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Probability parametric imaging with DCE-MRI data to identify prostate cancer in the peripheral zone

Progress in Natural Science:Materials International 2006年第9期16卷 948-953页

作者： HUANG Xinrui, WANG Qiang, XU Yufeng, WANG Xiaoying and BAO Shanglian ( The key laboratory of Medical Physics and Engineering, Peking university, beijing 100871, china.The Medical School of Peking university, beijing 100083, china.3. The First Hospital of Peking university, beijing 100034, china. The key laboratory of Medical Physics and Engineering Peking University Beijing 100871 China The Medical School of Peking university Beijing 100083 China The First Hospital of Peking university Beijing 100034 China

To quantitatively analyze prostate dynamic contrast-enhanced magnetic resonance images (DCE-MRI), a retrospective study was carried out to construct a mathematical model to predict whether a lesion is cancerous or not. With known diagnosis of 52 re-gions-of-interest (10 malignant, 26 benign and 16 normal) in peripheral zone (PZ) of prostate from 18 patients undergoing needle biopsy and 8 normal volunteers, we combined feature parameters (k1, k2 and tp) from the linear-slope model with logistic regression to determine the statistical probability model. Prostate cancerous probability maps were derived using the model on each subject to examine the correlation between the model-based prediction and the known diagnosis. Compared the model prediction results of 52 regions-of-interest with the histopathologic results, the total agreement rate was 90.4 % ; the agreement rate was 60 % for the malignant and 97. 6 % for the nonmalignant. The diagnostic results only referencing the probability maps by two radiologists showed a high agreement in tissue characteristics and lesion location with the combining results from other diagnostic techniques such as PSA (prostate specific antigen) level and MRS (magnetic resonance spectroscopy) .

关键词： time-intensity curve prostate DCE-MRI logistic regression probability parametric image.

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Narrow line Seyfert 1 galaxies: where are the broad line regions?

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Science china.Physics,Mechanics & Astronomy) 2010年第12期53卷 2307-2311,2339-2343页

作者： MAO WeiMing 1,2,3 , HU Chen 2 , WANG JianMin 2 , BIAN WeiHao 4 , ZHANG Shu 2 & ZHAO Gang 1 1 key laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, beijing 100012, china.2 key laboratory for Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, beijing 100049, china.3 Graduate university of the Chinese Academy of Sciences, beijing 100049, china.4 Department of Physics, Nanjing normal university, Nanjing 210011, china key laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing China key laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Graduate university of the Chinese Academy of Sciences Beijing China Department of Physics Nanjing Normal University Nanjing China

A sample consisting of 211 narrow line Seyfert 1 galaxies (NLS1s) with high quality spectra from the Sloan Digital Sky Survey (SDSS) is selected to explore where broad line regions are in these objects. We find that the Hβ profile can be fitted well by three (narrow, intermediate and broad) Gaussian components, and the FWHM ratios of the broad to the intermediate components hold a constant of 3.0 roughly for the entire sample. If the broad components originate from the region scaled by the well-determined Hβ reverberation mapping relation, we find that the intermediate components originate from the inner edge of the torus, which is scaled by dust K-band reverberation. We find that the IC and the BC are strongly linked dynamically, but the relation of their covering factors is much more relaxed, implying that both regions are clumpy.

关键词： black hole physics galaxies: evolution quasars: general

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An improved exponential filter for fast nonlinear registration of brain magnetic resonance images

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Progress in Natural Science:Materials International 2009年第6期19卷 759-767页

作者： Zhiying Long a, Li Yao a,b, Kewei Chen c, Danling Peng a a State key laboratory of Cognitive Neuroscience and learning, beijing normal university, beijing 100875, china.b School of Information Science and Technology, beijing normal university, beijing 100875, china.c Banner Alzheimer Institute (BAI) & Samaritan PET Center, Phoenix, AZ, USA State key laboratory of Cognitive Neuroscience and learning Beijing Normal University Beijing 100875 China School of Information Science and Technology Beijing Normal University Beijing 100875 China Banner Alzheimer Institute (BAI) & Samaritan PET Center Phoenix AZ USA

A linear elastic convolution filter was derived from the eigenfunctions of the Navier-Stokes differential operator by Bro-Nielsen in order to match images with large deformations. Due to the complexity of constructing the elastic convolution filter, the algorithm’s efficiency reduces rapidly with the increase in the image’s size. In our previous work, a simple two-sided exponential filter with high efficiency was proposed to approximate an elastic filter. However, its poor smoothness may degenerate the performance. In this paper, a new exponential filter was constructed by utilizing a modified nonlinear curve fitting method to approximate the elastic filter. The new filter’s good smoothness makes its performance comparable to an elastic filter. Its simple and separable form makes the algorithm’s speed faster than the elastic filter. Furthermore, our experiments demonstrated that the new filter was suitable for both the elastic and fluid models.

关键词： Exponential filter Nonlinear Registration Magnetic resonance imaging

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A PSTAIRE CDK-like protein localizes in nuclei and cytoplasm of Physarum polycephalum and functions in the mitosis

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Cell Research 2004年第2期14卷 169-175页

作者： Gui Ying LI~(1,2), Miao XING~(1,*), Bo HU~(1,3) ~1College of Life Science, Shenzhen key laboratory of Microbial Gene Engineering, Shenzhen university, Shenzhen 518060, china. ~2Department of Immunology, School of Basic Medical Sciences, Jilin university, Changchun 130021, china.~3Institute of Genetics and Cytology, Northeast normal university, Changchun 130024, china. College of Life Science Shenzhen Key Laboratory of Microbial Gene Engineering Shenzhen University Shenzhen China Department of Immunology School of Basic Medical Sciences Jilin University Changchun China Institute of Genetics and Cytology Northeast Normal University Changchun China

CDKs play key roles in controlling cell cycle progression in all eukaryotes. In plants, multiple CDKs are present, among which the best characterized CDKs are PSTAIRE CDKs. In this study, we carried out Western blot, immunoelectron microscopy and antibody treatment with an anti-PSTAIRE monoclonal antibody to explore the subcellular localization and functions of PSTAIRE CDKs in Physarum polycephalum. The results of Western blot and immunoelectron microscopy showed that in P. polycephalum, a PSTAIRE CDK-like protein was 34 kD in molecular weight and located in both nuclei and cytoplasm. In nuclei, the protein was mainly associated with chromosomes and nucleoli. The expression of the PSTAIRE CDK-like protein in both the plasmodia and nuclei showed little fluctuation through the whole cell cycle. When treated with an anti-PSTAIRE monoclonal antibody at early S phase, the cells were arrested in S phase, and the mitotic onset of P. polycephalum was blocked for about 1 h when treated at early G2 phase. Our dat

关键词： PSTAIRE CDK-like protein Physarum polycephalum mitosis immunoelectron microscopy.

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Cloning and sequencing of nifBHDKENX genes of Paenibacillus massiliensis T7 and its nif promoter analysis

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Science china.Life Sciences) 2006年第2期49卷 115-122页

作者： ZHAO Hongxin1,2,3, XIE Baoen2 & CHEN Sanfeng1,2 1. State key laboratory for Agrobiotechnology and Biological School, china.Agricultural university, beijing 100094, china.2. key laboratory for Agro-Microbial Resource and Application of Agriculture Ministry, china.Agricultural university, beijing 100094, china.3. Chemical and Biological School, ShenYang normal university, Shenyang 110034, china State key laboratory for Agrobiotechnology and Biological School China Agricultural University Beijing China key laboratory for Agro-Microbial Resource and Application of Agriculture Ministry China Agricultural University Beijing China Chemical and Biological School ShenYang Normal University Shenyang China

A 324 bp of nifH fragment was PCR amplified from Paenibacillus massiliensis T7 using the universal degenerate primers. The PCR-amplified nifH fragment was labeled with DIG; then used as a probe in Southern blot analysis. Southern blot result showed that there were two positive signals, indicating that there might be two copies of nifH in P. massiliensis T7. A total of 10254 bp DNA sequence containing purD; nifBHDKENX was obtained by five rounds of inverse-PCR amplification. The predicted proteins of nifBHDKENX had high homology with those from other nitrogen-fixing bacteria. Only one putative σ[54]-dependent promoter sequence was detected upstream of the nifB gene; nifBHDKENX were likely to be organized in one operon. Assays of β-galactosidase activity of P. massiliensis T7PB carrying a nifB-lacZ fusion under different concentrations of NH4 [+]; O2 showed that the expression of nifB-lacZ was strongly inhibited by O2.

关键词： Paenibacillus massiliensis T7, nifBHDKENX, nifB-lacZ, inverse-PCR.

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Scale effects of leaf area index inversion based on environmental and disaster monitoring satellite data

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Science china.Earth Sciences 2010年第S1期53卷 92-98页

作者： ZHANG Hao1,LI XiaoWen1,2,CAO ChunXiang1,YANG Hua2,GAO MengXu1,3,ZHENG Sheng1,3,XU Min1,3,XIE DongHui2,JIA HuiCong1,JI Wei1,ZHAO Jian1,3,CHEN Wei1,3 & NI XiLiang1,3 1 State key laboratory of Remote Sensing Science,Jointly Sponsored by Institute of Remote Sensing Applications,Chinese Academy of Sciences and beijing normal university,beijing 100101,china.2 State key laboratory of Remote Sensing Science,Jointly Sponsored by beijing normal university and Institute of Remote Sensing Applications of Chinese Academy of Sciences,beijing 100875,china.3 Graduate university of Chinese Academy of Sciences,beijing 100049,china State key laboratory of Remote Sensing Science Jointly Sponsored by Institute of Remote Sensing Applications Chinese Academy of Sciences and Beijing Normal University Beijing China State key laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing Applications of Chinese Academy of Sciences Beijing China Graduate university of Chinese Academy of Sciences Beijing China

The spatial distribution of sub-pixel components has an impact on retrieval accuracy,and should be accounted for when inverting a three-dimensional adiative transfer model to retrieve leaf area index(LAI).To investigate this effect,we constructed three realistic scenarios with the same LAI values and other properties,except that the simulated plants had different *** implemented the radiosity method to subsequently produce synthetic bidirectional reflectance factor(BRF) datasets based upon these simulated *** inversion was conducted using these data,which showed that spatial distribution affects retrieval *** inversion was also conducted for LAI based on charge-coupled device(CCD) data from the Environment and Disaster Monitor Satellite(HJ-1),which depicted both forest and drought-resistant crop land *** showed that heterogeneity in coarse-resolution remote sensing data is the main error source in LAI *** spatial distribution of global fractal dimension index,which can be used to describe the area of sub-pixel components and their spatial distribution modes,shows good consistency with the coarse resolution LAI inversion error.

关键词： HJ-1 leaf area index scale effect spatial distribution

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Cytotoxicity, apoptosis induction, and mitotic arrest by a novel podophyllotoxin glucoside, 4DPG, in tumor cells

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Acta Pharmacologica Sinica 2005年第8期26卷 1000-1008页

作者： Yi-lin QI~(2,4), Fan LIAO~(2,4), Chang-qi ZHAO~2, Yong-da LIN~2, Ming-xue ZUO~(2,3,5) ~2 College of Life Sciences, beijing normal university, beijing 100875 china.~3 key laboratory for Molecular Biology and Gene Engineering Drugs of beijing, beijing 100875, china College of Life Sciences Beijing Normal University Beijing China key laboratory for Molecular Biology and Gene Engineering Drugs of beijing Beijing China

Aim: To define the in vitro cytotoxic activities of 4-demethyl-picropodophyllotoxin 7'-O-β-D-glucopyranoside （4DPG）, a new podophyllotoxin glucoside. Methods: Antiproliferation activity was measured in several tumor cell lines by using the microculture tetrazolium MTT assays. Cell cycle distribution was analyzed using flow cytometry and mitosis index assays. Furthermore, transmission electron microscopy, TUNEL, DNA agarose electrophoresis, and activated caspase-3 were used to analyze the induction of apoptotic cell death. Moreover, intracellular changes in the cytoskeleton were detected using immunocytochemistry. Results: 4DPG effectively inhibited the proliferation of cancer cells （HeLa, CNE, SH-SY5Y, and K562 cell lines）. For the K562 cell line, the antiproliferation effect of 4DPG was much more potent than that of etoposide (IC50value: 7.79x10（-9） mol/L for 4DPG vs 2.23x 10（-5） mol/L for etoposide). Further, 4DPG blocked the cell cycle in the mitotic phase. The induction of apoptosis and elevated levels of activated caspase-3 were confirmed in cells treated with 4DPG. The microtubule skeleton of HeLa cells was disrupted immediately after treatment with 4DPG. Conclusion: The cytotoxicity of 4DPG is due to its inhibition of the microtubule assembly of cancer cells at a low concentration, thus inducing apoptosis. These properties qualify 4DPG to be a potential antitumor drug.

关键词： 4-demethyl-picropodophyllotoxin 7’-O-β-D-glucopyranoside podophyllotoxin flow cytometry microtubulin apoptosis

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Research on the damage of the Great Wall of Ming Dynasty in beijing by remote sensing

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Science china.Technological Sciences) 2008年第S1期51卷 195-202页

作者： LI XiaoJuan,GONG HuiLi,ZHANG Ou,ZHANG WeiGuang & SUN YongHua The key Lab of 3D Information Acquisition and Application,MOE,the key Lab of beijing Resource Envi-ronment and GIS,and College of Resource Environment & Tourism,capital normal university,beijing 100037,china The key Lab of 3D Information Acquisition and Application MOE the Key Lab of Beijing Resource Environment and GIS and College of Resource Environment & Tourism Capital Normal University Beijing China

Using aerial photos and high resolution satellite images of the year of 2004,this paper establishes remote sensing interpretation marks of the Great Wall of Ming Dynasty's damaged levels. Based on field survey and remote sensing survey in 1984,we analyzed present situation and changing characteristics being of the Great Wall of Ming Dynasty in beijing. The results show that about 7.02% of the wall is well-preserved (about 25861 m); 31.5% of the wall is slightly or moderately dam-aged (about 115989 m); 61.5% of the wall is badly damaged (about 226379 m). This paper analyzes the dynamic change of the Great Wall of Ming Dynasty. It shows that the damaged situation of the Great Wall of Ming Dynasty in beijing is serious. From 1984 to 2004,the well-preserved wall is decreased by 33206 m (decreased by 56%); badly damaged wall increased by 51207 m (increased by 67%). Finally,this paper analyzes the influence factors of damaging Great Wall. The conclusion is as follows: The damaged Great Wall is generally near the roads and villages,small slope,and easily arriving land.

关键词： the Great Wall of Ming Dynasty remote sensing interpreting damage dynamic change spatial analysis

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The Villin/Gelsolin/Fragmin Superfamily Proteins in Plants

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Journal of Integrative Plant Biology 2007年第8期49卷 1183-1191页

作者： Hui Su Ting Wang Huaijian Dong Haiyun Ren (key laboratory of Cell Proliferation and Regulation Biology of Ministry of Education and College of Life Sciences beijing normal university beijing 100875 china key laboratory of Cell Proliferation and Regulation Biology of Ministry of Education and College of Life Sciences Beijing Normal University Beijing 100875 China

The villin/gelsolin/fragmin superfamily is a conserved Ca^2＋-dependent family of actin-regulating proteins that is widely present both in mammalian and non-mammalian organisms. They have traditionally been characterized by the same core of three or six tandem gelsolin subdomains. The study in vertebrates and lower eukaryotic cells has revealed that the villin/gelsolin/fragmin superfamily of proteins has versatile functions including severing, capping, nucleating or bundling actin filaments. In plants, encouraging progress has been made in this field of research in recent years. This review will summarize the identified plant homologs of villin/gelsolin/fragmin superfamily, thus providing a basis for reflection on their biochemical activities and functions in plants.

关键词： actin-binding protein actin cytoskeleton Villin/Gelsolin/Fragmin.

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Cu(Ⅱ) Potentiation of Alzheimer Aβ1-40 Cytotoxicity and Transition on its Secondary Structure

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 765-772页

作者： Xue-Ling DAI~1 Ya-Xuan SUN~2 Zhao-Feng JIANG~2* 1 College of Life Science,capital normal university,beijing 100037,china.2 College of Applied Sciences and Humanities,beijing Union university,beijing 100083,china College of Life Science Capital Normal UniversityBeijing 100037 China College of Applied Sciences and Humanities Beijing Union UniversityBeijing 100083 China

Mounting evidence has shown that dyshomeostasis of the redox-active biometals such as Cuand Fe can lead to oxidative stress,which plays a key role in the neuropathology of Alzheimer's disease（AD）.Here we demonstrate that with the formation of Cu（Ⅱ）·Aβ1-40 complexes,copper markedly potentiatesthe neurotoxicity exhibited by β-amyloid peptide （Aβ）.A greater amount of hydrogen peroxide was releasedwhen Cu（Ⅱ）·Aβ1-40 complexes was added to the xanthine oxidase/xanthine system detected by potassiumiodide *** bound to Aβ1-40 was observed by electron paramagnetic resonance（EPR） *** dichroism （CD） studies indicated that copper chelation could cause a structuraltransition of Aβ.The addition of copper to Aβ introduced an increase on β-sheet as well as α-helix,whichmay be responsible for the aggregation of Aβ.We hypothesized that Aβ aggregation induced by copper maybe responsible for local injury in *** interaction between Cu2+and Aβ also provides a possible mechanismfor the enrichment of metal ions in amyloid plaques in the AD brain.

关键词： Alzheimer’s disease Cu(Ⅱ)·Aβ1-40 complex neuron injury Aβ secondary structure

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