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Explanation of the mechanism of carcinogenesis and syntheses of anticancer agents with high selectivity

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Science china Chemistry 2006年第1期49卷 44-62页

作者： DAI Qianhuan1,2 1. center of Chemistry and Bioengineering of Cancer research, beijing Polytechnic University (Now known as beijing Univer-sity of Technology), beijing 100022, china 2. center of Environmental Sciences, Peking University, beijing 100871, china center of Chemistry and Bioengineering of Cancer research Beijing Polytechnic University Beijing China center of Environmental Sciences Peking University Beijing China

In 1979, the mechanism of chemical carcinogenesis, a challenging anddifficult scientific problem pending for a number of years, was explained by Dai Qianhuan. Themechanism named di-region theory predicted that a carcinogen always metabolizes to form a specialbi-functional alky-lating agent. This agent induces cross-linkages between the complementary basepairs in DMA and switches on initial mutageneses in genomes including point and frameshiftmutations. This, in turn, induces further deep mutageneses including the production of variouschimeric chromosomes, deletions and other aberrations found in genomes. In the end this initiatescarcinogenesis of the whole cell through the reverse transcription mechanism after a lengthyincubation period. Recently, this laboratory has verified that physical carcinogenesis, includingthe oncogenesis induced by radiation and asbestos as well as the carcinogenesis induced byendogenous factors such as estrogen or diethyl-stilbestrol switch on carcinogenesis by inducing theformation of cross-linkages between the complementary base pairs in DNA. Di-region theory has nowbeen supported by many experimental observations such as mutational spectra of various *** potential for carcinogenesis, teratogenesis, sterility and mutagenesis lumped together asgenetic toxicity appears to originate almost uniformly from the cross-linking between complementarybases, i.e. malignant cross-linking, which is in accordance with di-region theory. Other forms ofcross-linking between non-complementary bases, benign cross-linkings, show bi-functional alkylationanticancer activity but lack genetic toxicity. The predictable design and synthesis of a highselectivity anticancer agent with high efficacy and low genetic toxicity, a goal long pursued incancer chemotherapy, have been realized for the first time in this laboratory by inhibitingmalignant and heightening benign cross-linking using the principles of di-region theory. A series ofpatented new anticanc

关键词： mechanism of carcinogenesis, di-region theory, minoplatin, selectivity of anticancer agent, cross-linking between DNA bases, anticancer platinum complexes, predictive design of anticancer agent, second generation anticancer agent.

Characteristics and Implication of Double-Circular Slope Break

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地学前缘 2009年第S1期16卷 149-150页

作者： Xuebin Du~1,Xinong Xie~1,Jianye Ren~1,Yongchao Lu~1,Tao Cheng~2,Ming Su~1 1.Faculty of Earth Resources,china University of Geosciences(Wuhan),Wuhan 430074,china. 2.beijing research center of cnooc,beijing 100027,china

The characteristics of slope break during depression stage in the Songliao Basin of NE china are analyzed. It is indicated that double flexure slope breaks extend in a circle across the *** is nominated the inner slop... 详细信息

关键词： Songliao Basin slope break sedimentary system control

In situ adsorption-catalysis system for the removal of o-xylene over an activated carbon supported Pd catalyst

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Journal of Environmental Sciences 2009年第7期21卷 985-990页

作者： HUANG Shaoyong, ZHANG Changbin, HE Hong research center for Eco-Environmental Sciences, Chinese Academy of Sciences, beijing 100085, china. research center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

An activated carbon （AC） supported Pd catalyst was used to develop a highly efficient in situ adsorption-catalysis system for the removal of low concentrations of o-xylene. In this study, three kinds of Pd/AC catalysts were prepared and tested to investigate the synergistic efficiency between adsorption and catalysis for o-xylene removal. The Pd/AC catalyst was first used as an adsorbent to concentrate dilute o-xylene at low temperature. After saturated adsorption, the adsorbed o-xylene was oxidized to CO2 and H20 by raising the temperature of the catalyst bed. The results showed that more than 99% of the adsorbed o-xylene was completely oxidized to CO2 over a 5% Pd/AC catalyst at 140℃. Brunauer-Emmett-Teller （BET） analysis, scanning electron microscopy （SEM）, temperatureprogrammed desorption （TPD）, and temperature-programmed oxidation （TPO） were applied to investigate the physical properties of o-xylene adsorption-desorption and the in situ adsorption-catalysis activity of the AC support and Pd/AC catalyst. A synergistic relationship between the AC support and the active Pd species for the removal of low concentrations of o-xylene was established.

关键词： in situ adsorption-catalysis Pd/AC volatile organic compounds

Combined toxicity of copper and cadmium to six rice genotypes (Oryza sativa L.)

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Journal of Environmental Sciences 2009年第5期21卷 647-653页

作者： HUANG Yizong, HU Ying, LIU Yunxia research center for Eco-Environmental Sciences, Chinese Academy of Sciences, beijing 100085, china. research center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Accumulations of copper （Cu） and cadmium （Cd） in six rice cultivars （94D-22, 94D-54, 94D-64, Gui630, YY-1, and KY1360） were evaluated through exposure to heavy metal contamination （100 mg/kg Cu, 1.0 mg/kg Cd, and 100 mg/kg Cu ＋ 1.0 mg/kg Cd） in a greenhouse. The dry weights of shoot and root, concentrations of Cu and Cd in plant tissues and the Cu, Cd, P, Fe concentrations in the root surface iron plaques were analyzed eight weeks later after treatment. The results indicated that the plant biomass was mainly determined by rice genotypes, not Cu and Cd content in soil. Separated treatment with Cu/Cd increased each metal level in shoot, root and iron plaques. Soil Cu enhanced Cd accumulation in tissues. In contrast, Cu concentrations in shoot and root was unaffected by soil Cd. Compared to single metal contamination, combined treatment increased Cd content by 110.6%, 77.0%, and 45.2% in shoot, and by 112.7%, 51.2% and 18.4% in root for Gui630, YY-1, and KY1360, respectively. The content level of Cu or Cd in root surface iron plaques was not affected by their soil content. Cu promoted Fe accumulation in iron plaques, while Cd has no effect on P and Fe accumulation in it. The translocation of Cu and Cd from iron plaques to root and shoot was also discussed. These results might be beneficial in selecting cultivars with low heavy metal accumulation and designing strategies for soil bioremediation.

关键词： Cu Cd combined contamination soil uptake accumulation root surface iron plaques

Adsorption-desorption behavior of acetochlor to soils in the presence of some environmental substances

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Journal of Environmental Sciences 2002年第2期14卷 269-276页

作者： YE Chang ming, LEI Zhi fang (research center for Eco Environmental Sciences, Chinese Academy of Sciences, beijing 100085, china. research center for Eco-Environmental Sciences Chinese Academy of Sciences 北京 100085

The behavior of herbicide acetochlor adsorption desorption to soil in the presence of humic acid (HA), anionic surfactant sodium dodecylbenzene sulfonate (SDBS), cationic surfactant hexadecyltrimethyl ammonium bromide (HDAB) and NH 4NO 3 as a chemical fertilizer was studied. Observed acetochlor adsorption isotherm were well described using Freundlich isotherm equation, from which the desorption isotherm equation has been deduced. The deduced equation can more directly describe acetochlor desorption process. The results showed that the enhance of acetochlor adsorption capacity by solid HA was greater than by soluble HA. The presence of NH 4NO 3 can slightly enhance acetochlor adsorption to soil by comparison with that measured in NH 4NO 3 free solution. In soil water system, surfactant acetochlor interaction is very complex, and the surfactant adsorptions as well as acetochlor adsorption need to be considered. When acetochlor soil suspensions contained lower concentration SDBS or HDAB (40 mg/L), K f for acetochlor adsorption was decreased in comparison to that measured in SDBS or HDAB free solution. When acetochlor soil suspensions contained higher concentration SDBS or HDAB (corresponding 1400 mg/L or 200 mg/L), K f for acetochlor adsorption was increased in comparison to that measured in SDBS or HDAB free solution.

关键词： adsorption desorption acetochlor humic acid surfactants ammonium nitrate soil

Dynamic analysis and assessment for sustainable development

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Journal of Environmental Sciences 2002年第1期14卷 88-94页

作者： SHI Xiao\|qing (Department of Systems Ecology, research center for Eco\|Environmental Sciences, Chinese Academy of Sciences, beijing 100085, china. ) Department of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences 北京 100085

The assessment of sustainable development is crucial for constituting sustainable development strategies. Assessment methods that exist so far usually only use an indicator system for making sustainable judgement. These indicators rarely reflect dynamic characteristics. However, sustainable development is influenced by changes in the social\|economic system and in the eco\|environmental system at different times. Besides the spatial character, sustainable development has a temporal character that can not be neglected; therefore the research system should also be dynamic. This paper focuses on this dynamic trait, so that the assessment results obtained provide more information for judgements in decision\|making processes. Firstly the dynamic characteristics of sustainable development are analyzed, which point to a track of sustainable development that is an upward undulating curve. According to the dynamic character and the development rules of a social, economic and ecological system, a flexible assessment approach that is based on tendency analysis, restrictive conditions and a feedback system is then proposed for sustainable development.

关键词： sustainable development assessment dynamic analysis

Numerical experiments for the impacts of temperature and precipitation variation on the growth and development of winter wheat

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Journal of Environmental Sciences 1993年第2期5卷 194-200页

作者： Zhang YuAgrometeorological research center, Chinese Academy of Meteorological Sciences, beijing 100081, china Agrometeorological research center Chinese Academy of Meteorological Sciences Beijing 10081 China. China

The growth process of winter wheat was simulated by CERES-wheat model assuming the daily temperature increase -1, 0,1, 2℃ and daily precipitation increase -20, -10, -5, 0, 5, 10, and 20 percent, respectively. The case study site is Zhenjiang City of Jiangsu Province in the east china. Simulation results show that the impacts of temperature variation on winter wheat is stronger than that of precipitation. Climate warming would speed development rate and shorten phonological period. In general, the adverse effect of climate change on grain yield is greater than that of its beneficial effect, especially when the climate becoming cooler and dryer. The increase of temperature and decrease of precipitation would reduce the plant extractablc soil water content.

关键词： climate change winter wheat CERES-wheat model.

The numerical simulation of Pacific Ocean circulation with five-level model

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Acta Oceanologica Sinica 1993年第3期12卷 395-404页

作者： Xing Runan and Chao Jiping beijing Meteorological College, beijing 100081 china National research center for Marine Environmental Forecasts, beijing 100081, china

A five-level oceanic primitive equation model has been developed. This model is integrated numerically with annual mean wind stress and heat flux at sea surface for 30 a. The ocean circulations tend to quasi-stability. The simulated results show that the computed annual mean currents and sea surface temperature agree well with the observations.

关键词： heat The numerical simulation of Pacific Ocean circulation with five-level model

Multi-level decollement zones and detachment deformation of Longmenshan thrust belt,Sichuan Basin,southwest china

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Science china Earth Sciences 2008年第S2期51卷 32-43页

作者： TANG LiangJie1,2,3,YANG KeMing4,JIN WenZheng1,2,3,L ZhiZhou4 & YU YiXin1,2,3 1 State Key Laboratory of Petroleum Resource and Prospecting,china University of Petroleum,beijing 102249,china 2 Key Laboratory for Hydrocarbon Accumulation Mechanism,china University of Petroleum,Ministry of Education,beijing 102249,china 3 Basin and Reservoir research center,china University of Petroleum,beijing 102249,china 4 Southwest Division Company,SINOPEC,Chengdu 610081,china State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing China Key Laboratory for Hydrocarbon Accumulation Mechanism China University of Petroleum Ministry of Education Beijing China Basin and Reservoir research center China University of Petroleum Beijing China Southwest Division Company SINOPEC Chengdu China

As is well known that many decollement layers were developed in the Longmenshan thrust belt,Si-chuan Basin,china. Through field investigation,explanation of seismic profiles and analysis of the balanced sections,we can divide the decollement zones into 3 categories: (1) the deep level decolle-ment zones,including the crust-mantle decollement layer,intracrustal decollement layer,and presinian basal decollement layer. The main structural styles of their deformation are the crust-mantle decoup-ling detachment deformation,the basal ductile shear deformation,etc.; (2) the middle level decollement zones,including the Cambrian-Ordovician decollement layer,the Silurian decollement layer,etc.,the main structural styles of their deformation are the isopachous fold,the angular fold,the saddle struc-ture,and the combination styles of them; and (3) the shallow level decollement zones,including the Xujiahe Formation decollement layer of Upper Triassic and the Jurassic decollement layers,the main structural styles of their deformation are the thrust-nappe tectonic,the pop-up,the triangle zone ,the duplex,etc. Multi-level decollement zones not only made the Longmenshan thrust belt develop many different deformation styles from deep place to shallow place,but also made some local areas have the superimposition of the tectonic deformation apparently. This study indicates that the multi-level de-collement zones have a very important effect on the shaping and evolution of the Longmenshan thrust belt.

关键词： decollement layer structural styles multi-level decollement zones Longmenshan thrust belt