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Synthesis of Methylated β-Cyclodextrins Derived Optically Active Poly(N-diphenylmethyl maleimide)
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作者 Wei Hong LIU Yong Ming CHEN Chuan Fu CHEN and Fu XI (Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 ) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第3期215-218,共4页
The methylated β-cyclodextrins derived optically active polymers are firs synthesized through asymmetric polymerization of N-diphenylmethyl maleimide with lithium salt of heptakis(2,6-O-dimethyl) β-cyclodextrin (DM-... The methylated β-cyclodextrins derived optically active polymers are firs synthesized through asymmetric polymerization of N-diphenylmethyl maleimide with lithium salt of heptakis(2,6-O-dimethyl) β-cyclodextrin (DM-β-CD) as an initiator. The resulting polymers show negative specific rotation which is opposite in sign to that of DM-β-CD. The asymmetric induction is further confirmed by circular dichroism. The structure is characterized by IR and NMR spectroscopies 展开更多
关键词 Cyclodextrins Derived Optically Active Poly Li CHEN N-diphenylmethyl maleimide Synthesis of methylated
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Study on the inclusion interaction of methylated-β-cyclodextrins with albendazole by spectrofluorimetry and its application 被引量:1
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作者 Guo Yan Zhao Hao Wu Sheng Li Dong Li Ming Du 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第8期951-954,共4页
The inclusion interaction between three types of methylated-β-cyclodextrins (Me-β-CDs) and albendazole (ABZ) was studied by spectrofluorimetry. The result showed that Me-β-CDs reacted with ABZ to form an inclus... The inclusion interaction between three types of methylated-β-cyclodextrins (Me-β-CDs) and albendazole (ABZ) was studied by spectrofluorimetry. The result showed that Me-β-CDs reacted with ABZ to form an inclusion complex, 1: 1 stoichiometry for Me- β-CDs-ABZ complex was established and its association constant have been determined from fluorescence data by Benesi- Hildebrand's method (double reciprocal plots). It was noted that 2,6-DM-β-CD exhibited stronger binding ability than other Me-β- CDs. Based on the significant enhancement of fluorescence intensity of inclusion complex, a simple and highly sensitive fluorimetric method is proposed for the determination of ABZ in the presence of 2,6-DM-β-CD. The proposed method was successfully applied to the determination of ABZ in tablets and human urine. 展开更多
关键词 methylated-cyclodextrins ALBENDAZOLE SPECTROFLUORIMETRY
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Morphological Evolution of Self-Assembled Sodium Dodecyl Sulfate/Dodecyltrimethylammonium Bromide@Epoxy-β-Cyclodextrin Supramolecular Aggregates Induced by Temperature
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作者 Qingran Meng Wenwen Xu +2 位作者 Zuobing Xiao Qinfei Ke Xingran Kou 《Journal of Renewable Materials》 EI CAS 2024年第4期629-641,共13页
Bio-based cyclodextrins(CDs)are a common research object in supramolecular chemistry.The special cavity structure of CDs can form supramolecular self-assemblies such as vesicles and microcrystals through weak interact... Bio-based cyclodextrins(CDs)are a common research object in supramolecular chemistry.The special cavity structure of CDs can form supramolecular self-assemblies such as vesicles and microcrystals through weak interaction with guest molecules.The different forms of supramolecular self-assemblies can be transformed into each other under certain conditions.The regulation of supramolecular self-assembly is not only helpful to understand the self-assembly principle,but also beneficial to its application.In the present study,the self-assembly behavior of epoxy-β-cyclodextrin(EP-β-CD)and mixed anionic and cationic surfactant system(sodium dodecyl sulfate/dodecyltrimethylammonium bromide,SDS/DTAB)in aqueous solution was studied.Morphological and particle size characterization found that the SDS/DTAB@EP-β-CD complex,as the basic building unit,self-assembled into worm-like micelles at lower temperatures and vesicles at higher temperatures.Nuclear magnetic resonance(NMR)and Fourier transform infrared spectroscopy(FT-IR)analysis revealed that the driving force for the formation of vesicles and worm-like micelles was the hydrogen bonds between EP-β-CD molecules,while water molecules played an important role in promoting vesicle formation between SDS/DTAB@EP-β-CD units.Herein,the mechanism of the morphologic transformation of SDS/DTAB@EP-β-CD supramolecular aggregates induced by temperature was elucidated by exploring the self-assembly process,which may provide an excellent basis for the development of delivery carriers. 展开更多
关键词 Epoxy-β-cyclodextrin SDS/DTAB SELF-ASSEMBLY TEMPERATURE morphological evolution
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Salsolinol as an RNA m~6A methylation inducer mediates dopaminergic neuronal death by regulating YAP1 and autophagy
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作者 Jianan Wang Yuanyuan Ran +5 位作者 Zihan Li Tianyuan Zhao Fangfang Zhang Juan Wang Zongjian Liu Xuechai Chen 《Neural Regeneration Research》 SCIE CAS 2025年第3期887-899,共13页
Salsolinol(1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline,Sal)is a catechol isoquinoline that causes neurotoxicity and shares structural similarity with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,an environme... Salsolinol(1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline,Sal)is a catechol isoquinoline that causes neurotoxicity and shares structural similarity with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,an environmental toxin that causes Parkinson's disease.However,the mechanism by which Sal mediates dopaminergic neuronal death remains unclear.In this study,we found that Sal significantly enhanced the global level of N~6-methyladenosine(m~6A)RNA methylation in PC12 cells,mainly by inducing the downregulation of the expression of m~6A demethylases fat mass and obesity-associated protein(FTO)and alk B homolog 5(ALKBH5).RNA sequencing analysis showed that Sal downregulated the Hippo signaling pathway.The m~6A reader YTH domain-containing family protein 2(YTHDF2)promoted the degradation of m~6A-containing Yes-associated protein 1(YAP1)mRNA,which is a downstream key effector in the Hippo signaling pathway.Additionally,downregulation of YAP1 promoted autophagy,indicating that the mutual regulation between YAP1 and autophagy can lead to neurotoxicity.These findings reveal the role of Sal on m~6A RNA methylation and suggest that Sal may act as an RNA methylation inducer mediating dopaminergic neuronal death through YAP1 and autophagy.Our results provide greater insights into the neurotoxic effects of catechol isoquinolines compared with other studies and may be a reference for assessing the involvement of RNA methylation in the pathogenesis of Parkinson's disease. 展开更多
关键词 ALKBH5 AUTOPHAGY FTO Hippo pathway m~6A Parkinson's disease RNA methylation SALSOLINOL YAP1 YTHDF2
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Characterization of microenvironmental polarity of methylated β-cyclodextrin with fluorescent probe method
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《Chinese Science Bulletin》 SCIE CAS 1998年第3期263-264,共2页
关键词 cyclodextrin with fluorescent probe method Characterization of microenvironmental polarity of methylated
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Clinical value of preoperative methylated septin 9 in Chinese colorectal cancer patients 被引量:19
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作者 Xue Yang Zhi-Jie Xu +9 位作者 Xi Chen Shuang-Shuang Zeng Long Qian Jie Wei Mei Peng Xiang Wang Wan-Li Liu Hong-Ying Ma Zhi-Cheng Gong Yuan-Liang Yan 《World Journal of Gastroenterology》 SCIE CAS 2019年第17期2099-2109,共11页
BACKGROUND The methylated septin 9(mSEPT9) assay was the first blood-based test approved by the United States Food and Drug Administration as a colorectal screening test.However, the diagnostic and prognostic role of ... BACKGROUND The methylated septin 9(mSEPT9) assay was the first blood-based test approved by the United States Food and Drug Administration as a colorectal screening test.However, the diagnostic and prognostic role of preoperative mSEPT9 for colorectal cancer(CRC) in Chinese patients is still unknown.AIM To improve the understanding of diagnostic and prognostic factors, serum m SEPT9 was detected in Chinese CRC patients.METHODS A retrospective analysis of 354 cases, of which 300 had CRC and 54 were normal,was performed in China. Patients' characteristics, treatments, and laboratory data, including age, the date of surgery, Union for International Cancer Control(UICC) stages, distant metastasis(M), and so on, were collected. Methylation levels of SEPT9 were quantified by quantitative, methylation-specific polymerase chain reaction before surgery. In addition, the effects of mSEPT9 on the occurrence and prognosis of 330 CRC cases from The Cancer Genome Atlas(TCGA) database were evaluated using bioinformatics analyses. Potential prognostic factors for overall survival(OS) and progression-free survival(PFS)were evaluated by Kaplan-Meier univariate analysis.RESULTSIn Chinese CRC patients, positive mSEPT9 was strongly associated with advanced UICC stages, deeper invasion by the primary tumor, and more distant metastasis. Methylation levels of SEPT9 were stage-dependent and showed a stepwise increase in UICC stages(I–IV), primary tumor categories(T1–T4),regional node categories(N0–N2), and distant metastasis categories(M0–M1).The patients with positive mSEPT9 showed a tendency toward lower PFS. After analyzing TCGA clinical data, the high mSEPT9 group was found to be obviously correlated only with more distant metastasis. The patients with high mSEPT9 levels showed a tendency toward lower OS. Besides, nine meaningful mSEPT9 sites were found to provide guidance for the follow-up studies.CONCLUSION MSEPT9 analysis may add valuable information to current tumor staging. Serum m SEPT9 in Chinese CRC patients appears to offer promising novel prognostic markers and might be considered for monitoring CRC recurrence. 展开更多
关键词 methylated SEPTIN 9 methylated COLORECTAL cancer Diagnosis PROGNOSIS
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Bioinformatics analysis of aberrantly methylated-differentially expressed genes and pathways in hepatocellular carcinoma 被引量:7
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作者 Liang Sang Xue-Mei Wang +1 位作者 Dong-Yang Xu Wen-jing Zhao 《World Journal of Gastroenterology》 SCIE CAS 2018年第24期2605-2616,共12页
AIM To discover methylated-differentially expressed genes(MDEGs) in hepatocellular carcinoma(HCC) and to explore relevant hub genes and potential pathways. METHODS The data of expression profiling GSE25097 and methyla... AIM To discover methylated-differentially expressed genes(MDEGs) in hepatocellular carcinoma(HCC) and to explore relevant hub genes and potential pathways. METHODS The data of expression profiling GSE25097 and methylation profiling GSE57956 were gained from GEO Datasets. We analyzed the differentially methylated genes and differentially expressed genes online using GEO2 R. Functional and enrichment analyses of MDEGs were conducted using the DAVID database. A protein-protein interaction(PPI) network was performed by STRING and then visualized in Cytoscape. Hub genes were ranked by cytoH ubba, and a module analysis of the PPI network was conducted by MCODE in Cytoscape software. RESULTS In total, we categorized 266 genes as hypermethylated, lowly expressed genes(Hyper-LGs) referring to endogenous and hormone stimulus, cell surface receptor linked signal transduction and behavior. In addition, 161 genes were labelled as hypomethylated, highly expressed genes(Hypo-HGs) referring to DNA replication and metabolic process, cell cycle and division. Pathway analysis illustrated that Hyper-LGs were enriched in cancer, Wnt, and chemokine signalling pathways, while Hypo-HGs were related to cell cycle and steroid hormone biosynthesis pathways. Based on PPI networks, PTGS2, PIK3 CD, CXCL1, ESR1, and MMP2 were identified as hub genes for Hyper-LGs, and CDC45, DTL, AURKB, CDKN3, MCM2, and MCM10 were hub genes for Hypo-HGs by combining six ranked methods of cytoH ubba. CONCLUSION In the study, we disclose numerous novel genetic and epigenetic regulations and offer a vital molecular groundwork to understand the pathogenesis of HCC. Hub genes, including PTGS2, PIK3 CD, CXCL1, ESR1, MMP2, CDC45, DTL, AURKB, CDKN3, MCM2, and MCM10, can be used as biomarkers based on aberrant methylation for the accurate diagnosis and treatment of HCC. 展开更多
关键词 HEPATOCELLULAR CARCINOMA methylATION Gene expression BIOINFORMATICS analysis
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A differentially methylated region of the DAZ1 gene in spermatic and somatic cells 被引量:3
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作者 Zuo-Xiang Li Xu Ma Zhao-Hui Wang 《Asian Journal of Andrology》 SCIE CAS CSCD 2006年第1期61-67,共7页
Aim: To investigate the methylation status of the deleted in azoospermia 1(DAZ1) gene promoter region in different cell types. Methods: Using CpG island Searcher software, a CpG island was found in the promoter re... Aim: To investigate the methylation status of the deleted in azoospermia 1(DAZ1) gene promoter region in different cell types. Methods: Using CpG island Searcher software, a CpG island was found in the promoter region of the DAZ1 gene. The methylation status of this region was analyzed in sperm and leukocytes by bisulfited sequencing. Results: The methylation status of the CpG island in the DAZ1 gene promoter region differed in leukocytes and sperm: it was methylated in leukocytes, but unmethylated in sperm. Conclusion: A differentially methylated region of the DAZ1 gene exists in spermatic and somatic cells, suggesting that methylation of this region may regulate DAZ1 gene expression in different tissues. (Asian J Androl 2006 Jan; 8:61-67 ) 展开更多
关键词 DAZ1 gene DNA methylation CpG island methylated region SPERMATOGENESIS
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Cell-free plasma hypermethylated CASZ1, CDH13 and ING2 are promising biomarkers of esophageal cancer 被引量:6
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作者 Huanqiang Wang Congying Yang +7 位作者 Siyuan Wang Tian Wang Jingling Han Kai Wei Fucun Liu Jida Xu Xianzhen Peng Jianming Wang 《The Journal of Biomedical Research》 CAS CSCD 2018年第6期424-433,共10页
Identifying sensitive and specific biomarkers for early detection of cancer is immensely imperative for early diagnosis and treatment and better clinical outcome of cancer patients. This study aimed to construct a spe... Identifying sensitive and specific biomarkers for early detection of cancer is immensely imperative for early diagnosis and treatment and better clinical outcome of cancer patients. This study aimed to construct a specific DNA methylation pattern of cancer suppressor genes and explore the feasibility of applying cell-free DNA based methylation as a biomarker for early diagnosis of esophageal squamous cell carcinoma(ESCC). We recruited early stage ESCC patients from Yangzhong County, China. The Illumina Infinium 450 K Methylation BeadChip was used to construct a genome-wide DNA methylation profile. Then, differentiated genes were selected for the validation study using the Sequenom MassARRAY platform. The frequency of methylation was compared between cancer tissues, matched cell-free DNAs and normal controls. The specific methylation profiles were constructed, and the sensitivity and specificity were calculated. Seven CG sites in three genes CASZ1, CDH13 and ING2 were significantly hypermethylated in ESCC as compared with normal controls. A significant correlation was found between the methylation of DNA extracted from cancer tissues and matched plasma cell-free DNA, either for individual CG site or for cumulative methylation analysis. The sensitivity and specificity reached 100% at an appropriate cut-point using these specific methylation biomarkers. This study revealed that aberrant DNA methylation is a promising biomarker for molecular diagnosis of esophageal cancer. Hypermethylation of CASZ1,CDH13 and ING2 detected in plasma cell-free DNA can be applied as a potential noninvasive biomarker for diagnosis of esophageal cancer. 展开更多
关键词 esophageal neoplasms DNA methylation epigenesist biological markers tumor suppressor
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Hypermethylated SFRP2 gene in fecal DNA is a high potential biomarker for colorectal cancer noninvasive screening 被引量:25
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作者 Dao-RongWang Dong Tang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第4期524-531,共8页
AIM: To investigate the feasibility of detecting hypermethylated secreted frizzled-related protein 2 (SFRP2) gene in fecal DNA as a non-invasive screening tool for colorectal cancer (CRC). METHODS: Fluorescence-based ... AIM: To investigate the feasibility of detecting hypermethylated secreted frizzled-related protein 2 (SFRP2) gene in fecal DNA as a non-invasive screening tool for colorectal cancer (CRC). METHODS: Fluorescence-based real-time PCR assay (MethyLight) was performed to analyze SFRP2 gene promoter methylation status in a blinded fashion in tumor tissues and in stool samples taken from 69 CRC patients preoperatively and at the 9th postoperative day,34 patients with adenoma ≥ 1 cm,26 with hyperplastic polyp,and 30 endoscopically normal subjects. Simultaneously the relationship between hypermethylation of SFRP2 gene and clinicopathological features was analyzed. RESULTS: SFRP2 gene was hypermethylated in 91.3% (63/69) CRC,79.4% (27/34) and 53.8% (14/26) adenoma and hyperplastic polyp tissues,and in 87.0% (60/69),61.8% (21/34) and 42.3% (11/26) of corresponding fecal samples,respectively. In contrast,no methylated SFRP2 gene was detected in mucosal tissues of normal controls,while two cases of matched fecal samples from normal controls were detected with hypermethylated SFRP2. A significant decrease (P < 0.001) in the rate of hypermethylated SFRP2 gene was detected in the postoperative (8.7%,6/69) fecal samples as compared with the preoperative fecal samples (87%,60/69) of CRC patients. Moreover,no significant associations were observed between SFRP2 hypermethylation and clinicopathological features including sex,age,tumor stage,site,lymph node status and histological grade,etc. CONCLUSION: Hypermethylation of SFRP2 gene in fecal DNA is a novel molecular biomarker of CRC and carries a high potential for the remote detection of CRC and premalignant lesions as noninvasive screening method. 展开更多
关键词 Colorectal cancer Secreted frizzled-relatedprotein 2 FECES methylation SCREENING
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hsa-mir-183 is frequently methylated and related to poor survival in human hepatocellular carcinoma 被引量:3
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作者 Sumadi Lukman Anwar Till Krech +7 位作者 Britta Hasemeier Elisa Schipper Nora Schweitzer Arndt Vogel Hans Kreipe Reena Buurman Britta Skawran Ulrich Lehmann 《World Journal of Gastroenterology》 SCIE CAS 2017年第9期1568-1575,共8页
To screen clinically relevant microRNAs (miRNAs) silenced by DNA methylation in human hepatocellular carcinoma (HCC).METHODSKnockdown of DNA methyltransferases (DNMTs) using siRNAs and miRNA profiling in HCC cell line... To screen clinically relevant microRNAs (miRNAs) silenced by DNA methylation in human hepatocellular carcinoma (HCC).METHODSKnockdown of DNA methyltransferases (DNMTs) using siRNAs and miRNA profiling in HCC cell lines were performed to identify DNA hypermethylation-mediated miRNA downregulation. Confirmation using individual quantitative real-time PCR (qRT-PCR) assays was then performed followed by DNA methylation quantification at the promoter of the miRNA genes. Quantification of DNA methylation and miRNA expression was then performed in primary HCC tumor samples and related with clinicopathological variables.RESULTSmiRNA profiling after DNMT knockdown in HCC cell lines revealed upregulation of miR-23, miR-25 and miR-183. After qRT-PCR confirmation and CpG island methylation quantification of these miRNAs in cell lines, further analysis in primary HCC specimens showed that hsa-miR-183 is hypermethylated in 30% of HCC (n = 40). Expression of mature miR-183 showed an inverse correlation with DNA methylation levels. In HCC cells, DNMT knockdown and 5-aza-2’-deoxycytidine treatment reduced methylation and stimulated expression of miR-183. In HCC patients, hypermethylation at hsa-miR-183 promoter significantly correlates with poor survival (log-rank test P = 0.03). DNA methylation analysis in healthy liver, benign liver tumors (hepatocellular adenoma and focal nodular hyperplasia) and their corresponding adjacent tissues showed absence of hypermethylation supporting the notion that aberrant methylation at hsa-miR-183 is specific for the malignant transformation of hepatocytes.CONCLUSIONOur data indicate that hypermethylation of hsa-miR-183 is a frequent event in HCC and potentially useful as a novel surrogate diagnostic and prognostic marker. 展开更多
关键词 hsa-miR-183 DNA methylation DNMT knockdown microRNA microarray
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Mechanism and Kinetics of Thermal Dissociation of Inclusion Complex of β-Cyclodextrin and 1-Methylcyclopropene 被引量:5
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作者 Yi He Ting Sun 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第1期89-92,共4页
The inclusion-complex of CD-MCP (β-cyclodextrin (β-CD) including 1-methylcyclopropene (1-MCP)) was prepared and characterized. Basing on programmed-heating procedure and weight-temperature analysis, as well as... The inclusion-complex of CD-MCP (β-cyclodextrin (β-CD) including 1-methylcyclopropene (1-MCP)) was prepared and characterized. Basing on programmed-heating procedure and weight-temperature analysis, as well as the application of Satava-Sestak's, Ozawa's and Kissinger's methods, the mechanism and kinetics of thermal dissociation of this inclusion complex were studied. An additional mass loss is found at 170-180℃. The mechanism of thermal dissociation of CD-MCP is dominated by a one-dimensional random nucleation and subsequent growth process (A2/3). The activation energy Es and the pre-exponential factor AS for the process are 102.14 kJ/mol and 3.63×10^10s^-1, respectively. This ES value shows that there is no strong chemical intere, ctions between β-CD and 1-MC;P, 展开更多
关键词 1-methylcyclopropene Β-cyclodextrin Inclusion complex KINETICS MECHANISM Thermal dissociation
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Procaine Inhibiting Human Bladder Cancer Cell Proliferation by Inducing Apoptosis and Demethylating APAF1 CpG Island Hypermethylated 被引量:3
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作者 SUN Ran CHANG Li-ping +2 位作者 WANG Kai-chen SUN Hong-yan CONG Xian-ling 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第6期1017-1021,共5页
Studies have shown that aberrant DNA methylation of apoptotic protease activating factor-1(APAF1) is an important epigenetic mechanism of gene regulation in the progression of bladder cancer.In this article,we have ... Studies have shown that aberrant DNA methylation of apoptotic protease activating factor-1(APAF1) is an important epigenetic mechanism of gene regulation in the progression of bladder cancer.In this article,we have proved that procaine,an inhibitor of DNA methyltransferases,could inhibit the proliferation of T24 and 5637 human bladder cancer cells by inducing their apoptosis.The mechanism studies reveal that procaine could induce demethylation of APAF1 gene in T24 or 5637 cells,subsequently activating caspase-3/9.It was also shown that the serum soluble fas ligand(sFasL) was activated,and the expression of matrix metallopeptidase 9(MMP-9) was down-regulated.Procaine seems to induce cell death by different pathways,and it might be used as a potential agent for bladder cancer treatment. 展开更多
关键词 Bladder cancer cell EPIGENETICS DNA methylation Apoptotic protease activating factor-1(APAF1) PROCAINE
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Triple-transforming gel prepared byβ-cyclodextrin,diphenylamine and lithium chloride in N,N-dimethylacetamide 被引量:3
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作者 Yuan Yuan Li Wen Jing Zhao Hua Cheng Zhang Tao Sun Wei An Fei Fei Xin Ai You Hao 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第10期1251-1254,共4页
This paper describes a triple-transforming gel system (gel-sol-gel') for the first time, which is a thermo-responsive and multi- component organogel prepared by β-cyclodextrin (β-CD), diphenylamine (DPA) and ... This paper describes a triple-transforming gel system (gel-sol-gel') for the first time, which is a thermo-responsive and multi- component organogel prepared by β-cyclodextrin (β-CD), diphenylamine (DPA) and lithium chloride (LiCl) in N,N-dimethyla- cetamide (DMAC) in a suitable proportion based on the supramolecular interactions. In the triple-transfomaing gel system, a gel (gel A) could be formed by β-CD, DPA and LiCl in DMAC at room temperature based on stirring, then the gel could transform into a clear solution based on heating, and then the other gel (gel B) can be formed at a relatively high temperature (Tget, the gelation temperature by heating). The two gel states in the triple-transforming gel system have different microstructures. This gel system was characterized by OM, SEM, IR and theology. 展开更多
关键词 GEL Triple-transforming Β-cyclodextrin Lithium N N-DImethylACETAMIDE
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Kaiso mainly locates in the nucleus in vivo and binds to methylated,but not hydroxymethylated DNA 被引量:1
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作者 Sisi Qin Baozhen Zhang +3 位作者 Wei Tian Liankun Gu Zheming Lu Dajun Deng 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2015年第2期148-155,共8页
Objective: Kaiso is upregulated in many cancers and proposed to bind with both methylated- and unmethylated-DNA in the nucleus as a transcriptional repressor. The objective is to define its subcellnlar localization i... Objective: Kaiso is upregulated in many cancers and proposed to bind with both methylated- and unmethylated-DNA in the nucleus as a transcriptional repressor. The objective is to define its subcellnlar localization in vivo and exact binding DNA sequences in cells. Methods: Compartmentalization of exogenous Kaiso in cells was tracked with enhanced green fluorescence protein (EGFP) tag. The endogenous Kaiso expression in gastric carcinoma tissue was examined with immunohistochemical staining. Kaiso-DNA binding was tested using electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation assay (CHIP). Results: Kaiso mainly localized in the nucleus of cancer and stromal cells in vivo, but remained in the cytoplasm of cultured cells. Most importantly, nuclear Kaiso can bind with the methylated-CGCG- containing sequence in the CDKN2A promoter, but not with the hydroxymethylated-CGCG sequence in HCT116 cells. Conclusions: Kaiso locates mainly in the nucleus in vivo where it binds with the methylated-CGCG sequences, but does not bind with the hydroxymethylated-CGCG sequences. 展开更多
关键词 Kaiso COMPARTMENTALIZATION DNA binding methylATION HYDROXYmethylATION CDKN2A
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Special DNA Methylated Sites Between Haploid of Twin-Seedling and Its Hybrids in Rice(Oryza sativa) 被引量:1
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作者 Wu Shao-hua XUE Jing-jing +2 位作者 ZHANG Hong-yu Xu Pei-zhou Wu Xian-jun 《Rice science》 2012年第2期94-99,共6页
DNA methylation is one of the epigenetic phenomena which can be transferred to the offspring by cell division in the evolution of organisms. The epigenetic regulation accompanied by gene expression can be found direct... DNA methylation is one of the epigenetic phenomena which can be transferred to the offspring by cell division in the evolution of organisms. The epigenetic regulation accompanied by gene expression can be found directly in the phenotype of haploidy plants. DNA cytosine methylation at the 5'-CpCpGpG sites of haploid, Shuhui 527, Shuhui 363 and their hybrids was analyzed by methylation sensitive amplification polymorphism (MSAP) method. There were 765 DNA methylated sites detected and the methylation level was lower in hybrids than parents. Meanwhile, the different bands between hybrids and parents were analyzed and two types of methylated sites were detected, of which one inherited from haploid, and the other did not. The biological functions of genes related to methylated sites involved in cell structure, metabolize and response factor. Therefore, DNA methylated modifications can activate and silence the genes and play an important role in plant growth, development and evolution. 展开更多
关键词 twin-seedling rice HAPLOID methylation sensitive amplification polymorphism DNA methylation
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Combination analysis of hypermethylated SFRP1 and SFRP2 gene in fecal as a novel epigenetic biomarker panel for colorectal cancer screening 被引量:4
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作者 Dong Tang Daorong Wang Hongbo Li 《Journal of Nanjing Medical University》 2008年第2期96-101,共6页
Objective:To investigate the feasibility of the combination of detecting hypermethylated secreted frizzled-related protein 1 (SFRP1) and secreted frizzled-related protein 2(SFRP2) in feces as a panel of biomarker... Objective:To investigate the feasibility of the combination of detecting hypermethylated secreted frizzled-related protein 1 (SFRP1) and secreted frizzled-related protein 2(SFRP2) in feces as a panel of biomarkers for colorectal cancer(CRC) screening. Methods: Methylation-specific PCR(MSP) was performed to analyze methylation status of SFRP1 and SFRP2 in a blinded fashion in tumor tissues and in matched stool samples from 39 patients with primary CRC, 34 patients with adenomas, 17 patients with hyperplastic polyps and 20 endoscopically normal subjects as normal controls. Simultaneously we analyzed the correlation of hypermethylated SFRP1 and SFRP2 with the clinicopathological features of CRC. Results:Hypermethylated SFRP1 was detected in 92.3%, 76.5%, 47.1% of tissue samples and in 89.7%, 64.7%, 35.3% of matched fecal samples from CRC, adenoma and hyperplastic polyp, respectively. Hypermethylated SFRP2 was detected in 87.2%, 67.6%, 35.3% of tissue samples and in 82.1%, 55.9%, 29.4% of matched fecal samples from CRC, adenoma and hyperplastic polyp, respectively. Of these two genes, at least one hypermethylated was 94.9%, 82.4%, 52.9% in tissue samples and 92.3%,73.5%, 47.1% in matched fecal samples from CRC, adenoma and hyperplastic polyp, respectively. In contrast, no hypermethylated SFRP1 and SFRP2 were detected in mucosa tissues of normal controls, only 2 cases of fecal samples was detected with hypermethylated SFRP1 and another 1 case was detected with hypermethylated SFRP2. Moreover, no significant associations were observed between hypermethylated SFRP1,SFRP2 and clinicopathological features of CRC. Conclusion: Hypermethylation of SFRP1 and SFRP2 in feces are novel epigenetic biomarkers of CRC and carded high potential for the remote detection of CRC as non-invasive screening method, and combined analysis of hypermethylated SFRP1 and SFRP2 in fecal could further increase the detection rate of CRC and premalignant lesions. 展开更多
关键词 Secreted frizzled-related protein I(SFRP1) secreted frizzled-related protein 2(SFRP2) methylation colorectal cancer feces
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XAF1 is frequently methylated in human esophageal cancer 被引量:10
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作者 Xiang-Yu Chen Qiao-Yu He Ming-Zhou Guo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第22期2844-2849,共6页
AIM: To explore epigenetic changes in the gene encod- ing X chromosome-linked inhibitor of apoptosis-associ- ated factor 1 (XAF1) during esophageal carcinogenesis. METHODS: Methylation status of XAF1 was detected ... AIM: To explore epigenetic changes in the gene encod- ing X chromosome-linked inhibitor of apoptosis-associ- ated factor 1 (XAF1) during esophageal carcinogenesis. METHODS: Methylation status of XAF1 was detected by methylation-specific polymerase chain reaction (MSP) in four esophageal cancer cell lines (KYSE30, KYSE70, BICl and partially methylated in TE3 cell lines), nine cases of normal mucosa, 72 cases of pri- mary esophageal cancer and matched adjacent tissue. XAF1 expression was examined by semi-quantitative reverse transcriptional polymerase chain reaction and Western blotting before and after treatment with 5-aza- deoxycytidine (5-aza-dc), a demethylating agent. To investigate the correlation of XAF1 expression and methylation status in primary esophageal cancer, immu- nohistochemistry for XAF1 expression was performed in 32 cases of esophageal cancer and matched adjacent tissue. The association of methylation status and clini-copathological data was analyzed by logistic regression. RESULTS: MSP results were as follows: loss of XAF1 expression was found in three of four esophageal cell lines with promoter region hypermethylation (com- pletely methylated in KYSE30, KYSE70 and BIC1 cell lines and partially in TE3 cells); all nine cases of normal esophageal mucosa were unmethylated; and 54/72 (75.00%) samples from patients with esophageal can- cer were methylated, and 25/72 (34.70%) matched adjacent tissues were methylated (75.00% vs 34,70%, z2 = 23.5840, P = 0.000). mRNA level of XAF1 mea- sured with semi-quantitative reverse transcription poly- merase chain reaction was detectable only in TE3 cells, and no expression was detected in KYSE30, KYSE70 or BIC1 cells. Protein expression was not observed in KYSE30 cells by Western blotting before treatment with 5-aza-dc. After treatment, mRNA level of XAF1 was detectable in KYSE30, KYSE70 and BIC1 cells. Protein expression was detected in KYSE30 after treatment with 5-aza-dc. Immunohistochemistry was performed on 32 cases of esophageal cancer and adjacent tissue, and demonstrated XAF1 in the nucleus and cytoplasm. XAF1 staining was found in 20/32 samples of adjacent normal tissue but was present in only 8/32 samples of esophageal cancer tissue (Z2= 9.143, P = 0.002). XAF1 expression was decreased in cancer samples compared with adjacent tissues. In 32 cases of esophageal can- cer, 24/32 samples were methylated, and 8/32 esopha- geal cancer tissues were unmethylated. XAF1 staining was found in 6/8 samples of unmethylated esophageal cancer and 2/24 samples of methylated esophageal cancer tissue. XAF1 staining was inversely correlated with XAF1 promoter region methylation (Fisher's exact test, P = 0.004). Regarding methylation status and clinicopathological data, no significant differences were found in sex, age, tumor size, tumor stage, or metas- tasis with respect to methylation of XAF1 for the 72 tis- sue samples from patients with esophageal cancer. CONCLUSION: XAF1 is frequently methylated in eso- phageal cancer, and XAF1 expression is regulated by promoter region hypermethylation. 展开更多
关键词 X chromosome-linked inhibitor of apoptosis-associated factor 1 Esophageal cancer methylATION methylation-specific polymerase chain reaction Semi-quantitative reverse transcriptional polymerase chainreaction
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Preparation and Evaluation of Insulin-loaded Nanoparticles based on Hydroxypropyl-β-cyclodextrin Modified Carboxymethyl Chitosan for Oral Delivery 被引量:3
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作者 宋豪源 马晓玲 +7 位作者 XIONG Fuliang HONG Hui LI Chunfu LI Lianghong WU Shanshan ZHANG Xueqiong 张娟 胡建华 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第6期1394-1400,共7页
Novel insulin-loaded nanoparticles based on hydroxypropyl-β-cyclodextrin modified carboxymethyl chitosan(CMC-HP-β-CD) were prepared to improve the oral bioavailability of insulin. The CMC-HP-β-CD was characterize... Novel insulin-loaded nanoparticles based on hydroxypropyl-β-cyclodextrin modified carboxymethyl chitosan(CMC-HP-β-CD) were prepared to improve the oral bioavailability of insulin. The CMC-HP-β-CD was characterized by FT-IR spectroscopy and 1H-NMR spectra. The insulin-loaded nanoparticles were prepared through crosslinking with calcium ions, and the morphology and size of the prepared nanoparticles were characterized by transmission electron microscopy(TEM) and dynamic light scattering(DLS). Cumulative release in vitro study was performed respectively in simulated gastric medium fluid(SGF, p H=1.2), simulated intestinal fluid(SIF, p H=6.8) and simulated colonic fluid(SCF, p H=7.4). The encapsulation efficiency of insulin was up to 87.14 ± 4.32% through high-performance liquid chromatography(HPLC). Statistics indicated that only 15% of the encapsulated insulin was released from the CMC-HP-β-CD nanoparticles in 36 h in SGF, and about 50% of the insulin could be released from the nanoparticles in SIF, whereas more than 80% was released in SCF. In addition, the solution containing insulin nanoparticles could effectively reduce the blood glucose level of diabetic mice. The cytotoxicity test showed that the samples had no cytotoxicity. CMC-HP-β-CD nanoparticles are promising candidates as potential carriers in oral insulin delivery systems. 展开更多
关键词 carboxymethyl chitosan hydroxypropyl-β-cyclodextrin nanoparticles insulin oral delivery bioavailability cytotoxicity
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6-O-(Hydroxypropyltrimethylammonia)-β-cyclodextrin with Low Degree of Substitution: Convenient Preparation and its Application as a Chiral Selector in Capillary Electrophoresis 被引量:1
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作者 Ming Gang ZHAO Ai You HAO Jian LI Xiu Li LIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第3期407-410,共4页
A cationic cyclodextrin derivative 6-O-(hydroxypropyltrimethylammonia)-β-cyclodextrin (GTA-β-CD) with low degree of substitution was prepared through a convenient method in solid phase. The product could be used... A cationic cyclodextrin derivative 6-O-(hydroxypropyltrimethylammonia)-β-cyclodextrin (GTA-β-CD) with low degree of substitution was prepared through a convenient method in solid phase. The product could be used as a valuable chiral selector in the capillary electrophoresis (CE) separation of some acidic drug enantiomers such as naproxen, ofloxacin, ibuprofen and warfarin. 展开更多
关键词 6-O-(Hydroxypropyltrimethylammonia)-β-cyclodextrin capillary electrophoresis chiral selector.
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