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散发性乳腺癌中MTA1表达与ERα甲基化关系的研究 被引量:2
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作者 孙亚楠 郭阿垚 +3 位作者 毛晓韵 陈浩 刘崇 金锋 《现代肿瘤医学》 CAS 2013年第6期1228-1231,共4页
目的:通过甲基化特异性PCR和免疫组化研究女性散发性乳腺癌中ERα基因启动子区甲基化和MTA1蛋白表达的相关性。方法:甲基化PCR研究102例散发性乳腺癌ERα启动子甲基化情况,免疫组化研究其MTA1蛋白表达情况。结果:乳腺癌组织中ERα启动... 目的:通过甲基化特异性PCR和免疫组化研究女性散发性乳腺癌中ERα基因启动子区甲基化和MTA1蛋白表达的相关性。方法:甲基化PCR研究102例散发性乳腺癌ERα启动子甲基化情况,免疫组化研究其MTA1蛋白表达情况。结果:乳腺癌组织中ERα启动子甲基化率为37.3%,乳腺癌组织中MTA1表达率为29.4%,高于其在癌旁正常乳腺组织中的表达(P<0.05),MTA1表达和ERα启动子甲基化均与乳腺肿瘤大小、TNM分期及淋巴结转移相关(P<0.05),且乳腺癌中ERα启动子甲基化与MTA1阳性表达呈正相关(P<0.05)。结论:女性散发性乳腺癌中ERα基因启动子甲基化与MTA1表达升高密切相关,其在乳腺癌发展过程中可能起重要作用。 展开更多
关键词 乳腺癌 MTA1 ERα甲基
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α-甲基丙烯酸烯丙酯的合成及其自由基、阴离子聚合的研究 被引量:4
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作者 张洪敏 侯元雪 程羽中 《合成化学》 CAS CSCD 1996年第3期271-274,共4页
合成了α-甲基丙烯酸烯丙酯(AMA),并对其自由基、阴离子聚合进行了探讨。结果发现,该单体难以进行选择性自由基聚合,但可用作多种单体自由基聚合的交联剂。用1,1′-二苯基己基锂在THF中引发AMA,可顺利地进行α位双... 合成了α-甲基丙烯酸烯丙酯(AMA),并对其自由基、阴离子聚合进行了探讨。结果发现,该单体难以进行选择性自由基聚合,但可用作多种单体自由基聚合的交联剂。用1,1′-二苯基己基锂在THF中引发AMA,可顺利地进行α位双键的选择性阴离子聚合,分子量实测值与计算值基本一致。在较低温度下(≤-60℃),可得窄分布PAMA(Mw/Mn=1.12~1.15)。随聚合温度升高,间同和无规聚合物含量分别呈下降和上升趋势。GPC、1HNMR及FTIR鉴定表明,用阴离子聚合法可得到溶于多种溶剂、每个重复单元上均定量带有烯丙基双键的窄分布官能性PAMA。 展开更多
关键词 自由基聚合 阴离子聚合 α甲基 丙烯酸烯丙酯
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MTA1在乳腺癌MDA-MB-231和MDA-MB-435s细胞系的表达及与ERα甲基化的关系 被引量:3
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作者 刘崇 毛晓韵 金锋 《解剖科学进展》 CAS 2015年第3期233-235,240,共4页
目的用去甲基化药物5-Aza-d C处理雌激素受体α(estrogen receptorα,ERα)启动子甲基化的乳腺癌细胞系,探讨ERα启动子甲基化与MTA1在乳腺癌发生发展中的可能机制。方法用去甲基化药物5-Aza-d C逆转MDA-MB-231和MDA-MB-435s的ERα启动... 目的用去甲基化药物5-Aza-d C处理雌激素受体α(estrogen receptorα,ERα)启动子甲基化的乳腺癌细胞系,探讨ERα启动子甲基化与MTA1在乳腺癌发生发展中的可能机制。方法用去甲基化药物5-Aza-d C逆转MDA-MB-231和MDA-MB-435s的ERα启动子甲基化,甲基化PCR验证其甲基化状态,用RT-PCR和Western blot研究去甲基化后MTA1 m RNA和蛋白表达情况,Transwell检测去甲基化后细胞侵袭能力的改变。结果在MDA-MB-231和MDA-MB-435s细胞系中,去甲基化药物5-Aza-d C逆转ERα启动子甲基化后,MTA1m RNA和蛋白表达水平下调,细胞侵袭能力下降。结论乳腺癌细胞系MDA-MB-231和MDA-MB-435s中ERα甲基化与MTA1表达存在相关性。 展开更多
关键词 乳腺癌 MTA1 雌激素受体α甲基
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17α-甲基睾丸素4,5位双键过氧化氢氧化和浓硫酸破坏产物的探讨
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作者 汪午 史建栋 《中国药物化学杂志》 CAS CSCD 1997年第2期125-128,共4页
以17α-甲基睾丸素为底物,过氧化氢为氧化剂,在浓硫酸环境中,经自由基历程,最终脱去19位角甲基.反应混合液经提取、过柱等一系列后处理,结果得到两种白色针状晶体:雄甾-17α-甲基-17β-羟基-4-甲氧基-5-烯-... 以17α-甲基睾丸素为底物,过氧化氢为氧化剂,在浓硫酸环境中,经自由基历程,最终脱去19位角甲基.反应混合液经提取、过柱等一系列后处理,结果得到两种白色针状晶体:雄甾-17α-甲基-17β-羟基-4-甲氧基-5-烯-3-酮(MT-131)和雄甾-19-去甲基-17α-甲基-6,17β-二羟基-4-甲氧基-3-酮(MT-140),产率分别为21%和9%.结构经元素分析、红外光谱、质谱和核磁共振氢谱确证. 展开更多
关键词 药物化学 17α甲基睾丸素 过氧化氢 氧化
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血清PSA、TGF-β_(1)、uPAR、AMACR和尿肌氨酸在前列腺癌诊断中的效能分析 被引量:9
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作者 李娜 左树森 乔玉华 《山东医药》 CAS 2023年第5期71-74,共4页
目的通过检测前列腺癌(PCa)患者血清前列腺特异性抗原(PSA)、转化生长因子β_(1)(TGF-β_(1))、尿激酶型纤溶酶原激活物(uPAR)、α甲基酰基辅酶A消旋酶(AMACR)和尿肌氨酸水平,探讨上述指标在前列腺癌诊断中的效能。方法选取PCa患者80例... 目的通过检测前列腺癌(PCa)患者血清前列腺特异性抗原(PSA)、转化生长因子β_(1)(TGF-β_(1))、尿激酶型纤溶酶原激活物(uPAR)、α甲基酰基辅酶A消旋酶(AMACR)和尿肌氨酸水平,探讨上述指标在前列腺癌诊断中的效能。方法选取PCa患者80例为PCa组,同时按1∶1选取前列腺良性增生患者及体检健康者分别作为良性增生组及健康对照组。采用ELISA法检测血清TGF-β_(1)、uPAR、AMACR,电化学发光法检测血清PSA,同位素稀释液相色谱质谱法测定尿沉渣中的肌氨酸;对比各指标在三组间及不同临床病理特征PCa患者间的差异,采用受试者工作特征(ROC)曲线分析各指标单项与联合对PCa的诊断价值。结果PCa组血清PSA、TGF-β_(1)、uPAR、AMACR及尿肌氨酸水平均高于良性增生组和健康对照组,且良性增生组高于健康对照组(P均<0.05)。PCa患者血清PSA、TGF-β_(1)、uPAR及尿肌氨酸水平均随Gleason评分及TNM分期升高而逐渐升高(P均<0.05),且有骨转移者血清PSA、TGF-β_(1)、uPAR、AMACR及尿肌氨酸水平均高于无骨转移者(P均<0.05)。单项检测时,AMACR诊断PCa的约登指数、灵敏度及准确度最高,尿肌氨酸诊断的ROC曲线下面积(AUC)及特异度最高;各指标联合检测对PCa诊断的AUC明显高于各单项检测(P均<0.05)。结论PCa患者血清TGF-β_(1)、uPAR、AMACR及尿肌氨酸水平升高,且随病情加重升高越明显;各指标对PCa均有一定诊断价值,但联合诊断效能最高。 展开更多
关键词 前列腺特异性抗原 转化生长因子β_(1) 尿激酶型纤溶酶原激活物 α甲基酰基辅酶A消旋酶 尿肌氨酸 前列腺癌
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肾移植术后孕妇心肾衰竭一例
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作者 周寅 曲元 《临床麻醉学杂志》 CAS CSCD 北大核心 2017年第7期725-725,共1页
肾移植后妊娠是高危妊娠,较为罕见。了解肾移植术后的治疗和管理,有助于做出更好的临床决策,保证母婴安全。患者,女,31岁,因"孕30^+1周,胸闷、浮肿半月"急诊入院。孕24周时,BP 150/100 mm Hg,加用硝苯地平缓释片30mg,后改为氨氯地平5... 肾移植后妊娠是高危妊娠,较为罕见。了解肾移植术后的治疗和管理,有助于做出更好的临床决策,保证母婴安全。患者,女,31岁,因"孕30^+1周,胸闷、浮肿半月"急诊入院。孕24周时,BP 150/100 mm Hg,加用硝苯地平缓释片30mg,后改为氨氯地平5 mg,孕28周时,BP 160/100mm Hg。 展开更多
关键词 硝苯地平缓释片 高危妊娠 临床决策 心肾 移植肾 α甲基多巴 目标水平 左房扩大 自然分娩 全身水肿
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Effectiveness of Saccharomyces boulardii in a rat model of colitis 被引量:6
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作者 Mujde Soyturk Saba Mukaddes Saygili +4 位作者 Huseyin Baskin Ozgul Sagol Osman Yilmaz Fatih Saygili Hale Akpinar 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第44期6452-6460,共9页
AIM:To investigate the effects of Saccharomyces boulardii(S.boulardii) in an experimental rat model of trinitrobenzene sulfonic acid(TNBS)-induced colitis.METHODS:Thirty-two Wistar albino female rats were categorized ... AIM:To investigate the effects of Saccharomyces boulardii(S.boulardii) in an experimental rat model of trinitrobenzene sulfonic acid(TNBS)-induced colitis.METHODS:Thirty-two Wistar albino female rats were categorized into five groups.On the first day of the study,50 mg TNBS was administered via a rectal catheter in order to induce colitis in all rats,except those in the control group.For 14 d,the rats were fed a standard diet,without the administration of any additional supplements to either the control or TNBS groups,in addition to 1 mg/kg per day S.boulardii to the S.boulardii group,1 mg/kg per day methyl prednisolone(MP) to the MP group.The animals in the S.boulardii + MP group were coadministered these doses of S.boulardii and MP.During the study,weight loss,stool consistency,and the presence of obvious blood in the stool were evaluated,and the disease activity index(DAI) for colitis was recorded.The intestines were examined and colitis was macro-and microscopically scored.The serum and tissue levels of tumor necrosis factor-α(TNF-α) and nitric oxide(NO) were determined,and fungemia was evaluated in the blood samples.RESULTS:The mean DAI scores for the MP and S.boulardii + MP groups was significantly lower than the TNBS group(3.69 ± 0.61 vs 4.46 ± 0.34,P = 0.018 and 3.77 ± 0.73 vs 4.46 ± 0.34,P = 0.025,respectively).While no significant differences between the TNBS and the S.boulardii or MP groups could be determined in terms of serum NO levels,the level of serum NO in the S.boulardii + MP group was significantly higher than in the TNBS and S.boulardii groups(8.12 ± 4.25 μmol/L vs 3.18 ± 1.19 μmol/L,P = 0.013;8.12 ± 4.25 μmol/L vs 3.47 ± 1.66 μmol/L,P = 0.012,respectively).The tissue NO levels in the S.boulardii,MP and S.boulardii + MP groups were significantly lower than the TNBS group(16.62 ± 2.27 μmol/L vs 29.72 ± 6.10 μmol/L,P = 0.002;14.66 ± 5.18 μmol/Lvs 29.72 ± 6.10 μmol/L,P = 0.003;11.95 ± 2.34 μmol/Lvs 29.72 ± 6.10 μmol/L,P = 0.002,respectively).The tissue NO levels in the S.boulardii,MP and S.boulardii + MP groups were similar.The mean serum and tissue TNF-α levels were determined to be 12.97 ± 18.90 pg/mL and 21.75 ± 15.04 pg/mL in the control group,18.25 ± 15.44 pg/mL and 25.27 ± 11.95 pg/mL in the TNBS group,20.59 ± 16.15 pg/mL and 24.39 ± 13.06 pg/mL in the S.boulardii group,9.05 ± 5.13 pg/mL and 24.46 ± 10.85 pg/mL in the MP group,and 13.95 ± 10.17 pg/mL and 24.26 ± 10.37 pg/mL in the S.boulardii + MP group.Significant differences in terms of the levels of serum and tissue TNF-α and the macroscopic and microscopic scores were not found between the groups.S.boulardii fungemia was not observed in any of the rats.However,Candida fungemia was detected in one rat(14%) in the TNBS group,two rats(28%) in the S.boulardii group,three rats(50%) in the MP group,and three rats(42%) in S.boulardii + MP group.CONCLUSION:S.boulardii does not demonstrate considerable effects on the DAI,pathological scores,or cytokine levels but does decrease the tissue NO levels. 展开更多
关键词 Saccharomyces boulardii RAT Trinitroben-zene sulfonic acid Tumor necrOsis factor-m Nitric ox-ide FUNGEMIA
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Synthesis and Crystal Structure of O,O-Dimethyl-N-(β-triphenylgermanyl)propionyl-α- aminobenzylphosphonates 被引量:2
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作者 叶勇 曾强 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第3期195-198,共4页
The title compound (C30H32NO4PGe), O,O-dimethyl-N-(β-triphenylgermanyl) propionyl-α-aminobenzylphosphonates was synthesized by a convenient method, and its crystal structure was determined by single-crystal X-ray di... The title compound (C30H32NO4PGe), O,O-dimethyl-N-(β-triphenylgermanyl) propionyl-α-aminobenzylphosphonates was synthesized by a convenient method, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal is triclinic, space group P-1 with parameters: a=9.7753(5), b=11.5773(5), c=13.5059(6) ?, α=104.185(1),β= 95.971(1), γ =96.727(1)°, V=1457.63(12) ?3, Z=2, Mr=574.13, Dc=1.308 g/cm3, λ=0.71073 ?, μ = 1.139mm-1, and F(000)=596. The structure was solved by direct methods. The structure was refined to R=0.0257, wR=0.0705 for 5080 observed reflections with I >2σ(I).The result of structure analysis indicates that atom Ge is sp3 hydridized because the arrangement of the four carbon atoms bonded to it is a distorted tetrahedron. The geometry of the three phenyl groups linking with the Ge atom looks like a propeller form. 展开更多
关键词 crystal structure α-aminobenzylphosphonates β-triphenylgermanyl propionic acid SYNTHESIS
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Structural insights into a novel histone demethylase PHF8 被引量:11
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作者 Lin Yu Yang wang +8 位作者 Shuo Huang Jianjun Wang Zengqin Deng Qi Zhang Wei Wu Xingliang Zhang Zhao Liu Weimin Gong Zhongzhou Chen 《Cell Research》 SCIE CAS CSCD 2010年第2期166-173,共8页
Dynamic regulation of histone methylation/demethylation plays an important role during development. Mutations and truncations in human plant homeodomain (PHD) finger protein 8 (PHF8) are associated with X-linked m... Dynamic regulation of histone methylation/demethylation plays an important role during development. Mutations and truncations in human plant homeodomain (PHD) finger protein 8 (PHF8) are associated with X-linked mental retardation and facial anomalies, such as a long face, broad nasal tip, cleft lip/cleft palate and large hands, yet its molecular function and structural basis remain unclear. Here, we report the crystal structures of the catalytic core of PHF8 with or without α-ketoglutarate (α-KG) at high resolution. Biochemical and structural studies reveal that PHF8 is a novel histone demethylase specific for di- and mono-methylated histone H3 lysine 9 (H3K9me2/1), but not for H3K9me3. Our analyses also reveal how human PHF8 discriminates between methylation states and achieves sequence specificity for methylated H3K9. The in vitro demethylation assay also showed that the F279S mutant observed in clinical patients possesses no demethylation activity, suggesting that loss of enzymatic activity is crucial for pathogenesis of PHF8 patients. Taken together, these results will shed light on the molecular mechanism underlying PHF8-associated developmental and neurological diseases. 展开更多
关键词 PHF8 (PHD finger protein 8) histone demethylase chromatin modification methylated H3K9 crystal structure X-linked mental retardation (XLMR) facial anomalies
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Synthesis and Property Studies of Transparent Resins Containing Rare Earth Complex Eu(Ⅲ) (TTA)_2(MA)_2 Phen·H_2O
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作者 赵曙辉 李文刚 +1 位作者 赵圣印 曾宇迪 《Journal of Donghua University(English Edition)》 EI CAS 2009年第4期379-383,共5页
A new rare earth complex Eu(III) (TTA)2(MA)2Phen · H2O was synthesized and characterized by element analysis, FTIR, UV, thermal analysis, and fluorescence spectra. The strong fluorescence and high thermal s... A new rare earth complex Eu(III) (TTA)2(MA)2Phen · H2O was synthesized and characterized by element analysis, FTIR, UV, thermal analysis, and fluorescence spectra. The strong fluorescence and high thermal stability of Eu(III) (TTA)2(MA)2Phen · H2O were used to modify resin. The copolymer containing europium was prepared by copolymerization of Eu(III) and styrene/α- methylacrylic acid, and characterized by FTIR and fluorescence spectra. The fluorescence spectra showed that the copolymer was a sort of materials with good fluorescence property, and the higher fluorescence intensity came from the higher europium content. 展开更多
关键词 COPOLYMERIZATION EUROPIUM 2 - thenoyltrifluoroacetone complex PHOTOLUMINESCENCE
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Synthesis,Crystal Structure and Absolute Configuration of (+)-(a-Hydroxybenzyl)phenylphosphinic acid
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作者 蔡觉晓 周正洪 +1 位作者 唐除痴 王宏根 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第4期368-370,共3页
The title compound (+)-(a-hydroxybenzyl)phenylphosphinic acid (C13H13O3P, Mr = 248.20) has been synthesized and characterized by 31P NMR, 1H NMR and elemental analysis. X-ray diffraction analysis at 293(2) K indicates... The title compound (+)-(a-hydroxybenzyl)phenylphosphinic acid (C13H13O3P, Mr = 248.20) has been synthesized and characterized by 31P NMR, 1H NMR and elemental analysis. X-ray diffraction analysis at 293(2) K indicates that the compound belongs to monoclinic system, space group C2 with cell parameters: a = 23.560(8), b = 6.947(2), c = 7.854(3) ? b = 91.273(6)? V = 1285.2(7) 3, Z = 4, Dc = 1.283 g/cm3, F(000) = 520 and m(MoKa) = 0.207 mm-1. The number of independent reflections amounts to 1991, of which 1507 are observed reflections. The crystal structure has been determined by direct methods (SHELXL-97). The structure parameters are refined by full-matrix least-squares on F2 to R = 0.0437 and wR = 0.0893. The flack x parameter is 0.0001. The absolute configuration of the a-carbon in the title compound is S. 展开更多
关键词 a-hydroxyphosphinic acid (+)-(a-hydroxybenzyl)phenylphosphinic acid crystal structure absolute configuration
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Upregulation of TNF-α mRNA in hepatic fibrosis rats induced by dimethylnitrosamine 被引量:1
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作者 张斌 王灵台 《Journal of Medical Colleges of PLA(China)》 CAS 2007年第5期279-282,共4页
Objective:To observe the expression level of TNF-α mRNA in rats with hepatic fibrosis induced by dimethylnitrosamine (DMN) and to explore its relationship with collagen metabolism and its diagnostic value for hepatic... Objective:To observe the expression level of TNF-α mRNA in rats with hepatic fibrosis induced by dimethylnitrosamine (DMN) and to explore its relationship with collagen metabolism and its diagnostic value for hepatic fibrosis.Methods: Twenty-five male Wistar rats were randomly divided into normal control group (n=10) and model group (n=15). Model rats were induced by DMN for 4 weeks and at final stage were executed. TNF-α mRNA were detected by RT-PCR and the inflammatory necrosis and collagen deposition in hepatic tissue were observed by HE stain and Sirius red stain. The liver functions were determined by automatic biochemical analytic device. The serum marks of liver fibrosis, such as HA, LN and Ⅳ-C were measured with ELISA and RIA. Results: In this study, the rat model of liver fibrosis induced by DMN was successfully constructed. RT-PCR reveals that TNF-α mRNA expression in control group is lower than that of model group. The liver functions of model group were impaired compared with those of the control group (P<0.01). Semi-quantitive analysis revealed that TNF-α/β-actin of normal rats was 0.39±0.12, while 0.93±0.05 of model rats. The concentration of HA (434.44±98.81 vs 252.9±26.59 ng/ml, P<0.01), LN (70.67±6.32 vs 37.90±5.97 ng/ml, P<0.01) and Ⅳ-C (79.39±10.52 vs 21.40±4.17 ng/ml, P<0.01) were significantly increased in the model group as well. Changes of the indexes were similar to the pathological damage of the liver. Conclusion: The results suggested that activation of TNF-α in liver tissues may be the common pathogenic mechanism of liver fibrosis. TNF-α may be a useful index for the diagnosis of hepatic fibrosis which worthies further investigation. 展开更多
关键词 RATS hepatic fibrosis dimethylnitrosamine TNF-Α
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Relationship between Expression of the Human Alpha-Fetoprotein Gene and DNA Methylation Status of the Promoter Region
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作者 Lijun Chen Wei Wang Qiuyue Jin Ruimin Wang Wenliang Hu 《Chinese Journal of Clinical Oncology》 CSCD 2006年第5期364-369,共6页
OBJECTIVE DNA methylation has been regarded as an important epige-netic signature reflecting the transcription state of DNA in cells. This study was to conducted to assess the relationship between human alpha-feto-pro... OBJECTIVE DNA methylation has been regarded as an important epige-netic signature reflecting the transcription state of DNA in cells. This study was to conducted to assess the relationship between human alpha-feto-protein (AFP) gene expression and the DNA methylation status of the promoter region in three different cells, namely two human hepatocellular carcinoma (HCC) cell lines and normal human fibroblasts. METHODS Transcription of the AFP gene was verified by RT-PCR. After bisulphate treatment of DNA, the methods of MSP and BSP were used to analyze the methylation density and status within single DNA strands of two closely spaced CpG dinucleotides of the promoter region in the different cells. RESULTS RT-PCR analysis indicated that the expression of the AFP gene in HepG2 cells was significantly higher than in SMMC-7721 cells, and that the AFP gene was not expressed in normal human fibroblasts. By MSP and BSP we observed that the promoter region was demethylat-ed in the AFP-high-expressing cell lines, and that the sites of -2,494 bp and -2,431 bp in the AFP genomic sequence can be used as detection sites for early tumorous diagnosis. CONCLUSION These results indicate that the DNA methylation state of the promoter region has a negative correlation with AFP gene expression. 展开更多
关键词 ALPHA-FETOPROTEIN METHYLATION gene expression tumor.
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Optimization of technological conditions for one-pot synthesis of (S)-α-cyano-3-phenoxybenzyl acetate in organic media 被引量:1
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作者 章亭洲 杨立荣 朱自强 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第3期175-181,共7页
Optically active form of α-cyano-3-phenoxybenzyl (CPB) alcohol, building block of pyrethroid insecticides, was synthesized as its acetate by the combination of anion-exchange resin (D301)-catalyzed transcyanation bet... Optically active form of α-cyano-3-phenoxybenzyl (CPB) alcohol, building block of pyrethroid insecticides, was synthesized as its acetate by the combination of anion-exchange resin (D301)-catalyzed transcyanation between m-phenoxybenzaldehyde (m-PBA) and acetone cyanohydrin (AC), and lipase (from Alcaligenes sp.)-catalyzed enantioselective transesterification of the resulting cyanohydrin with vinyl acetate. Through optimizing technological conditions, the catalyzing efficiency was improved considerably compared to methods previously reported. Concentrations of CPB acetate were determined by gas chromatograph. The enantio excess (e.e.) values of CPB acetate were measured by NMR (nuclear magnetic resonance) method. Effects of solvents and temperatures on this reaction were studied. Cyclohexane was shown to be the best solvent among the three tested solvents. 55 °C was the optimal temperature for higher degree of conversion. External diffusion limitation was excluded by raising the rotational speed to 220 r/min. However, internal diffusion could not be ignored, since the catalyst (lipase) was an immobilized enzyme and its particle dimension was not made small enough. The reaction rate was substantially accelerated when the reactant (m-PBA) concentration was as high as 249 mmol/L, but decreased when the initial concentration of m-PBA reached to 277 mmol/L. It was also found that the catalyzing capability of recovered lipase was high enough to use several batches. Study of the mole ratio of AC to m-PBA showed that 2:1 was the best choice. The strategy of adding base catalyst D301 was found to be an important factor in improving the degree of conversion of the reaction from 20% to 80%. The highest degree of conversion of the reaction has reached up to 80%. 展开更多
关键词 Biosynthesis α-cyano-3-phenoxybenzyl (CPB) acetate LIPASE OPTIMIZATION Organic media
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Chiral Phosphine Ligands Derived from Sugars8. Crystal and Molecular Structure of Diphenyl (methyl 4', 6'-O-benzylidene-2'-deoxy-α-D-altropyranoside-2-)phosphine Oxide 被引量:1
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作者 施继成 汪汉卿 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1997年第1期11-15,共5页
The crystal structure of the title compound, C26H27O6P, has been determined by single--crystal X-ray diffraction. The crystal is monoclinic with space groupP21, a=16. 193(l), b=5. 804(1), c=12. 512(2) A, β=93. 187(5)... The crystal structure of the title compound, C26H27O6P, has been determined by single--crystal X-ray diffraction. The crystal is monoclinic with space groupP21, a=16. 193(l), b=5. 804(1), c=12. 512(2) A, β=93. 187(5)°, V=1174. 13A3, Dc=1. 319 g/cm3, F(000) =492, μ= 13. 52 cm-1, Z= 2, and final R= 0. 042and Rw= 0. 040 for 2349 reflections (I≥3σ(I)). Structure analysis revealed that thepyranose and 4, 6-O-benzylidene ring of the title compound adopts a distorted chair conformation. 展开更多
关键词 chiral phosphine oxide α-D-allopyranoside α-D-altropyranoside crystal structure
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Chiral Phosphine Ligands Derived fro m Sugars .14 . Crystal Structure of Diphenyl( m ethyl4’,6’-O-benzylidene-3’-deoxy-α- D-altropyranoside-3-)phosphine Oxide
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作者 施继成 洪茂椿 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1999年第5期344-347,共4页
The crystal structure of the title compound, C 26 H 27 O 6P, has been determined by single crystal X ray diffraction analysis. The crystal is orthorhombic with space group P2 12 12 1, a=6.154(4), b=17.199(8), c=22.180... The crystal structure of the title compound, C 26 H 27 O 6P, has been determined by single crystal X ray diffraction analysis. The crystal is orthorhombic with space group P2 12 12 1, a=6.154(4), b=17.199(8), c=22.180(3) , V=2347.6 3, D c=1.32 g/cm 3, F(000)=984, μ=1.5 cm -1 , Z =4, and final R =0.075 and R w =0.080 for 1417 reflections (I≥3σ(I)) . The X ray diffraction analysis revealed that the structure of the title compound s similar to that of its parent phosphine and the pyranose and 4, 6 O benzylidene rings remain distorted chair conformations. 展开更多
关键词 chiral phosphine oxide α D altropyranoside crystal structure
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Synthesis of 3-O-Benzoyl-1 ,2-O-isopropylidene-a-D-allofuranose and Its Dimesylated Derivative
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作者 张卫红 孟祥启 +1 位作者 冯亚青 刘云华 《Transactions of Tianjin University》 EI CAS 2005年第6期440-445,共6页
Diisopropylidenated α-D-glucofuranose (1) was oxidated with CrO3-pyridine complex. Oxidated product and its hydrate were separated and were reduced together to synthesize diisopropylidenated α-D-allofuranose ( 3... Diisopropylidenated α-D-glucofuranose (1) was oxidated with CrO3-pyridine complex. Oxidated product and its hydrate were separated and were reduced together to synthesize diisopropylidenated α-D-allofuranose ( 3). The yield of 3 increased by 8% than that with only oxidated product as reduction substrate. Benzoylated derivative of 3 was selectively nydrolyzed and dimesylated to synthesize 3-O-benzoyl-1 .2- O- isopropylidene-α-D-allofuranose ( 5 ) and its dimesylated derivative respectively. The overall yield of 5 from 1 was 36%. Each step and final products were analyzed by ^1H-NMR spectra and other methods. The experiments showed that the influence of acetic acid concentration on selective hydrolysis was obvious. The hydrolysis yield was 81.8%. Oxidation. reduction and other procedures were practical and had application potential. 展开更多
关键词 3-O-benzoyl-1. 2-O-isopropylidene-α-D-allofuranose OXIDATION reduction - selective hydrolysis dimesylation
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Plating densities, alpha-difluoromethylornithine effects and time dependence on the proliferation of IEC-6 cells 被引量:1
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作者 张予理 陈蔚文 《Chinese Medical Journal》 SCIE CAS CSCD 2002年第4期518-520,共3页
OBJECTIVE: To characterize the role of plating densities and alpha-difluoromethylornithine (DFMO) on the proliferation of IEC-6 cells in vitro. METHODS: IEC-6 cells were seeded in 96-well microplates at various densit... OBJECTIVE: To characterize the role of plating densities and alpha-difluoromethylornithine (DFMO) on the proliferation of IEC-6 cells in vitro. METHODS: IEC-6 cells were seeded in 96-well microplates at various densities in the presence or absence of DFMO. Cells were counted and their proliferative capability was monitored Days 1 to 7 with MTT assay at an optical density of 570 nm. RESULTS: There was a positive relationship between cell number and OD value (r = 0.954, P 0.5 x 10(4) cells/well) inhibited the growth of cells on Day 2. When the density reaches 4 x 10(4) cells/well, the OD value increased gradually and reached a peak on Day 5. After that, the OD value began to fall. The growth of IEC-6 cells was limited at a low density (0.2 x 10(4) cells/well) on Day 4. DFMO caused a complete inhibition of proliferation of IEC-6 cells on Days 1 to 3. CONCLUSION: Proliferation of IEC-6 cells is related to plating density and incubation time. It is inhibited by DFMO, but is reversible when the incubation time is prolonged. 展开更多
关键词 Animals Antineoplastic Agents Cell Count Cell Division Cell Line EFLORNITHINE Research Support Non-U.S. Gov't Time Factors
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Plating densities, alpha-difluoromethylornithine effects and time dependence on the proliferation of IEC-6 cells
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作者 张子理 陈蔚文 《Chinese Medical Journal》 SCIE CAS CSCD 2002年第4期38-40,148,共4页
To characterize the role of plating densities and alpha difluoromethylornithine (DFMO) on the proliferation of IEC 6 cells in vitro Methods IEC 6 cells were seeded in 96 well microplates at various densitie... To characterize the role of plating densities and alpha difluoromethylornithine (DFMO) on the proliferation of IEC 6 cells in vitro Methods IEC 6 cells were seeded in 96 well microplates at various densities in the pre sence or absence of DFMO Cells were counted and their proliferative capabilit y was monitored Days 1 to 7 with MTT assay at an optical density of 570?nm Results There was a positive relationship between cell number and OD value ( r =0 954 , P 【0 01) Higher plating densities (】0 5×10 4 cells/well) inhibited the growth of cells on Day 2 When the density reaches 4×10 4 cells/well, the O D value increased gradually and reached a peak on Day 5 After that, the OD va lue began to fall The growth of IEC 6 cells was limited at a low density (0 2×10 4 cells/well) on Day 4 DFMO caused a complete inhibition of proliferati on of IEC 6 cells on Days 1 to 3 Conclusion Proliferation of IEC 6 cells is related to plating density and incubation time It is inhibited by DFMO, but is reversible when the incubation time is prolon ged 展开更多
关键词 IEC 6 cell line · proliferation · MTT assay · alpha difluoromethylornithine
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