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| 1 | Spatiotemporal changes in vegetation coverage and its driving factors in the Three-River Headwaters Region during 2000-2011显示文摘The Three-River Headwaters Region(TRHR), which is the source area of the Yangtze River, Yellow River, and Lancang River, is of key importance to the ecological security of China. Because of climate changes and human activities, ecological degradation occurred in this region. Therefore, 'The nature reserve of Three-River Source Regions' was established, and 'The project of ecological protection and construction for the Three-River Headwaters Nature Reserve' was implemented by the Chinese government. This study, based on MODIS-NDVI and climate data, aims to analyze the spatiotemporal changes in vegetation coverage and its driving factors in the TRHR between 2000 and 2011, from three dimensions. Linear regression, Hurst index analysis, and partial correlation analysis were employed. The results showed the following:(1) In the past 12 years(2000–2011), the NDVI of the study area increased, with a linear tendency being 1.2%/10a, of which the Yangtze and Yellow River source regions presented an increasing trend, while the Lancang River source region showed a decreasing trend.(2) Vegetation coverage presented an obvious spatial difference in the TRHR, and the NDVI frequency was featured by a bimodal structure.(3) The area with improved vegetation coverage was larger than the degraded area, being 64.06% and 35.94%, respectively during the study period, and presented an increasing trend in the north and a decreasing trend in the south.(4) The reverse characteristics of vegetation coverage change are significant. In the future, degradation trends will be mainly found in the Yangtze River Basin and to the north of the Yellow River, while areas with improving trends are mainly distributed in the Lancang River Basin.(5) The response of vegetation coverage to precipitation and potential evapotranspiration has a time lag, while there is no such lag in the case of temperature.(6) The increased vegetation coverage is mainly attributed to the warm-wet climate change and the implementation of the ecological protection project. | LIU Xianfeng ZHANG Jinshui ZHU Xiufang PAN Yaozhong LIU Yanxu ZHANG Donghai LIN Zhihui | 2014 | Journal of Geographical Sciences2014，24，2： | 47 |
| 2 | Theoretical analysis and experimental investigation on flexural performance of steel reinforced ultrahigh toughness cementitious composite (RUHTCC) beams显示文摘UHTCC (ultrahigh toughness cementitious composite), which is a kind of ultrahigh toughness cemen- titious composites material, exhibits pseudo strain hardening feature when subjected to tension load, and has enormous ductility and prominent crack dispersal ability. Accordingly, UHTCC can improve mechanical behavior of ordinary concrete structure especially its durability, and has been regarded as historical breakthrough to traditional cementitious materials. In this paper, the study focuses on flexure behavior of steel reinforced beam made of UHTCC. Based on the plane section assumption, along with two equilibrium equations of force and moment, the formulae to calculate the flexural load capability for the reinforced ultrahigh toughness cementitious composite (RUHTCC) beam were developed under the assumption that the compression stress- strain relationship in the UHTCC material is a bilinear model. Following this, the simplified formulae were further evolved by effective rectangle stress distribution approach in order to facilitate design of practical engineering. Two effective parameters introduced in effective rectangle approach were determined. The mathematical expressions to evaluate limited rein- forcement ratio, flexural stiffness as well as ductility index were proposed, too. Last, two series of dif- ferent reinforcement ratios of the RUHTCC beams were tested in four-point flexure loading. For com- parison purposes, ordinary RC (reinforced concrete) beams also were prepared. Both moment curva- ture curves and load mid-span displacement curves were recorded and compared with the theoretical calculations. A good agreement between them was found, which validates the proposed theoretical formulae. For ductility index, a slightly big difference between the experimental values and the calcu- lated ones exists. The experimental results show that, compared to control RC beams, the RUHTCC beam can improve both flexural capacity and ductility index, and the degree of improvement will de- crease with the increase in the reinforcement ratio. Particularly, the results also reveal that lager crack width in control beams can be greatly reduced by formation of tightly-spaced fine cracks in UHTCC, which offers more durable structures. | XU ShiLang ZHANG XiuFang | 2009 | Science China(Technological Sciences)2009，52，4： | 18 |
| 3 | Adipose-derived mesenchymal stem cell transplantation promotes adult neurogenesis in the brains of Alzheimer's disease mice显示文摘In the present study,we transplanted adipose-derived mesenchymal stem cells into the hippocampi of APP/PS1 transgenic Alzheimer’s disease model mice.Immunofluorescence staining revealed that the number of newly generated(BrdU+)cells in the subgranular zone of the dentate gyrus in the hippocampus was significantly higher in Alzheimer’s disease mice after adipose-derived mesenchymal stem cell transplantation,and there was also a significant increase in the number of BrdU+/DCX+neuroblasts in these animals.Adipose-derived mesenchymal stem cell transplantation enhanced neurogenic activity in the subventricular zone as well.Furthermore,adipose-derived mesenchymal stem cell transplantation reduced oxidative stress and alleviated cognitive impairment in the mice.Based on these findings,we propose that adipose-derived mesenchymal stem cell transplantation enhances endogenous neurogenesis in both the subgranular and subventricular zones in APP/PS1 transgenic Alzheimer’s disease mice,thereby facilitating functional recovery. | Yufang Yan Tuo Ma Kai Gong Qiang Ao Xiufang Zhang Yao Gong | 2014 | Neural Regeneration Research2014，9，8： | 16 |
| 4 | Gradual solution heat treatment of AlSiCuMg cast alloys显示文摘The microstmcture characteristics of AlSiCuMg cast alloys were studied with different Cu content and the gradual solution treatment by DSC, SEM, TEM and mechanical method. The melting point of α(Al) + Si decreases and polynary eutectic phases with low melting point form with increase of Cu content. Gradual solution treatment includes two steps:solution treating near the melting point of polynary eutectic phase to take it dissolve first, and then increasing solution temperature to take the remainder copper intermetallics dissolved into o(Al). Grain boundaries melting can be avoided by gradual solution treatment, even the maximum solution temperature is above final solidification point, and the age hardening response increases correspondingly. | WANG Guiqing , BIAN Xiufang ,and ZHANG Junyan1) The Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Jinan 250061, China2) Department of Material Science and Technology, Shandong Architectural Engineering Institute, Jinan 250014, China | 2003 | Rare Metals2003，22，4： | 13 |
| 5 | Milling surface roughness for 7050 aluminum alloy cavity influenced by nozzle position of nanofluid minimum quantity lubrication显示文摘In nanofluid minimum quantity lubrication(NMQL)milling of aviation aluminum alloy,it is the bottleneck problem to adjust the position parameters(target distance,incidence angle,and elevation angle)of the nozzle to improve the surface roughness of milling,which has large and uncontrollable errors.In this paper,the influence law of milling cutter speed,helical angle,and cavity shape on the flow field around the milling cutter was studied,and the optimal nozzle profile parameters were obtained.Using 7050 aluminum alloy as the workpiece material,the milling experiment of the NMQL cavity was conducted by utilizing cottonseed oil-based Al2 O3 nanofluid.Results show that the high velocity of the surrounding air flow field and the strong gas barrier could be attributed to high rotating velocities of the milling cutter.The incidence angle of the nozzle was consistent with the helical angle of the milling cutter,the target distance was appropriate at 25–30 mm,and the elevation angle was suitable at 60°–65°.The range and variance analyses of the signal-to-noise ratio of milling force and roughness were performed,and the chip morphology was observed and analyzed.The results show that the optimal combination of nozzle position parameters was the target distance of 30 mm,the incidence angle of 35°,and the elevation angle of 60°.Among these parameters,target distance had the largest impact on cutting performance with a contribution rate of more than 55%,followed by incidence angle and elevation contribution rate.Analysis by orthogonal experiment revealed that the nozzle position parameters were appropriate,and Ra(0.087 lm)was reduced by 30.4%from the maximum value(0.125 lm).Moreover,Rsm(0.05 mm)was minimum,which was 36%lower than that of the seventh group(Rsm=0.078 mm). | Zhenjing DUAN Changhe LI Yanbin ZHANG Lan DONG Xiufang BAI Min YANG Dongzhou JIA Runze LI Huajun CAO Xuefeng XU | 2021 | Chinese Journal of Aeronautics2021，34，6： | 10 |
| 6 | A Simplified PCR-SSP Method for HLA-A2 Subtype in a Population of Wuhan,China显示文摘HLA-A2 is the most frequent HLA-A allele in all ethnic populations, and an important restriction element for peptide presentation to T cells in infectious disease and cancer. However, the HLA-A2 supertype consisting of up to 75 subtypes, mutation studies and analyses using cytotoxic T lymphocytes suggest the functional relevance of subtype-specific differences in HLA-A2 molecules for peptide binding and T-cell recognition. Therefore, it is necessary for T-cell response study to discriminate the HLA-A2 subtypes and to understand the profile of HLA-A2 allelic distribution in a given population. In this study, we developed a simple, robust approach based on the nested polymerase chain reaction using sequence-specific primers (PCR-SSP) to discriminate 17 HLA-A2 subtypes which cover the most HLA-A2 alleles (> 99% allele frequency) reported in Chinese, using 15 combinations of 19 allelic specific primers. In the first round of PCR, 3 combinations of 5 primers were used to determine whether the tested sample was HLA-A2 positive, meanwhile the subtypes of HLA-A*0209 and HLA-A*0215N were determined for the variant position of these two subtypes is in exon 4 instead of exon 2, 3. Samples of HLA-A2 positive were subtyped in the second round of PCR, using PCR products of the first round as templates. This strategy was applied to test the samples of 78 random HLA-A2 positive individuals for their HLA-A2 subtypes. Those samples were screened for HLA-A2 positive by the first round PCR-SSP from 154 healthy blood donors in Wuhan, China. The subtyping results were verified by using flow cytometric analysis (FCM) with HLA-A2 specific monoclonal antibody BB7.2 and DNA sequencing. The typing results of the samples show 50.7% random individuals in the population carry HLA-A2, HLA-A*0201 ranks the first (allele frequency = 15.5%), followed by A*0207 (5.8%), A*0206 (4.7%), A*0203 (2.6%), A*0210 (0.7%), and these 5 alleles account for 99.0% HLA-A2 subtypes of allele frequency. Our study indicates that the developed typing method is simple and reliable for HLA-A2 subtyping in Chinese, and the profile of allelic distribution of HLA-A2 subtypes is revealed in the population of Wuhan, China. | Bing Liang Lijun Zhu Zhihui Liang Xiufang Weng Xiaoling Lu Cai'e Zhang Hui Li Xiongwen Wu | 2006 | Cellular & Molecular Immunology2006，3，6： | 9 |
| 7 | High-Resolution Genome-wide Association Study Identifies Genomic Regions and Candidate Genes for Important Agronomic Traits in Wheat显示文摘Wheat(Triticum aestivum)is a major staple food crop worldwide.Genetic dissection of important agronomic traits is essential for continuous improvement of wheat yield to meet the demand of the world's growing population.We conducted a large-scale genome-wide association study(GWAS)using a panel of 768 wheat cultivars that were genotyped with 327609 single-nucleotide polymorphisms generated by genotyping-by-sequencing and detected 395 quantitative trait loci(QTLs)for 12 traits under 7 environments.Among them,273 QTLs were delimited to≤1.0-Mb intervals and 7 of them are either known genes(Rht-D,Vrn-B1,and Vrn-D1)that have been cloned or known QTLs(TaGA2ox8,APO1,TaSus1-7B,and Rht12)that were previously mapped.Eight putative candidate genes were identified for three QTLs that enhance spike seed setting and grain size using gene expression data and were validated in three bi-parental populations.Protein sequence analysis identified 33 putative wheat orthologs that have high identity with rice genes in QTLs affecting similar traits.Large r^2 values for additive effects observed among the QTLs for most traits indicated that the phenotypes of these identified QTLs were highly predictable.Results from this study demonstrated that significantly increasing GWAS population size and marker density greatly improves detection and identification of candidate genes underlying a QTL,solidifying the foundation for large-scale QTL fine mapping,candidate gene validation,and developing functional markers for genomics-based breeding in wheat. | Yunlong Pang Chunxia Liu Danfeng Wang Paul St.Amand Amy Bernardo Wenhui Li Fang He Linzhi Li Liming Wang Xiufang Yuan Lei Dong Yu Su Huirui Zhang Meng Zhao Yunlong Liangi Hongze Jia Xitong Shen Yue Lu Hongming Jiang Yuye Wu Anfei Li Honggang Wang Lingrang Kong Guihua Bai Shubing Liu | 2020 | Molecular Plant2020，13，9： | 8 |
| 8 | Influence of surface modification of SrFe12O19 particles with oleic acid on magnetic microsphere preparation显示文摘Oleic acid was used as surface modification agent to improve the hydrophobicity of magnetic strontium hexaferrite particles.The structure and properties of treated magnetic particles were characterized by scanning electronic microscopy(SEM),Fourier transform infrared spectra(FTIR),powder X-ray diffraction(XRD) and magnetic property measurement system(MPMS).The results show that oleic acid is chemically enwrapped on the surface of SrFe12O19 particles.Magnetic particles modified by oleic acid are highly dispersible and strongly responsive to magnetism but with slight decrease in saturated magnetization.The affinity between magnetic particles and monomers is improved by surface modification,resulting in increased particle incorporation in magnetic polymeric microspheres.The surface modification mechanism of magnetic particles by oleic acid is addressed in this work. | Sifang Kong Peipei Zhang Xiufang Wen Pihui Pi Jiang Cheng Zhuoru Yang Jing Hai | 2008 | Particuology2008，6，3： | 7 |
| 9 | Magnetically Driven Superhydrophobic Polyurethane Sponge for High Efficiency Oil/Water Mixtures Separation显示文摘Magnetically driven super-hydrophobic materials were prepared by Fe3O4 nanoparticles and stearic acid,which were deposited on the surface of polyurethane sponges.The presence of the Fe3O4 nanoparticles makes the sponge have the magnetic,and the micro-nano hierarchical structure and hydrophobic functional groups lead to the sponge have excellent superhydrophobicity.The as-prepared sponge exhibited excellent absorption capacities for various oils and organic solvents ranging from 23.8 times to 86.7 times of its own weight.Moreover,the oil separation capacities still keep a high value after 50 cycles of squeezing the saturated absorbed as-prepared sponge.All of these satisfactory properties make the as-prepared sponge as a candidate of ideal absorbents for oily industrial wastewater and oil spills in oceans. | Xuemei Zhang Feng Fu Xiaoming Gao Xiufang Hou | 2019 | Journal of Bionic Engineering2019，16，1： | 6 |
| 10 | Amyloid beta-peptide worsens cognitive impairment following cerebral ischemia-reperfusion injury显示文摘Amyloid β-peptide,a major component of senile plaques in Alzheimer’s disease,has been implicated in neuronal cell death and cognitive impairment.Recently,studies have shown that the pathogenesis of cerebral ischemia is closely linked with Alzheimer’s disease.In this study,a rat model of global cerebral ischemia-reperfusion injury was established via occlusion of four arteries;meanwhile,fibrillar amyloidβ-peptide was injected into the rat lateral ventricle.The Morris water maze test and histological staining revealed that administration of amyloidβ-peptide could further aggravate impairments to learning and memory and neuronal cell death in the hippocampus of rats subjected to cerebral ischemia-reperfusion injury.Western blot showed that phosphorylation of tau protein and the activity of glycogen synthase kinase 3βwere significantly stronger in cerebral ischemia-reperfusion injury rats subjected to amyloid β-peptide administration than those undergoing cerebral ischemia-reperfusion or amyloidβ-peptide administration alone.Conversely,the activity of protein phosphatase 2A was remarkably reduced in rats with cerebral ischemia-reperfusion injury following amyloidβ-peptide administration.These findings suggest that amyloidβ-peptide can potentiate tau phosphorylation induced by cerebral ischemia-reperfusion and thereby aggravate cognitive impairment. | Bo Song Qiang Ao Ying Niu Qin Shen Huancong Zuo Xiufang Zhang Yandao Gong | 2013 | Neural Regeneration Research2013，8，26： | 5 |
| 11 | 基于桐油热处理的竹材理化性质研究显示文摘寻求绿色、可持续发展的改性方法来生产耐用竹材制品,是目前竹产业面临的挑战。本文将桐油热处理技术应用于竹材改性,探讨了桐油热处理过程中桐油在竹材中的渗透行为和分布,研究了桐油与热处理的协同作用对竹材化学性质、物理性质、力学性质的影响以及相互作用机制。结果表明,桐油热处理不仅可以增强竹材的疏水性能和尺寸稳定性,改善竹材的防霉性能,而且竹材可以保持其良好的力学性能。与未处理竹材相比,200℃桐油热处理后竹材的饱水膨胀率从3.17%下降至2.42%,200℃桐油热处理后竹材径切面的接触角在300 s时仍可保持在100°以上。桐油热处理后竹材性能的改善归因于竹材化学成分的变化、纤维结晶度的增加、竹材外表面和细胞腔内表面油膜的形成。因此,桐油热处技术在竹材工业改性中具有良好的发展前景。 | 费本华 唐彤 Tong Tang Bo Zhang Xianmiao Liu Wenbo Wang Xiufang Chen Benhua Fei | 2019 | 世界竹藤通讯2019，17，5： | 5 |
| 12 | A new threshold of uncovering the nature of glass transition:The slow β relaxation in glassy states显示文摘The glass transition involves more than one dynamic relaxation mechanisms in supercooled liquids,such as α relaxation,slow β relaxation and fast β relaxation and so on.For the traditional theoretical system,α relaxation is believed mainly responsible for the nature of the glass transition as the beginning of the phenomenon.This idea,however,has been open to a big challenge since recent studies have indicated that slow β relaxation closely relates to α relaxation.Slow β relaxation determines the characteristics of α relaxation and is the precursor and the more microscopic base of glass transition behavior.In order to illuminate the significance of slow β relaxation in the fields of the glass transition and the structure of supercooled liquids,the accomplished progress is summarized from different aspects such as on the correlation between α relaxation and slow β relaxation,on the manner of α-slow β relaxation merging,on the energy landscape,on the excess wing and on the thermodynamically phenomenological models.The tendency of investigation in slow β relaxation is also evaluated. | HU LiNa ZHANG ChunZhi YUE YuanZheng BIAN XiuFang | 2010 | Chinese Science Bulletin2010，55，6： | 4 |
| 13 | Preparation and characterization of porous titania-grafted poly(styrene-divinylbenzene)/maleic anhydride nanocomposite microspheres显示文摘Mesoporous titania-grafted poly(styrene-divinylbenzene)/maleic anhydride [P(St-DVB)/MA] nanocomposite microspheres were prepared by an open ring reaction method.The titania nanoparticles were first modified by attachment of amino groups to their surface to prevent particle aggregation,and to allow the nanoparticles to covalently bond the polymer microspheres,the surface of which was modified by attachment of MA functional groups to enable the polymer to retain their porous structures and to react with the amino groups on the surface of the titania particles.The porous nanocomposite microspheres were detected by FTIR,SEM,TEM,XRD and UV-Vis spectrophotometry.The results indicated that the nanocomposite microspheres were composed of nanosized titania uniformly distributed on the surface,and exhibited better UV absorbing property than pure polymer microspheres or unmodified titania.Furthermore,compared with pure porous polymer microspheres,the nanocomposite microspheres showed more efficient UV protection and slow release of Parsol-1789(a photo-reactive and cosmetic agent) held inside the porous network of the microspheres. | Li Sen Wang Kuan Zhang ZhiRen Song ChunLian Cheng Jiang Yang ZhuoRu Wen XiuFang Pi PiHui | 2010 | Science China Chemistry2010，53，3： | 3 |
| 14 | Vacuum carburization of 12Cr2Ni4A low carbon alloy steel with lanthanum and cerium ion implantation显示文摘As bearing parts, 12 Cr2 Ni4 A is expected to have high hardness and excellent fatigue strength, so carburizing is employed to improve the inherit properties of 12 Cr2 Ni4 A. However, the traditional carburizing is limited by poor microstructure distribution and low rate of carburizing. The rare earth ion implantation is known to help improving the properties of tribology, corrosion resistance and oxidation resistance of metal. In this article, the RE implantation is employed to assist the carburizing. Lanthanum and cerium ion implantations are initially used to assist 12 Cr2 Ni4 A low pressure vacuum carburization.The microstructure, content of retained austenite, hardness, thickness of layer and carbon diffusion were analyzed by optical microscopy(OM), scanning electron microscopy(SEM), X-ray diffraction(XRD) and Rockwell/Vickers hardness tester, respectively. It was shown that lanthanum and cerium implantations can improve structure of the vacuum carburizing layer, and enhance the uniformity of carbon element distribution on the carburized surface. Meanwhile the RE implantation plays a positive role in promoting the surface hardness and carburized rate. The lanthanum element has more significant effect on surface hardness and content of retained austenite than cerium element. The surface hardness of lanthanum element implanted layer was 62.9 HRC with 9.6% content of retained austenite, while the carburizing rate of cerium implanted layer increased by 12.4%. | Meiling Dong Xiufang Cui Yuhui Zhang Guo Jin Caiwen Yue Xin Zhao Zhaobing Cai Binshi Xu | 2017 | Journal of Rare Earths2017，35，11： | 3 |
| 15 | ESTIMATION OF DOPPLER CENTROID FREQUENCY IN SPACEBORNE SCANSAR显示文摘Doppler centroid frequency is an essential parameter in the imaging processing of the Scanning mode Synthetic Aperture Radar (ScanSAR). Inaccurate Doppler centroid frequency will result in ghost images in imaging result. In this letter, the principle and algorithms of Doppler centroid frequency estimation are introduced. Then the echo data of ScanSAR system is analyzed. Based on the algorithms of energy balancing and correlation Doppler estimator in the estimation of Doppler centroid frequency in strip mode SAR, an improved method for Doppler centroid frequency estimation in ScanSAR is proposed. The method has improved the accuracy of Doppler centroid frequency estimation in ScanSAR by zero padding between burst data. Finally, the proposed method is validated with the processing of ENVIronment SATellite Advanced Synthetic Aperture Radar (ENVISAT ASAR) wide swath raw data. | Zou Xiufang Zhang Qunying | 2008 | Journal of Electronics(China)2008，25，6： | 3 |
| 16 | HPLC-DAD data coupled with second-order calibration method applied to food analysis: Simultaneous determination of six benzoylurea insecticides in various fruit samples by selecting time region of chromatogram显示文摘This work presents a novel application of second-order calibration based on self-weighted alternating trilinear decomposition(SWATLD)algorithm for analyzing the HPLC-DAD data.The proposed method makes it possible to simultaneously determine teflubenzuron,hexaflumuron,flufenoxuron,chlorfluazuron,diflubenzuron and benzoylurea in different fruit samples,i.e.pear,apple and banana,in the selected time region of chromatogram.The concentration,elution time and spectral information of these benzoylurea insecticides are selectively extracted from complex matrices even in the presence of unknown interferences.The root-mean-square error of prediction(RMSEP)and figures of merit,including sensitivity(SEN),selectivity(SEL)and limit of detection(LOD)are employed to access the performance of the method.The LODs obtained for these insecticides are within the range 0.017–0.26 ppm in pears,0.039–0.33 ppm in apples,0.041–0.44 ppm in bananas,respectively.Such a chemometrics-based protocol holds great potential to be extended as a promising alternative for more practical applications in food safety and quality monitoring. | QING XiangDong WU HaiLong NIE ChongChong LI Yong YAN XiuFang ZHANG XiHua YIN XiaoLi YU RuQin | 2013 | Science China Chemistry2013，56，11： | 2 |
| 17 | Winter wheat area estimation from MODIS-EVI time series data using the Crop Proportion Phenology Index显示文摘 | Yaozhong Pan Le Li Jinshui Zhang Shunlin Liang Xiufang Zhu Damien Sulla-Menashe | 2011 | Remote Sensing of Environment2011，，： | 2 |
| 18 | Functional characterization of SOX2 as an anticancer target显示文摘SOX2 is a well-characterized pluripotent factor that is essential for stem cell self-renewal,reprogramming,and homeostasis.The cellular levels of SOX2 are precisely regulated by a complicated network at the levels of transcription,post-transcription,and posttranslation.In many types of human cancer,SOX2 is dysregulated due to gene amplification and protein overexpression.SOX2 overexpression is associated with poor survival of cancer patients.Mechanistically,SOX2 promotes proliferation,survival,invasion/metastasis,cancer stemness,and drug resistance.SOX2 is,therefore,an attractive anticancer target.However,little progress has been made in the efforts to discover SOX2 inhibitors,largely due to undruggable nature of SOX2 as a transcription factor.In this review,we first briefly introduced SOX2 as a transcription factor,its domain structure,normal physiological functions,and its involvement in human cancers.We next discussed its role in embryonic development and stem cell-renewal.We then mainly focused on three aspects of SOX2:(a)the regulatory mechanisms of SOX2,including how SOX2 level is regulated,and how SOX2 cross-talks with multiple signaling pathways to control growth and survival;(b)the role of SOX2 in tumorigenesis and drug resistance;and(c)current drug discovery efforts on targeting SOX2,and the future perspectives to discover specific SOX2 inhibitors for effective cancer therapy. | Shizhen Zhang Xiufang Xiong Yi Sun | 2020 | Signal Transduction and Targeted Therapy2020，5，1： | 2 |
| 19 | Gelation behavior of Antheraea pernyi silk fibroin显示文摘The sol-gel transition behavior of Antherae pernyi silk fibroin(Ap-SF) has not been systematically investigated.In this work,the influence of environmental temperature,pH,the concentration of Ap-SF,K+ and Ca2+ on the gelation time,and the structural changes of Ap-SF in sol-gel transformation were studied.The results indicated that the gelation time of the Ap-SF aqueous solution decreased with the increase of the Ap-SF concentration and environmental temperature.The sol-gel transformation of Ap-SF was much more rapid than that of Bombyx mori silk fibroin under the same conditions.The Ap-SF was sensitive to changes in the concentration of Ca2+ and K+.Upon gelation,the random coil structure of the Ap-SF was significantly transformed into the β-sheet structure. | YAN ShuQin,ZHAO ChunXia,WU XiuFang,ZHANG Qiang & LI MingZhong National Engineering Laboratory for Modern Silk College of Textile and Clothing Engineering,Soochow University,Suzhou 215123,China | 2010 | Science China Chemistry2010，53，3： | 2 |
| 20 | In vitro biocompatibility of three chitosan/polycation composite materials for nerve regeneration显示文摘BACKGROUND:It has been reported that chitosan nerve conduits could support axon elongation and improve relevant function during in vivo nerve regeneration. OBJECTIVE: To investigate in vitro biocompatibility of three novel, chitosan/polycation composite materials for nerve regeneration in cultured mouse Schwann cells and PC12 cells. DESIGN, TIME AND SETTING: The observational, control experiments for nerve tissue engineering were performed at the Department of Biological Sciences and Biotechnology of Tsinghua University from August 2007 to January 2008. MATERIALS: Mouse Schwann cells were isolated from the sciatic nerve of 5–7-day-old BALB/C mice. PC12 cells were purchased from the American Type Culture Collection (ATCC, USA). Chitosan was purchased from Tsingdao Haisheng Co., China. Poly-L-lysine hydrochloride (PLL), polyethyleneimine (PEI) poly-L-ornithine hydrobromide (POR), and S-100 antibody was purchased from Sigma Chemical Co., USA. Cell Counting Kit-8 (CCK-8) was purchased from Dojindo Chemical Co., Japan. METHODS: Three chitosan/polycation composite materials for nerve regeneration (PLL-0.25, PEI-0.25, and POR-0.25) were produced by blending chitosan with 0.25% (w/w) poly-L-lysine, polyethyleneimine, and poly-L-ornithine. Pure chitosan was utilized as the control. After 3 days of culture, the morphology of mouse Schwann and PC12 cells cultured on all substrates was observed with an inverted phase contrast microscope. Mouse Schwann cells were stained by immunofluorescence labeling S-100 protein and nuclei, followed by identification with a confocal laser-scanning microscope. The amount of proliferating mouse Schwann and PC12 cells was determined by CCK-8 after 1, 3, and 5 days in culture. The level of PC12 cell differentiation on all substrates was assessed by measuring neurite length at 1, 3, and 5 days after seeding. MAIN OUTCOME MEASURES: Morphology and amount of proliferation of mouse Schwann cells and PC12 cells cultured on chitosan and three polycation-modified materials, as well as amount of differentiation in PC12 cells on these substrates. RESULTS: (1) Morphology of mouse Schwann cells and PC12 cells on all substrates: after 3 days in culture on three different chitosan/polycation composite substrates, Schwann cells were connected to each other and exhibited greater proliferation, compared to the chitosan control. In particular, on PLL-0.25 and POR-0.25 substrates, some cells congregated and nearly reached confluence. The PC12 cells on chitosan substrate, after 3 days in culture, maintained a round shape; few exhibited a bipolar shape and began to form neurite extensions. However, on PLL-0.25 and POR-0.25 substrates, most PC12 cells displayed a bipolar shape with obvious neurite outgrowth, and almost grew as an adherent, spreading monolayer. (2) Proliferation of mouse Schwann cells and PC12 cells on all substrates: on the first day, Schwann cell proliferation on the three composite substrates was significantly greater than the cells on chitosan control (P < 0.01). After 3 and 5 days in culture, PLL-0.25 and POR-0.25 substrates resulted in greater cell proliferation when compared to pure chitosan (P < 0.01). On the third and fifth day in culture PC12 cell proliferation on PLL-0.25 and POR-0.25 was significantly greater than on chitosan substrate (P < 0.01). (3) Differentiation of PC12 cells on all substrates: at all time points, the average neurite length of cells cultured on composite materials was significantly longer than on chitosan control (P < 0.05-0.01). Cells on PLL-0.25 exhibited the longest average neurite length at days 3 and 5. CONCLUSION: Mouse Schwann cells and PC12 cells exhibit in vitro biocompatibility with poly-L-lysine-and poly-L-ornithine-modified substrates, which indicates that these substrates could serve as suitable substrates for peripheral nerve regeneration. | Zhenhuan Zheng Yujun Wei Gan Wang Yandao Gong Xiufang Zhang | 2008 | Neural Regeneration Research2008，3，8： | 2 |
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