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Significance of platelet activating factor receptor expression in pancreatic tissues of rats with severe acute pancreatitis and effects of BN52021

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World Journal of Gastroenterology 2007年第21期13卷 2992-2998页

作者： Shi-Hai xia Chun-Xiu Hu Zhi-Ling zhao Guo-dong xia Yao Di Department of Gastroenterology Pancreas Center of Affiliated Hospital of Medical College of the Chinese People's Armed Police Forces Tianjin 300162 China

AIM:To investigate the dynamic changes and significance of platelet activating factor receptor (PAF-R) mRNA and protein in pancreatic tissues of rats with severe acute pancreatitis (SAP) and effects of BN52021 (Ginkgolide B). METHODS:Wistar male rats were randomly assigned to the negative control group (NC group),SAP model group (SAP group),and BN52051-remedy group (BN group),and each of the groups was divided into 6 subgroups at different time points after operation (1 h,2 h,3 h,6 h,12 h,and 24 h) (n=10 in each). PT-PCR and Western blot methods were used to detect PAF-RmRNA and protein expression in pancreatic tissues of rats respectively. Pathological examination of pancreatic tissues was performed and the serum amylase change was detected. RESULTS:Serum amylase and pathological results showed the that SAP model was successfully prepared,BN52021 was able to decrease serum amylase,and the pathological ratings in BN group at 3 h,6 h,and 12 h significantly decreased compared with those in the SAP group (8.85 ± 0.39 vs 5.95 ± 0.19,9.15 ± 0.55 vs 5.55 ± 0.36,10.10 ± 0.65 vs 6.72 ± 0.30,P < 0.05). The result of PAF-mRNA showed dynamic changes in SAP and BN groups,which increased gradually in early stage,reached a peak at 3 h (0.71 ± 0.14 vs 0.54 ± 0.14,0.69 ± 0.13 vs 0.59 ± 0.04,P < 0.05),and decreased gradually later. There were significant differences at each time point except 1 h and 2 h,when compared with those in the NC group (0.71 ± 0.14 or 0.69 ± 0.13 vs 0.47 ± 0.10,0.38 ± 0.08 or 0.59 ± 0.04 vs 0.47 ± 0.09,0.25 ± 0.07 or 0.29 ± 0.05 vs 0.46 ± 0.10,0.20 ± 0.06 or 0.20± 0.04 vs 0.43 ± 0.09,P < 0.05),whereas there was no significant difference between BN and SAP groups at each time point. The result of PAF-R protein showed that the change of PAF-R protein in the SAP group and the BN group was consistent with that of PAF-R mRNA. There were significant differences at each time point except 1 h,when compared with those in the NC group (0.90 ± 0.02 or 0.80 ± 0.05 vs 0.

关键词： Acute pancreatitis Platelet activating factor receptor BN52021

Plugging property and displacement characters of a novel high-temperature resistant polymer nanoparticle

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Petroleum Science 2022年第1期19卷 387-396页

作者： Zhi-Yong Wang Mei-Qin Lin Huai-Ke Li zhao-xia dong Juan Zhang Zi-Hao Yang Unconventional Petroleum Research Institute China University of Petroleum(Beijing)Beijing102249People's Republic of China Oilfield Chemicals R&D Institute China Oilfield Services LimitedLangfang065201People's Republic of China China University of Geosciences(Beijing) Beijing100083People's Republic of China

The goal of the research was to investigate the profile control and oil displacement characteristics of the polymer nanoparticles after high temperature *** displacement parameters showed considerable influence on the plugging effect of the high-temperature swelled polymer nanoparticles,such as the core permeability,concentration of nanoparticles in the suspension,swelling time and swelling temperature,which makes it flexible to control the plugging effect by controlling displacement experiments *** results show that polymer nanoparticles dispersion system with a concentration of 500 mg/L is suitable for cores plugging with a permeability of 30×10^(-3)-150×10^(-3)μm^(2),even after aging at 150℃ for three *** shunt flow experiments show that when the displacement factors are optimal values,the polymer nanoparticles after high temperature swelling to plug the high-permeability layer selectivity and almost do not clog the low-permeability *** recovery of homogeneous artificial core displacement experiment and a heterogeneous double-tube cores model are increased by 20%and 10.4%on the basis of water *** polymer nanoparticles can be a great help for petroleum engineers to better apply this deep profile control and flooding technology.

关键词： Polymer nanoparticles High temperature resistance Plugging property EOR

Influence of dissolved oxygen content on oxidative stability of linked polymer solution

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Petroleum Science 2009年第4期6卷 421-425页

作者： zhao-xia dong Mei-qin Lin Jian Xin Ming-yuan Li China Univ Petr Enhanced Oil Recovery Res Ctr Beijing 102249 Peoples R China

The influence of dissolved oxygen content on the oxidative stability of a linked polymer solution (LPS) was studied by micro-filtration, dynamic light scattering and viscosity measurements. The results showed that at the same temperature, the degree of the oxidative degradation of the LPS increased and the rapidity of the oxidative degradation was accelerated with the increase of the dissolved oxygen content. Consequently, the size of linked polymer coils (LPCs) of the LPS became small, and the plugging capability of the LPS decreased. At a fixed content of dissolved oxygen, with increasing degradation temperature, almost the same results were observed, namely, an increased degree of oxidative degradation, accelerated rapidity of the oxidative degradation and decreased plugging capacity, with decreased oxidative stability of LPS. At 90 °C, in the presence of oxygen, LPS lost its plugging capability after having been degraded for a period of time. But at 40 °C, LPS with low dissolved oxygen content could be stable for a long time. The decreased plugging ability of LPS after oxidative degradation is mainly caused by the decreased size and number of the LPCs due to the breaking of hydrolyzed polyacrylamide (HPAM) molecule segments and the structural changing of HPAM molecules.

关键词： Linked polymer solution HPAM content of dissolved oxygen degradation stability

The hazardous effects of tobacco smoking on male ertility

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Asian Journal of Andrology 2015年第6期17卷 954-960,I0009页

作者： Jing-Bo Dai zhao-xia Wang Zhong-dong Qiao School of Life Sciences and Biotechnology Shanghai Key Laboratory of Reproductive Medicine Shanghai Jiao Tong University Shanghai 200240 China

The substantial harmful effects of tobacco smoking on fertility and reproduction have become apparent but are not generally appreciated. Tobacco smoke contains more than 4000 kinds of constituents, including nicotine, tar, carbonic monoxide, polycyclic aromatic hydrocarbons, and heavy metals. Because of the complexity of tobacco smoke components, the toxicological mechanism is notably complicated. Most studies have reported reduced semen quality, reproductive hormone system dysfunction and impaired spermatogenesis, sperm maturation, and spermatozoa function in smokers compared with nonsmokers. Underlying these effects, elevated oxidative stress, DNA damage, and cell apoptosis may play important roles collaboratively in the overall effect of tobacco smoking on male fertility. In this review, we strive to focus on both the phenotype of and the molecular mechanism underlying these harmful effects, although current studies regarding the mechanism remain insufficient.

关键词： DNA fragmentation heavy metals nicotine oxidative stress semen quality spermatogenesis

2D Janus polymer nanosheets for enhancing oil recovery:From material ppreparation to property evaluation

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Petroleum Science 2023年第3期20卷 1584-1597页

作者： Hao Shen Zi-Hao Yang Guan-Zhong Wang Yi-Lin Xiong Qi-Chao Lv Qi Cao Qi-Qi Niu Yi-Bo Wang zhao-xia dong Unconventional Petroleum Research Institute China University of Petroleum(Beijing)Bejing102249China Sinopec Zhenhai Refining and Chemical Company Ningbo315207ZhejiangChina Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen518055GuangdongChina School of Energy Resources China University of Geosciences(Bejing)Bejing100083China

Janus amphiphilic polymer nanosheets(JAPNs)with anisotropic morphology and distinctive perfor-mance have aroused widespread ***,due to the difficulty in synthesis and poor dispersion stability,JAPNs have been scarcely reported in the field of enhancing oil recovery(EOR).Herein,a kind of organic-based flexible JAPNs was prepared by paraffin emulsion *** lateral sizes of JAPNs were ranging from hundreds of nanometers to several micrometers and the thickness was about 3 *** organic-based nanosheets were equipped with remarkably flexible structures,which could improve their injection *** dispersion and interfacial properties of JAPNs were studied *** modification of crosslinking agent containing multiple amino groups,the JAPNs had excellent hydro-philicity and salt resistance compared with conventional inorganic or composite *** settling time of nanosuspension with NaCl and CaCl_(2) at a low salinity of 1000 mg/L was over 240 *** value could also remain 124 h under the salinity of 10,000 mg/L *** the dual functionalities of Janus amphiphilic nature and nanoparticles'Pickering effect,JAPNs could change rock wettability and form emulsions as"colloidal surfactants",In particular,a new technology called optical microrheology was pioneered to explore the destabilization state of nanosuspensions for the first *** precipitation lagged behind aggregation,especially for stable suspension systems,the onset of the unstable behavior was difficult to be detected by conventional methods,which should be the indicator of reduced effec-tiveness for nanofluid *** addition,the oil displacement experiments demonstrated that the JAPNs could enhance oil recovery by 17.14%under an ultra-low concentration of 0.005%and were more suitable for low permeability *** findings can help for a better understanding of the material preparation of polymer *** also hope that this study could shed more light

关键词： 2D materials Polymer nanosheets Enhance oil recovery Janus nature Amphiphilic property

正丙醇水溶液准弹性中子散射光谱的分子动力学模拟

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物理化学学报 2012年第5期28卷 1037-1044页

作者：张霞张强赵东霞渤海大学化学化工与食品安全学院辽宁锦州121000 辽宁师范大学化学化工学院辽宁大连116029

准弹性中子散射(QENS)光谱是获取溶液分子动力学性质的重要方法,但光谱解析模型的有效性和去耦合近似的合理性仍存在争议.本文利用分子动力学模拟方法获取纯水和正丙醇水溶液中羟基氢原子的自相关中间散射函数FS(Q,t)和去耦合近似函数FP... 详细信息

准弹性中子散射(QENS)光谱是获取溶液分子动力学性质的重要方法,但光谱解析模型的有效性和去耦合近似的合理性仍存在争议.本文利用分子动力学模拟方法获取纯水和正丙醇水溶液中羟基氢原子的自相关中间散射函数FS(Q,t)和去耦合近似函数FP(Q,t),以及相关性质来评价它们的合理性.结果表明,在低动量转移范围内平-转去耦合近似相对合理,水分子的平-转耦合贡献较小,混合溶液中水分子的平-转耦合项和转动项随动量转移Q值增大而增大,二者显现相互抵消趋势.对于混合溶液中的正丙醇羟基氢原子,由于FS(Q,t)和质心自相关中间散射函数FCM(Q,t)偏差较大,利用实验光谱直接拟合分子平动扩散系数是不合适的.三种平动模型获取的纯水和正丙醇水溶液分子平动扩散系数与实验结果一致,略高于Einstein均方位移方法所得结果.水分子在纯水和混合溶液中表现为跳跃转动,而不是连续转动.正丙醇分子存在转动各向异性,羟基氢原子沿羟基向量为跳跃转动,沿相对质心向量可近似为连续转动.模拟结果显示,高动量转移范围平-转耦合项贡献较大,直接拟合实验光谱获取分子转动扩散系数或弛豫时间是不合适的.鉴于低动量转移范围内转动和平转耦合贡献较小,以及二者的抵消作用,在此范围内获取水分子平动信息是现实可行的.

关键词：准弹性中子散射光谱分子动力学模拟非相干结构因子自相关中间散射函数跳跃扩散

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水溶液中氢键寿命的定义和弛豫机理(英文)

物理化学学报 2011年第11期27卷 2547-2552页

作者：张霞张强赵东霞渤海大学化学化工与食品安全学院辽宁锦州121000 辽宁师范大学化学化工学院辽宁大连116029

氢键弛豫过程决定水溶液中分子的动力学行为,氢键寿命作为理论和实验结果中一个重要的参数通常用以描述溶液中的氢键动力学性质.本文采用SPC/E-P2和SPC/E-OPLS两种力场方法对二甲基亚砜(DMSO)水溶液体系进行分子动力学模拟,计算了四种... 详细信息

氢键弛豫过程决定水溶液中分子的动力学行为,氢键寿命作为理论和实验结果中一个重要的参数通常用以描述溶液中的氢键动力学性质.本文采用SPC/E-P2和SPC/E-OPLS两种力场方法对二甲基亚砜(DMSO)水溶液体系进行分子动力学模拟,计算了四种不同定义下的氢键寿命,并进行了对比阐述.连续性氢键寿命T_C和基于动力学平衡方法下的氢键寿命T_R较短,它们忽略了不成功的氢键交换过程,稳定态模型下的氢键寿命T_(PR)能够真实体现氢键转换过程,可作为标度衡量其它量值.间歇性氢键寿命T_I相对最长,重复统计了氢键成功交换后的恢复概率.随着二甲基亚砜浓度增大,T_C、T_I、T_R和T_(PR)不断增大,分子平动扩散系数在中等浓度达到极小,说明氢键寿命与分子活动性无决定性关联,同类型氢键在不同浓度下的寿命差异表明氢键寿命具有分子环境依赖性;水分子和二甲基亚砜分子氢键个数降低,氢键受激角度扭曲和拉伸概率下降,T_C和T_R不断接近,氢键交换受体密度降低使氢键交换速率下降,T_(PR)断增大,氢键寿命与其周围氢键密度密切相关.T_1与T_(PR)的比值体现了氢键交换的局域性,其变化趋势与分子平动活动性趋势相同.两种力场下氢键寿命的差异也说明氢键的寿命具有明显的理论模型依赖性.

关键词：氢键寿命分子动力学模拟氢键交换相关函数分子力场

微过氧化物酶水溶液的ABEEM/MM动力学模拟

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物理化学学报 2008年第6期24卷 1035-1040页

作者：崔宝秋宫利东赵东霞辽宁师范大学化学化工学院

应用原子-键电负性均衡浮动电荷分子力场(ABEEM/MM),对微过氧化物酶水溶液进行了分子动力学模拟.研究了水溶液对微过氧化物酶的结构,血红素的皱裂构象以及轴配体咪唑基的取向的影响.结果表明,在水溶液中微过氧化物酶的骨架氨基酸是稳定... 详细信息

应用原子-键电负性均衡浮动电荷分子力场(ABEEM/MM),对微过氧化物酶水溶液进行了分子动力学模拟.研究了水溶液对微过氧化物酶的结构,血红素的皱裂构象以及轴配体咪唑基的取向的影响.结果表明,在水溶液中微过氧化物酶的骨架氨基酸是稳定的,而血红素的皱裂构象在水分子的作用下趋于平面.与血红素轴配体咪唑基键连的组氨酸决定着咪唑基的空间取向,而咪唑基与血红素侧链的丙酸基的静电作用对其取向仅起次要作用.

关键词： ABEEM/MM浮动电荷分子力场微过氧化物酶血红素构象分子动力学模拟

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铵根离子在水溶液中的跳跃转动机理（英文）

物理化学学报 2015年第8期31卷 1461-1467页

作者：张强程程张霞赵东霞渤海大学化学系辽宁锦州121000 辽宁师范大学化学系辽宁大连116029

铵根离子的动力学行为与生命体内的生物和化学过程密切相关.依据流体力学理论,由于铵根离子与水分子之间存在多个强氢键,其转动应较慢,但实验结果并非如此,其转动的微观机理尚不清晰.本文分子动力学模拟研究表明,水溶液中铵根离子主要... 详细信息

铵根离子的动力学行为与生命体内的生物和化学过程密切相关.依据流体力学理论,由于铵根离子与水分子之间存在多个强氢键,其转动应较慢,但实验结果并非如此,其转动的微观机理尚不清晰.本文分子动力学模拟研究表明,水溶液中铵根离子主要以快速、大角度的跳跃方式进行转动,像水分子一样遵从扩展分子跳跃转动模型.通过微观转动模式的分解和两种转动弛豫时间的比较发现,相对其氢键骨架的扩散转动,跳跃转动对其转动速率贡献更大,并随浓度增大不断强化.与水分子氢键交换方式相比,铵根离子更倾向于在非氢键相连的水分子间发生交换.

关键词：铵根离子跳跃转动氢键分子动力学模拟扩展跳跃模型