revealed by analyzing the changes in particle size along the way. A mathematical model of breakage and concentration changes along the path was established. The results showed that the passage after breakage is a significant migration behavior of particles in porous media. The particles were reduced to less than half of their initial size at the front of the porous media. Breakage is an essential reason for the continuous decreases in particle concentration, size, and residual resistance coefficient. However, the particles can remain in porous media after breakage and play a significant role in deep plugging. Higher injection rates or larger particle sizes resulted in faster breakage along the injection direction, higher degrees of breakage, and faster decreases in residual resistance coefficient along the path. These conditions also led to a weaker deep plugging ability. Smaller particles were more evenly retained along the path, but more particles flowed out of the porous media, resulting in a poor deep plugging effect. The particle size is a function of particle size before inject

关键词： Physical simulation Deformable gel particle Breakage Particle size Residual resistance coefficient

Development of CONTHAC-3D and hydrogen distribution analysis of HPR1000

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Nuclear Science and Techniques 2024年第2期35卷 210-221页

作者： hui wang jing-jing Li Yuan Chang Gong-Lin Li Ming Ding China Nuclear Power Engineering Co.LTD. Beijing 100084China Fundamental Science on Nuclear Safety and Simulation Technology Laboratory Harbin 100049China

An in-house code,CONTHAC-3D,was developed to calculate and analyze thermal-hydraulic phenomena in containments during severe ***-3D is a three-dimensional computational fluid dynamics code that can be applied to predict gas flow,diffusion,and steam condensation in a containment during a severe hypothetical accident,as well as to obtain an estimate of the local hydrogen concentration in various zones of the ***-3D was developed using multiple models to simulate the features of the proprietary systems and equipment of HPR1000 and ACP100,such as the passive cooling system,passive autocatalytic recombiners and the passive air cooling *** validate CONTHAC-3D,a GX6 test was performed at the Battelle Model Containment *** hydrogen concentration and temperature monitored by the GX6 test are accurately predicted by ***,the hydrogen distribution in the HPR1000 containment during a severe accident was *** results show that the hydrogen removal rates calculated using CONTHAC-3D for different types of PARs agree well with the theoretical values,with an error of less than 1%.As the accident progresses,the hydrogen concentration in the lower compartment becomes higher than that in the large space,which implies that the lower compartment has a higher hydrogen risk than the dome and large space at a later stage of the *** amount of hydrogen removed by the PARs placed on the floor of the compartment is small;therefore,raising the installation height of these recombiners appropriately is ***,we do not recommend installing all autocatalytic recombiners at high *** study findings in regard to the hydrogen distribution in the HPR1000 containment indicate that CONTHAC-3D can be applied to the study of hydrogen risk containment.

关键词： Hydrogen risk mitigation Pressurized water reactor HPR1000 Thermal hydraulic CONTHAC-3D

Ocular development in children with unilateral congenital cataract and persistent fetal vasculature

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International Journal of Ophthalmology(English edition) 2022年第3期15卷 426-431页

作者： Shu-Yi Zhang hui Chen jing-hui wang Wan Chen Qi-Wei wang jing-jing Chen Xiao-Shan Lin Zhuo-Ling Lin Duo-Ru Lin Hao-Tian Lin Wei-Rong Chen State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangzhou 510060Guangdong ProvinceChina Center for Precision Medicine Sun Yat-sen UniversityGuangzhou 510060Guangdong ProvinceChina

AIM: To investigate the ocular development of patients who had unilateral congenital cataract(CC) combined with persistent fetal vasculature(PFV).METHODS: This cross-sectional, observational study included patients who had unilateral CC and PFV and those with isolated unilateral *** length(AL), keratometry, anterior chamber depth(ACD), lens thickness, and vitreous length were *** ocular biometric parameters of the affected eyes of patients with CC and PFV were compared with the fellow eyes and with the affected eyes of patients with isolated ***: A total of 110 patients were included and divided into 4 groups: group 1(18 patients with CC and PFV, 0.05).CONCLUSION: Compared with the fellow eyes, the ALs of the eyes with unilateral CC and PFV are shorter in patients younger than 24 mo and longer in those older than 24 mo;the keratometries of the eyes with unilateral CC and PFV are steeper in patients older than 24 mo and similar with those younger than 24 *** findings provide further understanding of ocular development in patients with both CC and PFV.

关键词： ocular development congenital cataract persistent fetal vasculature axial length keratometry

Influence of ash composition on the sintering behavior during pressurized combustion and gasification process

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第3期13卷 230-238页

作者： Ni-jie jing Qin-hui wang Yu-kun YANG Le-ming CHENG Zhong-yang LUO Ke-fa CEN State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

To determine the ash characteristics during fluidized bed combustion and gasification purposes, the investigation of the impacts of chemical composition of Jincheng coal ash on the sintering temperature was conducted. A series of experiments on the sintering behavior at 0.5 MPa was performed using the pressurized pressure-drop technique in the combustion and gasification atmospheres. Meanwhile, the mineral transformations of sintered ash pellets were observed using X-ray diffractometer （XRD） analyzer to better understand the experimental results. In addition, quantitative XRD and field emission scanning electron microscope/energy dispersive X-ray spectrometer （FE-SEM/EDS） analyses of ash samples were used for clarifying the detailed ash melting mechanism. These results show that the addition of Fe203 can obviously reduce the sintering temperatures under gasification atmospheres, and only affect a little the sintering temperature under combustion atmosphere. This may be due to the presence of iron-bearing minerals, which will react with other ash compositions to produce low-melting-point eutectics. The FE-SEM/EDS analyses of ash samples with Fe203 additive show consistent results with the XRD measurements. The CaO and Na20 can reduce the sintering temperatures under both the combustion and gasification atmospheres. This can be also contributed to the formation of low-melting-point eutectics, decreasing the sintering temperature. Moreover, the fluxing minerals, such as magnetite, anhydrite, muscovite, albite and nepheline, contribute mostly to the reduction of the sintering temperature while the feldspar minerals, such as anorthite, gehlenite and sanidine, can react with other minerals to produce low-melting-point eutectics, and thereby reduce the sintering temperatures.

关键词： Ash composition Sintering temperature X-ray diffractometer (XRD) Field emission scanning electron microscope/energy dispersive X-ray spectrometer (FE-SEM/EDS)

Effects of acid-rock reaction on physical properties during CO_(2)-rich industrial waste gas(CO_(2)-rich IWG)injection in shale reservoirs

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Petroleum Science 2024年第1期21卷 272-285页

作者： Yi-Fan wang jing wang hui-Qing Liu Xiao-Cong Lv Ze-Min Ji National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China Research Institute of Exploration and Development PetroChinaBeijing100083China

"Carbon peaking and carbon neutrality"is an essential national strategy,and the geological storage and utilization of CO_(2)is a hot issue ***,due to the scarcity of pure CO_(2)gas sources in China and the high cost of CO_(2)capture,CO_(2)-rich industrial waste gas(CO_(2)-rich IWG)is gradually emerging into the public's ***_(2)has good adsorption properties on shale surfaces,but acidic gases can react with shale,so the mechanism of the CO_(2)-rich IWG-water-shale reaction and the change in reservoir properties will determine the stability of geological ***,based on the mineral composition of the Longmaxi Formation shale,this study constructs a thermodynamic equilibrium model of water-rock reactions and simulates the regularity of reactions between CO_(2)-rich IWG and shale *** results indicate that CO_(2)consumed 12%after reaction,and impurity gases in the CO_(2)-rich IWG can be dissolved entirely,thus demonstrating the feasibility of treating IWG through water-rock *** IWG inhibits the dissolution of CO_(2),the optimal composition of CO_(2)-rich IWG is 95%CO_(2)and 5%IWG when CO_(2)geological storage is the main *** contrast,when the main goal is the geological storage of total CO_(2)-rich IWG or impurity gas,the optimal CO_(2)-rich IWG composition is 50%CO_(2)and 50%*** the CO_(2)-rich IWG-water-shale reaction,temperature has less influence on the water-rock reaction,while pressure is the most important ***2 has the greatest impact on water-rock reaction in *** minerals,clay minerals such as illite and montmorillonite had a significant effect on water-rock *** overall reaction is dominated by precipitation and the volume of the rock skeleton has increased by 0.74 cm3,resulting in a decrease in shale porosity,which enhances the stability of CO_(2)geological storage to some *** the reaction between CO_(2)-rich IWG-water-shale at simulated temperatures and pressures,precipitation

关键词： CO_(2)-rich industrial waste gas Geological storage Acid-rock reaction Shale Geochemical modelling

Hypomethylation of glycine dehydrogenase promoter in peripheral blood mononuclear cells is a new diagnostic marker of hepatitis B virus-associated hepatocellular carcinoma

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 35-42页

作者： Li-Li Miao jing-Wen wang hui-hui Liu Shuai Gao Yu-Chen Fan Kai wang Department of Hepatology Qilu Hospital of Shandong UniversityJinan 250012China Experimental Center Shandong University of Traditional Chinese MedicineJinan 250355China Institute of Hepatology Shandong UniversityJinan 250012China

Background: Glycine dehydrogenase(GLDC) plays an important role in the initiation and proliferation of several human cancers. In this study, we aimed to detect the methylation status of GLDC promoter and its diagnostic value for hepatitis B virus-associated hepatocellular carcinoma(HBV-HCC). Methods: We enrolled 197 patients, 111 with HBV-HCC, 51 with chronic hepatitis B(CHB), and 35 healthy controls(HCs). The methylation status of GLDC promoter in peripheral mononuclear cells(PBMCs) was identified by methylation specific polymerase chain reaction(MSP). The mRNA expression was examined using real-time quantitative polymerase chain reaction(q PCR). Results: The methylation frequency of the GLDC promoter was significantly lower in HBV-HCC patients(27.0%) compared to that in CHB patients(68.6%) and HCs(74.3%)( P < 0.001). The methylated group had lower alanine aminotransferase level( P = 0.035) and lower rates of tumor node metastasis(TNM) Ⅲ/Ⅳ( P = 0.043) and T3/T4( P = 0.026). TNM stage was identified to be an independent factor for GLDC promoter methylation. GLDC mRNA levels in CHB patients and HCs were significantly lower than those in HBV-HCC patients( P = 0.022 and P < 0.001, respectively). GLDC mRNA levels were significantly higher in HBV-HCC patients with unmethylated GLDC promoters than those with methylated GLDC promoters( P = 0.003). The diagnostic accuracy of alpha-fetoprotein(AFP) combined with GLDC promoter methylation for HBV-HCC was improved compared with that of AFP alone(AUC: 0.782 vs. 0.630, P < 0.001). In addition, GLDC promoter methylation was an independent predictor for overall survival of HBV-HCC patients( P = 0.038). Conclusions: The methylation frequency of GLDC promoter was lower in PBMCs from HBV-HCC patients than that from patients with CHB and HCs. The combination of AFP and GLDC promoter hypomethylation significantly improved the diagnostic accuracy of HBV-HCC.

关键词： Hepatocellular carcinoma Glycine dehydrogenase DNA methylation Peripheral blood mononuclear cells

Progress in the research on organic piezoelectric catalysts for dye decomposition

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 245-260页

作者： Zhaoning Yang Xiaoxin Shu Di Guo jing wang hui Bian Yanmin Jia School of Science Xi’an University of Posts and TelecommunicationsXi’an 710121China School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710119China

Organic contaminants have posed a direct and substantial risk to human wellness and the *** recent years,piezo-electric catalysis has evolved as a novel and effective method for decomposing these *** piezoelectric materials offer a wide range of options,most related studies thus far have focused on inorganic materials and have paid little attention to organic *** materials have advantages,such as being lightweight,inexpensive,and easy to process,over inorganic ***,this paper provides a comprehensive review of the progress made in the research on piezoelectric catalysis using organic materials,high-lighting their catalytic efficiency in addressing various *** addition,the applications of organic materials in piezoelectric cata-lysis for water decomposition to produce hydrogen,disinfect bacteria,treat tumors,and reduce carbon dioxide are ***,fu-ture developmental trends regarding the piezoelectric catalytic potential of organic materials are explored.

关键词： piezoelectric catalysis piezoelectric material dye decomposition organic materials

Decreased expression of Neurensin-2 correlates with poor prognosis in hepatocellular carcinoma

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World Journal of Gastroenterology 2009年第38期15卷 4844-4848页

作者： Hai-Qing Ma Xiao-Ting Liang jing-jing Zhao hui wang Jian-Cong Sun Yi-Bing Chen Ke Pan Jian-Chuan Xia Key Laboratory of Oncology in Southern China and Departmentof Experimental Research Sun Yat-sen University Cancer CenterGuangzhou 510060 Guangdong Province China

AIM： To investigate the expression of Neurensin-2 （NRSN2） in hepatocellular carcinoma （HCC） and its prognostic values in predicting survival. METHODS： The expression and prognostic significance of NRSN2 in HCC was examined by performing immunohistochemical analysis using a total of 110 HCC clinical tissue samples, and Western blotting analysis to further confirm the result. RESULTS： Decreased NRSN2 expression was shown in 70.9% cases. Loss of NRSN2 expression in HCC was significantly related to tumor size （P = 0.006）. Larger tumor size was related to negative expression of NRSN2. Patients showing negative NRSN2 expression had a significantly shorter overall survival than those with positive expression （P = 0.008）. Multivariate Cox regression analysis indicated that NRSN2 expression level was an independent factor of survival （P = 0.013）. Western blotting analysis further confirmed decreased expression of NRSN2 in tumor tissues compared with non-tumorous tissues. CONCLUSION： Our study indicated that NRSIV2 could be a tumor suppressor gene for HCC and a candidate biomarker for long-term survival in HCC.

关键词： Neurensin-2 Hepatocellular carcinoma Expression Immunohistochemical analysis Prognosis