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Search Results: 1 - 10 of 754 matches for " Zha Xianfeng "
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Alternative expression of TCRζ related genes in patients with chronic myeloid leukemia
Zha Xianfeng,Yan Xiaojuan,Shen Qi,Zhang Yuping
Journal of Hematology & Oncology , 2012, DOI: 10.1186/1756-8722-5-74
Abstract: A previous study has demonstrated a significant decrease in the TCRζ gene expression level in chronic myeloid leukemia (CML); thus, we further investigated the expression of TCRζ-regulating factors, the distribution of the TCRζ 3' untranslated region (3'-UTR) splice variants, and the expression level and correlation of the alternative splicing factor/splicing factor 2 (ASF/SF-2), FcεRIγ and ZAP-70 genes. TCRζ 3'-UTR splice variants were identified in peripheral blood mononuclear cells (PBMCs) from 14 healthy individuals, 40 patients with CML and 22 patients with CML in complete remission (CML-CR) by RT-PCR. The expression level of the TCRζ, FcεRIγ, ASF/SF-2 and ZAP-70 genes was analyzed by real-time quantitative PCR. While the expression of TCRζ gene in the CML group was significantly lower than that in the healthy individual and CML-CR groups, a significantly higher expression of the FceRIγ and ASF/SF-2 genes was found in the CML group. Two types of splicing forms were detected in all of the healthy individual CML-CR cases: wild type (WT) TCRζ 3'-UTR and alternatively splieced (AS) TCRζ 3'-UTR which have been alternatively splieced in the WT TCRζ 3'-UTR . However, 35% of the CML cases contained only the wild type TCRζ 3'-UTR isoform. Based on the TCRζ 3'-UTR isoform expression characteristic, we divided the patients with CML into two subgroups: the WT+AS- CML group, containing patients that express only the wild type TCRζ 3'-UTR, and the WT+AS+ CML group, which contained patients that expressed two TCRζ 3'-UTR isoforms. A significantly different ASF/SF-2 and FcεRIγ gene expression pattern was found between the WT+AS- and WT+AS+CML groups. We concluded that defective TCRζ expression may be characterized in the WT+AS-and WT+AS+CML subgroups by the different gene expression pattern. The overexpression of ASF/SF2, which alternatively splices the TCRζ 3’-UTR, is thought to participate in feedback regulation. The characteristics of TCRζ 3'-UTR alternative splicing may be a novel immunological marker for the evaluation of the CML immune status.
Evolution of T-cell clonality in a patient with Ph-negative acute lymphocytic leukemia occurring after interferon and imatinib therapy for Ph-positive chronic myeloid leukemia
Liang Wang, Kanger Zhu, Xianfeng Zha, Shaohua Chen, Lijian Yang, Si Chen, Yangqiu Li
Journal of Hematology & Oncology , 2010, DOI: 10.1186/1756-8722-3-14
Abstract: To investigate the dynamic change of clonal proliferation of T cell receptor (TCR) Vα and Vβ subfamilies in one CML patient who developed Ph-negative acute lymphoblastic leukemia (ALL) after interferon and imatinib therapy.The peripheral blood mononuclear cells (PBMC) samples were collected at the 3 time points (diagnosis of Ph-positive chronic phase (CP) CML, developing Ph-negative ALL and post inductive chemotherapy (CT) for Ph-negative ALL, respectively). The CDR3 size of TCR Vα and Vβ repertoire were detected by RT-PCR. The PCR products were further analyzed by genescan to identify T cell clonality.The CML patient who achieved complete cytogenetic remission (CCR) after 5 years of IFN-α therapy suddenly developed Ph-negative ALL 6 months following switch to imatinib therapy. The expression pattern and clonality of TCR Vα/Vβ T cells changed in different disease stages. The restrictive expression of Vα/Vβ subfamilies could be found in all three stages, and partial subfamily of T cells showed clonal proliferation. Additionally, there have been obvious differences in Vα/Vβ subfamily of T cells between the stages of Ph-positive CML-CP and Ph-negative ALL. The Vα10 and Vβ3 T cells evolved from oligoclonality to polyclonality, the Vβ13 T cells changed from bioclonality to polyclonality, when Ph-negative ALL developed.Restrictive usage and clonal proliferation of different Vα/Vβ subfamily T cells between the stages of Ph-positive CP and Ph-negative ALL were detected in one patient. These changes may play a role in Ph- negative leukemogenesis.Chronic myeloid leukemia (CML) is genetically characterized by the presence of the reciprocal translocation t (9; 22) (q34; q11), resulting in a BCR/ABL gene fusion on the derivative chromosome 22 called the Philadelphia chromosome (Ph). Blastic transformation (BT) remains a dire outcome of CML patients with a poor prognosis. Non-random additional chromosome abnormalities accompanied by Philadelphia chromosome can be detected in 60-8
Generation of diffuse large B cell lymphoma-associated antigen-specific Vα6/Vβ13+T cells by TCR gene transfer
Qingsong Yin, Xianfeng Zha, Lijian Yang, Shaohua Chen, Yubing Zhou, Xiuli Wu, Yangqiu Li
Journal of Hematology & Oncology , 2011, DOI: 10.1186/1756-8722-4-2
Abstract: Two different eukaryotic expression plasmids harboring TCR Vα6 and TCR Vβ13 genes specific for DLBCL-associated antigens were constructed and subsequently transferred into human T cells using Nucleofector? technique. The expression of targeted genes in TCR gene-modified cells was detected by real-time PCR, and western blot using TCR Vβ antibody. The specific cytotoxicity of TCR gene-transferred T cells in vitro was estimated using a lactate dehydrogenase (LDH) release assay.Two different eukaryotic expression plasmids harboring TCR Vα6 and TCR Vβ13 genes specific for DLBCL-associated antigens were constructed and subsequently transferred into T cells from healthy donors. Specific anti-DLBCL cytotoxic T lymphocytes (CTL) could be induced by transduction of specific TCR gene to modify healthy T cells. The transgene cassette of TCR Vβ13-IRES-TCR Vα6 was superior to the other in the function of TCR-redirected T cells.Specific anti-DLBCL cytotoxic T lymphocyte (CTL) could be inducted by transduction of specific TCR gene to modify healthy T cells.In the past two decades, fundamental advances in immunology have introduced cellular-based therapies for cancer patients [1,2]. Donor lymphocyte infusion (DLI) has rendered or induced remission in relapsed patients [3-5]. Autologous tumor-infiltrating lymphocytes (TILs) have been found to mediate objective cancer regression [6-8]. In recent years, specific adoptive immunotherapy with tumor-specific cytotoxic T lymphocyte (CTL) has been considered a promising treatment in malignancy, which might eradicate minimal residual disease without increasing toxicity [9,10]. however, the generation of tumor-specific T cells in this mode of immunotherapy is often limiting. The isolation and in vitro expansion of antigen-specific T cell clones remains time-consuming and labor-intensive, such that this treatment is only available to a limited number of patients. To overcome this limitation, another approach has been developed for cancer immuno
An Optical Path Length Modulator for Laser Diode Self-Mixing Interference  [PDF]
Xianfeng Hu
Optics and Photonics Journal (OPJ) , 2017, DOI: 10.4236/opj.2017.71001
Abstract: Transparent liquid flattening or stretching realizes optical path length modulation. A flat thin seal transparent cavity, one flank is an electromagnetic driving membrane and is filled over with transparent liquid. Vibration of the membrane makes the liquid compressing or stretching, changes the liquid layer thickness, i.e. the optical path length of light through the liquid layer. The liquid layer compressed is equivalent to increase membrane tension. The membrane has higher resonant frequency. The cavity diameter 10 mm modulation frequency is about 18 kHz.
New blind estimation method of evoked potentials based on minimum dispersion criterion and fractional lower order statistics  [PDF]
Daifeng Zha
Journal of Biomedical Science and Engineering (JBiSE) , 2008, DOI: 10.4236/jbise.2008.12015
Abstract: Evoked potentials (EPs) have been widely used to quantify neurological system properties. Tra-ditional EP analysis methods are developed under the condition that the background noises in EP are Gaussian distributed. Alpha stable distribution, a generalization of Gaussian, is better for modeling impulsive noises than Gaussian distribution in biomedical signal proc-essing. Conventional blind separation and es-timation method of evoked potentials is based on second order statistics or high order Statis-tics. Conventional blind separation and estima-tion method of evoked potentials is based on second order statistics (SOS). In this paper, we propose a new algorithm based on minimum dispersion criterion and fractional lower order statistics. The simulation experiments show that the proposed new algorithm is more robust than the conventional algorithm.
西昆仑麻扎达坂辉绿岩墙的成因:来自年代学和地球化学证据
Origin of Diabase Dykes in Mazar Area in West Kunlun Orogenic Belt:Evidences from Zircon U-Pb Dating and Geochemistry

查显锋, 高晓峰,李平,计文化
Zha Xianfeng
,Gao Xiaofeng ,Li Ping ,Ji Wenhua

地球科学(中国地质大学学报) , 2018, DOI: 10.3799/dqkx.2018.327
Abstract: 西昆仑造山带显生宙以来经历了原特提斯洋和古特提斯洋两个重要的演化阶段.目前对古特提斯洋构造过程的认识仍然存在较大争议.通过对麻扎达坂辉绿岩墙进行详细的野外地质、岩石学、锆石UPb年代学及岩石地球化学研究,结果表明,辉绿岩锆石U-Pb谐和年龄为287±4.6 Ma,代表了辉绿岩浆的结晶年龄,表明该辉绿岩墙为早二叠世岩浆活动的产物.辉绿岩的SiO2含量为48.29%~50.21%,低Mg#值(0.36~0.39),属亚碱性拉斑系列玄武岩.辉绿岩富集LREE、LILE(如Rb、Ba、Sr),亏损Nb-Ta、P等高场强元素,总体表现出类似岛弧火山岩的地球化学特征.同时,麻扎达坂辉绿岩锆石Hf同位素组成εHf(t)=4.00~13.71,平均值为7.61,TDM1(Hf)=0.76~0.38 Ga)说明其不是来源于类似N-MORB的亏损地幔源区.区域地质研究表明,西昆仑及以北塔里木克拉通在早二叠世处于伸展构造背景,不存在同期的俯冲消减事件,倾向于认为麻扎达坂辉绿岩墙是在造山后伸展背景下,早期俯冲流体交代的岩石圈地幔部分熔融形成的原始岩浆经过一定程度的分异结晶沿区域性断裂侵位形成的,而与塔里木地幔柱不具有地球动力学上的联系.
The West Kunlun orogenic belt underwent the tectonic process of Proto- and Paleo-Tethys Oceans since Phanerozoic. However, there is still much controversy over the evolution of the Paleo-Tethys Ocean. Geochemistry and zircon U-Pb and Hf -isotopic compositions of the diabase dykes in Mazar, West Kunlun are reported in this paper. Zircon U-Pb dating results give an emplacement age of 287±4.6 Ma for the Mazar diabase. These rocks span a SiO2 range of 48.29%-50.21% and Mg# (0.36-0.39), characterized by moderate LREE/HREE fractionation, strong LILEs (such as Rb, Ba, Sr) enrichment and depleted Nb-Ta, P and weakly Eu depletion. They have more radiogenic zircon Hf isotopic compositions εHf(t)=4.00-13.71, average value is 7.61) than N-MORB. In combination with the evolution of regional geology, it is suggested that these melts were derived from partial melting of an enriched lithospheric mantle that underwent early subducted fluid metasomatization. The origin of the Mazar diabase dykes indicates that the post-orogenic extension in West Kunlun, from Late Devonian to Early Permian, may be not related to the Tarim mantle plume
An Analysis of the Benfit on Green Risk in Construction Projects  [PDF]
Xianfeng Zhang, Chuanmin Shuai
Journal of Environmental Protection (JEP) , 2010, DOI: 10.4236/jep.2010.13038
Abstract: The Construction project green risks (CPGRs) refer to those threats to environment, energy sources and material re-sources during the entire life-cycle of a construction project. The emergent green risks in exploiting these resources are of varying concern to all. In this paper, evolutionary game is introduced to make about impacts of strategy choices from interactions among the choices developers, and between the choices developers and EPDs on project green risk. The results show that CPGRs will occur if either developers find that not managing CPGRs has a better payoff than opting for CPGR management, or if monitors impose only mild fines even when they find CPGRs within construction projects of developer’s firms. The study also shows that there is a prohibitively expensive cost incurred by EPDs in monitoring CPGRs. Finally, some strategies are given for EPDs to help them make policies to regulate the strategies of developers.
How “Civic” the Trend Developed in the Histories of the Universities  [PDF]
Xianfeng Wu, Philip Oldfield
Open Journal of Social Sciences (JSS) , 2015, DOI: 10.4236/jss.2015.36003
Abstract:

Historically, the definition of the University is inevitably dynamically changed by the theories, culture and social perspectives of different times. The university in the 21st century has an obvious tendency to much more flexible, integrated and most importantly, civic. This paper firstly clarifies the definition of the university; then the relationships between the university and the city are discussed. Thirdly, the civic university in U.K and U.S are separately reviewed. Lastly, the trend of the university—civic—is summarised and the future work on how to make high density university in 21st century increasingly civic is proposed.

Research on the Construction of Consumption Experience Dimensions for the E-Commerce Offline Store  [PDF]
Xianfeng Wu, Hanmeng Tan
Open Journal of Social Sciences (JSS) , 2019, DOI: 10.4236/jss.2019.73034
Abstract: Under the background of new retail, many E-commerce giants at home and abroad have started to open offline stores, and claimed to incorporate the consumption experience of offline stores into the superior future strategies. Based on the literature review and practical research methods, this paper explores the characteristics of this new E-commerce offline store which involves online and offline consumption experience features, and constructs the consumption experience dimensions belonging to the E-commerce offline store: sensory experience, emotion experience, service experience, convenience experience, interaction experience.
柴北缘西端盐场北山二长花岗岩年代学、 地球化学及其Hf同位素特征
Geochronology, Geochemistry, and Hf Isotope of Yanchangbeishan Adamellite of Lenghu Area in Qinghai

董增产,辜平阳,陈锐明,查显锋,张海迪,
Dong Zengchan''
, Gu Pingyang', Chen Ruiming, Zha Xianfeng'', Zhang Haidi'

地球科学(中国地质大学学报) , 2015, DOI: 10.3799/dqkx.2015.009
Abstract: 盐场北山二长花岗岩位于柴北缘西端青海冷湖地区.岩体高硅(74.98% ~76.92%),富钾(4.44% ~5.93%),贫镁 (0.04%~0.07%)和钙(0.43%~0.69%).里特曼指数介于2.43~2.79属于高钾钙碱性岩石系列,铝饱和指数平均为1.01,属弱 过铝质花岗岩.岩体富集大离子亲石元素(K、Rb、Ba、Pb),亏损高场强元素(Nb、Ta),具岛弧花岗岩地球化学特征.LA-ICP-MS 锆石U-Pb测年结果表明:岩体形成于252±3Ma;锆石Hf同位素初始比值176Hf/177Hf分布于0.282958~0.283032之间,并 具有极高的正εHf(t)值(8.75~14.50),其平均两阶段模式年龄TDM2(Hf)为385Ma,反映岩体源区可能为玄武质下地壳.另外, εHf(t)基本位于亏损地幔演化线附近,指示该玄武质下地壳来源于亏损地幔.结合区域地质背景和岩石地球化学特征,认为盐 场北山二长花岗岩与泥盆纪镁铁-超镁铁岩有关,由于宗务隆裂谷小洋盆的向南俯冲,引发其上覆玄武质新生地壳发生熔融 形成,进而揭示晚二叠世末柴北缘处于火山弧或活动陆缘的构造环境.
The adamellite deve1ops in Yanchangbeishan of Lenghu area in Qinghai, which is1ocated in the west segment of the north margin of Qaidam. The samples have higher SiO2 (74.98%-76.92%) and K20(4.44%-5.93%) contents, but1ower MgO (0.04%-0.07%) and Ca0(0.43%-0.69%) contents. The Rittmann indices of the rock range in2.43-2.79, which shows that it be1ongs to high potassium calc-alkaline series. The alumina saturation average index is1.01, which indicates that the adamellite be1ongs to peraluminous granites. Moreover, the samples are intensively depleted in HFSEs(Nb, Ta) , with enriched LILEs(K,Rb, Ba, Pb) , reflecting the characteristics of island-arc magma. LA-ICP-MS zircon U-Pb dating shows that the formation age of the rock is252士 3 Ma. The zircon Hf isotope analysis reveals that176Hf/177Hf ratios, varying in 0.282 958 to 0.283 032, have high positiveεH1(t) (8.75-14.50) and two-stage Hf mode1 ages(averaged at385 Ma). In the176Hf/177Hf-sHl(t) discrimation diagrams, these zircons are p1otted nearly on the depleted mantle evolutionline. It can be concluded that the rock chielly derived from the new basaltic1ower crust which is originated from depleted mantle. Based on the regiona1 geo1ogica1 background and the geochemica1 characteristics of the mas- ses, we consider that Yanchangbeishan adamellite bears similar characteristics of its primary magma with mafic-ultramafic rocks of De- vonian, which were supposed to be originated from partia1 melting of the young basaltic lower crust related to subduction of Zongwu1ong sma11 oceanic basin from south. Thereby, it reveals that the north margin of Qaidam was in volcanic arc or active continental margin tectonic environment during Permian epoch
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