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拟南芥Alpha-dioxygenase1的原核表达、纯化及活性的检测 被引量:3
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作者 张小梅 韩念法 +3 位作者 张美祥 李广录 范三红 郭蔼光 《华北农学报》 CSCD 北大核心 2008年第3期9-12,共4页
从经水杨酸处理的拟南芥开花期植株中获得cDNA,扩增得到Alpha-dioxygenase 1(DOX1)基因,进行原核表达、纯化和生物活性检测。利用原核表达载体pMAL-c4x在T7 Express CompetentE.coli和BL21(DE3)-RIPL codon+菌株中表达DOX1,经Amylose Re... 从经水杨酸处理的拟南芥开花期植株中获得cDNA,扩增得到Alpha-dioxygenase 1(DOX1)基因,进行原核表达、纯化和生物活性检测。利用原核表达载体pMAL-c4x在T7 Express CompetentE.coli和BL21(DE3)-RIPL codon+菌株中表达DOX1,经Amylose Resin亲和层析柱纯化。SDS-PAGE结果表明,重组融合蛋白在BL21(DE3)-RIPL codon+中的表达通过灰度值比较分析以可溶性为主,表达率约3.7%,纯化的DOX1纯度可达45%。愈创木酚法表明,可溶性重组蛋白不具有过氧化物酶活性;2,4-DNP法测试表明可溶性重组蛋白具有脂肪酸双加氧酶活性。 展开更多
关键词 alpha—dioxygenase 1 重组表达 2 4-DNP 亲和纯化 活性
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产气荚膜梭菌Alpha毒素突变体的表达及单克隆抗体制备
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作者 韩凤烨 刘莹 +7 位作者 潘晨帆 张乾义 陈小云 朱真 印春生 温永俊 王凤雪 杜吉革 《中国畜牧兽医》 北大核心 2025年第1期442-450,共9页
[目的]获得产气荚膜梭菌Alpha毒素(Clostridium perfringens alpha-toxin, CPA)的重组突变体,评价其毒力和抗原性,进而制备针对CPA的单克隆抗体,并评价单克隆抗体特性。[方法]通过人工合成含6个氨基酸突变(第56和130位的天冬氨酸突变为... [目的]获得产气荚膜梭菌Alpha毒素(Clostridium perfringens alpha-toxin, CPA)的重组突变体,评价其毒力和抗原性,进而制备针对CPA的单克隆抗体,并评价单克隆抗体特性。[方法]通过人工合成含6个氨基酸突变(第56和130位的天冬氨酸突变为甘氨酸、第275、307和331位的酪氨酸突变为苯丙氨酸、第336位的天冬氨酸突变为天冬酰胺)的CPA基因片段,并将其克隆至pET-30a(+)载体,转化大肠杆菌BL21(DE3)感受态细胞进行诱导表达与纯化,获得重组蛋白rCPA_(m6),并检测其毒力与免疫原性。将rCPA_(m6)作为包被抗原建立CPA抗体的间接ELISA检测方法,并用灭活的天然CPA作为免疫原按照常规方法免疫BALB/c小鼠,制备单克隆抗体,对其功能进行鉴定。[结果]重组蛋白rCPA_(m6)在大肠杆菌BL21(DE3)感受态中能够以可溶性和包涵体两种形式表达。毒力测定结果显示,100μg/只rCPA_(m6)攻毒后,小鼠全部存活。免疫原性分析结果显示,1×最小致死量(MLD)的天然CPA攻毒后,对照组小鼠全部死亡,10和20μg/只rCPA_(m6)免疫组小鼠存活率为100%。利用rCPA_(m6)成功建立了CPA抗体的间接ELISA检测方法,并筛选获得4株分泌抗CPA的单克隆抗体杂交瘤细胞株,分别命名为6E3、6B8、10A11、13D10,且4种细胞上清抗体效价均≥1∶3 200,其中单克隆抗体6B8细胞上清能中和天然CPA,且能与rCPA_(m6)发生反应。[结论]试验成功获得具有良好的安全性和免疫原性的重组蛋白rCPA_(m6),制备的CPA单克隆抗体6B8具有一定的中和活性及较高的特异性和敏感性。研究结果为CPA亚单位疫苗的研制提供了候选抗原,同时为CPA中毒症的治疗以及抗原/抗体检测方法的建立提供了物质基础。 展开更多
关键词 产气荚膜梭菌alpha毒素(CPA) 突变体 原核表达 单克隆抗体
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Alpha-synuclein in mitochondrial dysfunction:opportunities or obstacles
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作者 Shermali Gunawardena 《Neural Regeneration Research》 SCIE CAS 2025年第1期197-198,共2页
Recent work suggests a link betweenα-synuclein(α-syn)and mitochondrial dysfunction;however,the mechanisms of howα-syn influences mitochondrial function are still unclear.Most notably,whetherα-syn plays a direct ro... Recent work suggests a link betweenα-synuclein(α-syn)and mitochondrial dysfunction;however,the mechanisms of howα-syn influences mitochondrial function are still unclear.Most notably,whetherα-syn plays a direct role during mitochondrial function and/or whether diseasedα-syn-mediated mitochondrial dysfunction is a potential modifiable risk factor in Parkinson’s disease(PD)is unknown.To date,mutations in more than eight genes cause familial PD(fPD)and have functions in diverse pathways including synaptic homeostasis,mitochondria maintenance,autophagy/lysosome,and ubiquitin-proteasome pathways. 展开更多
关键词 DYSFUNCTION HOMEOSTASIS alpha
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Acute Inflammatory Pain Induces Sex-different Brain Alpha Activity in Anesthetized Rats Through Optically Pumped Magnetometer Magnetoencephalography
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作者 MIAO Meng-Meng REN Yu-Xuan +5 位作者 WU Wen-Wei ZHANG Yu PAN Chen LIN Xiang-Hong LIN Hui-Dan CHEN Xiao-Wei 《生物化学与生物物理进展》 北大核心 2025年第1期244-257,共14页
Objective Magnetoencephalography(MEG),a non-invasive neuroimaging technique,meticulously captures the magnetic fields emanating from brain electrical activity.Compared with MEG based on superconducting quantum interfe... Objective Magnetoencephalography(MEG),a non-invasive neuroimaging technique,meticulously captures the magnetic fields emanating from brain electrical activity.Compared with MEG based on superconducting quantum interference devices(SQUID),MEG based on optically pump magnetometer(OPM)has the advantages of higher sensitivity,better spatial resolution and lower cost.However,most of the current studies are clinical studies,and there is a lack of animal studies on MEG based on OPM technology.Pain,a multifaceted sensory and emotional phenomenon,induces intricate alterations in brain activity,exhibiting notable sex differences.Despite clinical revelations of pain-related neuronal activity through MEG,specific properties remain elusive,and comprehensive laboratory studies on pain-associated brain activity alterations are lacking.The aim of this study was to investigate the effects of inflammatory pain(induced by Complete Freund’s Adjuvant(CFA))on brain activity in a rat model using the MEG technique,to analysis changes in brain activity during pain perception,and to explore sex differences in pain-related MEG signaling.Methods This study utilized adult male and female Sprague-Dawley rats.Inflammatory pain was induced via intraplantar injection of CFA(100μl,50%in saline)in the left hind paw,with control groups receiving saline.Pain behavior was assessed using von Frey filaments at baseline and 1 h post-injection.For MEG recording,anesthetized rats had an OPM positioned on their head within a magnetic shield,undergoing two 15-minute sessions:a 5-minute baseline followed by a 10-minute mechanical stimulation phase.Data analysis included artifact removal and time-frequency analysis of spontaneous brain activity using accumulated spectrograms,generating spectrograms focused on the 4-30 Hz frequency range.Results MEG recordings in anesthetized rats during resting states and hind paw mechanical stimulation were compared,before and after saline/CFA injections.Mechanical stimulation elevated alpha activity in both male and female rats pre-and post-saline/CFA injections.Saline/CFA injections augmented average power in both sexes compared to pre-injection states.Remarkably,female rats exhibited higher average spectral power 1 h after CFA injection than after saline injection during resting states.Furthermore,despite comparable pain thresholds measured by classical pain behavioral tests post-CFA treatment,female rats displayed higher average power than males in the resting state after CFA injection.Conclusion These results imply an enhanced perception of inflammatory pain in female rats compared to their male counterparts.Our study exhibits sex differences in alpha activities following CFA injection,highlighting heightened brain alpha activity in female rats during acute inflammatory pain in the resting state.Our study provides a method for OPM-based MEG recordings to be used to study brain activity in anaesthetized animals.In addition,the findings of this study contribute to a deeper understanding of pain-related neural activity and pain sex differences. 展开更多
关键词 MAGNETOENCEPHALOGRAPHY PAIN sex differences alpha activity INFLAMMATION
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A novel method for simultaneous measurement of^(222)Rn and^(220)Rn progeny concentrations measured by an alpha spectrometer
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作者 Zhong-Kai Fan Jia-Le Sun +5 位作者 Hao-Xuan Li Xiang-Ming Cai Hui Yang Shou-Kang Qiu Yan-Liang Tan Jian Shan 《Nuclear Science and Techniques》 2025年第1期127-139,共13页
The accumulation of^(222)Rn and^(220)Rn progeny in poorly ventilated environments poses the risk of natural radiation exposure to the public.A previous study indicated that satisfactory results in determining the^(222... The accumulation of^(222)Rn and^(220)Rn progeny in poorly ventilated environments poses the risk of natural radiation exposure to the public.A previous study indicated that satisfactory results in determining the^(222)Rn and^(220)Rn progeny concentrations by measuring the total alpha counts at five time intervals within 560 min should be expected only in the case of high progeny concentrations in air.To complete the measurement within a relatively short period and adapt it for simultaneous measurements at comparatively lower^(222)Rn and^(220)Rn progeny concentrations,a novel mathematical model was proposed based on the radioactive decay law.This model employs a nonlinear fitting method to distinguish nuclides with overlapping spectra by utilizing the alpha particle counts of non-overlapping spectra within consecutive measurement cycles to obtain the concentrations of^(222)Rn and^(220)Rn progeny in air.Several verification experiments were conducted using an alpha spectrometer.The experimental results demonstrate that the concentrations of^(222)Rn and^(220)Rn progeny calculated by the new method align more closely with the actual circumstances than those calculated by the total count method,and their relative uncertainties are all within±16%.Furthermore,the measurement time was reduced to 90 min,representing an acceleration of 84%.The improved capability of the new method in distinguishing alpha particles with similar energies emitted from ^(218)Po and^(212)Bi,both approximately 6 MeV,contributed to realizing more accurate results.The proposed method has the potential advantage of measuring relatively low concentrations of^(222)Rn and^(220)Rn progeny in air more quickly via air filtration. 展开更多
关键词 ^(222)Rn ^(220)Rn Progeny concentration Nonlinear fitting method alpha spectrometer
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三角梅甜菜色素代谢酶4,5-DOPA-dioxygenase基因的分离和表达 被引量:4
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作者 徐夙侠 林春松 +2 位作者 黄青云 曾碧玉 林富聪 《热带作物学报》 CSCD 北大核心 2013年第11期2214-2221,共8页
甜菜色素在自然界中与花青素排斥分布,主要在石竹目(Caryophyllales)的9个科的植物中合成。虽然甜菜色素的生物合成已经有很多猜测,酶催化的生物合成关键步骤仍然缺少足够的实验数据支持。本研究首先从三角梅属的3个种(B.spectabilis‘S... 甜菜色素在自然界中与花青素排斥分布,主要在石竹目(Caryophyllales)的9个科的植物中合成。虽然甜菜色素的生物合成已经有很多猜测,酶催化的生物合成关键步骤仍然缺少足够的实验数据支持。本研究首先从三角梅属的3个种(B.spectabilis‘Splendens’,B.buttiana‘Mahara’,B.pruviana‘Thimma’)的苞片中分离了甜菜色素合成途径末端的关键酶4,5-DOPA-dioxygenase完整的cDNA,大小分别为902、899、899 bp,分别编码298、297、297个氨基酸,并对这3个同源基因与已经报道的来自B.glabra的该基因进行比较。推测的分子量分别为33 758、33 076、33 233 u,等电点(pI)分别是5.62、5.54和5.94。对分属于4个种(B.spectabilis‘Splendens’,B.buttiana‘Mahara’,B.glabra‘Alba’,B.pruviana‘Thimma’)花的4,5-DOPAdioxygenase的Real-time分析结果表明,该基因在4个种的花中,种间变化较大,总体趋势是开花早期该基因的表达较弱,盛花期表达迅速增强,后期又呈现下降。其中,在红色的B.buttiana‘Mahara’中,该基因的表达最强,在白色的B.glabra‘Alba’中表达最弱。这些结果表明,该基因的表达与花的颜色鲜艳程度直接相关。 展开更多
关键词 三角梅 4 5-DOPA-dioxygenase表达
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Cloning and Functional Characterisation of Carotenoid Cleavage Dioxygenase 4 from Wolfberry 被引量:4
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作者 Xiaowei Tian Jing Ji +3 位作者 Gang Wang Chao Jin Cuicui Jia Zhaodi Li 《Transactions of Tianjin University》 EI CAS 2017年第1期62-69,共8页
Carotenoid cleavage dioxygenases (CCDs) are a class of enzymes in plants involved in the biosynthesis of apocarotenoids, such as phytohormones, flavour compounds, and other compounds with yet unknown functions. To dat... Carotenoid cleavage dioxygenases (CCDs) are a class of enzymes in plants involved in the biosynthesis of apocarotenoids, such as phytohormones, flavour compounds, and other compounds with yet unknown functions. To date, several CCDs have been functionally characterised in plants, but little is known about the CCD4 members. A carotenoid cleavage dioxygenase 4 gene (LcCCD4) was isolated from the leaves of wolfberry (Lycium chinense) to gain insight into its biological function. Multiple sequence alignment and phylogenetic analyses showed that the deduced amino acid sequence of LcCCD4 shares high homology with that of CCD4 proteins from other plants. Expression analysis using semi-quantitative polymerase chain reaction revealed that LcCCD4 was strongly expressed in leaves and flowers and that the expression level was in accordance with β-carotene concentration. LcCCD4 transcripts in fruits tended to decrease as carotenoids accumulated. Recombinant expression of LcCCD4 cleaved β-carotene to produce β-ionone in in vivo assays. These results show that LcCCD4 is a CCD gene that may be involved in producing aromatic apocarotenoids in leaves and flowers, whereas it may be involved in controlling carotenoid accumulation in fruits. © 2016, Tianjin University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 BIOCHEMISTRY FRUITS Genes Plants (botany) Polymerase chain reaction
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Indoleamine-2,3-dioxygenase 1/cyclooxygenase 2 expression prediction for adverse prognosis in colorectal cancer 被引量:5
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作者 Wen-Juan Ma Xing Wang +4 位作者 Wen-Ting Yan Zhong-Guo Zhou Zhi-Zhong Pan Gong Chen Rong-Xin Zhang 《World Journal of Gastroenterology》 SCIE CAS 2018年第20期2181-2190,共10页
AIM To evaluate indoleamine-2,3-dioxygenase 1/cyclooxygenase 2(IDO1/COX2) expression as an independent prognostic biomarker for colorectal cancer(CRC) patients.METHODS We retrospectively studied the medical records of... AIM To evaluate indoleamine-2,3-dioxygenase 1/cyclooxygenase 2(IDO1/COX2) expression as an independent prognostic biomarker for colorectal cancer(CRC) patients.METHODS We retrospectively studied the medical records of 95 patients who received surgical resection from August 2008 to January 2010. All patients were randomly assigned to adjuvant treatment with or without celecoxib groups after surgery. We performed standard immunohistochemistry to assess the expression levels of IDO1/COX2 and evaluated the correlation of IDO1/COX2 with clinicopathological factors and overall survival(OS) outcomes.RESULTS The expression of nuclear IDO1 was significantly correlated with body mass index(P < 0.001), and IDO1 expression displayed no association with sex, age, tumor differentiation, T stage, N stage, carcinoembryonic antigen, cancer antigen 19-9, CD3+ and CD8+ tumor infiltrating lymphocytes, and COX2. In univariate analysis, we found that nuclear IDO1(P = 0.039), nuclear/cytoplasmic IDO1 [hazard ratio(HR) = 2.044, 95% confidence interval(CI): 0.871-4.798, P = 0.039], nuclear IDO1/COX2(HR = 3.048, 95%CI: 0.868-10.7, P = 0.0049) and cytoplasmic IDO1/COX2(HR = 2.109, 95%CI: 0.976-4.558, P = 0.022) all yielded significantly poor OS outcomes. Nuclear IDO1(P = 0.041), nuclear/cytoplasmic IDO1(HR = 3.023, 95%CI: 0.585-15.61, P = 0.041) and cytoplasmic IDO1/COX2(HR = 2.740, 95%CI: 0.764-9.831, P = 0.038) have significantly poor OS outcomes for the CRC celecoxib subgroup. In our multivariate Cox model, high coexpression of cytoplasmic IDO1/COX2 was found to be an independent predictor of poor outcome in CRC(HR = 2.218, 95%CI: 1.011-4.48, P = 0.047) and celecoxib subgroup patients(HR = 3.210, 95%CI: 1.074-9.590, P = 0.037).CONCLUSION Our results showed that cytoplasmic IDO1/COX2 coexpression could be used as an independent poor predictor for OS in CRC. 展开更多
关键词 PROGNOSIS Indoleamine-2 3-dioxygenase 1 CYCLOOXYGENASE 2 Colorectal cancer
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Inhibition of allogeneic T-cell response by Kupffer cells expressing indoleamine 2,3-dioxygenase 被引量:6
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作者 Yan, Mao-Lin Wang, Yao-Dong +2 位作者 Tian, Yi-Feng Lai, Zhi-De Yan, Lv-Nan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第5期636-640,共5页
AIM:To explore the possibility and mechanism of inhibiting allogeneic T-cell responses by Kupffer cells (KC)pretreated with interferon-γ(IFN-γ)in vitro. METHODS:The expressions of indoleamine 2,3-dioxygenase(IDO)mRN... AIM:To explore the possibility and mechanism of inhibiting allogeneic T-cell responses by Kupffer cells (KC)pretreated with interferon-γ(IFN-γ)in vitro. METHODS:The expressions of indoleamine 2,3-dioxygenase(IDO)mRNA and FasL mRNA in KC pretreated with IFN-γwere studied with real-time polymerase chain reaction(PCR).The catabolism of tryptophan by IDO from KC was analyzed by high performance liquid chromatography.Allogeneic T-cell response was used to confirm the inhibition of KC in vitro.The proliferation of lymphocytes was detected using[ 3 H]thymidine incorporation.Cell cycle and lymphocyte apoptosis were evaluated by flow cytometric assay. RESULTS:Real-time PCR revealed IDO mRNA and FasL mRNA expressions in KC pretreated with IFN-γ,and IDO catabolic effect was confirmed by a decrease in tryptophan and increase in kynurenine concentration. KC expressing IDO and FasL in BABL/c mice acquired the ability to suppress the proliferation of T-cells from C57BL/6,which could be blocked by addition of 1-methyl-tryptophan and anti-FasL antibody.KC expressing IDO could induce allogeneic T-cell apoptosisCONCLUSION:In addition to Fas/FasL pathway,IDO may be another mechanism for KC to induce immune tolerance. 展开更多
关键词 Kupffer cell FASL Indoleamine 2 3-dioxygenase T-cell proliferation
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Indoleamine 2,3-dioxygenase: As a potential prognostic marker and immunotherapeutic target for hepatocellular carcinoma 被引量:17
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作者 Kashif Asghar Asim Farooq +1 位作者 Bilal Zulfiqar Muhammad Usman Rashid 《World Journal of Gastroenterology》 SCIE CAS 2017年第13期2286-2293,共8页
Tumor cells induce an immunosuppressive microen-vironment which leads towards tumor immune escape. Understanding the intricacy of immunomodulation by tumor cells is essential for immunotherapy. Indoleamine 2,3-dioxyge... Tumor cells induce an immunosuppressive microen-vironment which leads towards tumor immune escape. Understanding the intricacy of immunomodulation by tumor cells is essential for immunotherapy. Indoleamine 2,3-dioxygenase(IDO) is an immunosuppressive enzyme which mediates tumor immune escape in various cancers including hepatocellular carcinoma(HCC). IDO up-regulation in HCC may lead to recruitment of regulatory T-cells into tumor microenvironment and therefore inhibit local immune responses and promote metastasis. HCC associated fibroblasts stimulate natural killer cells dysfunction through prostaglandin E2 and subsequently IDO promotes favorable condition for tumor metastasis. IDO up-regulation induces immuno-suppression and may enhance the risk of hepatitis C virus and hepatitis B virus induced HCC. Therefore, IDO inhibitors as adjuvant therapeutic agents may have clinical implications in HCC. This review proposes future prospects of IDO not only as a therapeutic target but also as a prognostic marker for HCC. 展开更多
关键词 Hepatocellular carcinoma Hepatitis C virus Hepatitis B virus Indoleamine 2 3-dioxygenase
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Expression of indoleamine 2,3-dioxygenase in a murine model of Aspergillus fumigatus keratitis 被引量:5
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作者 Nan Jiang Gui-Qiu Zhao +7 位作者 Jing Lin Li-Ting Hu Cheng-Ye Che Cui Li Qian Wang Qiang Xu Jie Zhang Xu-Dong Peng 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第4期491-496,共6页
AIM: To observe the presence and expression of indoleamine 2,3-dioxygenase(IDO) during the corneal immunity to Aspergillus fumigatus(A. fumigatus) in the murine models.·METHODS: The murine model of fungal k... AIM: To observe the presence and expression of indoleamine 2,3-dioxygenase(IDO) during the corneal immunity to Aspergillus fumigatus(A. fumigatus) in the murine models.·METHODS: The murine model of fungal keratitis was established by smearing with colonies of A. fumigatus after scraping central epithelium of cornea and covering with contact lenses in C57BL/6 mice. The mice were randomly divided into control group, sham group and A.fumigatus keratitis group. The cornea was monitored daily using a slit lamp and recorded disease score after infection. Corneal lesion was detected by immunofluorescence staining. IDO m RNA and protein were also detected by quantitative reverse transcription-polymerase chain reaction(q RT-PCR) and Western blot.· RESULTS: The disease score and slit lamp photography indicated that disease severity was consistent with corneal inflammation in the murine models, and the disease scores in A. fumigatus keratitis group were obviously higher than those in the sham group. By immunofluorescence staining, IDO was mainly localized in corneal epithelium and stroma in the murine corneal tissues with A. fumigatus keratitis. Compared with the sham group, IDO m RNA expression was significantly enhanced in corneal epithelium infected by A. fumigatus. Furthermore, IDO protein expression detected by Western blot was in accord with transcript levels of IDO m RNA measured by q RT-PCR. IDO protein expression was enhanced after A. fumigatus infection compared with the sham group.·CONCLUSION: IDO is detected in corneal epithelium and stroma locally, which indicates IDO takes part in the pathogenesis of A. fumigatus keratitis and plays a key role in immune regulation at the early stage. 展开更多
关键词 indoleamine 2 3-dioxygenase corneal epithelium fungal keratitis Aspergillus fumigatus innate immune response
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Molecular Cloning and Characterization of a New Cold-active Extradiol Dioxygenase from a Metagenomic Library Derived from Polychlorinated Biphenyl-contaminated Soil
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作者 REN He-jun LU Yang +3 位作者 ZHOU Rui DAI Chun-yan WANG Yah ZHANG Lan-ying 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第4期666-671,共6页
To find new extradiol dioxygenases(EDOs,EC 1.13.11.2),a metagenomics library was constructed from polychlorinated biphenyl-contaminated soil and was screened for some dioxygenase with aromatic ring cleavage activity... To find new extradiol dioxygenases(EDOs,EC 1.13.11.2),a metagenomics library was constructed from polychlorinated biphenyl-contaminated soil and was screened for some dioxygenase with aromatic ring cleavage activity.A novel EDO,designated as BphC_A,was identified and heterologously expressed in Escherichia coli.The deduced amino acid sequence of BphC_A exhibited a homology of less than 60% with other known EDOs.Phylogenetic analysis of BphC_A suggests that the protein is a novel member of the EDO family.The enzyme exhibits higher substrate affinity and catalytic efficiency toward 3-methylcatechol than toward 2,3-dihydroxybiphenyl or catechol,the preferred substrate of other known EDOs.The optimum activity of purified BphC_A occurred at pH=8.5 and 35 °C,and BphC_A showed more than 40% of its initial activity at 5 °C.The activity of purified BphC_A was significantly induced by Mn^2+ and slightly reduced by Al^3+,Cu^2+ and Zn^2+. 展开更多
关键词 Extradiol dioxygenase METAGENOME Cold-active enzyme Gene cloning Functional characterization
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Subcloning and high level expression of xylE gene coding for the catechol 2, 3 dioxygenase in E. coli
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作者 蔡在龙 王学敏 +4 位作者 毛积芳 季朝能 董海 沈仁权 毛裕民 《Journal of Medical Colleges of PLA(China)》 CAS 1997年第3期181-184,共4页
To construct a high-level expression of xylE gene in E. coli for quick detection of environmental pollution of aromatic compounds. Methods and Results: XylE gene coding for the catechol 2, 3 dioxygenase (CatO2ase ) wa... To construct a high-level expression of xylE gene in E. coli for quick detection of environmental pollution of aromatic compounds. Methods and Results: XylE gene coding for the catechol 2, 3 dioxygenase (CatO2ase ) was amplified from the recombinant plasmid pTG402 by using PCR technique and was subcloned into pUC118N and pUC119N. The single stranded recombinant phage DNA from the transformed E. coli MV1184 cells was used for sequencing. The sequence of xylE gene was proved to be the same as reported. The gene was then subcloned into the high expression plasmid pJLA503, its expression amount being about 34. 2% of the total bacterial proteins. Conclusion: xylE gene is highly expressed in host E. coli TG1. 展开更多
关键词 xylE GENE CATECHOL 2 3 dioxygenase GENE EXPRESSION
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Structural insights of 4-Hydrophenylpyruvate dioxygenase inhibition by structurally diverse small molecules 被引量:2
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作者 Jin Dong Jiangqing Dong +7 位作者 Xin-He Yu Yao-Chao Yan Jia-Xu Nan Bo He Bao-Qin Ye Wen-Chao Yang Hong-Yan Lin Guang-Fu Yang 《Advanced Agrochem》 2022年第2期174-181,共8页
4-Hydrophenylpyruvate dioxygenase(HPPD),a key enzyme involved in tyrosine catabolism,has long been considered a promising target for herbicides and drugs.Several types of HPPD inhibitors have been developed as high-po... 4-Hydrophenylpyruvate dioxygenase(HPPD),a key enzyme involved in tyrosine catabolism,has long been considered a promising target for herbicides and drugs.Several types of HPPD inhibitors have been developed as high-potency drugs or herbicides.Understanding the structural basis of the binding of these inhibitors with HPPD will be beneficial for the development of inhibitors containing novel scaffolds.However,only limited structural information regarding the binding of triketone and pyrazole derivatives with HPPD has been reported.Here,the crystal structures of HPPD complexed with inhibitors containing different scaffolds,including triketone,pyrazole,isoxazole,heterocyclic amide,and quinazolindione derivatives,were comprehensively analyzed.Detailed binding modes of isoxazole and heterocyclic amide derivatives with HPPD were first revealed,facilitating further structural optimization.The binding mode of compound 2 with HPPD suggests that both oxygen and nitrogen atoms can mediate coordination with the metal ion.These results will provide the structure-based rational design of novel HPPD inhibitors. 展开更多
关键词 4-Hydrophenylpyruvate dioxygenase(HPPD) Crystal structures INHIBITORS Binding mode HERBICIDE
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基于改进Alpha Shape算法的点云数据岛屿边界提取 被引量:1
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作者 宋晓辉 熊祖雄 +2 位作者 张炎 吕富强 韦建林 《海洋测绘》 CSCD 北大核心 2024年第1期58-62,共5页
针对机载LiDAR点云的岛屿岸线提取过程复杂、附属岛屿岸线难以提取等问题,提出一种基于改进Alpha Shape算法的点云数据岛屿边界提取方法。首先利用布料模拟滤波算法剔除非岛屿点云数据,通过欧式聚类进行不同岛屿的提取,再将岛屿点云数... 针对机载LiDAR点云的岛屿岸线提取过程复杂、附属岛屿岸线难以提取等问题,提出一种基于改进Alpha Shape算法的点云数据岛屿边界提取方法。首先利用布料模拟滤波算法剔除非岛屿点云数据,通过欧式聚类进行不同岛屿的提取,再将岛屿点云数据投影至二维平面,并根据岛屿点云构建格网。在此基础上使用自适应Alpha Shape算法,对提取出的岛屿点云进行边界提取,即可得到岛屿的岸线轮廓。选取新西兰的玛提尤/萨姆斯岛作为研究区域,并将本文算法与Alpha Shape算法进行对比,结果表明:本文算法提取岛屿边界点云的精准度为97.78%,可以准确地提取岛屿岸线,为海岛规划提供参考。 展开更多
关键词 摄影测量 机载LiDAR点云 边界提取 欧式聚类 自适应alpha Shape
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Regulation of A 9-cis-epoxycarotenoid Dioxygenase(NCED)Gene from Raspberry on High Salinity and Cold Tolerance
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作者 Yang Guo-hui Li Bo-lin +3 位作者 Wang Ze-min Yu Hang Wang Jia-ming Li Tie-mei 《Journal of Northeast Agricultural University(English Edition)》 CAS 2023年第2期32-42,共11页
Abscisic acid(ABA)is a plant hormone that plays an important role in plant development and abiotic stress.The 9-cis-epoxycarotenoid dioxygenase(NCED)is a key rate-limiting enzyme in the ABA biosynthetic pathway.The ph... Abscisic acid(ABA)is a plant hormone that plays an important role in plant development and abiotic stress.The 9-cis-epoxycarotenoid dioxygenase(NCED)is a key rate-limiting enzyme in the ABA biosynthetic pathway.The physiological and molecular mechanisms of NCED regulating plant development and abiotic stress tolerance have been reported in many plant species,but gene function of RiNCEDs in Rubus idaeus L.is rarely reported.In this study,the open reading frame(ORF)sequence of RiNCED2 in red raspberry fruit was isolated and the function of this gene under abiotic stress was investigated.While RiNCED2 was induced by cold,high salinity,drought and ABA,it was highly expressed in new leaves as measured by real-time qPCR.Overexpression of RiNCED2 in Arabidopsis under both high-salt and cold stress increased ABA content,demonstrating that RiNCED2 was involved in ABA biosynthesis.Meanwhile,the leaf wilting degree of transgenic Arabidopsis was less,while the content of malondialdehyde(MDA)was significantly reduced,and the chlorophyll content,proline content,peroxidase(POD),catalase(CAT)and superoxide dismutase(SOD)activities were significantly increased.These results indicated that overexpression of RiNCED2 enhanced the resistance of transgenic Arabidopsis to high salt and cold. 展开更多
关键词 9-cis-epoxycarotenoid dioxygenase RASPBERRY high salt cold
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慢性失眠合并轻度认知功能障碍老年患者顶枕叶alpha脑电频谱特征研究
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作者 郭振兴 白林鑫 +3 位作者 张琳 高佳慧 饶婷 刘志臻 《康复学报》 CSCD 2024年第6期597-603,共7页
目的分析慢性失眠合并轻度认知功能障碍(MCI)老年患者顶枕叶alpha脑电频谱特征。方法选择2019年6月—2020年12月福建省福州市鼓东、温泉社区老年受试者80例,其中健康对照组(HC组)30例、慢性失眠组(CI组)20例、慢性失眠合并MCI组(CI-MCI... 目的分析慢性失眠合并轻度认知功能障碍(MCI)老年患者顶枕叶alpha脑电频谱特征。方法选择2019年6月—2020年12月福建省福州市鼓东、温泉社区老年受试者80例,其中健康对照组(HC组)30例、慢性失眠组(CI组)20例、慢性失眠合并MCI组(CI-MCI组)30例。采用匹兹堡睡眠质量指数(PSQI)评估睡眠质量;采用福州版蒙特利尔认知评估量表(MoCA)评估受试者认知功能(视空间执行、命名、注意力、言语流畅性、抽象力、延迟回忆和定向力);采用Neuroscan 64导联脑电仪同步脑电记录系统采集日间静息态脑电波(EEG),对比顶枕叶alpha(8~13 Hz)各通道功率值的差异及变化趋势;分析顶枕叶alpha频谱功率的改变与认知功能的相关性。结果(1)PSQI评分:与HC组比较,CI-MCI组日间功能障碍评分明显升高,差异具有统计学意义(P<0.05);CI组、CI-MCI组PSQI总分、睡眠质量、入睡时间、睡眠时间、睡眠效率、睡眠障碍评分均明显升高,催眠药物评分明显降低,差异均具有统计学意义(P<0.05)。(2)MoCA评分:与HC组、CI组比较,CI-MCI组MoCA总分、视空间执行、命名、注意力、语言流畅性、抽象力、延迟回忆、定向力评分均明显降低,差异均具有统计学意义(P<0.05)。(3)EEG频谱特征:与HC组比较,CI-MCI组顶枕叶P1、P6、POZ、PO4、PO6 alpha频谱功率均明显增强,差异均具有统计学意义(P<0.05);与HC组比较,CI-MCI组顶枕叶alpha频谱地形图呈现出频谱功率较强的现象。(4)顶枕叶alpha频谱功率的改变与认知功能的相关性:P6右顶叶alpha频谱功率(r=0.444,P=0.023)、POZ顶枕叶alpha频谱功率(r=0.444,P=0.023)、PO4右顶枕叶alpha频谱功率(r=0.478,P=0.014)均与视空间执行功能呈正相关关系。结论顶枕叶alpha频谱功率变化是慢性失眠合并MCI老年患者认知功能损伤的表现;顶枕叶alpha频谱功率可调节慢性失眠合并MCI老年患者的认知功能。 展开更多
关键词 慢性失眠 轻度认知功能障碍 alpha频谱 顶枕叶 老年患者
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2-Oxoglutarate-dependent dioxygenases in plants:biosynthesis,mechanism and evolution
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作者 Lin Maa Yifeng Zhanga Wei Gao 《Asian Journal of Traditional Medicines》 CAS 2021年第4期240-253,共14页
2-Oxoglutarate(2OG)-dependent dioxygenases(2-ODDs)are omnipresent iron-containing non-heme enzymes that catalyze various oxidation-reduction reactions in plant growth and development,nucleic acid modification and seco... 2-Oxoglutarate(2OG)-dependent dioxygenases(2-ODDs)are omnipresent iron-containing non-heme enzymes that catalyze various oxidation-reduction reactions in plant growth and development,nucleic acid modification and secondary metabolism.We systematically summarized recent research on the oxidative modifications of plant 2-ODDs and related enzymes,their vital importance in the biosynthesis of plant special metabolites,and their catalytic specificity/flexibility,and discussed the potential of 2-ODD as a new approach for the identification of pivotal genes and the elucidation of biosynthetic pathway. 展开更多
关键词 2-oxoglutarate-dependent dioxygenase secondary metabolism flavonoid TERPENOID BIOSYNTHESIS
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Expression of the C-Terminal Domain of Mammalian TET3 DNA Dioxygenase in Arabidopsis thaliana Induces Heritable Methylation Changes at rDNA Loci
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作者 Elizabeth Hollwey Michael Watson Peter Meyer 《Advances in Bioscience and Biotechnology》 2016年第5期243-250,共8页
In plants, demethylation of 5-methylcytosine (5 mC) residues is controlled by DNA glycosylases, while in mammals it requires oxidation of 5 mC by TET proteins, a group of Fe(II)/2-oxoglutaratedependent dioxygenases. W... In plants, demethylation of 5-methylcytosine (5 mC) residues is controlled by DNA glycosylases, while in mammals it requires oxidation of 5 mC by TET proteins, a group of Fe(II)/2-oxoglutaratedependent dioxygenases. We analysed the effects of expressing the C-terminal catalytic domain of the human TET3 gene (TET3c) in Arabidopsis thaliana, using an rDNA region as a methylation reporter. In TET3c transformants, epialleles with hypomethylation or hypermethylation patterns can be induced, which is each stably retained in progeny lines even after removal of the TET3c transgene. In TET3c transformants, 5-hydroxymethylcytosine (5 hmC) marks are detected, indicative of the oxidative activity of the transgenic enzyme. 5-formylcytosine (5 fC) is only detectable in TET3c transformants with a DNA glycosylase mutant background suggesting further oxidation of 5 hmC residues to 5 fC by TET3c, and efficient recognition and removal of 5 fC by plant glycosylases. The results suggest that TET3c can be employed to induce heritable locus-specific changes in DNA methylation, and that accumulation of 5 hmC can be used as a marker for TET3c target regions. 展开更多
关键词 Arabidopsis thaliana DNA Methylation DNA Demethylation Ten-Eleven-Translocation (TET) Proteins dioxygenase 5-Hydroxy-Methylcytosine (5 hmC) 5-Formyl-Cytosine 1.
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Relationship of Abortion and the Expression of Indoleamine 2,3- dioxygenase (IDO) in Villus and Syncytiotrophoblasts
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作者 Xue-lian LI Sui-qi GUI Hai-yan WANG 《Journal of Reproduction and Contraception》 CAS 2005年第4期235-242,共8页
Objective To study the relationship of abortion and the expression of indoleamine 2, 3- dioxygenase (IDO) in villus and syncytiotrophoblast in vitro. Methods RT-PCR was applied to analyze the mRNA transcription of l... Objective To study the relationship of abortion and the expression of indoleamine 2, 3- dioxygenase (IDO) in villus and syncytiotrophoblast in vitro. Methods RT-PCR was applied to analyze the mRNA transcription of lDO in villus of normal pregnancy and inevitable abortion and JAR cells as well. Immunohistochemistry was applied to analyze the expression of IDO protein in villus. Western blot was applied to determinate the expression of IDO protein on cultured syncytiotrophoblast. Highperformance liquid chromatography was applied to determinate whether there was kynurenine in cell culture medium of syncytiotrophoblast. Results The expression of IDO mRNA and protein in villus of inevitable abortion was lower than that of normal pregnancy; IDO mRNA did not express in JAR cells. IDO protein expressed on cultured syncytiotrophoblast, and there was kynurenine in cell culture medium of syncytiotrophoblast. Conclusion Appropriate expression of IDO in villus is necessary.for maintenance of normal pregnancy and an active IDO protein expresses in syncytiotrophoblast. 展开更多
关键词 indoleamine 2 3-dioxygenase syncytiotrophoblast VILLUS ABORTION
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