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Synthesis, Crystal Structure and Biological Activity of 2-Chloro-N-{2-fluoro-5-[N-(phenylsulfonyl) phenyl-sulfonamido]phenyl}benzamide

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Chemical Research in Chinese Universities 2008年第3期24卷 295-298页

作者： li wen-ming WANG jian-guo li Zheng-ming SONG Hai-bin Elemento-Organic Chemistry Institute State Key Laboratory of Elemento-Organic Chemistry National Pesticide Engineering Research Center Nankai University Tianjin 300071 P R. China

2-Chloro-N-{2-fluoro-5-[N-（phenylsulfonyl）phenylsulfonamido]phenyl}benzamide was synthesized and its crystal structure was also determined by X-ray single-crystal diffraction. The title compound（C25H18ClFN2O5S2） belongs to monoclinic, space group P21/n with a=0.7377（3） nm, b=1.2036（5） nm, c=2.6846（11） nm, β=90.895（9）°, V=2.3833（16） nm3, Mr=544.98, Z=4, Dc=1.519 g/cm3, μ=0.385 mm–1, F（000）=1120, R1=0.0632, and wR2=0.1438. Its crystal structure belongs to a novel class that has not been reported yet, and its preliminary herbicidal activity was also tested. Its inhibition rate to seedling growth of barnyard grass reaches 15.1% at 100 μg/mL.

关键词： X-ray diffraction Crystal structure Synthesis Biological activity

Magnetic Properties of a Mixed Spin-2 and Spin-5/2 Heisenberg Ferrimagnetic System on a Two-Dimensional Honeycomb Lattice： Green＇s Function Approach

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Communications in Theoretical Physics 2007年第4期47卷 741-746页

作者： YAO Kai-Lun li jian-wen liU Zu-li FU Hua-Hua ZU lin Department of Physics Huazhong University of Science and Technology Wuhan 430074 China International Center of Material Physics the Chinese Academy of Sciences Shenyang 110015 China

The multisublattice Green＇s function technique is applied to study the magnetic properties of a mixed spin-2 and spin-5/2 Heisenberg ferrimagnetic system on a two-dimensional honeycomb lattice. The role of the different interactions in the Hamiltonian is explored. When only the nearest-neighbor interaction and the single-ion anisotropy are included, our results indicate that there are compensation points at finite temperatures. When the next-nearest-neighbor interaction exceeds a minimum value that depends on the other parameters in the Hamiltonian, the compensation point disappears. The next-nearest-neighbor interaction has the effect of changing the compensation temperature.

关键词： Heisenberg ferrimagnetic Green function spin-wave spectra magnetization critical temperature compensation temperature

Evaluation of radiosensitivity of human tumor cells after irradiation of γ-rays based on G2-chromosome aberrations

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Nuclear Science and Techniques 2006年第5期17卷 268-271页

作者： WANG Zhuan-Zi li wen-jian YANG jian-She JIN Xiao-Dong WANG Ju-Fang GUO Chuan-ling Institute of Modern Physics the Chinese Academy of Sciences Lanzhou 730000 China Graduate School of Chinese Academy of Sciences Beijing 100049 China

The aim of the present investigation is to determine initial G2-chromosome aberrations and to validate whether the G2-chromosome aberrations can predict the cellular clonogenic survival in human tumor cell lines. Cell lines of human ovary carcinoma cells (HO8910) and human hepatoma cells (HepG2) were irradiated with a range of doses and assessed both for initial G2-chromosome aberrations and for cell survival after γ -irradiation. The initial G2-chromosome aberrations were measured by counting the number of G2-chromatid breaks after irradiation, detected by the premature chromosome condensation technique, and the G2-assay method. Cell survival was documented by a colony formation assay. A linear-quadratic survival curve was observed in both cell lines. The dose–response results show that the numbers of G2-chromatid breaks increase with the increase in dose in the two cell lines. At higher doses (higher than 4 Gy) of irradiation, the number of G2-chromatid breaks for the G2-assay method cannot be determined because too few cells reach mitosis, and hence their detection is difficult. A good correlation is found between the clonogenic survival and the radiation-induced initial G2-chromatid breaks per cell (r = 0.9616). The present results suggest that the premature chromosome condensation technique may be useful for determining chromatid breaks in G2 cells, and the number of initial G2-chromatid breaks holds promise for predicting the radiosensitivity of tumor cells.

关键词：染色体畸变 γ射线辐射未成熟染色体浓缩放射敏感度人肿瘤细胞群体形成化验

Trans Fatty Acid Levels in Foods and Intakes among Population Aged 3 Years and above in Beijing and Guangzhou Cities,China

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Biomedical and Environmental Sciences 2015年第7期28卷 477-485页

作者： liU Ai Dong li jian wen liU Zhao Ping ZHOU Ping Ping MAO Wei Feng li Ning ZHANG Lei Key Laboratory of Food Safety Risk Assessment Ministry of Health China National Center for Food Safety Risk Assessment

Objective To understand the dietary intake levels of trans fatty acids （TFA） in a Chinese population and establish a basis for health risk assessment of trans fatty acids. Methods The TFA contents data of 2613 food items and food consumption data of 10,533 people aged 3 years and above in two large cities in China were matched and a simple assessment method was used to estimate the distribution of dietary TFA intake. Results The mean content of TFA was highest in margarine （1.68±0.83 g/100g）, followed by chocolate and candy （0.89±2.68 g/100g）, edible vegetable oils （0.86±0.82 g/100g）, milk （0.83±1.56 g/100g）, and bakery foods （0.41±0.91 g/100g）. TFA intake accounted for 0.34%, 0.30%, 0.32%, and 0.29% of the total energy intake in the 3-6, 7-12, 13-17, and 〉18 year age groups, respectively. Of the populations studied, 0.42% demonstrated TFA intakes （as percentage of energy intake） greater than 1%. The main sources of dietary TFA intake were edible vegetable oils, milk, mutton, and beef, and baked foods, which accounted for 49.8%, 16.56%, 12.21%, and 8.87%, respectively. Conclusion The current intake of TFA among concern regarding the threshold of TFA intake people in two cities did not appear to be of major health as the percentage of total energy recommended by the World Health Organization. Because most TFA were derived from industrially processed foods, the government should reinforce nutrition labeling and regulate food producers to further reduce TFA in food and to provide scientific instruction for consumers to make sound choices.

关键词： Trans fatty acid Intake Food sources China

Bystander effects induced by medium from carbon-ion-irradiated human cancer cells

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Nuclear Science and Techniques 2005年第4期16卷 204-208页

作者： WANG Ju-Fang li wen-jian ZHOU Guang-Ming DANG Bing-Rong MA Qiu-Feng FENG Yan Institute of Modern Physics the Chinese Academy of Sciences Lanzhou 730000 Graduate School of the Chinese Academy of Sciences Beijing 100049

The bystander effects induced by medium from human hepatoma SMMC-7721 and adenocarcinoma F56 cells irradiated with carbon ions were investigated. It was found that the survival fraction (SF) of the irradiated cells decreased exponentially along with the increased dose. SMMC-7721 cells were more radiosensitive than F56 cells. The plating efficiency (PE) of the non-irradiated cells treated with irradiated conditioned medium (ICM) was obvi-ously lower than the PE of control cells for SMMC-7721 cells but not for F56 cells. Moreover, the reduced PE and SF by ICM treatment were more significant for 1Gy irradiation than for 6Gy irradiation on SMMC-7721 cells. These results suggest that the irradiated cells can secrete factor(s) into medium that is cytotoxic to bystander non-irradiated cells. The bystander effects are dependent on cell genotype presented at the time of irradiation and radiation dose. This makes impact on the precise estimation of the effects of radiation and tumor radiotherapy.

关键词：碳癌症细胞毒素基因放射物

Killing effect of Chinese hamster V79 cells exposed to accelerated carbon ions and RBE determination

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Nuclear Science and Techniques 2002年第4期13卷 259-263页

作者： li Qiang, ZHOU Guang-Ming, WANG Ju-Fang, li wen-jian, WEI Zeng-Quan(Institute of Modern Physics, the Chinese Academy of Sciences, Lanzhou 730000) Institute of Modern Physics the Chinese Academy of Sciences Lanzhou 730000

Survival curves of Chinese hamster V79 cells exposed to accclerated carbon ions with linear energy transfers of 125.5, 200 and 700 keV/μm were measured, respectively. Inactivation cross sections corresponding to the irradiation above were deduced from the V79 cell survival curves. They are 7.86±0.17, 10.44±1.11 and 32.32±3.58 μm2 in turn. With the surviving response of V79 cells to 60Co γ-rays as a reference value, relative biological effectiveness at 10%, 20%, 50% and 80% survival levels were given for the accelerated carbon ions. The results showed that carbon ions with LET of 125.5 keV/μm had a higher value of RBE at all the four survival levels than the carbon ions with other LETs. It was prompted that the maximum value of RBE for the V79 cell surviving as the biological endpoint emerged at the LET below 200 keV/μm for carbon ions.

关键词：放射生物学碳离子 V79细胞

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铬的形态分析研究与展望

冶金分析 2006年第5期26卷 38-43页

作者：李建文黄坚中南大学化学化工学院湖南长沙410083 中南大学化学化工学院

综述了近5年来铬的形态分析的新进展。讨论了水样、沉积物和生物样品中铬形态分析的预处理方法,概括了当前常用的分离富集方法。介绍了电化学方法,分光光度法,原子光谱法等在铬的形态分析中的新应用,并展望了铬的形态分析的发展前景。

关键词：铬形态分析综述

Dietary Iodine Intake in the Chinese Population

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Biomedical and Environmental Sciences 2011年第6期24卷 617-623页

作者： SUI Hai Xia li jian wen MAO Wei Feng ZHU jiang Hui HE Yu Na SONG Xiao Yu MA Ning ZHANG Lei liU Sa Na liU Zhao Ping li Feng Qin National Institute of Nutrition and Food Safety China CDC Beijing 100021 China

Objective To evaluate dietary iodine intake and its potential risks among the Chinese population Methods Individual dietary iodine intake was calculated using food consumption data multiplying by iodine concentration in foods, table salt and drinking water, followed by summing, and then compared with the corresponding age-specific reference values, including Upper Intake Level （UL） and Recommended Nutrient Intake （RNI）. Results In areas with water iodine concentration （Wl） lower than 150 ug/L, 80.8% of residents had iodine intake between the RNI and UL, 5.8% higher than UL, and the remaining （13.4%） lower than RNI if iodized salt was consumed. However, in the uniodized salt consumption scenario, only 1.0% of residents between RNI and UL, 1.4% higher than UL, and a large part of residents （97.6%） lower than RNI. In areas with Wl higher than 150 ug/L ,all residents had iodine intake between RNI and UL if iodized salt was consumed, except 10.5% and 24.9% of residents higher than UL in areas with Wl at 150-300 ug/L and higher than 300 ug/L respectively. However, in the uniodized salt consumption scenario, only 1.5% and 1.7% of residents had higher iodine intake than UL respectively. Conclusion The findings suggested that in general, the dietary iodine intake by the Chinese population was appropriate and safe at the present stage. People in areas with WI lower than 150 ug/L were more likely to have iodine deficiency. While people in areas with WI higher than 150 ug/L were more likely to have excessive iodine intake if iodized salt was consumed.

关键词： Iodine Exposure assessment Drinking water Iodine Dietary Iodine Intake

Low dose effects on cultured mammalian cells...

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Nuclear Science and Techniques 2000年第4期11卷 276-279页

作者： WANG Ju-Fang, li wen-jian, ZHOU Guang-Ming, HE Jing, li Qiang, DANG Bing-Rong, li Xing-lin, XIE Hong-Mei, WEI Zeng-Quan (Institute of Modern Physics, the Chinese Academy of Sciences, Lanzhou 730000) 中科院近代物理所甘肃兰州 730000

The low dose effects induced by carbon ions on Chinese hamster V79 cells and murine melanoma B16 cells were investigated in this paper. Both cell lines were divided into four groups for irradiation: (1) control, (2) 0.02 Gy or 0.05 Gy(D1), (3) 1 Gy(D2), (4) D1+D2. The survivors and micronuclei were studied as biological endpoints. The results of group (1) and group (2) showed that there were no obvious differences on micronucleus frequency but there were significant increases when irradiation dose was 0.02Gy on colony formation efficiency. Although low dose ion irradiation could not contribute to DNA damages, it could enhance the colony formation efficiency. In the study of group (3) and (4), when the ion dose was 0.02 Gy, there were evident increases on surviving fraction and decreases on micronucleus frequency, but there were no statistical changes on these endpoints when the ion dose was 0.05Gy. This meant that high LET radiation could induce the adaptive response of cultured cells, furthermore, in the range of inducing ion dose , low dose irradiation was more profitable than high dose one.

关键词：哺乳动物细胞 DNA 离子辐射低剂量效应辐射效应碳离子