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Role of dNTPs in Mutagenesis

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Biomedical and Environmental sciences 1998年第4期11卷 345-353页

作者： LEI HAI-xiN LI ZHONG-SHENG xiE DA-YING LIU BING-CI ZUO JIN AND FANG fu-DE (institute of Basic Medical sciences, chinese academy of Medical sciences (CAMS), beijing 100005, china) (institute of Occupotional Medicine, chinese academy of Preventive Me institute of Basic Medical sciences Chinese Academy of Medical Sciences (CAMS) Beijing China.

The induced mutation frequency by alkylating mutagen glycldyl methacrylate (GMA) and N-methyl-N'- nitro- N-nitrosoguanidine (MNNG) was investigated with or without perturbation of deoxyribenucleoside triphosphate (dNTP)pools; the influence of short treatment at different concentrations of GMA or MNNG on dNTP pools was also explored. The results indicated that the induced mutation frequency increased greatly at high dosages of mutagen (GMA~ 64 μg/ml, MNNG~ 8 μg/ml) and the perturbation on dNTP pools was carried out before the treatment of mutagen; the short treatment with mutagen could induce distinct fluctuations of dNTP pools, but different mutagen might have different effects on dNTP *** to the results of the present study and other reports in literature, we conclude that dNTP pools may be the targets of alkylating mutagens and the fluctuations of dNTP pools are closely associated with mutagenesis

关键词： DNA Res Role of dNTPs in Mutagenesis

Modeling the climate effects of different subregional uplifts within the Himalaya-Tibetan Plateau on Asian summer monsoon evolution

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chinese Science Bulletin 2012年第35期57卷 4617-4626页

作者： ZHANG Ran 1,JIANG DaBang 1,2,3,LIU xiaoDong 4 & TIAN ZhiPing 2,5 1 Climate Change Research Center,chinese academy of sciences,beijing 100029,china 2 Nansen-Zhu International Research Centre,institute of Atmospheric Physics,chinese academy of sciences,beijing 100029,china 3 Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,chinese academy of sciences,beijing 100029,china 4 State Key Laboratory of Loess and Quaternary Geology,institute of Earth Environment,chinese academy of sciences,xi’an 710075,china 5 Graduate University of chinese academy of sciences,beijing 100049,china 1. Climate Change Research Center Chinese Academy of Sciences Beijing 100029 China 2. Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 3. Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Chinese Academy of Sciences Beijing 100029 China 4. State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 5. Graduate University of chinese academy of sciences Beijing 100049 China

Considering the different uplifting time of different subregions of the Himalaya-Tibetan Plateau(TP),a series of numerical simulations have been conducted with the Community Atmosphere Model(CAM4) developed at the National Center for Atmospheric Research to explore the effects of the phased tectonic uplift of the Himalaya-TP on the evolution of Asian summer *** results show that the uplifts of the Himalaya and northern TP significantly affect the evolutions of South Asian summer monsoon and northern East Asian summer monsoon *** is,the tectonic uplift of the Himalaya intensifies the South Asian summer monsoon circulation and increases the precipitation in South Asia,whereas the uplift of the northern TP intensifies the northern East Asian summer monsoon circulation and increases the precipitation in northern East *** with previous simulations,current comparative analyses of modeling results for different subregional uplifts within the Himalaya-TP help deepen our understanding of the evolutionary history of Asian monsoons.

关键词：青藏高原隆升喜马拉雅亚洲季风高原气候夏季季风次区域隆起演化建模

Early systemic anticoagulation reduces hospital readmission in acute necrotizing pancreatitis patients:A retrospective cohort study

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 77-82页

作者： Wen-Jian Mao Jing Zhou Guo-fu Zhang Fa-xi Chen Jing-Zhu Zhang Bai-Qiang Li Lu Ke Wei-Qin Li Department of Critical Care Medicine Jinling HospitalNanjing Medical UniversityNanjing 210002China Department of Critical Care Medicine Jinling HospitalMedical School of Nanjing UniversityNanjing 210002China National institute of Healthcare Data Science Nanjing UniversityNanjing 210010China

Background:Early systemic anticoagulation(SAC)is a common practice in acute necrotizing pancreatitis(ANP),and its impact on in-hospital clinical outcomes had been ***,whether it affects long-term outcomes is *** study aimed to evaluate the effect of SAC on 90-day readmission and other long-term outcomes in ANP ***:During January 2013 and December 2018,ANP patients admitted within 7 days from the onset of abdominal pain were *** primary outcome was 90-day readmission after *** proportional-hazards regression model and mediation analysis were used to define the relationship between early SAC and 90-day ***:A total of 241 ANP patients were enrolled,of whom 143 received early SAC during their hospitalization and 98 did *** who received early SAC experienced a lower incidence of splanchnic venous thrombosis(SVT)[risk ratio(RR)=0.40,95%CI:0.26-0.60,P<0.01]and lower 90-day readmission with an RR of 0.61(95%CI:0.41-0.91,P=0.02)than those who did *** the quality of life,patients who received early SAC had a significantly higher score in the subscale of vitality(P=0.03)while the other subscales were all comparable between the two *** Cox regression model showed that early SAC was an independent protective factor for 90-day readmission after adjusting for potential confounders with a hazard ratio of 0.57(95%CI:0.34-0.96,P=0.04).Mediation analysis showed that SVT mediated 37.0%of the early SAC-90-day readmission ***:The application of early SAC may reduce the risk of 90-day readmission in the survivors of ANP patients,and reduced SVT incidence might be the primary contributor.

关键词： Anticoagulation Splanchnic venous thrombosis Acute necrotizing pancreatitis Readmission Long-term outcomes

Ultra-high spatio-temporal resolution imaging with parallel acquisition-readout structured illumination microscopy(PAR-SIM)

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Light(Science & Applications) 2024年第6期13卷 1140-1158页

作者： xinzhu Xu Wenyi Wang Liang Qiao Yunzhe fu xichuan Ge Kun Zhao Karl Zhanghao Meiling Guan xin Chen Meiqi Li Dayong Jin Peng xi Department of Biomedical Engineering College of Future TechnologyPeking UniversityBeijing100871China Wallace H.Coulter Dept.of Biomedical Engineering Georgia Institute of Technology and Emory UniversityAtlanta30332GAUSA National Biomedical Imaging Center Peking UniversityBeijing100871China Department of Biomedical Engineering College of EngineeringSouthern University of Science and TechnologyShenzhen518055GuangdongChina Airy Technologies Co. Ltd.Beijing100086China Eastern institute for Advanced Study Eastern Institute of TechnologyNingboZhejiang315200China School of Life Science Peking UniversityBeijing100871China institute for Biomedical Materials and Devices(IBMD) Faculty of ScienceUniversity of Technology SydneySydneyNSW2007Australia

Structured illumination microscopy(SIM)has emerged as a promising super-resolution fluorescence imaging technique,offering diverse configurations and computational strategies to mitigate phototoxicity during real-time imaging of biological *** efforts to enhance system frame rates have concentrated on processing algorithms,like rolling reconstruction or reduced frame reconstruction,or on investments in costly sCMOS cameras with accelerated row readout *** this article,we introduce an approach to elevate SIM frame rates and region of interest(ROI)coverage at the hardware level,without necessitating an upsurge in camera expenses or intricate ***,parallel acquisition-readout SIM(PAR-SIM)achieves the highest imaging speed for fluorescence imaging at currently available detector *** using the full frame-width of the detector through synchronizing the pattern generation and image exposure-readout process,we have achieved a fundamentally stupendous information spatial-temporal flux of 132.9 MPixels·s^(−1),9.6-fold that of the latest techniques,with the lowest SNR of−2.11 dB and 100 nm ***-SIM demonstrates its proficiency in successfully reconstructing diverse cellular organelles in dual excitations,even under conditions of low signal due to ultra-short exposure ***,mitochondrial dynamic tubulation and ongoing membrane fusion processes have been captured in live COS-7 cell,recorded with PAR-SIM at an impressive 408 *** posit that this novel parallel exposure-readout mode not only augments SIM pattern modulation for superior frame rates but also holds the potential to benefit other complex imaging systems with a strategic controlling approach.

关键词： hardware illumination resolution

Environmental characteristics of Mid-Holocene recorded by lacustrine sediments from Lake Daihai, north environment sensitive zone, china

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Science china Earth sciences 2006年第9期49卷 968-981页

作者： SUN Qianli1,2, ZHOU Jie1, SHEN Ji3, CHEN Peng1,2, WU Feng1,2 & xiE xiuping1,2 1. State Key Lab of Loess and Quaternary Geology, institute of Earth Environment, chinese academy of sciences, xi’an 710075, china 2. Graduate University of chinese academy of sciences, beijing 100039, china 3. Nanjing institute of Geography and Limnology, chinese academy of sciences, Nanjing 210008, china 1. State Key Lab of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 2. Graduate University of chinese academy of sciences Beijing 100039 China 3. Nanjing institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

Climate proxies, such as total organic carbon and nitrogen (TOC, TN), carbonate content (CaCO3), grain-size and pollen of the sediment core retrieved from enclosed Lake Daihai which lies in the north china environment sensitive zone are analyzed to reconstruct the environment evolution of the area based on high-resolution radiocarbon chronology. The results reveal that the TOC and TN contents of the sediments correlate well with pollen percentage and pollen flux variations during the Holocene, and both reach their peak values simultaneously at 6.7―3.5 ka BP (calendar age, 7.6―3.6 ka BP). Since 6.7 ka BP, both the CaCO3 and organic matter contents of the core have simultaneous variations, and their high values also occur during 6.7―3.5 ka BP. While during 9.0―6.7 ka BP (calendar age, 10―7.6 ka BP) relatively lower level of organic matter content and pollen flux corre- spond to the higher level of carbonate content. The above relations suggest that during 6.7―3.5 ka BP, the productivity and effective precipitation were greatly improved in the lake drainage area, and this would probably strengthen the hydrodynamic conditions, enhancing organic matter, pollen and carbonate inputs from terrestrial sources. Such processes would account for the enrichment of both organic matter and carbonate in the sediments. While during 9.0―6.7 ka BP, the lower level of or- ganic matter, pollen flux but high carbonate content show depressed productivity and declined vege- tation coverage. The higher carbonate content at this stage would have probably resulted from the higher evaporation ratio of the lake water under relatively drier climate conditions. Therefore, it is in- ferred that during 6.7―3.5 ka BP, the climate was more humid with abundant rainfalls and vegetation was more flourishing in the Lake Daihai area. This can be seen as Holocene Climate Optimum (HCO). As a result, this has evident discrepancies with the traditional notion that the HCO occurs at Early Holocene or early Mid

关键词： Lake Daihai, Mid-Holocene, lacustrine sediments, environmental characteristics.

function of chymase in the heart angiotensin Ⅱ formation in transgenic mice

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chinese Science Bulletin 2001年第11期46卷 922-925页

作者： LI Peng & CHEN LanyingCardiovascular institute & fu Wai Hospital, chinese academy of Medical sciences & Peking Union Medical College, beijing 100037, china Cardiovascular institute & fu Wai Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China

The myosin light chain 2 promoter-human heart chymase (MLC2-hChymase) transgenic mice founded by our laboratory were used as the model to study the function of chymase in the heart angiotension Ⅱ (Ang Ⅱ) formation and heart remodeling. Tissue-specific expression of human heart chymase gene and transcriptional expression of type Ⅰ and type Ⅲ collagens genes were analyzed by RT-PCR. Activities of chymase, ACE and the levels of Ang Ⅱ in heart and plasma were determined with radioimmunoas-say (RIA) kit. Activity of heart matrix metalloproteinase-9 (MMP-9) was detected using gelatin zymography. The cardiac hypertrophic phenotypes were also observed with the physiological and morphological methods. The results in the MLC2-hChymase transgenic mice indicated: ( i ) human heart chymase gene was expressed specially in the heart; (u) heart chymase activity increased markedly in the transgenic mice vs non-transgenic mice (control) (0.27±0.07 U/mg vs. 0.15±0.02 U/mg, P<0.05) with no significant difference in

关键词： chymase transgenic mice angiotensin Ⅱ heart remod- eling collagen.

IDENTIFICATION OF BOTH CLOSED-AND OPEN-LOOP STOCHASTIC SYSTEM WHILE STABILIZING IT

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Journal of Systems Science & Complexity 2002年第1期15卷 1-17页

作者： CHEN Hanfu(Han-fu Chen) (Laboratory of Systems and Control,institute of Systems Science, academy of Mathematics and Systems Science,chinese academy of sciences, beijing 100080, china) institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Laboratory of Systems and Control CAS 北京 100080

This paper proposes a recursive algorithm estimating coefficients of the linear stochastic control system(ARX system) driven by a martingale difference sequence, while adaptively stabilizing the system without introducing external excitation signal. The system is allowed to be unstable and of nonminimum-phase. The estimates derived for the coefficients of both closed-loop and open-loop systems are strongly consistent.

关键词： System identification ARX system unstable nonminimum-phase strong consistency.

Digital image analysis of palaeoenvironmental records and applications

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chinese Science Bulletin 2002年第23期47卷 1957-1963,2025-2026页

作者： SUN Donghuai1,2, LIU Yu2 & TAN Ming31. South china Sea institute of Oceanology, chinese academy of sciences. Guangzhou 510301, china 2. State Key Laboratory of Loess and Quaternary Geology, Earth Environmental institute, chinese academy of sciences, xi’an 710075, china 3. institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china South china Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China State Key Laboratory of Loess and Quaternary Geology Earth Environmental Institute Chinese Academy of Sciences Xi’an China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

关键词： digital image environmental records.

Neogene eolian deposits within the West Qinling Mountains:Climatic and tectonic implications

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chinese Science Bulletin 2010年第15期55卷 1483-1487页

作者： GE JunYi 1,2 & GUO ZhengTang 3 1 State Key Laboratory of Loess and Quaternary Geology (SKLLQG),institute of Earth Environment,chinese academy of sciences,xi’an 710075,china 2 Graduate University of chinese academy of sciences,beijing 100049,china 3 Key Laboratory of Cenozoic Geology and Environment,institute of Geology and Geophysics,chinese academy of sciences,beijing 100029,china State Key Laboratory of Loess and Quaternary Geology (SKLLQG) Institute of Earth Environment Chinese Academy of Sciences Xi''an 710075 China Graduate University of chinese academy of sciences Beijing 100049 China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

The Qinling Mountains constitute a key climate barrier between southern and northern *** recent investigations revealed widely spread eolian deposits of Neogene age mantling the piedmont highlands of the intermountain basins within West ***-mammalian fossils dated a 150.2 m section (NL-VI) near xihe for the late Miocene to Pliocene (～10-4 Ma).Soil micromorphology,grain-size and geochemical analysis consistently define typical loess-soil alternations for the upper (0-66 m) and lower (98-150.2 m) parts of the section,with the middle section (66-98 m) having been affected by episodic slope *** results add important insights to the earlier studies about the widespread eolian deposition in northern china during the Miocene,prior to 8 *** also suggest that the basic configuration of the ridges and inter-ridge basins of West Qinling has already formed by ～10 *** well-preserved eolian deposits are unlikely to support intense substratum deformation and rapid uplift of West Qinling since the late Miocene.

关键词：秦岭山脉风尘堆积构造意义气候新近纪晚中新世地球化学分析风尘沉积