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Sample records for active demethylation represent

  1. Active DNA demethylation by oxidation and repair

    Institute of Scientific and Technical Information of China (English)

    Zhizhong Gong; Jian-Kang Zhu

    2011-01-01

    DNA methylation and demethylation are increasingly recognized as important epigenetic factors in both plants and animals.DNA methylation,which is catalyzed by DNA methyltransferases (DNMTs),is a relatively stable and heritable modification that controls gene expression,cellular differentiation,genomic imprinting,paramutation,transposon movement,X-inactivation,and embryogenesis [1].The methylation of cytosine to 5-methylcytosine (5mC) is an important example of DNA modification in animals and plants.This highlight concerns DNA demethylation mechanisms in mammals and whether they are similar to that in plants.

  2. RUNX1 induces DNA replication independent of active DNA demethylation at SPI1 regulatory regions.

    Science.gov (United States)

    Goyal, Shubham; Suzuki, Takahiro; Li, Jing-Ru; Maeda, Shiori; Kishima, Mami; Nishimura, Hajime; Shimizu, Yuri; Suzuki, Harukazu

    2017-04-04

    SPI1 is an essential transcription factor (TF) for the hematopoietic lineage, in which its expression is tightly controlled through a -17-kb upstream regulatory region and a promoter region. Both regulatory regions are demethylated during hematopoietic development, although how the change of DNA methylation status is performed is still unknown. We found that the ectopic overexpression of RUNX1 (another key TF in hematopoiesis) in HEK-293T cells induces almost complete DNA demethylation at the -17-kb upstream regulatory region and partial but significant DNA demethylation at the proximal promoter region. This DNA demethylation occurred in mitomycin-C-treated nonproliferating cells at both regulatory regions, suggesting active DNA demethylation. Furthermore, ectopic RUNX1 expression induced significant endogenous SPI1 expression, although its expression level was much lower than that of natively SPI1-expressing monocyte cells. These results suggest the novel role of RUNX1 as an inducer of DNA demethylation at the SPI1 regulatory regions, although the mechanism of RUNX1-induced DNA demethylation remains to be explored.

  3. The Emerging Nexus of Active DNA Demethylation and Mitochondrial Oxidative Metabolism in Post-Mitotic Neurons

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    Huan Meng

    2014-12-01

    Full Text Available The variable patterns of DNA methylation in mammals have been linked to a number of physiological processes, including normal embryonic development and disease pathogenesis. Active removal of DNA methylation, which potentially regulates neuronal gene expression both globally and gene specifically, has been recently implicated in neuronal plasticity, learning and memory processes. Model pathways of active DNA demethylation involve ten-eleven translocation (TET methylcytosine dioxygenases that are dependent on oxidative metabolites. In addition, reactive oxygen species (ROS and oxidizing agents generate oxidative modifications of DNA bases that can be removed by base excision repair proteins. These potentially link the two processes of active DNA demethylation and mitochondrial oxidative metabolism in post-mitotic neurons. We review the current biochemical understanding of the DNA demethylation process and discuss its potential interaction with oxidative metabolism. We then summarise the emerging roles of both processes and their interaction in neural plasticity and memory formation and the pathophysiology of neurodegeneration. Finally, possible therapeutic approaches for neurodegenerative diseases are proposed, including reprogramming therapy by global DNA demethylation and mitohormesis therapy for locus-specific DNA demethylation in post-mitotic neurons.

  4. MAGEB2 is activated by promoter demethylation in head and neck squamous cell carcinoma.

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    Kavita M Pattani

    Full Text Available PURPOSE: Although promoter hypermethylation has been an accepted means of tumor suppressor gene inactivation, activation of otherwise normally repressed proto-oncogenes by promoter demethylation has been infrequently documented. EXPERIMENTAL DESIGN: In this study we performed an integrative, whole-genome analysis for discovery of epigenetically activated proto-oncogenes in head and neck cancer tumors. We used the 47K GeneChip U133 Plus 2.0 Affymetrix expression microarray platform to obtain re-expression data from 5-aza treated normal cell line and expression data from primary head and neck squamous cell carcinoma (HNSCC tumor tissues and normal mucosa tissues. We then investigated candidate genes by screening promoter regions for CpG islands and bisulfite sequencing followed by QUMSP and RT PCR for the best candidate genes. Finally, functional studies were performed on the top candidate gene. RESULTS: From the top 178 screened candidates 96 had CpG islands in their promoter region. Seven candidate genes showed promoter region methylation in normal mucosa samples and promoter demethylation in a small cohort of primary HNSCC tissues. We then studied the demethylation of the top 3 candidate genes in an expanded cohort of 76 HNSCC tissue samples and 17 normal mucosa samples. We identified MAGEB2 as having significant promoter demethylation in primary head and neck squamous cell carcinoma tissues. We then found significantly higher expression of MAGEB2 in tumors in a separate cohort of 73 primary HNSCC tissues and 31 normal tissues. Finally, we found that MAGEB2 has growth promoting effects on minimally transformed oral keratinocyte cell lines but not a definite effect on HNSCC cell lines. CONCLUSION: In conclusion, we identified MAGEB2 as activated by promoter demethylation in HNSCCand demonstrates growth promoting effects in a minimally transformed oral keratinocyte cell line. More studies are needed to evaluate MAGBE2's exact role in HNSCC.

  5. Overproduction of stomatal lineage cells in Arabidopsis mutants defective in active DNA demethylation.

    Science.gov (United States)

    Yamamuro, Chizuko; Miki, Daisuke; Zheng, Zhimin; Ma, Jun; Wang, Jing; Yang, Zhenbiao; Dong, Juan; Zhu, Jian-Kang

    2014-06-05

    DNA methylation is a reversible epigenetic mark regulating genome stability and function in many eukaryotes. In Arabidopsis, active DNA demethylation depends on the function of the ROS1 subfamily of genes that encode 5-methylcytosine DNA glycosylases/lyases. ROS1-mediated DNA demethylation plays a critical role in the regulation of transgenes, transposable elements and some endogenous genes; however, there have been no reports of clear developmental phenotypes in ros1 mutant plants. Here we report that, in the ros1 mutant, the promoter region of the peptide ligand gene EPF2 is hypermethylated, which greatly reduces EPF2 expression and thereby leads to a phenotype of overproduction of stomatal lineage cells. EPF2 gene expression in ros1 is restored and the defective epidermal cell patterning is suppressed by mutations in genes in the RNA-directed DNA methylation pathway. Our results show that active DNA demethylation combats the activity of RNA-directed DNA methylation to influence the initiation of stomatal lineage cells.

  6. Targeted DNA demethylation and activation of endogenous genes using programmable TALE-TET1 fusion proteins.

    Science.gov (United States)

    Maeder, Morgan L; Angstman, James F; Richardson, Marcy E; Linder, Samantha J; Cascio, Vincent M; Tsai, Shengdar Q; Ho, Quan H; Sander, Jeffry D; Reyon, Deepak; Bernstein, Bradley E; Costello, Joseph F; Wilkinson, Miles F; Joung, J Keith

    2013-12-01

    Genome-wide studies have defined cell type-specific patterns of DNA methylation that are important for regulating gene expression in both normal development and disease. However, determining the functional significance of specific methylation events remains challenging, owing to the lack of methods for removing such modifications in a targeted manner. Here we describe an approach for efficient targeted demethylation of specific CpGs in human cells using fusions of engineered transcription activator-like effector (TALE) repeat arrays and the TET1 hydroxylase catalytic domain. Using these TALE-TET1 fusions, we demonstrate that modification of critical methylated promoter CpG positions can lead to substantial increases in the expression of endogenous human genes. Our results delineate a strategy for understanding the functional significance of specific CpG methylation marks in the context of endogenous gene loci and validate programmable DNA demethylation reagents with potential utility for research and therapeutic applications.

  7. Impacts of Activated Carbon Amendment on Hg Methylation, Demethylation and Microbial Activity in Marsh Soils

    Science.gov (United States)

    Gilmour, C. C.; Ghosh, U.; Santillan, E. F. U.; Soren, A.; Bell, J. T.; Butera, D.; McBurney, A. W.; Brown, S.; Henry, E.; Vlassopoulos, D.

    2015-12-01

    In-situ sorbent amendments are a low-impact approach for remediation of contaminants in sediments, particular in habitats like wetlands that provide important ecosystem services. Laboratory microcosm trials (Gilmour et al. 2013) and early field trials show that activated carbon (AC) can effectively increase partitioning of both inorganic Hg and methylmercury to the solid phase. Sediment-water partitioning can serve as a proxy for Hg and MeHg bioavailability in soils. One consideration in using AC in remediation is its potential impact on organisms. For mercury, a critical consideration is the potential impact on net MeHg accumulation and bioavailability. In this study, we specifically evaluated the impact of AC on rates of methylmercury production and degradation, and on overall microbial activity, in 4 different Hg-contaminated salt marsh soils. The study was done over 28 days in anaerobic, sulfate-reducing slurries. A double label of enriched mercury isotopes (Me199Hg and inorganic 201Hg) was used to separately follow de novo Me201Hg production and Me199Hg degradation. AC amendments decreased both methylation and demethylation rate constants relative to un-amended controls, but the impact on demethylation was stronger. The addition of 5% (dry weight) regenerated AC to soil slurries drove demethylation rate constants to nearly zero; i.e. MeHg sorption to AC almost totally blocked its degradation. The net impact was increased solid phase MeHg concentrations in some of the soil slurries with the highest methylation rate constants. However, the net impact of AC amendments was to increase MeHg (and inorganic Hg) partitioning to the soil phase and decrease concentrations in the aqueous phase. AC significantly decreased aqueous phase inorganic Hg and MeHg concentrations after 28 days. Overall, the efficacy of AC in reducing aqueous MeHg was highest in the soils with the highest MeHg concentrations. The AC addition did not significantly impact microbial activity, as

  8. AP endonucleases process 5-methylcytosine excision intermediates during active DNA demethylation in Arabidopsis.

    Science.gov (United States)

    Lee, Jiyoon; Jang, Hosung; Shin, Hosub; Choi, Woo Lee; Mok, Young Geun; Huh, Jin Hoe

    2014-10-01

    DNA methylation is a primary epigenetic modification regulating gene expression and chromatin structure in many eukaryotes. Plants have a unique DNA demethylation system in that 5-methylcytosine (5mC) is directly removed by DNA demethylases, such as DME/ROS1 family proteins, but little is known about the downstream events. During 5mC excision, DME produces 3'-phosphor-α, β-unsaturated aldehyde and 3'-phosphate by successive β- and δ-eliminations, respectively. The kinetic studies revealed that these 3'-blocking lesions persist for a significant amount of time and at least two different enzyme activities are required to immediately process them. We demonstrate that Arabidopsis AP endonucleases APE1L, APE2 and ARP have distinct functions to process such harmful lesions to allow nucleotide extension. DME expression is toxic to E. coli due to excessive 5mC excision, but expression of APE1L or ARP significantly reduces DME-induced cytotoxicity. Finally, we propose a model of base excision repair and DNA demethylation pathway unique to plants. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  9. Clozapine and sulpiride but not haloperidol or olanzapine activate brain DNA demethylation.

    Science.gov (United States)

    Dong, E; Nelson, M; Grayson, D R; Costa, E; Guidotti, A

    2008-09-09

    Cortical GABAergic dysfunction, a hallmark of both schizophrenia (SZ) and bipolar (BP) disorder pathophysiologies may relate to the hypermethylation of GABAergic gene promoters (i.e., reelin and GAD67). Benefits elicited by a combination of atypical antipsychotics with valproate (VPA) (a histone deacetylase inhibitor that may also activate brain DNA demethylation) in SZ or BP disorder treatment prompted us to investigate whether the beneficial action of this association depends on induction of a putative DNA demethylase activity. To monitor this activity, we measured the ratio of 5-methyl cytosine to unmethylated cytosine in reelin and GAD67 promoters in the mouse frontal cortex and striatum. We compared normal mice with mice pretreated with l-methionine (5.2 mmol/kg s.c. twice a day for 7 days) to hypermethylate promoters, including reelin and GAD67. Clinically relevant doses of clozapine (CLZ) (3.8 to 15 micromol/kg twice a day s.c. for 3 days) and sulpiride (SULP) (12.5 to 50 micromol/kg twice a day for 3 days) but not clinically relevant doses of haloperidol (HAL) (1.3 to 4 micromol/kg twice a day s.c. for 3 days) or olanzapine (OLZ) (4 to 15 micromol/kg twice a day for 3 days) exhibited dose-related increases in the cortical and striatal demethylation of hypermethylated reelin and GAD67 promoters. These effects of CLZ and SULP were dramatically potentiated by a clinically relevant VPA dose (0.5 mmol/kg twice a day for 3 days). By activating a DNA demethylase, the association of CLZ or SULP with VPA may facilitate a chromatin remodeling that normalizes the GABAergic gene expression down-regulation detected in the telencephalic regions of SZ and BP patients.

  10. IL-2 and GM-CSF are regulated by DNA demethylation during activation of T cells, B cells and macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yan [College of Animal Science and Technology, Northwest A and F University, Yangling, Shaanxi 712100 (China); Department of Genome Biology, John Curtin School of Medical Research, The Australian National University, ACT 2601 (Australia); Ohms, Stephen J. [ACRF Biomolecular Resource Facility, John Curtin School of Medical Research, The Australian National University, ACT 2601 (Australia); Shannon, Frances M. [Department of Genome Biology, John Curtin School of Medical Research, The Australian National University, ACT 2601 (Australia); The University of Canberra, ACT 2602 (Australia); Sun, Chao, E-mail: sunchao2775@163.com [College of Animal Science and Technology, Northwest A and F University, Yangling, Shaanxi 712100 (China); Fan, Jun Y., E-mail: jun.fan@anu.edu.au [Department of Genome Biology, John Curtin School of Medical Research, The Australian National University, ACT 2601 (Australia)

    2012-03-23

    Highlights: Black-Right-Pointing-Pointer DNA methylation is dynamic and flexible and changes rapidly upon cell activation. Black-Right-Pointing-Pointer DNA methylation controls the inducible gene expression in a given cell type. Black-Right-Pointing-Pointer Some enzymes are involved in maintaining the methylation profile of immune cells. -- Abstract: DNA demethylation has been found to occur at the promoters of a number of actively expressed cytokines and is believed to play a critical role in transcriptional regulation. While many DNA demethylation studies have focused on T cell activation, proliferation and differentiation, changes in DNA methylation in other types of immune cells are less well studied. We found that the expression of two cytokines (IL-2 and GM-CSF) responded differently to activation in three types of immune cells: EL4, A20 and RAW264.7 cells. Using the McrBC and MeDIP approaches, we observed decreases in DNA methylation at a genome-wide level and at the promoters of the genes of these cytokines. The expression of several potential enzymes/co-enzymes involved in the DNA demethylation pathways seemed to be associated with immune cell activation.

  11. Regulation of Active DNA Demethylation by a Methyl-CpG-Binding Domain Protein in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Qi Li

    2015-05-01

    Full Text Available Active DNA demethylation plays crucial roles in the regulation of gene expression in both plants and animals. In Arabidopsis thaliana, active DNA demethylation is initiated by the ROS1 subfamily of 5-methylcytosine-specific DNA glycosylases via a base excision repair mechanism. Recently, IDM1 and IDM2 were shown to be required for the recruitment of ROS1 to some of its target loci. However, the mechanism(s by which IDM1 is targeted to specific genomic loci remains to be determined. Affinity purification of IDM1- and IDM2- associating proteins demonstrated that IDM1 and IDM2 copurify together with two novel components, methyl-CpG-binding domain protein 7 (MBD7 and IDM2-like protein 1 (IDL1. IDL1 encodes an α-crystallin domain protein that shows high sequence similarity with IDM2. MBD7 interacts with IDM2 and IDL1 in vitro and in vivo and they form a protein complex associating with IDM1 in vivo. MBD7 directly binds to the target loci and is required for the H3K18 and H3K23 acetylation in planta. MBD7 dysfunction causes DNA hypermethylation and silencing of reporter genes and a subset of endogenous genes. Our results suggest that a histone acetyltransferase complex functions in active DNA demethylation and in suppression of gene silencing at some loci in Arabidopsis.

  12. AP endonucleases process 5-methylcytosine excision intermediates during active DNA demethylation in Arabidopsis

    OpenAIRE

    Lee, Jiyoon; Jang, Hosung; Shin, Hosub; Choi, Woo Lee; Mok, Young Geun; Huh, Jin Hoe

    2014-01-01

    DNA methylation is a primary epigenetic modification regulating gene expression and chromatin structure in many eukaryotes. Plants have a unique DNA demethylation system in that 5-methylcytosine (5mC) is directly removed by DNA demethylases, such as DME/ROS1 family proteins, but little is known about the downstream events. During 5mC excision, DME produces 3?-phosphor-?, ?-unsaturated aldehyde and 3?-phosphate by successive ?- and ?-eliminations, respectively. The kinetic studies revealed tha...

  13. Coordinated activation of candidate proto-oncogenes and cancer testes antigens via promoter demethylation in head and neck cancer and lung cancer.

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    Ian M Smith

    Full Text Available BACKGROUND: Epigenetic alterations have been implicated in the pathogenesis of solid tumors, however, proto-oncogenes activated by promoter demethylation have been sporadically reported. We used an integrative method to analyze expression in primary head and neck squamous cell carcinoma (HNSCC and pharmacologically demethylated cell lines to identify aberrantly demethylated and expressed candidate proto-oncogenes and cancer testes antigens in HNSCC. METHODOLOGY/PRINCIPAL FINDINGS: We noted coordinated promoter demethylation and simultaneous transcriptional upregulation of proto-oncogene candidates with promoter homology, and phylogenetic footprinting of these promoters demonstrated potential recognition sites for the transcription factor BORIS. Aberrant BORIS expression correlated with upregulation of candidate proto-oncogenes in multiple human malignancies including primary non-small cell lung cancers and HNSCC, induced coordinated proto-oncogene specific promoter demethylation and expression in non-tumorigenic cells, and transformed NIH3T3 cells. CONCLUSIONS/SIGNIFICANCE: Coordinated, epigenetic unmasking of multiple genes with growth promoting activity occurs in aerodigestive cancers, and BORIS is implicated in the coordinated promoter demethylation and reactivation of epigenetically silenced genes in human cancers.

  14. Fluconazole Binding and Sterol Demethylation in Three CYP51 Isoforms Indicate Differences in Active Site Topology

    Energy Technology Data Exchange (ETDEWEB)

    Bellamine, A.; Lepesheva, Galina I.; Waterman, Mike (Vanderbilt)

    2010-11-16

    14{alpha}-Demethylase (CYP51) is a key enzyme in all sterol biosynthetic pathways (animals, fungi, plants, protists, and some bacteria), catalyzing the removal of the C-14 methyl group following cyclization of squalene. Based on mutations found in CYP51 genes from Candida albicans azole-resistant isolates obtained after fluconazole treatment of fungal infections, and using site-directed mutagenesis, we have found that fluconazole binding and substrate metabolism vary among three different CYP51 isoforms: human, fungal, and mycobacterial. In C. albicans, the Y132H mutant from isolates shows no effect on fluconazole binding, whereas the F145L mutant results in a 5-fold increase in its IC{sub 50} for fluconazole, suggesting that F145 (conserved only in fungal 14{alpha}-demethylases) interacts with this azole. In C. albicans, F145L accounts, in part, for the difference in fluconazole sensitivity reported between mammals and fungi, providing a basis for treatment of fungal infections. The C. albicans Y132H and human Y145H CYP51 mutants show essentially no effect on substrate metabolism, but the Mycobacterium tuberculosis F89H CYP51 mutant loses both its substrate binding and metabolism. Because these three residues align in the three isoforms, the results indicate that their active sites contain important structural differences, and further emphasize that fluconazole and substrate binding are uncoupled properties.

  15. Azacytidine and decitabine induce gene-specific and non-random DNA demethylation in human cancer cell lines.

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    Sabine Hagemann

    Full Text Available The DNA methyltransferase inhibitors azacytidine and decitabine represent archetypal drugs for epigenetic cancer therapy. To characterize the demethylating activity of azacytidine and decitabine we treated colon cancer and leukemic cells with both drugs and used array-based DNA methylation analysis of more than 14,000 gene promoters. Additionally, drug-induced demethylation was compared to methylation patterns of isogenic colon cancer cells lacking both DNA methyltransferase 1 (DNMT1 and DNMT3B. We show that drug-induced demethylation patterns are highly specific, non-random and reproducible, indicating targeted remethylation of specific loci after replication. Correspondingly, we found that CG dinucleotides within CG islands became preferentially remethylated, indicating a role for DNA sequence context. We also identified a subset of genes that were never demethylated by drug treatment, either in colon cancer or in leukemic cell lines. These demethylation-resistant genes were enriched for Polycomb Repressive Complex 2 components in embryonic stem cells and for transcription factor binding motifs not present in demethylated genes. Our results provide detailed insights into the DNA methylation patterns induced by azacytidine and decitabine and suggest the involvement of complex regulatory mechanisms in drug-induced DNA demethylation.

  16. Benzydamine N-oxygenation as an index for flavin-containing monooxygenase activity and benzydamine N-demethylation by cytochrome P450 enzymes in liver microsomes from rats, dogs, monkeys, and humans.

    Science.gov (United States)

    Taniguchi-Takizawa, Tomomi; Shimizu, Makiko; Kume, Toshiyuki; Yamazaki, Hiroshi

    2015-02-01

    Benzydamine is an anti-inflammatory drug that undergoes flavin-containing monooxygenase (FMO)-dependent metabolism to benzydamine N-oxide; however, benzydamine N-demethylation is also catalyzed by liver microsomes. In this study, benzydamine N-oxygenation and N-demethylation mediated by liver microsomes from rats, dogs, monkeys, and humans were characterized comprehensively. Values of the maximum velocity/Michaelis constant ratio for benzydamine N-oxygenation by liver microsomes from dogs and rats were higher than those from monkeys and humans, despite roughly similar rates of N-demethylation in the four species. Benzydamine N-oxygenation by liver microsomes was extensively suppressed by preheating liver microsomes at 45 °C for 5 min or at 37 °C for 5-10 min without NADPH, and benzydamine N-demethylation was strongly inhibited by 1-aminbobenztriazole. Liver microsomal benzydamine N-oxygenation was inhibited by dimethyl sulfoxide and methimazole, whereas N-demethylation was inhibited by quinidine. High benzydamine N-oxygenation activities of recombinant human FMO1 and FMO3 and human kidney microsomes were observed at pH 8.4, whereas N-demethylation by cytochrome P450 2D6 was faster at pH 7.4. These results suggest that benzydamine N-oxygenation and N-demethylation are mediated by FMO1/3 and P450s, respectively, and that the contribution of FMO to metabolic eliminations of new drug candidates might be underestimated under certain experimental conditions suitable for P450 enzymes.

  17. A pair of transposon-derived proteins function in a histone acetyltransferase complex for active DNA demethylation

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    Duan, Cheng-Guo; Wang, Xingang; Xie, Shaojun; Pan, Li; Miki, Daisuke; Tang, Kai; Hsu, Chuan-Chih; Lei, Mingguang; Zhong, Yingli; Hou, Yueh-Ju; Wang, Zhijuan; Zhang, Zhengjing; Mangrauthia, Satendra K; Xu, Huawei; Zhang, Heng; Dilkes, Brian; Tao, W Andy; Zhu, Jian-Kang

    2017-01-01

    Transposons are generally kept silent by epigenetic mechanisms including DNA methylation. Here, we identified a pair of Harbinger transposon-derived proteins (HDPs), HDP1 and HDP2, as anti-silencing factors in Arabidopsis. hdp1 and hdp2 mutants displayed an enhanced silencing of transgenes and some transposons. Phylogenetic analyses revealed that HDP1 and HDP2 were co-domesticated from the Harbinger transposon-encoded transposase and DNA-binding protein, respectively. HDP1 interacts with HDP2 in the nucleus, analogous to their transposon counterparts. Moreover, HDP1 and HDP2 are associated with IDM1, IDM2, IDM3 and MBD7 that constitute a histone acetyltransferase complex functioning in DNA demethylation. HDP2 and the methyl-DNA-binding protein MBD7 share a large set of common genomic binding sites, indicating that they jointly determine the target specificity of the histone acetyltransferase complex. Thus, our data revealed that HDP1 and HDP2 constitute a functional module that has been recruited to a histone acetyltransferase complex to prevent DNA hypermethylation and epigenetic silencing. PMID:27934869

  18. TET 蛋白、TDG 介导的 DNA 主动去甲基化的研究进展%Research progress of TET enzyme-and TDG-mediated DNA active demethylation

    Institute of Scientific and Technical Information of China (English)

    石佳; 匡野; 宋杰

    2016-01-01

    DNA methylation exerts a profound effect upon the genome stability,transcription and translation processes.In recent years,breakthrough studies of ten-eleven translocation (TET)enzyme family significantly deepen our understanding of DNA demethylation.5-Hydroxymethylcytosine (5mC),as a key inter-mediate of DNA demethylation,can eventually reduce 5mC to cytosine either through replication-related passive DNA demethylation pathway or DNA active demethylation pathway of base excision repair (BER)mediated by oxidation,reduction and thymine-DNA glycosylase (TDG).Accumulated evidence has demonstrated that DNA active demethylation is of pivotal biological significance.This article summarized the research progress of DNA active demethylation in recent years,especially the research progress of TET and TDG-mediated DNA active demethylation,providing theoretical reference for further investigations.%DNA 甲基化在基因组的稳定性、转录和翻译过程中都有深远的影响。近年来,学者们对 TET (ten-eleven translocation)蛋白家族的研究突破大大提高了人们对 DNA 去甲基化的理解。5-甲基胞嘧啶(5mC)是 DNA 去甲基化过程中的关键中间体,它能通过与复制相关的 DNA 被动去甲基化途径或经过氧化、还原及胸腺嘧啶 DNA 糖苷酶(TDG)介导的碱基切除修复的 DNA 主动去甲基化途径,最终将5mC 还原为胞嘧啶。许多证据表明 DNA 主动去甲基化过程具有重要的生物学意义。该文综述了近年来 DNA 主动去甲基化的研究进展,重点阐述了 TET 蛋白、TDG 介导的 DNA 主动去甲基化途径的新进展,为进一步的深入研究提供理论支持。

  19. Interactions between CYP2C9 and CYP2C19 in reconstituted binary systems influence their catalytic activity: possible rationale for the inability of CYP2C19 to catalyze methoxychlor demethylation in human liver microsomes.

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    Hazai, Eszter; Kupfer, David

    2005-01-01

    Previous studies in our laboratory showed that among cDNA-expressed human cytochrome P450 (P450) supersomes, CYP2C19 was the most active in methoxychlor-O-demethylation. However, based on the lack of inhibition of methoxychlor-O-demethylation by monoclonal anti-CYP2C19 antibodies in human liver microsomes (HLM), CYP2C19 did not seem to catalyze that reaction in HLM. By contrast, CYP2C9, much less active than CYP2C19 in supersomes, was the most active in HLM. The current study examines whether the lack of methoxychlor-O-demethylation by CYP2C19 in HLM was due to CYP2C19 exhibiting inferior competition for the NADPH-cytochrome P450 reductase (CPR) versus CYP2C9 and explores the interactions between CYP2C9 and CYP2C19 in a singular and binary complex of a reconstituted system. When reconstituted with CPR, cytochrome b(5), and lipid, purified CYP2C19 and CYP2C9 catalyzed methoxychlor-O-demethylation. However, whereas equimolar CPR to CYP2C9 supported maximal rates of methoxychlor demethylation and diclofenac hydroxylation, the rate of methoxychlor demethylation by CYP2C19 was not fully saturated, even with a 9-fold molar excess of CPR over CYP2C19. This behavior of CYP2C19 was also observed with S-mephenytoin as the substrate. When a binary reconstitution system was prepared by mixing CYP2C9 and CYP2C19 enzymes, methoxychlor-O-demethylation and S-mephenytoin hydroxylation by CYP2C19 were dramatically inhibited. Inhibition depended on the amount of CPR and substrate used. By contrast, in the incubation containing CYP2C9, diclofenac hydroxylation was activated by the presence of CYP2C19. These results show that interactions among P450 enzymes can modulate their catalytic rates, which depend on the substrate undergoing metabolism.

  20. Demethylation of Quinine Using Anhydrous Aluminium Trichloride

    OpenAIRE

    Aiyi Asnawi; As’ari Nawawi; Rahmana Emran Kartasasmita; Slamet Ibrahim3)

    2011-01-01

    Quinine is a natural alkaloid having a methoxy group bound to quinoline ring and an allyl group bound to quinuclidine ring. Demethylation of quinine applying strong acid such as HBr or HI at high temperature was unsuccessful. The aim of this research was to obtain demethylated quinine by means of mild and selective demethylation procedure to prevent the addition reaction of allyl group. Selective demethylation of quinine has been carried out using anhydrous aluminium trichloride as reagent. T...

  1. Process for demethylating dimethylsulfonium compounds

    NARCIS (Netherlands)

    Hansen, Theo; van der Maarel, Marc

    1998-01-01

    PCT No. PCT/EP94/01640 Sec. 371 Date Nov. 14, 1995 Sec. 102(e) Date Nov. 14, 1995 PCT Filed May 16, 1994 PCT Pub. No. WO94/26918 PCT Pub. Date Nov. 24, 1994Process for preparing S-methylmercapto and mercapto compounds comprising the step of demethylating a dimethylsulfonium compound of formula I to

  2. Non-small-cell lung cancer-induced immunosuppression by increased human regulatory T cells via Foxp3 promoter demethylation.

    Science.gov (United States)

    Ke, Xing; Zhang, Shuping; Xu, Jian; Liu, Genyan; Zhang, Lixia; Xie, Erfu; Gao, Li; Li, Daqian; Sun, Ruihong; Wang, Fang; Pan, Shiyang

    2016-05-01

    Patients with non-small-cell lung cancer (NSCLC) have immune defects that are poorly understood. Forkhead box protein P3 (Foxp3) is crucial for immunosuppression by CD4(+) regulatory T cells (Tregs). It is not well known how NSCLC induces Foxp3 expression and causes immunosuppression in tumor-bearing patients. Our study found a higher percentage of CD4(+) Tregs in the peripheral blood of NSCLC compared with healthy donors. NSCLC patients showed demethylation of eight CpG sites within the Foxp3 promoter with methylation ratios negatively correlated with CD4(+)CD25(+)Foxp3(+) T levels. Foxp3 expression in CD4(+) Tregs was directly regulated by Foxp3 promoter demethylation and was involved in immunosuppression by NSCLC. To verify the effect of tumor cells on the phenotype and function of CD4(+) Tregs, we established a coculture system using NSCLC cell line and healthy CD4(+) T cells and showed that SPC-A1 induced IL-10 and TGF-β1 secretion by affecting the function of CD4(+) Tregs. The activity of DNA methyltransferases from CD4(+) T was decreased during this process. Furthermore, eight CpG sites within the Foxp3 promoter also appeared to have undergone demethylation. Foxp3 is highly expressed in CD4(+) T cells, and this may be caused by gene promoter demethylation. These induced Tregs are highly immunosuppressive and dramatically inhibit the proliferative activity of naïve CD4(+) T cells. Our study provides one possible mechanism describing Foxp3 promoter demethylation changes by which NSCLC down-regulates immune responses and contributes to tumor progression. Foxp3 represents an important target for NSCLC anti-tumor immunotherapy.

  3. Recent activities of the Seismology Division Early Career Representative(s)

    Science.gov (United States)

    Agius, Matthew; Van Noten, Koen; Ermert, Laura; Mai, P. Martin; Krawczyk, CharLotte

    2016-04-01

    The European Geosciences Union is a bottom-up-organisation, in which its members are represented by their respective scientific divisions, committees and council. In recent years, EGU has embarked on a mission to reach out for its numerous 'younger' members by giving awards to outstanding young scientists and the setting up of Early Career Scientists (ECS) representatives. The division representative's role is to engage in discussions that concern students and early career scientists. Several meetings between all the division representatives are held throughout the year to discuss ideas and Union-wide issues. One important impact ECS representatives have had on EGU is the increased number of short courses and workshops run by ECS during the annual General Assembly. Another important contribution of ECS representatives was redefining 'Young Scientist' to 'Early Career Scientist', which avoids discrimination due to age. Since 2014, the Seismology Division has its own ECS representative. In an effort to more effectively reach out for young seismologists, a blog and a social media page dedicated to seismology have been set up online. With this dedicated blog, we'd like to give more depth to the average browsing experience by enabling young researchers to explore various seismology topics in one place while making the field more exciting and accessible to the broader community. These pages are used to promote the latest research especially of young seismologists and to share interesting seismo-news. Over the months the pages proved to be popular, with hundreds of views every week and an increased number of followers. An online survey was conducted to learn more about the activities and needs of early career seismologists. We present the results from this survey, and the work that has been carried out over the last two years, including detail of what has been achieved so far, and what we would like the ECS representation for Seismology to achieve. Young seismologists are

  4. Identification of Three New N-Demethylated and O-Demethyled Bisbenzylisoquinoline Alkaloid Metabolites of Isoliensinine from Dog Hepatic Microsomes

    Directory of Open Access Journals (Sweden)

    Su Zeng

    2012-10-01

    Full Text Available Isoliensinine, a natural phenolic bisbenzyltetrahydroisoquinoline alkaloid, has received considerable attention for its potential biological effects such as antioxidant and anti-HIV activities. From the dog hepatic microsomes of isoliensinine, three new N-demethylated and O-demethylated metabolites, 2-N-desmethyl-isoliensinine (M1, 2'-N-desmethylisoliensinine (M2, and 2'-N-6-O-didesmethylisoliensinine (M3, were identified by high-performance liquid chromatography and data-dependent electrospray ionization tandem mass spectrometry. Possible metabolic pathways for isoliensinine have been proposed. The result should prove very helpful for evaluation of the drug-like properties of isoliensinine and other bisbenzylisoquinoline alkaloids.

  5. Non-Growth-Associated Demethylation of Dimethylsulfoniopropionate by (Homo)acetogenic Bacteria

    Science.gov (United States)

    Jansen, Michael; Hansen, Theo A.

    2001-01-01

    The demethylation of the algal osmolyte dimethylsulfoniopropionate (DMSP) to methylthiopropionate (MTPA) by (homo)acetogenic bacteria was studied. Five Eubacterium limosum strains (including the type strain), Sporomusa ovata DSM 2662T, Sporomusa sphaeroides DSM 2875T, and Acetobacterium woodii DSM 1030T were shown to demethylate DMSP stoichiometrically to MTPA. The (homo)acetogenic fermentation based on this demethylation did not result in any significant increase in biomass. The analogous demethylation of glycine betaine to dimethylglycine does support growth of acetogens. In batch cultures of E. limosum PM31 DMSP and glycine betaine were demethylated simultaneously. In mixed substrates experiments with fructose-DMSP or methanol-DMSP, DMSP was used rapidly but only after exhaustion of the fructose or the methanol. In steady-state fructose-limited chemostat cultures (at a dilution rate of 0.03 h−1) with DMSP as a second reservoir substrate, DMSP was biotransformed to MTPA but this did not result in higher biomass values than in cultures without DMSP; cells from such cultures demethylated DMSP at rates of approximately 50 nmol min−1 mg of protein−1, both after growth in the presence of DMSP and after growth in its absence. In cell extracts of glycine betaine-grown strain PM31, DMSP demethylation activities of 21 to 24 nmol min−1 mg of protein−1 were detected with tetrahydrofolate as a methyl acceptor; the activities seen with glycine betaine were approximately 10-fold lower. A speculative explanation for the demethylation of DMSP without an obvious benefit for the organism is that the DMSP-demethylating activity is catalyzed by the glycine betaine-demethylating enzyme and that a transport-related factor, in particular a higher energy demand for DMSP transport across the cytoplasmic membrane than for glycine betaine transport, may reduce the overall ATP yield of the fermentation to virtually zero. PMID:11133459

  6. A promoter DNA demethylation landscape of human hematopoietic differentiation.

    Science.gov (United States)

    Calvanese, Vincenzo; Fernández, Agustín F; Urdinguio, Rocío G; Suárez-Alvarez, Beatriz; Mangas, Cristina; Pérez-García, Vicente; Bueno, Clara; Montes, Rosa; Ramos-Mejía, Verónica; Martínez-Camblor, Pablo; Ferrero, Cecilia; Assenov, Yassen; Bock, Christoph; Menendez, Pablo; Carrera, Ana Clara; Lopez-Larrea, Carlos; Fraga, Mario F

    2012-01-01

    Global mechanisms defining the gene expression programs specific for hematopoiesis are still not fully understood. Here, we show that promoter DNA demethylation is associated with the activation of hematopoietic-specific genes. Using genome-wide promoter methylation arrays, we identified 694 hematopoietic-specific genes repressed by promoter DNA methylation in human embryonic stem cells and whose loss of methylation in hematopoietic can be associated with gene expression. The association between promoter methylation and gene expression was studied for many hematopoietic-specific genes including CD45, CD34, CD28, CD19, the T cell receptor (TCR), the MHC class II gene HLA-DR, perforin 1 and the phosphoinositide 3-kinase (PI3K) and results indicated that DNA demethylation was not always sufficient for gene activation. Promoter demethylation occurred either early during embryonic development or later on during hematopoietic differentiation. Analysis of the genome-wide promoter methylation status of induced pluripotent stem cells (iPSCs) generated from somatic CD34(+) HSPCs and differentiated derivatives from CD34(+) HSPCs confirmed the role of DNA methylation in regulating the expression of genes of the hemato-immune system, and indicated that promoter methylation of these genes may be associated to stemness. Together, these data suggest that promoter DNA demethylation might play a role in the tissue/cell-specific genome-wide gene regulation within the hematopoietic compartment.

  7. Dynamic and selective HERV RNA expression in neuroblastoma cells subjected to variation in oxygen tension and demethylation.

    Science.gov (United States)

    Hu, Lijuan; Uzhameckis, Dmitrijs; Hedborg, Fredrik; Blomberg, Jonas

    2016-01-01

    We studied HERV expression in cell lines after hypoxia, mitogenic stimulation, and demethylation, to better understand if hypoxia may play a role in ERV activation also within the nervous system, as represented by neuroblastoma cell lines. The level of RNA of four human ERV groups (HERVs) (HERVE, I/T, H, and W), and three housekeeping genes, of different cell lines including A549, COS-1, Namalwa, RD-L and Vero-E6, as well as human neuroblastoma cell lines SH-SY5Y, SK-N-DZ, and SK-N-AS were studied using reverse transcription and real-time quantitative PCR (QPCR). During the course of recovery from hypoxia a pronounced and selective activation of RNA expression of HERVW-like sequences, but not of HERVE, I/T, H, and three housekeeping genes, was found in the neuroblastoma cell lines, most pronounced in SK-N-DZ. In the SK-N-DZ cell line, we also tested the expression of HERVs after chemical treatments. HERVW-like sequences were selectively upregulated by 5-azacytidine, a demethylating agent. Some HERVW loci seem especially responsive to hypoxia and demethylation. HERV expression in neuroblastoma cells is selectively and profoundly influenced by some physiological and chemical stimuli.

  8. Gender Differences in Global but Not Targeted Demethylation in iPSC Reprogramming

    Directory of Open Access Journals (Sweden)

    Inês Milagre

    2017-01-01

    Full Text Available Global DNA demethylation is an integral part of reprogramming processes in vivo and in vitro, but whether it occurs in the derivation of induced pluripotent stem cells (iPSCs is not known. Here, we show that iPSC reprogramming involves both global and targeted demethylation, which are separable mechanistically and by their biological outcomes. Cells at intermediate-late stages of reprogramming undergo transient genome-wide demethylation, which is more pronounced in female cells. Global demethylation requires activation-induced cytidine deaminase (AID-mediated downregulation of UHRF1 protein, and abolishing demethylation leaves thousands of hypermethylated regions in the iPSC genome. Independently of AID and global demethylation, regulatory regions, particularly ESC enhancers and super-enhancers, are specifically targeted for hypomethylation in association with transcription of the pluripotency network. Our results show that global and targeted DNA demethylation are conserved and distinct reprogramming processes, presumably because of their respective roles in epigenetic memory erasure and in the establishment of cell identity.

  9. Simultaneous quantification of phencynonate and its active metabolite N-demethyl phencynonate in human plasma using liquid chromatography and isotope-dilution mass spectrometry.

    Science.gov (United States)

    Chen, Zhengang; Xie, Hui; Liu, Jinbo; Wang, Guangshun

    2015-09-01

    A sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to simultaneously quantify phencynonate (PCN) and its major metabolite N-demethyl phencynonate (DM-PCN) in human plasma. Following one-step liquid-liquid extraction, the analytes were separated on a reversed-phase C18 column. Methanol and 0.02% formic acid in 10 mM ammonium acetate (62:38, v/v) was used as isocratic mobile phase at a flow-rate of 0.3 mL/min. An API 5000 tandem mass spectrometer equipped with a Turbo IonSpray ionization source was used as the detector and was operated in the positive ion mode. Multiple reaction monitoring using the transition of m/z 358.4 → m/z 156.2, m/z 344.4 → m/z 142.2, and m/z 361.3 → m/z 159.2 was performed to quantify PCN, DM-PCN, and the internal standard (D3 -PCN), respectively. This approach showed a lower limit of quantification of 10 pg/mL and 25 pg/mL for PCN and DM-PCN in plasma, respectively. This sensitivity was at least 50-fold superior to previously reported ones and thus enabled the approach well applicable to low-dose pharmacokinetic studies. The intra- and inter-day precisions were less than 14.2 % at each QC level for both PCN and DM-PCN. The inter-day relative errors ranged from -1.9% to -4.9% for PCN, and from 0.6% to 6.4% for DM-PCN. As a proof of principle, the validated method was successfully applied to simultaneous quantification of circulating PCN and DM-PCN in healthy subjects after a single oral administration of 2 mg phencynonate hydrochloride pellet.

  10. Oncogenic Myc Induces Expression of Glutamine Synthetase through Promoter Demethylation.

    Science.gov (United States)

    Bott, Alex J; Peng, I-Chen; Fan, Yongjun; Faubert, Brandon; Zhao, Lu; Li, Jinyu; Neidler, Sarah; Sun, Yu; Jaber, Nadia; Krokowski, Dawid; Lu, Wenyun; Pan, Ji-An; Powers, Scott; Rabinowitz, Joshua; Hatzoglou, Maria; Murphy, Daniel J; Jones, Russell; Wu, Song; Girnun, Geoffrey; Zong, Wei-Xing

    2015-12-01

    c-Myc is known to promote glutamine usage by upregulating glutaminase (GLS), which converts glutamine to glutamate that is catabolized in the TCA cycle. Here we report that in a number of human and murine cells and cancers, Myc induces elevated expression of glutamate-ammonia ligase (GLUL), also termed glutamine synthetase (GS), which catalyzes the de novo synthesis of glutamine from glutamate and ammonia. This is through upregulation of a Myc transcriptional target thymine DNA glycosylase (TDG), which promotes active demethylation of the GS promoter and its increased expression. Elevated expression of GS promotes cell survival under glutamine limitation, while silencing of GS decreases cell proliferation and xenograft tumor growth. Upon GS overexpression, increased glutamine enhances nucleotide synthesis and amino acid transport. These results demonstrate an unexpected role of Myc in inducing glutamine synthesis and suggest a molecular connection between DNA demethylation and glutamine metabolism in Myc-driven cancers.

  11. Engineering activities on the ITER representative diagnostic equatorial port plug

    Energy Technology Data Exchange (ETDEWEB)

    Meunier, L. [Association Euratom CEA, CEA/DSM/IRFM (France)], E-mail: lmeunier@cea.fr; Doceul, L.; Salasca, S.; Martins, J.-P.; Jullien, F.; Dechelle, Christian; Bidaud, Pierre; Pilard, Vincent; Terra, Alexis; Ogea, Mathieu [Association Euratom CEA, CEA/DSM/IRFM (France); Ciattaglia, Emanuela [EFDA CSU, Garching (Germany); Walker, Christopher [ITER International Organisation (France)

    2009-06-15

    Most of ITER diagnostic systems are integrated in port plugs, which are water cooled stainless steel structures inserted into the vacuum vessel ports. The port plug must provide basic functions such as neutron and gamma shielding, supporting the first wall armour (BSM), closing the vacuum vessel ports, while supporting the diagnostic equipments. ITER diagnostic port plug must resist a severe environment like high temperature due to neutron interaction with the structures and high electromechanical loading during disruptions events. CEA has contributed to the design and integration tasks in the frame of the representative equatorial port plug EQ no. 01, in particular on the engineering, structural and thermal finite element analysis. These detailed analyses have highlighted some design issues which were worked out through different solutions. This paper contains a description of the engineering activities performed such as: -The static mechanical calculations of the top plate closure system under disruption load. -The static mechanical calculations of the BSM attachment to the port plug. These two first studies led to design changes proposals which significantly improved the behaviour of the structures but also showed that the safety margin with respect to design limits is quite low. -The design of a Diagnostic Shield Module (DSM) integrated inside the port plug and a proposition of attachment scheme, with respect to disruption loads. The manufacturing of the DSM has been taken into account, as well as diagnostic integration inside the structure and maintenance aspects. -The thermal assessment of the port plug under neutronic load during normal operation, with the optimization of the cooling system. The maximum temperature calculated in normal operation has been reduced from 900 deg. C to less than 400 deg. C in the front plate; and the cooling arrangement at the back of the port plug has been simplified without important temperature increase.

  12. Monkey liver cytochrome P450 2C9 is involved in caffeine 7-N-demethylation to form theophylline.

    Science.gov (United States)

    Utoh, Masahiro; Murayama, Norie; Uno, Yasuhiro; Onose, Yui; Hosaka, Shinya; Fujino, Hideki; Shimizu, Makiko; Iwasaki, Kazuhide; Yamazaki, Hiroshi

    2013-12-01

    Caffeine (1,3,7-trimethylxanthine) is a phenotyping substrate for human cytochrome P450 1A2. 3-N-Demethylation of caffeine is the main human metabolic pathway, whereas monkeys extensively mediate the 7-N-demethylation of caffeine to form pharmacological active theophylline. Roles of monkey P450 enzymes in theophylline formation from caffeine were investigated using individual monkey liver microsomes and 14 recombinantly expressed monkey P450 enzymes, and the results were compared with those for human P450 enzymes. Caffeine 7-N-demethylation activity in microsomes from 20 monkey livers was not strongly inhibited by α-naphthoflavone, quinidine or ketoconazole, and was roughly correlated with diclofenac 4'-hydroxylation activities. Monkey P450 2C9 had the highest activity for caffeine 7-N-demethylation. Kinetic analysis revealed that monkey P450 2C9 had a high Vmax/Km value for caffeine 7-N-demethylation, comparable to low Km value for monkey liver microsomes. Caffeine could dock favorably with monkey P450 2C9 modeled for 7-N-demethylation and with human P450 1A2 for 3-N-demethylation. The primary metabolite theophylline was oxidized to 8-hydroxytheophylline in similar ways by liver microsomes and by recombinant P450s in both humans and monkeys. These results collectively suggest a high activity for monkey liver P450 2C9 toward caffeine 7-N-demethylation, whereas, in humans, P450 1A2-mediated caffeine 3-N-demethylation is dominant.

  13. Structure and function of dioxygenases in histone demethylation and DNA/RNA demethylation

    National Research Council Canada - National Science Library

    Dong, Cheng; Zhang, Heng; Xu, Chao; Arrowsmith, Cheryl H; Min, Jinrong

    2014-01-01

    Iron(II) and 2-oxoglutarate (2OG)-dependent dioxygenases involved in histone and DNA/RNA demethylation convert the cosubstrate 2OG and oxygen to succinate and carbon dioxide, resulting in hydroxylation of the methyl group...

  14. Tetrahydrofolate serves as a methyl acceptor in the demethylation of dimethylsulfoniopropionate in cell extracts of sulfate-reducing bacteria

    NARCIS (Netherlands)

    Jansen, M; Hansen, T.A.

    1998-01-01

    Tetrahydrofolate was shown to function as a methyl acceptor in the anaerobic demethylation of dimethylsulfoniopropionate to methylthiopropionate in cell extracts of the sulfate-reducing bacterium strain WN. Dimethylsulfoniopropionate-dependent activities were 0.56 mu mol methyltetrahydrofolate min(-

  15. Tetrahydrofolate serves as a methyl acceptor in the demethylation of dimethylsulfoniopropionate in cell extracts of sulfate-reducing bacteria

    NARCIS (Netherlands)

    Jansen, M; Hansen, T.A.

    1998-01-01

    Tetrahydrofolate was shown to function as a methyl acceptor in the anaerobic demethylation of dimethylsulfoniopropionate to methylthiopropionate in cell extracts of the sulfate-reducing bacterium strain WN. Dimethylsulfoniopropionate-dependent activities were 0.56 mu mol methyltetrahydrofolate min(-

  16. Ligand binding affinities of arctigenin and its demethylated metabolites to estrogen receptor alpha.

    Science.gov (United States)

    Jin, Jong-Sik; Lee, Jong-Hyun; Hattori, Masao

    2013-01-16

    Phytoestrogens are defined as plant-derived compounds with estrogen-like activities according to their chemical structures and activities. Plant lignans are generally categorized as phytoestrogens. It was reported that (-)-arctigenin, the aglycone of arctiin, was demethylated to (-)-dihydroxyenterolactone (DHENL) by Eubacterium (E.) sp. ARC-2. Through stepwise demethylation, E. sp. ARC-2 produced six intermediates, three mono-desmethylarctigenins and three di-desmethylarctigenins. In the present study, ligand binding affinities of (-)-arctigenin and its seven metabolites, including DHENL, were investigated for an estrogen receptor alpha, and found that demethylated metabolites had stronger binding affinities than (-)-arctigenin using a ligand binding screen assay method. The IC(50) value of (2R,3R)-2-(4-hydroxy-3-methoxybenzyl)-3-(3,4-dihydroxybenzyl)-butyrolactone was 7.9 × 10⁻⁴ M.

  17. Ligand Binding Affinities of Arctigenin and Its Demethylated Metabolites to Estrogen Receptor Alpha

    Directory of Open Access Journals (Sweden)

    Masao Hattori

    2013-01-01

    Full Text Available Phytoestrogens are defined as plant-derived compounds with estrogen-like activities according to their chemical structures and activities. Plant lignans are generally categorized as phytoestrogens. It was reported that (−-arctigenin, the aglycone of arctiin, was demethylated to (−-dihydroxyenterolactone (DHENL by Eubacterium (E. sp. ARC-2. Through stepwise demethylation, E. sp. ARC-2 produced six intermediates, three mono-desmethylarctigenins and three di-desmethylarctigenins. In the present study, ligand binding affinities of (−-arctigenin and its seven metabolites, including DHENL, were investigated for an estrogen receptor alpha, and found that demethylated metabolites had stronger binding affinities than (−-arctigenin using a ligand binding screen assay method. The IC50 value of (2R,3R-2-(4-hydroxy-3-methoxybenzyl-3-(3,4-dihydroxybenzyl-butyrolactone was 7.9 × 10−4 M.

  18. Demethylating Agents in the Treatment of Cancer

    Directory of Open Access Journals (Sweden)

    Paul M. Howell, Jr.

    2010-07-01

    Full Text Available Gene silencing resulting from aberrant DNA methylation can lead to tumorigenesis. Therefore, drugs that inhibit or interfere with DNA methylation have been used to reactivate and induce silenced gene re-expression in malignancies. Two demethylating agents, azacitidine and decitabine, are approved for the treatment of myelodysplastic syndromes (MDS by the U.S. Food and Drug Administration (FDA, and are now considered the standard of care in MDS. In this review, we discuss clinical data, including clinical benefits and toxicities, which led to the approval of azacitidine and decitabine. We also summarize findings from clinical trials that used these two demethylating agents in the treatment of solid tumors. Lastly, we discuss some limitations in the use of azacitidine and decitabine in cancer therapy.

  19. Mining and representing recommendations in actively evolving recommender systems

    DEFF Research Database (Denmark)

    Assent, Ira

    2010-01-01

    ) recommender connections. In this work, we propose mining such active systems to generate easily understandable representations of the recommender network. Users may review these representations to provide active feedback. This approach further enhances the quality of recommendations, especially as topics......Recommender systems provide an automatic means of filtering out interesting items, usually based on past similarity of user ratings. In previous work, we have suggested a model that allows users to actively build a recommender network. Users express trust, obtain transparency, and grow (anonymous...... of interest change over time. Most notably, it extends the amount of control users have over the model that the recommender network builds of their interests....

  20. RNA-directed DNA methylation and demethylation in plants

    Institute of Scientific and Technical Information of China (English)

    CHINNUSAMY; Viswanathan

    2009-01-01

    RNA-directed DNA methylation (RdDM) is a nuclear process in which small interfering RNAs (siRNAs) direct the cytosine methylation of DNA sequences that are complementary to the siRNAs. In plants, double stranded-RNAs (dsRNAs) generated by RNA-dependent RNA polymerase 2 (RDR2) serve as precursors for Dicer-like 3 dependent biogenesis of 24-nt siRNAs. Plant specific RNA polymerase IV (Pol IV) is presumed to generate the initial RNA transcripts that are substrates for RDR2. siRNAs are loaded onto an argonaute4-containing RISC (RNA-induced silencing complex) that targets the de novo DNA methyltransferase DRM2 to RdDM target loci. Nascent RNA transcripts from the target loci are generated by another plant-specific RNA polymerase, Pol V, and these transcripts help recruit com- plementary siRNAs and the associated RdDM effector complex to the target loci in a transcrip- tion-coupled DNA methylation process. Small RNA binding proteins such as ROS3 may direct tar- get-specific DNA demethylation by the ROS1 family of DNA demethylases. Chromatin remodeling en- zymes and histone modifying enzymes also participate in DNA methylation and possibly demethylation. One of the well studied functions of RdDM is transposon silencing and genome stability. In addition, RdDM is important for paramutation, imprinting, gene regulation, and plant development. Lo- cus-specific DNA methylation and demethylation, and transposon activation under abiotic stresses suggest that RdDM is also important in stress responses of plants. Further studies will help illuminate the functions of RdDM in the dynamic control of epigenomes during development and environmental stress responses.

  1. Papaya seed represents a rich source of biologically active isothiocyanate.

    Science.gov (United States)

    Nakamura, Yoshimasa; Yoshimoto, Motoko; Murata, Yoshiyuki; Shimoishi, Yasuaki; Asai, Yumi; Park, Eun Young; Sato, Kenji; Nakamura, Yasushi

    2007-05-30

    In the present study, papaya (Carica papaya) seed and edible pulp were carefully separated and then the contents of benzyl isothiocyanate and the corresponding glucosinolate (benzyl glucosinolate, glucotropaeolin) quantified in each part. The papaya seed with myrosinase inactivation contained >1 mmol of benzyl glucosinolate in 100 g of fresh seed. This content is equivalent to that of Karami daikon (the hottest Japanese white radish) or that of cress. The papaya seed extract also showed a very high activity of myrosinase and, without myrosinase inactivation, produced 460 micromol of benzyl isothiocyanate in 100 g of seed. In contrast, papaya pulp contained an undetectable amount of benzyl glucosinolate and showed no significant myrosinase activity. The n-hexane extract of the papaya seed homogenate was highly effective in inhibiting superoxide generation and apoptosis induction in HL-60 cells, the activities of which are comparable to those of authentic benzyl isothiocyanate.

  2. Structure and function of dioxygenases in histone demethylation and DNA/RNA demethylation

    Directory of Open Access Journals (Sweden)

    Cheng Dong

    2014-11-01

    Full Text Available Iron(II and 2-oxoglutarate (2OG-dependent dioxygenases involved in histone and DNA/RNA demethylation convert the cosubstrate 2OG and oxygen to succinate and carbon dioxide, resulting in hydroxylation of the methyl group of the substrates and subsequent demethylation. Recent evidence has shown that these 2OG dioxygenases play vital roles in a variety of biological processes, including transcriptional regulation and gene expression. In this review, the structure and function of these dioxygenases in histone and nucleic acid demethylation will be discussed. Given the important roles of these 2OG dioxygenases, detailed analysis and comparison of the 2OG dioxygenases will guide the design of target-specific small-molecule chemical probes and inhibitors.

  3. [Effects of phospholipids on oxidative demethylation of dimethylcyclohexylamine by cumene hydroperoxide involving methemoglobin].

    Science.gov (United States)

    Kiseleva, S N; Khatyleva, S Iu; Kisel', M A; Kiselev, P A; Akhrem, A A

    1981-12-01

    The reaction of oxidative demethylation of N-dimethylcyclohexylamine by cumene hydroperoxide involving methemoglobin was studied. Data from differential spectroscopy and kinetic analysis revealed the formation of a methemoglobin--N-dimethylcyclohexylamine--cumene hydroperoxide complex. The inhibiting analysis revealed the radical stages in the process of demethylation. An addition to the reaction mixture of phosphatidyl serine, phosphatidyl inositol and lysophosphatidyl choline at a ratio of 50 divided by 500 molecules per 1 molecule of protein increased the rate of the reaction product accumulation 2--3-fold. Phosphatidyl choline and the ionic detergent sodium cholate did not practically affect the reaction rate under the given experimental conditions. The nature of the activating effect of some phospholipids on oxidative demethylation is discussed.

  4. Epigenetic targets and drug discovery Part 2: Histone demethylation and DNA methylation.

    Science.gov (United States)

    Liu, Ke; Liu, Yanli; Lau, Johnathan L; Min, Jinrong

    2015-07-01

    Chromatin structure is dynamically modulated by various chromatin modifications, such as histone/DNA methylation and demethylation. We have reviewed histone methyltransferases and methyllysine binders in terms of small molecule screening and drug discovery in the first part of this review series. In this part, we will summarize recent progress in chemical probe and drug discovery of histone demethylases and DNA methyltransferases. Histone demethylation and DNA methylation have attracted a lot of attention regarding their biology and disease implications. Correspondingly, many small molecule compounds have been designed to modulate the activity of histone demethylases and DNA methyltransferases, and some of them have been developed into therapeutic drugs or put into clinical trials.

  5. Targeting protein lysine methylation and demethylation in cancers

    Institute of Scientific and Technical Information of China (English)

    Yunlong He; Ilia Korboukh; Jian Jin; Jing Huang

    2012-01-01

    During the last decade,we saw an explosion of studies investigating the role of lysine methylation/demethylation of histones and non-histone proteins,such as p53,NF-kappaB,and E2F1.These ‘Ying-Yang' post-translational modifications are important to fine-tuning the activity of these proteins. Lysine methylation and demethylation are catalyzed by protein lysine methyltransferases (PKMTs) and protein lysine demethylases (PKDMs).PKMTs,PKDMs,and their substrates have been shown to play important roles in cancers.Although the underlying mechanisms of tumorigenesis are still largely unknown,growing evidence is starting to link aberrant regulation of methylation to tumorigenesis.This review focuses on summarizing the recent progress in understanding of the function of protein lysine methylation,and in the discovery of small molecule inhibitors for PKMTs and PKDMs.We also discuss the potential and the caveats of targeting protein lysine methylation for the treatment of cancer.

  6. Demethylation of methylarsonic acid by a microbial community.

    Science.gov (United States)

    Yoshinaga, Masafumi; Cai, Yong; Rosen, Barry P

    2011-05-01

    Arsenic is one of the most widespread environmental carcinogens and has created devastating human health problems worldwide, yet little is known about mechanisms of biotransformation in contaminated regions. Methylarsonic acid [MAs(V)], extensively utilized as an herbicide, is largely demethylated to more toxic inorganic arsenite, which causes environmental problems. To understand the process of demethylation of methylarsenicals, soil samples commonly used on Florida golf courses were studied. Several soil extracts were found to demethylate MAs(V) to inorganic arsenite [As(III)]. From these extracts, a bacterial isolate was capable of reducing MAs(V) to MAs(III) but not of demethylating to As(III). A second bacterial isolate was capable of demethylating MAs(III) to As(III) but not of reducing MAs(V). A mixed culture could carry out the complete process of reduction and demethylation, demonstrating that demethylation of MAs(V) to As(III) is a two-step process. Analysis of the 16S ribosomal DNA sequences of the two organisms identified the MAs(V)-reducing and the MAs(III)-demethylating isolates as belong to Burkholderia and Streptomyces species respectively. This is the first report of a novel pathway of degradation of a methylarsenical herbicide by sequential reduction and demethylation in a microbial soil community, which we propose plays a significant role in the arsenic biogeocycle.

  7. Global DNA hypermethylation-associated cancer chemotherapy resistance and its reversion with the demethylating agent hydralazine

    Directory of Open Access Journals (Sweden)

    Benitez-Bribiesca Luis

    2006-08-01

    Full Text Available Abstract Background The development of resistance to cytotoxic chemotherapy continues to be a major obstacle for successful anticancer therapy. It has been shown that cells exposed to toxic concentrations of commonly used cancer chemotherapy agents develop DNA hypermetylation. Hence, demethylating agents could play a role in overcoming drug resistance. Methods MCF-7 cells were rendered adriamycin-resistant by weekly treatment with adriamycin. Wild-type and the resulting MCF-7/Adr cells were analyzed for global DNA methylation. DNA methyltransferase activity and DNA methyltransferase (dnmt gene expression were also determined. MCF-7/Adr cells were then subjected to antisense targeting of dnmt1, -3a, and -b genes and to treatment with the DNA methylation inhibitor hydralazine to investigate whether DNA demethylation restores sensitivity to adriamycin. Results MCF-7/Adr cells exhibited the multi-drug resistant phenotype as demonstrated by adriamycin resistance, mdr1 gene over-expression, decreased intracellular accumulation of adriamycin, and cross-resistance to paclitaxel. The mdr phenotype was accompanied by global DNA hypermetylation, over-expression of dnmt genes, and increased DNA methyltransferase activity as compared with wild-type MCF-7 cells. DNA demethylation through antisense targeting of dnmts or hydralazine restored adriamycin sensitivity of MCF-7/Adr cells to a greater extent than verapamil, a known inhibitor of mdr protein, suggesting that DNA demethylation interferes with the epigenetic reprogramming that participates in the drug-resistant phenotype. Conclusion We provide evidence that DNA hypermethylation is at least partly responsible for development of the multidrug-resistant phenotype in the MCF-7/Adr model and that hydralazine, a known DNA demethylating agent, can revert the resistant phenotype.

  8. RNA-directed DNA methylation and demethylation in plants

    Institute of Scientific and Technical Information of China (English)

    CHINNUSAMY Viswanathan; ZHU Jian-Kang

    2009-01-01

    A-dlrected DNA methylation (RdDM) Is a nuclear process in which small Interfering RNAs (siRNAs)direct the cytosine methylation of DNA sequences that are complementary to the siRNAs. In plants,double stranded-RNAs (dsRNAs) generated by RNA-dependent RNA polymerase 2 (RDR2) serve as precursors for Dicer-like 3 dependent biogenesis of 24-nt siRNAs. Plant specific RNA polymerase IV (Pol IV) is presumed to generate the initial RNA transcripts that are substrates for RDR2. siRNAs are loaded onto an argonaute4-containlng RlSC (RNA-induced silencing complex) that targets the de novo DNA methyltransferase DRM2 to RdDM target locl. Nascent RNA transcripts from the target loci are generated by another plant-specific RNA polymerase, Pol V, and these transcripts help recruit com-plementary siRNAs and the associated RdDM effector complex to the target loci in a transcrip-tion-coupled DNA methylation process. Small RNA binding proteins such as ROS3 may direct tar-get-specific DNA demethyiation by the ROS1 family of DNA demethylases. Chromatin remodeling en-zymes and histone modifying enzymes also participate in DNA methylation and possibly demethylation.One of the well studied functions of RdOM is transposon silencing and genome stability. In addition,RdDM is important for paramutation, imprinting, gene regulation, and plant development. Locus-specific DNA methylation and demethylation, and transposon activation under abiotic stresses suggest that RdDM is also important in stress responses of plants. Further studies will help illuminate the functions of RdDM in the dynamic control of epigenomes during development and environmental stress responses.

  9. Theoretical study on the N-demethylation mechanism of theobromine catalyzed by P450 isoenzyme 1A2.

    Science.gov (United States)

    Tao, Jing; Kang, Yuan; Xue, Zhiyu; Wang, Yongting; Zhang, Yan; Chen, Qiu; Chen, Zeqin; Xue, Ying

    2015-09-01

    Theobromine, a widely consumed pharmacological active substance, can cause undesirable muscle stiffness, nausea and anorexia in high doses ingestion. The main N-demethylation metabolic mechanism of theobromine catalyzed by P450 isoenzyme 1A2 (CYP1A2) has been explored in this work using the unrestricted hybrid density functional method UB3LYP in conjunction with the LACVP(Fe)/6-31G (H, C, N, O, S, Cl) basis set. Single-point calculations including empirical dispersion corrections were carried out at the higher 6-311++G** basis set. Two N-demethylation pathways were characterized, i.e., 3-N and 7-N demethylations, which involve the initial N-methyl hydroxylation to form carbinolamines and the subsequent carbinolamines decomposition to yield monomethylxanthines and formaldehydes. Our results have shown that the rate-limiting N-methyl hydroxylation occurs via a hydrogen atom transfer (HAT) mechanism, which proceeds in a spin-selective mechanism (SSM) in the gas phase. The carbinolamines generated are prone to decomposition via the contiguous heteroatom-assisted proton-transfer. Strikingly, 3-N demethylation is more favorable than 7-N demethylation due to its lower free energy barrier and 7-methylxanthine therefore is the optimum product reported for the demethylation of theobromine catalyzed by CYP1A2, which are in good agreement with the experimental observation. This work has first revealed the detail N-demethylation mechanisms of theobromine at the theoretical level. It can offer more significant information for the metabolism of purine alkaloid.

  10. Induction of the mesenchymal to epithelial transition by demethylation- activated microRNA-200c is involved in the anti-migration/invasion effects of arsenic trioxide on human breast cancer cells.

    Science.gov (United States)

    Si, Lu; Jiang, Fei; Li, Yuan; Ye, Xianqing; Mu, Juan; Wang, Xingxing; Ning, Shilong; Hu, Chunyan; Li, Zhong

    2015-09-01

    Breast cancer is a major health problem worldwide. Current standard practices for treatment of breast cancer are less than satisfactory because of high rates of metastasis. Arsenic trioxide (As(2)O(3)), which induces demethylation of DNA and causes apoptosis, has been used as an anti-tumor agent. Little is known, however, regarding its anti-metastatic effects. The microRNA-200c (miR-200c), which is frequently lowly expressed in triple negative breast cancers (TNBCs), inhibits metastasis by inducing the mesenchymal to epithelial transition (MET). Here, we report that As(2)O(3) attenuates the migratory and invasive capacities of breast cancer cells, MDA-MB-231 and BT-549. Notably, As(2)O(3) induces an MET in vitro and in vivo, as determined by the increased expression of the epithelial marker, E-cadherin and decreased expressions of mesenchymal markers, N-cadherin and vimentin. Moreover, As(2)O(3) up-regulates the expression of miR-200c through demethylation. Over-expression of miR-200c enhances the expression of E-cadherin and decreases the expressions of N-cadherin and vimentin. Further, in MDA-MB-231 cells exposed to As(2)O(3), knockdown of miR-200c blocks the As(2)O(3) -induced MET. Finally, in MDA-MB-231 and BT-549 cells exposed to As(2)O(3), knockdown of miR-200c decreases the As(2)O(3) -induced inhibition of the migratory and invasive capacities. By identifying a mechanism whereby As(2)O(3) regulates miR-200c and MET, the results establish the anti-migration/invasion potential of arsenic trioxide.

  11. Promoter demethylation of Keap1 gene in human diabetic cataractous lenses

    Energy Technology Data Exchange (ETDEWEB)

    Palsamy, Periyasamy [Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE (United States); Ayaki, Masahiko [Shizuoka National Hospital, Saitama (Japan); Elanchezhian, Rajan [Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE (United States); Shinohara, Toshimichi, E-mail: tshinohara@unmc.edu [Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE (United States)

    2012-07-06

    Highlights: Black-Right-Pointing-Pointer We found significant Keap1 promoter demethylation in diabetic cataractous lenses. Black-Right-Pointing-Pointer Demethylation of Keap1 gene upregulated the expression of Keap1 mRNA and protein. Black-Right-Pointing-Pointer Elevated levels of Keap1 are known to decrease the levels of Nrf2. Black-Right-Pointing-Pointer Thereby, the levels of antioxidant enzymes are suppressed by decreased Nrf2 level. -- Abstract: Age-related cataracts (ARCs) are the major cause of visual impairments worldwide, and diabetic adults tend to have an earlier onset of ARCs. Although age is the strongest risk factor for cataracts, little is known how age plays a role in the development of ARCs. It is known that oxidative stress in the lens increases with age and more so in the lenses of diabetics. One of the central adaptive responses against the oxidative stresses is the activation of the nuclear transcriptional factor, NF-E2-related factor 2 (Nrf2), which then activates more than 20 different antioxidative enzymes. Kelch-like ECH associated protein 1 (Keap1) targets and binds to Nrf2 for proteosomal degradation. We hypothesized that hyperglycemia will lead to a dysfunction of the Nrf2-dependent antioxidative protection in the lens of diabetics. We studied the methylation status of the CpG islands in 15 clear and 21 diabetic cataractous lenses. Our results showed significant levels of demethylated DNA in the Keap1 promoter in the cataractous lenses from diabetic patients. In contrast, highly methylated DNA was found in the clear lens and tumorized human lens epithelial cell (HLEC) lines (SRA01/04). HLECs treated with a demethylation agent, 5-aza-2 Prime deoxycytidine (5-Aza), had a 10-fold higher levels of Keap1 mRNA, 3-fold increased levels of Keap1 protein, produced higher levels of ROS, and increased cell death. Our results indicated that demethylation of the CpG islands in the Keap1 promoter will activate the expression of Keap1 protein, which

  12. The site specific demethylation in the 5'-regulatory area of NMDA receptor 2B subunit gene associated with CIE-induced up-regulation of transcription.

    Directory of Open Access Journals (Sweden)

    Mei Qiang

    Full Text Available BACKGROUND: The NMDA receptor represents a particularly important site of ethanol action in the CNS. We recently reported that NMDA receptor 2B (NR2B gene expression was persistently up-regulated following chronic intermittent ethanol (CIE treatment. Increasing evidence that epigenetic mechanisms are involved in dynamic and long-lasting regulation of gene expression in multiple neuroadaptive processes prompted us to investigate the role of DNA methylation in mediating CIE-induced up-regulation of NR2B gene transcription. To dissect the changes of DNA methylation in the NR2B gene, we have screened a large number of CpG sites within its 5'-regulatory area following CIE treatment. METHODS: Primary cortical cultured neurons were subjected to ethanol treatment in a CIE paradigm. Bisulfite conversion followed by pyrosequencing was used for quantitative measurement and analysis of CpG methylation status within the 5'-regulatory area of the NR2B gene; chromatin immunoprecipitation (ChIP assay was used to examine DNA levels associated with methylation and transcription factor binding. Electrophoretic mobility shift assay (EMSA and in vitro DNA methylation assays were performed to determine the direct impact of DNA methylation on the interaction between DNA and transcription factor and promoter activity. RESULTS: Analysis of individual CpG methylation sites within the NR2B 5'regulatory area revealed three regions with clusters of site-specific CpG demethylation following CIE treatment and withdrawal. This was confirmed by ChIP showing similar decreases of methylated DNA in the same regions. The CIE-induced demethylation is characterized by being located near certain transcription factor binding sequences, AP-1 and CRE, and occurred during treatment as well as after ethanol withdrawal. Furthermore, the increase in vitro of methylated DNA decreased transcription factor binding activity and promoter activity. An additional ChIP assay indicated that the CIE

  13. Simulated vibrational spectra of aflatoxins and their demethylated products and the estimation of the energies of the demethylation reactions

    Science.gov (United States)

    Billes, Ferenc; Móricz, Ágnes M.; Tyihák, Ernő; Mikosch, Hans

    2006-06-01

    The structure of four natural mycotoxins, the aflatoxin B 1, B 2, G 1 and G 2 and their demethylated products were optimized with quantum chemical method. The energies and the thermodynamic functions of the molecules were calculated and applied to calculation of the reaction energies of the demethylations. Further results of the calculations are the vibrational force constants, the infrared spectra of the molecules and the assignments of the spectral bands.

  14. Simultaneous determination of the novel tyrosine kinase inhibitor meditinib and its active metabolite demethylation meditinib in monkey plasma by liquid chromatography-tandem mass spectrometry and its application to pharmacokinetic studies.

    Science.gov (United States)

    Liang, Feng; Kong, Qi; Guo, Yongqi; Wang, Yu; Sun, Dejie; Liu, Shi; Cai, Jinling; Guan, Yongbiao; Ding, Rigao

    2015-08-01

    Meditinib (ME) is a novel tyrosine kinase inhibitor used as an antichronic myeloid leukemia drug. A simple, sensitive and specific LC/MS/MS method was developed and validated for the analysis of ME and its metabolite demethylation meditinib (PI) in monkey plasma using naltrexone as the internal standard. Sample preparation involved protein precipitation with methanol. The analysis was carried out on an Agilent C8 column (3.5 µm, 2.1 × 50 mm). Elution was achieved with a mobile phase gradient varying the proportion of a water solution containing 0.1% formic acid (solvent A) and a 0.1% formic acid in methanol solution (solvent B) at a flow rate of 300 μL/min. The method had a linear calibration curve over the concentration range of 2-1000 ng/mL for ME and 2-1000 ng/mL for PI. The lower limits of quantification of ME and PI were 2 and 2 ng/mL, respectively. The intra- and inter-day precision values were 85%. The assay has been successfully used for pharmacokinetic evaluation of ME and PI using the monkey as an animal model, and those data are reported for the first time.

  15. Participation of the Neighborhood Representatives (Mukhtars into Managerial Activities in Local Level: Burdur Case

    Directory of Open Access Journals (Sweden)

    Mustafa LAMBA

    2017-05-01

    Full Text Available Neighborhood representatives (mukhtars are the nearest administrative units to citizens in local level. It is required to take advantage of that the neighborhood representatives know their districts and residents better than central and local government authorities. In addition, it will be appropriate to the principles of subsidiarity and the European Charter of Local Self Government to determine problems and demands of neighborhoods by their representatives. It is necessary to maintain communication channels and keep close relations with neighborhood representatives by local governments to use that advantage efficiently. It is aimed in this study to determine the participation level of neighborhood representatives into managerial activities in local level. For that purpose, the neighborhood representatives in the center of Burdur province are included in the research. According to the findings, it has been determined that the neighborhood representatives have participated into various activities without experiencing any difficulty, and they have been informed about the services regarding to their neighborhoods, and they have kept close relationship with central and local administrations, and most of them could communicate with local authorities directly. Therefore, it has been concluded that the neighborhood representatives have been influential enough in decision-making mechanisms in local level in Burdur.

  16. Genistein promotes DNA demethylation of the steroidogenic factor 1 (SF-1) promoter in endometrial stromal cells

    Energy Technology Data Exchange (ETDEWEB)

    Matsukura, Hiroshi, E-mail: hmatsukura.epi@mri.tmd.ac.jp [Department of Molecular Epidemiology, Medical Research Institute, Tokyo Medical and Dental University, 2-3-10 Kanda-surugadai, Chiyoda-ku, Tokyo 101-0062 (Japan); Aisaki, Ken-ichi; Igarashi, Katsuhide; Matsushima, Yuko; Kanno, Jun [Division of Cellular and Molecular Toxicology, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501 (Japan); Muramatsu, Masaaki [Department of Molecular Epidemiology, Medical Research Institute, Tokyo Medical and Dental University, 2-3-10 Kanda-surugadai, Chiyoda-ku, Tokyo 101-0062 (Japan); Sudo, Katsuko [Department of Molecular Epidemiology, Medical Research Institute, Tokyo Medical and Dental University, 2-3-10 Kanda-surugadai, Chiyoda-ku, Tokyo 101-0062 (Japan); Animal Research Center, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, Tokyo 160-8402 (Japan); Sato, Noriko, E-mail: nsato.epi@tmd.ac.jp [Department of Molecular Epidemiology, Medical Research Institute, Tokyo Medical and Dental University, 2-3-10 Kanda-surugadai, Chiyoda-ku, Tokyo 101-0062 (Japan)

    2011-08-26

    Highlights: {yields} Genistein (GEN) is a phytoestrogen found in soy products. {yields} GEN demethylated/unsilenced the steroidogenic factor 1 gene in endometrial tissue. {yields} GEN thus altered mRNA expression in uteri of ovariectomized (OVX) mice. {yields} A high-resolution melting assay was used to screen for epigenetic change. {yields} We isolated an endometrial cell clone that was epigenetically modulated by GEN. -- Abstract: It has recently been demonstrated that genistein (GEN), a phytoestrogen in soy products, is an epigenetic modulator in various types of cells; but its effect on endometrium has not yet been determined. We investigated the effects of GEN on mouse uterine cells, in vivo and in vitro. Oral administration of GEN for 1 week induced mild proliferation of the endometrium in ovariectomized (OVX) mice, which was accompanied by the induction of steroidogenic factor 1 (SF-1) gene expression. GEN administration induced demethylation of multiple CpG sites in the SF-1 promoter; these sites are extensively methylated and thus silenced in normal endometrium. The GEN-mediated promoter demethylation occurred predominantly on the luminal side, as opposed to myometrium side, indicating that the epigenetic change was mainly shown in regenerated cells. Primary cultures of endometrial stromal cell colonies were screened for GEN-mediated alterations of DNA methylation by a high-resolution melting (HRM) method. One out of 20 colony-forming cell clones showed GEN-induced demethylation of SF-1. This clone exhibited a high proliferation capacity with continuous colony formation activity through multiple serial clonings. We propose that only a portion of endometrial cells are capable of receiving epigenetic modulation by GEN.

  17. Pluripotency Transcription Factor Oct4 Mediates Stepwise Nucleosome Demethylation and Depletion

    Science.gov (United States)

    Shakya, Arvind; Callister, Catherine; Goren, Alon; Yosef, Nir; Garg, Neha; Khoddami, Vahid; Nix, David; Regev, Aviv

    2015-01-01

    The mechanisms whereby the crucial pluripotency transcription factor Oct4 regulates target gene expression are incompletely understood. Using an assay system based on partially differentiated embryonic stem cells, we show that Oct4 opposes the accumulation of local H3K9me2 and subsequent Dnmt3a-mediated DNA methylation. Upon binding DNA, Oct4 recruits the histone lysine demethylase Jmjd1c. Chromatin immunoprecipitation (ChIP) time course experiments identify a stepwise Oct4 mechanism involving Jmjd1c recruitment and H3K9me2 demethylation, transient FACT (facilitates chromatin transactions) complex recruitment, and nucleosome depletion. Genome-wide and targeted ChIP confirms binding of newly synthesized Oct4, together with Jmjd1c and FACT, to the Pou5f1 enhancer and a small number of other Oct4 targets, including the Nanog promoter. Histone demethylation is required for both FACT recruitment and H3 depletion. Jmjd1c is required to induce endogenous Oct4 expression and fully reprogram fibroblasts to pluripotency, indicating that the assay system identifies functional Oct4 cofactors. These findings indicate that Oct4 sequentially recruits activities that catalyze histone demethylation and depletion. PMID:25582194

  18. Biochemistry and occurrence of O-demethylation in plant metabolism

    Directory of Open Access Journals (Sweden)

    Jillian Hagel

    2010-07-01

    Full Text Available Demethylases play a pivitol role in numerous biological processes from covalent histone modification and DNA repair to specialized metabolism in plants and microorganisms. Enzymes that catalyze O- and N-demethylation include 2-oxoglutarate (2OG/Fe(II-dependent dioxygenases, cytochromes P450, Rieske-domain proteins and flavin adenine dinucleotide (FAD-dependent oxidases. Proposed mechanisms for demethylation by 2OG/Fe(II-dependent enzymes involve hydroxylation at the O- or N-linked methyl group followed by formaldehyde elimination. Members of this enzyme family catalyze a wide variety of reactions in diverse plant metabolic pathways. Recently, we showed that 2OG/Fe(II-dependent dioxygenases catalyze the unique O-demethylation steps of morphine biosynthesis in opium poppy, which provides a rational basis for the widespread occurrence of demethylases in benzylisoquinoline alkaloid metabolism.

  19. Pigeon NCL and NFL neuronal activity represents neural correlates of the sample.

    Science.gov (United States)

    Johnston, Melissa; Anderson, Catrona; Colombo, Michael

    2017-06-01

    Four birds were trained on a delayed matching-to-sample task with common outcomes where correct responses during both red and green trials yielded reward. We recorded neuronal activity from the avian nidopallium caudolaterale, the avian equivalent of the mammalian prefrontal cortex, and the avian nidopallium frontolaterale, a higher-order visual processing region. In both regions we found sustained activity during the delay period of both red and green trials. These findings provide the first evidence that delay activity in the pigeon's nidopallium caudolaterale and nidopallium frontolaterale represent a neural correlate for the to-be-remembered sample stimulus. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  20. Enantioselective accumulation of (--)-pinoresinol through O-demethylation of (+/-)-eudesmin by Aspergillus niger.

    Science.gov (United States)

    Kasahara, H; Miyazawa, M; Kameoka, H

    1997-04-01

    Microbial transformation of (+/-)-eudesmin by Aspergillus niger was investigated. Enantioselective accumulation of (--)-pinoresinol was shown through O-demethylation of (+/-)-eudesmin. This fungus O- demethylated both enantiomers of eudesmin, but the conversion rates for each enantiomer were clearly different.

  1. Anaerobic Mercury Methylation and Demethylation by Geobacter bemidjiensis Bem.

    Science.gov (United States)

    Lu, Xia; Liu, Yurong; Johs, Alexander; Zhao, Linduo; Wang, Tieshan; Yang, Ziming; Lin, Hui; Elias, Dwayne A; Pierce, Eric M; Liang, Liyuan; Barkay, Tamar; Gu, Baohua

    2016-04-19

    Microbial methylation and demethylation are two competing processes controlling the net production and bioaccumulation of neurotoxic methylmercury (MeHg) in natural ecosystems. Although mercury (Hg) methylation by anaerobic microorganisms and demethylation by aerobic Hg-resistant bacteria have both been extensively studied, little attention has been given to MeHg degradation by anaerobic bacteria, particularly the iron-reducing bacterium Geobacter bemidjiensis Bem. Here we report, for the first time, that the strain G. bemidjiensis Bem can mediate a suite of Hg transformations, including Hg(II) reduction, Hg(0) oxidation, MeHg production and degradation under anoxic conditions. Results suggest that G. bemidjiensis utilizes a reductive demethylation pathway to degrade MeHg, with elemental Hg(0) as the major reaction product, possibly due to the presence of genes encoding homologues of an organomercurial lyase (MerB) and a mercuric reductase (MerA). In addition, the cells can strongly sorb Hg(II) and MeHg, reduce or oxidize Hg, resulting in both time and concentration-dependent Hg species transformations. Moderate concentrations (10-500 μM) of Hg-binding ligands such as cysteine enhance Hg(II) methylation but inhibit MeHg degradation. These findings indicate a cycle of Hg methylation and demethylation among anaerobic bacteria, thereby influencing net MeHg production in anoxic water and sediments.

  2. Process for demethylating S-methyl-mercapto compounds

    NARCIS (Netherlands)

    Hansen, Theo; Jansen, Michael; van der Maarel, Marc

    1998-01-01

    PCT No. PCT/EP95/02883 Sec. 371 Date Jan. 8, 1997 Sec. 102(e) Date Jan. 8, 1997 PCT Filed Jul. 19, 1995 PCT Pub. No. WO96/03518 PCT Pub. Date Feb. 8, 1996The invention concerns a process for preparing mercapto compounds comprising the step of demethylating an S-methyl-mercapto compound of Formula I

  3. Process for demethylating S-methyl-mercapto compounds

    NARCIS (Netherlands)

    Hansen, Theo; Jansen, Michael; van der Maarel, Marc

    1998-01-01

    PCT No. PCT/EP95/02883 Sec. 371 Date Jan. 8, 1997 Sec. 102(e) Date Jan. 8, 1997 PCT Filed Jul. 19, 1995 PCT Pub. No. WO96/03518 PCT Pub. Date Feb. 8, 1996The invention concerns a process for preparing mercapto compounds comprising the step of demethylating an S-methyl-mercapto compound of Formula I

  4. A viable non-axisymmetric non-force-free field to represent solar active regions

    CERN Document Server

    Prasad, A

    2016-01-01

    A combination of analytical calculations and vectormagnetogram data are utilized to develop a non-axisymmetric non-force-free magnetic field and asses its viability in describing solar active regions. For the purpose, we construct a local spherical shell where a planar surface, tangential to the inner sphere, represents a Cartesian cutout of an active region. The magnetic field defined on the surface is then correlated with magnetograms. The analysis finds the non-axisymmetric non-force-free magnetic field, obtained by a superposition of two linear-force-free fields, correlates reasonably well with magnetograms.

  5. Associations between physical activity and other health behaviors in a representative sample of US adolescents.

    Science.gov (United States)

    Pate, R R; Heath, G W; Dowda, M; Trost, S G

    1996-11-01

    This study examined the associations between physical activity and other health behaviors in a representative sample of US adolescents. In the 1990 Youth Risk Behavior Survey, 11631 high school students provided information on physical activity; diet; substance use; and other negative health behaviors. Logistic regression analyses examined associations between physical activity and other health behaviors in a subset of 2652 high-active and 1641 low-active students. Low activity was associated with cigarette smoking, marijuana use, lower fruit and vegetable consumption, greater television watching, failure to wear a seat belt, and low perception of academic performance. For consumption of fruit, television watching, and alcohol consumption, significant interactions were found with race/ethnicity or sex, suggesting that sociocultural factors may affect the relationships between physical activity and some health behaviors. Low physical activity was associated with several other negative health behaviors in teenagers. Future studies should examine whether interventions for increasing physical activity in youth can be effective in reducing negative health behaviors.

  6. Involvement of mitochondria and caspase pathways in N-demethyl-clarithromycin-induced apoptosis in human cervical cancer HeLa cell

    Institute of Scientific and Technical Information of China (English)

    Ai-min QIAO; Takashi IKEJIMA; Shini-chi TASHIRO; Satoshi ONODERA; Wei-ge ZHANG; Ying-liang WU

    2006-01-01

    Aim: To study the mechanisms by which N-demethyl-clarithromycin (NDC) induces human cervical cancer HeLa cell apoptosis in vitro. Methods: The viability of N-demethyl-clarithromycin-induced HeLa cells was measured by MTT assay. Apoptotic cells with condensed nuclei were visualized by phase contrast microscopy. Nucleosomal DNA fragmentation was assayed by agarose gel electrophoresis. Measurement of mitochondrial transmembrane potential was analyzed by a FACScan flowcytometer. Caspase-3, poly-(ADP-ribose) polymerase (PARP), caspase-activated DNase (ICAD), Bcl-2, Bax, p53, and SIRT1 protein expression and the release of cytochrome c were detected by Western blot analysis. Results: N-demethyl-clarithromycin, an anti-inflammatory substance, inhibited HeLa cell growth in a dose- and time-dependent manner.N-demethyl-clarithromycin induced HeLa cell death through the apoptotic pathways. The pan-caspase inhibitor (z-VAD-fmk), caspase-3 inhibitor (z-DEVD-fmk) and the caspase-9 inhibitor (z-LEHD-fmk) partially enhanced cell viability induced by N-demethyl-clarithromycin, but the caspase-8 inhibitor (z-IETD-fmk) had almost no effect. Caspase-3 was activated then followed by the degradation of caspase-3 substrates, the inhibitor of ICAD and PARP. Simultaneously, mitochondrial transmembrane potential was markedly reduced and the release of cytochrome c in the cytosol was increased.N-demethyl-clarithromycin upregulated the expression ratio of mitochondrial Bax/Bcl-2, and significantly increased the expression of the p53 protein. It also downregulated anti-apoptotic protein SIRT1 expression. Conclusion: N-demethyl-clarithromycin induced apoptosis in HeLa cells via the mitochondrial pathway.

  7. Determination of representative nitrogen contents for the activity calculation of core components with respect to the C-14 activity

    Energy Technology Data Exchange (ETDEWEB)

    Kruse, Philipp [GNS Gesellschaft fuer Nuklear-Service mbH, Essen (Germany); Huettner, Frank [Vattenfall Europe Nuclear, Hamburg (Germany); Phlippen, Peter-Wilhelm [WTI GmbH, Juelich (Germany)

    2015-10-15

    For the final repository Konrad during operating and decommissioning phase, ten radionuclides and two radionuclide groups are restricted regarding their maximum storable activity quantities. One of the ten relevant radionuclides is C-14. The determination of the C-14 activities within activation calculations is currently performed with conservative assumptions. With the results of the presented analysis a method for a realistic determination of representative C-14 contents of irradiated steels is available now. The relevant N-14 contents as a source for the C-14 amount are lower than previously estimated.

  8. A suite of methods for representing activity space in a healthcare accessibility study

    Directory of Open Access Journals (Sweden)

    Gesler Wilbert M

    2005-10-01

    Full Text Available Abstract Background "Activity space" has been used to examine how people's habitual movements interact with their environment, and can be used to examine accessibility to healthcare opportunities. Traditionally, the standard deviational ellipse (SDE, a Euclidean measure, has been used to represent activity space. We describe the construction and application of the SDE at one and two standard deviations, and three additional network-based measures of activity space using common tools in GIS: the road network buffer (RNB, the 30-minute standard travel time polygon (STT, and the relative travel time polygon (RTT. We compare the theoretical and methodological assumptions of each measure, and evaluate the measures by examining access to primary care services, using data from western North Carolina. Results Individual accessibility is defined as the availability of healthcare opportunities within that individual's activity space. Access is influenced by the shape and area of an individual's activity space, the spatial distribution of opportunities, and by the spatial structures that constrain and direct movement through space; the shape and area of the activity space is partly a product of how it is conceptualized and measured. Network-derived measures improve upon the SDE by incorporating the spatial structures (roads that channel movement. The area of the STT is primarily influenced by the location of a respondent's residence within the road network hierarchy, with residents living near primary roads having the largest activity spaces. The RNB was most descriptive of actual opportunities and can be used to examine bypassing. The area of the RTT had the strongest correlation with a healthcare destination being located inside the activity space. Conclusion The availability of geospatial technologies and data create multiple options for representing and operationalizing the construct of activity space. Each approach has its strengths and limitations

  9. Movement-Related Sensorimotor High-Gamma Activity Mainly Represents Somatosensory Feedback

    Directory of Open Access Journals (Sweden)

    Seokyun Ryun

    2017-07-01

    Full Text Available Somatosensation plays pivotal roles in the everyday motor control of humans. During active movement, there exists a prominent high-gamma (HG >50 Hz power increase in the primary somatosensory cortex (S1, and this provides an important feature in relation to the decoding of movement in a brain-machine interface (BMI. However, one concern of BMI researchers is the inflation of the decoding performance due to the activation of somatosensory feedback, which is not elicited in patients who have lost their sensorimotor function. In fact, it is unclear as to how much the HG component activated in S1 contributes to the overall sensorimotor HG power during voluntary movement. With regard to other functional roles of HG in S1, recent findings have reported that these HG power levels increase before the onset of actual movement, which implies neural activation for top-down movement preparation or sensorimotor interaction, i.e., an efference copy. These results are promising for BMI applications but remain inconclusive. Here, we found using electrocorticography (ECoG from eight patients that HG activation in S1 is stronger and more informative than it is in the primary motor cortex (M1 regardless of the type of movement. We also demonstrate by means of electromyography (EMG that the onset timing of the HG power in S1 is later (49 ms than that of the actual movement. Interestingly, we show that the HG power fluctuations in S1 are closely related to subtle muscle contractions, even during the pre-movement period. These results suggest the following: (1 movement-related HG activity in S1 strongly affects the overall sensorimotor HG power, and (2 HG activity in S1 during voluntary movement mainly represents cortical neural processing for somatosensory feedback.

  10. Testing of SMA-enabled Active Chevron Prototypes under Representative Flow Conditions

    Science.gov (United States)

    Turner, Travis L.; Cabell,Randolph H.; Cano, Roberto J.; Silcox, Richard J.

    2008-01-01

    Control of jet noise continues to be an important research topic. Exhaust-nozzle chevrons have been shown to reduce jet noise, but parametric effects are not well understood. Additionally, thrust loss due to chevrons at cruise suggests significant benefit from active chevrons. The focus of this study is development of an active chevron concept for the primary purpose of parametric studies for jet noise reduction in the laboratory and secondarily for technology development to leverage for full scale systems. The active chevron concept employed in this work consists of a laminated composite structure with embedded shape memory alloy (SMA) actuators, termed a SMA hybrid composite (SMAHC). SMA actuators are embedded on one side of the neutral axis of the structure such that thermal excitation, via joule heating, generates a moment and deflects the structure. The performance of two active chevron concepts is demonstrated in the presence of representative flow conditions. One of the concepts is shown to possess significant advantages for the proposed application and is selected for further development. Fabrication and design changes are described and shown to produce a chevron prototype that meets the performance objectives.

  11. Eastern region represents a worrying cluster of active hepatitis C in Algeria in 2012.

    Science.gov (United States)

    Bensalem, Aïcha; Selmani, Karima; Hihi, Narjes; Bencherifa, Nesrine; Mostefaoui, Fatma; Kerioui, Cherif; Pineau, Pascal; Debzi, Nabil; Berkane, Saadi

    2016-08-01

    Algeria is the largest country of Africa, peopled with populations living a range of traditional/rural and modern/urban lifestyles. The variations of prevalence of chronic active hepatitis care poorly known on the Algerian territory. We conducted a retrospective survey on all patients (n = 998) referred to our institution in 2012 and confirmed by us for an active hepatitis C. Half of the hepatitis C virus (HCV) isolates were genotyped. Forty Algerian regions out of the 48 were represented in our study. Three geographical clusters (Aïn-Temouchent/SidiBelAbbes, Algiers, and a large Eastern region) with an excess of active hepatitis C were observed. Patients coming from the Eastern cluster (Batna, Khenchela, Oum el Bouaghi, and Tebessa) were strongly over-represented (49% of cases, OR = 14.5, P < 0.0001). The hallmarks of Eastern region were an excess of women (65% vs. 46% in the remaining population, P < 0.0001) and the almost exclusive presence of HCV genotype 1 (93% vs. 63%, P = 0.0001). The core of the epidemics was apparently located in Khenchela (odds ratio = 24.6, P < 0.0001). This situation is plausibly connected with nosocomial transmission or traditional practices as scarification (Hijama), piercing or tattooing, very lively in this region. Distinct hepatitis C epidemics are currently affecting Algerian population. The most worrying situation is observed in rural regions located east of Algeria. J. Med. Virol. 88:1394-1403, 2016. © 2016 Wiley Periodicals, Inc.

  12. Glycogen synthase kinase-3β regulates leucine-309 demethylation of protein phosphatase-2A via PPMT1 and PME-1.

    Science.gov (United States)

    Yao, Xiu-Qing; Li, Xia-Chun; Zhang, Xiao-Xue; Yin, Yang-Yang; Liu, Bin; Luo, Dan-Ju; Wang, Qun; Wang, Jian-Zhi; Liu, Gong-Ping

    2012-07-30

    Protein phosphatase-2A (PP2A) activity is significantly suppressed in Alzheimer's disease. We have reported that glycogen synthase kinase-3β (GSK-3β) inhibits PP2A via upregulating the phosphorylation of PP2A catalytic subunit (PP2A(C)). Here we studied the effects of GSK-3β on the inhibitory demethylation of PP2A at leucine-309 (dmL309-PP2A(C)). We found that GSK-3β regulates dmL309-PP2A(C) level by regulating PME-1 and PPMT1. Knockdown of PME-1 or PPMT1 eliminated the effects of GSK-3β on PP2A(C). GSK-3 could negatively regulate PP2A regulatory subunit protein level. We conclude that GSK-3β can inhibit PP2A by increasing the inhibitory L309-demethylation involving upregulation of PME-1 and inhibition of PPMT1.

  13. Demethylation effect of the antineoplaston AS2-1 on genes in colon cancer cells

    Science.gov (United States)

    USHIJIMA, MASATAKA; OGATA, YUTAKA; TSUDA, HIDEAKI; AKAGI, YOSHITO; MATONO, KEIKO; SHIROUZU, KAZUO

    2014-01-01

    Antineoplastons are naturally occurring peptides and amino acid derivatives found in human blood and urine. Antineoplastons have been shown to control neoplastic growth. In the present study, we investigated demethylation effect of the antineoplaston AS2-1 (a mixture of phenylacetylglutamine and phenylacetate in the ratio of 1:4) on various genes in colon cancer cells. An HpaII-MspI methylation microarray was used to investigate the methylation status of 51 genes at the promoter region in HCT116 and KM12SM human colon cancer cells before and after treatment of AS2-1. The expression of protein and mRNA of the demethylated genes by AS2-1 in HCT116 cells was evaluated. In 19 of the 34 methylated genes in HCT116 and in 7 of the 8 methylated genes in KM12SM, the methylation status was downregulated after treatment with 2 mg/ml of AS2-1 for 24 h. AS2-1 dramatically downregulated the methylation status of p15 and ESR1 in HCT116 cells and of MTHFR and MUC2 in KM12SM cells. Both mRNA and protein expression of p15 increased in a dose- and time-dependent manner after treatment with AS2-1. The antineoplaston AS2-1 may normalize the hypermethylation status at the promoter region in various genes including tumor suppressor genes, resulting in activation of the transcription and translation in colon cancer. PMID:24213840

  14. Using McDaniel's model to represent non-Rayleigh active sonar reverberation

    Science.gov (United States)

    Gu, Ming

    Reverberation in active sonar systems has often been observed to follow non-Rayleigh distributions. Current statistical models tend to be either too restrictive, leading to significant mismatch error, or too general, leading to large estimation error. McDaniel's model has shown promise as having reasonably tight representation in terms of skewness and kurtosis for reverberation from a variety of sonar systems. This dissertation intensively explores capability and effectiveness of the generalized McDaniel's model in representing non-Rayleigh reverberation when minimal data are available. Three major topics are covered in this dissertation. First, derivation and computation of the cumulative distribution function of McDaniel's model is addressed. Two approaches, one based on direct integration and the other via characteristic function inversion, are both shown to achieve adequate precision with the former leading to a closed-form solution and the latter requiring significantly less computational effort. Second, parameter estimators using both method of moments (MM) and maximum likelihood (ML) algorithms are developed. The MM estimator has the advantage of a simple and rapid implementation, but the disadvantage of a non- zero probability of a solution not existing. Bootstrap/pruning techniques are proposed to partially deal with the failure of this method. The ML estimator will always provide a solution; however, it requires multivariate optimization. The expectation-maximization (EM) algorithm iteration is also derived for obtaining the ML estimates and compared with the simplex method and quasi-Newton multivariate optimization routines. Furthermore, the ability of various statistical models to represent the probability of false alarm is evaluated as a function of sample size. It is demonstrated that when minimal data are available, McDaniel's model can more accurately represent non-Rayleigh reverberation than the K or Rayleigh mixture models. Third, detection

  15. Genome-wide Bisulfite Sequencing in Zygotes Identifies Demethylation Targets and Maps the Contribution of TET3 Oxidation

    Directory of Open Access Journals (Sweden)

    Julian R. Peat

    2014-12-01

    Full Text Available Fertilization triggers global erasure of paternal 5-methylcytosine as part of epigenetic reprogramming during the transition from gametic specialization to totipotency. This involves oxidation by TET3, but our understanding of its targets and the wider context of demethylation is limited to a small fraction of the genome. We employed an optimized bisulfite strategy to generate genome-wide methylation profiles of control and TET3-deficient zygotes, using SNPs to access paternal alleles. This revealed that in addition to pervasive removal from intergenic sequences and most retrotransposons, gene bodies constitute a major target of zygotic demethylation. Methylation loss is associated with zygotic genome activation and at gene bodies is also linked to increased transcriptional noise in early development. Our data map the primary contribution of oxidative demethylation to a subset of gene bodies and intergenic sequences and implicate redundant pathways at many loci. Unexpectedly, we demonstrate that TET3 activity also protects certain CpG islands against methylation buildup.

  16. Green tea polyphenol EGCG reverse cisplatin resistance of A549/DDP cell line through candidate genes demethylation.

    Science.gov (United States)

    Zhang, Youwei; Wang, Xiang; Han, Liang; Zhou, Yizhou; Sun, Sanyuan

    2015-02-01

    Epigallocatechin-3-gallate (EGCG), the major polyphenol in green tea, has been extensively studied as a potential demethylating agent. Our hypothesis is that EGCG could resensitize non-small-cell lung cancer (NSCLC) cells to cisplatin (DDP) through candidate genes demethylation. The A549/DDP cell line was established by continuous exposure of A549 cells to increasing concentrations of DDP. MTT, colony formation assay, flow cytometric analysis, Hoechst staining, real time-PCR, quantitative methylation-specific PCR and in vivo experiments were performed in this study. EGCG+DDP treatment significantly caused proliferation inhibition, cell cycle arrest in G1 phase, increase of apoptosis in A549/DDP cells, along with inhibition of DNA methyltransferase (DNMT) activity and histone deacetylase (HDAC) activity, reversal of hypermethylated status and downregulated expression of GAS1, TIMP4, ICAM1 and WISP2 gene in A549/DDP cells. Furthermore, pre-treatment with EGCG followed by DDP caused significant tumor inhibition in vivo. Methylation levels of GAS1, TIMP4, ICAM1 and WISP2 were decreased and their expression levels were increased in EGCG-treatment groups, but only combinatorial treatment group caused growth inhibition. In conclusion, we identified EGCG pretreatment resensitized cells to DDP, along with the demethylation and restoration of expression of candidate genes.

  17. Poly(ADP-ribosylation acts in the DNA demethylation of mouse primordial germ cells also with DNA damage-independent roles.

    Directory of Open Access Journals (Sweden)

    Fabio Ciccarone

    Full Text Available Poly(ADP-ribosylation regulates chromatin structure and transcription driving epigenetic events. In particular, Parp1 is able to directly influence DNA methylation patterns controlling transcription and activity of Dnmt1. Here, we show that ADP-ribose polymer levels and Parp1 expression are noticeably high in mouse primordial germ cells (PGCs when the bulk of DNA demethylation occurs during germline epigenetic reprogramming in the embryo. Notably, Parp1 activity is stimulated in PGCs even before its participation in the DNA damage response associated with active DNA demethylation. We demonstrate that PARP inhibition impairs both genome-wide and locus-specific DNA methylation erasure in PGCs. Moreover, we evidence that impairment of PARP activity causes a significant reduction of expression of the gene coding for Tet1 hydroxylases involved in active DNA demethylation. Taken together these results demonstrate new and adjuvant roles of poly(ADP-ribosylation during germline DNA demethylation and suggest its possible more general involvement in genome reprogramming.

  18. CYP2C subfamily, primarily CYP2C9, catalyses the enantioselective demethylation of the endocrine disruptor pesticide methoxychlor in human liver microsomes: use of inhibitory monoclonal antibodies in P450 identification.

    Science.gov (United States)

    Hu, Y; Krausz, K; Gelboin, H V; Kupfer, D

    2004-02-01

    1. The endocrine disruptor pesticide methoxychlor undergoes O-demethylation by mammalian liver microsomes forming chiral mono-phenolic (1,1,1-trichloro-2-(4-hydroxyphenyl)-2-(4-methoxyphenyl)ethane, i.e. mono-OH-M) and achiral bis-phenolic oestrogenic metabolites. Human liver microsomes (HLM) generated primarily the S-mono-OH-M. 2. Inhibitory monoclonal antibodies (MAb) identified those P450s catalysing the enantioselective O-demethylation of methoxychlor. In HLM, O-demethylation was inhibited by MAb anti-2C9 (30-40%), diminishing the per cent of S-mono-OH-M from about 80 to 55-60%. MAb anti-CYP1A2, 2A6, 2B6, 2C8, 2C19, 2D6 and 3A4 did not affect the demethylation rate in HLM. Nevertheless, MAb anti-CYP1A2 decreased the formation of R-mono-OH-M from 21-23 to 10-17%, indicating that CYP1A2 exhibits a role in generating the R-enantiomer. 3. Among cDNA-expressed human P450s (supersomes), CYP2C19 was the most active in demethylation, but in HLM, CYP2C19 appeared inactive (no inhibition by MAb anti-CYP2C19). There was a substantial difference in the per cent inhibition of demethylation by MAb anti-CYP2C9 and anti-rat CYP2C (MAb inhibiting all human CYP2C forms) and in altering the enantioselectivity, suggesting that demethylation by combined CYP2C8, 2C18 and 2C19 was significant (20-30%). 4. Polymorphism of methoxychlor demethylation was examined with supersomes and HLM-expressing CYP2C9 allelic variants. CYP2C9*1 and 2C9*2 were highly active; however, CYP2C9*3 appeared inactive.

  19. Mitochondrial DNA copy number is regulated by DNA methylation and demethylation of POLGA in stem and cancer cells and their differentiated progeny.

    Science.gov (United States)

    Lee, W; Johnson, J; Gough, D J; Donoghue, J; Cagnone, G L M; Vaghjiani, V; Brown, K A; Johns, T G; St John, J C

    2015-02-26

    Mitochondrial DNA (mtDNA) copy number is strictly regulated during differentiation so that cells with a high requirement for ATP generated through oxidative phosphorylation have high mtDNA copy number, whereas those with a low requirement have few copies. Using immunoprecipitation of DNA methylation on 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC), which distinguish between de novo DNA methylation and demethylation, respectively, we set out to determine whether DNA methylation at exon 2 of the human mtDNA-specific polymerase (DNA polymerase gamma A (POLGA)) regulates cell-specific mtDNA copy number in highly proliferative and terminally differentiated cells. Highly proliferative cancer and pluripotent and multipotent cells possessed low mtDNA copy number and were highly methylated at exon 2 of POLGA in contrast to post-mitotic cells. Unlike neural stem cells, cancer cells were unable to differentiate and remained extensively DNA methylated at exon 2 of POLGA. However, mtDNA depletion of cancer cells reduced DNA methylation at exon 2 of POLGA as they replenished mtDNA to form tumours in mice. Glioblastoma cells treated with the DNA demethylation agent 5-azacytidine over 28 days of astrocyte-induced differentiation demethylated exon 2 of POLGA leading to increased mtDNA copy number and expression of the astrocyte endpoint marker glial fibrillary acidic protein (GFAP). However, the demethylation agent vitamin C (VitC) was unable to sustain increased mtDNA copy number and differentiation, as was the case when VitC was withdrawn after short-term treatment. These data demonstrate that DNA demethylation of POLGA is an essential regulator of mtDNA copy number and cellular fate and that cancer cells are only able to modulate DNA methylation of POLGA and mtDNA copy number in the presence of a DNA demethylation agent that inhibits de novo methyltransferase 1 activity.

  20. Redistribution of demethylated RNA helicase A during foot-and-mouth disease virus infection: Role of Jumonji C-domain containing protein 6 in RHA demethylation

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, Paul; Conderino, Joseph S.; Rieder, Elizabeth, E-mail: elizabeth.rieder@ars.usda.gov

    2014-03-15

    Previously, RNA helicase A (RHA) re-localization from the nucleus to the cytoplasm in foot-and-mouth disease virus (FMDV) infected cells was shown to coincide with loss of RHA methylated arginine residues at its C-terminus. The potential interaction between RHA and Jumonji C-domain (JmjC) protein 6 (JMJD6) arginine demethylase in infected cells was investigated. Treatment with N-oxalylglycine (NOG) inhibitor of JmjC demethylases prevented FMDV-induced RHA demethylation and re-localization, and also decreased viral protein synthesis and virus titers. Physical interaction between JMJD6 and RHA was demonstrated via reciprocal co-immunoprecipitation, where RHA preferentially bound JMJD6 monomers. Nuclear efflux of demethylated RHA (DM-RHA) coincided with nuclear influx of JMJD6, which was not observed using another picornavirus. A modified biochemical assay demonstrated JMJD6 induced dose-dependent demethylation of RHA and two RHA-derived isoforms, which could be inhibited by NOG. We propose a role for JMJD6 in RHA demethylation stimulated by FMDV, that appears to facilitate virus replication. - Highlights: • We examined the role of JMJD6 in FMDV-induced RHA demethylation process. • Using an arginine demethylation assay showed that JMJD6 is involved in RHA demethylation. • A demethylases inhibitor reduced cytoplasmic accumulation of RHA and FMDV titers.

  1. 5-hydroxymethylcytosine-mediated DNA demethylation in stem cells and development.

    Science.gov (United States)

    Sun, Wenjia; Guan, Minxin; Li, Xuekun

    2014-05-01

    The pursuit of DNA demethylation has a colorful history, but it was not until 2009 that the stars of this story, the Ten-eleven-translocation (Tet) family of proteins, were really identified. Tet proteins convert 5-methylcytosine to 5-hydroxymethylcytosine (5hmC), which can be further oxidized to 5-formylcytosine and 5-cyboxycytosine by Tet proteins to achieve DNA demethylation. Recent studies have revealed that 5hmC-mediated DNA demethylation can play essential roles in diverse biological processes, including development and diseases. Here, we review recent discoveries in 5hmC-mediated DNA demethylation in the context of stem cells and development.

  2. Acute hypersensitivity of pluripotent testicular cancer-derived embryonal carcinoma to low-dose 5-aza deoxycytidine is associated with global DNA Damage-associated p53 activation, anti-pluripotency and DNA demethylation.

    Directory of Open Access Journals (Sweden)

    Bijesh K Biswal

    Full Text Available Human embryonal carcinoma (EC cells are the stem cells of nonseminoma testicular germ cells tumors (TGCTs and share remarkable similarities to human embryonic stem (ES cells. In prior work we found that EC cells are hypersensitive to low nanomolar doses of 5-aza deoxycytidine (5-aza and that this hypersensitivity partially depended on unusually high levels of the DNA methyltransferase, DNMT3B. We show here that low-dose 5-aza treatment results in DNA damage and induction of p53 in NT2/D1 cells. In addition, low-dose 5-aza results in global and gene specific promoter DNA hypomethylation. Low-dose 5-aza induces a p53 transcriptional signature distinct from that induced with cisplatin in NT2/D1 cells and also uniquely downregulates genes associated with pluripotency including NANOG, SOX2, GDF3 and Myc target genes. Changes in the p53 and pluripotency signatures with 5-aza were to a large extent dependent on high levels of DNMT3B. In contrast to the majority of p53 target genes upregulated by 5-aza that did not show DNA hypomethylation, several other genes induced with 5-aza had corresponding decreases in promoter methylation. These genes include RIN1, SOX15, GPER, and TLR4 and are novel candidate tumors suppressors in TGCTs. Our studies suggest that the hypersensitivity of NT2/D1 cells to low-dose 5-aza is multifactorial and involves the combined activation of p53 targets, repression of pluripotency genes, and activation of genes repressed by DNA methylation. Low-dose 5-aza therapy may be a general strategy to treat those tumors that are sustained by cells with embryonic stem-like properties.GEO NUMBER FOR THE MICROARRAY DATA: GSE42647.

  3. Do Public Involvement Activities in Biomedical Research and Innovation Recruit Representatively? A Systematic Qualitative Review.

    Science.gov (United States)

    Lander, Jonas; Hainz, Tobias; Hirschberg, Irene; Bossert, Sabine; Strech, Daniel

    2016-01-01

    Public involvement activities (PIAs) may contribute to the governance of ethically challenging biomedical research and innovation by informing, consulting with and engaging the public in developments and decision-making processes. For PIAs to capture a population's preferences (e.g. on issues in whole genome sequencing, biobanks or genome editing), a central methodological requirement is to involve a sufficiently representative subgroup of the general public. While the existing literature focusses on theoretical and normative aspects of 'representation', this study assesses empirically how such considerations are implemented in practice. It evaluates how PIA reports describe representation objectives, the recruitment process and levels of representation achieved. PIA reports were included from a systematic literature search if they directly reported a PIA conducted in a relevant discipline such as genomics, biobanks, biotechnology or others. PIA reports were analyzed with thematic text analysis. The text analysis was guided by an assessment matrix based on PIA-specific guidelines and frameworks. We included 46 relevant reports, most focusing on issues in genomics. 27 reports (59%) explicitly described representation objectives, though mostly without adjusting eligibility criteria and recruiting methods to the specific objective. 11 reports (24%) explicitly reported to have achieved the intended representation; the rest either reported failure or were silent on this issue. Representation of study samples in PIAs in biomedical research and innovation is currently not reported systematically. Improved reporting on representation would not only improve the validity and value of PIAs, but could also contribute to PIA results being used more often in relevant policy and decision-making processes. © 2016 S. Karger AG, Basel.

  4. Cytochrome P4502D6 catalyzes the O-demethylation of the psychoactive alkaloid ibogaine to 12-hydroxyibogamine.

    Science.gov (United States)

    Obach, R S; Pablo, J; Mash, D C

    1998-08-01

    Ibogaine is a psychoactive alkaloid that possesses potential as an agent to treat opiate and cocaine addiction. The primary metabolite arises via O-demethylation at the 12-position to yield 12-hydroxyibogamine. In this report, evidence is presented that the O-demethylation of ibogaine observed in human hepatic microsomes is catalyzed primarily by the polymorphically expressed cytochrome P-4502D6 (CYP2D6). An enzyme kinetic examination of ibogaine O-demethylase activity in pooled human liver microsomes suggested that two (or more) enzymes are involved in this reaction: one with a low KMapp (1.1 microM) and the other with a high KMapp (>200 microM). The low KMapp activity comprised >95% of total intrinsic clearance. Human liver microsomes from three individual donors demonstrated similar enzyme kinetic parameters (mean KMapp = 0.55 +/- 0.09 microM and 310 +/- 10 microM for low and high KM activities, respectively). However, a fourth human microsome sample that appeared to be a phenotypic CYP2D6 poor metabolizer possessed only the high KMapp activity. In hepatic microsomes from a panel of human donors, the low KMapp ibogaine O-demethylase activity correlated with CYP2D6-catalyzed bufuralol 1'-hydroxylase activity but not with other P450 isoform-specific activities. Quinidine, a CYP2D6-specific inhibitor, inhibited ibogaine O-demethylase (IC50 = 0.2 microM), whereas other P450 isoform-specific inhibitors did not inhibit this activity. Also, of a battery of recombinant heterologously expressed human P450 isoforms, only rCYP2D6 possessed significant ibogaine O-demethylase activity. Thus, it is concluded that ibogaine O-demethylase is catalyzed by CYP2D6 and that this isoform is the predominant enzyme of ibogaine O-demethylation in humans. The potential pharmacological implications of these findings are discussed.

  5. Inhibitors of DNA Methylation, Histone Deacetylation, and Histone Demethylation: A Perfect Combination for Cancer Therapy.

    Science.gov (United States)

    Zahnow, C A; Topper, M; Stone, M; Murray-Stewart, T; Li, H; Baylin, S B; Casero, R A

    2016-01-01

    Epigenetic silencing and inappropriate activation of gene expression are frequent events during the initiation and progression of cancer. These events involve a complex interplay between the hypermethylation of CpG dinucleotides within gene promoter and enhancer regions, the recruitment of transcriptional corepressors and the deacetylation and/or methylation of histone tails. These epigenetic regulators act in concert to block transcription or interfere with the maintenance of chromatin boundary regions. However, DNA/histone methylation and histone acetylation states are reversible, enzyme-mediated processes and as such, have emerged as promising targets for cancer therapy. This review will focus on the potential benefits and synergistic/additive effects of combining DNA-demethylating agents and histone deacetylase inhibitors or lysine-specific demethylase inhibitors together in epigenetic therapy for solid tumors and will highlight what is known regarding the mechanisms of action that contribute to the antitumor response.

  6. A probabilistic generative model for quantification of DNA modifications enables analysis of demethylation pathways.

    Science.gov (United States)

    Äijö, Tarmo; Huang, Yun; Mannerström, Henrik; Chavez, Lukas; Tsagaratou, Ageliki; Rao, Anjana; Lähdesmäki, Harri

    2016-03-14

    We present a generative model, Lux, to quantify DNA methylation modifications from any combination of bisulfite sequencing approaches, including reduced, oxidative, TET-assisted, chemical-modification assisted, and methylase-assisted bisulfite sequencing data. Lux models all cytosine modifications (C, 5mC, 5hmC, 5fC, and 5caC) simultaneously together with experimental parameters, including bisulfite conversion and oxidation efficiencies, as well as various chemical labeling and protection steps. We show that Lux improves the quantification and comparison of cytosine modification levels and that Lux can process any oxidized methylcytosine sequencing data sets to quantify all cytosine modifications. Analysis of targeted data from Tet2-knockdown embryonic stem cells and T cells during development demonstrates DNA modification quantification at unprecedented detail, quantifies active demethylation pathways and reveals 5hmC localization in putative regulatory regions.

  7. The Cell Cycle: An Activity Using Paper Plates to Represent Time Spent in Phases of the Cell Cycle

    Science.gov (United States)

    Scherer, Yvette D.

    2014-01-01

    In this activity, students are given the opportunity to combine skills in math and geometry for a biology lesson in the cell cycle. Students utilize the data they collect and analyze from an online onion-root-tip activity to create a paper-plate time clock representing a 24-hour cell cycle. By dividing the paper plate into appropriate phases of…

  8. The Cell Cycle: An Activity Using Paper Plates to Represent Time Spent in Phases of the Cell Cycle

    Science.gov (United States)

    Scherer, Yvette D.

    2014-01-01

    In this activity, students are given the opportunity to combine skills in math and geometry for a biology lesson in the cell cycle. Students utilize the data they collect and analyze from an online onion-root-tip activity to create a paper-plate time clock representing a 24-hour cell cycle. By dividing the paper plate into appropriate phases of…

  9. Decreased electrophysiological activity represents the conscious state of emptiness in meditation

    OpenAIRE

    Thilo eHinterberger; Stephanie eSchmidt; Tsutomu eKamei; Harald eWalach

    2014-01-01

    Many neuroscientific theories explain consciousness with higher order information processing corresponding to an activation of specific brain areas and processes. In contrast, most forms of meditation ask for a down-regulation of certain mental processing activities while remaining fully conscious. To identify the physiological properties of conscious states with decreased mental and cognitive processing, the electrical brain activity (64 channels of EEG) of 50 participants of various meditat...

  10. Mercury Methylation, Demethylation, and Bioavailability in the Hyporheic Sediments of a Northern Wisconsin Wetland

    Science.gov (United States)

    Creswell, J. E.; Babiarz, C. L.; Shafer, M. M.; Roden, E. E.; Armstrong, D. E.

    2007-12-01

    It is generally accepted that wetland sediments have a high potential to produce methylmercury, yet the factors controlling the relevant chemical transformations are poorly understood. Previous studies suggest that sulfate- reducing bacteria play an important role in methylation, but iron-reducing bacteria may also participate in this process. Methylation rates are influenced by both the concentration of Hg(II) and its speciation, which affects its bioavailability. Net accumulation depends also on demethylation rates, rates which may be significant in these systems. The objective of this study is to gain a better understanding of the main factors controlling the bioavailability of inorganic mercury for the production of methylmercury in wetland hyporheic zones. Stable isotopes of mercury are being used to investigate potential methylation and demethylation rates in the hyporheic sediments of Allequash Creek, near Boulder Junction, WI. Other techniques that are being applied to examine the chemical and biological drivers of mercury methylation and bioavailability include tin-reducible mercury "titrations" to measure the concentration of strong mercury-binding ligands in porewater, 14C-acetate uptake assays to determine the activity of the native microbial consortia , ion exchange resin experiments to explore the role of dissolved organic carbon in mercury binding, and inhibition studies (e.g. molybdenum amendments) of sulfate-reducing bacteria to assess their role in producing methylmercury. Manipulations of environmental conditions in laboratory microcosms are used to determine the relative importance of physical factors, such as temperature, and biogeochemical factors, such as sulfate, sulfide, dissolved organic carbon (DOC), and iron levels, on the fate of mercury in hyporheic systems. Preliminary results show that while significant levels of inorganic mercury are present in the hyporheic groundwater, strong mercury-binding ligands in the wetland porewaters at a

  11. Extracurricular Activities and Bullying Perpetration: Results From a Nationally Representative Sample.

    Science.gov (United States)

    Riese, Alison; Gjelsvik, Annie; Ranney, Megan L

    2015-08-01

    Bullying is a widespread problem for school-aged children and adolescents. Interventions to reduce bullying are not well disseminated. Extracurricular involvement is, however, common. This study aims to examine the relationship between parent-reported participation in extracurricular activities and bullying perpetration. Using the 2011 National Survey of Children's Health, 62,215 interviews with parents of children 6 to 17 were analyzed. Extracurricular categories of sports only, sports + nonsport, nonsport only, and no activities were based on parental response to questions regarding sport teams/lessons, clubs, and organizations. Bullying was derived from report of the child "bullying or being cruel/mean to others." Weighted bivariate analyses, logistic regression, and sex/race/ethnicity/age stratified analyses were conducted. Eighty percent of children participated in extracurricular activities: 8% sports, 48% sports + nonsports, and 24% nonsports. Bullying perpetration was reported in 15% of the sample. Compared with those not participating in extracurricular activities, the odds of bullying were significantly lower for children who participated in sports + nonsports (Adjusted odds ratio (AOR) 0.67, 95% confidence interval [CI] 0.57-0.79) and nonsport only (AOR 0.82, 95% CI 0.70-0.97). Stratified analyses showed attenuated effects of extracurricular activities for boys and for Hispanics. Children who participate in a variety of extracurricular activities exhibit the least frequent bullying perpetration. © 2015, American School Health Association.

  12. Association Between User-Generated Commuting Data and Population-Representative Active Commuting Surveillance Data - Four Cities, 2014-2015.

    Science.gov (United States)

    Whitfield, Geoffrey P; Ussery, Emily N; Riordan, Brian; Wendel, Arthur M

    2016-09-16

    Creating environments that support all types of physical activity, including active transportation, is a public health priority (1). Public health surveillance that identifies the locations where community members walk and bicycle (i.e., engage in active transportation) can inform such efforts. Traditional population-representative active transportation surveillance incurs a considerable time lag between data collection and dissemination, and often lacks geographic specificity (2). Conversely, user-generated active transportation data from Global Positioning System (GPS)-based activity tracking devices and mobile applications can provide near real-time information, but might be subject to self-selection bias among users. CDC analyzed the association between GPS-based commuting data from a company that allows tracking of activity with a mobile application (Strava, Inc., San Francisco, California) and population-representative commuting data from the U.S. Census Bureau's American Community Survey (ACS) (3) for four U.S. cities. The level of analysis was the Census block group. The number of GPS-tracked commuters in Strava was associated with the number of ACS active commuters (Spearman's rho = 0.60), suggesting block groups were ranked similarly based on these distinct but related measurements. The correlation was higher in high population density areas. User-generated active transportation data might complement traditional surveillance systems by providing near real-time, location-specific information on where active transportation occurs.

  13. Decreased electrophysiological activity represents the conscious state of emptiness in meditation.

    Science.gov (United States)

    Hinterberger, Thilo; Schmidt, Stephanie; Kamei, Tsutomu; Walach, Harald

    2014-01-01

    Many neuroscientific theories explain consciousness with higher order information processing corresponding to an activation of specific brain areas and processes. In contrast, most forms of meditation ask for a down-regulation of certain mental processing activities while remaining fully conscious. To identify the physiological properties of conscious states with decreased mental and cognitive processing, the electrical brain activity (64 channels of EEG) of 50 participants of various meditation proficiencies was measured during distinct and idiosyncratic meditative tasks. The tasks comprised a wakeful "thoughtless emptiness (TE)," a "focused attention," and an "open monitoring" task asking for mindful presence in the moment and in the environment without attachment to distracting thoughts. Our analysis mainly focused on 30 highly experienced meditators with at least 5 years and 1000 h of meditation experience. Spectral EEG power comparisons of the TE state with the resting state or other forms of meditation showed decreased activities in specific frequency bands. In contrast to a focused attention task the TE task showed significant central and parietal gamma decreases (p waves than a wakeful closed eyes resting condition. A group of participants with none or little meditation practice did not present those differences significantly. Our findings indicate that a conscious state of TE reached by experienced meditators is characterized by reduced high-frequency brain processing with simultaneous reduction of the low frequencies. This suggests that such a state of meditative conscious awareness might be different from higher cognitive and mentally focused states but also from states of sleep and drowsiness.

  14. Decreased Electrophysiological Activity Represents the Conscious State of Emptiness in Meditation

    Directory of Open Access Journals (Sweden)

    Thilo eHinterberger

    2014-02-01

    Full Text Available Many neuroscientific theories explain consciousness with higher order information processing corresponding to an activation of specific brain areas and processes. In contrast, most forms of meditation ask for a down-regulation of certain mental processing activities while remaining fully conscious. To identify the physiological properties of conscious states with decreased mental and cognitive processing, the electrical brain activity (64 channels of EEG of 50 participants of various meditation proficiencies was measured during distinct and idiosyncratic meditative tasks. The tasks comprised a wakeful ‘thoughtless emptiness (TE’, a ‘focused attention’, and an ‘open monitoring’ task asking for mindful presence in the moment and in the environment without attachment to distracting thoughts. Our analysis mainly focused on 30 highly experienced meditators with at least 5 years and 1000 hours of meditation experience.Spectral EEG power comparisons of the TE state with the resting state or other forms of meditation showed decreased activities in specific frequency bands. In contrast to a focused attention task the TE task showed significant central and parietal gamma decreases (pOur findings indicate that a conscious state of thoughtless emptiness reached by experienced meditators is characterized by reduced high-frequency brain processing with simultaneous reduction of the low frequencies. This suggests that such a state of meditative conscious awareness might be different from higher cognitive and mentally focused states but also from states of sleep and drowsiness.

  15. Experience dependent development of coordinated hippocampal spatial activity representing the similarity of related locations

    Science.gov (United States)

    Singer, Annabelle C.; Karlsson, Mattias P.; Nathe, Ana R.; Carr, Margaret F.; Frank, Loren M.

    2010-01-01

    To learn we must identify and remember experiences uniquely but also generalize across experiences to extract common features. Hippocampal place cells can show similar firing patterns across locations, but the functional significance of this repetitive activity and the role of experience and learning in generating it are not understood. We therefore examined rat hippocampal place cell activity in the context of spatial tasks with multiple similar spatial trajectories. We found that, in environments with repeating elements, about half of the recorded place cells showed path equivalent firing where individual neurons are active in multiple similar locations. In contrast, place cells from animals performing a similar task in an environment with fewer similar elements were less likely to fire in a path equivalent manner. Moreover, in the environment with multiple repeating elements, path equivalence developed with experience in the task and increased path equivalence was associated with increased moment-by-moment correlations between pairs of path equivalent neurons. As a result, correlated firing among path equivalent neurons increased with experience. These findings suggest that coordinated hippocampal ensembles can encode generalizations across locations. Thus, path equivalent ensembles are well suited to encode similarities among repeating elements, providing a framework for associating specific behaviors with multiple locations, while neurons without this repetitive structure maintain a distinct population code. PMID:20810880

  16. Rhythmic delta activity represents a form of nonconvulsive status epilepticus in anti-NMDA receptor antibody encephalitis.

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    Kirkpatrick, McNeill P; Clarke, Charles D; Sonmezturk, Hasan H; Abou-Khalil, Bassel

    2011-02-01

    Anti-NMDA receptor antibody encephalitis is a limbic encephalitis with psychiatric manifestations, abnormal movements, coma, and seizures. The coma and abnormal movements are not typically attributed to seizure activity, and slow activity is the most common EEG finding. We report drug-resistant nonconvulsive status epilepticus as the basis for coma in a 19-year-old woman with anti-NMDA receptor antibodies and a mediastinal teratoma. The EEG showed generalized rhythmic delta activity, with evolution in morphology, frequency, and field typical of nonconvulsive status epilepticus. The status was refractory to antiepileptic drugs, repeated drug-induced coma, resection of the tumor, intravenous steroids, rituximab, and plasmapheresis. She awoke after the addition of felbamate, and the rhythmic delta activity ceased. The rhythmic delta activity described with coma in anti-NMDA receptor antibody encephalitis may represent a pattern of status epilepticus in some patients. Felbamate, which has NMDA receptor antagonist activity, should be studied as a therapeutic agent in this condition.

  17. The CYP2B6*6 allele significantly alters the N-demethylation of ketamine enantiomers in vitro.

    Science.gov (United States)

    Li, Yibai; Coller, Janet K; Hutchinson, Mark R; Klein, Kathrin; Zanger, Ulrich M; Stanley, Nathan J; Abell, Andrew D; Somogyi, Andrew A

    2013-06-01

    Ketamine is primarily metabolized to norketamine by hepatic CYP2B6 and CYP3A4-mediated N-demethylation. However, the relative contribution from each enzyme remains controversial. The CYP2B6*6 allele is associated with reduced enzyme expression and activity that may lead to interindividual variability in ketamine metabolism. We examined the N-demethylation of individual ketamine enantiomers using human liver microsomes (HLMs) genotyped for the CYP2B6*6 allele, insect cell-expressed recombinant CYP2B6 and CYP3A4 enzymes, and COS-1 cell-expressed recombinant CYP2B6.1 and CYP2B6.6 protein variant. Effects of CYP-selective inhibitors on norketamine formation were also determined in HLMs. The two-enzyme Michaelis-Menten model best fitted the HLM kinetic data. The Michaelis-Menten constants (K(m)) for the high-affinity enzyme and the low-affinity enzyme were similar to those for the expressed CYP2B6 and CYP3A4, respectively. The intrinsic clearance for both ketamine enantiomers by the high-affinity enzyme in HLMs with CYP2B6*1/*1 genotype were at least 2-fold and 6-fold higher, respectively, than those for CYP2B6*1/*6 genotype and CYP2B6*6/*6 genotype. The V(max) and K(m) values for CYP2B6.1 were approximately 160 and 70% of those for CYP2B6.6, respectively. N,N'N'-triethylenethiophosphoramide (thioTEPA) (CYP2B6 inhibitor, 25 μM) and the monoclonal antibody against CYP2B6 but not troleandomycin (CYP3A4 inhibitor, 25 μM) or the monoclonal antibody against CYP3A4 inhibited ketamine N-demethylation at clinically relevant concentrations. The degree of inhibition was significantly reduced in HLMs with the CYP2B6*6 allele (gene-dose P < 0.05). These results indicate a major role of CYP2B6 in ketamine N-demethylation in vitro and a significant impact of the CYP2B6*6 allele on enzyme-ketamine binding and catalytic activity.

  18. Epigenetic choreography of stem cells: the DNA demethylation episode of development.

    Science.gov (United States)

    Kar, Swayamsiddha; Parbin, Sabnam; Deb, Moonmoon; Shilpi, Arunima; Sengupta, Dipta; Rath, Sandip Kumar; Rakshit, Madhumita; Patra, Aditi; Patra, Samir Kumar

    2014-03-01

    Reversible DNA methylation is a fundamental epigenetic manipulator of the genomic information in eukaryotes. DNA demethylation plays a very significant role during embryonic development and stands out for its contribution in molecular reconfiguration during cellular differentiation for determining stem cell fate. DNA demethylation arbitrated extensive make-over of the genome via reprogramming in the early embryo results in stem cell plasticity followed by commitment to the principal cell lineages. This article attempts to highlight the sequential phases and hierarchical mode of DNA demethylation events during enactment of the molecular strategy for developmental transition. A comprehensive knowledge regarding the pattern of DNA demethylation during embryogenesis and organogenesis and study of the related lacunae will offer exciting avenues for future biomedical research and stem cell-based regenerative therapy.

  19. Putamen Activation Represents an Intrinsic Positive Prediction Error Signal for Visual Search in Repeated Configurations.

    Science.gov (United States)

    Sommer, Susanne; Pollmann, Stefan

    2016-01-01

    We investigated fMRI responses to visual search targets appearing at locations that were predicted by the search context. Based on previous work in visual category learning we expected an intrinsic reward prediction error signal in the putamen whenever the target appeared at a location that was predicted with some degree of uncertainty. Comparing target appearance at locations predicted with 50% probability to either locations predicted with 100% probability or unpredicted locations, increased activation was observed in left posterior putamen and adjacent left posterior insula. Thus, our hypothesis of an intrinsic prediction error-like signal was confirmed. This extends the observation of intrinsic prediction error-like signals, driven by intrinsic rather than extrinsic reward, to memory-driven visual search.

  20. Putamen Activation Represents an Intrinsic Positive Prediction Error Signal for Visual Search in Repeated Configurations

    Science.gov (United States)

    Sommer, Susanne; Pollmann, Stefan

    2016-01-01

    We investigated fMRI responses to visual search targets appearing at locations that were predicted by the search context. Based on previous work in visual category learning we expected an intrinsic reward prediction error signal in the putamen whenever the target appeared at a location that was predicted with some degree of uncertainty. Comparing target appearance at locations predicted with 50% probability to either locations predicted with 100% probability or unpredicted locations, increased activation was observed in left posterior putamen and adjacent left posterior insula. Thus, our hypothesis of an intrinsic prediction error-like signal was confirmed. This extends the observation of intrinsic prediction error-like signals, driven by intrinsic rather than extrinsic reward, to memory-driven visual search. PMID:27867436

  1. CpG demethylation in the neurotoxicity of 1-methyl-4-phenylpyridinium might mediate transcriptional up-regulation of α-synuclein in SH-SY5Y cells.

    Science.gov (United States)

    Yang, Jian; Yang, Zhaofei; Wang, Xuan; Sun, Min; Wang, Yong; Wang, Xiaomin

    2017-08-12

    The accumulation of α-synuclein is the primary pathological hallmark of Parkinson's disease (PD). In PD patients, CpG demethylation of intron-1 has been reported to be associated with α-synuclein up-regulation. Environmental factor, for example neurotoxin, is a major etiological risk factor in PD pathogenesis. However, the role of CpG methylation in neurotoxin-induced PD has not been addressed completely yet. To explore CpG methylation associating with α-synuclein transcription and its underlying mechanisms in the neurotoxin-induced PD pathology, human neuroblastoma SH-SY5Y cells were treated with neurotoxins 6-hydroxydopamine (6-OHDA) and 1-methyl-4-phenylpyridinium (MPP(+)). Results showed that MPP(+) induced demethylation of the whole length of the CpG island around SNCA promoter, and both 6-OHDA and MPP(+) resulted in up-regulation of SNCA transcription. The CpG demethylation around promoter resulted in up-regulation of SNCA transcriptional activity. In addition, 6-OHDA and MPP(+) induced the reduced levels of DNA methyltransferase (DNMT) 3a and DNMT3b but not DNMT1. These data suggested that CpG demethylation was induced by MPP(+) and might mediate up-regulation of SNCA transcription in neurotoxin-induced PD. And down-regulation of both DNMT3a and DNMT3b, but not DNMT1, might contribute to CpG demethylation of the SNCA promoter. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Cumene hydroperoxide-supported demethylation reactions catalyzed by cytochrome P450 2B4 lacking the NH2-terminal sequence.

    Science.gov (United States)

    Zhang, Y; Pernecky, S J

    1999-04-29

    Catalytic activities of cytochrome P450 2B4 lacking NH2-terminal amino acids 2-27 (wt Delta2B4) and that of truncated 2B4 containing a Pro to Ser mutation at position 221 were examined in a system supported by cumene hydroperoxide. Demethylation activities of either truncated 2B4 with N-methylaniline, N,N-dimethylaniline, and d-benzphetamine were lower than those of liver microsomal 2B4, whereas the rate of 1-phenylethanol oxidation to acetophenone catalyzed by liver microsomal and truncated 2B4 enzymes was nearly the same. The Km and Vmax values for cumene hydroperoxide in the demethylation of N-methylaniline by wt Delta2B4 were 20% and 28%, respectively, of those obtained for 2B4. The reaction with wt Delta2B4 displayed a lesser dependence on phospholipid than did that with 2B4, and a complex relationship between activity and substrate concentration. The results suggest that the NH2-terminal region contributes to interaction of oxidant, substrate, and phospholipid in cumene hydroperoxide-supported reactions catalyzed by cytochrome P450 2B4.

  3. Arsenic Demethylation by a C·As Lyase in Cyanobacterium Nostoc sp. PCC 7120.

    Science.gov (United States)

    Yan, Yu; Ye, Jun; Xue, Xi-Mei; Zhu, Yong-Guan

    2015-12-15

    Arsenic, a ubiquitous toxic substance, exists mainly as inorganic forms in the environment. It is perceived that organoarsenicals can be demethylated and degraded into inorganic arsenic by microorganisms. Few studies have focused on the mechanism of arsenic demethylation in bacteria. Here, we investigated arsenic demethylation in a typical freshwater cyanobacterium Nostoc sp. PCC 7120. This bacterium was able to demethylate monomethylarsenite [MAs(III)] rapidly to arsenite [As(III)] and also had the ability to demethylate monomethylarsenate [MAs(V)] to As(III). The NsarsI encoding a C·As lyase responsible for MAs(III) demethylation was cloned from Nostoc sp. PCC 7120 and heterologously expressed in an As-hypersensitive strain Escherichia coli AW3110 (ΔarsRBC). Expression of NsarsI was shown to confer MAs(III) resistance through arsenic demethylation. The purified NsArsI was further identified and functionally characterized in vitro. NsArsI existed mainly as the trimeric state, and the kinetic data were well-fit to the Hill equation with K0.5 = 7.55 ± 0.33 μM for MAs(III), Vmax = 0.79 ± 0.02 μM min(-1), and h = 2.7. Both of the NsArsI truncated derivatives lacking the C-terminal 10 residues (ArsI10) or 23 residues (ArsI23) had a reduced ability of MAs(III) demethylation. These results provide new insights for understanding the important role of cyanobacteria in arsenic biogeochemical cycling in the environment.

  4. Active Subduction on Both Coasts of Costa Rica Does not Represent an Important Tsunami Hazard

    Science.gov (United States)

    Protti, M.; Gonzalez, V.

    2007-05-01

    Costa Rica, on the southern terminus of the Middle American Trench is being affected by active subduction on both, along the Pacific coast as well as on its Caribbean coast. Three main subduction segments can be recognized along the Pacific coast: 1) under northwestern Costa Rica, off Papagayo Gulf and Nicoya peninsula, the Cocos plate is subducting under the Caribbean plate; 2) under southern Costa Rica (Osa and Burica peninsulas) the Cocos plate subducts under the Panama Block and 3) in the central Pacific coast (between Nicoya and Osa peninsulas) the Cocos plate subducts under a shear zone that marks the transition between the Caribbean and the Cocos plate. Along the Caribbean coast, south of Puerto Limon, the Caribbean plate subducts under the Panama block. Large subduction earthquakes occur under the Nicoya peninsula, Osa peninsula and south of Limon. Most of the rupture area of these large events lies below land so the deformation of the ocean floor is minimal and therefore the tsunamis they generate are small. No large subduction earthquakes occur under the central Pacific coast of Costa Rica due to the subduction of small sea mounts that act as small asperities without potential to accumulate large amounts of slip. For this reason the region between Nicoya and Osa peninsulas is not an important tsunamigenic zone.

  5. BOLD data representing activation and connectivity for rare no-go versus frequent go cues

    Directory of Open Access Journals (Sweden)

    Harma Meffert

    2016-06-01

    Full Text Available The neural circuitry underlying response control is often studied using go/no-go tasks, in which participants are required to respond as fast as possible to go cues and withhold from responding to no-go stimuli. In the current task, response control was studied using a fully counterbalanced design in which blocks with a low frequency of no-go cues (75% go, 25% no-go were alternated with blocks with a low frequency of go cues (25% go, 75% no-go; see also “Segregating attention from response control when performing a motor inhibition task: Segregating attention from response control” [1]. We applied a whole brain corrected, paired t-test to the data assessing for regions differentially activated by low frequency no-go cues relative to high frequency go cues. In addition, we conducted a generalized psychophysiological interaction analysis on the data using a right inferior frontal gyrus seed region. This region was identified through the BOLD response t-test and was chosen because right inferior gyrus is highly implicated in response inhibition.

  6. Genome-Wide Demethylation Promotes Triplet Repeat Instability Independently of Homologous Recombination

    Science.gov (United States)

    Dion, Vincent; Lin, Yunfu; Price, Brandee A.; Fyffe, Sharyl L.; Seluanov, Andrei; Gorbunova, Vera; Wilson, John H.

    2008-01-01

    Trinucleotide repeat instability is intrinsic to a family of human neurodegenerative diseases. The mechanism leading to repeat length variation is unclear. We previously showed that treatment with the demethylating agent 5-aza-2′-deoxycytidine (5-aza-CdR) dramatically increases triplet repeat instability in mammalian cells. Based on previous reports that demethylation increases homologous recombination (HR), and our own observations that HR destabilizes triplet repeats, we hypothesized that demethylation alters repeat stability by stimulating HR. Here, we test that hypothesis at the Aprt (adenosine phosphoribosyl transferase) locus in CHO cells, where CpG demethylation and HR have both been shown to increase CAG repeat instability. We find that the rate of HR at the Aprt locus is not altered by demethylation. The spectrum of recombinants, however, was shifted from the usual 6:1 ratio of conversions to crossovers to more equal proportions in 5-aza-CdR-treated cells. The subtle influences of demethylation on HR at the Aprt locus are not sufficient to account for its dramatic effects on repeat instability. We conclude that 5-aza-CdR promotes triplet repeat instability independently of HR. PMID:18083071

  7. Methylglyoxal induces endoplasmic reticulum stress and DNA demethylation in the Keap1 promoter of human lens epithelial cells and age-related cataracts.

    Science.gov (United States)

    Palsamy, Periyasamy; Bidasee, Keshore R; Ayaki, Masahiko; Augusteyn, Robert C; Chan, Jefferson Y; Shinohara, Toshimichi

    2014-07-01

    Age-related cataracts are a leading cause of blindness. Previously, we have demonstrated the association of the unfolded protein response with various cataractogenic stressors. However, DNA methylation alterations leading to suppression of lenticular antioxidant protection remains unclear. Here, we report the methylglyoxal-mediated sequential events responsible for Keap1 promoter DNA demethylation in human lens epithelial cells, because Keap1 is a negative regulatory protein that regulates the Nrf2 antioxidant protein. Methylglyoxal induces endoplasmic reticulum stress and activates the unfolded protein response leading to overproduction of reactive oxygen species before human lens epithelial cell death. Methylglyoxal also suppresses Nrf2 and DNA methyltransferases but activates the DNA demethylation pathway enzyme TET1. Bisulfite genomic DNA sequencing confirms the methylglyoxal-mediated Keap1 promoter DNA demethylation leading to overexpression of Keap1 mRNA and protein. Similarly, bisulfite genomic DNA sequencing shows that human clear lenses (n = 15) slowly lose 5-methylcytosine in the Keap1 promoter throughout life, at a rate of 1% per year. By contrast, diabetic cataractous lenses (n = 21) lose an average of 90% of the 5-methylcytosine regardless of age. Overexpressed Keap1 protein is responsible for decreasing Nrf2 by proteasomal degradation, thereby suppressing Nrf2-dependent stress protection. This study demonstrates for the first time the associations of unfolded protein response activation, Nrf2-dependent antioxidant system failure, and loss of Keap1 promoter methylation because of altered active and passive DNA demethylation pathway enzymes in human lens epithelial cells by methylglyoxal. As an outcome, the cellular redox balance is altered toward lens oxidation and cataract formation.

  8. Learning in later life: participation in formal, non-formal and informal activities in a nationally representative Spanish sample.

    Science.gov (United States)

    Villar, Feliciano; Celdrán, Montserrat

    2013-06-01

    This article examines the participation of Spanish older people in formal, non-formal and informal learning activities and presents a profile of participants in each kind of learning activity. We used data from a nationally representative sample of Spanish people between 60 and 75 years old (n = 4,703). The data were extracted from the 2007 Encuesta sobre la Participación de la Población Adulta en Actividades de Aprendizaje (EADA, Survey on Adult Population Involvement in Learning Activities). Overall, only 22.8 % of the sample participated in a learning activity. However, there was wide variation in the participation rates for the different types of activity. Informal activities were far more common than formal ones. Multivariate logistic regression indicated that education level and involvement in social and cultural activities were associated with likelihood of participating, regardless of the type of learning activity. When these variables were taken into account, age did not predict decreasing participation, at least in non-formal and informal activities. Implications for further research, future trends and policies to promote older adult education are discussed.

  9. Dioxin induces Ahr-dependent robust DNA demethylation of the Cyp1a1 promoter via Tdg in the mouse liver

    Science.gov (United States)

    Amenya, Hesbon Z.; Tohyama, Chiharu; Ohsako, Seiichiroh

    2016-10-01

    The aryl hydrocarbon receptor (Ahr) is a highly conserved nuclear receptor that plays an important role in the manifestation of toxicity induced by polycyclic aromatic hydrocarbons. As a xenobiotic sensor, Ahr is involved in chemical biotransformation through activation of drug metabolizing enzymes. The activated Ahr cooperates with coactivator complexes to induce epigenetic modifications at target genes. Thus, it is conceivable that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a potent Ahr ligand, may elicit robust epigenetic changes in vivo at the Ahr target gene cytochrome P450 1a1 (Cyp1a1). A single dose of TCDD administered to adult mice induced Ahr-dependent CpG hypomethylation, changes in histone modifications, and thymine DNA glycosylase (Tdg) recruitment at the Cyp1a1 promoter in the liver within 24 hrs. These epigenetic changes persisted until 40 days post-TCDD treatment and there was Cyp1a1 mRNA hyperinduction upon repeat administration of TCDD at this time-point. Our demethylation assay using siRNA knockdown and an in vitro methylated plasmid showed that Ahr, Tdg, and the ten-eleven translocation methyldioxygenases Tet2 and Tet3 are required for the TCDD-induced DNA demethylation. These results provide novel evidence of Ahr-driven active DNA demethylation and epigenetic memory. The epigenetic alterations influence response to subsequent chemical exposure and imply an adaptive mechanism to xenobiotic stress.

  10. Cornel Iridoid Glycoside Attenuates Tau Hyperphosphorylation by Inhibition of PP2A Demethylation.

    Science.gov (United States)

    Yang, Cui-Cui; Kuai, Xue-Xian; Li, Ya-Li; Zhang, Li; Yu, Jian-Chun; Li, Lin; Zhang, Lan

    2013-01-01

    Aim. The aim of the present study was to investigate the effect of cornel iridoid glycoside (CIG) on tau hyperphosphorylation induced by wortmannin (WT) and GF-109203X (GFX) and the underlying mechanisms. Methods. Human neuroblastoma SK-N-SH cells were preincubated with CIG (50, 100, and 200 µg/ml, resp.) for 24 h and then exposed to 10 µM WT and 10 µM GFX for 3 h after washing out CIG. Immunohistochemistry was used to observe the microtubular cytoskeleton of the cultured cells. Western blotting was used to measure the phosphorylation level of tau protein, glycogen synthase kinase 3 β (GSK-3 β ), and protein phosphatase 2A (PP2A). The activity of PP2A was detected by a biochemical assay. Results. Preincubation of CIG significantly attenuated the WT/GFX-induced tau hyperphosphorylation at the sites of Thr205, Thr212, Ser214, Thr217, Ser396, and PHF-1 and improved the damage of morphology and microtubular cytoskeleton of the cells. CIG did not prevent the decrease in p-AKT-ser473 and p-GSK-3 β -ser9 induced by WT/GFX. However, CIG significantly elevated the activity of PP2A by reducing the demethylation of PP2A catalytic subunit (PP2Ac) at Leu309 and the ratio of PME-1/LCMT in the WT/GFX-treated cells. The results suggest that CIG may be beneficial to the treatment of AD.

  11. Expression of Caveolin 1 is enhanced by DNA demethylation during adipocyte differentiation. status of insulin signaling.

    Science.gov (United States)

    Palacios-Ortega, Sara; Varela-Guruceaga, Maider; Milagro, Fermín Ignacio; Martínez, José Alfredo; de Miguel, Carlos

    2014-01-01

    Caveolin 1 (Cav-1) is an essential constituent of adipocyte caveolae which binds the beta subunit of the insulin receptor (IR) and is implicated in the regulation of insulin signaling. We have found that, during adipocyte differentiation of 3T3-L1 cells the promoter, exon 1 and first intron of the Cav-1 gene undergo a demethylation process that is accompanied by a strong induction of Cav-1 expression, indicating that epigenetic mechanisms must have a pivotal role in this differentiation process. Furthermore, IR, PKB-Akt and Glut-4 expression are also increased during the differentiation process suggesting a coordinated regulation with Cav-1. Activation of Cav-1 protein by phosphorylation arises during the differentiation process, yet in fully mature adipocytes insulin is no longer able to significantly increase Cav-1 phosphorylation. However, these long-term differentiated cells are still able to respond adequately to insulin, increasing IR and PKB-Akt phosphorylation and glucose uptake. The activation of Cav-1 during the adipocyte differentiation process could facilitate the maintenance of insulin sensitivity by these fully mature adipocytes isolated from additional external stimuli. However, under the influence of physiological conditions associated to obesity, such as chronic inflammation and hypoxia, insulin sensitivity would finally be compromised.

  12. Activity Profiles and Physiological Responses of Representative Tag Football Players in Relation to Playing Position and Physical Fitness

    Science.gov (United States)

    2015-01-01

    This study determined the physical fitness, match-activity profiles and physiological responses of representative tag football players and examined the relationship between physical fitness and the match-activity profile. Microtechnology devices and heart rate (HR) chest straps were used to determine the match-activity profiles of sixteen tag football players for five matches during the 2014 Australian National Championships. The relationships between lower body muscular power, straight line running speed and Yo-Yo intermittent recovery test level 2 (Yo-Yo IR2) and the match-activity profile were examined using Pearson’s correlation coefficients. Outside players had greater lower body muscular power (ES = 0.98) and straight line running speed (ES = 1.03–1.18) than inside players, and also covered greater very high-speed running (VHSR) distance/min (ES = 0.67) and reached higher peak running speeds (ES = 0.95) during matches. Inside and outside players performed a similar number of repeated high-intensity effort (RHIE) bouts and reported similar mean and maximum efforts per RHIE bout. However, there were differences between playing positions for mean and maximal RHIE effort durations (ES = 0.69–1.15) and mean RHIE bout recovery (ES = 0.56). Inside and outside players also reported small to moderate differences (ES = 0.43–0.80) for times spent in each HR zone. There were a number of moderate to very large correlations between physical fitness measures and match-activity profile variables. This study found lower body muscular power, straight line running speed and Yo-Yo IR2 to be related to the match-activities of representative tag football players, although differences between inside and outside players suggest that athlete testing and training practices should be modified for different playing positions. PMID:26642320

  13. Activity Profiles and Physiological Responses of Representative Tag Football Players in Relation to Playing Position and Physical Fitness.

    Directory of Open Access Journals (Sweden)

    Luke W Hogarth

    Full Text Available This study determined the physical fitness, match-activity profiles and physiological responses of representative tag football players and examined the relationship between physical fitness and the match-activity profile. Microtechnology devices and heart rate (HR chest straps were used to determine the match-activity profiles of sixteen tag football players for five matches during the 2014 Australian National Championships. The relationships between lower body muscular power, straight line running speed and Yo-Yo intermittent recovery test level 2 (Yo-Yo IR2 and the match-activity profile were examined using Pearson's correlation coefficients. Outside players had greater lower body muscular power (ES = 0.98 and straight line running speed (ES = 1.03-1.18 than inside players, and also covered greater very high-speed running (VHSR distance/min (ES = 0.67 and reached higher peak running speeds (ES = 0.95 during matches. Inside and outside players performed a similar number of repeated high-intensity effort (RHIE bouts and reported similar mean and maximum efforts per RHIE bout. However, there were differences between playing positions for mean and maximal RHIE effort durations (ES = 0.69-1.15 and mean RHIE bout recovery (ES = 0.56. Inside and outside players also reported small to moderate differences (ES = 0.43-0.80 for times spent in each HR zone. There were a number of moderate to very large correlations between physical fitness measures and match-activity profile variables. This study found lower body muscular power, straight line running speed and Yo-Yo IR2 to be related to the match-activities of representative tag football players, although differences between inside and outside players suggest that athlete testing and training practices should be modified for different playing positions.

  14. Harnessing Noxa demethylation to overcome Bortezomib resistance in mantle cell lymphoma.

    Science.gov (United States)

    Leshchenko, Violetta V; Kuo, Pei-Yu; Jiang, Zewei; Weniger, Marc A; Overbey, Jessica; Dunleavy, Kieron; Wilson, Wyndham H; Wiestner, Adrian; Parekh, Samir

    2015-09-29

    Bortezomib (BZM) is the first proteasome inhibitor approved for relapsed Mantle Cell Lymphoma (MCL) with durable responses seen in 30%-50% of patients. Given that a large proportion of patients will not respond, BZM resistance is a significant barrier to use this agent in MCL. We hypothesized that a subset of aberrantly methylated genes may be modulating BZM response in MCL patients. Genome-wide DNA methylation analysis using a NimbleGen array platform revealed a striking promoter hypomethylation in MCL patient samples following BZM treatment. Pathway analysis of differentially methylated genes identified molecular mechanisms of cancer as a top canonical pathway enriched among hypomethylated genes in BZM treated samples. Noxa, a pro-apoptotic Bcl-2 family member essential for the cytotoxicity of BZM, was significantly hypomethylated and induced following BZM treatment. Therapeutically, we could demethylate Noxa and induce anti-lymphoma activity using BZM and the DNA methytransferase inhibitor Decitabine (DAC) and their combination in vitro and in vivo in BZM resistant MCL cells. These findings suggest a role for dynamic Noxa methylation for the therapeutic benefit of BZM. Potent and synergistic cytotoxicity between BZM and DAC in vitro and in vivo supports a strategy for using epigenetic priming to overcome BZM resistance in relapsed MCL patients.

  15. Disulfiram Is a DNA Demethylating Agent and Inhibits Prostate Cancer Cell Growth

    Science.gov (United States)

    Lin, Jianqing; Haffner, Michael C.; Zhang, Yonggang; Lee, Byron H.; Brennen, W. Nathaniel; Britton, Justin; Kachhap, Sushant K.; Shim, Joong Sup; Liu, Jun O.; Nelson, William G.; Yegnasubramanian, Srinivasan; Carducci, Michael A.

    2011-01-01

    BACKGROUND The clinical success of the nucleoside analogs 5-aza-cytidine (5-azaC) and 5-aza-2′deoxycytidine (5-aza-dC) as DNA methyltransferase (DNMT) inhibitors has spurred interest in the development of non-nucleoside inhibitors with improved pharmacologic and safety profiles. Because DNMT catalysis features attack of cytosine bases by an enzyme thiol group, we tested whether disulfiram (DSF), a thiol-reactive compound with known clinical safety, demonstrated DNMT inhibitory activity. METHODS Inhibition of DNMT1 activity by DSF was assessed using methyltransferase activity assays with recombinant DNMT1. Next, prostate cancer cell lines were exposed to DSF and assessed for: i) reduction of global 5-methyl cytosine (5meC) content using liquid chromatography/tandem mass spectrometry (LC-MS/MS); ii) gene-specific promoter demethylation by methylation-specific PCR (MSP); and iii) gene-reactivation by real-time RT-PCR. DSF was also tested for growth inhibition using prostate cancer cell lines propagated in vitro in cell culture and in vivo as xenografts in nude mice. RESULTS Disulfiram showed a dose-dependent inhibition of DNMT1 activity on a hemimethylated DNA substrate. In prostate cancer cells in culture, DSF exposure led to reduction of global genomic 5meC content, increase in unmethylated APC and RARB gene promoters, and associated re-expression of these genes, but did not significantly alter prostate-specific antigen (PSA) expression. DSF significantly inhibited growth and clonogenic survival of prostate cancer cell lines in culture and showed a trend for reduced growth of prostate cancer xenografts. CONCLUSIONS Disulfiram is a non-nucleoside DNMT1 inhibitor that can reduce global 5meC content, reactivate epigenetically silenced genes, and significantly inhibit growth in prostate cancer cell lines. PMID:20809552

  16. Further investigations into the N-demethylation of oripavine using iron and stainless steel.

    Science.gov (United States)

    Kok, Gaik B; Scammells, Peter J

    2011-02-21

    Further investigations into the direct synthesis of N-nororipavine from oripavine using iron powder under non-classical Polonovski conditions have been conducted. The stoichiometry, solvents and iron oxidation rates were found to have a dramatic effect on the rate of N-demethylation as well as product yield. Herein, we also present high-yield access to the N-demethylated product simply by employing stainless steel rather than iron powder as redox catalyst. To our knowledge, this is the first time stainless steel has been used to moderate the redox chemistry of iron in organic synthesis.

  17. Promoted Interaction of C/EBPα with Demethylated Cxcr3 Gene Promoter Contributes to Neuropathic Pain in Mice.

    Science.gov (United States)

    Jiang, Bao-Chun; He, Li-Na; Wu, Xiao-Bo; Shi, Hui; Zhang, Wen-Wen; Zhang, Zhi-Jun; Cao, De-Li; Li, Chun-Hua; Gu, Jun; Gao, Yong-Jing

    2017-01-18

    DNA methylation has been implicated in the pathogenesis of chronic pain. However, the specific genes regulated by DNA methylation under neuropathic pain condition remain largely unknown. Here we investigated how chemokine receptor CXCR3 is regulated by DNA methylation and how it contributes to neuropathic pain induced by spinal nerve ligation (SNL) in mice. SNL increased Cxcr3 mRNA and protein expression in the neurons of the spinal cord. Meanwhile, the CpG (5'-cytosine-phosphate-guanine-3') island in the Cxcr3 gene promoter region was demethylated, and the expression of DNA methyltransferase 3b (DNMT3b) was decreased. SNL also increased the binding of CCAAT (cytidine-cytidine-adenosine-adenosine-thymidine)/enhancer binding protein α (C/EBPα) with Cxcr3 promoter and decreased the binding of DNMT3b with Cxcr3 promoter in the spinal cord. C/EBPα expression was increased in spinal neurons after SNL, and inhibition of C/EBPα by intrathecal small interfering RNA attenuated SNL-induced pain hypersensitivity and reduced Cxcr3 expression. Furthermore, SNL-induced mechanical allodynia and heat hyperalgesia were markedly reduced in Cxcr3(-/-) mice. Spinal inhibition of Cxcr3 by shRNA or CXCR3 antagonist also attenuated established neuropathic pain. Moreover, CXCL10, the ligand of CXCR3, was increased in spinal neurons and astrocytes after SNL. Superfusing spinal cord slices with CXCL10 enhanced spontaneous EPSCs and potentiated NMDA-induced and AMPA-induced currents of lamina II neurons. Finally, intrathecal injection of CXCL10 induced CXCR3-dependent pain hypersensitivity in naive mice. Collectively, our results demonstrated that CXCR3, increased by DNA demethylation and the enhanced interaction with C/EBPα, can be activated by CXCL10 to facilitate excitatory synaptic transmission and contribute to the maintenance of neuropathic pain. Peripheral nerve injury induces changes of gene expression in the spinal cord that may contribute to the pathogenesis of neuropathic

  18. Demethylating agent decitabine induces autologous cancer testis antigen specific cytotoxic T lymphocytes in vivo

    Institute of Scientific and Technical Information of China (English)

    ZHOU Ji-hao; YAO Yu-shi; WANG Li-xin; WANG Jia; LI Yong-hui; JIANG Meng-meng; ZHOU Min-hang

    2013-01-01

    Background Cancer testis antigens (CTAs) are a novel group of tumor associated antigens.Demethylating agent decitabine was reported to be able to up-regulate CTAs through its hypomethylation mechanism,thus enhance the immunogenicity of leukemia cells.However,few researches have ever focused on the questions that whether this immunostimulatory effect of decitabine could induce autologous CTA specific cytotoxic T lymphocytes (CTLs) in vivo,and if so,whether this effect contributes to disease control.In this study,we aimed to show that decitabine could induce specific autologous CTLs against some mouse CTAs in leukemia cells in vitro and in vivo.Methods Several mouse CTAs were screened by RT-PCR.CTL specific to one of the CTAs named P1A was detected and sorted by P1A specific dimer by flow cytometry.The activity of specific CTLs was measured by real time RT-PCR.Results We firstly screened expression of some CTAs in mouse leukemia cells before and after decitabine treatment and found that decitabine treatment did up-regulate expression of many CTAs.Then we measured the CTLs' activity specific to a mouse CTA P1A in vivo and showed that this activity increased after decitabine treatment.Finally,we sorted these in vivo induced P1A specific CTLs by flow cytometry and demonstrated their cytotoxicity against decitabine treated leukemia cells.Conclusions Our study showed the autologous immune response induced by decitabine in vivo.And more importantly,we firstly proved that this response may contribute to disease control.We believe that this immunostimulatory effect is another anti-cancer mechanism of decitabine,and this special effect would inspire new applications of decitabine in the field of leukemia treatment in the future.

  19. Representing dispositions

    Directory of Open Access Journals (Sweden)

    Röhl Johannes

    2011-08-01

    Full Text Available Abstract Dispositions and tendencies feature significantly in the biomedical domain and therefore in representations of knowledge of that domain. They are not only important for specific applications like an infectious disease ontology, but also as part of a general strategy for modelling knowledge about molecular interactions. But the task of representing dispositions in some formal ontological systems is fraught with several problems, which are partly due to the fact that Description Logics can only deal well with binary relations. The paper will discuss some of the results of the philosophical debate about dispositions, in order to see whether the formal relations needed to represent dispositions can be broken down to binary relations. Finally, we will discuss problems arising from the possibility of the absence of realizations, of multi-track or multi-trigger dispositions and offer suggestions on how to deal with them.

  20. Cornel Iridoid Glycoside Attenuates Tau Hyperphosphorylation by Inhibition of PP2A Demethylation

    Directory of Open Access Journals (Sweden)

    Cui-cui Yang

    2013-01-01

    Full Text Available Aim. The aim of the present study was to investigate the effect of cornel iridoid glycoside (CIG on tau hyperphosphorylation induced by wortmannin (WT and GF-109203X (GFX and the underlying mechanisms. Methods. Human neuroblastoma SK-N-SH cells were preincubated with CIG (50, 100, and 200 µg/ml, resp. for 24 h and then exposed to 10 µM WT and 10 µM GFX for 3 h after washing out CIG. Immunohistochemistry was used to observe the microtubular cytoskeleton of the cultured cells. Western blotting was used to measure the phosphorylation level of tau protein, glycogen synthase kinase 3β (GSK-3β, and protein phosphatase 2A (PP2A. The activity of PP2A was detected by a biochemical assay. Results. Preincubation of CIG significantly attenuated the WT/GFX-induced tau hyperphosphorylation at the sites of Thr205, Thr212, Ser214, Thr217, Ser396, and PHF-1 and improved the damage of morphology and microtubular cytoskeleton of the cells. CIG did not prevent the decrease in p-AKT-ser473 and p-GSK-3β-ser9 induced by WT/GFX. However, CIG significantly elevated the activity of PP2A by reducing the demethylation of PP2A catalytic subunit (PP2Ac at Leu309 and the ratio of PME-1/LCMT in the WT/GFX-treated cells. The results suggest that CIG may be beneficial to the treatment of AD.

  1. Base-oxidant promoted metal-free N-demethylation of arylamines

    Indian Academy of Sciences (India)

    VINAYAK BOTLA; CHIRANJEEVI BARREDDI; RAMANA V DAGGUPATI; CHANDRASEKHARAM MALAPAKA

    2016-09-01

    A metal-free oxidative N-demethylation of arylamines with triethylamine as a base and tert-butyl hydroperoxide (TBHP) as oxidant is reported in this paper. The reaction is general, practical, inexpensive, non-toxic, and the method followed is environmentally benign, with moderate to good yields.

  2. Raman spectroscopic characterisations and analytical discrimination between caffeine and demethylated analogues of pharmaceutical relevance

    Science.gov (United States)

    Edwards, H. G. M.; Munshi, T.; Anstis, M.

    2005-05-01

    The FT Raman spectrum of caffeine was analysed along with that of its demethylated analogues, theobromine and theophylline. The similar but not identical structures of these three compounds allowed a more detailed assignment of the Raman bands. Noticeable differences in the Raman spectra of these compounds were apparent and key marker bands have been identified for the spectroscopic identification of these three compounds.

  3. Testosterone Depletion Induces Demethylation of Murine Reelin Promoter CpG Dinucleotides: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Victor Augusto Moraes da Silva

    2015-01-01

    Full Text Available Schizophrenia (SZ is a debilitating mental disorder characterized by psychotic events, abnormal social behavior, false beliefs, and auditory hallucinations. Hypermethylation of the promoter region of reelin (RELN, a gene involved in regulation of neuronal positioning during telencephalic development, is strongly associated with low protein expression in several cortical structures and promoter hypermethylation in brain from postmortem SZ subjects. Recent experimental data suggests that testosterone is able to promote RELN demethylation, although no direct evidence of hormonal influence on reelin promoter methylation was obtained. We investigated if reduced levels of plasma testosterone in adult male mice lead to Reln promoter demethylation. Animals were administered with flutamide, an antiandrogenic compound, and reelin promoter methylation was assessed using methylationspecific PCR using bisulfite DNA from cerebellum. We found that flutamide was able to significantly lower plasma testosterone when compared to control mice, and treatment did not influence animal survival and body weight. We also show that low plasma testosterone was associated with demethylation of a cytosine residue located at −860 in reelin promoter region. These preliminary data suggest that androgenic hormones can influence cerebral reelin demethylation. To our knowledge, this is the first experimental approach directly linking testosterone depletion and RELN promoter methylation.

  4. Testosterone Depletion Induces Demethylation of Murine Reelin Promoter CpG Dinucleotides: A Preliminary Study.

    Science.gov (United States)

    da Silva, Victor Augusto Moraes; Dantas, Marília de Souza; Silva, Leonardo Agostinho de Castro; Carneiro, Juliana Garcia; Schamber-Reis, Bruno Luiz Fonseca

    2015-01-01

    Schizophrenia (SZ) is a debilitating mental disorder characterized by psychotic events, abnormal social behavior, false beliefs, and auditory hallucinations. Hypermethylation of the promoter region of reelin (RELN), a gene involved in regulation of neuronal positioning during telencephalic development, is strongly associated with low protein expression in several cortical structures and promoter hypermethylation in brain from postmortem SZ subjects. Recent experimental data suggests that testosterone is able to promote RELN demethylation, although no direct evidence of hormonal influence on reelin promoter methylation was obtained. We investigated if reduced levels of plasma testosterone in adult male mice lead to Reln promoter demethylation. Animals were administered with flutamide, an antiandrogenic compound, and reelin promoter methylation was assessed using methylationspecific PCR using bisulfite DNA from cerebellum. We found that flutamide was able to significantly lower plasma testosterone when compared to control mice, and treatment did not influence animal survival and body weight. We also show that low plasma testosterone was associated with demethylation of a cytosine residue located at -860 in reelin promoter region. These preliminary data suggest that androgenic hormones can influence cerebral reelin demethylation. To our knowledge, this is the first experimental approach directly linking testosterone depletion and RELN promoter methylation.

  5. Representing Development

    DEFF Research Database (Denmark)

    Representing Development presents the different social representations that have formed the idea of development in Western thinking over the past three centuries. Offering an acute perspective on the current state of developmental science and providing constructive insights into future pathways...... and development, addressing their contemporary enactments and reflecting on future theoretical and empirical directions. The first section of the book provides an historical account of early representations of development that, having come from life science, has shaped the way in which developmental science has...... approached development. Section two focuses upon the contemporary issues of developmental psychology, neuroscience and developmental science at large. The final section offers a series of commentaries pointing to the questions opened by the previous chapters, looking to outline the future lines...

  6. Tet3 and DNA replication mediate demethylation of both the maternal and paternal genomes in mouse zygotes.

    Science.gov (United States)

    Shen, Li; Inoue, Azusa; He, Jin; Liu, Yuting; Lu, Falong; Zhang, Yi

    2014-10-02

    With the exception of imprinted genes and certain repeats, DNA methylation is globally erased during preimplantation development. Recent studies have suggested that Tet3-mediated oxidation of 5-methylcytosine (5mC) and DNA replication-dependent dilution both contribute to global paternal DNA demethylation, but demethylation of the maternal genome occurs via replication. Here we present genome-scale DNA methylation maps for both the paternal and maternal genomes of Tet3-depleted and/or DNA replication-inhibited zygotes. In both genomes, we found that inhibition of DNA replication blocks DNA demethylation independently from Tet3 function and that Tet3 facilitates DNA demethylation largely by coupling with DNA replication. For both genomes, our data indicate that replication-dependent dilution is the major contributor to demethylation, but Tet3 plays an important role, particularly at certain loci. Our study thus defines the respective functions of Tet3 and DNA replication in paternal DNA demethylation and reveals an unexpected contribution of Tet3 to demethylation of the maternal genome.

  7. Association of Dietary Behaviors with Physical Activity in a Nationally Representative Sample of Children and Adolescents: the CASPIAN- IV Study

    Directory of Open Access Journals (Sweden)

    Saeid Safiri

    2016-03-01

    Full Text Available Background: Nutritional health and adequate physical activity (PA, especially in childhood and grow periods, have a substantial role in health. This study assessed the association of dietary behaviors (main courses and snacks intake with PA in children and adolescents. Materials and Methods: Using multistage random cluster sampling method, a representative sample of 14,880 school students were selected from urban and rural areas of 30 provinces of Iran. Through a validated questionnaire, daily consumption of main course ( breakfast, lunch, and dinner as well as daily consumption of different snacks and health foods ( fast foods, milk, vegetables, dry fruits, fresh fruits, sweetened beverages, salty snacks and sweets were recorded for every participants. Information of past week weekly frequency of leisure time PA was collected. Results: Overall, 13,486 out of 14,880 students (response rate: 90.6% participated in this survey. Participants consisted of 6,640 (49.2% girls and 75.6% urban residents; their mean and standard deviation (SD age was 12.47 (3.36 years. Daily consumption of fresh fruits (odds ratio [OR]: 1.35, 95%confidence interval [CI]: 1.20-1.52, dried fruits (OR: 1.21; 95%CI: 1.06-1.40, vegetable (OR: 1.39; 95% CI: 1.24-1.56, and milk (OR: 1.35; 95% CI: 1.21-1.52 increased the odds of high PA compare to low PA in adjusted model.  Skipping the breakfast, lunch and dinner decreased the odds of moderate and high PA compare to low PA (P

  8. Lipoxygenase—mediated N—demethylation of imipramine and related tricyclic antidepressants

    Institute of Scientific and Technical Information of China (English)

    HuJA; SajaM

    2002-01-01

    The ability of soybean lipoxygenase to mediate the N-demethylation of imipramine and related drugs in the presence of hydrogen peroxide was examined.Under optimal assay conditions,Vmax values of 14 to 18 mol formaldehyde·min-1·mol-1 enzyme were observed.An inhibition of formaldehyde and desipramine formation by nordihydroguaiaretic acid confirmed the lipoxygenase involvement.The blockade of the reaction by glutathione,dithiothreitol butylated hydroxyanisole (BHA) and butylated hydroxytoluene(BHT) indicated the generation of a free radical intermediate from imipramine.Desipramine,trimipramine,clomipramine,and diltiazem,but not amitriptyline and doxepin,were also oxidized,albeit at a lower rate.Collectively,the evidence gathered in this study suggests,for the first time,that tricyclic antidepressant drugs may undergo lipoxygenase-catalyzed N-demethylation.

  9. ALKBH4-dependent demethylation of actin regulates actomyosin dynamics

    DEFF Research Database (Denmark)

    Li, M.-M.; Shi, Y.; Niu, Y.

    2013-01-01

    and midbody via association with methylated actin. ALKBH4-mediated regulation of actomyosin dynamics is completely dependent on its catalytic activity. Disorganization of cleavage furrow components and multinucleation associated with ALKBH4 deficiency can all be restored by reconstitution with wild...

  10. Global identification of genes regulated by estrogen signaling and demethylation in MCF-7 breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Putnik, Milica, E-mail: milica.putnik@ki.se [Department of Biosciences and Nutrition, Novum, Karolinska Institutet, Huddinge S-14183 (Sweden); Zhao, Chunyan, E-mail: chunyan.zhao@ki.se [Department of Biosciences and Nutrition, Novum, Karolinska Institutet, Huddinge S-14183 (Sweden); Gustafsson, Jan-Ake, E-mail: jan-ake.gustafsson@ki.se [Department of Biosciences and Nutrition, Novum, Karolinska Institutet, Huddinge S-14183 (Sweden); Department of Biology and Biochemistry, Science and Engineering Research Center Bldg, University of Houston, Houston, TX 77204-5056 (United States); Dahlman-Wright, Karin, E-mail: karin.dahlman-wright@ki.se [Department of Biosciences and Nutrition, Novum, Karolinska Institutet, Huddinge S-14183 (Sweden)

    2012-09-14

    Highlights: Black-Right-Pointing-Pointer Estrogen signaling and demethylation can both control gene expression in breast cancers. Black-Right-Pointing-Pointer Cross-talk between these mechanisms is investigated in human MCF-7 breast cancer cells. Black-Right-Pointing-Pointer 137 genes are influenced by both 17{beta}-estradiol and demethylating agent 5-aza-2 Prime -deoxycytidine. Black-Right-Pointing-Pointer A set of genes is identified as targets of both estrogen signaling and demethylation. Black-Right-Pointing-Pointer There is no direct molecular interplay of mediators of estrogen and epigenetic signaling. -- Abstract: Estrogen signaling and epigenetic modifications, in particular DNA methylation, are involved in regulation of gene expression in breast cancers. Here we investigated a potential regulatory cross-talk between these two pathways by identifying their common target genes and exploring underlying molecular mechanisms in human MCF-7 breast cancer cells. Gene expression profiling revealed that the expression of approximately 140 genes was influenced by both 17{beta}-estradiol (E2) and a demethylating agent 5-aza-2 Prime -deoxycytidine (DAC). Gene ontology (GO) analysis suggests that these genes are involved in intracellular signaling cascades, regulation of cell proliferation and apoptosis. Based on previously reported association with breast cancer, estrogen signaling and/or DNA methylation, CpG island prediction and GO analysis, we selected six genes (BTG3, FHL2, PMAIP1, BTG2, CDKN1A and TGFB2) for further analysis. Tamoxifen reverses the effect of E2 on the expression of all selected genes, suggesting that they are direct targets of estrogen receptor. Furthermore, DAC treatment reactivates the expression of all selected genes in a dose-dependent manner. Promoter CpG island methylation status analysis revealed that only the promoters of BTG3 and FHL2 genes are methylated, with DAC inducing demethylation, suggesting DNA methylation directs repression of

  11. Prevalence and socio-demographic correlates of active commuting to school in a nationwide representative sample of German adolescents

    OpenAIRE

    Reimers, Anne Kerstin; Jekauc, Darko; Peterhans, Eliane; Wagner, Matthias O.; Woll, Alexander

    2013-01-01

    Objective. To assess the prevalence and socio-demographic correlates of walking and cycling to school in a nationwide representative cross-sectional sample of German adolescents.Methods. A sample of 1828 German adolescents aged 11–17 years were examined between 2003 and 2006. Mode of commuting to school was assessed using a reliable self-report measure. Socioeconomic status, migration background and residential area were assessed as socio-demographic variables using a parent-report questionna...

  12. Regeneration and DNA demethylation do not trigger PDX-1 expression in rat hepatocytes

    Institute of Scientific and Technical Information of China (English)

    Rudolf; T; Pillich; Gianfranco; Scarsella; Gianfranco; Risuleo

    2010-01-01

    AIM:To explore the possibility that PDX-1 gene is reactivated as a consequence of molecular events that occur during liver regeneration. METHODS:Rat hepatocytes were maintained in DMEM- F12,10%fetal bovine serum(FBS),penicillin/streptomycin and geneticin when applicable.Rat insulinoma RIN 1046-38 cells were maintained in M-199-10%FBS and penicillin/streptomycin.The final concentration of glucose was 11.1 mmol/L.During regeneration,lateral and medial liver lobes of adult male Wistar rats were surgically removed,with up 70%loss of liver mass.In methylation experiments,5-aza-deoxycytidine(5-aza-dC)was used.Primer3 software was used for poly- merase chain reaction(PCR).Quantitative real time PCR (qRT-PCR)was performed using SYBR Green technol- ogy;primers were designed by Beacon Designer 6 software.Western blotting and SDS-PAGE were performed according to standard procedures.Antibodies were purchased from commercial suppliers.RESULTS:We explored the possibility that liver regeneration could trigger PDX-1 expression,and hence insulin production.Twenty-four hours after surgical liver removal,regeneration was active as demonstrated by the increased proliferating cell nuclear antigen;however, all the other checked genes(involved in insulin gene expression):PC-1,Ngn3,NeuroD1,Btc,PDX-1 and Ins-1, were not related to the molecular events caused by this process.The only marker detected in regenerating liver was E47:a transcription factor of the the basic helixloop-helix family known to be expressed ubiquitously in mammalian cells.In the rat pancreas,almost all of the tested genes were expressed as shown by RT-PCR, except for Ngn3,which was silenced 2 d after birth. Therefore,the molecular events in liver regeneration are not sufficient to promote PDX-1 expression.DNA methylation is a known mechanism to achieve stable re- pression of gene expression in mammals:Hxk 2 gene is silenced through this mechanism in normal hepatocytes. The administration of 5-aza-dC to cultured cells

  13. Vimentin-Mediated Steroidogenesis Induced by Phthalate Esters: Involvement of DNA Demethylation and Nuclear Factor κB.

    Science.gov (United States)

    Li, Yuan; Hu, Yanhui; Dong, Congcong; Lu, Hongchao; Zhang, Chang; Hu, Qi; Li, Shifeng; Qin, Heng; Li, Zhong; Wang, Yubang

    2016-01-01

    Di-n-butyl phthalate (DBP) and its active metabolite, monobutyl phthalate (MBP) are the most common endocrine disrupting chemicals. Many studies indicate that high-doses of DBP and/or MBP exhibit toxicity on testicular function, however, little attention have been paid to the effects of low levels of DBP/MBP on steroidogenesis. As we all know, the steroidogenic acute regulatory protein (StAR) is a key regulator involved in the steroidogenesis. Here we found that, in addition to StAR, MBP/DBP increased the steroidogenesis by a cytoskeletal protein, vimentin. Briefly, in murine adrenocortical tumor (Y1) and the mouse Leydig tumor (MLTC-1) cells, vimentin regulated the secretion of progesterone. When these two cells were exposure to MBP, the DNA demethylation in the vimentin promoter was observed. In addition, MBP also induced the activation of nuclear factor kappa B (NF-κB, a transcriptional regulator of vimentin). These two processes improved the transcriptional elevation of vimentin. Knockdown of NF-κB/vimentin signaling blocked the DBP/MBP-induced steroidogenesis. These in vitro results were also confirmed via an in vivo model. By identifying a mechanism whereby DBP/MBP regulates vimentin, our results expand the understanding of the endocrine disrupting potential of phthalate esters.

  14. A 5-methylcytosine DNA glycosylase/lyase demethylates the retrotransposon Tos17 and promotes its transposition in rice

    KAUST Repository

    La, Honggui

    2011-09-06

    DNA 5-methylcytosine (5-meC) is an important epigenetic mark for transcriptional gene silencing in many eukaryotes. In Arabidopsis, 5-meC DNA glycosylase/lyases actively remove 5-meC to counter-act transcriptional gene silencing in a locus-specific manner, and have been suggested to maintain the expression of transposons. However, it is unclear whether plant DNA demethylases can promote the transposition of transposons. Here we report the functional characterization of the DNA glycosylase/lyase DNG701 in rice. DNG701 encodes a large (1,812 amino acid residues) DNA glycosylase domain protein. Recombinant DNG701 protein showed 5-meC DNA glycosylase and lyase activities in vitro. Knockout or knockdown of DNG701 in rice plants led to DNA hypermethylation and reduced expression of the retrotransposon Tos17. Tos17 showed less transposition in calli derived from dng701 knockout mutant seeds compared with that in wild-type calli. Overexpression of DNG701 in both rice calli and transgenic plants substantially reduced DNA methylation levels of Tos17 and enhanced its expression. The overexpression also led to more frequent transposition of Tos17 in calli. Our results demonstrate that rice DNG701 is a 5-meC DNA glycosylase/lyase responsible for the demethylation of Tos17 and this DNA demethylase plays a critical role in promoting Tos17 transposition in rice calli.

  15. Decaffeination and measurement of caffeine content by addicted Escherichia coli with a refactored N-demethylation operon from Pseudomonas putida CBB5.

    Science.gov (United States)

    Quandt, Erik M; Hammerling, Michael J; Summers, Ryan M; Otoupal, Peter B; Slater, Ben; Alnahhas, Razan N; Dasgupta, Aurko; Bachman, James L; Subramanian, Mani V; Barrick, Jeffrey E

    2013-06-21

    The widespread use of caffeine (1,3,7-trimethylxanthine) and other methylxanthines in beverages and pharmaceuticals has led to significant environmental pollution. We have developed a portable caffeine degradation operon by refactoring the alkylxanthine degradation (Alx) gene cluster from Pseudomonas putida CBB5 to function in Escherichia coli. In the process, we discovered that adding a glutathione S-transferase from Janthinobacterium sp. Marseille was necessary to achieve N 7 -demethylation activity. E. coli cells with the synthetic operon degrade caffeine to the guanine precursor, xanthine. Cells deficient in de novo guanine biosynthesis that contain the refactored operon are ″addicted″ to caffeine: their growth density is limited by the availability of caffeine or other xanthines. We show that the addicted strain can be used as a biosensor to measure the caffeine content of common beverages. The synthetic N-demethylation operon could be useful for reclaiming nutrient-rich byproducts of coffee bean processing and for the cost-effective bioproduction of methylxanthine drugs.

  16. Quaternary ammonium oxidative demethylation: X-ray crystallographic, resonance Raman, and UV-visible spectroscopic analysis of a Rieske-type demethylase.

    Science.gov (United States)

    Daughtry, Kelly D; Xiao, Youli; Stoner-Ma, Deborah; Cho, Eunsun; Orville, Allen M; Liu, Pinghua; Allen, Karen N

    2012-02-08

    Herein, the structure resulting from in situ turnover in a chemically challenging quaternary ammonium oxidative demethylation reaction was captured via crystallographic analysis and analyzed via single-crystal spectroscopy. Crystal structures were determined for the Rieske-type monooxygenase, stachydrine demethylase, in the unliganded state (at 1.6 Å resolution) and in the product complex (at 2.2 Å resolution). The ligand complex was obtained from enzyme aerobically cocrystallized with the substrate stachydrine (N,N-dimethylproline). The ligand electron density in the complex was interpreted as proline, generated within the active site at 100 K by the absorption of X-ray photon energy and two consecutive demethylation cycles. The oxidation state of the Rieske iron-sulfur cluster was characterized by UV-visible spectroscopy throughout X-ray data collection in conjunction with resonance Raman spectra collected before and after diffraction data. Shifts in the absorption band wavelength and intensity as a function of absorbed X-ray dose demonstrated that the Rieske center was reduced by solvated electrons generated by X-ray photons; the kinetics of the reduction process differed dramatically for the liganded complex compared to unliganded demethylase, which may correspond to the observed turnover in the crystal.

  17. Pharmacodynamic modelling of in vitro activity of tetracycline against a representative, naturally occurring population of porcine Escherichia coli

    DEFF Research Database (Denmark)

    Ahmad, Amais; Zachariasen, Camilla; Christiansen, Lasse Engbo;

    2015-01-01

    text] between susceptible and resistant strains in the absence of a drug was not different. EC 50 increased linearly with MIC on a log-log scale, and γ was different between susceptible and resistant strains. The in vitro model parameters described the inhibition effect of tetracycline on E. coli when...... of Escherichia coli representative of those found in the Danish pig population, we compared the growth of 50 randomly selected strains. The observed net growth rates were used to describe the in vitro pharmacodynamic relationship between drug concentration and net growth rate based on E max model with three...... parameters: maximum net growth rate (α max ); concentration for a half-maximal response (E max ); and the Hill coefficient (γ). The net growth rate in the absence of antibiotic did not differ between susceptible and resistant isolates (P = 0.97). The net growth rate decreased with increasing tetracycline...

  18. GC-MS-olfactometric characterization of the most aroma-active components in a representative aromatic extract from Iranian saffron (Crocus sativus L.).

    Science.gov (United States)

    Amanpour, Asghar; Sonmezdag, A Salih; Kelebek, Hasim; Selli, Serkan

    2015-09-01

    Aroma and aroma-active compounds of Iranian saffron (Crocus sativus L.) were analyzed by gas chromatography-mass spectrometry-olfactometry. The saffron aromatic extracts were obtained by four different extraction techniques including solvent-assisted flavour evaporation (SAFE), liquid-liquid extraction (LLE), solid phase extraction (SPE), and simultaneous distillation extraction (SDE) and compared to achieve a representative aromatic extract from saffron. According to sensory analysis, the aromatic extract obtained by SAFE was the most representative of saffron odour. A total of 28 aroma compounds were identified in saffron. Ketones were quantitatively the most dominant volatiles in saffron, followed by aldehydes and acids. Aroma extract dilution analysis (AEDA) was used for the determination of aroma-active compounds of saffron. A total of nine aroma-active compounds were detected in the aromatic extract. On the basis of the flavour dilution (FD) factor, the most powerful aroma active compounds were safranal (FD = 512), 4-ketoisophorone (FD = 256) and dihydrooxophorone (FD = 128).

  19. Active social participation and mortality risk among older people in Japan: results from a nationally representative sample.

    Science.gov (United States)

    Minagawa, Yuka; Saito, Yasuhiko

    2015-07-01

    A large literature suggests that active social participation contributes to the well-being of older people. Japan provides a compelling context to test this hypothesis due to its rapidly growing elderly population and the phenomenal health of the population. Using the Nihon University Japanese Longitudinal Study of Aging, this study examines how social participation, measured by group membership, is related to the risk of overall mortality among Japanese elders aged 65 and older. Results from Cox proportional hazards models show that group affiliation confers advantages against mortality risk, even after controlling for sociodemographic characteristics, physical health measures, and family relationship variables. In particular, activities geared more toward self-development, such as postretirement employment and lifelong learning, are strongly associated with lower levels of mortality. Findings suggest that continued social participation at advanced ages produces positive health consequences, highlighting the importance of active aging in achieving successful aging in the Japanese context.

  20. Geological activity of humans represented in the world heritage sites of India, Italy, and Russia: Evidence of the anthropocene

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    Ansari M K.

    2016-01-01

    Full Text Available The idea of the Anthropocene attracts attention of scientists, policy-makers, and broad public to the geological activity of humans and poses new important questions for the modern stratigraphy. The growth of the Anthropocene-related knowledge and its promotion can be based potentially on the UNESCO World Heritage Sites (WHS. On the one hand, many of these sites provide spectacular evidence of the human activity. On the other hand, these are remarkable tourist attractions. The WHSs of three heritage-rich countries, namely India, Italy, and Russia, have been assessed with regard to how these reflect the geological activity of humans. It is established that 65-90% of all WHSs in each country provide direct and indirect evidence of such an activity (artificial caves, terrace building, etc., which appears to be enough for the general discussion of the idea of the Anthropocene. However, the distribution of the WHSs by their age allows focusing only on the “early” (before 1800 AD start of the Anthropocene, which is not enough for full discussion of the lower limit of this unit. The examples considered in the present study imply that some WHSs alone provide very important pieces of the Anthropocene-related knowledge.

  1. Activity in neurons of a putative protocerebral circuit representing information about a ten component plant odour blend in Heliothis virescens.

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    Bjarte Bye Løfaldli

    2012-09-01

    Full Text Available The olfactory pathway in the insect brain is anatomically well described from the antennal lobe to the mushroom bodies and the lateral protocerebrum in several species. Less is known about the further connections of the olfactory network in protocerebrum and how information about relevant plant odorants and mixtures are represented in this network, resulting in output information mediated by descending neurons. In the present study we have recorded intracellularly followed by dye injections from neurons in the lateral- and superior protocerebrum of the moth, Heliothis virescens. As relevant stimuli, we have used selected primary plant odorants and mixtures of them. The results provide the morphology and physiological responses of neurons involved in a putative circuit connecting the mushroom body lobes, the superior and the lateral protocerebrum, as well as input to superior and lateral protocerebrum by one multiglomerular antennal lobe neuron and output from the lateral protocerebrum by one descending neuron. All neurons responded to one particular mixture of ten primary plant odorants, some of them also to single odorants of the mixture. Altogether, the physiological data indicate integration in protocerebral neurons of information from several of the receptor neuron types functionally described in this species.

  2. A phase I study of hydralazine to demethylate and reactivate the expression of tumor suppressor genes

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    Trejo-Becerril Catalina

    2005-04-01

    Full Text Available Abstract Background The antihypertensive compound hydralazine is a known demethylating agent. This phase I study evaluated the tolerability and its effects upon DNA methylation and gene reactivation in patients with untreated cervical cancer. Methods Hydralazine was administered to cohorts of 4 patients at the following dose levels: I 50 mg/day, II 75 mg/day, III 100 mg/day and IV 150 mg/day. Tumor biopsies and peripheral blood samples were taken the day before and after treatment. The genes APC, MGMT; ER, GSTP1, DAPK, RARβ, FHIT and p16 were evaluated pre and post-treatment for DNA promoter methylation and gene expression by MSP (Methylation-Specific PCR and RT-PCR respectively in each of the tumor samples. Methylation of the imprinted H19 gene and the "normally methylated" sequence clone 1.2 was also analyzed. Global DNA methylation was analyzed by capillary electrophoresis and cytosine extension assay. Toxicity was evaluated using the NCI Common Toxicity Criteria. Results Hydralazine was well tolerated. Toxicities were mild being the most common nausea, dizziness, fatigue, headache and palpitations. Overall, 70% of the pretreatment samples and all the patients had at least one methylated gene. Rates of demethylation at the different dose levels were as follows: 50 mg/day, 40%; 75 mg/day, 52%, 100 mg/day, 43%, and 150 mg/day, 32%. Gene expression analysis showed only 12 informative cases, of these 9 (75% re-expressed the gene. There was neither change in the methylation status of H19 and clone 1.2 nor changes in global DNA methylation. Conclusion Hydralazine at doses between 50 and 150 mg/day is well tolerated and effective to demethylate and reactivate the expression of tumor suppressor genes without affecting global DNA methylation

  3. N-demethylation and N-oxidation of imipramine in rat thoracic aortic endothelial cells.

    Science.gov (United States)

    Ueda, Yukari; Yaginuma, Toshihiko; Sakurai, Eiko; Sakurai, Eiichi

    2014-06-01

    The aim of this study was to examine whether cultured rat thoracic aortic endothelial cells (TAECs) have the ability to metabolize the tertiary amine, imipramine. In rat TAECs, imipramine was biotransformed into N-demethylate and N-oxide by cytochrome P450 (CYP) and flavin-containing monooxygenase (FMO), respectively. The intrinsic clearance (V max/K m) for the N-oxide formation was approximately five times as high as that for the N-demethylate formation, indicating that oxidation by CYP was much higher than that by FMO. Moreover, we suggest that CYP2C11 and CYP3A2 are key players in the metabolism to N-demethylate in rat TAECs using the respective anti-rat CYP antibodies (anti-CYP2C11 and anti-CYP3A2). The presence of CYP2C11 and CYP3A2 proteins was also confirmed in cultured rat TAECs using a polyclonal anti-CYP antibody and immunofluorescence microscopy. In contrast, the formation rate of N-oxide at pH 8.4 was higher than that at pH 7.4. Inhibition of N-oxide formation by methimazole was found to be the best model of competitive inhibition yielding an apparent K i value of 0.80 μmol/L, demonstrating that N-oxidation was catalyzed by FMO in rat TAECs. These results suggest that rat TAEC enzymes can convert substrates of exogenous origin such as imipramine, indicating that TAECs have an important function for metabolic products, besides hepatic cells.

  4. Evaluation of Antioxidant Activity, Polyphenolic Compounds, Amino Acids and Mineral Elements of Representative Genotypes of Lonicera edulis

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    Jiri Sochor

    2014-05-01

    Full Text Available The aim of this study was to evaluate the bioactive substances in 19 berry cultivars of edible honeysuckle (Lonicera edulis. A statistical evaluation was used to determine the relationship between the content of selected bioactive substances and individual cultivars. Regarding mineral elements, the content of sodium was measured using potentiometry and spectrophotometry. The content of selected polyphenolic compounds with high antioxidant activity was determined by a HPLC–UV/ED method. The total amount of polyphenols was determined by the Folin-Ciocalteu method. The antioxidant activity was determined using five methods (DPPH, FRAP, ABTS, FR and DMPD that differ in their principles. The content of 13 amino acids was determined by ion-exchange chromatography. The experimental results obtained for the different cultivars were evaluated and compared by statistical and bioinformatic methods. A unique feature of this study lies in the exhaustive analysis of the chosen parameters (amino acids, mineral elements, polyphenolic compounds and antioxidant activity during one growing season.

  5. Perceptions and Attitudes of Egyptian Health Professionals and Policy-Makers towards Pharmaceutical Sales Representatives and Other Promotional Activities.

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    Susan Kamal

    Full Text Available Pharmaceutical promotion activities in low and middle-income countries are often neither regulated nor monitored. While Egypt has the highest population and per capita use of medicines in the Arab world, we know very little about pharmaceutical companies promotional activities in the country.To explore and analyze the perceptions of physicians towards promotional and marketing activities of pharmaceutical companies among physicians and pharmacists in Egypt.Perspectives of different healthcare system stakeholders were explored through semi-structured, in-depth interviews conducted in 2014 in Cairo, Egypt. Interviewees were chosen via purposive sampling and snowball technique. Each interview was recorded and transcribed. Then qualitative, thematic analysis was conducted with the help of NVIVO software.The majority of physicians and pharmacists acknowledged exposure to pharmaceutical promotion. It was commonly believed that interaction with the pharmaceutical industry is necessary and both associated risks and benefits were acknowledged. The interviewed physicians considered themselves competent enough to minimize risks and maximize benefits to their prescribing habits. Views diverged on the extent and magnitude of the risks and benefits of pharmaceutical promotion, especially in regard to the influence on patients' health.Pharmaceutical promotion in Egypt is intensely directed at prescribers and dispensers. Physicians, pharmacists and policymakers expressed little skepticism to the influence of promotion towards their individual prescribing. Raising awareness of the pitfalls of pharmaceutical promotion is necessary, especially among the less experienced physicians.

  6. Perceptions and Attitudes of Egyptian Health Professionals and Policy-Makers towards Pharmaceutical Sales Representatives and Other Promotional Activities.

    Science.gov (United States)

    Kamal, Susan; Holmberg, Christine; Russell, Jean; Bochenek, Tomasz; Tobiasz-Adamczyk, Beata; Fischer, Christiane; Tinnemann, Peter

    2015-01-01

    Pharmaceutical promotion activities in low and middle-income countries are often neither regulated nor monitored. While Egypt has the highest population and per capita use of medicines in the Arab world, we know very little about pharmaceutical companies promotional activities in the country. To explore and analyze the perceptions of physicians towards promotional and marketing activities of pharmaceutical companies among physicians and pharmacists in Egypt. Perspectives of different healthcare system stakeholders were explored through semi-structured, in-depth interviews conducted in 2014 in Cairo, Egypt. Interviewees were chosen via purposive sampling and snowball technique. Each interview was recorded and transcribed. Then qualitative, thematic analysis was conducted with the help of NVIVO software. The majority of physicians and pharmacists acknowledged exposure to pharmaceutical promotion. It was commonly believed that interaction with the pharmaceutical industry is necessary and both associated risks and benefits were acknowledged. The interviewed physicians considered themselves competent enough to minimize risks and maximize benefits to their prescribing habits. Views diverged on the extent and magnitude of the risks and benefits of pharmaceutical promotion, especially in regard to the influence on patients' health. Pharmaceutical promotion in Egypt is intensely directed at prescribers and dispensers. Physicians, pharmacists and policymakers expressed little skepticism to the influence of promotion towards their individual prescribing. Raising awareness of the pitfalls of pharmaceutical promotion is necessary, especially among the less experienced physicians.

  7. Green synthesis of low-toxicity graphene-fulvic acid with an open band gap enhances demethylation of methylmercury.

    Science.gov (United States)

    Hu, Xiangang; Mu, Li; Lu, Kaicheng; Kang, Jia; Zhou, Qixing

    2014-06-25

    The demethylation of methylmercury has received substantial attention. Here, a novel chemical method for the demethylation of methylmercury is proposed. The low-toxicity graphene-fulvic acid (FA, a ubiquitous material in the environment) was synthesized without the use of a chemical reagent. The hybridized graphene-FA presented an indirect open band gap of 2.25-2.87 eV as well as adequate aqueous dispersion. More importantly, the hybridized graphene-FA exhibited 6- and 10-fold higher photocatalytic efficiencies for the demethylation of methylmercury than FA and free FA with graphene, respectively. This result implies that immobilized, rather than free, FA accelerated the catalysis. Furthermore, inorganic mercuric ion, elemental mercury, and mercuric oxide were identified as the primary demethylation products. For free FA with graphene, graphene quenches the excited-state FA, inhibiting the demethylation by electron transfer. In contrast, the graphene of the self-assembled graphene-FA serves as an electron reservoir, causing electron-hole pair separation. Graphene-FA showed a negligible toxicity toward microalgae compared to graphene. The above results reveal that the green synthesis of graphene and organic molecules is a convenient strategy for obtaining effective cocatalysts.

  8. ROS1 5-methylcytosine DNA glycosylase is a slow-turnover catalyst that initiates DNA demethylation in a distributive fashion.

    Science.gov (United States)

    Ponferrada-Marín, María Isabel; Roldán-Arjona, Teresa; Ariza, Rafael R

    2009-07-01

    Arabidopsis ROS1 belongs to a family of plant 5-methycytosine DNA glycosylases that initiate DNA demethylation through base excision. ROS1 displays the remarkable capacity to excise 5-meC, and to a lesser extent T, while retaining the ability to discriminate effectively against C and U. We found that replacement of the C5-methyl group by halogen substituents greatly decreased excision of the target base. Furthermore, 5-meC was excised more efficiently from mismatches, whereas excision of T only occurred when mispaired with G. These results suggest that ROS1 specificity arises by a combination of selective recognition at the active site and thermodynamic stability of the target base. We also found that ROS1 is a low-turnover catalyst because it binds tightly to the abasic site left after 5-meC removal. This binding leads to a highly distributive behaviour of the enzyme on DNA substrates containing multiple 5-meC residues, and may help to avoid generation of double-strand breaks during processing of bimethylated CG dinucleotides. We conclude that the biochemical properties of ROS1 are consistent with its proposed role in protecting the plant genome from excess methylation.

  9. Integrated epigenetics of human breast cancer: synoptic investigation of targeted genes, microRNAs and proteins upon demethylation treatment.

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    Ramin Radpour

    Full Text Available BACKGROUND: The contribution of aberrant DNA methylation in silencing of tumor suppressor genes (TSGs and microRNAs has been investigated. Since these epigenetic alterations are reversible, it became of interest to determine the effects of the 5-aza-2'-deoxycytidine (DAC demethylation therapy in breast cancer at different molecular levels. METHODS AND FINDINGS: Here we investigate a synoptic model to predict complete DAC treatment effects at the level of genes, microRNAs and proteins for several human breast cancer lines. The present study assessed an effective treatment dosage based on the cell viability, cytotoxicity, apoptosis and methylation assays for the investigated cell lines. A highly aggressive and a non-aggressive cell line were investigated using omics approaches such as MALDI-TOF MS, mRNA- and microRNA expression arrays, 2-D gel electrophoresis and LC-MS-MS. Complete molecular profiles including the biological interaction and possible early and late systematic stable or transient effects of the methylation inhibition were determined. Beside the activation of several epigenetically suppressed TSGs, we also showed significant dysregulation of some important oncogenes, oncomiRs and oncosuppressors miRNAs as well as drug tolerance genes/miRNAs/proteins. CONCLUSIONS: In the present study, the results denote some new molecular DAC targets and pathways based on the chemical modification of DNA methylation in breast cancer. The outlined approach might prove to be useful as an epigenetic treatment model also for other human solid tumors in the management of cancer patients.

  10. Inhibition of H3K4me2 Demethylation Protects Auditory Hair Cells from Neomycin-Induced Apoptosis.

    Science.gov (United States)

    He, Yingzi; Yu, Huiqian; Cai, Chengfu; Sun, Shan; Chai, Renjie; Li, Huawei

    2015-08-01

    Aminoglycoside-induced hair cell loss is a major cause of hearing impairment in children and deserves more attention in medical research. Epigenetic mechanisms have been shown to protect hair cells from ototoxic drugs. In this study, we focused on the role of dimethylated histone H3K4 (H3K4me2) in hair cell survival. To investigate the effects of lysine-specific demethylase 1 (LSD1)--the histone demethylase primarily responsible for demethylating H3K4me2--on neomycin-induced hair cell loss, isolated cochleae were pretreated with LSD1 inhibitors followed by neomycin exposure. There was a severe loss of hair cells in the organ of Corti after neomycin exposure, and inhibition of LSD1 significantly protected against neomycin-induced hair cell loss. H3K4me2 expression in the nuclei of hair cells decreased after exposure to neomycin, and blocking the decreased expression of H3K4me2 with LSD1 inhibitors prevented hair cell loss. Local delivery of these inhibitors in vivo also protected hair cells from neomycin-induced ototoxicity and maintained the hearing threshold in mice as determined by auditory brain stem response. This inhibition of neomycin-induced apoptosis occurs via reduced caspase-3 activation. Together, our findings demonstrate the protective role for H3K4me2 against neomycin-induced hair cell loss and hearing loss.

  11. Local chromatin microenvironment determines DNMT activity : from DNA methyltransferase to DNA demethylase or DNA dehydroxymethylase

    NARCIS (Netherlands)

    van der Wijst, Monique G. P.; Venkiteswaran, Muralidhar; Chen, Hui; Xu, Guo-Liang; Plosch, Torsten; Rots, Marianne G.

    2015-01-01

    Insights on active DNA demethylation disproved the original assumption that DNA methylation is a stable epigenetic modification. Interestingly, mammalian DNA methyltransferases 3A and 3B (DNMT-3A and -3B) have also been reported to induce active DNA demethylation, in addition to their well-known fun

  12. Photography by Cameras Integrated in Smartphones as a Tool for Analytical Chemistry Represented by an Butyrylcholinesterase Activity Assay.

    Science.gov (United States)

    Pohanka, Miroslav

    2015-06-11

    Smartphones are popular devices frequently equipped with sensitive sensors and great computational ability. Despite the widespread availability of smartphones, practical uses in analytical chemistry are limited, though some papers have proposed promising applications. In the present paper, a smartphone is used as a tool for the determination of cholinesterasemia i.e., the determination of a biochemical marker butyrylcholinesterase (BChE). The work should demonstrate suitability of a smartphone-integrated camera for analytical purposes. Paper strips soaked with indoxylacetate were used for the determination of BChE activity, while the standard Ellman's assay was used as a reference measurement. In the smartphone-based assay, BChE converted indoxylacetate to indigo blue and coloration was photographed using the phone's integrated camera. A RGB color model was analyzed and color values for the individual color channels were determined. The assay was verified using plasma samples and samples containing pure BChE, and validated using Ellmans's assay. The smartphone assay was proved to be reliable and applicable for routine diagnoses where BChE serves as a marker (liver function tests; some poisonings, etc.). It can be concluded that the assay is expected to be of practical applicability because of the results' relevance.

  13. Photography by Cameras Integrated in Smartphones as a Tool for Analytical Chemistry Represented by an Butyrylcholinesterase Activity Assay

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    Miroslav Pohanka

    2015-06-01

    Full Text Available Smartphones are popular devices frequently equipped with sensitive sensors and great computational ability. Despite the widespread availability of smartphones, practical uses in analytical chemistry are limited, though some papers have proposed promising applications. In the present paper, a smartphone is used as a tool for the determination of cholinesterasemia i.e., the determination of a biochemical marker butyrylcholinesterase (BChE. The work should demonstrate suitability of a smartphone-integrated camera for analytical purposes. Paper strips soaked with indoxylacetate were used for the determination of BChE activity, while the standard Ellman’s assay was used as a reference measurement. In the smartphone-based assay, BChE converted indoxylacetate to indigo blue and coloration was photographed using the phone’s integrated camera. A RGB color model was analyzed and color values for the individual color channels were determined. The assay was verified using plasma samples and samples containing pure BChE, and validated using Ellmans’s assay. The smartphone assay was proved to be reliable and applicable for routine diagnoses where BChE serves as a marker (liver function tests; some poisonings, etc.. It can be concluded that the assay is expected to be of practical applicability because of the results’ relevance.

  14. Detoxification of Deoxynivalenol via Glycosylation Represents Novel Insights on Antagonistic Activities of Trichoderma when Confronted with Fusarium graminearum

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    Ye Tian

    2016-11-01

    Full Text Available Deoxynivalenol (DON is a mycotoxin mainly produced by the Fusarium graminearum complex, which are important phytopathogens that can infect crops and lead to a serious disease called Fusarium head blight (FHB. As the most common B type trichothecene mycotoxin, DON has toxic effects on animals and humans, which poses a risk to food security. Thus, efforts have been devoted to control DON contamination in different ways. Management of DON production by Trichoderma strains as a biological control-based strategy has drawn great attention recently. In our study, eight selected Trichoderma strains were evaluated for their antagonistic activities on F. graminearum by dual culture on potato dextrose agar (PDA medium. As potential antagonists, Trichoderma strains showed prominent inhibitory effects on mycelial growth and mycotoxin production of F. graminearum. In addition, the modified mycotoxin deoxynivalenol-3-glucoside (D3G, which was once regarded as a detoxification product of DON in plant defense, was detected when Trichoderma were confronted with F. graminearum. The occurrence of D3G in F. graminearum and Trichoderma interaction was reported for the first time, and these findings provide evidence that Trichoderma strains possess a self-protection mechanism as plants to detoxify DON into D3G when competing with F. graminearum.

  15. Detoxification of Deoxynivalenol via Glycosylation Represents Novel Insights on Antagonistic Activities of Trichoderma when Confronted with Fusarium graminearum

    Science.gov (United States)

    Tian, Ye; Tan, Yanglan; Liu, Na; Yan, Zheng; Liao, Yucai; Chen, Jie; de Saeger, Sarah; Yang, Hua; Zhang, Qiaoyan; Wu, Aibo

    2016-01-01

    Deoxynivalenol (DON) is a mycotoxin mainly produced by the Fusarium graminearum complex, which are important phytopathogens that can infect crops and lead to a serious disease called Fusarium head blight (FHB). As the most common B type trichothecene mycotoxin, DON has toxic effects on animals and humans, which poses a risk to food security. Thus, efforts have been devoted to control DON contamination in different ways. Management of DON production by Trichoderma strains as a biological control-based strategy has drawn great attention recently. In our study, eight selected Trichoderma strains were evaluated for their antagonistic activities on F. graminearum by dual culture on potato dextrose agar (PDA) medium. As potential antagonists, Trichoderma strains showed prominent inhibitory effects on mycelial growth and mycotoxin production of F. graminearum. In addition, the modified mycotoxin deoxynivalenol-3-glucoside (D3G), which was once regarded as a detoxification product of DON in plant defense, was detected when Trichoderma were confronted with F. graminearum. The occurrence of D3G in F. graminearum and Trichoderma interaction was reported for the first time, and these findings provide evidence that Trichoderma strains possess a self-protection mechanism as plants to detoxify DON into D3G when competing with F. graminearum. PMID:27854265

  16. Cumene hydroperoxide supported demethylation of N,N-dimethylaniline by cytochrome P-450 from adrenal cortex mitochondria.

    Science.gov (United States)

    Akhrem, A A; Khatyleva SYu; Shkumatov, V M; Chashchin, V L; Kiselev, P A

    1982-01-01

    The interaction of highly purified cytochrome P-450 from bovine adrenal cortex mitochondria (cytochrome P-450scc) with N,N-dimethylaniline (DMA), aniline, N-dimethylcyclohexylamine and cumene hydroperoxide (CHP) has been investigated. The formation of complexes between cytochrome P-450scc and the above listed compounds could be demonstrated. The reaction of oxidative demethylation of DMA by cumene hydroperoxide involving cytochrome P-450scc has been carried out at 37 degrees C; the mechanism of this process is discussed. Incubation of cytochrome P-450scc with negatively charged phospholipids, phosphatidylglycerol (PG), and phosphatidylinosite (PI) exerts an inhibiting effect on the reaction of oxidative demethylation. The interaction of cytochrome P-450scc with CHP is accompanied by hemoprotein destruction in a complex biphasic way. The process of oxidative demethylation of DMA in the system of cytochrome P-450scc-CHP has been concluded to have a predominantly radical character.

  17. Representing Microbial Dormancy in Soil Decomposition Models Improves Model Performance and Reveals Key Ecosystem Controls on Microbial Activity

    Science.gov (United States)

    He, Y.; Yang, J.; Zhuang, Q.; Wang, G.; Liu, Y.

    2014-12-01

    Climate feedbacks from soils can result from environmental change and subsequent responses of plant and microbial communities and nutrient cycling. Explicit consideration of microbial life history traits and strategy may be necessary to predict climate feedbacks due to microbial physiology and community changes and their associated effect on carbon cycling. In this study, we developed an explicit microbial-enzyme decomposition model and examined model performance with and without representation of dormancy at six temperate forest sites with observed soil efflux ranged from 4 to 10 years across different forest types. We then extrapolated the model to all temperate forests in the Northern Hemisphere (25-50°N) to investigate spatial controls on microbial and soil C dynamics. Both models captured the observed soil heterotrophic respiration (RH), yet no-dormancy model consistently exhibited large seasonal amplitude and overestimation in microbial biomass. Spatially, the total RH from temperate forests based on dormancy model amounts to 6.88PgC/yr, and 7.99PgC/yr based on no-dormancy model. However, no-dormancy model notably overestimated the ratio of microbial biomass to SOC. Spatial correlation analysis revealed key controls of soil C:N ratio on the active proportion of microbial biomass, whereas local dormancy is primarily controlled by soil moisture and temperature, indicating scale-dependent environmental and biotic controls on microbial and SOC dynamics. These developments should provide essential support to modeling future soil carbon dynamics and enhance the avenue for collaboration between empirical soil experiment and modeling in the sense that more microbial physiological measurements are needed to better constrain and evaluate the models.

  18. Clomipramine demethylation rate is important on the outcome of obsessive-compulsive disorder treatment.

    Science.gov (United States)

    Marcourakis, Tania; Bernik, Márcio A; Lotufo Neto, Francisco; Gedanke Shavitt, Roseli; Gorenstein, Clarice

    2015-01-01

    The aim of this study was to investigate the influence of demethylation rate on the outcome of obsessive-compulsive disorder patients treated with clomipramine. Eighteen patients meeting the DSM-IV criteria for obsessive-compulsive disorder received 150-300 mg of clomipramine daily in a single-blind design for 12 weeks. The patients were evaluated with the Clinical Global Impression scale and the Yale-Brown Obsessive-Compulsive Scale (YBOCS). Clinical assessment and serum measurements of clomipramine and desmethylclomipramine were carried out at baseline and after 3, 6, 8, 10, and 12 weeks. A greater improvement in Clinical Global Impression scale rating was associated with a lower desmethylclomipramine/daily dose and the total clomipramine and desmethylclomipramine/daily dose. Moreover, an improved response on the YBOCS-obsession score was associated with higher serum levels of clomipramine and the total clomipramine and desmethylclomipramine/daily dose. Patients with a greater reduction in baseline YBOCS rating had a lower desmethylclomipramine/clomipramine ratio. These data suggest that a lower demethylation rate correlates with better clinical outcome.

  19. Ascorbic acid increases demethylation in somatic cell nuclear transfer embryos of the pig (

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    Minghui Zhao

    2017-07-01

    Full Text Available Objective Investigated the effect and mechanism of ascorbic acid on the development of porcine embryos produced by somatic cell nuclear transfer (SCNT. Methods Porcine embryos were produced by SCNT and cultured in the presence or absence of ascorbic acid. Ten-eleven translocation 3 (TET3 in oocytes was knocked down by siRNA injection. After ascorbic acid treatment, reprogramming genes were analyzed by realtime reverse transcription-polymerase chain reaction (RT-PCR. Furthermore, relative 5-methylcytosine and 5-hydroxymethylcytosine content in pronucleus were detected by realtime PCR. Results Ascorbic acid significantly increased the development of porcine embryos produced by SCNT. After SCNT, transcript levels of reprogramming genes, Pou5f1, Sox2, and Klf were significantly increased in blastocysts. Furthermore, ascorbic acid reduced 5-methylcytosine content in pronuclear embryos compared with the control group. Knock down of TET3 in porcine oocytes significantly prevents the demethylation of somatic cell nucleus after SCNT, even if in the presence of ascorbic acid. Conclusion Ascorbic acid enhanced the development of porcine SCNT embryos via the increased TET3 mediated demethylation of somatic nucleus.

  20. Continuous Zebularine Treatment Effectively Sustains Demethylation in Human Bladder Cancer Cells

    Science.gov (United States)

    Cheng, Jonathan C.; Weisenberger, Daniel J.; Gonzales, Felicidad A.; Liang, Gangning; Xu, Guo-Liang; Hu, Ye-Guang; Marquez, Victor E.; Jones, Peter A.

    2004-01-01

    During tumorigenesis, tumor suppressor and cancer-related genes are commonly silenced by aberrant DNA methylation in their promoter regions. Recently, we reported that zebularine [1-(β-d-ribofuranosyl)-1,2-dihydropyrimidin-2-one] acts as an inhibitor of DNA methylation and exhibits chemical stability and minimal cytotoxicity both in vitro and in vivo. Here we show that continuous application of zebularine to T24 cells induces and maintains p16 gene expression and sustains demethylation of the 5′ region for over 40 days, preventing remethylation. In addition, continuous zebularine treatment effectively and globally demethylated various hypermethylated regions, especially CpG-poor regions. The drug caused a complete depletion of extractable DNA methyltransferase 1 (DNMT1) and partial depletion of DNMT3a and DNMT3b3. Last, sequential treatment with 5-aza-2′-deoxycytidine followed by zebularine hindered the remethylation of the p16 5′ region and gene resilencing, suggesting the possible combination use of both drugs as a potential anticancer regimen. PMID:14729971

  1. DNA demethylation upregulated Nrf2 expression in Alzheimer's disease cellular model

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    Huimin eCao

    2016-01-01

    Full Text Available Nuclear factor erythroid 2-related factor 2 (Nrf2 is an important transcription factor in the defense against oxidative stress. Cumulative evidence has shown that oxidative stress plays a key role in the pathogenesis of Alzheimer's disease (AD. Previous animal and clinical studies had observed decreased expression of Nrf2 in AD. However, the underlying regulation mechanisms of Nrf2 in AD remain unclear. Here, we used the DNA methyltransferases (Dnmts inhibitor 5-aza-2′-deoxycytidine (5-Aza to test whether Nrf2 expression was regulated by methylation in N2a cells characterizing by expressing human Swedish mutant amyloid precursor protein (N2a/APPswe. We found 5-Aza treatment increased Nrf2 at both mRNA and protein levels via down-regulating the expression of Dnmts and DNA demethylation. In addition, 5-Aza mediated upregulation of Nrf2 expression was concomitant with increased nuclear translocation of Nrf2 and higher expression of Nrf2 downstream target gene NAD(PH:quinone oxidoreductas (NQO1. Our study showed that DNA demethylation promoted the Nrf2 cell signaling pathway, which may enhance the antioxidant system against AD development.

  2. DNMT3B gene amplification predicts resistance to DNA demethylating drugs.

    Science.gov (United States)

    Simó-Riudalbas, Laia; Melo, Sónia A; Esteller, Manel

    2011-07-01

    Disruption of the DNA methylation landscape is one of the most common features of human tumors. However, genetic alterations of DNA methyltransferases (DNMTs) have not been described in carcinogenesis. Herein, we show that pancreatic and breast cancer cells undergo gene amplification of the DNA methyltransferase 3B (DNMT3B). The presence of extra copies of the DNMT3B gene is linked to higher levels of the corresponding mRNA and protein. Most importantly, the elevated gene dosage of DNMT3B is associated with increased resistance to the growth-inhibitory effect mediated by DNA demethylating agents. In particular, cancer cells harboring DNMT3B gene amplification are less sensitive to the decrease in cell viability caused by 5-azacytidine (Vidaza), 5-aza-2-deoxycytidine (Decitabine), and SGI-1027. Overall, the data confirm DNMT3B as a bona fide oncogene in human cancer and support the incorporation of the DNMT3B copy number assay into current clinical trials assessing the efficacy of DNA demethylating drugs in solid tumors.

  3. Quantitative measurement of demethylation of /sup 14/C-methoxyl labeled DMPEA and TMA-2 in rats

    Energy Technology Data Exchange (ETDEWEB)

    Sargent, T. III; Shulgin, A.T.; Kusubov, N.

    1976-01-01

    Some reports have suggested that methylation and demethylation of compounds related to 6-hydroxydopamine may be involved in endogenous mental disorder. We report the synthesis of 3,4-dimethyoxyphenethylamine (DMPEA) and 2,4,5-trimethoxyphenylisopropylamine (TMA-2) with each methoxyl group separately labeled with /sup 14/C. The rate and percent demethylation of these two compounds, with five labeled positions, were determined in the rat. The results suggest that TMA-2 might be metabolized to a hydroquinone in vivo; a similar metabolic intermediate of the psychoactive compound DOM is known to give rise in vitro to an indole.

  4. 5-azacytidine improves the osteogenic differentiation potential of aged human adipose-derived mesenchymal stem cells by DNA demethylation.

    Directory of Open Access Journals (Sweden)

    Xueying Yan

    Full Text Available The therapeutic value of adipose-derived mesenchymal stem cells (Ad-MSCs for bone regeneration is critically discussed. A possible reason for reduced osteogenic potential may be an age-related deterioration of the Ad-MSCs. In long term in vitro culture, epigenomic changes in DNA methylation are known to cause gene silencing, affecting stem cell growth as well as the differentiation potential. In this study, we observed an age-related decline in proliferation of primary human Ad-MSCs. Decreased Nanog, Oct4 and Lin28A and increased Sox2 gene-expression was accompanied by an impaired osteogenic differentiation potential of Ad-MSCs isolated from old donors (>60 a as compared to Ad-MSCs isolated from younger donors (<45 a. 5-hydroxymethylcytosine (5 hmC and 5-methylcytonsine (5 mC distribution as well as TET gene expression were evaluated to assess the evidence of active DNA demethylation. We observed a decrease of 5 hmC in Ad-MSCs from older donors. Incubation of these cells with 5-Azacytidine induced proliferation and improved the osteogenic differentiation potential in these cells. The increase in AP activity and matrix mineralization was associated with an increased presence of 5 hmC as well as with an increased TET2 and TET3 gene expression. Our data show, for the first time, a decrease of DNA hydroxymethylation in Ad-MSCs which correlates with donor-age and that treatment with 5-Azacytidine provides an approach which could be used to rejuvenate Ad-MSCs from aged donors.

  5. Dissecting the sterol C-4 demethylation process in higher plants. From structures and genes to catalytic mechanism.

    Science.gov (United States)

    Rahier, Alain

    2011-03-01

    Sterols become functional only after removal of the two methyl groups at C-4. This review focuses on the sterol C-4 demethylation process in higher plants. An intriguing aspect in the removal of the two C-4 methyl groups of sterol precursors in plants is that it does not occur consecutively as it does in yeast and animals, but is interrupted by several enzymatic steps. Each C-4 demethylation step involves the sequential participation of three individual enzymatic reactions including a sterol methyl oxidase (SMO), a 3β-hydroxysteroid-dehydrogenase/C4-decarboxylase (3βHSD/D) and a 3-ketosteroid reductase (SR). The distant location of the two C-4 demethylations in the sterol pathway requires distinct SMOs with respective substrate specificity. Combination of genetic and molecular enzymological approaches allowed a thorough identification and functional characterization of two distinct families of SMOs genes and two 3βHSD/D genes. For the latter, these studies provided the first molecularly and functionally characterized HSDs from a short chain dehydrogenase/reductase family in plants, and the first data on 3-D molecular interactions of an enzyme of the postoxidosqualene cyclase sterol biosynthetic pathway with its substrate in animals, yeast and higher plants. Characterization of these three new components involved in C-4 demethylation participates to the completion of the molecular inventory of sterol synthesis in higher plants.

  6. Sensitivity of Mycosphaerella graminicola isolates to demethylation-inhibiting (DMI) fungicides

    DEFF Research Database (Denmark)

    Ronis, Antanas; Jørgensen, Lise Nistrup; Semaskiene, Roma

    2014-01-01

    Mycosphaerella graminicola (Fuckel) J. Schröt. (anamorph Zymoseptoria tritici (Desm.) Quaedvlieg & Crous) causes Septoria leaf blotch disease of wheat. The disease can be responsible for yield losses of 30–50% and, when severe, requires management with a fungicide. Single picnidia isolates...... collected from different locations of Lithuania were tested in vitro for sensitivity to demethylation-inhibiting (DMI) fungicides epoxiconazole, cyproconazole and prothioconazole. Fungicide concentrations were chosen from the proposed Fungicide Resistance Action Committee (FRAC) methods. Microtitre plates...... that fungicides epoxiconazole and prothioconazole significantly reduced the area under the disease progress curve (AUDPC) values of Septoria leaf blotch compared with untreated plots in winter wheat. In most cases, a single fungicide application significantly increased grain yield and a thousand grain weight...

  7. Human concentrative nucleoside transporter 1-mediated uptake of 5-azacytidine enhances DNA demethylation.

    Science.gov (United States)

    Rius, Maria; Stresemann, Carlo; Keller, Daniela; Brom, Manuela; Schirrmacher, Esther; Keppler, Dietrich; Lyko, Frank

    2009-01-01

    The DNA methyltransferase inhibitors 5-azacytidine (5-azaCyd) and 5-aza-2'-deoxycytidine have found increasing use for the treatment of myeloid leukemias and solid tumors. Both nucleoside analogues must be transported into cells and phosphorylated before they can be incorporated into DNA and inactivate DNA methyltransferases. The members of the human equilibrative and concentrative nucleoside transporter families mediate transport of natural nucleosides and some nucleoside analogues into cells. However, the molecular identity of the transport proteins responsible for mediating the uptake of 5-azanucleosides has remained unknown. To this end, we have generated a stably transfected Madin-Darby canine kidney strain II cell line expressing recombinant hCNT1. An antiserum directed against hCNT1 specifically detected the protein in the apical membrane of hCNT1-expressing Madin-Darby canine kidney cells. Using [14C]5-azaCyd, we show here that hCNT1 mediated the Na+-dependent uptake of this drug with a Km value of 63 micromol/L. Na+-dependent transport of radiolabeled cytidine, uridine, and 5-fluoro-5'-deoxyuridine further showed the functionality of the transporter. hCNT1-expressing cells were significantly more sensitive to 5-azaCyd, and drug-dependent covalent trapping of DNA methyltransferase 1 was substantially more pronounced. Importantly, these results correlated with a significant sensitization of hCNT1-expressing cells toward the demethylating effects of 5-azaCyd and 5-aza-2'-deoxycytidine. In conclusion, our study identifies 5-azaCyd as a novel substrate for hCNT1 and provides direct evidence that hCNT1 is involved in the DNA-demethylating effects of this drug.

  8. The applicability of activities in kinetic expressions: A more fundamental approach to represent the kinetics of the system CO2–OH-salt in terms of activities

    NARCIS (Netherlands)

    Haubrock, J.; Hogendoorn, J.A.; Versteeg, G.F.

    2007-01-01

    The applicability of utilizing activities instead of concentrations in kinetic expressions has been investigated using the reaction of CO2 in sodium hydroxide solutions also containing different neutral salts (LiCl, KCl and NaCl) as model system. For hydroxide systems it is known that when the react

  9. Demethylation and alterations in the expression level of the cell cycle-related genes as possible mechanisms in arsenic trioxide-induced cell cycle arrest in human breast cancer cells.

    Science.gov (United States)

    Moghaddaskho, Farima; Eyvani, Haniyeh; Ghadami, Mohsen; Tavakkoly-Bazzaz, Javad; Alimoghaddam, Kamran; Ghavamzadeh, Ardeshir; Ghaffari, Seyed H

    2017-02-01

    Arsenic trioxide (As2O3) has been used clinically as an anti-tumor agent. Its mechanisms are mostly considered to be the induction of apoptosis and cell cycle arrest. However, the detailed molecular mechanisms of its anti-cancer action through cell cycle arrest are poorly known. Furthermore, As2O3 has been shown to be a potential DNA methylation inhibitor, inducing DNA hypomethylation. We hypothesize that As2O3 may affect the expression of cell cycle regulatory genes by interfering with DNA methylation patterns. To explore this, we examined promoter methylation status of 24 cell cycle genes in breast cancer cell lines and in a normal breast tissue sample by methylation-specific polymerase chain reaction and/or restriction enzyme-based methods. Gene expression level and cell cycle distribution were quantified by real-time polymerase chain reaction and flow cytometric analyses, respectively. Our methylation analysis indicates that only promoters of RBL1 (p107), RASSF1A, and cyclin D2 were aberrantly methylated in studied breast cancer cell lines. As2O3 induced CpG island demethylation in promoter regions of these genes and restores their expression correlated with DNA methyltransferase inhibition. As2O3 also induced alterations in messenger RNA expression of several cell cycle-related genes independent of demethylation. Flow cytometric analysis revealed that the cell cycle arrest induced by As2O3 varied depending on cell lines, MCF-7 at G1 phase and both MDA-MB-231 and MDA-MB-468 cells at G2/M phase. These changes at transcriptional level of the cell cycle genes by the molecular mechanisms dependent and independent of demethylation are likely to represent the mechanisms of cell cycle redistribution in breast cancer cells, in response to As2O3 treatment.

  10. Hyperimmune antisera against synthetic peptides representing the glycoprotein of human immunodeficiency virus type 2 can mediate neutralization and antibody-dependent cytotoxic activity.

    Science.gov (United States)

    Björling, E; Broliden, K; Bernardi, D; Utter, G; Thorstensson, R; Chiodi, F; Norrby, E

    1991-01-01

    Twenty-five 13- to 35-amino-acid-long peptides representing regions of human immunodeficiency virus type 2 (HIV-2), strain SBL6669, envelope proteins were evaluated for their immunogenic activity in guinea pigs. The peptides were selected to provide homologous representation of sites in the HIV-1 envelope proteins that were previously documented to have a particular immunogenic importance. A number of the HIV-2 peptides were found to be capable of inducing strain SBL6669 neutralizing and antibody-dependent cellular cytotoxicity (ADCC) antibodies. Two overlapping peptides covering amino acids 311-337 representing the central and C-terminal part of the variable third (V3) region, terminology according to Modrow et al. [Modrow, S., Hahn, B., Shaw, G. M., Gallo, R. C., Wong-Staal, F. & Wolf, H. (1987) J. Virol. 61, 570-578], showed the most pronounced capacity to induce neutralizing antibodies. One of the peptides (amino acids 318-337) also induced antibodies mediating ADCC. Two additional regions in the large glycoprotein, gp125, containing linear sites reacting with neutralizing antibodies were identified (amino acids, 119-137 and 472-509). The transmembrane protein, gp36, of HIV-2 harbored two regions of importance for induction of neutralizing antibodies (amino acids 595-614 and 714-729). ADCC activity was induced by two additional gp125-specific peptides (amino acids 291-311 and 446-461). Thus, except for the single V3-specific site there was no correlation between linear immunogenic sites stimulating neutralizing antibody and ADCC activity. These findings pave the way for development of synthetic vaccines against HIV-2 and possibly also simian immunodeficiency virus infections. The capacity of such a product to induce protective immunity can be evaluated in macaque monkeys. Images PMID:2068087

  11. Active play and screen time in US children aged 4 to 11 years in relation to sociodemographic and weight status characteristics: a nationally representative cross-sectional analysis

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    Must Aviva

    2008-10-01

    Full Text Available Abstract Background The high prevalence of childhood obesity underscores the importance of monitoring population trends in children's activity and screen time, and describing associations with child age, gender, race/ethnicity, and weight status. Our objective was to estimate the proportion of young children in the US who have low levels of active play or high levels of screen time, or who have both these behaviors, and to describe associations with age, gender, race/ethnicity, and weight status. Methods We analyzed data collected during the National Health and Nutrition Examination Surveys 2001–2004, a US nationally representative cross-sectional study. We studied 2964 children aged 4.00 to 11.99 years. Our main outcomes were reported weekly times that the child played or exercised hard enough to sweat or breathe hard (active play, daily hours the child watched television/videos, used computers, or played computer games (screen time, and the combination of low active play and high screen time. Low active play was defined as active play 6 times or less per week. High screen time was defined as more than 2 hours per day. We accounted for the complex survey design in analyses and report proportions and 95% confidence intervals. We used Wald Chi-square to test for differences between proportions. To identify factors associated with low active play and high screen time, we used multivariate logistic regression. Results Of US children aged 4 to 11 years, 37.3% (95% confidence interval, 34.1% to 40.4% had low levels of active play, 65.0% (95% CI, 61.4% to 68.5% had high screen time, and 26.3% (95% CI, 23.8% to 28.9% had both these behaviors. Characteristics associated with a higher probability of simultaneously having low active play and high screen time were older age, female gender, non-Hispanic black race/ethnicity, and having a BMI-for-age ≥95th percentile of the CDC growth reference. Conclusion Many young children in the US are reported to

  12. A NEW MODEL AND IMPROVED CABLE FUNCTION FOR REPRESENTING THE ACTIVATING PERIPHERAL NERVES BY A TRANSVERSE ELECTRIC FIELD DURING MAGNETIC STIMULATION

    Institute of Scientific and Technical Information of China (English)

    Yu Hui; Zheng Chongxun; Wang Haiyan; Wang Yi

    2005-01-01

    Objective Previous studies of peripheral nerves activation during magnetic stimulation have focused almost exclusively on the cause of high external parallel electric field along the nerves, whereas the effect of the transverse component has been ignored. In the present paper, the classical cable function is modified to represent the excitation of peripheral nerves stimulated by a transverse electric field during magnetic stimulation. Methods Responses of the Ranvier nodes to a transverse-field are thoroughly investigated by mathematic simulation. Results The simulation demonstrates that the excitation results from the net inward current driven by an external field. Based on a two-stage process, a novel model is introduced to describe peripheral nerves stimulated by a transverse-field. Based on the new model, the classical cable function is modified. Conclusion Using this modified cable equation, the excitation threshold of peripheral nerves in a transverse field during MS is obtained. The modified cable equation can be used to represent the response of peripheral nerves by an arbitrary electric field.

  13. Motivation and planning as mediators of the relation between social support and physical activity among U.S. adolescents: a nationally representative study

    Science.gov (United States)

    2014-01-01

    Background More than half of U.S. high-school students do not meet the moderate and vigorous physical activity (MVPA) 5 hours per week recommendation. The purpose of this study was to determine how individual dimensions (motivation and planning) mediate the relationship of social context with physical activity by integrating available measures of personal characteristic including internal/external motivations (derived from Self-Determination Theory -SDT]) for MVPA, MVPA planning, peer MVPA, and parental support to better understand adolescent MVPA. Methods Survey responses of a nationally representative cohort of 11th graders (N = 2439) in the NEXT Generation Health Study were analyzed with structural equation modeling. Results Adolescent MVPA was directly, significantly associated with MVPA planning (β = 0.17), peer MVPA (β = 0.21), and internal motivation (β = 0.50). Internal motivation was associated with peer MVPA (β = 0.31), parental support for MVPA (β = 0.16), and external motivation (β = 0.40). A significant relation between parental support and external motivation (β = 0.31) was also found. Conclusions Adolescents with higher internal motivation and more active friends were more likely to engage in MVPA. The results are consistent with SDT and suggest that planning is an important construct for adolescent MVPA. PMID:24656181

  14. Mescaline-induced changes of brain-cortex ribosomes. Mescaline demethylase activity of brain-cortex soluble supernatant.

    Science.gov (United States)

    Datta, R K; Ghosh, J J

    1977-02-01

    Brain-cortex slices demethylate mescaline and p-methoxyacetanilide, a reference O-demethylating substrate, though the rate of demethylation of mescaline is about one third that of the reference substrate. The demethylase activity is localized mostly in the soluble supernatant (105 000 x g). It is purified 47-fold with respect to the demethylation of mescaline by ammonium sulfate precipitation and DEAE cellulose chromatography. The partially purified demethylase, which is stable for 3-5 days at -5 degrees C in the presence of dithiothreitol and glutathione and is inhibited by p-chloromercuribenzoate, has maximal activity at pH between 7.2 and 8.0. It demethylates mescaline into 3,4-dimethoxy-5-hydroxyphenethylamine and 3,5-dimethoxy-4-hydroxyphenethylamine and some unidentified derivatives.

  15. Perceived and Objective Measures of Neighborhood Walkability and Physical Activity among Adults in Japan: A Multilevel Analysis of a Nationally Representative Sample.

    Science.gov (United States)

    Hanibuchi, Tomoya; Nakaya, Tomoki; Yonejima, Mayuko; Honjo, Kaori

    2015-10-23

    Although associations between a person's neighborhood and their health have been studied internationally, most studies have been limited to a few cities or towns. Therefore, we used a nationally representative sample to explore whether perceived and objective neighborhood walkability was associated with the physical activity of residents. Data were analyzed from the Japanese General Social Surveys of 2010 (n = 2395; 1114 men and 1281 women). Perceived walkability was scored using factor analysis for the respondents' perceptions of neighborhood conditions, while objective walkability was measured using the geographic information system approach. Finally, multilevel logistic regression analysis was performed to examine whether neighborhood walkability was associated with the frequency of leisure-time physical activity (LTPA) among respondents. We found that perceived walkability was positively associated with the frequency of LTPA (odds ratio of the highest quartile was 1.53 (1.14-2.05) compared with the lowest quartile); however, objective walkability showed no association. When stratified by gender, an association between perceived walkability and LTPA was observed among women, but only a marginally significant association was present between objective walkability and LTPA among men. We conclude that the association between neighborhood walkability and LTPA can be partially generalized across Japan.

  16. PM6 study of free radical scavenging mechanisms of flavonoids: why does O-H bond dissociation enthalpy effectively represent free radical scavenging activity?

    Science.gov (United States)

    Amić, Dragan; Stepanić, Višnja; Lučić, Bono; Marković, Zoran; Dimitrić Marković, Jasmina M

    2013-06-01

    It is well known that the bond dissociation enthalpy (BDE) of the O-H group is related to the hydrogen atom transfer (HAT) mechanism of free radical scavenging that is preferred in gas-phase and non-polar solvents. The present work shows that the BDE may also be related to radical scavenging processes taking place in polar solvents, i.e., single electron transfer followed by proton transfer (SET-PT) and sequential proton loss electron transfer (SPLET). This is so because the total energy requirements related to the SET-PT [sum of the ionization potential (IP) and proton dissociation enthalpy (PDE)] and the SPLET [sum of the proton affinity (PA) and electron transfer enthalpy (ETE)] are perfectly correlated with the BDE. This could explain why the published data for polyphenolic antioxidant activity measured by various assays are better correlated with the BDE than with other reaction enthalpies involved in radical scavenging mechanisms, i.e., the IP, PDE, PA and ETE. The BDE is fairly well able to rank flavonoids as antioxidants in any medium, but to conclude which radical scavenging mechanism represents the most probable reaction pathway from the thermodynamic point of view, the IP and PA (ETE) should also be considered. This is exemplified in the case of the radical scavenging activity of 25 flavonoids.

  17. O-Demethylation and successive oxidative dechlorination of methoxychlor by Bradyrhizobium sp. strain 17-4, isolated from river sediment.

    Science.gov (United States)

    Satsuma, Koji; Masuda, Minoru; Sato, Kiyoshi

    2012-08-01

    O-Demethylation of insecticide methoxychlor is well known as a phase I metabolic reaction in various eukaryotic organisms. Regarding prokaryotic organisms, however, no individual species involved in such reaction have been specified and characterized so far. Here we successfully isolated a bacterium that mediates oxidative transformation of methoxychlor, including O-demethylation and dechlorination, from river sediment. The isolate was found to be closely related to Bradyrhizobium elkanii at the 16S rRNA gene sequence level (100% identical). However, based on some differences in the physiological properties of this bacterium, we determined that it was actually a different species, Bradyrhizobium sp. strain 17-4. The isolate mediated O-demethylation of methoxychlor to yield a monophenolic derivative [Mono-OH; 1,1,1-trichloro-2-(4-hydroxyphenyl)-2-(4-methoxyphenyl)ethane] as the primary degradation product. The chiral high-performance liquid chromatography (HPLC) analysis revealed that the isolate possesses high enantioselectivity favoring the formation of (S)-Mono-OH (nearly 100%). Accompanied by the sequential O-demethylation to form the bis-phenolic derivative Bis-OH [1,1,1-trichloro-2,2-bis(4-hydroxyphenyl)ethane], oxidative dechlorination of the side chain proceeded, and monophenolic carboxylic acid accumulated, followed by the formation of multiple unidentified polar degradation products. The breakdown proceeded more rapidly when reductively dechlorinated (dichloro-form) methoxychlor was applied as the initial substrate. The resultant carboxylic acids and polar degradation products are likely further biodegraded by ubiquitous bacteria. The isolate possibly plays an important role for complete degradation (mineralization) of methoxychlor by providing the readily biodegradable substrates.

  18. Evaluation of mercury methylation and methylmercury demethylation rates in vegetated and non-vegetated saltmarsh sediments from two Portuguese estuaries.

    Science.gov (United States)

    Cesário, Rute; Hintelmann, Holger; Mendes, Ricardo; Eckey, Kevin; Dimock, Brian; Araújo, Beatriz; Mota, Ana Maria; Canário, João

    2017-07-01

    Neurotoxic methylmercury (MMHg) is formed from inorganic divalent mercury (Hg(2+)). However, it is poorly understood to what extent different mercury (Hg) pools contribute to existent MMHg levels. In this study, ambient concentrations of total Hg (THg) and MMHg as well as rates of methylation and demethylation were measured simultaneously in sediments with and without salt-marsh plant vegetation, which were collected in Guadiana and Tagus estuaries, Portugal. Concurrent processes of Hg methylation and MMHg demethylation were directly monitored and compared by spiking sediments cores with stable isotope tracers of (199)Hg(2+) and CH3(201)Hg(+) followed by gas chromatographic separation and isotope-specific detection using inductively coupled plasma mass spectrometry. Compared to the Guadiana estuary, where concentrations were comparatively low, THg and MMHg levels varied between vegetated and non-vegetated sediments collected at the Rosário site (ROS) of the Tagus estuary. Methylation (KM) and demethylation rates (KD) were also different between estuaries being dependent on the presence of vegetation. In addition, the type of macrophyte species influenced KM and KD values. In fact, the highest KM value was found in Sarcocornia fruticosa vegetated sediments at the Castro Marim site in Guadiana (CM, 0.160 day(-1)) and the lowest KM was observed in non-vegetated sediments at the Alcochete site in Tagus (ALC, 0.009 day(-1)). KD varied by a factor of three among sites with highest rates of demethylation observed in non-vegetated sediments in Guadiana (12 ± 1.3 day(-1), corresponding to a half-life of 1.4 ± 0.2 h). This study clearly shows that the presence of vegetation in sediments favors the formation of MMHg. Moreover, this effect might be site specific and further studies are needed to confirm the findings reported here. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Demethylation of FANCF gene may be a potential treatment through inhibiting the proliferation of cervical cancer

    Institute of Scientific and Technical Information of China (English)

    Min Li; Chanyu Zhang

    2013-01-01

    Objective: The aim of the study was to explore the effect of demethylating agent 5-Aza-2'-deoxycytidine (5-ADC) on expression of Fanconi anemia complementation group F (FANCF) gene and the proliferation of cervical cancer cells, to observe cell's sensitivity to chemotherapeutic drug taxol, and to explore the antitumor effect of 5-ADC as well as the new treatment of cervical cancer. Methods: Cervical cancer cell lines SiHa (FANCF gene full-methylated) and Hela (unmethylated) were treated with 5-ADC. We used the methylation-specific PCR (MSP), reverse transcription-polymerase chain reaction (RT-PCR) and Western blot to detect the FANCF methylation, mRNA and protein respectively. The 3-(4,5-dimethylthiazol-2- yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to detect the proliferation of cells. The cytotoxicity of taxol was measured by flow cytometer. The nude mice bearing SiHa was used to observe the effect of 5-ADC in vivo. Results: Inhibition of DNA promoter methylation by 5-ADC reactivated the expression of FANCF mRNA and protein in SiHa cells, consistent with decreased growth speed and increased taxol resistance. These results were proven in experiments in vivo. Conclusion: The 5-ADC probably become a potential treatment drug through inhibiting the proliferation of cervical cancer cells in taxol-resistant patients.

  20. The putative oncogene GASC1 demethylates tri- and dimethylated lysine 9 on histone H3

    DEFF Research Database (Denmark)

    Cloos, Paul A C; Christensen, Jesper; Agger, Karl;

    2006-01-01

    Methylation of lysine and arginine residues on histone tails affects chromatin structure and gene transcription. Tri- and dimethylation of lysine 9 on histone H3 (H3K9me3/me2) is required for the binding of the repressive protein HP1 and is associated with heterochromatin formation...... and transcriptional repression in a variety of species. H3K9me3 has long been regarded as a 'permanent' epigenetic mark. In a search for proteins and complexes interacting with H3K9me3, we identified the protein GASC1 (gene amplified in squamous cell carcinoma 1), which belongs to the JMJD2 (jumonji domain containing...... 2) subfamily of the jumonji family, and is also known as JMJD2C. Here we show that three members of this subfamily of proteins demethylate H3K9me3/me2 in vitro through a hydroxylation reaction requiring iron and alpha-ketoglutarate as cofactors. Furthermore, we demonstrate that ectopic expression...

  1. Antiproliferative effects of DNA methyltransferase 3B depletion are not associated with DNA demethylation.

    Directory of Open Access Journals (Sweden)

    Sabine Hagemann

    Full Text Available Silencing of genes by hypermethylation contributes to cancer progression and has been shown to occur with increased frequency at specific genomic loci. However, the precise mechanisms underlying the establishment and maintenance of aberrant methylation marks are still elusive. The de novo DNA methyltransferase 3B (DNMT3B has been suggested to play an important role in the generation of cancer-specific methylation patterns. Previous studies have shown that a reduction of DNMT3B protein levels induces antiproliferative effects in cancer cells that were attributed to the demethylation and reactivation of tumor suppressor genes. However, methylation changes have not been analyzed in detail yet. Using RNA interference we reduced DNMT3B protein levels in colon cancer cell lines. Our results confirm that depletion of DNMT3B specifically reduced the proliferation rate of DNMT3B-overexpressing colon cancer cell lines. However, genome-scale DNA methylation profiling failed to reveal methylation changes at putative DNMT3B target genes, even in the complete absence of DNMT3B. These results show that DNMT3B is dispensable for the maintenance of aberrant DNA methylation patterns in human colon cancer cells and they have important implications for the development of targeted DNA methyltransferase inhibitors as epigenetic cancer drugs.

  2. Suppression of TET1-Dependent DNA Demethylation Is Essential for KRAS-Mediated Transformation

    Directory of Open Access Journals (Sweden)

    Bo-Kuan Wu

    2014-12-01

    Full Text Available Hypermethylation-mediated tumor suppressor gene (TSG silencing is a central epigenetic alteration in RAS-dependent tumorigenesis. Ten-eleven translocation (TET enzymes can depress DNA methylation by hydroxylation of 5-methylcytosine (5mC bases to 5-hydroxymethylcytosine (5hmC. Here, we report that suppression of TET1 is required for KRAS-induced DNA hypermethylation and cellular transformation. In distinct nonmalignant cell lines, oncogenic KRAS promotes transformation by inhibiting TET1 expression via the ERK-signaling pathway. This reduces chromatin occupancy of TET1 at TSG promoters, lowers levels of 5hmC, and increases levels of 5mC and 5mC-dependent transcriptional silencing. Restoration of TET1 expression by ERK pathway inhibition or ectopic TET1 reintroduction in KRAS-transformed cells reactivates TSGs and inhibits colony formation. KRAS knockdown increases TET1 expression and diminishes colony-forming ability, whereas KRAS/TET1 double knockdown bypasses the KRAS dependence of KRAS-addicted cancer cells. Thus, suppression of TET1-dependent DNA demethylation is critical for KRAS-mediated transformation.

  3. The interaction between alpha 7 nicotinic acetylcholine receptor and nuclear peroxisome proliferator-activated receptor-α represents a new antinociceptive signaling pathway in mice.

    Science.gov (United States)

    Donvito, Giulia; Bagdas, Deniz; Toma, Wisam; Rahimpour, Elnaz; Jackson, Asti; Meade, Julie A; AlSharari, Shakir; Kulkarni, Abhijit R; Ivy Carroll, F; Lichtman, Aron H; Papke, Roger L; Thakur, Ganesh A; Imad Damaj, M

    2017-09-01

    Recently, α7 nicotinic acetylcholine receptors (nAChRs), primarily activated by binding of orthosteric agonists, represent a target for anti-inflammatory and analgesic drug development. These receptors may also be modulated by positive allosteric modulators (PAMs), ago-allosteric ligands (ago-PAMs), and α7-silent agonists. Activation of α7 nAChRs has been reported to increase the brain levels of endogenous ligands for nuclear peroxisome proliferator-activated receptors type-α (PPAR-α), palmitoylethanolamide (PEA) and oleoylethanolamide (OEA), in a Ca(2+)-dependent manner. Here, we investigated potential crosstalk between α7 nAChR and PPAR-α, using the formalin test, a mouse model of tonic pain. Using pharmacological and genetic approaches, we found that PNU282987, a full α7 agonist, attenuated formalin-induced nociceptive behavior in α7-dependent manner. Interestingly, the selective PPAR-α antagonist GW6471 blocked the antinociceptive effects of PNU282987, but did not alter the antinociceptive responses evoked by the α7 nAChR PAM PNU120596, ago-PAM GAT107, and silent agonist NS6740. Moreover, GW6471 administered systemically or spinally, but not via the intraplantar surface of the formalin-injected paw blocked PNU282987-induced antinociception. Conversely, exogenous administration of the naturally occurring PPAR-α agonist PEA potentiated the antinociceptive effects of PNU282987. In contrast, the cannabinoid CB1 antagonist rimonabant and the CB2 antagonist SR144528 failed to reverse the antinociceptive effects of PNU282987. These findings suggest that PPAR-α plays a key role in a putative antinociceptive α7 nicotinic signaling pathway. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Using Satellite Data to Represent Tropical Instability Waves (TIWs-Induced Wind for Ocean Modeling: A Negative Feedback onto TIW Activity in the Pacific

    Directory of Open Access Journals (Sweden)

    Jinzhong Min

    2013-05-01

    Full Text Available Recent satellite data and modeling studies indicate a pronounced role Tropical Instability Waves (TIW-induced wind feedback plays in the tropical Pacific climate system. Previously, remotely sensed data were used to derive a diagnostic model for TIW-induced wind stress perturbations (τTIW, which was embedded into an ocean general circulation model (OGCM to take into account TIW-induced ocean-atmosphere coupling in the tropical Pacific. While the previous paper by Zhang (2013 is concerned with the effect on the mean ocean state, the present paper is devoted to using the embedded system to examine the effects on TIW activity in the ocean, with τTIW being interactively determined from TIW-scale sea surface temperature (SSTTIW fields generated in the OGCM, written as τTIW = αTIW·F(SSTTIW, where αTIW is a scalar parameter introduced to represent the τTIW forcing intensity. Sensitivity experiments with varying αTIW (representing TIW-scale wind feedback strength are performed to illustrate a negative feedback induced by TIW-scale air-sea coupling and its relationship with TIW variability in the ocean. Consistent with previous modeling studies, TIW wind feedback tends to have a damping effect on TIWs in the ocean, with a general inverse relationship between the τTIW intensity and TIWs. It is further shown that TIW-scale coupling does not vary linearly with αTIW: the coupling increases linearly with intensifying τTIW forcing at low values of αTIW (in a weak τTIW forcing regime; it becomes saturated at a certain value of αTIW; it decreases when αTIW goes above a threshold value as the τTIW forcing increases further. This work presents a clear demonstration of using satellite data to effectively represent TIW-scale wind feedback and its multi-scale interactions with large-scale ocean processes in the tropical Pacific.

  5. Conflicto psíquico y actividad representativa como ejes del tratamiento psicopedagógico Psychical conflict and representative activity as central core of psychopedagogical treatment

    Directory of Open Access Journals (Sweden)

    María Victoria Rego

    2007-12-01

    Full Text Available El propósito de este artículo es presentar un modo de análisis de las transformaciones en la producción simbólica de niños con problemas de aprendizaje que asisten a tratamiento psicopedagógico grupal en el marco del Servicio de Asistencia Psicopedagógica de la Cátedra de Psicopedagogía Clínica de la Facultad de Psicología. Se plantean dos categorías para dicho análisis: conflicto psíquico y actividad representativa. A partir de las mismas se busca dar cuenta de un particular modo de interpretación teórico - clínico de las características que presentan los procesos de simbolización en niños con dificultades en sus aprendizajes, así como de sus cambios psíquicos y transformaciones a lo largo de un año de tratamiento. Se plantea como hipótesis que la inclusión del conflicto en la actividad representativa despliega las restricciones simbólicas de estos niños, hacia nuevos modos de representación más dinámicos y enriquecedores. Finalmente se muestra también un caso clínico para ampliar y profundizar la presentación teórica.The purpose of this article is to show the way of analysing the changes of the symbolic production in children who suffer from learning disorders and attend to the Assistance Program which belongs to the Psychopedagogical Clinic Department of Psychology School. Two categories are put forward: psychical conflict and representative activity. Both are used in a particular way of theoretical and clinical analysis for the features presented in the symbolic process of these children and in their psychical changes along one year of treatment as well. One hypothesis is that the inclusion of the conflict in the representative activity displays the symbolical obstacles and restrictions, to create new dynamic ways of representation and performance. To finish, a clinical case is shown, to amplify and deepen this presentation.

  6. Suppression of Wnt signaling by the miR-29 family is mediated by demethylation of WIF-1 in non-small-cell lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Min [Department of Respiratory Medicine, Shanghai Tenth People’s Hospital, Tongji University, Shanghai 200072 (China); Wu, Junjie, E-mail: wujunjiesh@126.com [Department of Pneumology, Changhai Hospital of Shanghai, Second Military Medical University, Shanghai 200433 (China); State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Sciences, Fudan University, Shanghai 200433 (China); Cai, Yong, E-mail: dryongcai@126.com [Department of Radiation Oncology, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433 (China)

    2013-09-06

    Highlights: •Dnmt3A and Dnmt3B are involved in the down-regulation of WIF-1 expression in non-small-cell lung cancer. •MiR-29 family members could restore WIF-1 expression through demethylation. •MiR-29s suppress Wnt/β-catenin signaling pathway and inhibit tumor growth. •The expression of miR-29a and miR-29b could be regulated partially in a positive feedback loop. -- Abstract: Wnt inhibitory factor-1 (WIF-1) silencing induced by promoter hypermethylation is a common mechanism of aberrant activation of the Wnt signaling pathway in non-small-cell lung cancer (NSCLC). However, the activity of regulators associated with the methylation of the WIF-1 gene remains unclear. Here, we investigated the role of three DNA methyltransferases (DNMT1, DNMT3A and DNMT3B) in the expression of WIF-1. The three DNMTs were up-regulated in NSCLC tumor tissues and suppression of DNMT3A and DNMT3B restored the expression of WIF-1 in NSCLC cells. The miR-29 family (miR-29a, -29b, and -29c), which negatively regulates DNMT3A and DNMT3B, was examined in association with the Wnt/β-catenin signaling pathway. A positive correlation between the expression of WIF-1 and that of MiR-29s was observed in NSCLC tissues. Methylation-specific PCR and Western blotting indicated that miR-29s positively regulate WIF-1 expression by inhibiting the methylation of its promoter. Furthermore, miR-29 overexpression downregulated β-catenin expression, inhibited cell proliferation and induced apoptosis. The expression of miR-29a and miR-29b was partially regulated by DNMT3A and DNMT3B in a positive feedback loop. Taken together, our findings show that miR-29s suppress the Wnt signaling pathway through demethylation of WIF-1 in NSCLC.

  7. Demethylation of Circulating Estrogen Receptor Alpha Gene in Cerebral Ischemic Stroke.

    Directory of Open Access Journals (Sweden)

    Hsiu-Fen Lin

    Full Text Available Estrogen is involved in neuron plasticity and can promote neuronal survival in stroke. Its actions are mostly exerted via estrogen receptor alpha (ERα. Previous animal studies have shown that ERα is upregulated by DNA demethylation following ischemic injury. This study investigated the methylation levels in the ERα promoter in the peripheral blood of ischemic stroke patients.The study included 201 ischemic stroke patients, and 217 age- and sex-comparable healthy controls. The quantitative methylation level in the 14 CpG sites of the ERα promoter was measured by pyrosequencing in each participant. Multivariate regression model was used to adjust for stroke traditional risk factors. Stroke subtypes and sex-specific analysis were also conducted.The results demonstrated that the stroke cases had a lower ERα methylation level than controls in all 14 CpG sites, and site 13 and site 14 had significant adjusted p-values of 0.035 and 0.026, respectively. Stroke subtypes analysis showed that large-artery atherosclerosis and cardio-embolic subtypes had significantly lower methylation levels than the healthy controls at CpG site 5, site 9, site 12, site 13 and site 14 with adjusted p = 0.039, 0.009, 0.025, 0.046 and 0.027 respectively. However, the methylation level for the patients with small vessel subtype was not significant. We combined the methylation data from the above five sites for further sex-specific analysis. The results showed that the significant association only existed in women (adjusted p = 0.011, but not in men (adjusted p = 0.300.Female stroke cases have lower ERα methylation levels than those in the controls, especially in large-artery and cardio-embolic stroke subtypes. The study implies that women suffering from ischemic stroke of specific subtype may undergo different protective mechanisms to reduce the brain injury.

  8. H3K4me3 demethylation by the histone demethylase KDM5C/JARID1C promotes DNA replication origin firing.

    Science.gov (United States)

    Rondinelli, Beatrice; Schwerer, Hélène; Antonini, Elena; Gaviraghi, Marco; Lupi, Alessio; Frenquelli, Michela; Cittaro, Davide; Segalla, Simona; Lemaitre, Jean-Marc; Tonon, Giovanni

    2015-03-11

    DNA replication is a tightly regulated process that initiates from multiple replication origins and leads to the faithful transmission of the genetic material. For proper DNA replication, the chromatin surrounding origins needs to be remodeled. However, remarkably little is known on which epigenetic changes are required to allow the firing of replication origins. Here, we show that the histone demethylase KDM5C/JARID1C is required for proper DNA replication at early origins. JARID1C dictates the assembly of the pre-initiation complex, driving the binding to chromatin of the pre-initiation proteins CDC45 and PCNA, through the demethylation of the histone mark H3K4me3. Fork activation and histone H4 acetylation, additional early events involved in DNA replication, are not affected by JARID1C downregulation. All together, these data point to a prominent role for JARID1C in a specific phase of DNA replication in mammalian cells, through its demethylase activity on H3K4me3.

  9. The Akt/mTOR/p70S6K pathway is activated in IgA nephropathy and rapamycin may represent a viable treatment option.

    Science.gov (United States)

    Tian, Jihua; Wang, Yanhong; Guo, Haixiu; Li, Rongshan

    2015-12-01

    IgA nephropathy (IgAN) is one of the most frequent forms of glomerulonephritis, and 20 to 40% of patients progress to end-stage renal disease (ESRD) within 20 years of disease onset. However, little is known about the molecular pathways involved in the altered physiology of mesangial cells during IgAN progression. This study was designed to explore the role of mTOR signaling and the potential of targeted rapamycin therapy in a rat model of IgAN. After establishing an IgA nephropathy model, the rats were randomly divided into four groups: control, control+rapamycin, IgAN and IgA+rapamycin. Western blotting and immunohistochemistry were performed to determine phospho-Akt, p70S6K and S6 protein levels. Coomassie Brilliant Blue was utilized to measure 24-h urinary protein levels. The biochemical parameters of the rats were analyzed with an autoanalyzer. To evaluate IgA deposition in the glomeruli, FITC-conjugated goat anti-rat IgA antibody was used for direct immunofluorescence. Cellular proliferation and the mesangial matrix in glomeruli were assayed via histological and morphometric procedures. Our results showed that p70S6K, S6 and Akt phosphorylation were significantly upregulated in IgAN rats, and rapamycin effectively inhibited p70S6K and S6 phosphorylation. A low dose of the mTOR inhibitor rapamycin reduced proteinuria, inhibited IgA deposition, and protected kidney function in an IgAN rat model. Low-dose rapamycin treatment corresponded to significantly lower cellular proliferation rates and a decreased mesangial matrix in the glomeruli. In conclusion, the Akt/mTOR/p70S6K pathway was activated in IgAN, and our findings suggested that rapamycin may represent a viable option for the treatment of IgAN.

  10. Demethylation of oligogalacturonides by FaPE1 in the fruits of the wild strawberry Fragaria vesca triggers metabolic and transcriptional changes associated with defence and development of the fruit.

    Science.gov (United States)

    Osorio, Sonia; Bombarely, Aureliano; Giavalisco, Patrick; Usadel, Björn; Stephens, Camilla; Aragüez, Irene; Medina-Escobar, Nieves; Botella, Miguel A; Fernie, Alisdair R; Valpuesta, Victoriano

    2011-05-01

    Ectopic expression of the strawberry (Fragaria×ananassa) gene FaPE1 encoding pectin methyl esterase produced in the wild species Fragaria vesca partially demethylated oligogalacturonides (OGAs), which conferred partial resistance of ripe fruits to the fungus Botrytis cinerea. Analyses of metabolic and transcriptional changes in the receptacle of the transgenic fruits revealed channelling of metabolites to aspartate and aromatic amino acids as well as phenolics, flavanones, and sesquiterpenoids, which was in parallel with the increased expression of some genes related to plant defence. The results illustrate the changes associated with resistance to B. cinerea in the transgenic F. vesca. These changes were accompanied by a significant decrease in the auxin content of the receptacle of the ripe fruits of transgenic F. vesca, and enhanced expression of some auxin-repressed genes. The role of these OGAs in fruit development was revealed by the larger size of the ripe fruits in transgenic F. vesca. When taken together these results show that in cultivated F. ananassa FaPE1 participates in the de-esterification of pectins and the generation of partially demethylated OGAs, which might reinforce the plant defence system and play an active role in fruit development.

  11. Inhibition of CYP2D6-mediated tramadol O-demethylation in methadone but not buprenorphine maintenance patients

    Science.gov (United States)

    Coller, Janet K; Michalakas, Jennifer R; James, Heather M; Farquharson, Aaron L; Colvill, Joel; White, Jason M; Somogyi, Andrew A

    2012-01-01

    AIMS To compare the O- (CYP2D6 mediated) and N- (CYP3A4 mediated) demethylation metabolism of tramadol between methadone and buprenorphine maintained CYP2D6 extensive metabolizer subjects. METHODS Nine methadone and seven buprenorphine maintained subjects received a single 100 mg dose of tramadol hydrochloride. Blood was collected at 4 h and assayed for tramadol, methadone, buprenorphine and norbuprenorphine (where appropriate) and all urine over 4 h was assayed for tramadol and its M1 and M2 metabolites. RESULTS The urinary metabolic ratio [median (range)] for O-demethylation (M1) was significantly lower (P= 0.0002, probability score 1.0) in the subjects taking methadone [0.071 (0.012–0.103)] compared with those taking buprenorphine [0.192 (0.108–0.392)], but there was no significant difference (P= 0.21, probability score 0.69) in N-demethylation (M2). The percentage of dose [median (range)] recovered as M1 was significantly lower in subjects taking methadone compared with buprenorphine (0.069 (0.044–0.093) and 0.126 (0.069–0.187), respectively, P= 0.04, probability score 0.19), M2 was significantly higher in subjects taking methadone compared with buprenorphine (0.048 (0.033–0.085) and 0.033 (0.014–0.049), respectively, P= 0.04, probability score 0.81). Tramadol was similar (0.901 (0.635–1.30) and 0.685 (0.347–1.04), respectively, P= 0.35, probability score 0.65). CONCLUSIONS Methadone inhibited the CYP2D6-mediated metabolism of tramadol to M1. Hence, as the degree of opioid analgesia is largely dependent on M1 formation, methadone maintenance patients may not receive adequate analgesia from oral tramadol. PMID:22369095

  12. Global demethylation of rat chondrosarcoma cells after treatment with 5-aza-2'-deoxycytidine results in increased tumorigenicity.

    Directory of Open Access Journals (Sweden)

    Christopher A Hamm

    Full Text Available Abnormal patterns of DNA methylation are observed in several types of human cancer. While localized DNA methylation of CpG islands has been associated with gene silencing, the effect that genome-wide loss of methylation has on tumorigenesis is not completely known. To examine its effect on tumorigenesis, we induced DNA demethylation in a rat model of human chondrosarcoma using 5-aza-2-deoxycytidine. Rat specific pyrosequencing assays were utilized to assess the methylation levels in both LINEs and satellite DNA sequences following 5-aza-2-deoxycytidine treatment. Loss of DNA methylation was accompanied by an increase in invasiveness of the rat chondrosarcoma cells, in vitro, as well as by an increase in tumor growth in vivo. Subsequent microarray analysis provided insight into the gene expression changes that result from 5-aza-2-deoxycytidine induced DNA demethylation. In particular, two genes that may function in tumorigenesis, sox-2 and midkine, were expressed at low levels in control cells but upon 5-aza-2-deoxycytidine treatment these genes became overexpressed. Promoter region DNA analysis revealed that these genes were methylated in control cells but became demethylated following 5-aza-2-deoxycytidine treatment. Following withdrawal of 5-aza-2-deoxycytidine, the rat chondrosarcoma cells reestablished global DNA methylation levels that were comparable to that of control cells. Concurrently, invasiveness of the rat chondrosarcoma cells, in vitro, decreased to a level indistinguishable to that of control cells. Taken together these experiments demonstrate that global DNA hypomethylation induced by 5-aza-2-deoxycytidine may promote specific aspects of tumorigenesis in rat chondrosarcoma cells.

  13. The role of highly purified forms of rat liver cytochrome P-450 in the dimethylation of dimethylnitrosamine and its activation to mutagens.

    Science.gov (United States)

    Masson, H A; Ioannides, C; Gibson, G G

    1983-06-01

    Highly purified NADPH-cytochrome P-450 reductase and the major phenobarbital (PB) and beta-naphthoflavone (beta NF) forms of cytochrome P-450 were used in reconstituted systems to study the demethylation and subsequent activation of dimethylnitrosamine (DMN) to mutagenic intermediates. Both forms of cytochrome P-450 were active in the demethylation of DMN, cytochrome P-450 from PB-treated animals being more efficient, generating nearly twice as much formaldehyde per nmol of haemoprotein. Neither form of the cytochrome could activate DMN to mutagens in the Ames test. These findings indicate that DMN demethylation does not lead to its activation to mutagenic products.

  14. Vitamin C protects against UV irradiation-induced apoptosis through reactivating silenced tumor suppressor genes p21 and p16 in a Tet-dependent DNA demethylation manner in human skin cancer cells.

    Science.gov (United States)

    Lin, Jin-ran; Qin, Hai-hong; Wu, Wen-yu; He, Shu-juan; Xu, Jin-hua

    2014-08-01

    DNA methylation plays important roles in various kinds of carcinogenesis. Vitamin C could induce Tet-dependent DNA demethylation in embryonic stem cells. Therefore, the antagonizing activity of vitamin C on ultraviolet (UV)-induced apoptosis was investigated in this study. Apoptosis of human epidermoid carcinoma A431 cells and p16-knockout (KO) or p21-KO fibroblasts was assessed by a fluorescence-activated cell sorter. Real-time PCR and western blot were used to determine the relative expression levels of p12, p21, and Tet1/2/3 genes. The global DNA methylation levels were determined using MethylFlash Methylated DNA Quantification Kit in A431 cells with or without vitamin C treatment. To examine the DNA demethylation activity of vitamin C, DNA immunoprecipitation (DIP)-qPCR was performed to determine the relative levels of 5-methylcytosine (5mC) or 5-hydroxymethylcytosine (5hmC) in p16 and p21 promoter regions containing cytosine-phosphorothiolated guanine (CpG) islands. The increasing apoptosis of A431 cells under prolonged UV irradiation was remarkably decreased by the combination of vitamin C treatment, suggesting that vitamin C protects against UV-induced apoptosis. Concurrently, vitamin C induced a significant reduction of global DNA methylation in a time- and dose-dependent manner in A431 cells. Vitamin C also reactivated the expression of p16 and p21 at mRNA and protein levels. Mechanistically, about 27% 5hmC-positive cells were observed in vitamin C-treated A431 cells, and the 5hmC enrichment at p16 and p21 promoter regions was also largely increased by vitamin C. Moreover, the expression of p16 and p21 was decreased in Tet1/2 double-knockdown cells, in which the inhibitory effect of vitamin C on UV-induced apoptosis was dismissed. Furthermore, the inhibition of UV-induced apoptosis on vitamin C treatment nearly disappeared in p16- or p21-knockout primary cultured fibroblasts. These results demonstrate that vitamin C effectively antagonizes UV

  15. Testing Theory of Planned Behavior and Neo-Socioanalytic Theory models of trait activity, industriousness, exercise social cognitions, exercise intentions, and physical activity in a representative U.S. sample

    Science.gov (United States)

    Vo, Phuong T.; Bogg, Tim

    2015-01-01

    Prior research identified assorted relations between trait and social cognition models of personality and engagement in physical activity. Using a representative U.S. sample (N = 957), the goal of the present study was to test two alternative structural models of the relationships among the extraversion-related facet of activity, the conscientiousness-related facet of industriousness, social cognitions from the Theory of Planned Behavior (perceived behavioral control, affective attitudes, subjective norms, intentions), Social Cognitive Theory (self-efficacy, outcome expectancies), and the Transtheoretical Model (behavioral processes of change), and engagement in physical activity. Path analyses with bootstrapping procedures were used to model direct and indirect effects of trait and social cognition constructs on physical activity through two distinct frameworks – the Theory of Planned Behavior and Neo-Socioanalytic Theory. While both models showed good internal fit, comparative model information criteria showed the Theory-of-Planned-Behavior-informed model provided a better fit. In the model, social cognitions fully mediated the relationships from the activity facet and industriousness to intentions for and engagement in physical activity, such that the relationships were primarily maintained by positive affective evaluations, positive expected outcomes, and confidence in overcoming barriers related to physical activity engagement. The resultant model – termed the Disposition-Belief-Motivation model– is proposed as a useful framework for organizing and integrating personality trait facets and social cognitions from various theoretical perspectives to investigate the expression of health-related behaviors, such as physical activity. Moreover, the results are discussed in terms of extending the application of the Disposition-Belief-Motivation model to longitudinal and intervention designs for physical activity engagement. PMID:26300811

  16. Testing Theory of Planned Behavior and Neo-Socioanalytic Theory models of trait activity, industriousness, exercise social cognitions, exercise intentions, and physical activity in a representative U.S. sample.

    Science.gov (United States)

    Vo, Phuong T; Bogg, Tim

    2015-01-01

    Prior research identified assorted relations between trait and social cognition models of personality and engagement in physical activity. Using a representative U.S. sample (N = 957), the goal of the present study was to test two alternative structural models of the relationships among the extraversion-related facet of activity, the conscientiousness-related facet of industriousness, social cognitions from the Theory of Planned Behavior (perceived behavioral control, affective attitudes, subjective norms, intentions), Social Cognitive Theory (self-efficacy, outcome expectancies), and the Transtheoretical Model (behavioral processes of change), and engagement in physical activity. Path analyses with bootstrapping procedures were used to model direct and indirect effects of trait and social cognition constructs on physical activity through two distinct frameworks - the Theory of Planned Behavior and Neo-Socioanalytic Theory. While both models showed good internal fit, comparative model information criteria showed the Theory-of-Planned-Behavior-informed model provided a better fit. In the model, social cognitions fully mediated the relationships from the activity facet and industriousness to intentions for and engagement in physical activity, such that the relationships were primarily maintained by positive affective evaluations, positive expected outcomes, and confidence in overcoming barriers related to physical activity engagement. The resultant model - termed the Disposition-Belief-Motivation model- is proposed as a useful framework for organizing and integrating personality trait facets and social cognitions from various theoretical perspectives to investigate the expression of health-related behaviors, such as physical activity. Moreover, the results are discussed in terms of extending the application of the Disposition-Belief-Motivation model to longitudinal and intervention designs for physical activity engagement.

  17. Testing Theory of Planned Behavior and Neo-Socioanalytic Theory models of trait activity, industriousness, exercise social cognitions, exercise intentions, and physical activity in a representative U.S. sample

    Directory of Open Access Journals (Sweden)

    Phuong Thi Vo

    2015-08-01

    Full Text Available Prior research identified assorted relations between trait and social cognition models of personality and engagement in physical activity. Using a representative U.S. sample (N = 957, the goal of the present study was to test two alternative structural models of the relationships among the extraversion-related facet of activity, the conscientiousness-related facet of industriousness, social cognitions from the Theory of Planned Behavior (perceived behavioral control, affective attitudes, subjective norms, intentions, Social Cognitive Theory (self-efficacy, outcome expectancies, and the Transtheoretical Model (behavioral processes of change, and engagement in physical activity. Path analyses with bootstrapping procedures were used to model direct and indirect effects of trait and social cognition constructs on physical activity through two distinct frameworks – the Theory of Planned Behavior and Neo-Socioanalytic Theory. While both models showed good internal fit, comparative model information criteria showed the Theory-of-Planned-Behavior-informed model provided a better fit. In the model, social cognitions fully mediated the relationships from the activity facet and industriousness to intentions for and engagement in physical activity, such that the relationships were primarily maintained by positive affective evaluations, positive expected outcomes, and confidence in overcoming barriers related to physical activity engagement. The resultant model – termed the Disposition-Belief-Motivation model – is proposed as a useful framework for organizing and integrating personality trait facets and social cognitions from various theoretical perspectives to investigate the expression of health-related behaviors, such as physical activity. Moreover, the results are discussed in terms of extending the application of the Disposition-Belief-Motivation model to longitudinal and intervention designs for physical activity engagement.

  18. Role of heme oxygenase-1 in demethylating effects on SKM-1 cells induced by decitabine.

    Science.gov (United States)

    Gao, R; Ma, D; Wang, P; Sun, J; Wang, J S; Fang, Q

    2015-12-22

    We evaluated the influence of heme oxygenase-1 (HO-1) gene inhibition in myelodysplastic syndrome (MDS) cell line SKM-1 on enhancement of the demethylating effects of decitabine on p15, and explored the possible mechanism. DNMT1 gene expression in SKM-1 cells was silenced by being transfected by a constructed siRNA with liposomes. The proliferation inhibition rates after drug treatment were detected by cell counting kit-8 assay. The apoptotic rates were detected by Annexin V/PI assay with flow cytometry. The expressions of p16, p15, TP73, CDH1, ESR1, and PDLIM4 mRNAs were detected by real-time PCR, and those of HO-1, DNMT1, DNMT3A, DNMT3B, HDAC, and p15 proteins were measured by western blot. The degree of methylation of the p15 gene was analyzed by using methylation-specific PCR (MSP). CCK-8 assay showed that after HO-1 gene expression was inhibited; the proliferation rate of SKM-1 cells treated by decitabine (70.91 ± 0.05%) was significantly higher than that of the control group (53.67 ± 0.05%). Flow cytometry showed that the apoptotic rate of SKM- 1 cells treated by decitabine in combination with HO-1 expression inhibition (44.25 ± 0.05%) exceeded that of the cells treated by this drug alone (37.70 ± 0.05%). MSP showed that inhibiting HO-1 expression significantly increased the degree of methylation of the p15 gene. As suggested by western blot, the degree of methylation of the p15 protein was changed after decitabine treatment when the expression of the HO-1 protein was changed, being associated with the affected DNMT1 expression. Inhibited HO-1 expression attenuated the hypermethylation of CDKN2B by suppressing DNMT1, which was conducive to treatment by cooperating with decitabine. In conclusion, the findings of this study provide valuable experimental evidence for targeted MDS therapy, and a theoretical basis for further studies.

  19. Synergism between demethylation inhibitor fungicides or gibberellin inhibitor plant growth regulators and bifenthrin in a pyrethroid-resistant population of Listronotus maculicollis (Coleoptera: Curculionidae).

    Science.gov (United States)

    Ramoutar, D; Cowles, R S; Requintina, E; Alm, S R

    2010-10-01

    In 2007-2008, the "annual bluegrass weevil," Listronotus maculicollis Kirby (Coleoptera: Curculionidae), a serious pest of Poa annua L. (Poales: Poaceae) on U.S. golf courses, was shown to be resistant to two pyrethroids, bifenthrin and lambda-cyhalothrin. In 2008, we showed that bifenthrin resistance was principally mediated by oxidase detoxification (cytochrome P450 [P450]). P450s can be inhibited by demethylation inhibitor fungicides and gibberellin inhibitor plant growth regulators, both of which are commonly used on golf courses. We tested these compounds for synergistic activity with bifenthin against a pyrethroid-resistant population of L. maculicollis. The LD50 value for bifenthrin was significantly reduced from 87 ng per insect (without synergists) to 9.6-40 ng per insect after exposure to the fungicides fenarimol, fenpropimorph, prochloraz, propiconazole, and pyrifenox and the plant growth regulators flurprimidol, paclobutrazol, and trinexapac-ethyl. Simulated field exposure with formulated products registered for use on turf revealed enhanced mortality when adult weevils were exposed to bifenthrin (25% mortality, presented alone) combined with field dosages of propiconizole, fenarimol, flurprimidol, or trinexapac-ethyl (range, 49-70% mortality).

  20. Vitamin C down-regulate apo(a) expression via Tet2-dependent DNA demethylation in HepG2 cells.

    Science.gov (United States)

    Qu, Kai; Ma, Xiao-Feng; Li, Guo-Hua; Zhang, Hai; Liu, Ya-Mi; Zhang, Kai; Zeng, Jun-Fa; Lei, Jian-Jun; Wei, Dang-Heng; Wang, Zuo

    2017-05-01

    Lipoprotein(a)[Lp(a)] is a risk factor for coronary heart diseases. However, the metabolism of this protein remains poorly understood. Efficient and specific drugs that can decrease high plasma levels of Lp(a) have not been developed yet. Vitamin C is responsible for maintaining the catalytic activity of a group of iron and 2-oxoglutarate (2OG)-dependent dioxygenases and induces the generation of 5-hydroxymethylcytosine (5hmC) via Ten-eleven translocation (Tet) dioxygenases. In addition, It has been reported vitamin C deficiency induces atherosclerosis and increases Lp(a) and apo(a) plasma levels in Lp(a)+ mice. However, the mechanism is still unclear. In this study, we investigated the effects of vitamin C on apo(a) expression and the possible molecular mechanism of vitamin C that influences apolipoprotein(a) [apo(a)] biosynthesis in HepG2 cells. Results showed that vitamin C significantly inhibited the expression and secretion levels of apo(a). Vitamin C can also increase ELK1 expression and hydroxymethylation of ELK1 promoter and the globle DNA in HepG2 cells. In addition, the effects of vitamin C inhibiting the apo(a) expression were attenuated by ELK1siRNA and Tet2siRNA. These results suggested vitamin C down-regulate apo(a) expression via Tet2-dependent DNA demethylation in HepG2 cells.

  1. Modulators of membrane drug transporters potentiate the activity of the DMI fungicide oxpoconazole against Botrytis cinerea

    NARCIS (Netherlands)

    Hayashi, K.; Schoonbeek, H.; Waard, de M.A.

    2003-01-01

    Modulators known to reduce multidrug resistance in tumour cells were tested for their potency to synergize the fungitoxic activity of the fungicide oxpoconazole, a sterol demethylation inhibitor (DMI), against Botrytis cinerea Pers. Chlorpromazine, a phenothiazine compound known as a calmodulin

  2. List of Accredited Representatives

    Data.gov (United States)

    Department of Veterans Affairs — VA accreditation is for the sole purpose of providing representation services to claimants before VA and does not imply that a representative is qualified to provide...

  3. The representative animal

    OpenAIRE

    Harrison, J M

    1994-01-01

    The anthropocentric approach to the study of animal behavior uses representative nonhuman animals to understand human behavior. This approach raises problems concerning the comparison of the behavior of two different species. The datum of behavior analysis is the behavior of humans and representative animal phenotypes. The behavioral phenotype is the product of the ontogeny and phylogeny of each species, and this requires that contributions of genotype as well as behavioral history to experim...

  4. [Advance directives. Representatives' opinions].

    Science.gov (United States)

    Busquets I Font, J M; Hernando Robles, P; Font I Canals, R; Diestre Ortin, G; Quintana, S

    The use and usefulness of Advance Directives has led to a lot of controversy about their validity and effectiveness. Those areas are unexplored in our country from the perspective of representatives. To determine the opinion of the representatives appointed in a registered Statement of Advance Directives (SAD) on the use of this document. Telephone survey of representatives of 146 already dead people and who, since February 2012, had registered a SAD document. More the two-thirds (98) of respondents recalled that the SAD was consulted, with 86 (58.9%) saying that their opinion as representative was consulted, and 120 (82.1%) believe that the patient's will was respected. Of those interviewed, 102 (69.9%) believe that patients who had previously planned their care using a SAD had a good death, with 33 (22.4%) saying it could have been better, and 10 (6.9%) believe they suffered greatly. The SAD were mostly respected and consulted, and possibly this is related to the fact that most of the representatives declare that the death of those they represented was perceived as comfortable. It would be desirable to conduct further studies addressed at health personnel in order to know their perceptions regarding the use of Advance Directives in the process of dying. Copyright © 2016 SECA. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. Interleukin-4 Induces CpG Site-Specific Demethylation of the Pendrin Promoter in Primary Human Bronchial Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Giada Scantamburlo

    2017-03-01

    Full Text Available Pendrin is upregulated in bronchial epithelial cells following IL-4 stimulation via binding of STAT6 to an N4 GAS motif. Basal CpG methylation of the pendrin promoter is cell-specific. We studied if a correlation exists between IL-4 sensitivity and the CpG methylation status of the pendrin promoter in human bronchial epithelial cell models. Methods: Real-time PCR and pyrosequencing were used to respectively quantify pendrin mRNA levels and methylation of pendrin promoter, with and without IL-4 stimulation, in healthy and diseased primary HBE cells, as well as NCI-H292 cells. Results: Increases in pendrin mRNA after IL-4 stimulation was more robust in NCI-H292 cells than in primary cells. The amount of gDNA methylated varied greatly between the cell types. In particular, CpG site 90 located near the N4 GAS motif was highly methylated in the primary cells. An additional CpG site (90bis, created by a SNP, was found only in the primary cells. IL-4 stimulation resulted in dramatic demethylation of CpG sites 90 and 90bis in the primary cells. Conclusions: IL-4 induces demethylation of specific CpG sites within the pendrin promoter. These epigenetic alterations are cell type specific, and may in part dictate pendrin mRNA transcription.

  6. Induced Pib Expression and Resistance to Magnaporthe grisea are Compromised by Cytosine Demethylation at Critical Promoter Regions in Rice.

    Science.gov (United States)

    Li, Yuan; Xia, Qiong; Kou, Hongping; Wang, Dan; Lin, Xiuyun; Wu, Ying; Xu, Chunming; Xing, Shaochen; Liu, Bao

    2011-10-01

    Pib is a well-characterized rice blast-resistance gene belonging to the nucleotide binding site (NBS) and leucine-rich repeat (LRR) superfamily. Expression of Pib was low under non-challenged conditions, but strongly induced by the blast-causing fungal pathogen Magnaporthe grisea, thereby conferring resistance to the pathogen. It is generally established that cytosine methylation of the promoter-region often plays a repressive role in modulating expression of the gene in question. We report here that two critical regions of the Pib promoter were heavily CG cytosine-methylated in both cultivars studied. Surprisingly, induced expression of Pib by M. grisea infection did not entail its promoter demethylation, and partial demethylation by 5-azacytidine-treatment actually reduced Pib expression relative to wild-type plants. Accordingly, the blast disease-resistance was compromised in the 5'-azaC-treated plants relative to wild-type. In contrast, the disease susceptibility was not affected by the 5'-azaC treatment in another two rice cultivars that did not contain the Pib gene, ruling out effects of other R genes and non-specific genotoxic effects by the drug-treatment as a cause for the compromised Pib-conditioned blast-resistance. Taken together, our results suggest that promoter DNA methylation plays a novel enhancing role in conditioning high-level of induced expression of the Pib gene in times of M. grisea infection, and its conferred resistance to the pathogen.

  7. Demethylation restores SN38 sensitivity in cells with acquired resistance to SN38 derived from human cervical squamous cancer cells

    Science.gov (United States)

    TANAKA, TETSUJI; BAI, TAO; TOUJIMA, SAORI; UTSUNOMIYA, TOMOKO; MATSUOKA, TOSHIHIDE; KOBAYASHI, AYA; YAMAMOTO, MADOKA; SASAKI, NORIYUKI; TANIZAKI, YUKO; UTSUNOMIYA, HIROTOSHI; TANAKA, JUNKO; YUKAWA, KAZUNORI

    2012-01-01

    Using seven monoclonal SN38-resistant subclones established from ME180 human cervical squamous cell carcinoma cells, we examined the demethylation effects of 5-aza-2′-deoxycytidine (5-aza-CdR) on the SN38-sensitivity of the cells as well as the expression of death-associated protein kinase (DAPK) in the SN38-resistant cells. The DAPK expression levels were evaluated among parent ME180 cells, SN38-resistant ME180 cells and cisplatin-resistant ME180 cells by methylation-specific DAPK-PCR, quantitative RT-PCR and western blot analysis. The SN38-resistant cells co-treated with SN38 and 5-aza-CdR strongly exhibited enhanced SN38-sensitivities resembling those found in the parent cells. In the SN38-resistant subclones, no relationships were found between the restored SN38 sensitivity and hypermethylation of the DAPK promoter, DAPK mRNA expression, DAPK protein expression and induction of DAPK protein after 5-aza-CdR treatment, unlike the strong suppression of 5-aza-CdR-induced DAPK protein expression in the cisplatin-resistant subclones. These findings indicate that reversibly methylated molecules, but not DAPK, may regulate SN38 resistance, and that demethylating agents can be strong sensitizing anticancer chemotherapeutic drugs for SN38-resistant cancers. PMID:22246465

  8. [Methylation of FHIT gene promoter region in DNA from plasma of patients with myelodysplastic syndromes and demethylating effect of decitabine].

    Science.gov (United States)

    Deng, Yin-Fen; Zhang, Lei; Zhang, Xiu-Qun; Hu, Ming-Qiu; Dai, Dan; Zhang, Xue-Zhong; Xu, Yan-Li

    2012-10-01

    This study was aimed to detect the methylation status of FHIT gene promoter region in the DNA from plasma of patients with myelodysplastic syndrome (MDS), and to investigate the demethylating effect of decitabine. Methylation-specific PCR method was used to detect the methylation status of FHIT gene promoter region in the DNA from plasma of 4 patients with MDS before and after treatment with decitabine plus semis CAG therapy (among them, 1 case of newly diagnosed MDS, 3 cases progressed into acute leukemia). The results indicated that 3 cases were found to have an increased methylation in the promoter region. After treatment with decitabine plus semis CAG, increased methylation was reversed in 2 cases. In 4 cases, 2 cases displayed clinical response. It is concluded that FHIT gene hypermethylation is associated with MDS pathogenesis. Decitabine has demethylating effect on the FHIT gene hypermethylation of plasma from MDS patients. Detecting the methylation status of FHIT gene in DNA from plasma may play a role in MDS auxiliary diagnosis or prognosis.

  9. Representing properties locally.

    Science.gov (United States)

    Solomon, K O; Barsalou, L W

    2001-09-01

    Theories of knowledge such as feature lists, semantic networks, and localist neural nets typically use a single global symbol to represent a property that occurs in multiple concepts. Thus, a global symbol represents mane across HORSE, PONY, and LION. Alternatively, perceptual theories of knowledge, as well as distributed representational systems, assume that properties take different local forms in different concepts. Thus, different local forms of mane exist for HORSE, PONY, and LION, each capturing the specific form that mane takes in its respective concept. Three experiments used the property verification task to assess whether properties are represented globally or locally (e.g., Does a PONY have mane?). If a single global form represents a property, then verifying it in any concept should increase its accessibility and speed its verification later in any other concept. Verifying mane for PONY should benefit as much from having verified mane for LION earlier as from verifying mane for HORSE. If properties are represented locally, however, verifying a property should only benefit from verifying a similar form earlier. Verifying mane for PONY should only benefit from verifying mane for HORSE, not from verifying mane for LION. Findings from three experiments strongly supported local property representation and ruled out the interpretation that object similarity was responsible (e.g., the greater overall similarity between HORSE and PONY than between LION and PONY). The findings further suggest that property representation and verification are complicated phenomena, grounded in sensory-motor simulations.

  10. Representing and Performing Businesses

    DEFF Research Database (Denmark)

    Boll, Karen

    2014-01-01

    and MacKenzie’s idea of performativity. Based on these two approaches, the article demonstrates that the segmentation model represents and performs the businesses as it makes up certain new ways to be a business and as the businesses can be seen as moving targets. Inspired by MacKenzie the argument......This article investigates a segmentation model used by the Danish Tax and Customs Administration to classify businesses’ motivational postures. The article uses two different conceptualisations of performativity to analyse what the model’s segmentations do: Hacking’s notion of making up people...... is that the segmentation model embodies cleverness in that it simultaneously alters what it represents and then represents this altered reality to confirm the accuracy of its own model of the businesses’ postures. Despite the cleverness of the model, it also has a blind spot. The model assumes a world wherein everything...

  11. A symphony on C : orchestrating DNA repair for gene expression via cytosine modification The 2012 IMB Conference: DNA Demethylation, Repair and Beyond Institute of Molecular Biology, Mainz, Germany, 18-21 October 2012

    NARCIS (Netherlands)

    Rots, Marianne G.; Petersen-Mahrt, Svend K.

    2013-01-01

    Headline-grabbing attention has been given to DNA demethylation pathways as new epigenetic mechanisms, with reviews and hypotheses outnumbering research papers. As candidate proteins for DNA demethylation include well-known DNA repair enzymes, it was timely to join epigenetics and DNA repair experts

  12. Motivation and planning as mediators of the relation between social support and physical activity among U.S. adolescents: a nationally representative study

    OpenAIRE

    Li, Kaigang; Iannotti, Ronald J; Haynie, Denise L.; Perlus, Jessamyn G.; Simons-Morton, Bruce G

    2014-01-01

    Background More than half of U.S. high-school students do not meet the moderate and vigorous physical activity (MVPA) 5 hours per week recommendation. The purpose of this study was to determine how individual dimensions (motivation and planning) mediate the relationship of social context with physical activity by integrating available measures of personal characteristic including internal/external motivations (derived from Self-Determination Theory -SDT]) for MVPA, MVPA planning, peer MVPA, a...

  13. Mild Glucose Starvation Induces KDM2A-Mediated H3K36me2 Demethylation through AMPK To Reduce rRNA Transcription and Cell Proliferation.

    Science.gov (United States)

    Tanaka, Yuji; Yano, Hirohisa; Ogasawara, Sachiko; Yoshioka, Sho-Ichi; Imamura, Hiromi; Okamoto, Kengo; Tsuneoka, Makoto

    2015-12-01

    Environmental conditions control rRNA transcription. Previously, we found that serum and glucose deprivation induces KDM2A-mediated H3K36me2 demethylation in the rRNA gene (rDNA) promoter and reduces rRNA transcription in the human breast cancer cell line MCF-7. However, the molecular mechanism and biological significance are still unclear. In the present study, we found that glucose starvation alone induced the KDM2A-dependent reduction of rRNA transcription. The treatment of cells with 2-deoxy-d-glucose, an inhibitor of glycolysis, reduced rRNA transcription and H3K36me2 in the rDNA promoter, both of which were completely dependent on KDM2A in low concentrations of 2-deoxy-d-glucose, that is, mild starvation conditions. The mild starvation induced these KDM2A activities through AMP-activated kinase (AMPK) but did not affect another AMPK effector of rRNA transcription, TIF-IA. In the triple-negative breast cancer cell line MDA-MB-231, the mild starvation also reduced rRNA transcription in a KDM2A-dependent manner. We detected KDM2A in breast cancer tissues irrespective of their estrogen receptor, progesterone receptor, and HER2 status, including triple-negative cancer tissues. In both MCF-7 and MDA-MB-231 cells, mild starvation reduced cell proliferation, and KDM2A knockdown suppressed the reduction of cell proliferation. These results suggest that under mild glucose starvation AMPK induces KDM2A-dependent reduction of rRNA transcription to control cell proliferation.

  14. Comparative in vitro metabolism of methoxychlor in male and female rats: metabolism of demethylated methoxychlor metabolites by precision-cut rat liver slices.

    Science.gov (United States)

    Ohyama, K; Maki, S; Sato, K; Kato, Y

    2005-07-01

    The in vitro metabolism of demethylated methoxychlor (MXC) metabolites, mono-OH-MXC (including (R)- and (S)-isomers) and bis-OH-MXC (mono- and bis-demethylated MXC, respectively), was conducted using precision-cut liver slices to understand the sex-dependent metabolism of MXC in rats. In the study with bis-OH-MXC, the substrate underwent extensive conjugation producing its glucuronide and glucuronide/sulphate diconjugate, and no significant sex differences were found. On the contrary, the metabolism of mono-OH-MXC appeared to exhibit the sex differences in the metabolic profiles. The bis-OH-MXC glucuronide and glucuronide/sulphate diconjugate were major metabolites in male rat, whereas the mono- and bis-OH-MXC glucuronides predominated in the female. The per cent distribution of the demethylated products (sum of bis-OH-MXC derivatives) was approximately 90% for the male (for both isomers) and 81 (R-) to 56% (S-) for the female. The metabolic profiles in (S)-mono-OH-MXC, which is the predominant enantiomer preferentially produced in MXC metabolism in rats, showed a similar pattern to that of MXC compared with the (R)-isomer. The results indicate that the sex differences in oxidative demethylation of the intermediate, (S)-mono-OH-MXC, could be one of the probable reasons for the sex-dependent metabolism of MXC in rats, and the stereo-structural preference of the contributing demethylase enzymes appear to be involved.

  15. Lactococcus lactis TrxD represents a subgroup of thioredoxins prevalent in Gram-positive bacteria containing WCXDC active site motifs

    DEFF Research Database (Denmark)

    Björnberg, Olof; Efler, Petr; Epie, Denis Ebong

    2014-01-01

    Three protein disulfide reductases of the thioredoxin superfamily from the industrially important Gram-positive Lactococcus lactis (LlTrxA, LlTrxD and LlNrdH) are compared to the "classical" thioredoxin from Escherichia coil (EcTrx1). LlTrxA resembles EcTrx1 with a WCGPC active site motif and oth...

  16. [Inhibitory action of divalent copper compounds on cumene hydroperoxide oxidative demethylation of N,N-dimethylaniline by cytochrome P-450].

    Science.gov (United States)

    Kurchenko, V P; Usanov, S A; Metelitsa, D I

    1980-07-01

    The inhibitory action of divalent copper compounds on hydroperoxide-dependent oxidative demethylation of N,N-demethylaniline involving rabbit liver microsomes and highly purified cytochrome P-450 has been studied. CuCl2 is a non-competitive inhibitor, whereas copper tyrosine and lysine complexes are characterized by a mixed type inhibition. The inhibitory action of copper complexes is based on a decrease of cumene hydroperoxide concentration. The reaction results in formation of RO and RO2 radicals destroying cytochrome P-450 CuCl2 (0,001 M) also destroys cytochrome P-450 in the absence of cumene hydroperoxide; the destruction process is characterized by two phases with different rate constants. The nature of the inhibitory action of CuCl2 on N,N-demethylaniline oxidation by hydroperoxides is discussed.

  17. Bone marrow stromal antigen 2 (BST-2 DNA is demethylated in breast tumors and breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Wadie D Mahauad-Fernandez

    Full Text Available Bone marrow stromal antigen 2 (BST-2 is a known anti-viral gene that has been recently identified to be overexpressed in many cancers, including breast cancer. BST-2 is critical for the invasiveness of breast cancer cells and the formation of metastasis in vivo. Although the regulation of BST-2 in immune cells is unraveling, it is unknown how BST-2 expression is regulated in breast cancer. We hypothesized that meta-analyses of BST-2 gene expression and BST-2 DNA methylation profiles would illuminate mechanisms regulating elevated BST-2 expression in breast tumor tissues and cells.We performed comprehensive meta-analyses of BST-2 gene expression and BST-2 DNA methylation in The Cancer Genome Atlas (TCGA and various Gene Expression Omnibus (GEO datasets. BST-2 expression levels and BST-2 DNA methylation status at specific CpG sites on the BST-2 gene were compared for various breast tumor molecular subtypes and breast cancer cell lines.We show that BST-2 gene expression is inversely associated with the methylation status at specific CpG sites in primary breast cancer specimens and breast cancer cell lines. BST-2 demethylation is significantly more prevalent in primary tumors and cancer cells than in normal breast tissues or normal mammary epithelial cells. Demethylation of the BST-2 gene significantly correlates with its mRNA expression. These studies provide the initial evidence that significant differences exist in BST-2 DNA methylation patterns between breast tumors and normal breast tissues, and that BST-2 expression patterns in tumors and cancer cells correlate with hypomethylated BST-2 DNA.Our study suggests that the DNA methylation pattern and expression of BST-2 may play a role in disease pathogenesis and could serve as a biomarker for the diagnosis of breast cancer.

  18. Induced Pib Expression and Resistance to Magnaporthe grisea are Compromised by Cytosine Demethylation at Critical Promoter Regions in Rice

    Institute of Scientific and Technical Information of China (English)

    Yuan Li; Qiong Xia; Hongping Kou; Dan Wang; Xiuyun Lin; Ying Wu; Chunming Xu; Shaochen Xing

    2011-01-01

    Pib is a well-characterized rice blast-resistance gene belonging to the nucleotide binding site (NBS) and leucine-rich repeat (LRR) superfamily.Expression of Pib was low under non-challenged conditions,but strongly induced by the blast-causing fungal pathogen Magnaporthe grisea,thereby conferring resistance to the pathogen.It is generally established that cytosine methylation of the promoter-region often plays a repressive role in modulating expression of the gene in question.We report here that two critical regions of the Pib promoter were heavily CG cytosine-methylated in both cultivars studied.Surprisingly,induced expression of Pib by M.grisea infection did not entail its promoter demethylation,and partial demethylation by 5-azacytidine-treatment actually reduced Pib expression relative to wildtype plants.Accordingly,the blast disease-resistance was compromised in the 5’-azaC-treated plants relative to wild-type.In contrast,the disease susceptibility was not affected by the 5’-azaC treatment in another two rice cultivars that did not contain the Pib gene,ruling out effects of other R genes and non-specific genotoxic effects by the drug-treatment as a cause for the compromised Pib-conditioned blast-resistance.Taken together,our results suggest that promoter DNA methylation plays a novel enhancing role in conditioning high-level of induced expression of the Pib gene in times of M.grisea infection,and its conferred resistance to the pathogen.

  19. The red sport of 'Zaosu' pear and its red-striped pigmentation pattern are associated with demethylation of the PyMYB10 promoter.

    Science.gov (United States)

    Qian, Minjie; Sun, Yongwang; Allan, Andrew C; Teng, Yuanwen; Zhang, Dong

    2014-11-01

    'Zaosu' pear, a hybrid of Pyrus pyrifolia and Pyrus communis, is a popular cultivar developed in China. 'Zaosu Red' is a bud sport of 'Zaosu' with red shoots, young leaves, and fruit. After grafting of 'Zaosu Red', reverse mutations in some branches lead to a loss of colour in leaves and stems. Also, the mature fruit of 'Zaosu Red' exhibits two phenotypes; fully red and striped. The aim of this study was to establish the mechanism of the red colour mutation in 'Zaosu' and the striped pigmentation pattern in fruit of 'Zaosu Red'. The accumulation of anthocyanins and transcript levels of the genes PpUFGT2 and PyMYB10 were highly correlated. The open reading frames (ORF) and promoter regions of these two key genes were cloned and compared between 'Zaosu' and its bud sports, but no sequence differences were found. The R2R3 MYB, PyMYB10, can activate expression of genes encoding enzymes of the anthocyanin biosynthetic pathway. A yeast one-hybrid assay showed that PyMYB10 was associated with the -658 to -172bp fragment of the PpUFGT2 promoter, probably via a MYB binding site (MBS) located at -466bp. The PyMYB10 promoter had lower methylation levels in anthocyanin-rich tissues, indicating that the red bud sport of 'Zaosu' pear and the striped pigmentation pattern of 'Zaosu Red' pear are associated with demethylation of the PyMYB10 promoter. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. DNA methylation and demethylation:current status and future per-spective%DNA甲基化和去甲基化的研究现状及思考

    Institute of Scientific and Technical Information of China (English)

    邓大君

    2014-01-01

    DNA methylation plays important roles in cell differentiation, embryonic development, host adaptations to environmental factors, and pathogenesis through regulation of gene transcription and imprinting, X-inactivation, and de-fense of foreign genetic material invasion, is currently one of the hottest research fields on epigenetics. In the past few years, a number of important findings on DNA methylation have been achieved. These findings include discovery of TETs-catalyzed cytosine hydroxymethylation and its functions in the early embryonic development; the relationship be-tween active and passive DNA demethylation;establishment and maintenance of DNA methylation patterns and their asso-ciations with histone modifications, chromatin configuration, polycomb group proteins and non-coding RNA bindings. DNA methylation has become a new potential biomarker and therapy target.%DNA甲基化通过调节基因转录、印记、X染色体灭活和防御外源性遗传物质入侵等,在细胞分化、胚胎发育、环境适应和疾病发生发展上发挥重要作用,是当前表观遗传学研究的热点领域之一。文章介绍了在过去几年中TET介导的DNA羟甲基化及其在早期胚胎发育中的作用, DNA主动去甲基化及其与被动去甲基化的关系, DNA甲基化建立及其与组蛋白修饰、染色质构象、多梳蛋白和非编码RNA结合等关系方面的重要研究进展和存在的问题以及DNA甲基化的转化应用前景。

  1. Representing distance, consuming distance

    DEFF Research Database (Denmark)

    Larsen, Gunvor Riber

    to mobility and its social context. Such an understanding can be approached through representations, as distance is being represented in various ways, most noticeably in maps and through the notions of space and Otherness. The question this talk subsequently asks is whether these representations of distance...... are being consumed in the contemporary society, in the same way as places, media, cultures and status are being consumed (Urry 1995, Featherstone 2007). An exploration of distance and its representations through contemporary consumption theory could expose what role distance plays in forming...... are present in theoretical and empirical elaborations on mobility, but these remain largely implicit and unchallenged (Bauman 1998). This talk will endeavour to unmask distance as a theoretical entity by exploring ways in which distance can be understood and by discussing distance through its representations...

  2. Using Graph Components Derived from an Associative Concept Dictionary to Predict fMRI Neural Activation Patterns that Represent the Meaning of Nouns.

    Directory of Open Access Journals (Sweden)

    Hiroyuki Akama

    Full Text Available In this study, we introduce an original distance definition for graphs, called the Markov-inverse-F measure (MiF. This measure enables the integration of classical graph theory indices with new knowledge pertaining to structural feature extraction from semantic networks. MiF improves the conventional Jaccard and/or Simpson indices, and reconciles both the geodesic information (random walk and co-occurrence adjustment (degree balance and distribution. We measure the effectiveness of graph-based coefficients through the application of linguistic graph information for a neural activity recorded during conceptual processing in the human brain. Specifically, the MiF distance is computed between each of the nouns used in a previous neural experiment and each of the in-between words in a subgraph derived from the Edinburgh Word Association Thesaurus of English. From the MiF-based information matrix, a machine learning model can accurately obtain a scalar parameter that specifies the degree to which each voxel in (the MRI image of the brain is activated by each word or each principal component of the intermediate semantic features. Furthermore, correlating the voxel information with the MiF-based principal components, a new computational neurolinguistics model with a network connectivity paradigm is created. This allows two dimensions of context space to be incorporated with both semantic and neural distributional representations.

  3. Comparison of the EPIC Physical Activity Questionnaire with combined heart rate and movement sensing in a nationally representative sample of older British adults.

    Directory of Open Access Journals (Sweden)

    Vanesa España-Romero

    Full Text Available OBJECTIVES: To compare physical activity (PA subcomponents from EPIC Physical Activity Questionnaire (EPAQ2 and combined heart rate and movement sensing in older adults. METHODS: Participants aged 60-64y from the MRC National Survey of Health and Development in Great Britain completed EPAQ2, which assesses self-report PA in 4 domains (leisure time, occupation, transportation and domestic life during the past year and wore a combined sensor for 5 consecutive days. Estimates of PA energy expenditure (PAEE, sedentary behaviour, light (LPA and moderate-to-vigorous PA (MVPA were obtained from EPAQ2 and combined sensing and compared. Complete data were available in 1689 participants (52% women. RESULTS: EPAQ2 estimates of PAEE and MVPA were higher than objective estimates and sedentary time and LPA estimates were lower [bias (95% limits of agreement in men and women were 32.3 (-61.5 to 122.6 and 29.0 (-39.2 to 94.6 kJ/kg/day for PAEE; -4.6 (-10.6 to 1.3 and -6.0 (-10.9 to -1.0 h/day for sedentary time; -171.8 (-454.5 to 110.8 and -60.4 (-367.5 to 246.6 min/day for LPA; 91.1 (-159.5 to 341.8 and 55.4 (-117.2 to 228.0 min/day for MVPA]. There were significant positive correlations between all self-reported and objectively assessed PA subcomponents (rho= 0.12 to 0.36; the strongest were observed for MVPA (rho = 0.30 men; rho = 0.36 women and PAEE (rho = 0.26 men; rho = 0.25 women. CONCLUSION: EPAQ2 produces higher estimates of PAEE and MVPA and lower estimates of sedentary and LPA than objective assessment. However, both methodologies rank individuals similarly, suggesting that EPAQ2 may be used in etiological studies in this population.

  4. Representativity of TMA studies.

    Science.gov (United States)

    Sauter, Guido

    2010-01-01

    The smaller the portion of a tumor sample that is analyzed becomes, the higher is the risk of missing important histological or molecular features that might be present only in a subset of tumor cells. Many researchers have, therefore, suggested using larger tissue cores or multiple cores from the same donor tissue to enhance the representativity of TMA studies. However, numerous studies comparing the results of TMA studies with the findings from conventional large sections have shown that all well-established associations between molecular markers and tumor phenotype or patient prognosis can be reproduced with TMAs even if only one single 0.6 mm tissue spot is analyzed. Moreover, the TMA technology has proven to be superior to large section analysis in finding new clinically relevant associations. The high number of samples that are typically included in TMA studies, and the unprecedented degree of standardization during TMA experiments and analysis often give TMA studies an edge over traditional large-section studies.

  5. Urinary Elimination of Coproporphyrins Is Dependent on ABCC2 Polymorphisms and Represents a Potential Biomarker of MRP2 Activity in Humans

    Directory of Open Access Journals (Sweden)

    Isabelle Benz-de Bretagne

    2011-01-01

    Full Text Available MRP2 encoded by ABCC2 gene is involved in the secretion of numerous drugs and endogenous substrates. Patients with Dubin-Johnson syndrome due to mutation in ABCC2 gene have elevated urinary coproporphyrin ratio (UCP I/(I + III. Here we investigated whether this ratio could serve as a biomarker of MRP2 function. Phenotype-genotype relationships were studied in 74 healthy subjects by measuring individual UCP I/(I + III ratio obtained on 24-hour urine and by analyzing five common SNPs in ABCC2 gene. The UCP I/(I + III ratio varied from 14.7% to 46.0% in our population. Subjects with 3972TT genotype had a higher ratio (=.04 than those carrying the C allele. This higher UCP I/(I + III ratio was correlated with a higher level of isomer I excretion. This study provides a proof of concept that UCP I/(I + III ratio can be used as a biomarker of MRP2 function in clinical studies as it provides quantitative information about the in vivo activity of MRP2 in a given patient.

  6. Reductive activation with cysteine represents a chromium(III)-dependent pathway in the induction of genotoxicity by carcinogenic chromium(VI).

    Science.gov (United States)

    Zhitkovich, Anatoly; Quievryn, George; Messer, Joseph; Motylevich, Zhanna

    2002-10-01

    Induction of DNA damage by carcinogenic hexavalent chromium compounds [Cr(VI)] results from its reduction to lower oxidation states. Reductive metabolism of Cr(VI) generates intermediate Cr(V/IV)species, organic radicals, and finally Cr(III), which forms stable complexes with many biological ligands, including DNA. To determine the biological significance of different reaction products, we examined genotoxic responses and the formation of DNA damage during reduction of Cr(VI) by its biological reducer, cysteine. We have found that cysteine-dependent activation of Cr(VI) led to the formation of Cr-DNA and cysteine-Cr-DNA adducts as well as interstrand DNA cross-links. The yield of binary and ternary DNA adducts was relatively constant at different concentrations of Cr(VI) and averaged approximately 54 and 45%, respectively. Interstrand DNA cross-links accounted on average for 1% of adducts, and their yield was even less significant at low Cr(VI) concentrations. Reduction of Cr(VI) in several commonly used buffers did not induce detectable damage to the sugar-phosphate backbone of DNA. Replication of Cr(VI)-modified plasmids in intact human fibroblasts has shown that cysteine-dependent metabolism of Cr(VI) resulted in the formation of mutagenic and replication-blocking DNA lesions. Selective elimination of Cr-DNA adducts from Cr(VI)-treated plasmids abolished all genotoxic responses, indicating that nonoxidative, Cr(III)-dependent reactions were responsible for the induction of both mutagenicity and replication blockage by Cr(VI). The demonstration of the mutagenic potential of Cr-DNA adducts suggests that these lesions can be explored in the development of specific and mechanistically important biomarkers of exposure to toxic forms of Cr.

  7. Enantioselective recognition of mono-demethylated methoxychlor metabolites by the estrogen receptor.

    Science.gov (United States)

    Miyashita, Masahiro; Shimada, Takahiro; Nakagami, Shizuka; Kurihara, Norio; Miyagawa, Hisashi; Akamatsu, Miki

    2004-02-01

    Metabolites of methoxychlor such as 2-(p-hydroxyphenyl)-2-(p-methoxyphenyl)-1,1,1-trichloroethane (mono-OH-MXC) and 2,2-bis(p-hydroxyphenyl)-1,1,1-trichloroethane (bis-OH-MXC), have estrogenic activity. Mono-OH-MXC is a chiral compound in which the carbon atom bridging two benzene rings is the chiral centre. In previous studies the estrogenic activity of racemic mono-OH-MXC has been measured, and the activity of each enantiomer of this compound has not yet been elucidated. In this study, we evaluated the estrogen receptor-binding activity of each enantiomer of mono-OH-MXC to clarify the enantioselective recognition by the estrogen receptor. (S)-mono-OH-MXC showed 3-fold higher binding activity than that of the (R) enantiomer. The activity of bis-OH-MXC was only 1.7-fold higher than that of (S)-mono-OH-MXC. This result suggests that the one hydroxy group and the orientation of the CCl3 group of mono- and bis-OH-MXCs are important for the interaction with the estrogen receptor. The result also points out the estrogenic activity of methoxychlor after metabolic activation in vivo, which predominantly produces the (S)-mono-OH-MXC, may be higher than estimated from the in vitro activity of racemic mixtures.

  8. Paroxetine, a cytochrome P450 2D6 inhibitor, diminishes the stereoselective O-demethylation and reduces the hypoalgesic effect of tramadol

    DEFF Research Database (Denmark)

    Laugesen, S; Enggaard, T P; Pedersen, R S

    2005-01-01

    OBJECTIVE: Tramadol hydrochloride (INN, tramadol) exerts its antinociceptive action through a monoaminergic effect mediated by the parent compound and an opioid effect mediated mainly by the O-demethylated metabolite (+)-M1. O-demethylation is catalyzed by cytochrome P450 (CYP) 2D6. Paroxetine...... is a very potent inhibitor of CYP2D6. The objective of this study was to investigate the influence of paroxetine pretreatment on the biotransformation and the hypoalgesic effect of tramadol. METHODS: With and without paroxetine pretreatment (20 mg daily for 3 consecutive days), the formation of M1...... and the analgesic effect of 150 mg of tramadol were studied in 16 healthy extensive metabolizers of sparteine in a randomized, double-blind, placebo-controlled, 4-way crossover study by use of experimental pain models. RESULTS: With paroxetine pretreatment, the area under the plasma concentration-time curve (AUC...

  9. Paroxetine, a cytochrome P450 2D6 inhibitor, diminishes the stereoselective O-demethylation and reduces the hypoalgesic effect of tramadol

    DEFF Research Database (Denmark)

    Laugesen, S; Enggaard, T P; Pedersen, R S;

    2005-01-01

    OBJECTIVE: Tramadol hydrochloride (INN, tramadol) exerts its antinociceptive action through a monoaminergic effect mediated by the parent compound and an opioid effect mediated mainly by the O-demethylated metabolite (+)-M1. O-demethylation is catalyzed by cytochrome P450 (CYP) 2D6. Paroxetine...... is a very potent inhibitor of CYP2D6. The objective of this study was to investigate the influence of paroxetine pretreatment on the biotransformation and the hypoalgesic effect of tramadol. METHODS: With and without paroxetine pretreatment (20 mg daily for 3 consecutive days), the formation of M1...... and the analgesic effect of 150 mg of tramadol were studied in 16 healthy extensive metabolizers of sparteine in a randomized, double-blind, placebo-controlled, 4-way crossover study by use of experimental pain models. RESULTS: With paroxetine pretreatment, the area under the plasma concentration-time curve (AUC...

  10. Resolution, configurational assignment, and enantiopharmacology at glutamate receptors of 2-amino-3-(3-carboxy-5-methyl-4-isoxazolyl)propionic acid (ACPA) and demethyl-ACPA

    DEFF Research Database (Denmark)

    Johansen, T N; Stensbøl, T B; Nielsen, B;

    2001-01-01

    We have previously described (RS)-2-amino-3-(3-carboxy-5-methyl-4-isoxazolyl)propionic acid (ACPA) as a potent agonist at the (RS)-2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid (AMPA) receptor subtype of (S)-glutamic acid (Glu) receptors. We now report the chromatographic resolution...... of ACPA and (RS)-2-amino-3-(3-carboxy-4-isoxazolyl)propionic acid (demethyl-ACPA) using a Sumichiral OA-5000 column. The configuration of the enantiomers of both compounds have been assigned based on X-ray crystallographic analyses, supported by circular dichroism spectra and elution orders on chiral HPLC...... columns. Furthermore, the enantiopharmacology of ACPA and demethyl-ACPA was investigated using radioligand binding and cortical wedge electrophysiological assay systems and cloned metabotropic Glu receptors. (S)-ACPA showed high affinity in AMPA binding (IC(50) = 0.025 microM), low affinity in kainic acid...

  11. Epigenetic Changes during Hepatic Stellate Cell Activation.

    Directory of Open Access Journals (Sweden)

    Silke Götze

    Full Text Available Hepatic stellate cells (HSC, which can participate in liver regeneration and fibrogenesis, have recently been identified as liver-resident mesenchymal stem cells. During their activation HSC adopt a myofibroblast-like phenotype accompanied by profound changes in the gene expression profile. DNA methylation changes at single genes have been reported during HSC activation and may participate in the regulation of this process, but comprehensive DNA methylation analyses are still missing. The aim of the present study was to elucidate the role of DNA methylation during in vitro activation of HSC.The analysis of DNA methylation changes by antibody-based assays revealed a strong decrease in the global DNA methylation level during culture-induced activation of HSC. To identify genes which may be regulated by DNA methylation, we performed a genome-wide Methyl-MiniSeq EpiQuest sequencing comparing quiescent and early culture-activated HSC. Approximately 400 differentially methylated regions with a methylation change of at least 20% were identified, showing either hypo- or hypermethylation during activation. Further analysis of selected genes for DNA methylation and expression were performed revealing a good correlation between DNA methylation changes and gene expression. Furthermore, global DNA demethylation during HSC activation was investigated by 5-bromo-2-deoxyuridine assay and L-mimosine treatment showing that demethylation was independent of DNA synthesis and thereby excluding a passive DNA demethylation mechanism.In summary, in vitro activation of HSC initiated strong DNA methylation changes, which were associated with gene regulation. These results indicate that epigenetic mechanisms are important for the control of early HSC activation. Furthermore, the data show that global DNA demethylation during activation is based on an active DNA demethylation mechanism.

  12. Overexpression of ShCYP51B and ShatrD in Sclerotinia homoeocarpa Isolates Exhibiting Practical Field Resistance to a Demethylation Inhibitor Fungicide

    OpenAIRE

    Hulvey, Jon; Popko, James T.; Sang, Hyunkyu; Berg, Andrew; Jung, Geunhwa

    2012-01-01

    We investigated genetic factors that govern the reduced propiconazole sensitivity of Sclerotinia homoeocarpa field isolates collected during a 2-year field efficacy study on dollar spot disease of turf in five New England sites. These isolates displayed a >50-fold range of in vitro sensitivity to a sterol demethylation inhibitor (DMI) fungicide, propiconazole, making them ideal for investigations of genetic mechanisms of reduced DMI sensitivity. The CYP51 gene homolog in S. homoeocarpa (ShCYP...

  13. Mercury methylation and demethylation by periphyton biofilms and their host in a fluvial wetland of the St. Lawrence River (QC, Canada)

    Energy Technology Data Exchange (ETDEWEB)

    Hamelin, Stéphanie; Planas, Dolors [GRIL, Département de sciences biologiques, Université du Québec à Montréal, C.P. 8888, Succursale Centre-Ville, Montreal, Quebec H3C 3P8 (Canada); Amyot, Marc [GRIL, Département de sciences biologiques, Université de Montréal, C.P. 6128, Succursale Centre-Ville, Montréal, Quebec H3C 3J7 (Canada)

    2015-04-15

    Wetlands in large rivers are important sites of production of the neurotoxin methylmercury (MeHg), and the periphyton growing on wetland macrophytes are increasingly recognized as key players in this production and transfer in food webs. Information is lacking about mercury methylation (K{sub m}) and demethylation (K{sub d}) rates in periphytic biofilms from the Northern Hemisphere, as well as about the drivers of net MeHg production, hampering ecosystem modeling of Hg cycling. Mercury methylation and demethylation rates were measured in periphytic biofilms growing on submerged plants in a shallow fluvial lake located in a temperate cold region (St. Lawrence River, Quebec, Canada). Incubations were performed in situ within macrophyte beds using low-level spikes of {sup 199}HgO and Me{sup 200}Hg stable isotopes as tracers. A direct relationship was observed between K{sub m} (0.002 to 0.137 d{sup −1}) and [MeHg] in periphyton. A similar relationship was found between K{sub d} (0.096 to 0.334 d{sup −1}) and [inorganic Hg]. Periphyton of Lake St. Pierre reached high levels of net MeHg production that were two orders of magnitude higher than those found in local sediment. This production varied through the plant growing season and was mainly driven by environmental variables such as depth of growth, available light, dissolved oxygen, temperature, plant community structure, and productivity of the habitat. - Highlights: • Periphyton Hg methylation and demethylation were studied in a large fluvial lake. • Addition of stable Hg isotopes was used to obtain in situ rates for these processes. • Net methylation was higher in periphyton than in local sediments. • Methylation and demethylation rates fluctuated during the summer. • Key drivers of rates were depth, light, temperature, and community structure.

  14. Quantification of citalopram or escitalopram and their demethylated metabolites in neonatal hair samples by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Frison, Giampietro; Favretto, Donata; Vogliardi, Susanna; Terranova, Claudio; Ferrara, Santo Davide

    2008-08-01

    Citalopram and escitalopram are highly selective serotonin reuptake inhibitors widely used in the treatment of depression. They exhibit adverse drug reactions and side effects, however, and the development of specific methods for their determination is of great interest in clinical and forensic toxicology. A liquid chromatography-tandem mass spectrometry method has been developed and validated for the assay of citalopram, escitalopram, and their demethylated metabolites in 10-mg hair samples. The analytes were extracted by incubation in methanol and liquid/liquid extraction with diethyl ether/dichloromethane. Gradient elution on a narrow bore C18 column was realized using clomipramine-d3 as an internal standard. Positive ion electrospray ionization and tandem mass spectrometry determination by collision-induced dissociation were performed in an ion trap mass spectrometer. The method exhibited a linear range of 25 to 2000 pg/mg, a quantification limit of 25 pg/mg for all analytes, relative standard deviations in the range of 12.10 to 9.80 (intraassay), and 13.80 to 11.78 (interassay), and accuracies (as percent recovery of the spiked standards) in the range of 90% to 110%; it was applied to the determination of citalopram and escitalopram and their metabolites in hair samples of two newborns to document their in utero exposure to the drugs. The method proved suitable for neonatal hair analysis of citalopram or escitalopram and was applied to two real cases of gestational exposure.

  15. Deferasirox and vitamin D improves overall survival in elderly patients with acute myeloid leukemia after demethylating agents failure.

    Directory of Open Access Journals (Sweden)

    Etienne Paubelle

    Full Text Available The prognosis of acute myeloid leukemia (AML in elderly (≥65 years patients is poor and treatment remains non-consensual especially for those who are not eligible for intensive therapies. Our group has shown that in vitro the iron chelator deferasirox (DFX synergizes with vitamin D (VD to promote monocyte differentiation in primary AML cells. Herein, we present results from a retrospective case-control study in which the association of DFX (1-2 g/d and 25-hydroxycholecalciferol (100,000 IU/week (DFX/VD was proposed to patients following demethylating agents failure. Median survival of patients treated with DFX/VD combination (n = 17 was significantly increased in comparison with matched patients receiving best supportive care (BSC alone (n = 13 (10.4 versus 4 months respectively. In addition, the only factor associated to an increased overall survival in DFX/VD-treated patients was serum VD levels. We conclude that DFX/VD treatment correlated with increased overall survival of AML patients in this retrospective cohort of elderly patients.

  16. Deferasirox and Vitamin D Improves Overall Survival in Elderly Patients with Acute Myeloid Leukemia after Demethylating Agents Failure

    Science.gov (United States)

    Suarez, Felipe; Callens, Céline; Dussiot, Michaël; Isnard, Françoise; Rubio, Marie-Thérèse; Damaj, Gandhi; Gorin, Norbert-Claude; Marolleau, Jean-Pierre; Monteiro, Renato C.; Moura, Ivan C.; Hermine, Olivier

    2013-01-01

    The prognosis of acute myeloid leukemia (AML) in elderly (≥65 years) patients is poor and treatment remains non-consensual especially for those who are not eligible for intensive therapies. Our group has shown that in vitro the iron chelator deferasirox (DFX) synergizes with vitamin D (VD) to promote monocyte differentiation in primary AML cells. Herein, we present results from a retrospective case-control study in which the association of DFX (1–2 g/d) and 25-hydroxycholecalciferol (100,000 IU/week) (DFX/VD) was proposed to patients following demethylating agents failure. Median survival of patients treated with DFX/VD combination (n = 17) was significantly increased in comparison with matched patients receiving best supportive care (BSC) alone (n = 13) (10.4 versus 4 months respectively). In addition, the only factor associated to an increased overall survival in DFX/VD-treated patients was serum VD levels. We conclude that DFX/VD treatment correlated with increased overall survival of AML patients in this retrospective cohort of elderly patients. PMID:23840388

  17. Intramolecular Oxidative O-Demethylation of an Oxoferryl Porphyrin Complexed with a Per-O-methylated β-Cyclodextrin Dimer.

    Science.gov (United States)

    Kitagishi, Hiroaki; Kurosawa, Shun; Kano, Koji

    2016-11-22

    The intramolecular oxidation of ROCH3 to ROCH2 OH, where the latter compound spontaneously decomposed to ROH and HCHO, was observed during the reaction of the supramolecular complex (met-hemoCD3) with cumene hydroperoxide in aqueous solution. Met-hemoCD3 is composed of meso-tetrakis(4-sulfonatophenyl)porphinatoiron(III) (Fe(III) TPPS) and a per-O-methylated β-cyclodextrin dimer having an -OCH2 PyCH2 O- linker (Py=pyridine-3,5-diyl). The O=Fe(IV) TPPS complex was formed by the reaction of met-hemoCD3 with cumene hydroperoxide, and isolated by gel-filtration chromatography. Although the isolated O=Fe(IV) TPPS complex in the cyclodextrin cage was stable in aqueous solution at 25 °C, it was gradually converted to Fe(II) TPPS (t1/2 =7.6 h). This conversion was accompanied by oxidative O-demethylation of an OCH3 group in the cyclodextrin dimer. The results indicated that hydrogen abstraction by O=Fe(IV) TPPS from ROCH3 yields HO-Fe(III) TPPS and ROCH2(.) . This was followed by radical coupling to afford Fe(II) TPPS and ROCH2 OH. The hemiacetal (ROCH2 OH) immediately decomposed to ROH and HCHO. This study revealed the ability of oxoferryl porphyrin to induce two-electron oxidation.

  18. Damage-inducible intragenic demethylation of the human TP53 tumor suppressor gene is associated with transcription from an alternative intronic promoter.

    Science.gov (United States)

    Blackburn, James; Roden, Daniel L; Ng, Robert; Wu, Jianmin; Bosman, Alexis; Epstein, Richard J

    2016-12-01

    Wild-type TP53 exons 5-8 contain CpG dinucleotides that are prone to methylation-dependent mutation during carcinogenesis, but the regulatory effects of methylation affecting these CpG sites are unclear. To clarify this, we first assessed site-specific TP53 CpG methylation in normal and transformed cells. Both DNA damage and cell ageing were associated with site-specific CpG demethylation in exon 5 accompanied by induction of a truncated TP53 isoform regulated by an adjacent intronic promoter (P2). We then synthesized novel synonymous TP53 alleles with divergent CpG content but stable encodement of the wild-type polypeptide. Expression of CpG-enriched TP53 constructs selectively reduced production of the full-length transcript (P1), consistent with a causal relationship between intragenic demethylation and transcription. 450K methylation comparison of normal (TP53-wildtype) and cancerous (TP53-mutant) human cells and tissues revealed focal cancer-associated declines in CpG methylation near the P1 transcription start site, accompanied by rises near the alternate exon 5 start site. These data confirm that site-specific changes of intragenic TP53 CpG methylation are extrinsically inducible, and suggest that human cancer progression is mediated in part by dysregulation of damage-inducible intragenic CpG demethylation that alters TP53 P1/P2 isoform expression. © 2015 The Authors. Molecular Carcinogenesis Published by Wiley Periodicals, Inc.

  19. Induction of Cyclooxygenase-2 Expression by Hepatitis B Virus Depends on Demethylation-associated Recruitment of Transcription Factors to the Promoter

    Directory of Open Access Journals (Sweden)

    Wu Jianguo

    2011-03-01

    Full Text Available Abstract Background The hepatitis B virus (HBV is a major etiological factor of inflammation and damage to the liver resulting in hepatocellular carcinoma. Transcription factors play important roles in the disordered gene expression and liver injury caused by HBV. However, the molecular mechanisms behind this observation have not been defined. Results In this study, we observed that circulating prostaglandin (PGE 2 synthesis was increased in patients with chronic hepatitis B infection, and detected elevated cyclooxygenase (COX-2 expression in HBV- and HBx-expressing liver cells. Likewise, the association of HBx with C/EBPβ contributed to the induction of COX-2. The COX-2 promoter was hypomethylated in HBV-positive cells, and specific demethylation of CpG dinucleotides within each of the two NF-AT sites in the COX-2 promoter resulted in the increased binding affinity of NF-AT to the cognate sites in the promoter, followed by increased COX-2 expression and PGE2 accumulation. The DNA methylatransferase DNMT3B played a key role in the methylation of the COX-2 promoter, and its decreased binding to the promoter was responsible for the regional demethylation of CpG sites, and for the increased binding of transcription factors in HBV-positive cells. Conclusion Our results indicate that upregulation of COX-2 by HBV and HBx is mediated by both demethylation events and recruitment of multiple transcription factors binding to the promoter.

  20. Epigenetic regulations in the IFNγ signalling pathway: IFNγ-mediated MHC class I upregulation on tumour cells is associated with DNA demethylation of antigen-presenting machinery genes.

    Science.gov (United States)

    Vlková, Veronika; Štěpánek, Ivan; Hrušková, Veronika; Šenigl, Filip; Mayerová, Veronika; Šrámek, Martin; Šímová, Jana; Bieblová, Jana; Indrová, Marie; Hejhal, Tomáš; Dérian, Nicolas; Klatzmann, David; Six, Adrien; Reiniš, Milan

    2014-08-30

    Downregulation of MHC class I expression on tumour cells, a common mechanism by which tumour cells can escape from specific immune responses, can be associated with coordinated silencing of antigen-presenting machinery genes. The expression of these genes can be restored by IFNγ. In this study we documented association of DNA demethylation of selected antigen-presenting machinery genes located in the MHC genomic locus (TAP-1, TAP-2, LMP-2, LMP-7) upon IFNγ treatment with MHC class I upregulation on tumour cells in several MHC class I-deficient murine tumour cell lines (TC-1/A9, TRAMP-C2, MK16 and MC15). Our data also documented higher methylation levels in these genes in TC-1/A9 cells, as compared to their parental MHC class I-positive TC-1 cells. IFNγ-mediated DNA demethylation was relatively fast in comparison with demethylation induced by DNA methyltransferase inhibitor 5-azacytidine, and associated with increased histone H3 acetylation in the promoter regions of APM genes. Comparative transcriptome analysis in distinct MHC class I-deficient cell lines upon their treatment with either IFNγ or epigenetic agents revealed that a set of genes, significantly enriched for the antigen presentation pathway, was regulated in the same manner. Our data demonstrate that IFNγ acts as an epigenetic modifier when upregulating the expression of antigen-presenting machinery genes.

  1. Influence of Decitabine on Demethylation of P15INK4B Gene and the Growth and Apoptosis of Burkitt Lymphoma Raji Cells

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    LIU Qiao

    2014-12-01

    Full Text Available Objective: To explore the methylation status of P15INK4B gene and the biochemical influence of decitabine on the demethylation of P15INK4B gene and the growth and apoptosis of Burkitt lymphoma Raji cells. Methods: Trypan blue was used to test the effects of different concentrations of decitabine on cell growth curve of Burkitt lymphoma Rajj cells. Cell apoptostic rate was detected by flow cytometry (FCM. The expression of P15INK4B gene was detected by reverse transcription-polymerase chain reaction (RT-PCR and the degree of methylation of P15INK4B gene by methylation-specific PCR (MSP. Results: Different concentrations of decitabine had an inhibiting effect on the proliferation of Raji cells, and promote the apoptosis of Raji cells. After 48-h treatment of decitabine, the mRNA expression of P15INK4B gene of Raji cells was up-regulated in a dose-dependent manner by inducing the demethylation of P15INK4B gene. . Conclusion: There exists hypermethylated P15INK4B gene in Burkitt lymphoma Raji cells which makes P15INK4B gene down-regulated. However, decitabine can up-regulate the mRNA expression of P15INK4B gene through inducing the demethylation of P15INK4B gene, thus inhibiting the proliferation of lymphoma Raji cells.

  2. DEMETER DNA glycosylase establishes MEDEA polycomb gene self-imprinting by allele-specific demethylation.

    Science.gov (United States)

    Gehring, Mary; Huh, Jin Hoe; Hsieh, Tzung-Fu; Penterman, Jon; Choi, Yeonhee; Harada, John J; Goldberg, Robert B; Fischer, Robert L

    2006-02-10

    MEDEA (MEA) is an Arabidopsis Polycomb group gene that is imprinted in the endosperm. The maternal allele is expressed and the paternal allele is silent. MEA is controlled by DEMETER (DME), a DNA glycosylase required to activate MEA expression, and METHYLTRANSFERASE I (MET1), which maintains CG methylation at the MEA locus. Here we show that DME is responsible for endosperm maternal-allele-specific hypomethylation at the MEA gene. DME can excise 5-methylcytosine in vitro and when expressed in E. coli. Abasic sites opposite 5-methylcytosine inhibit DME activity and might prevent DME from generating double-stranded DNA breaks. Unexpectedly, paternal-allele silencing is not controlled by DNA methylation. Rather, Polycomb group proteins that are expressed from the maternal genome, including MEA, control paternal MEA silencing. Thus, DME establishes MEA imprinting by removing 5-methylcytosine to activate the maternal allele. MEA imprinting is subsequently maintained in the endosperm by maternal MEA silencing the paternal allele.

  3. Evidence that active demethylation mechanisms maintain the genome of carcinoma in situ cells hypomethylated in the adult testis

    DEFF Research Database (Denmark)

    Kristensen, D G; Nielsen, J E; Jørgensen, Anne;

    2014-01-01

    cells were assessed by quantitative measurements. The expression of TET1, TET2, APOBEC1, MBD4, APEX1, PARP1, DNMT1, DNMT3A, DNMT3B and DNMT3L in adult testis specimens with CIS and in human fetal testis was investigated by immunohistochemistry and immunofluorescence.Results:DNA from micro-dissected CIS...

  4. TAp63γ demethylation regulates protein stability and cellular distribution during neural stem cell differentiation.

    Directory of Open Access Journals (Sweden)

    Maria B Fonseca

    Full Text Available p63 is a close relative of the p53 tumor suppressor and transcription factor that modulates cell fate. The full-length isoform of p63, containing a transactivation (TA domain (TAp63 is an essential proapoptotic protein in neural development. The role of p63 in epithelial development is also well established; however, its precise function during neural differentiation remains largely controversial. Recently, it has been demonstrated that several conserved elements of apoptosis are also integral components of cellular differentiation; p53 directly interacts with key regulators of neurogenesis. The aim of this study was to evaluate the role of p63 during mouse neural stem cell (NSC differentiation and test whether the histone H3 lysine 27-specific demethylase JMJD3 interacts with p63 to redirect NSCs to neurogenesis. Our results showed that JMJD3 and TAp63γ are coordinately regulated to establish neural-specific gene expression programs in NSCs undergoing differentiation. JMJD3 overexpression increased TAp63γ levels in a demethylase activity-dependent manner. Importantly, overexpression of TAp63γ increased β-III tubulin whereas downregulation of TAp63γ by specific p63 siRNA decreased β-III tubulin. Immunoprecipitation assays demonstrated direct interaction between TAp63γ and JMJD3, and modulation of TAp63γ methylation status by JMJD3-demethylase activity. Importantly, the demethylase activity of JMJD3 influenced TAp63γ protein stabilization and cellular distribution, as well as TAp63γ-regulated neurogenesis. These findings clarify the role of p63 in adult neural progenitor cells and reveal TAp63γ as a direct target for JMJD3-mediated neuronal commitment.

  5. Timing of transcriptional quiescence during gametogenesis is controlled by global histone H3K4 demethylation.

    Science.gov (United States)

    Xu, Mengshu; Soloveychik, Maria; Ranger, Mathieu; Schertzberg, Michael; Shah, Zarna; Raisner, Ryan; Venkatasubrahmanyan, Shivkumar; Tsui, Kyle; Gebbia, Marinella; Hughes, Tim; van Bakel, Harm; Nislow, Corey; Madhani, Hiten D; Meneghini, Marc D

    2012-11-13

    Gametes are among the most highly specialized cells produced during development. Although gametogenesis culminates in transcriptional quiescence in plants and animals, regulatory mechanisms controlling this are unknown. Here, we confirm that gamete differentiation in the single-celled yeast Saccharomyces cerevisiae is accompanied by global transcriptional shutoff following the completion of meiosis. We show that Jhd2, a highly conserved JARID1-family histone H3K4 demethylase, activates protein-coding gene transcription in opposition to this programmed transcriptional shutoff, sustaining the period of productive transcription during spore differentiation. Moreover, using genome-wide nucleosome, H3K4me, and transcript mapping experiments, we demonstrate that JHD2 globally represses intergenic noncoding transcription during this period. The widespread transcriptional defects of JHD2 mutants are associated with precocious differentiation and the production of stress-sensitive spores, demonstrating that Jhd2 regulation of the global postmeiotic transcriptional program is critical for the production of healthy meiotic progeny.

  6. A dark and constitutively active mutant of the tiger salamander UV pigment.

    Science.gov (United States)

    Kono, Masahiro; Crouch, Rosalie K; Oprian, Daniel D

    2005-01-18

    A triple mutant (F86L/T93P/S118T; bovine rhodopsin numbering) of the tiger salamander UV cone pigment appears to be trapped in an open conformation that is metarhodopsin-II-like. The pigment is able to activate transducin in the dark, and the ligand-free apoprotein is also able to activate transducin constitutively. The pigment permits protons and chloride ions from solution access to the active site as it displays a pH- and NaCl-dependent absorption spectrum not observed with the wild-type pigment. However, the wild-type properties of light-dependent activity and a pH-independent absorption spectrum are recovered upon reconstitution of the triple mutant with 11-cis-9-demethyl retinal. These results suggest that binding the native chromophore cannot deactivate the protein because of steric interactions between the protein, possibly residue 118, and the 9-methyl group of the chromophore. Furthermore, the absorption spectrum of the 9-demethyl retinal regenerated pigment exhibits a band broader and with lower extinction at the absorption maximum than either the human blue or salamander UV wild-type pigments generated with the same retinal analogue. The broad spectrum appears to be comprised of two or more species and can be well-fit by a sum of scaled spectra of the two wild-type pigments. Binding the chromophore appears to trap the pigment in two or more conformations. The triple mutant reported here represents the first example of a dark-active cone pigment and constitutively active cone opsin.

  7. Electrophoretically mediated microanalysis for characterization of the enantioselective CYP3A4 catalyzed N-demethylation of ketamine.

    Science.gov (United States)

    Ying Kwan, Hiu; Thormann, Wolfgang

    2012-11-01

    Execution of an enzymatic reaction performed in a capillary with subsequent electrophoretic analysis of the formed products is referred to as electrophoretically mediated microanalysis (EMMA). An EMMA method was developed to investigate the stereoselectivity of the CYP3A4-mediated N-demethylation of ketamine. Ketamine was incubated in a 50 μm id bare fused-silica capillary together with human CYP3A4 Supersomes using a 100 mM phosphate buffer (pH 7.4) at 37°C. A plug containing racemic ketamine and the NADPH regenerating system including all required cofactors for the enzymatic reaction was injected, followed by a plug of the metabolizing enzyme CYP3A4 (500 nM). These two plugs were bracketed by plugs of incubation buffer to ensure proper conditions for the enzymatic reaction. The rest of the capillary was filled with a pH 2.5 running buffer comprising 50 mM Tris, phosphoric acid, and 2% w/v of highly sulfated γ-cyclodextrin. Mixing of reaction plugs was enhanced via application of -10 kV for 10 s. After an incubation of 8 min at 37°C without power application (zero-potential amplification), the capillary was cooled to 25°C within 3 min followed by application of -10 kV for the separation and detection of the formed enantiomers of norketamine. Norketamine formation rates were fitted to the Michaelis-Menten model and the elucidated values for V(max) and K(m) were found to be comparable to those obtained from the off-line assay of a previous study.

  8. Insights into the epigenetic mechanisms involving histone lysine methylation and demethylation in ischemia induced damage and repair has therapeutic implication.

    Science.gov (United States)

    Chakravarty, Sumana; Jhelum, Priya; Bhat, Unis Ahmad; Rajan, Wenson D; Maitra, Swati; Pathak, Salil S; Patel, Anant B; Kumar, Arvind

    2017-01-01

    Cerebral ischemic stroke is one of the leading causes of death and disability worldwide. Therapeutic interventions to minimize ischemia-induced neural damage are limited due to poor understanding of molecular mechanisms mediating complex pathophysiology in stroke. Recently, epigenetic mechanisms mostly histone lysine (K) acetylation and deacetylation have been implicated in ischemic brain damage and have expanded the dimensions of potential therapeutic intervention to the systemic/local administration of histone deacetylase inhibitors. However, the role of other epigenetic mechanisms such as histone lysine methylation and demethylation in stroke-induced damage and subsequent recovery process is elusive. Here, we established an Internal Carotid Artery Occlusion (ICAO) model in CD1 mouse that resulted in mild to moderate level of ischemic damage to the striatum, as suggested by magnetic resonance imaging (MRI), TUNEL and histopathological staining along with an evaluation of neurological deficit score (NDS), grip strength and rotarod performance. The molecular investigations show dysregulation of a number of histone lysine methylases (KMTs) and few of histone lysine demethylases (KDMs) post-ICAO with significant global attenuation in the transcriptionally repressive epigenetic mark H3K9me2 in the striatum. Administration of Dimethyloxalylglycine (DMOG), an inhibitor of KDM4 or JMJD2 class of histone lysine demethylases, significantly ameliorated stroke-induced NDS by restoring perturbed H3K9me2 levels in the ischemia-affected striatum. Overall, these results highlight the novel role of epigenetic regulatory mechanisms controlling the epigenetic mark H3K9me2 in mediating the stroke-induced striatal damage and subsequent repair following mild to moderate cerebral ischemia.

  9. Carbon-cycle effects of differences in soil moisture and soil extracellular enzyme activity at sites representing different land-use histories in high-elevation Ecuadorian páramo landscapes

    Science.gov (United States)

    McKnight, J.; Harden, C. P.; Schaeffer, S. M.

    2016-12-01

    Ecuadorian páramo grasslands are important regional soil carbon sinks. In the páramo of the Mazar Wildlife Reserve, differences in soil carbon content among different types of land use may reflect changes in soil carbon-acquisition related microbial enzyme activity after land cover and soil moisture are altered; however, this hypothesis has not been tested explicitly for Ecuadorian páramos. This study used a fluorescence enzyme assay to assess the activities of four different extracellular enzymes representing carbon acquisition: α-glucosidase, β-glucosidase, β-D-cellulobiohydrolase, and β-xylosidase in Andean páramo soils. Acquisition activities were also measured for nitrogen (N-acetyl-β-glucosidase and leucine aminopeptidase) and phosphorus (phosphatase) to assess stoichiometric differences between land-uses, which can affect soil microbial activity related to carbon acquisition. Soils were analyzed from four land uses: native forest, grass páramo, recently burned grass páramo, and non-native pine plantation. Carbon acquisition activity was highest at the pine site (678 nmol h-1 g-1) and lowest at the recently burned páramo site (252 nmol h-1 g-1), indicating the lowest and highest available soil carbon, respectively. Carbon-acquisition EE activity was significantly higher at the grass páramo site (595 nmol h-1 g-1) than at the recently burned páramo and native forest sites. At the grass páramo site, a history of burning as a management strategy and high carbon-acquisition EE activity could indicate the presence of pyrogenic soil organic matter, which is more resistant to microbial decomposition. Soils at the native forest and both grassland sites were phosphorus limited, and soil at the pine site had higher nitrogen-acquisition activity, indicative of a shift to nitrogen-limited soil stoichiometric conditions. To our knowledge these are the first data reported for soil extracellular enzyme activities for Ecuadorian páramos.

  10. Potential Mechanism of Action of 3′-Demethoxy-6-O-demethyl-isoguaiacin on Methicillin Resistant Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Juan Manuel J. Favela-Hernández

    2015-07-01

    Full Text Available Bacterial infections represent one of the main threats to global public health. One of the major causative agents associated with high morbidity and mortality infections in hospitals worldwide is methicillin-resistant Staphylococcus aureus. Therefore, there is a need to develop new antibacterial agents to treat these infections, and natural products are a rich source of them. In previous studies, we reported that lignan 3′-demethoxy-6-O-demethylisoguaiacin, isolated and characterized from Larrea tridentate, showed the best activity towards methicillin-resistant S. aureus. Thus, the aim of this study was to determine the potential molecular mechanism of the antibacterial activity of 3′-demethoxy-6-O-demethylisoguaiacin against methicillin-resistant S. aureus using microarray technology. Results of microarray genome expression were validated by real-time polymerase chain reaction (RT-PCR. The genetic profile expression results showed that lignan 3′-demethoxy-6-O-demethylisoguaiacin had activity on cell membrane affecting proteins of the ATP-binding cassette (ABC transport system causing bacteria death. This molecular mechanism is not present in any antibacterial commercial drug and could be a new target for the development of novel antibacterial agents.

  11. The accumulation of DNA demethylation in Sat α in normal gastric tissues with Helicobacter pylori infection renders susceptibility to gastric cancer in some individuals.

    Science.gov (United States)

    Saito, Masaaki; Suzuki, Koichi; Maeda, Takafumi; Kato, Takaharu; Kamiyama, Hidenori; Koizumi, Kei; Miyaki, Yuichiro; Okada, Shinichiro; Kiyozaki, Hirokazu; Konishi, Fumio

    2012-06-01

    Helicobacter pylori (HP) infection is widely recognized as a risk factor for gastric cancer, but only a minority of infected individuals develop gastric cancer. The aim of this study was to determine whether DNA demethylation in non-cancerous gastric mucosa (NGM) significantly enhances susceptibility to gastric cancer. A total of 165 healthy volunteers, including 83 HP-positive and 82-negative individuals, as well as 83 patients with single and 18 with synchronous double gastric cancer (GC) were enrolled in this study. The relative demethylation levels (RDLs) of repetitive sequences, including Alu, LINE-1 and Sat α, were quantified by real-time methylation-specific polymerase chain reaction. The Alu RDL did not exhibit any differences within each respective group, whereas LINE-1 RDL was significantly elevated in cancer tissues compared with the NGM in the other groups (PSat α RDL correlated with HP infection and cancer development. Sat α RDL was significantly elevated in the NGM in HP-positive compared with HP-negative (PSat α RDL of the NGM in the total population increased in an age-dependent manner, it was significantly increased in a fraction of younger GC patients (Sat α RDL in the NGM compared with single GC (P=0.0014). In these two fractions, Sat α RDL in the NGM exhibited an inverse correlation with age. In conclusion, the present study demonstrated that the accumulation of DNA demethylation in Sat α RDL in the NGM with HP infection potentially renders susceptibility to gastric cancer in a fraction of GC patients younger than 45 years or in patients with multiple cancers.

  12. Modulation by decitabine of gene expression and growth of osteosarcoma U2OS cells in vitro and in xenografts: Identification of apoptotic genes as targets for demethylation

    Directory of Open Access Journals (Sweden)

    Xue Hui

    2007-09-01

    Full Text Available Abstract Background Methylation-mediated silencing of genes is one epigenetic mechanism implicated in cancer. Studies regarding the role of modulation of gene expression utilizing inhibitors of DNA methylation, such as decitabine, in osteosarcoma (OS have been limited. A biological understanding of the overall effects of decitabine in OS is important because this particular agent is currently undergoing clinical trials. The objective of this study was to measure the response of the OS cell line, U2OS, to decitabine treatment both in vitro and in vivo. Results Microarray expression profiling was used to distinguish decitabine-dependent changes in gene expression in U2OS cells, and to identify responsive loci with demethylated CpG promoter regions. U2OS xenografts were established under the sub-renal capsule of immune-deficient mice to study the effect of decitabine in vivo on tumor growth and differentiation. Reduced nuclear methylation levels could be detected in xenografts derived from treated mice by immunohistochemistry utilizing a 5-methylcytidine antibody. Decitabine treatment reduced tumor xenograft size significantly (p in vitro (p GADD45A, HSPA9B, PAWR, PDCD5, NFKBIA, and TNFAIP3 were also induced to ≥2-fold in vivo. Quantitative methylation pyrosequencing confirmed that the tested pro-apoptotic genes had CpG-island DNA demethylationas a result of U2OS decitabine treatment both in vitro and in xenografts Conclusion These data provide new insights regarding the use of epigenetic modifiers in OS, and have important implications for therapeutic trials involving demethylation drugs. Collectively, these data have provided biological evidence that one mode of action of decitabine may be the induction of apoptosis utilizing promoter-CpG demethylation of specific effectors in cell death pathways in OS.

  13. The applicability of activities in kinetic expressions : A more fundamental approach to represent the kinetics of the systemCO2–OH−–salt in terms of activities

    NARCIS (Netherlands)

    Haubrock, J.; Hogendoorn, J.A.; Versteeg, G.F.

    2007-01-01

    The applicability of utilizing activities instead of concentrations in kinetic expressions has been investigated using the reaction of CO2 in sodium hydroxide solutions also containing different neutral salts (LiCl, KCl and NaCl) as model system. For hydroxide systems it is known that when the react

  14. The N-demethylation of imipramine correlates with the oxidation of S-mephenytoin (S/R-ratio). A population study.

    OpenAIRE

    Skjelbo, E; Gram, L F; Brøsen, K

    1993-01-01

    The metabolism of imipramine was investigated in 106 healthy volunteers, all having a sparteine metabolic ratio (MR) of 0.2-0.5 and hence classified as extensive metabolisers. Each subject was given a single oral dose of 25 mg imipramine hydrochloride and blood for assays of imipramine and metabolites was collected 3 h thereafter. The desipramine/imipramine ratio and the 2-OH-desipramine/2-OH-imipramine ratio in plasma, reflecting the demethylation of imipramine and 2-OH-imipramine, respectiv...

  15. Orchard factors associated with resistance and cross resistance to sterol demethylation inhibitor fungicides in populations of Venturia inaequalis from Pennsylvania.

    Science.gov (United States)

    Pfeufer, Emily E; Ngugi, Henry K

    2012-03-01

    Orchard management practices, such as destroying of overwintered inoculum and limiting the number of fungicide applications, are often recommended as tactics for slowing the development of resistance to sterol demethylation-inhibitor (DMI) fungicides in populations of Venturia inaequalis. However, there is little quantitative evidence relating the use of such practices to levels of resistance in orchards. The aim of this study was to evaluate the sensitivity of V. inaequalis isolates from Pennsylvania to DMI fungicides, and to identify orchard management factors related to the incidence of resistant isolates. In total, 644 single-spore V. inaequalis cultures obtained from 20 apple orchards in 2008 or 2009 were tested for sensitivity to myclobutanil, fenbuconazole, or difenoconazole. Growers provided management history of the sampled plots. Widespread shifts toward resistance to the three fungicides were noted, with mean effective concentration for 50% inhibition (EC(50)) values of 2.136, 0.786, and 0.187 μg/ml for myclobutanil, fenbuconazole, and difenoconazole, respectively. Cross resistance to the three fungicides was documented in high correlation (Spearman's r > 0.6) between mean EC(50) values for 14 orchards. Based on a 0.5-μg/ml threshold, 66 and 26% of isolates were resistant to myclobutanil and fenbuconazole, respectively, and 22% were cross resistant to the two fungicides. A significant between-year shift toward increased resistance was noted in two of three orchards surveyed in both years. Failure to use dormant copper sprays, older trees, larger orchards, orchards with ≤10 cultivars, and application of >4 DMI sprays were positively correlated (0.0001 resistant isolates. Isolates from orchards with >4 DMI sprays were four times as likely to be resistant to fenbuconazole (odds ratio = 4.57; P = 0.015). Isolates from orchards without dormant copper sprays were twice as likely to be cross-shifted toward resistance to all three fungicides (odds ratio = 1

  16. Growth-inducing effects of argon plasma on soybean sprouts via the regulation of demethylation levels of energy metabolism-related genes

    Science.gov (United States)

    Zhang, Jiao Jiao; Jo, Jin Oh; Huynh, Do Luong; Mongre, Raj Kumar; Ghosh, Mrinmoy; Singh, Amit Kumar; Lee, Sang Baek; Mok, Young Sun; Hyuk, Park; Jeong, Dong Kee

    2017-02-01

    This study was conducted to determine the effects of argon plasma on the growth of soybean [Glycine max (L.) Merr.] sprouts and investigate the regulation mechanism of energy metabolism. The germination and growth characteristics were modified by argon plasma at different potentials and exposure durations. Upon investigation, plasma treatment at 22.1 kV for 12 s maximized the germination and seedling growth of soybean, increasing the concentrations of soluble protein, antioxidant enzymes, and adenosine triphosphate (ATP) as well as up-regulating ATP a1, ATP a2, ATP b1, ATP b2, ATP b3, target of rapamycin (TOR), growth-regulating factor (GRF) 1-6, down-regulating ATP MI25 mRNA expression, and increasing the demethylation levels of the sequenced region of ATP a1, ATP b1, TOR, GRF 5, and GRF 6 of 6-day-old soybean sprouts. These observations indicate that argon plasma promotes soybean seed germination and sprout growth by regulating the demethylation levels of ATP, TOR, and GRF.

  17. Analysis of the machinery and intermediates of the 5hmC-mediated DNA demethylation pathway in aging on samples from the MARK-AGE Study

    Science.gov (United States)

    Valentini, Elisabetta; Zampieri, Michele; Malavolta, Marco; Bacalini, Maria Giulia; Calabrese, Roberta; Guastafierro, Tiziana; Reale, Anna; Franceschi, Claudio; Hervonen, Antti; Koller, Bernhard; Bernhardt, Jürgen; Slagboom, P. Eline; Toussaint, Olivier; Sikora, Ewa; Gonos, Efstathios S.; Breusing, Nicolle; Grune, Tilman; Jansen, Eugène; Dollé, Martijn E.T.; Moreno-Villanueva, María; Sindlinger, Thilo; Bürkle, Alexander; Ciccarone, Fabio; Caiafa, Paola

    2016-01-01

    Gradual changes in the DNA methylation landscape occur throughout aging virtually in all human tissues. A widespread reduction of 5-methylcytosine (5mC), associated with highly reproducible site-specific hypermethylation, characterizes the genome in aging. Therefore, an equilibrium seems to exist between general and directional deregulating events concerning DNA methylation controllers, which may underpin the age-related epigenetic changes. In this context, 5mC-hydroxylases (TET enzymes) are new potential players. In fact, TETs catalyze the stepwise oxidation of 5mC to 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC) and 5-carboxylcytosine (5caC), driving the DNA demethylation process based on thymine DNA glycosylase (TDG)-mediated DNA repair pathway. The present paper reports the expression of DNA hydroxymethylation components, the levels of 5hmC and of its derivatives in peripheral blood mononuclear cells of age-stratified donors recruited in several European countries in the context of the EU Project ‘MARK-AGE’. The results provide evidence for an age-related decline of TET1, TET3 and TDG gene expression along with a decrease of 5hmC and an accumulation of 5caC. These associations were independent of confounding variables, including recruitment center, gender and leukocyte composition. The observed impairment of 5hmC-mediated DNA demethylation pathway in blood cells may lead to aberrant transcriptional programs in the elderly. PMID:27587280

  18. Demethylation of Cancer/Testis Antigens and CpG ODN Stimulation Enhance Dendritic Cell and Cytotoxic T Lymphocyte Function in a Mouse Mammary Model

    Directory of Open Access Journals (Sweden)

    Jun-Zhong Sun

    2013-01-01

    Full Text Available Background. Cancer/testis antigens (CTAs are ideal targets for cancer immunotherapy in virtue of their restricted expression profile in normal tissues. However, CTA-targeted immunotherapy has been rather disappointing clinical setting for CTAs are downregulated by cytosine-phosphate-guanosine (CpG methylation in their promoter regions, so that tumor cells have low immunogenicity. Methods. We reinduced mouse CTA P1A through demethylation process and generated P1A-specific cytotoxic lymphocytes (CTLs by immunizing BALB/c (H-2d mice with dendritic cells pulsed with a P1A-specific peptide and CpG oligodeoxynucleotide (ODN immune adjuvant. Results. We found that demethylation and CpG ODN immune adjuvant stimulation facilitated DC maturation and enhanced the allogenic capacity of P1A-specific CTLs against target cells both in vitro and in vivo. Conclusions. Our results suggested that CTA induction and immune adjuvant stimulation is a feasible strategy in cancer immunotherapy.

  19. Induction of a specific CD8+ T-cell response to cancer/testis antigens by demethylating pre-treatment against osteosarcoma.

    Science.gov (United States)

    Li, Binghao; Zhu, Xiaobing; Sun, Lingling; Yuan, Li; Zhang, Jian; Li, Hengyuan; Ye, Zhaoming

    2014-11-15

    Conventional non-surgical therapeutic regimens against osteosarcoma are subject to chemoresistance and tumor relapse, and immunotherapy may be promising for this tumor. However, it's hard to find satisfactory epitopes for immunotherapy against osteosarcoma. Cancer/testis antigens (CTAs), such as MAGE-A family and NY-ESO-1, the potential antigens that almost exclusively express in tumor cells and immune-privileged sites, have been found expressed in osteosarcoma also. Nevertheless, the expression of CTAs is downregulated in many tumors, constraining the application of immunotherapy. In this article, we demonstrate that the expression of MAGE-A family and NY-ESO-1 in osteosarcoma cells can be upregulated following treatment with demethylating agent 5-aza-2'-deoxycytidine and consequently induces a CTA specific CD8+ T-cell response against osteosarcoma in vitro and in vivo. The in vivo imaging was realized by using luciferase-transfected HOS cells and DiR labeled T-cells in severely combined immunodeficiency mouse models. Cytotoxic T cells specifically recognizing MAGE-A family and NY-ESO-1 clustered at the tumor site in mice pre-treated with DAC and resulted in tumor growth suppression, while it was not observed in mice without DAC pre-treatment. This study is important for more targeted therapeutic approaches and suggests that adoptive immunotherapy, combined with demethylating treatment, has the potential for non-surgical therapeutic strategy against osteosarcoma.

  20. Decitabine-Induced Demethylation of 5′ CpG Island in GADD45A Leads to Apoptosis in Osteosarcoma Cells1

    Science.gov (United States)

    Al-Romaih, Khaldoun; Sadikovic, Bekim; Yoshimoto, Maisa; Wang, Yuzhuo; Zielenska, Maria; Squire, Jeremy A

    2008-01-01

    GADD45 genes are epigenetically inactivated in various types of cancer and tumor cell lines. To date, defects of the GADD45 gene family have not been implicated in osteosarcoma (OS) oncogenesis, and the role of this pathway in regulating apoptosis in this tumor is unknown. The therapeutic potential of Gadd45 in OS emerged when our previous studies showed that GADD45A was reexpressed by treatment with the demethylation drug decitabine. In this study, we analyze the OS cell lines MG63 and U2OS and show that on treatment with decitabine, a significant loss of DNA methylation of GADD45A was associated with elevated expression and induction of apoptosis. In vivo affects of decitabine treatment in mice showed that untreated control xenografts exhibited low nuclear staining for Gadd45a protein, whereas the nuclei from xenografts in decitabine-treated mice exhibited increased amounts of protein and elevated apoptosis. To show the specificity of this gene for decitabine-induced apoptosis in OS, GADD45A mRNAs were disrupted using short interference RNA, and the ability of the drug to induce apoptosis was reduced. Understanding the role of demethylation of GADD45A in reexpression of this pathway and restoration of apoptotic control is important for understanding OS oncogenesis and for more targeted therapeutic approaches. PMID:18472964

  1. Demethylation-mediated miR-129-5p up-regulation inhibits malignant phenotype of osteogenic osteosarcoma by targeting Homo sapiens valosin-containing protein (VCP).

    Science.gov (United States)

    Long, Xin Hua; Zhou, Yun Fei; Peng, Ai Fen; Zhang, Zhi Hong; Chen, Xuan Yin; Chen, Wen Zhao; Liu, Jia Ming; Huang, Shan Hu; Liu, Zhi Li

    2015-05-01

    Previous studies demonstrated that increased Homo sapiens valosin-containing protein (VCP) may be involved in osteosarcoma (OS) metastasis. However, the underlying mechanism of VCP over-expression in OS remains unknown. In the present study, we found a significantly negative correlation between miR-129-5p and VCP protein expression in OS tissues with pulmonary metastasis (Spearman's rho, rs = -0.948). Bioinformatical prediction, Luciferase reporter assay, Western blot, and RT-PCR assays performed on OS cells indicated that VCP is a target of miR-129-5p. In addition, three CPG islands in the region of miR-129-5p promoter were detected by bioinformatical prediction, and significantly higher expression of miR-129-5p and lower methylation level of miR-129-2 gene in OS cells treated with 5-Aza-2'-deoxycytidine (a potent DNA demethylating agent) than in those untreated cells were observed. Furthermore, lower migratory and invasive ability was found in cells with elevated miR-129-5p than in those with decreased miR-129-5p. These findings indicated that increased miR-129-5p may be mediated by demethylation and inhibit OS cell migration and invasion by targeting VCP in OS, and targeting miR-129-5p/VCP signaling pathway may serve as a therapeutic strategy for OS management, although further studies will be necessary.

  2. Decitabine-Induced Demethylation of 5′ CpG Island in GADD45A Leads to Apoptosis in Osteosarcoma Cells

    Directory of Open Access Journals (Sweden)

    Khaldoun Al-Romaih

    2008-05-01

    Full Text Available GADD45 genes are epigenetically inactivated in various types of cancer and tumor cell lines. To date, defects of the GADD45 gene family have not been implicated in osteosarcoma (OS oncogenesis, and the role of this pathway in regulating apoptosis in this tumor is unknown. The therapeutic potential of Gadd45 in OS emerged when our previous studies showed that GADD45A was reexpressed by treatment with the demethylation drug decitabine. In this study, we analyze the OS cell lines MG63 and U2OS and show that on treatment with decitabine, a significant loss of DNA methylation of GADD45A was associated with elevated expression and induction of apoptosis. In vivo affects of decitabine treatment in mice showed that untreated control xenografts exhibited low nuclear staining for Gadd45a protein, whereas the nuclei from xenografts in decitabine-treated mice exhibited increased amounts of protein and elevated apoptosis. To show the specificity of this gene for decitabine-induced apoptosis in OS, GADD45A mRNAs were disrupted using short interference RNA, and the ability of the drug to induce apoptosis was reduced. Understanding the role of demethylation of GADD45A in reexpression of this pathway and restoration of apoptotic control is important for understanding OS oncogenesis and for more targeted therapeutic approaches.

  3. 26 CFR 601.502 - Recognized representative.

    Science.gov (United States)

    2010-04-01

    .... 230; (4) Enrolled actuary. Any individual who is enrolled as an actuary by and is in active status with the Joint Board for the Enrollment of Actuaries pursuant to 29 U.S.C. 1242. (5) Other individuals... actuaries, and others); (3) I am authorized to represent the taxpayer(s) identified in the power of...

  4. Tet1 oxidase regulates neuronal gene transcription, active DNA hydroxymethylation, object location memory, and threat recognition memory

    Directory of Open Access Journals (Sweden)

    Dinesh Kumar

    2015-10-01

    Full Text Available A dynamic equilibrium between DNA methylation and demethylation of neuronal activity-regulated genes is crucial for memory processes. However, the mechanisms underlying this equilibrium remain elusive. Tet1 oxidase has been shown to play a key role in the active DNA demethylation in the central nervous system. In this study, we used Tet1 gene knockout (Tet1KO mice to examine the involvement of Tet1 in memory consolidation and storage in the adult brain. We found that Tet1 ablation leads to altered expression of numerous neuronal activity-regulated genes, compensatory upregulation of active demethylation pathway genes, and upregulation of various epigenetic modifiers. Moreover, Tet1KO mice showed an enhancement in the consolidation and storage of threat recognition (cued and contextual fear conditioning and object location memories. We conclude that Tet1 plays a critical role in regulating neuronal transcription and in maintaining the epigenetic state of the brain associated with memory consolidation and storage.

  5. Representing Context in Hypermedia Data Models

    DEFF Research Database (Denmark)

    Hansen, Frank Allan

    2005-01-01

    As computers and software systems move beyond the desktopand into the physical environments we live and workin, the systems are required to adapt to these environmentsand the activities taking place within them. Making applicationscontext-aware and representing context informationalong side...... application data can be a challenging task. Thispaper describes how digital context traditionally has beenrepresented in hypermedia data models and how this representationcan scale to also represent physical context. TheHyCon framework and data model, designed for the developmentof mobile context...

  6. Marc Treib: Representing Landscape Architecture

    DEFF Research Database (Denmark)

    Braae, Ellen Marie

    2008-01-01

    The editor of Representing Landscape Architecture, Marc Treib, argues that there is good reason to evaluate the standard practices of representation that landscape architects have been using for so long. In the rush to the promised land of computer design these practices are now in danger of being...... left by the wayside. The 14 often both fitting and well crafted contributions of this publication offer an approach to how landscape architecture has been and is currently represented; in the design study, in presentation, in criticism, and in the creation of landscape architecture....

  7. Representative process sampling - in practice

    DEFF Research Database (Denmark)

    Esbensen, Kim; Friis-Pedersen, Hans Henrik; Julius, Lars Petersen

    2007-01-01

    Didactic data sets representing a range of real-world processes are used to illustrate "how to do" representative process sampling and process characterisation. The selected process data lead to diverse variogram expressions with different systematics (no range vs. important ranges; trends and....../or periodicity; different nugget effects and process variations ranging from less than one lag to full variogram lag). Variogram data analysis leads to a fundamental decomposition into 0-D sampling vs. 1-D process variances, based on the three principal variogram parameters: range, sill and nugget effect...

  8. Genome-wide methylation and expression profiling identifies promoter characteristics affecting demethylation-induced gene up-regulation in melanoma

    Directory of Open Access Journals (Sweden)

    Halaban Ruth

    2010-02-01

    Full Text Available Abstract Background Abberant DNA methylation at CpG dinucleotides represents a common mechanism of transcriptional silencing in cancer. Since CpG methylation is a reversible event, tumor supressor genes that have undergone silencing through this mechanism represent promising targets for epigenetically active anti-cancer therapy. The cytosine analog 5-aza-2'-deoxycytidine (decitabine induces genomic hypomethylation by inhibiting DNA methyltransferase, and is an example of an epigenetic agent that is thought to act by up-regulating silenced genes. Methods It is unclear why decitabine causes some silenced loci to re-express, while others remain inactive. By applying data-mining techniques to large-scale datasets, we attempted to elucidate the qualities of promoter regions that define susceptibility to the drug's action. Our experimental data, derived from melanoma cell strains, consist of genome-wide gene expression data before and after treatment with decitabine, as well as genome-wide data on un-treated promoter methylation status, and validation of specific genes by bisulfite sequencing. Results We show that the combination of promoter CpG content and methylation level informs the ability of decitabine treatment to up-regulate gene expression. Promoters with high methylation levels and intermediate CpG content appear most susceptible to up-regulation by decitabine, whereas few of those highly methylated promoters with high CpG content are up-regulated. For promoters with low methylation levels, those with high CpG content are more likely to be up-regulated, whereas those with low CpG content are underrepresented among up-regulated genes. Conclusions Clinically, elucidating the patterns of action of decitabine could aid in predicting the likelihood of up-regulating epigenetically silenced tumor suppressor genes and others from pathways involved with tumor biology. As a first step toward an eventual translational application, we build a classifier

  9. Yucca Mountain Climate Technical Support Representative

    Energy Technology Data Exchange (ETDEWEB)

    Sharpe, Saxon E

    2007-10-23

    The primary objective of Project Activity ORD-FY04-012, “Yucca Mountain Climate Technical Support Representative,” was to provide the Office of Civilian Radioactive Waste Management (OCRWM) with expertise on past, present, and future climate scenarios and to support the technical elements of the Yucca Mountain Project (YMP) climate program. The Climate Technical Support Representative was to explain, defend, and interpret the YMP climate program to the various audiences during Site Recommendation and License Application. This technical support representative was to support DOE management in the preparation and review of documents, and to participate in comment response for the Final Environmental Impact Statement, the Site Recommendation Hearings, the NRC Sufficiency Comments, and other forums as designated by DOE management. Because the activity was terminated 12 months early and experience a 27% reduction in budget, it was not possible to complete all components of the tasks as originally envisioned. Activities not completed include the qualification of climate datasets and the production of a qualified technical report. The following final report is an unqualified summary of the activities that were completed given the reduced time and funding.

  10. Demethylation by 5-aza-2'-deoxycytidine in colorectal cancer cells targets genomic DNA whilst promoter CpG island methylation persists

    Directory of Open Access Journals (Sweden)

    Kim Kyu-Tae

    2010-07-01

    Full Text Available Abstract Background DNA methylation and histone acetylation are epigenetic modifications that act as regulators of gene expression. Aberrant epigenetic gene silencing in tumours is a frequent event, yet the factors which dictate which genes are targeted for inactivation are unknown. DNA methylation and histone acetylation can be modified with the chemical agents 5-aza-2'-deoxycytidine (5-aza-dC and Trichostatin A (TSA respectively. The aim of this study was to analyse de-methylation and re-methylation and its affect on gene expression in colorectal cancer cell lines treated with 5-aza-dC alone and in combination with TSA. We also sought to identify methylation patterns associated with long term reactivation of previously silenced genes. Method Colorectal cancer cell lines were treated with 5-aza-dC, with and without TSA, to analyse global methylation decreases by High Performance Liquid Chromatography (HPLC. Re-methylation was observed with removal of drug treatments. Expression arrays identified silenced genes with differing patterns of expression after treatment, such as short term reactivation or long term reactivation. Sodium bisulfite sequencing was performed on the CpG island associated with these genes and expression was verified with real time PCR. Results Treatment with 5-aza-dC was found to affect genomic methylation and to a lesser extent gene specific methylation. Reactivated genes which remained expressed 10 days post 5-aza-dC treatment featured hypomethylated CpG sites adjacent to the transcription start site (TSS. In contrast, genes with uniformly hypermethylated CpG islands were only temporarily reactivated. Conclusion These results imply that 5-aza-dC induces strong de-methylation of the genome and initiates reactivation of transcriptionally inactive genes, but this does not require gene associated CpG island de-methylation to occur. In addition, for three of our selected genes, hypomethylation at the TSS of an epigenetically

  11. Representative process sampling - in practice

    DEFF Research Database (Denmark)

    Esbensen, Kim; Friis-Pedersen, Hans Henrik; Julius, Lars Petersen

    2007-01-01

    /or periodicity; different nugget effects and process variations ranging from less than one lag to full variogram lag). Variogram data analysis leads to a fundamental decomposition into 0-D sampling vs. 1-D process variances, based on the three principal variogram parameters: range, sill and nugget effect......Didactic data sets representing a range of real-world processes are used to illustrate "how to do" representative process sampling and process characterisation. The selected process data lead to diverse variogram expressions with different systematics (no range vs. important ranges; trends and...... presented cases of variography either solved the initial problems or served to understand the reasons and causes behind the specific process structures revealed in the variograms. Process Analytical Technologies (PAT) are not complete without process TOS....

  12. Judgments of and by Representativeness

    Science.gov (United States)

    1981-05-15

    probably agree that John Updike is a more representative American writer than Norman Mailer. rlearly, such a judgment does not have a frequentistic...example, in an early study we presented people with the following description, " John is 27 years old, with an outgoing personality. At college he was an...outstanding athlete but did not show much ability or interest in in- tellectual matters". We found that John was judged to be more likely to be "a gym

  13. Characterization of different commercial soybean peroxidase preparations and the use of the enzyme for the N-demethylation of methyl-N-methylanthranilate to produce the food flavour methylanthranilate

    NARCIS (Netherlands)

    Haandel, van M.J.H.; Saraber, F.C.E.; Boersma, M.G.; Laane, C.; Fleming, Y.; Weenen, H.; Rietjens, I.M.C.M.

    2000-01-01

    The potential of different peroxidase preparations for the N-demethylation of methyl N-methylanthranilate to produce the food flavor methylanthranilate (MA) was investigated. All tested peroxidase preparations were able to catalyze the N-dealkylation. The tested soybean preparations vary widely with

  14. Representing culture in interstellar messages

    Science.gov (United States)

    Vakoch, Douglas A.

    2008-09-01

    As scholars involved with the Search for Extraterrestrial Intelligence (SETI) have contemplated how we might portray humankind in any messages sent to civilizations beyond Earth, one of the challenges they face is adequately representing the diversity of human cultures. For example, in a 2003 workshop in Paris sponsored by the SETI Institute, the International Academy of Astronautics (IAA) SETI Permanent Study Group, the International Society for the Arts, Sciences and Technology (ISAST), and the John Templeton Foundation, a varied group of artists, scientists, and scholars from the humanities considered how to encode notions of altruism in interstellar messages art_science/2003>. Though the group represented 10 countries, most were from Europe and North America, leading to the group's recommendation that subsequent discussions on the topic should include more globally representative perspectives. As a result, the IAA Study Group on Interstellar Message Construction and the SETI Institute sponsored a follow-up workshop in Santa Fe, New Mexico, USA in February 2005. The Santa Fe workshop brought together scholars from a range of disciplines including anthropology, archaeology, chemistry, communication science, philosophy, and psychology. Participants included scholars familiar with interstellar message design as well as specialists in cross-cultural research who had participated in the Symposium on Altruism in Cross-cultural Perspective, held just prior to the workshop during the annual conference of the Society for Cross-cultural Research . The workshop included discussion of how cultural understandings of altruism can complement and critique the more biologically based models of altruism proposed for interstellar messages at the 2003 Paris workshop. This paper, written by the chair of both the Paris and Santa Fe workshops, will explore the challenges of communicating concepts of altruism that draw on both biological and cultural models.

  15. Semantic Representatives of the Concept

    Directory of Open Access Journals (Sweden)

    Elena N. Tsay

    2013-01-01

    Full Text Available In the article concept as one of the principle notions of cognitive linguistics is investigated. Considering concept as culture phenomenon, having language realization and ethnocultural peculiarities, the description of the concept “happiness” is presented. Lexical and semantic paradigm of the concept of happiness correlates with a great number of lexical and semantic variants. In the work semantic representatives of the concept of happiness, covering supreme spiritual values are revealed and semantic interpretation of their functioning in the Biblical discourse is given.

  16. Epigenetic reactivation of Nrf2 in murine prostate cancer TRAMP C1 cells by natural phytochemicals Z-ligustilide and Radix angelica sinensis via promoter CpG demethylation.

    Science.gov (United States)

    Su, Zheng-Yuan; Khor, Tin Oo; Shu, Limin; Lee, Jong Hun; Saw, Constance Lay-Lay; Wu, Tien-Yuan; Huang, Ying; Suh, Nanjoo; Yang, Chung S; Conney, Allan H; Wu, Qing; Kong, Ah-Ng Tony

    2013-03-18

    Cancer development has been linked to epigenetic modifications of cancer oncogenes and tumor suppressor genes; in advanced metastatic cancers, severe epigenetic modifications are present. We previously demonstrated that the progression of prostate tumors in TRAMP mice is associated with methylation silencing of the Nrf2 promoter and a reduced level of transcription of Nrf2 and Nrf2 target genes. Radix Angelicae Sinensis (RAS; Danggui) is a medicinal herb and health food supplement that has been widely used in Asia for centuries. Z-Ligustilide (Lig) is one of the bioactive components of RAS. We investigated the potential of Lig and RAS to restore Nrf2 gene expression through epigenetic modification in TRAMP C1 cells. Lig and RAS induced the mRNA and protein expression of endogenous Nrf2 and Nrf2 downstream target genes, such as HO-1, NQO1, and UGT1A1. Bisulfite genomic sequencing revealed that Lig and RAS treatment decreased the level of methylation of the first five CpGs of the Nrf2 promoter. A methylation DNA immunoprecipitation assay demonstrated that Lig and RAS significantly decreased the relative amount of methylated DNA in the Nrf2 gene promoter region. Lig and RAS also inhibited DNA methyltransferase activity in vitro. Collectively, these results suggest that Lig and RAS are able to demethylate the Nrf2 promoter CpGs, resulting in the re-expression of Nrf2 and Nrf2 target genes. Epigenetic modifications of genes, including Nrf2, may therefore contribute to the overall health benefits of RAS, including the anticancer effect of RAS and its bioactive component, Lig.

  17. Representative mass reduction in sampling

    DEFF Research Database (Denmark)

    Petersen, Lars; Esbensen, Harry Kim; Dahl, Casper Kierulf

    2004-01-01

    We here present a comprehensive survey of current mass reduction principles and hardware available in the current market. We conduct a rigorous comparison study of the performance of 17 field and/or laboratory instruments or methods which are quantitatively characterized (and ranked) for accuracy...... always be representative in the full Theory of Sampling (TOS) sense. This survey also allows empirical verification of the merits of the famous ??Gy?s formula?? for order-of-magnitude estimation of the Fundamental Sampling Error (FSE).......We here present a comprehensive survey of current mass reduction principles and hardware available in the current market. We conduct a rigorous comparison study of the performance of 17 field and/or laboratory instruments or methods which are quantitatively characterized (and ranked) for accuracy...... dividers, the Boerner Divider, the ??spoon method??, alternate/fractional shoveling and grab sampling. Only devices based on riffle splitting principles (static or rotational) passes the ultimate representativity test (with minor, but significant relative differences). Grab sampling, the overwhelmingly...

  18. Representing Conversations for Scalable Overhearing

    CERN Document Server

    Gutnik, G; 10.1613/jair.1829

    2011-01-01

    Open distributed multi-agent systems are gaining interest in the academic community and in industry. In such open settings, agents are often coordinated using standardized agent conversation protocols. The representation of such protocols (for analysis, validation, monitoring, etc) is an important aspect of multi-agent applications. Recently, Petri nets have been shown to be an interesting approach to such representation, and radically different approaches using Petri nets have been proposed. However, their relative strengths and weaknesses have not been examined. Moreover, their scalability and suitability for different tasks have not been addressed. This paper addresses both these challenges. First, we analyze existing Petri net representations in terms of their scalability and appropriateness for overhearing, an important task in monitoring open multi-agent systems. Then, building on the insights gained, we introduce a novel representation using Colored Petri nets that explicitly represent legal joint conv...

  19. Structure-activity relationship of benzophenanthridine alkaloids from Zanthoxylum rhoifolium having antimicrobial activity.

    Directory of Open Access Journals (Sweden)

    Luciana de C Tavares

    Full Text Available Zanthoxylum rhoifolium (Rutaceae is a plant alkaloid that grows in South America and has been used in Brazilian traditional medicine for the treatment of different health problems. The present study was designed to evaluate the antimicrobial activity of the steam bark crude methanol extract, fractions, and pure alkaloids of Z. rhoifolium. Its stem bark extracts exhibited a broad spectrum of antimicrobial activity, ranging from 12.5 to 100 µg/mL using bioautography method, and from 125 to 500 µg/mL in the microdilution bioassay. From the dichloromethane basic fraction, three furoquinoline alkaloids (1-3, and nine benzophenanthridine alkaloids (4-12 were isolated and the antimicrobial activity of the benzophenanthridine alkaloids is discussed in terms of structure-activity relationships. The alkaloid with the widest spectrum of activity was chelerythrine (10, followed by avicine (12 and dihydrochelerythrine (4. The minimal inhibitory concentrations of chelerythrine, of 1.50 µg/mL for all bacteria tested, and between 3.12 and 6.25 µg/mL for the yeast tested, show this compound to be a more powerful antimicrobial agent when compared with the other active alkaloids isolated from Z. rhoifolium. To verify the potential importance of the methylenedioxy group (ring A of these alkaloids, chelerythrine was selected to represent the remainder of the benzophenanthridine alkaloids isolated in this work and was subjected to a demethylation reaction giving derivative 14. Compared to chelerythrine, the derivative (14 was less active against the tested bacteria and fungi. Kinetic measurements of the bacteriolytic activities of chelerythrine against the bacteria Bacillus subtilis (Gram-positive and Escherichia coli (Gram-negative were determined by optical density based on real time assay, suggesting that its mechanism of action is not bacteriolytic. The present study did not detect hemolytic effects of chelerythrine on erythrocytes and found a protective

  20. [Effect of 5-aza-CdR demethylation on expression of SHP-1 and C-kit genes in leukemia HL-60 cells].

    Science.gov (United States)

    Meng, Zhen; Li, Ying-Hua; Wang, Dong-Mei; Luo, Jian-Min

    2014-12-01

    This study was aimed to investigate the expression level of SHP-1 and C-kit genes in acute leukemia HL-60 cells and effect of 5-aza-CdR demethylation on expression of SHP-1 and C-kit genes. RT-PCR was used to detect the mRNA expression level of SHP-1 and C-kit mRNA in HL-60 cells of the drug-treated group and control group.The methylation specific PCR (MSP) was applied to measure the methylation status of SHP-1 and C-kit genes in HL-60 cells.The results showed that after being treated with 5-aza-CdR, the recovery of SHP-1 gene expression was observed in HL-60 cells in which SHP-1 mRNA originally was not expressed. Meanwhile, the high expression level of C-kit mRNA in HL-60 cells was decreased. When HL-60 cells were treated with 0, 0.5, 1.0, 2.0 µmol/L 5-aza-CdR, the demethylation effect was enhanced, the expression of SHP-1 mRNA displayed an ascending tendency, and the expression of C-kit mRNA showed an descending tendency in dose-dependent manner (P HL-60 cells and recovery of expression after treatment with 5-aza-CdR suggest that the hypermethylation of SHP-1 gene relates with pathogenesis of leukemia, and the abnormal increase of C-kit mRNA expression maybe exist in formation of leukemia. The effect of 5-aza-CdR on expression of SHP-1 and C-kit shows dose-dependency, the higher the 5-aza-CdR concentration, the higher the SHP-1 expression and the lower the C-kit expression, moreover, the effect of 5-aza-CdR shows time-dependency in specific concentration.The SHP-1 mRNA expression negatively correlates with C-kit mRNA expression, suggesting that the decrease or absence of SHP-1 expression in leukemia cells weakens the negative regulation on C-kit signaling pathway, thus plays a role in the formation of leukemia.

  1. [Demethylation effect of inhibitor As2O3 on expression of SHP-1 and C-kit genes in leukemia HL-60 cells].

    Science.gov (United States)

    Meng, Zhen; Wang, Dong-Mei; Li, Ying-Hua; Liu, Xiao; Guo, Su-Qing; Luo, Jian-Min

    2013-06-01

    This study was aimed to investigate the expression level of SHP-1 and C-kit genes in acute leukemia HL-60 cells and effect of inhibitor As2O3 demethylation on SHP-1 and C-kit genes expression. RT-PCR was used to detect the expression level of SHP-1 and C-kit mRNA in drug-treated cell group and control group. The methylation specific PCR (MSP) was applied to measure the methylation status of SHP-1 gene in HL-60 cells. The results showed that after being treated with As2O3 the recovery of SHP-1 gene expression was observed in HL-60 cells in which SHP-1 mRNA originally did not expressed, meanwhile the expression level of C-kit mRNA in HL-60 cells with high expression decreased. When HL-60 cells were treated with As2O3 of 1.0, 2.5, 5.0 µmol/L, the demethylation effects was enhanced, the expression of SHP-1 mRNA displayed an ascending tendency, and expression of C-kit mRNA showed an descending tendency in dose-dependent manner (P HL-60 cells and recovery of expression after treatment with As2O3 suggest the hypermethylation of SHP-1 gene related with pathogenesis of leukemia, and the abnormal increase of C-kit mRNA expression maybe exist in formation of leukemia. The effect of As2O3 on expression of SHP-1 and C-kit shows dose-dependency, the higher the As2O3 concentration, the higher the SHP-1 expression and the lower the C-kit expression, moreover, the effect of As2O3 shows time-dependency in specific concentration. The SHP-1 mRNA expression negatively relates with C-kit mRNA expression, suggesting that the decrease or absence of SHP-1 expression in leukemia cells weakens the negative regulation on C-kit signaling pathway, thus plays a role in the formation of leukemia.

  2. Determination of the Proportion of Total Soil Extracellular Acid Phosphomonoesterase (E.C. 3.1.3.2 Activity Represented by Roots in the Soil of Different Forest Ecosystems

    Directory of Open Access Journals (Sweden)

    Klement Rejsek

    2012-01-01

    Full Text Available The aim of this study is to present a new method for determining the root-derived extracellular acid phosphomonoesterase (EAPM activity fraction within the total EAPM activity of soil. EAPM activity was determined for roots, organic and mineral soil. Samples were collected using paired PVC cylinders, inserted to a depth of 15 cm, within seven selected forest stands. Root-derived EAPM formed between 4 and18% of the total EAPM activity of soil from forests of differing maturity. A new approach, presented in this work, enables separation of root-derived EAPM activity from total soil EAPM. Separation of root-derived EAPM from soil provides a better understanding of its role in P-cycling in terrestrial ecosystems. The method presented in this work is a first step towards the separation of root- and microbe-derived EAPM in soils, which are thought to possess different kinetic properties and different sensitivity to environmental change.

  3. Learning to represent visual input.

    Science.gov (United States)

    Hinton, Geoffrey E

    2010-01-12

    One of the central problems in computational neuroscience is to understand how the object-recognition pathway of the cortex learns a deep hierarchy of nonlinear feature detectors. Recent progress in machine learning shows that it is possible to learn deep hierarchies without requiring any labelled data. The feature detectors are learned one layer at a time and the goal of the learning procedure is to form a good generative model of images, not to predict the class of each image. The learning procedure only requires the pairwise correlations between the activations of neuron-like processing units in adjacent layers. The original version of the learning procedure is derived from a quadratic 'energy' function but it can be extended to allow third-order, multiplicative interactions in which neurons gate the pairwise interactions between other neurons. A technique for factoring the third-order interactions leads to a learning module that again has a simple learning rule based on pairwise correlations. This module looks remarkably like modules that have been proposed by both biologists trying to explain the responses of neurons and engineers trying to create systems that can recognize objects.

  4. [Lactase deficiency among representatives of various nationalities of Siberia].

    Science.gov (United States)

    Zhvavyĭ, N F; Kozlov, A I; Kondik, V M

    1991-01-01

    Some features of lactase tolerance were investigated in representatives of varying groups of indigenous population in Siberia-Mansi, Khanty, Nenets, Buryats. The indirect method was used to evaluate lactase activity. A total of 92 subjects were investigated. It was found that 32% of the representatives of the Urals population group and 53% of Buryats were capable of lactase assimilating. The data obtained correspond to the cultural-genetic hypothesis on the nature of lactase tolerance in the representatives of different ethnic groups.

  5. Rescue of Early bace-1 and Global DNA Demethylation by S-Adenosylmethionine Reduces Amyloid Pathology and Improves Cognition in an Alzheimer’s Model

    Science.gov (United States)

    Do Carmo, Sonia; Hanzel, Cecilia E.; Jacobs, Marie L.; Machnes, Ziv; Iulita, M. Florencia; Yang, Jingyun; Yu, Lei; Ducatenzeiler, Adriana; Danik, Marc; Breuillaud, Lionel S.; Bennett, David A.; Szyf, Moshe; Cuello, A. Claudio

    2016-01-01

    General DNA hypomethylation is associated with Alzheimer’s disease (AD), but it is unclear when DNA hypomethylation starts or plays a role in AD pathology or whether DNA re-methylation would rescue early amyloid-related cognitive impairments. In an APP transgenic mouse model of AD-like amyloid pathology we found that early intraneuronal amyloid beta build-up is sufficient to unleash a global and beta-site amyloid precursor protein cleaving enzyme 1 (bace-1) DNA demethylation in AD-vulnerable brain regions. S-adenosylmethionine administration at these early stages abolished this hypomethylation, diminished the amyloid pathology and restored cognitive capabilities. To assess a possible human significance of findings, we examined the methylation at 12 CpGs sites in the bace-1 promoter, using genome-wide DNA methylation data from 740 postmortem human brains. Thus, we found significant associations of bace-1 promoter methylation with β-amyloid load among persons with AD dementia, and PHFtau tangle density. Our results support a plausible causal role for the earliest amyloid beta accumulation to provoke DNA hypomethylation, influencing AD pathological outcomes. PMID:27681803

  6. Induced overexpression of cytochrome P450 sterol 14α-demethylase gene (CYP51) correlates with sensitivity to demethylation inhibitors (DMIs) in Sclerotinia homoeocarpa.

    Science.gov (United States)

    Ma, Bangya; Tredway, Lane P

    2013-12-01

    The fungus Sclerotinia homoeocarpa causes dollar spot, the most important turfgrass disease worldwide. Demethylation inhibitor (DMI) fungicides have been relied upon heavily to manage this disease. Presently, populations of S. homoeocarpa with reduced sensitivity or resistance to DMIs are widespread in the United States. Cytochrome P450 sterol 14α-demethylase (ShCYP51) and its flanking regions were identified and sequenced in 29 isolates of S. homoeocarpa with a range of DMI sensitivities. No modifications were found in the gene coding and upstream regions that were consistently related to DMI sensitivity. In the absence of propiconazole, ShCYP51 was expressed at a similar low level among DMI baseline and resistant isolates. In the presence of propiconazole, DMI-resistant isolates were induced to express ShCYP51 at significantly higher levels than baseline isolates by propiconazole at 5 mg L(-1) for 5 h or at 0.5 mg L(-1) for 72 h. The ShCYP51 expression level after 72 h exposure to 0.5 mg L(-1) of propiconazole was linearly related to EC50 values and ΔRG (the change in relative growth rate over time), with R(2) values equal to 83.7 and 90.0% respectively. Induced overexpression of ShCYP51 in resistant isolates following DMI exposure is an important factor determining DMI sensitivity in S. homoeocarpa. © 2013 Society of Chemical Industry.

  7. Rescue of Early bace-1 and Global DNA Demethylation by S-Adenosylmethionine Reduces Amyloid Pathology and Improves Cognition in an Alzheimer's Model.

    Science.gov (United States)

    Do Carmo, Sonia; Hanzel, Cecilia E; Jacobs, Marie L; Machnes, Ziv; Iulita, M Florencia; Yang, Jingyun; Yu, Lei; Ducatenzeiler, Adriana; Danik, Marc; Breuillaud, Lionel S; Bennett, David A; Szyf, Moshe; Cuello, A Claudio

    2016-09-29

    General DNA hypomethylation is associated with Alzheimer's disease (AD), but it is unclear when DNA hypomethylation starts or plays a role in AD pathology or whether DNA re-methylation would rescue early amyloid-related cognitive impairments. In an APP transgenic mouse model of AD-like amyloid pathology we found that early intraneuronal amyloid beta build-up is sufficient to unleash a global and beta-site amyloid precursor protein cleaving enzyme 1 (bace-1) DNA demethylation in AD-vulnerable brain regions. S-adenosylmethionine administration at these early stages abolished this hypomethylation, diminished the amyloid pathology and restored cognitive capabilities. To assess a possible human significance of findings, we examined the methylation at 12 CpGs sites in the bace-1 promoter, using genome-wide DNA methylation data from 740 postmortem human brains. Thus, we found significant associations of bace-1 promoter methylation with β-amyloid load among persons with AD dementia, and PHFtau tangle density. Our results support a plausible causal role for the earliest amyloid beta accumulation to provoke DNA hypomethylation, influencing AD pathological outcomes.

  8. 10 CFR 63.332 - Representative volume.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Representative volume. 63.332 Section 63.332 Energy... Protection Standards § 63.332 Representative volume. (a) The representative volume is the volume of ground... radionuclides released from the Yucca Mountain disposal system that will be in the representative volume....

  9. Epigenetic identification of ZNF545 as a functional tumor suppressor in multiple myeloma via activation of p53 signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Yu [Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing (China); Zhan, Qian [The Center for Clinical Molecular Medical Detection, The First Affiliated Hospital of Chongqing Medical University, Chongqing (China); Xu, Hongying [Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing (China); Li, Lili; Li, Chen [Cancer Epigenetics Laboratory, Department of Clinical Oncology, Sir YK Pao Center for Cancer and Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong and CUHK Shenzhen Research Institute (Hong Kong); Xiao, Qian; Xiang, Shili; Hui, Tianli [Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing (China); Xiang, Tingxiu, E-mail: larissaxiang@163.com [Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing (China); Ren, Guosheng, E-mail: rengs726@126.com [Chongqing Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing (China)

    2016-06-10

    The KRAB–zinc-finger protein ZNF545 was recently identified as a potential suppressor gene in several tumors. However, the regulatory mechanisms of ZNF545 in tumorigenesis remain unclear. In this study, we investigated the expression and roles of ZNF545 in multiple myeloma (MM). ZNF545 was frequently downregulated in MM tissues compared with non-tumor bone marrow tissues. ZNF545 expression was silenced by promoter methylation in MM cell lines, and could be restored by demethylation treatment. ZNF545 methylation was detected in 28.3% of MM tissues, compared with 4.3% of normal bone marrow tissues. ZNF545 transcriptionally activated the p53 signaling pathway but had no effect on Akt in MM, whereas ectopic expression of ZNF545 in silenced cells suppressed their proliferation and induced apoptosis. We therefore identified ZNF545 as a novel tumor suppressor inhibiting tumor growth through activation of the p53 pathway in MM. Moreover, tumor-specific methylation of ZNF545 may represent an epigenetic biomarker for MM diagnosis, and a potential target for specific therapy. -- Highlights: •Downregulated ZNF545 in MM tissues and cell lines and ectopic expression of ZNF545 suppresses tumor growth. •Tumor-specific methylation of ZNF545 represents an epigenetic biomarker for MM diagnosis, and a potential target for specific therapy. •ZNF545 exerts its tumor suppressive effects via transcriptional activating p53 pathway.

  10. Neoglycoconjugate of Tetrasaccharide Representing One Repeating Unit of the Streptococcus pneumoniae Type 14 Capsular Polysaccharide Induces the Production of Opsonizing IgG1 Antibodies and Possesses the Highest Protective Activity As Compared to Hexa- and Octasaccharide Conjugates

    Directory of Open Access Journals (Sweden)

    Ekaterina A. Kurbatova

    2017-06-01

    Full Text Available Identifying protective synthetic oligosaccharide (OS epitopes of Streptococcus pneumoniae capsular polysaccharides (CPs is an indispensable step in the development of third-generation carbohydrate pneumococcal vaccines. Synthetic tetra-, hexa-, and octasaccharide structurally related to CP of S. pneumoniae type 14 were coupled to bovine serum albumin (BSA, adjuvanted with aluminum hydroxide, and tested for their immunogenicity in mice upon intraperitoneal prime-boost immunizations. Injections of the conjugates induced production of opsonizing anti-OS IgG1 antibodies (Abs. Immunization with the tetra- and octasaccharide conjugates stimulated the highest titers of the specific Abs. Further, the tetrasaccharide ligand demonstrated the highest ability to bind OS and CP Abs. Murine immune sera developed against tetra- and octasaccharide conjugates promoted pathogen opsonization to a higher degree than antisera against conjugated hexasaccharide. For the first time, the protective activities of these glycoconjugates were demonstrated in mouse model of generalized pneumococcal infections. The tetrasaccharide conjugate possessed the highest protective activities. Conversely, the octasaccharide conjugate had lower protective activities and the lowest one showed the hexasaccharide conjugate. Sera against all of the glycoconjugates passively protected naive mice from pneumococcal infections. Given that the BSA-tetrasaccharide induced the most abundant yield of specific Abs and the best protective activity, this OS may be regarded as the most promising candidate for the development of conjugated vaccines against S. pneumoniae type 14 infections.

  11. Stability of XIST repression in relation to genomic imprinting following global genome demethylation in a human cell line

    OpenAIRE

    E.S.S. de Araújo; Vasques, L.R.; Stabellini,R.; A.C.V. Krepischi; Pereira, L.V.

    2014-01-01

    DNA methylation is essential in X chromosome inactivation and genomic imprinting, maintaining repression of XIST in the active X chromosome and monoallelic repression of imprinted genes. Disruption of the DNA methyltransferase genes DNMT1 and DNMT3B in the HCT116 cell line (DKO cells) leads to global DNA hypomethylation and biallelic expression of the imprinted gene IGF2 but does not lead to reactivation of XIST expression, suggesting thatXIST repression is due to a more stable epigenetic mar...

  12. Stability of XIST repression in relation to genomic imprinting following global genome demethylation in a human cell line

    Energy Technology Data Exchange (ETDEWEB)

    Araújo, E.S.S. de [Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP (Brazil); Centro Internacional de Pesquisa, A.C. Camargo Cancer Center, São Paulo, SP (Brazil); Vasques, L.R. [Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP (Brazil); Stabellini, R.; Krepischi, A.C.V. [Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP (Brazil); Centro Internacional de Pesquisa, A.C. Camargo Cancer Center, São Paulo, SP (Brazil); Pereira, L.V. [Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP (Brazil)

    2014-10-17

    DNA methylation is essential in X chromosome inactivation and genomic imprinting, maintaining repression of XIST in the active X chromosome and monoallelic repression of imprinted genes. Disruption of the DNA methyltransferase genes DNMT1 and DNMT3B in the HCT116 cell line (DKO cells) leads to global DNA hypomethylation and biallelic expression of the imprinted gene IGF2 but does not lead to reactivation of XIST expression, suggesting that XIST repression is due to a more stable epigenetic mark than imprinting. To test this hypothesis, we induced acute hypomethylation in HCT116 cells by 5-aza-2′-deoxycytidine (5-aza-CdR) treatment (HCT116-5-aza-CdR) and compared that to DKO cells, evaluating DNA methylation by microarray and monitoring the expression of XIST and imprinted genes IGF2, H19, and PEG10. Whereas imprinted genes showed biallelic expression in HCT116-5-aza-CdR and DKO cells, the XIST locus was hypomethylated and weakly expressed only under acute hypomethylation conditions, indicating the importance of XIST repression in the active X to cell survival. Given that DNMT3A is the only active DNMT in DKO cells, it may be responsible for ensuring the repression of XIST in those cells. Taken together, our data suggest that XIST repression is more tightly controlled than genomic imprinting and, at least in part, is due to DNMT3A.

  13. Efecto de actividades turísticas sobre el comportamiento de fauna representativa de las Islas Galápagos, Ecuador Short-term effects of tourism activities on the behavior of representative fauna on the Galapagos Islands, Ecuador

    Directory of Open Access Journals (Sweden)

    Fernanda González-Pérez

    2010-01-01

    Full Text Available Fueron consideradas clave para actividades turísticas en 16 sitios de las Islas Galápagos: la raya sartén marmoleada (Taeniura meyeri, raya águila (Aetobatus narinari, tiburón de aleta blanca (Triaenodon obesus, tortuga verde (Chelonia mydas, cormorán no volador (Phalacrocorax harrisi y lobo marino de Galápagos (Zalophus califórnianus, con el objetivo de analizar reacciones a corto plazo ante actividades de buceo apnea o "snorkeling", buceo autónomo o "scuba", paseos en bote o "panga-ride" y caminatas. Para cada especie se documentó su comportamiento al momento del encuentro con los turistas y su reacción ante dicha situación. El uso del Análisis de Correspondencias reveló que el tipo de reacción de las especies depende significativamente de la actividad turística, a excepción de las rayas sartén marmoleada y águila. Asimismo, los análisis indican que, a nivel de especie, cada actividad turística estuvo asociada significativamente con reacciones animales particulares. Esto sugiere que las especies analizadas son sensibles ante determinadas actividades turísticas, por lo que se deberían implementar recomendaciones de manejo a fin de garantizar la sustentabilidad del ecoturismo.This study focused on the short-term reactions of six key species (Taeniura meyeri, Aetobatus narinari, Triaendon obesus, Chelonia mydas, Phalacrocorax harrisi, and Zalophus califórnianus during tourism activities (SCUBA diving, panga-ride, snorkeling, and hiking at 16 tourist sites on the islands. For each species we recorded its behavior when first encountering tourists and its reaction following this encounter. A Correspondence Analysis revealed that the type of reaction of the species depended significantly on the type of touristic activity, with the exception of the black spotted and eagle rays. Moreover, the analysis showed that, for each species, the different tourist activities were significantly associated with particular animal activities

  14. Posttranslational Modifications of the Histone 3 Tail and Their Impact on the Activity of Histone Lysine Demethylases In Vitro

    DEFF Research Database (Denmark)

    Lohse, Brian; Helgstrand, Charlotte; Andersson, Jan Legaard;

    2013-01-01

    ) and some combinations were characterized on full length (FL) KDM4A and KDM4C. We found that the substrates combining trimethylated K4 and K9 resulted in a significant increase in the catalytic activity for FL-KDM4A. For the truncated versions of KDM4A and KDM4C a two-fold increase in the catalytic activity...... substrates phosphorylated at T11 could not be demethylated by neither truncated nor full length KDM4A and KDM4C, suggesting that phosphorylation of threonine 11 prevents demethylation of the H3K9me3 mark on the same peptide. Acetylation of K14 was also found to influence demethylation rates significantly....... Thus, for truncated KDM4A, acetylation on K14 of the substrate leads to an increase in enzymatic catalytic efficiency (kcat/Km), while for truncated KDM4C it induces a decrease, primarily caused by changes in Km. This study demonstrates that demethylation activities towards trimethylated H3K9...

  15. Aging-dependent demethylation of regulatory elements correlates with chromatin state and improved β-cell function

    Science.gov (United States)

    Avrahami, Dana; Li, Changhong; Zhang, Jia; Schug, Jonathan; Avrahami, Ran; Rao, Shilpa; Stadler, Michael B.; Burger, Lukas; Schübeler, Dirk; Glaser, Benjamin; Kaestner, Klaus H.

    2015-01-01

    Aging is driven by changes of the epigenetic state that are only partially understood. We performed a comprehensive epigenomic analysis of the pancreatic β cell, key player in glucose homeostasis, in adolescent and very old mice. We observe a global methylation drift resulting in an overall more leveled methylome in old β cells. Importantly, we discover targeted changes in the methylation status of β cell proliferation and function genes that go against the global methylation drift, are specific to β cells, and correlate with repression of the proliferation program and activation of metabolic regulators. These targeted alterations are associated with specific chromatin marks and transcription factor occupancy in young β cells. Strikingly, we find β cell function improved in aged mice, as predicted by the changes in methylome and transcriptome. Thus, aging of terminally differentiated cells in mammals is not always coupled to functional decline. PMID:26321660

  16. Overexpression of ShCYP51B and ShatrD in Sclerotinia homoeocarpa isolates exhibiting practical field resistance to a demethylation inhibitor fungicide.

    Science.gov (United States)

    Hulvey, Jon; Popko, James T; Sang, Hyunkyu; Berg, Andrew; Jung, Geunhwa

    2012-09-01

    We investigated genetic factors that govern the reduced propiconazole sensitivity of Sclerotinia homoeocarpa field isolates collected during a 2-year field efficacy study on dollar spot disease of turf in five New England sites. These isolates displayed a >50-fold range of in vitro sensitivity to a sterol demethylation inhibitor (DMI) fungicide, propiconazole, making them ideal for investigations of genetic mechanisms of reduced DMI sensitivity. The CYP51 gene homolog in S. homoeocarpa (ShCYP51B), encoding the enzyme target of DMIs, is likely a minor genetic factor for reduced propiconazole sensitivity, since there were no differences in constitutive relative expression (RE) values and only 2-fold-higher induced RE values for insensitive than for sensitive isolate groups. Next, we mined RNA-Seq transcriptome data for additional genetic factors and found evidence for the overexpression of a homolog of Botrytis cinerea atrD (BcatrD), ShatrD, a known efflux transporter of DMI fungicides. The ShatrD gene showed much higher constitutive and induced RE values for insensitive isolates. Several polymorphisms were found upstream of ShatrD but were not definitively linked to overexpression. The screening of constitutive RE values of ShCYP51B and ShatrD in isolates from two golf courses that exhibited practical field resistance to propiconazole uncovered evidence for significant population-specific overexpression of both genes. However, linear regression demonstrated that the RE of ShatrD displays a more significant relationship with propiconazole sensitivity than that of ShCYP51B. In summary, our results suggest that efflux is a major determinant of the reduced DMI sensitivity of S. homoeocarpa genotypes in New England, which may have implications for the emergence of practical field resistance in this important turfgrass pathogen.

  17. High-Mannose Specific Lectin and Its Recombinants from a Carrageenophyta Kappaphycus alvarezii Represent a Potent Anti-HIV Activity Through High-Affinity Binding to the Viral Envelope Glycoprotein gp120.

    Science.gov (United States)

    Hirayama, Makoto; Shibata, Hiromi; Imamura, Koji; Sakaguchi, Takemasa; Hori, Kanji

    2016-04-01

    We previously reported that a high-mannose binding lectin KAA-2 from the red alga Kappaphycus alvarezii, which is an economically important species and widely cultivated as a source of carrageenans, had a potent anti-influenza virus activity. In this study, the full-length sequences of two KAA isoforms, KAA-1 and KAA-2, were elucidated by a combination of peptide mapping and cDNA cloning. They consisted of four internal tandem-repeated domains, which are conserved in high-mannose specific lectins from lower organisms, including a cyanobacterium Oscillatoria agardhii and a red alga Eucheuma serra. Using an Escherichia coli expression system, an active recombinant form of KAA-1 (His-tagged rKAA-1) was successfully generated in the yield of 115 mg per a litter of culture. In a detailed oligosaccharide binding analysis by a centrifugal ultrafiltration-HPLC method with 27 pyridylaminated oligosaccharides, His-tagged rKAA-1 and rKAA-1 specifically bound to high-mannose N-glycans with an exposed α1-3 mannose in the D2 arm as the native lectin did. Predicted from oligosaccharide-binding specificity, a surface plasmon resonance analysis revealed that the recombinants exhibit strong interaction with gp120, a heavily glycosylated envelope glycoprotein of HIV with high association constants (1.48-1.61 × 10(9) M(-1)). Native KAAs and the recombinants inhibited the HIV-1 entry at IC50s of low nanomolar levels (7.3-12.9 nM). Thus, the recombinant proteins would be useful as antiviral reagents targeting the viral surface glycoproteins with high-mannose N-glycans, and the cultivated alga K. alvarezii could also be a good source of not only carrageenans but also this functional lectin(s).

  18. VT Biodiversity Project - Representative Landscapes boundary lines

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This coverage represents the results of an analysis of landscape diversity in Vermont. Polygons in the dataset represent as much as possible (in a...

  19. Representing Uncertainty by Probability and Possibility

    DEFF Research Database (Denmark)

    Uncertain parameters in modeling are usually represented by probability distributions reflecting either the objective uncertainty of the parameters or the subjective belief held by the model builder. This approach is particularly suited for representing the statistical nature or variance of uncer......Uncertain parameters in modeling are usually represented by probability distributions reflecting either the objective uncertainty of the parameters or the subjective belief held by the model builder. This approach is particularly suited for representing the statistical nature or variance...

  20. Representing Uncertainty by Probability and Possibility

    DEFF Research Database (Denmark)

    Uncertain parameters in modeling are usually represented by probability distributions reflecting either the objective uncertainty of the parameters or the subjective belief held by the model builder. This approach is particularly suited for representing the statistical nature or variance of uncer......Uncertain parameters in modeling are usually represented by probability distributions reflecting either the objective uncertainty of the parameters or the subjective belief held by the model builder. This approach is particularly suited for representing the statistical nature or variance...

  1. 7 CFR 1280.611 - Representative period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Representative period. 1280.611 Section 1280.611... INFORMATION ORDER Procedures To Request a Referendum Definitions § 1280.611 Representative period. Representative period means the period designated by the Secretary pursuant to § 518 of the Act. ...

  2. 29 CFR 548.405 - Representative period.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Representative period. 548.405 Section 548.405 Labor... Application § 548.405 Representative period. (a) The application must set forth the facts relied upon to show... employee exclusive of overtime premiums over a representative period of time. 21 The basic rate will be...

  3. 7 CFR 1230.618 - Representative period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Representative period. 1230.618 Section 1230.618... CONSUMER INFORMATION Procedures for the Conduct of Referendum Definitions § 1230.618 Representative period. The term Representative period means the 12-consecutive months prior to the first day of absentee and...

  4. 7 CFR 1220.612 - Representative period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Representative period. 1220.612 Section 1220.612... CONSUMER INFORMATION Procedures To Request a Referendum Definitions § 1220.612 Representative period. Representative period means the period designated by the Secretary pursuant to section 1970 of the Act. ...

  5. Adsorption behavior of representative phenolic endocrine disrupting chemicals on activated carbons%典型酚类内分泌干扰物的活性炭吸附行为

    Institute of Scientific and Technical Information of China (English)

    刘桂芳; 马军; 任芝军; 朱丽楠; 米海蓉; 官涤

    2011-01-01

    Aqueous adsorption behavior of six phenolic endocrine disrupting chemicals (EDCs) on two powdered activated carbons (WP and WPN) was investigated through static adsorption experiment. The results indicated that the adsorption processes of all six EDCs agreed well with the pseudo-second-order kinetic model. The adsorption capacity of nonylphenol on WP and WPN was the highest, with equilibrium adsorption amount (qe) 6 535.95 μmol · g-1 and 7 246. 38 μ mol· g-1, respectively, followed by estrone. The adsorption capacity of estradiol was the poorest, which reached 1 636. 66 μmol · g-1 and 1 801.80 μmol · g-1 on WP and WPN, respectively. Furthermore, the adsorption capacities of target compounds had a positive correlation with their octanol/water distribution coefficient as their initial aqueous concentration was equal. And, the modified carbon sample WPN showed better adsorption capacity. Compared with that on the original sample WP, the qe of six EDCs was increased by 2. 5% ~ 63.6% on WPN. Thus, purification ability of activated carbon could be improved by some certain modification treatment when used to treat such like compounds in practice.%在静态吸附实验中,考察了水中六种酚类内分泌干扰物(EDCs)在两种粉末活性炭(WP和WPN)上的吸附行为.结果表明,六种EDCs在活性炭上的吸附过程均为假二级动力学吸附,其中壬基酚(4-n-NP)在WP和WPN上表现出最高的吸附能力,平衡吸附量(qe)分别达到了6 535.95μmol·g-1与7 246.38μmol·g-1,其次是雌激素酮(E1),吸附能力最差的是雌二醇(E2),qe值仅为1 636.66μmol·g-1与1 801.80 μmol·g-1.进一步研究结果表明,初始浓度相同时,目标物在活性炭上的吸附能力与其正辛醇/水分配系数(1ogKOW)正相关,并且改性炭WPN对六种EDCs表现出相对更高的平衡吸附量,较原炭WP的平衡吸附量提高了2.5%~63.6%,因此,在活性炭实际应用前可通过一定改性处理方法提高其对水中该类污染物的净化能力.

  6. Mining Representative Subset Based on Fuzzy Clustering

    Institute of Scientific and Technical Information of China (English)

    ZHOU Hongfang; FENG Boqin; L(U) Lintao

    2007-01-01

    Two new concepts-fuzzy mutuality and average fuzzy entropy are presented. Then based on these concepts, a new algorithm-RSMA (representative subset mining algorithm) is proposed, which can abstract representative subset from massive data.To accelerate the speed of producing representative subset, an improved algorithm-ARSMA(accelerated representative subset mining algorithm) is advanced, which adopt combining putting forward with backward strategies. In this way, the performance of the algorithm is improved. Finally we make experiments on real datasets and evaluate the representative subset. The experiment shows that ARSMA algorithm is more excellent than RandomPick algorithm either on effectiveness or efficiency.

  7. Cytoplasmic localization of wild-type survivin is associated with constitutive activation of the PI3K/Akt signaling pathway and represents a favorable prognostic factor in patients with acute myeloid leukemia.

    Science.gov (United States)

    Serrano-López, Juana; Serrano, Josefina; Figueroa, Vianihuini; Torres-Gomez, Antonio; Tabares, Salvador; Casaño, Javier; Fernandez-Escalada, Noemi; Sánchez-Garcia, Joaquín

    2013-12-01

    Survivin is over-expressed in most hematologic malignancies but the prognostic significance of the subcompartmental distribution of wild-type or splicing variants in acute myeloid leukemia has not been addressed yet. Using western blotting, we assessed the expression of wild-type survivin and survivin splice variants 2B and Delta-Ex3 in nuclear and cytoplasmic protein extracts in samples taken from 105 patients at the time of their diagnosis of acute myeloid leukemia. Given that survivin is a downstream effector of the PI3K/Akt signaling pathway, survivin expression was also correlated with pSer473-Akt. Wild-type survivin and the 2B splice variant were positive in 76.3% and 78.0% of samples in the nucleus, cytoplasm or both, whereas the Delta-Ex3 isoform was only positive in the nucleus in 37.7% of samples. Cytoplasmic localization of wild-type survivin was significantly associated with the presence of high levels of pSer473-Akt (P<0.001). Inhibition of the PI3K/Akt pathway with wortmannin and Ly294002 caused a significant reduction in the expression of cytoplasmic wild-type survivin. The presence of cytoplasmic wild-type survivin and pSer473-Akt was associated with a lower fraction of quiescent leukemia stem cells (P=0.02). The presence of cytoplasmic wild-type survivin and pSer473-Akt were favorable independent prognostic factors. Moreover, the activation of the PI3K/Akt pathway with expression of cytoplasmic wild-type survivin identified a subgroup of acute myeloid leukemia patients with an excellent outcome (overall survival rate of 60.0±21.9% and relapse-free survival of 63.0±13.5%). Our findings suggest that cytoplasmic wild-type survivin is a critical downstream effector of the PI3K/Akt pathway leading to more chemosensitive cells and a more favorable outcome in acute myeloid leukemia.

  8. Physical activity and screen-based media use: cross-sectional associations with health-related quality of life and the role of body satisfaction in a representative sample of German adolescents.

    Science.gov (United States)

    Finne, Emily; Bucksch, Jens; Lampert, Thomas; Kolip, Petra

    2013-01-01

    Purpose: Although it is widely accepted that physical activity (PA) positively, and screen-based media use (SBM) negatively, affects well-being, there is a lack of studies relating PA and SBM to health-related quality of life (HRQoL) in adolescents. We examined these associations in German adolescents for different HRQoL subdomains and explored the role of body satisfaction as a possible mediator. Methods: The 11-17-year-old subsample of the German Health Interview and Examination Survey (2003-2006) was analysed (N = 6813; 51.3% male). Cross-sectional associations of self-reported PA frequency and amount of daily SBM with HRQoL subscale scores (according to KINDL-R) were examined by hierarchical linear regression models, adjusting for the clustering of the sample and for a variety of possible confounders. The size and significance of indirect effects via body (dis)satisfaction (BDS) were examined by mediation analyses. Results: Higher PA frequency was significantly associated with higher HRQoL on nearly all subscales and dose-response-relationships were observable. Variations were greatest in terms of social well-being in boys (effect size d = 0.59) and physical well-being in girls (d = 0.43). Higher SBM was related to lower HRQoL on all subscales in girls and on some subscales in boys, with the largest effects for school functioning in both genders (d = 0.31 and 0.37, respectively). The mediated effects for PA and SBM were significant in both genders, but the sizes and the proportions of total effects mediated by body satisfaction were rather small. Conclusions: Higher PA frequency was associated with higher self-reported HRQoL, and higher SBM was associated with lower self-reported HRQoL in both genders, even after adjusting for relevant covariates. The results support the assumption of independent health impacts of both behaviours, although no causal relationship can be confirmed with these cross-sectional data. Mechanisms other than body satisfaction must

  9. Comparing German and Danish employee representatives on European Works Councils

    DEFF Research Database (Denmark)

    Bicknell, Helen; Knudsen, Herman Lyhne

    2006-01-01

    This article aims to analyse the links and possible‘fit’ between German and Danish representation structures and trade union policies on the one hand, and the views and activities of European Works Council (EWC) representatives from the two countries on the other. Which similarities or differences....... It is concluded that the views and practices of German and Danish EWC representatives largely converge. Those divergent views that are found are explained by differences in national representation structures, union policies and labour market situation....

  10. Representing Others in a Public Good Game

    Directory of Open Access Journals (Sweden)

    Karen Evelyn Hauge

    2015-09-01

    Full Text Available In many important public good situations the decision-making power and authority is delegated to representatives who make binding decisions on behalf of a larger group. The purpose of this study is to compare contribution decisions made by individuals with contribution decisions made by group representatives. We present the results from a laboratory experiment that compares decisions made by individuals in inter-individual public good games with decisions made by representatives on behalf of their group in inter-group public good games. Our main finding is that contribution behavior differs between individuals and group representatives, but only for women. While men’s choices are equally self-interested as individuals and group representatives, women make less self-interested choices as group representatives.

  11. Represented Speech in Qualitative Health Research

    DEFF Research Database (Denmark)

    Musaeus, Peter

    2017-01-01

    Represented speech refers to speech where we reference somebody. Represented speech is an important phenomenon in everyday conversation, health care communication, and qualitative research. This case will draw first from a case study on physicians’ workplace learning and second from a case study...... on nurses’ apprenticeship learning. The aim of the case is to guide the qualitative researcher to use own and others’ voices in the interview and to be sensitive to represented speech in everyday conversation. Moreover, reported speech matters to health professionals who aim to represent the voice...... of their patients. Qualitative researchers and students might learn to encourage interviewees to elaborate different voices or perspectives. Qualitative researchers working with natural speech might pay attention to how people talk and use represented speech. Finally, represented speech might be relevant...

  12. Representing Quadric Surfaces Using NURBS Surfaces

    Institute of Scientific and Technical Information of China (English)

    秦开怀

    1997-01-01

    A method for representing quadrc surfaces using NURBS is presented.By means of the necessary and sufficient conditons for NURBS curves to precisely represent circular arcs and other conics,quadric surfaces can be represented by NURBS surfaces with fewer control vertices.The method can be used not only for NURBS surface representation of quadric surfaces,but also for rounding polyhedrons.Many examples are given in the paper.

  13. Regulation of demethylation and re-expression of RASSF1A gene in hepatocellular carcinoma cell lines treated with NCTD in vitro

    Directory of Open Access Journals (Sweden)

    Yong Wang

    2015-01-01

    Full Text Available Background: Hepatocellular carcinoma, a lethal malignant neoplasm with poor prognosis, has dismal results of surgical resection and chemoradiotherapy. Norcantharidin (NCTD, the demethylated analog of cantharidin derived from a traditional Chinese medicine, Mylabris, has been used in the treatment of cancer. However, the detailed mechanisms underlying this process are generally unclear. Purpose: The aim of this study was to investigate the mechanism of NCTD-induced apoptosis in HepG2 cells. Materials and Methods: Human HepG2 cell lines were treated with NCTD at different concentrations (2.50, 5.00, 10.00, 20.00, 40.00 μg/mL for 24 hours. Cell proliferation was evaluated by measurement of cellular 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT. The methylation levels of RASSF1A (Ras-association domain family 1 A in HepG2 cells were detected by methylation-specific PCR (MSP. The mRNA levels of RASSF1A in HepG2 cells were detected by real-time fluorescent quantitative PCR (RT-PCR. The levels of RASSF1A protein expression of HepG2 cells were detected by Western blotting assay. Results: The inhibition of cell proliferation was observed when treated with NCTD at concentrations (2.5 μg/mL, and as concentration increased, the proliferation of HepG2 cells was markedly inhibited by NCTD in dose-dependent manners. The levels of methylation of RASSF1A decreased at the increasing concentration of 10, 20 and 40 μg/mL. The levels of RASSF1A mRNA and protein were decreased when treated with NCTD at the concentrations of 10, 20 and 40 μg/mL, which were also in a dose-dependent manner. Conclusion: NCTD can reverse the methylation state of RASSF1A gene and induce its re-expression, which will provide the theoretical basis for the clinical practice.

  14. [Temporal lobe epilepsy and active neurocysticercosis: two representative case reports].

    Science.gov (United States)

    Ramos-Zúñiga, Rodrigo; Pérez-Gómez, Héctor R; Gaytán-Martínez, Luis A; Vega-Ruiz, Brenda; Soto-Rodríguez, Sofía; Rochín-Mozqueda, Alejandro

    2015-01-01

    Introduccion. Existen pocas evidencias notificadas de casos de epilepsia del lobulo temporal asociadas a cisticercosis activa en su fase quistica. El objetivo es presentar la correlacion entre cisticercosis activa en zonas topograficas asociadas a epilepsia del lobulo temporal, con las manifestaciones neuropsiquiatricas y el patron de crisis parciales secundariamente generalizadas. Casos clinicos. Dos casos de pacientes adultos con manifestaciones neuropsiquiatricas de un año de evolucion, refractarios a tratamiento farmacologico antipsicotico, y en quienes posteriormente aparecen crisis convulsivas parciales secundariamente generalizadas de inicio tardio. Se identifica la presencia de cisticercosis activa en el lobulo temporal en un paciente, y en la insula, en el otro. Buen control clinico posterior al tratamiento con albendazol, pero se mantiene el mismo tratamiento anticonvulsionante para considerar la pertinencia de su retirada farmacologica. Conclusiones. La neurocisticercosis activa puede ser causa de trastornos neuropsiquiatricos adquiridos y de epilepsia del lobulo temporal de inicio tardio cuando su topografia se encuentra en el circuito mesolimbico. El diagnostico etiologico oportuno y el tratamiento apropiado permiten el control adecuado de su sintomatologia y, potencialmente, su curacion definitiva.

  15. Think tank (3) - Present activities of other representative organizations

    Science.gov (United States)

    Obara, Michio

    There were some think tank businesses in Japan before the war. South Manchuria Railway Company established its Research Department for the purpose of getting power to control Manchuria as a colony, and got the good results. Think tank business was flourishing three times after the war. This business attracts much attention when the social and economic paradigm is going to change. Among the key large-scale think tanks in Japan, Nomura Research Institute, Ltd. (NRI) was the first to enhance the system functions by the merger, and posted think tank function up in the SI business. Mitsubishi Research Institute, Inc. (MRI) intends to be an orthodox think tank, and established an advanced research institute and the laboratory for R&D. Daiwa Institute of Research, Ltd. (DIR) focuses on economic forecast by using system. Fuji Research Institute, Corp. (FUJI RIC) focuses on survey and policy proposing in macro-economics, and analyzing technology. The Japan Research Institute, Ltd. (JRI) focuses on regional development, and R&D in advanced technology.

  16. Representing Object Colour in Language Comprehension

    Science.gov (United States)

    Connell, Louise

    2007-01-01

    Embodied theories of cognition hold that mentally representing something "red" engages the neural subsystems that respond to environmental perception of that colour. This paper examines whether implicit perceptual information on object colour is represented during sentence comprehension even though doing so does not necessarily facilitate task…

  17. Automated extraction of lysergic acid diethylamide (LSD) and N-demethyl-LSD from blood, serum, plasma, and urine samples using the Zymark RapidTrace with LC/MS/MS confirmation.

    Science.gov (United States)

    de Kanel, J; Vickery, W E; Waldner, B; Monahan, R M; Diamond, F X

    1998-05-01

    A forensic procedure for the quantitative confirmation of lysergic acid diethylamide (LSD) and the qualitative confirmation of its metabolite, N-demethyl-LSD, in blood, serum, plasma, and urine samples is presented. The Zymark RapidTrace was used to perform fully automated solid-phase extractions of all specimen types. After extract evaporation, confirmations were performed using liquid chromatography (LC) followed by positive electrospray ionization (ESI+) mass spectrometry/mass spectrometry (MS/MS) without derivatization. Quantitation of LSD was accomplished using LSD-d3 as an internal standard. The limit of quantitation (LOQ) for LSD was 0.05 ng/mL. The limit of detection (LOD) for both LSD and N-demethyl-LSD was 0.025 ng/mL. The recovery of LSD was greater than 95% at levels of 0.1 ng/mL and 2.0 ng/mL. For LSD at 1.0 ng/mL, the within-run and between-run (different day) relative standard deviation (RSD) was 2.2% and 4.4%, respectively.

  18. 7 CFR 1205.20 - Representative period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Representative period. 1205.20 Section 1205.20 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING... period means the 2006 calendar year....

  19. Enhancing policy innovation by redesigning representative democracy

    DEFF Research Database (Denmark)

    Sørensen, Eva

    2016-01-01

    . Two Danish case studies indicate that collaboration between politicians and relevant and affected stakeholders can promote policy innovation, but also that a redesign of representative democracy is needed in order to establish a productive combination of political leadership, competition...

  20. REFractions: The Representing Equivalent Fractions Game

    Science.gov (United States)

    Tucker, Stephen I.

    2014-01-01

    Stephen Tucker presents a fractions game that addresses a range of fraction concepts including equivalence and computation. The REFractions game also improves students' fluency with representing, comparing and adding fractions.

  1. Caspar Wessel on representing complex numbers (1799)

    DEFF Research Database (Denmark)

    Branner, Bodil

    1999-01-01

    In celebration of the bicentenary of the publication of Wessel's paper on the geometric interpretation of complex numbers it is decsribed how Wessel used complex numbers to represent directions in surveying, at least as early as 1787.......In celebration of the bicentenary of the publication of Wessel's paper on the geometric interpretation of complex numbers it is decsribed how Wessel used complex numbers to represent directions in surveying, at least as early as 1787....

  2. Union Learning Representatives: Facilitating Professional Development for Scottish Teachers

    Science.gov (United States)

    Alexandrou, Alex; O'Brien, Jim

    2007-01-01

    In the United Kingdom, teachers' professional associations and labor organizations, notably in the form of trade unions have historically been involved in education and training in the workplace. Recently, in the United Kingdom this activity has gained greater credence and importance due to the emergence of trade union learning representatives who…

  3. Quadratic forms representing all odd positive integers

    CERN Document Server

    Rouse, Jeremy

    2011-01-01

    We consider the problem of classifying all positive-definite integer-valued quadratic forms that represent all positive odd integers. Kaplansky considered this problem for ternary forms, giving a list of 23 candidates, and proving that 19 of those represent all positive odds. (Jagy later dealt with a 20th candidate.) Assuming that the remaining three forms represent all positive odds, we prove that an arbitrary, positive-definite quadratic form represents all positive odds if and only if it represents the odd numbers from 1 up to 451. This result is analogous to Bhargava and Hanke's celebrated 290-theorem. In addition, we prove that these three remaining ternaries represent all positive odd integers, assuming the generalized Riemann hypothesis. This result is made possible by a new analytic method for bounding the cusp constants of integer-valued quaternary quadratic forms $Q$ with fundamental discriminant. This method is based on the analytic properties of Rankin-Selberg $L$-functions, and we use it to prove...

  4. Do regional climate models represent regional climate?

    Science.gov (United States)

    Maraun, Douglas; Widmann, Martin

    2014-05-01

    When using climate change scenarios - either from global climate models or further downscaled - to assess localised real world impacts, one has to ensure that the local simulation indeed correctly represents the real world local climate. Representativeness has so far mainly been discussed as a scale issue: simulated meteorological variables in general represent grid box averages, whereas real weather is often expressed by means of point values. As a result, in particular simulated extreme values are not directly comparable with observed local extreme values. Here we argue that the issue of representativeness is more general. To illustrate this point, assume the following situations: first, the (GCM or RCM) simulated large scale weather, e.g., the mid-latitude storm track, might be systematically distorted compared to observed weather. If such a distortion at the synoptic scale is strong, the simulated local climate might be completely different from the observed. Second, the orography even of high resolution RCMs is only a coarse model of true orography. In particular in mountain ranges the simulated mesoscale flow might therefore considerably deviate from the observed flow, leading to systematically displaced local weather. In both cases, the simulated local climate does not represent observed local climate. Thus, representativeness also encompasses representing a particular location. We propose to measure this aspect of representativeness for RCMs driven with perfect boundary conditions as the correlation between observations and simulations at the inter-annual scale. In doing so, random variability generated by the RCMs is largely averaged out. As an example, we assess how well KNMIs RACMO2 RCM at 25km horizontal resolution represents winter precipitation in the gridded E-OBS data set over the European domain. At a chosen grid box, RCM precipitation might not be representative of observed precipitation, in particular in the rain shadow of major moutain ranges

  5. Representative Democracy in Australian Local Government

    Directory of Open Access Journals (Sweden)

    Colin Hearfield

    2009-01-01

    Full Text Available In an assessment of representative democracy in Australian local government, this paper considers long-run changes in forms of political representation, methods of vote counting, franchise arrangements, numbers of local government bodies and elected representatives, as well as the thorny question of constitutional recognition. This discussion is set against the background of ongoing tensions between the drive for economic efficiency and the maintenance of political legitimacy, along with more deep-seated divisions emerging from the legal relationship between local and state governments and the resultant problems inherent in local government autonomy versus state intervention.

  6. Representative Sampling for reliable data analysis

    DEFF Research Database (Denmark)

    Petersen, Lars; Esbensen, Kim Harry

    2005-01-01

    The Theory of Sampling (TOS) provides a description of all errors involved in sampling of heterogeneous materials as well as all necessary tools for their evaluation, elimination and/or minimization. This tutorial elaborates on—and illustrates—selected central aspects of TOS. The theoretical...... regime in order to secure the necessary reliability of: samples (which must be representative, from the primary sampling onwards), analysis (which will not mean anything outside the miniscule analytical volume without representativity ruling all mass reductions involved, also in the laboratory) and data...

  7. Representing uncertainty on model analysis plots

    Science.gov (United States)

    Smith, Trevor I.

    2016-12-01

    Model analysis provides a mechanism for representing student learning as measured by standard multiple-choice surveys. The model plot contains information regarding both how likely students in a particular class are to choose the correct answer and how likely they are to choose an answer consistent with a well-documented conceptual model. Unfortunately, Bao's original presentation of the model plot did not include a way to represent uncertainty in these measurements. I present details of a method to add error bars to model plots by expanding the work of Sommer and Lindell. I also provide a template for generating model plots with error bars.

  8. Representative Sampling for reliable data analysis

    DEFF Research Database (Denmark)

    Petersen, Lars; Esbensen, Kim Harry

    2005-01-01

    regime in order to secure the necessary reliability of: samples (which must be representative, from the primary sampling onwards), analysis (which will not mean anything outside the miniscule analytical volume without representativity ruling all mass reductions involved, also in the laboratory) and data...... analysis (“data” do not exist in isolation of their provenance). The Total Sampling Error (TSE) is by far the dominating contribution to all analytical endeavours, often 100+ times larger than the Total Analytical Error (TAE).We present a summarizing set of only seven Sampling Unit Operations (SUOs...

  9. Regulation of demethylation and re-expression of RASSF1A gene in gastric cancer cell lines by combined treatment of 5-Aza-CdR and NaB

    Institute of Scientific and Technical Information of China (English)

    Wen-Jing Shen; Dong-Qiu Dai; Yue Teng; Hong-Bo Liu

    2008-01-01

    AIM: To investigate the changes of methylation state and expression of RASSF1A gene in human gastric cancer cell lines SGC7901 and BGC823 which were treated in vitro with demethlylating agent 5-Aza-CdR in combination with histone deacetylase inhibitor NaB.METHODS: After SGC7901 and BGC823 cells were treated with 5-Aza-CdR and/or NaB, the methylation state of RASSF1A gene was detected by methylation-specific PCR, and the changes in expression of mRNA and protein level of RASSF1A gene were observed by RT-PCR and Western-blotting before and after drug treatment.RESULTS: Hypermethylation was detected in the promoter region of RASSF1A gene in both SGC7901 and BGC823 cells, and there was no expression of this gene at both mRNA and protein level. After treatment with 5-Aza-CdR, demethylation occurred in the promoter region of RASSF1A gene, which subsequently induced re-expression of this gene. The treatment with NaB alone showed no effect on the methylation state and expression of RASSF1A gene. The combined treatment of 5-Aza-CdR and NaB induced complete demethylation of RASSF1A gene, leading to a significantly higher re-expression of the mRNA and protein of RASSF1A than those treated with 5-Aza-CdR alone (P < 0.05).CONCLUSION: Hypermethylation in the promoter region is related to inactivation of RASSF1A gene in human gastric cancer cell lines SGC7901 and BGC823, while demethlylating agent 5-Aza-CdR can reverse the methylation state of RASSF1A gene and induce itsre-expression. Histone deacetylase inhibitor NaB had a synergistic effect with 5-Aza-CdR in both demethylation and gene transcriptional regulation.(c) 2008 WJG. All rights reserved.

  10. Relationship of the demethylation of the DNA with the induction of the sister chromatid exchanges (SCE) In vivo; Relacion de la desmetilacion del ADN con la induccion de intercambios en las cromatidas hermanas (ICH) In vivo

    Energy Technology Data Exchange (ETDEWEB)

    Toribio E, E

    2005-07-01

    The methylation of the DNA is an epigenetic modification that has an important paper in the regulation of the functionality of the genome of the organisms. It can be altered by demethylation processes, either natural or experimentally induced. The 5-azacytidine (Aza) is a compound that causes the demethylation of the DNA (dm-DNA), inducing with it, expression genic and increase in the frequency of the Sister Chromatid Exchange (SCE). The SCE is a genotoxicity indicator, caused by diverse mutagens and carcinogen. Since the biological meaning and the formation mechanism of this phenomenon has not been totally illustrious, the exploration of the relation between the dm-DNA and the induction of SCE, it could offer new knowledge to explain those queries. The purpose of this work was to study in cells of the mouse bone marrow In vivo, the effect of the Aza on the induction of SCE, based on two aspects: 1) dose answer and 2) the effectiveness of multiple exhibition. To six groups of three to five animals, they are administered Aza to dose of 5, 10, 15 or 20 mg/Kg of weight; in sharp or multiple form, previously to the bromodeoxyuridine supply and 24 h was sacrificed after this; 2 h after an injection with colchicine. Preparations of those metaphases were made, those which were dyed by means of a technique of fluorescence more Giemsa. It was observed that to sharp low dose, the Aza produced an increment in the frequency of SCE that although small it was proportional and statistically significant. To sharp and multiple high doses, the Aza doesn't cause additional increments of SCE, but if toxicity at cellular level and of individuals. It is concluded that a relationship exists between the dm-DNA and the induction of SCE. It is suggested that the total demethylation of the DNA causes 2 SCE/Cell in cells of the mouse bone marrow, or that the cytotoxicity prevents to evidence a bigger induction. (Author)

  11. Attributes Heeded When Representing an Osmosis Problem.

    Science.gov (United States)

    Zuckerman, June Trop

    Eighteen high school science students were involved in a study to determine what attributes in the problem statement they need when representing a typical osmosis problem. In order to realize this goal students were asked to solve problems aloud and to explain their answers. Included as a part of the results are the attributes that the students…

  12. A Framework for Representing Moving Objects

    DEFF Research Database (Denmark)

    Becker, Ludger; Blunck, Henrik; Hinrichs, Klaus

    2004-01-01

    We present a framework for representing the trajectories of moving objects and the time-varying results of operations on moving objects. This framework supports the realization of discrete data models of moving objects databases, which incorporate representations of moving objects based on non-li...

  13. Developing Creativity and Abstraction in Representing Data

    Science.gov (United States)

    South, Andy

    2012-01-01

    Creating charts and graphs is all about visual abstraction: the process of representing aspects of data with imagery that can be interpreted by the reader. Children may need help making the link between the "real" and the image. This abstraction can be achieved using symbols, size, colour and position. Where the representation is close to what…

  14. Studies of H3K4me3 demethylation by KDM5B/Jarid1B/PLU1 reveals strong substrate recognition in vitro and identifies 2,4-pyridine-dicarboxylic acid as an in vitro and in cell inhibitor

    DEFF Research Database (Denmark)

    Kristensen, Line Hyltoft; Nielsen, Anders Laerke; Helgstrand, Charlotte

    2012-01-01

    Dynamic methylations and demethylations of histone lysine residues are important for gene regulation and are facilitated by histone methyltransferases and histone demethylases (HDMs). KDM5B/Jarid1B/PLU1 is an H3K4me3/me2 specific lysine demethylase belonging to the family of JmjC domain containin...

  15. Representative parameter of immunostimulatory ginseng polysaccharide to predict radioprotection

    Energy Technology Data Exchange (ETDEWEB)

    Son, Hyeog Jin; Shim, Ji Young; Ahn, Ji Yeon; Yun, Yeon Sook; Song, Jie Young [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2008-09-15

    According to the increase in the use of radiotherapy to cancer patients, many approaches have been tried to develop new agents for the protection of surrounding normal tissues. However, it is still few applied in the clinic as a radioprotector. We aim to find a representative parameter for radioprotection to easily predict the activity of in vivo experiment from the results of in vitro screening. The polysaccharide extracted from Panax ginseng was used in this study because the immunostimulator has been regarded as one of the radioprotective agent category and was already reported having a promising radioprotective activity through the increase of hematopoietic cells and the production of several cytokines. Mitogenic activity, AK cells activity and nitric oxide production were monitored for the in vitro immunological assay, and endogenous Colony-Forming Unit (e-CFU) was measured as in vivo radioprotective parameter. The immunological activity was increased by the galactose contents of ginseng polysaccharide dependently. The result of this study suggests that mitogenic activity of splenocytes demonstrated a good correlation with in vivo radioprotective effect, and may be used as a representative parameter to screen the candidates for radioprotector.

  16. Climate Change and the Representative Agent

    Energy Technology Data Exchange (ETDEWEB)

    Howarth, R.B. [Environmental Studies Program, Dartmouth College, Hanover, New Hampshire 03755 (United States)

    2000-02-01

    The artifice of an infinitely-lived representative agent is commonly invoked to balance the present costs and future benefits of climate stabilization policies. Since actual economies are populated by overlapping generations of finite-lived persons, this approach begs important questions of welfare aggregation. This paper compares the results of representative agent and overlapping generations models that are numerically calibrated based on standard assumptions regarding climate economy interactions. Under two social choice rules - Pareto efficiency and classical utilitarianism - the models generate closely similar simulation results. In the absence of policies to redistribute income between present and future generations, efficient rates of carbon dioxide emissions abatement rise from 15 to 20% between the years 2000 and 2105. Under classical utilitarianism, in contrast, optimal control rates rise from 48 to 79% this same period. 23 refs.

  17. Representing Boolean Functions by Decision Trees

    KAUST Repository

    Chikalov, Igor

    2011-01-01

    A Boolean or discrete function can be represented by a decision tree. A compact form of decision tree named binary decision diagram or branching program is widely known in logic design [2, 40]. This representation is equivalent to other forms, and in some cases it is more compact than values table or even the formula [44]. Representing a function in the form of decision tree allows applying graph algorithms for various transformations [10]. Decision trees and branching programs are used for effective hardware [15] and software [5] implementation of functions. For the implementation to be effective, the function representation should have minimal time and space complexity. The average depth of decision tree characterizes the expected computing time, and the number of nodes in branching program characterizes the number of functional elements required for implementation. Often these two criteria are incompatible, i.e. there is no solution that is optimal on both time and space complexity. © Springer-Verlag Berlin Heidelberg 2011.

  18. Data structures and apparatuses for representing knowledge

    Science.gov (United States)

    Hohimer, Ryan E; Thomson, Judi R; Harvey, William J; Paulson, Patrick R; Whiting, Mark A; Tratz, Stephen C; Chappell, Alan R; Butner, Robert S

    2014-02-18

    Data structures and apparatuses to represent knowledge are disclosed. The processes can comprise labeling elements in a knowledge signature according to concepts in an ontology and populating the elements with confidence values. The data structures can comprise knowledge signatures stored on computer-readable media. The knowledge signatures comprise a matrix structure having elements labeled according to concepts in an ontology, wherein the value of the element represents a confidence that the concept is present in an information space. The apparatus can comprise a knowledge representation unit having at least one ontology stored on a computer-readable medium, at least one data-receiving device, and a processor configured to generate knowledge signatures by comparing datasets obtained by the data-receiving devices to the ontologies.

  19. Representing a public that does not exist

    DEFF Research Database (Denmark)

    Korsgaard, Morten Timmermann

    and function of the teacher. Confronted by this teachers and educationalists in Denmark have chosen different paths. One current returns to nationalistic and traditional educational ideals and another accepts the global agenda and attempts to find a new form of legitimacy within the ‘what works’ framework......In her seminal essay ‘The Crisis in Education’ Hannah Arendt presents teachers with the challenge of having to represent a world that is becoming out of joint. This means that the teacher stands as a representative of a world that is becoming increasingly inexplicable and incomprehensible......, and the only way of retaining any form of authority (and legitimacy as a teacher) is to remain loyal to the task of presenting this world to the child. This challenge presents itself acutely in the form of a global reform agenda that legitimizes standardisation and accountability while eroding the authority...

  20. Can Monkeys (Macaca mulatta) Represent Invisible Displacement?

    Science.gov (United States)

    Filion, Christine M.; Washburn, David A.; Gulledge, Jonathan P.

    1996-01-01

    Four experiments were conducted to assess whether or not rhesus macaques (Macaca mulatta) could represent the unperceived movements of a stimulus. Subjects were tested on 2 computerized tasks, HOLE (monkeys) and LASER (humans and monkeys), in which subjects needed to chase or shoot at, respectively, a moving target that either remained visible or became invisible for a portion of its path of movement. Response patterns were analyzed and compared between target-visible and target-invisible conditions. Results of Experiments 1, 2, and 3 demonstrated that the monkeys are capable of extrapolating movement. That this extrapolation involved internal representation of the target's invisible movement was suggested but not confirmed. Experiment 4, however, demonstrated that the monkeys are capable of representing the invisible displacements of a stimulus.

  1. Representing exact number visually using mental abacus.

    Science.gov (United States)

    Frank, Michael C; Barner, David

    2012-02-01

    Mental abacus (MA) is a system for performing rapid and precise arithmetic by manipulating a mental representation of an abacus, a physical calculation device. Previous work has speculated that MA is based on visual imagery, suggesting that it might be a method of representing exact number nonlinguistically, but given the limitations on visual working memory, it is unknown how MA structures could be stored. We investigated the structure of the representations underlying MA in a group of children in India. Our results suggest that MA is represented in visual working memory by splitting the abacus into a series of columns, each of which is independently stored as a unit with its own detailed substructure. In addition, we show that the computations of practiced MA users (but not those of control participants) are relatively insensitive to verbal interference, consistent with the hypothesis that MA is a nonlinguistic format for exact numerical computation.

  2. Representativeness and significance factors in ESP texts

    Directory of Open Access Journals (Sweden)

    Alejandro Curado Fuentes

    2000-04-01

    Full Text Available The development of communicative approaches and strategies in specialized discourse has led to revising notions of representative and significant language . Particularly in the work with academic genres, in science and technology (EST settings such as our own institution, the need for determining these factors is ever growing. The application of empirical resources such as specific language corpora, in fact, becomes convenient. In this paper, the aim is to specify the type of corpus linguistic representativeness and significance sought in the case of teaching English to our groups of Computer Science students. In that scope, we present data and samples on which to base our suggestions and claims regarding the exploitation of textual material.

  3. Meeting staff representatives of the European Agencies

    CERN Multimedia

    Staff Association

    2014-01-01

      The AASC (Assembly of Agency Staff Committee) held its 27th Meeting of the specialized European Agencies on 26 and 27 May on the premises of the OHIM (Office for Harmonization in the Internal Market) in Alicante, Spain. Two representatives of the CERN Staff Association, in charge of External Relations, attended as observers. This participation is a useful complement to regular contacts we have with FICSA (Federation of International Civil Servants' Associations), which groups staff associations of the UN Agencies, and the annual CSAIO conferences (Conference of Staff Associations of International Organizations), where each Autumn representatives of international organizations based in Europe meet to discuss themes of common interest to better promote and defend the rights of the international civil servants. All these meetings allow us to remain informed on items that are directly or indirectly related to employment and social conditions of our colleagues in other international and Europ...

  4. Latency represents sound frequency in mouse IC

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Frequency is one of the fundamental parameters of sound.The frequency of an acoustic stimulus can be represented by a neural response such as spike rate,and/or first spike latency(FSL)of a given neuron.The spike rates/frequency function of most neurons changes with different acoustic ampli-tudes,whereas FSL/frequency function is highly stable.This implies that FSL might represent the fre-quency of a sound stimulus more efficiently than spike rate.This study involved representations of acoustic frequency by spike rate and FSL of central inferior colliculus(IC)neurons responding to free-field pure-tone stimuli.We found that the FSLs of neurons responding to characteristic frequency(CF)of sound stimulus were usually the shortest,regardless of sound intensity,and that spike rates of most neurons showed a variety of function according to sound frequency,especially at high intensities.These results strongly suggest that FSL of auditory IC neurons can represent sound frequency more precisely than spike rate.

  5. Latency represents sound frequency in mouse IC

    Institute of Scientific and Technical Information of China (English)

    QIU Qiang; TANG Jie; YU ZuLin; ZHANG Juan; ZHOU YingJie; XIAO ZhongJu; SHEN JunXian

    2007-01-01

    Frequency is one of the fundamental parameters of sound. The frequency of an acoustic stimulus can be represented by a neural response such as spike rate, and/or first spike latency (FSL) of a given neuron. The spike rates/frequency function of most neurons changes with different acoustic amplitudes, whereas FSL/frequency function is highly stable. This implies that FSL might represent the frequency of a sound stimulus more efficiently than spike rate. This study involved representations of acoustic frequency by spike rate and FSL of central inferior colliculus (IC) neurons responding to free-field pure-tone stimuli. We found that the FSLs of neurons responding to characteristic frequency (CF) of sound stimulus were usually the shortest, regardless of sound intensity, and that spike rates of most neurons showed a variety of function according to sound frequency, especially at high intensities.These results strongly suggest that FSL of auditory IC neurons can represent sound frequency more precisely than spike rate.

  6. Diversity and representativeness: two key factors

    CERN Multimedia

    Staff Association

    2013-01-01

    In the past few weeks many of you have filled out the questionnaire for preparing the upcoming Five-yearly review. Similarly, Staff Association members have elected their delegates to the Staff Council for the coming two years. Once again we would like to thank all those who have taken the time and effort to make their voice heard on these two occasions. Elections to the Staff Council Below we publish the new Staff Council with its forty delegates who will represent in 2014 and 2015 all CERN staff in the discussions with Management and Member States in the various bodies and committees. Therefore it is important that the Staff Council represents as far as possible the diversity of the CERN population. By construction, the election process with its electoral colleges and two-step voting procedure guarantees that all Departments, even the small ones, and the various staff categories are correctly represented. Figure 1 shows the participation rate in the elections. The average rate is just above 52 %, with ...

  7. HBD-2 is downregulated in oral carcinoma cells by DNA hypermethylation, and increased expression of hBD-2 by DNA demethylation and gene transfection inhibits cell proliferation and invasion.

    Science.gov (United States)

    Kamino, Yoshitaka; Kurashige, Yoshihito; Uehara, Osamu; Sato, Jun; Nishimura, Michiko; Yoshida, Koki; Arakawa, Toshiya; Nagayasu, Hiroki; Saitoh, Masato; Abiko, Yoshihiro

    2014-08-01

    Human β-defensin-2 (hBD-2) is a type of epithelial antimicrobial peptide. The expression level of hBD-2 mRNA is lower in oral carcinoma cells (OCCs) than in healthy oral epithelium. Yet, it is still unknown how hBD-2 expression is downregulated in OCCs. The present study investigated DNA hypermethylation of hBD-2 in OCCs and the effect of the demethylation and increased expression of hBD-2 on cell proliferation and invasion. Six different types of oral carcinoma cell lines (OSC-19, BSC-OF, SAS, HSC-2, HSC-4 and HSY) and normal oral keratinocytes (NOKs) were used. The expression levels of hBD-2 in all OCCs were significantly lower than that in the NOKs. Treatment with DNA methyltransferase inhibitor, 5-aza-dC, at the concentration of 50 µM significantly induced upregulation of expression of hBD-2 in the OCCs. Using methylation-specific PCR, DNA hypermethylation was observed in all OCCs. These results suggest that DNA hypermethylation is, at least in part, involved in the decreased expression of hBD-2 in OCCs. We examined the effect of 5-aza-dC on the cell proliferation and invasive ability of OCCs. The cell invasion assays showed that the number of OCCs treated with 5-aza-dC on the filters was significantly lower than that of the controls. We examined whether increased expression of hBD-2 generated by gene transfection inhibited the proliferation and invasion of SAS cells. The number of SAS cells exhibiting increased expression of hBD-2 on the filters in the invasion assay were significantly lower on day 7 when compared with the control. hBD-2 may function as a tumor suppressor. Increased expression of hBD-2 induced by demethylation or increased expression generated by gene transfection may be useful therapeutic methods for oral carcinoma.

  8. Representing clinical guidelines in UMl: a comparative study.

    Science.gov (United States)

    Hederman, Lucy; Smutek, Daniel; Wade, Vincent; Knape, Thomas

    2002-01-01

    Clinical guidelines can be represented using models, such as GLIF, specifically designed for healthcare guidelines. This paper demonstrates that they can also be modelled using a mainstream business modelling language such as UML. The paper presents a guideline in GLIF and as UML activity diagrams, and then presents a mapping of GLIF primitives to UML. The potential benefits of using a mainstream modelling language are outlined. These include availability of advanced modelling tools, transfer between modelling tools, and automation via business workflow technology.

  9. DNMT3L interacts with transcription factors to target DNMT3L/DNMT3B to specific DNA sequences: role of the DNMT3L/DNMT3B/p65-NFκB complex in the (de-)methylation of TRAF1.

    Science.gov (United States)

    Pacaud, Romain; Sery, Quentin; Oliver, Lisa; Vallette, François M; Tost, Jörg; Cartron, Pierre-François

    2014-09-01

    DNMT3L i.e. DNA (cytosine-5)-methyltransferase 3-like protein, is devoid of cytosine methyltransferase activity, despite clear homology to DNMT3A and DNMT3B, due to the mutation of key catalytic residues. However, DNMT3L participates in de novo methylation reactions through its direct interaction with DNMT3A and DNMT3B. In the present study, we investigated if DNMT3L interacts also directly with transcription factors (TFs). Using TF arrays, we identified 73 TFs that interacted with DNMT3L, 13 of which (ASH2L, ATF1, ATF3, BLZF1, CDX2, CERM, E2F3, E2F4, GCNF, GTF2I, GTF3C5, NFkB-p65 and RXRα) interacted only with DNMT3L, but not with DNMT3A/B. By focusing on the interaction with NFkB-p65, we demonstrate that DNMT3L forms a complex with DNMT3B and NFkB-p65 and that this complex is required for the control of DNA methylation at the TRAF1 promoter in the T98G glioma cell line. In addition, our experiments describe the DNA methylation at TRAF1 as being dynamic with a demethylation phase involving TET3. Thus, our data suggests that DNMT3L can address DNMT3A/B to specific sites by directly interacting with TFs that do not directly interact with DNMT3A/B. In summary, our data provide a new avenue for the direction of site-specific de novo DNA methylation catalyzed by DNMT3A/B.

  10. Total Synthesis and Antifungal Activity of Palmarumycin CP17 and Its Methoxy Analogues

    Directory of Open Access Journals (Sweden)

    Ruina Wang

    2016-05-01

    Full Text Available Total synthesis of naturally occurring spirobisnaphthalene palmarumycin CP17 and its methoxy analogues was first achieved through Friedel-Crafts acylation, Wolff-Kishner reduction, intramolecular cyclization, ketalization, benzylic oxidation, and demethylation using the inexpensive and readily available methoxybenzene, 1,2-dimethoxybenzene and 1,4-dimethoxybenzene and 1,8-dihydroxynaphthalene as raw materials. Demethylation with (CH33SiI at ambient temperature resulted in ring A aromatization and acetal cleavage to give rise to binaphthyl ethers. The antifungal activities of these spirobisnaphthalene derivatives were evaluated, and the results revealed that 5 and 9b exhibit EC50 values of 9.34 µg/mL and 12.35 µg/mL, respectively, against P. piricola.

  11. 40 CFR 72.26 - Delegation by designated representative and alternate designated representative.

    Science.gov (United States)

    2010-07-01

    ... designated representative may delegate, to one or more natural persons, his or her authority to make an... representative may delegate, to one or more natural persons, his or her authority to make an electronic... this part and parts 73 through 77 of this chapter. (c) In order to delegate authority to make an...

  12. CYP2C19基因型和CYP2C9对人肝微粒体中氟西汀N-去甲基代谢的影响%Effects of CYP2C19 genotype and CYP2C9 on fluoxetine N-demethylation in human liver microsomes

    Institute of Scientific and Technical Information of China (English)

    刘昭前; 舒焱; 黄松林; 王连生; 何楠; 周宏灏

    2001-01-01

    目的:本实验旨在研究CYP2C19基因型人肝微粒体中氟西汀N-去甲基代谢的酶促动力学特点并鉴定参与此代谢途径的细胞色素P-450酶.方法:测定基因型CYP2C19肝微粒体中去甲氟西汀形成的酶促动力学.鉴定氟西汀N-去甲基酶活性与细胞色素P-450 2C9,2C19,1A2和2D6酶活性的相关性,同时应用各种细胞色素P-450酶的选择性抑制剂和化学探针进行抑制实验,从而确定参与氟西汀N-去甲基代谢的细胞色素P-450酶.结果:去甲氟西汀生成的酶促动力学数据符合单酶模型,并具有Michaelis-Menten动力学特征.当底物浓度为氟西汀25μmol/L和100 μmol/L时,去甲氟西汀(N-FLU)的生成率分别与甲磺丁脲3-羟化酶活性显著相关(r1=0.821,P1=0.001;r2=0.668,P2=0.013),当底物浓度为氟西汀100 μmol/L时,N-FLU的生成率与S-美芬妥因4'-羟化酶活性显著相关(r=0.717,P=0.006).PM肝微粒中磺胺苯吡唑和醋竹桃霉素对氟西汀N-去甲基代谢的抑制作用显著大于EM(73%vs 45%,P<0.01).结论:在生理底物浓度下,CYP2C9是催化人肝微粒体中氟西汀N-去甲基代谢的主要CYP-450酶;而高底物浓度时,以CYP2C19的作用为主.%AIM: The present study was designed to define the kinetic behavior of fluoxetine N-demethylation in human liver microsomes and to identify the isoforms of cytochrome P-450 (CYP) involved in this metabolic pathway. METHODS: The kinetics of the formation of norfluoxetine was determined in human liver microsomes from six genotyped CYP2C19 extensive metabolizers (EM). The correlation studies between the fluoxetine N-demethylase activity and various CYP enzyme activities were performed. Selective inhibitors or chemical probes of various cytochrome P-450 isoforms were also employed. RESULTS: The kinetics of norfluoxetine formation in all liver microsomes were fitted by a singleenzyme Michaelis-Menten equation (mean Km=32 μmol/L±7

  13. Effects of 5-azacytidine on natural killer cell activating receptor expression in patients with refractory anemia with excess of blasts

    Directory of Open Access Journals (Sweden)

    Régis T. Costello

    2015-01-01

    Full Text Available Epigenetic drugs modify DNA methylation and are used in refractory anemia with excess of blasts (RAEB. These drugs may reactivate anti-oncogene expression and restore a normal phenotype instead of inducing antitumor toxicity, although they also have immunosuppressive effects on T-lymphocytes [1] In RAEB and acute myeloid leukemia, a defect in natural killer (NK cell cytotoxicity has been shown, which relies on abnormal expression of activating receptors. Previous study has shown that 5-azacytidine impaired mRNA synthesis and induced apoptosis in NK cells [2]. In this study we investigated the effect of the demethylating drug 5-azacytidine (Vidaza® on NK receptors with the hypothesis that demethylation of the promoters of activating NK receptor genes induces gene reactivation and thus may increase their expression.

  14. Recommendations for representative ballast water sampling

    Science.gov (United States)

    Gollasch, Stephan; David, Matej

    2017-05-01

    Until now, the purpose of ballast water sampling studies was predominantly limited to general scientific interest to determine the variety of species arriving in ballast water in a recipient port. Knowing the variety of species arriving in ballast water also contributes to the assessment of relative species introduction vector importance. Further, some sampling campaigns addressed awareness raising or the determination of organism numbers per water volume to evaluate the species introduction risk by analysing the propagule pressure of species. A new aspect of ballast water sampling, which this contribution addresses, is compliance monitoring and enforcement of ballast water management standards as set by, e.g., the IMO Ballast Water Management Convention. To achieve this, sampling methods which result in representative ballast water samples are essential. We recommend such methods based on practical tests conducted on two commercial vessels also considering results from our previous studies. The results show that different sampling approaches influence the results regarding viable organism concentrations in ballast water samples. It was observed that the sampling duration (i.e., length of the sampling process), timing (i.e., in which point in time of the discharge the sample is taken), the number of samples and the sampled water quantity are the main factors influencing the concentrations of viable organisms in a ballast water sample. Based on our findings we provide recommendations for representative ballast water sampling.

  15. [Sensitivity of four representative angular cephalometric measures].

    Science.gov (United States)

    Xü, T; Ahn, J; Baumrind, S

    2000-05-01

    Examined the sensitivity of four representative cephalometric angles to the detection of different vectors of craniofacial growth. Landmark coordinate data from a stratified random sample of 48 adolescent subjects were used to calculate conventional values for changes between the pretreatment and end-of-treatment lateral cephalograms. By modifying the end-of-treatment coordinate values appropriately, the angular changes could be recalculated reflecting three hypothetical situations: Case 1. What if there were no downward landmark displacement between timepoints? Case 2. What if there were no forward landmark displacement between timepoints? Case 3. What if there were no Nasion change? These questions were asked for four representative cephalometric angles: SNA, ANB, NAPg and UI-SN. For Case 1, the associations (r) between the baseline and the modified measure for the three angles were very highly significant (P < 0.001) with r2 values no lower than 0.94! For Case 2, however, the associations were much weaker and no r value reached significance. These angular measurements are less sensitive for measuring downward landmark displacement than they are for measuring forward landmark displacement.

  16. How Are Feedbacks Represented in Land Models?

    Directory of Open Access Journals (Sweden)

    Yang Chen

    2016-09-01

    Full Text Available Land systems are characterised by many feedbacks that can result in complex system behaviour. We defined feedbacks as the two-way influences between the land use system and a related system (e.g., climate, soils and markets, both of which are encompassed by the land system. Land models that include feedbacks thus probably more accurately mimic how land systems respond to, e.g., policy or climate change. However, representing feedbacks in land models is a challenge. We reviewed articles incorporating feedbacks into land models and analysed each with predefined indicators. We found that (1 most modelled feedbacks couple land use systems with transport, soil and market systems, while only a few include feedbacks between land use and social systems or climate systems; (2 equation-based land use models that follow a top-down approach prevail; and (3 feedbacks’ effects on system behaviour remain relatively unexplored. We recommend that land system modellers (1 consider feedbacks between land use systems and social systems; (2 adopt (bottom-up approaches suited to incorporating spatial heterogeneity and better representing land use decision-making; and (3 pay more attention to nonlinear system behaviour and its implications for land system management and policy.

  17. Quantifying Heuristic Bias: Anchoring, Availability, and Representativeness.

    Science.gov (United States)

    Richie, Megan; Josephson, S Andrew

    2017-07-28

    Construct: Authors examined whether a new vignette-based instrument could isolate and quantify heuristic bias. Heuristics are cognitive shortcuts that may introduce bias and contribute to error. There is no standardized instrument available to quantify heuristic bias in clinical decision making, limiting future study of educational interventions designed to improve calibration of medical decisions. This study presents validity data to support a vignette-based instrument quantifying bias due to the anchoring, availability, and representativeness heuristics. Participants completed questionnaires requiring assignment of probabilities to potential outcomes of medical and nonmedical scenarios. The instrument randomly presented scenarios in one of two versions: Version A, encouraging heuristic bias, and Version B, worded neutrally. The primary outcome was the difference in probability judgments for Version A versus Version B scenario options. Of 167 participants recruited, 139 enrolled. Participants assigned significantly higher mean probability values to Version A scenario options (M = 9.56, SD = 3.75) than Version B (M = 8.98, SD = 3.76), t(1801) = 3.27, p = .001. This result remained significant analyzing medical scenarios alone (Version A, M = 9.41, SD = 3.92; Version B, M = 8.86, SD = 4.09), t(1204) = 2.36, p = .02. Analyzing medical scenarios by heuristic revealed a significant difference between Version A and B for availability (Version A, M = 6.52, SD = 3.32; Version B, M = 5.52, SD = 3.05), t(404) = 3.04, p = .003, and representativeness (Version A, M = 11.45, SD = 3.12; Version B, M = 10.67, SD = 3.71), t(396) = 2.28, p = .02, but not anchoring. Stratifying by training level, students maintained a significant difference between Version A and B medical scenarios (Version A, M = 9.83, SD = 3.75; Version B, M = 9.00, SD = 3.98), t(465) = 2.29, p = .02, but not residents or attendings. Stratifying by heuristic and training level, availability maintained

  18. Representing the vacuum polarization on de Sitter

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, Katie E.; Woodard, Richard P. [Department of Physics, University of Florida, Gainesville, Florida 32611 (United States); Prokopec, Tomislav [Institute of Theoretical Physics (ITP) and Spinoza Institute, Utrecht University, Postbus 80195, 3508 TD Utrecht (Netherlands)

    2013-03-15

    Previous studies of the vacuum polarization on de Sitter have demonstrated that there is a simple, noncovariant representation of it in which the physics is transparent. There is also a cumbersome, covariant representation in which the physics is obscure. Despite being unwieldy, the latter form has a powerful appeal for those who are concerned about de Sitter invariance. We show that nothing is lost by employing the simple, noncovariant representation because there is a closed form procedure for converting its structure functions to those of the covariant representation. We also present a vastly improved technique for reading off the noncovariant structure functions from the primitive diagrams. And we discuss the issue of representing the vacuum polarization for a general metric background.

  19. Towards a representative periphytic diatom sample

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available The need to acquire a representative periphytic diatom sample for river water quality monitoring has been recognised in the development of existing diatom indices, important in the development and employment of diatom monitoring tools for the Water Framework Directive. In this study, a nested design with replication is employed to investigate the magnitude of variation in diatom biomass, composition and Trophic Diatom Index at varying scales within a small chalk river. The study shows that the use of artificial substrates may not result in diatom communities that are typical of the surrounding natural substrates. Periphytic diatom biomass and composition varies between artificial and natural substrates, riffles and glides and between two stretches of the river channel. The study also highlights the existence of high variation in diatom frustule frequency and biovolume at the individual replicate scale which may have implications for the use of diatoms in routine monitoring.

  20. STATISTICAL MODELS OF REPRESENTING INTELLECTUAL CAPITAL

    Directory of Open Access Journals (Sweden)

    Andreea Feraru

    2016-07-01

    Full Text Available This article entitled Statistical Models of Representing Intellectual Capital approaches and analyses the concept of intellectual capital, as well as the main models which can support enterprisers/managers in evaluating and quantifying the advantages of intellectual capital. Most authors examine intellectual capital from a static perspective and focus on the development of its various evaluation models. In this chapter we surveyed the classical static models: Sveiby, Edvisson, Balanced Scorecard, as well as the canonical model of intellectual capital. Among the group of static models for evaluating organisational intellectual capital the canonical model stands out. This model enables the structuring of organisational intellectual capital in: human capital, structural capital and relational capital. Although the model is widely spread, it is a static one and can thus create a series of errors in the process of evaluation, because all the three entities mentioned above are not independent from the viewpoint of their contents, as any logic of structuring complex entities requires.

  1. Antecedents and Consequences of Sales Representatives' Relationship Termination Competence

    DEFF Research Database (Denmark)

    Geersbro, Jens; Ritter, Thomas

    2013-01-01

    's customer portfolio, managers must not only provide a clear definition of the types of customers the organization does not want to serve, but must also implement termination routines within the organization. Managers also need to establish incentives for sales representatives to terminate relationships...... dissemination of the definition of a "non-customer", higher prevalence of termination routines, and increasing degrees of termination incentives. Acceptance of relationship termination at the firm level does not appear to have a significant impact on sales representatives' relationship termination competence....... In addition, termination competence significantly affects the value of customer portfolios. Practical implications: The findings suggest that managers should more actively consider relationship termination as a legitimate option in customer relationship management. In order to increase the value of a firm...

  2. Probability & Perception: The Representativeness Heuristic in Action

    Science.gov (United States)

    Lu, Yun; Vasko, Francis J.; Drummond, Trevor J.; Vasko, Lisa E.

    2014-01-01

    If the prospective students of probability lack a background in mathematical proofs, hands-on classroom activities may work well to help them to learn to analyze problems correctly. For example, students may physically roll a die twice to count and compare the frequency of the sequences. Tools such as graphing calculators or Microsoft Excel®…

  3. Probability & Perception: The Representativeness Heuristic in Action

    Science.gov (United States)

    Lu, Yun; Vasko, Francis J.; Drummond, Trevor J.; Vasko, Lisa E.

    2014-01-01

    If the prospective students of probability lack a background in mathematical proofs, hands-on classroom activities may work well to help them to learn to analyze problems correctly. For example, students may physically roll a die twice to count and compare the frequency of the sequences. Tools such as graphing calculators or Microsoft Excel®…

  4. Neuronal synchrony does not represent texture segregation

    NARCIS (Netherlands)

    Lamme, V.A.F.; Spekreijse, H.

    1998-01-01

    The visual environment is perceived as an organized whole of objects and their surroundings. In many visual cortical areas, however, neurons are typically activated when a stimulus is presented over a very limited portion of the visual field, the receptive field of that neuron(1-4). To bridge the ga

  5. 多发性骨髓瘤患者 DLC-1基因甲基化及三氧化二砷诱导 DLC-1基因去甲基化的研究%Hypermethylation of CpG island of DLC-1 gene and arsenic trioxide-induced DLC-1 gene demethylation in multiple myeloma

    Institute of Scientific and Technical Information of China (English)

    付海英; 沈建箴; 吴淡森

    2014-01-01

    detected by bisulfite sequencing PCR ( BSP ).And the mRNA expressions of DLC-1 and DNA methyltransferase ( DNMT1, T3a and 3b) were determined by real-time fluorescence quantitative PCR ( RTFQ-PCR).Results Hypermethylation of CpG island of DLC-1 gene was observed in 37/52 ( 71.15%) MM patients.DLC-1 gene was not expressed after methylation.As2 O3 could induce DLC-1 gene demethylation.After 72-houe treatments of 0.5, 1.0 and 2.0 μmol/L As2 O3 , the methylation rate of DLC-1 gene dropped from 95.38% to 63.07%, 30.00% and 7.69%.As compared with the untreated group , the expression of DLC-1 gene mRNA increased to ( 1.60 ±0.09 ) , ( 3.66 ±0.17 ) and (5.29 ±0.15) folds after exposures(all P<0.05).And As2O3 could induce the expression of DNMT1, DNMT3a,DNMT3b gene mRNA(all P<0.05).Conclusions Methylation of DLC-1 gene is essential in the pathogenesis of MM and may provide a new diagnostic technique and drug target for the treatment of MM .And As2 O3 may activate the expression of DLC-1 gene through demethylation.

  6. The Two Sides of the Representative Coin

    Directory of Open Access Journals (Sweden)

    Keith Sutherland

    2011-12-01

    Full Text Available In Federalist 10 James Madison drew a functional distinction between “parties” (advocates for factional interests and “judgment” (decision-making for the public good and warned of the corrupting effect of combining both functions in a “single body of men.” This paper argues that one way of overcoming “Madisonian corruption” would be by restricting political parties to an advocacy role, reserving the judgment function to an allotted (randomly-selected microcosm of the whole citizenry, who would determine the outcome of parliamentary debates by secret ballot—a division of labour suggested by James Fishkin’s experiments in deliberative polling. The paper then defends this radical constitutional proposal against Bernard Manin’s (1997 claim that an allotted microcosm could not possibly fulfil the “consent” requirement of Natural Right theory. Not only does the proposal challenge Manin’s thesis, but a 28th Amendment implementing it would finally reconcile the competing visions that have bedevilled representative democracy since the Constitutional Convention of 1787.

  7. The Two Sides of the Representative Coin

    Directory of Open Access Journals (Sweden)

    Keith Sutherland

    2011-12-01

    Full Text Available In Federalist 10 James Madison drew a functional distinction between “parties” (advocates for factional interests and “judgment” (decision-making for the public good and warned of the corrupting effect of combining both functions in a “single body of men.” This paper argues that one way of overcoming “Madisonian corruption” would be by restricting political parties to an advocacy role, reserving the judgment function to an allotted (randomly-selected microcosm of the whole citizenry, who would determine the outcome of parliamentary debates by secret ballot—a division of labour suggested by James Fishkin’s experiments in deliberative polling. The paper then defends this radical constitutional proposal against Bernard Manin’s (1997 claim that an allotted microcosm could not possibly fulfil the “consent” requirement of Natural Right theory. Not only does the proposal challenge Manin’s thesis, but a 28th Amendment implementing it would finally reconcile the competing visions that have bedevilled representative democracy since the Constitutional Convention of 1787.

  8. Do Female Representatives Adhere More Closely to Citizens’ Preferences Than Male Representatives?

    OpenAIRE

    2012-01-01

    We analyze whether female or male members of parliament adhere more closely to citizens’ revealed preferences with quasi-experimental data. By matching individual representatives’ voting behavior on legislative proposals with real referenda outcomes on the same issues, we identify the effect of gender on representatives’ responsiveness to revealed preferences of the majority of voters. Overall, female members of parliament tend to adhere less to citizens’ preferences than male parliam...

  9. Analysis of TET expression/activity and 5mC oxidation during normal and malignant germ cell development.

    Directory of Open Access Journals (Sweden)

    Daniel Nettersheim

    Full Text Available During mammalian development the fertilized zygote and primordial germ cells lose their DNA methylation within one cell cycle leading to the concept of active DNA demethylation. Recent studies identified the TET hydroxylases as key enzymes responsible for active DNA demethylation, catalyzing the oxidation of 5-methylcytosine to 5-hydroxymethylcytosine. Further oxidation and activation of the base excision repair mechanism leads to replacement of a modified cytosine by an unmodified one. In this study, we analyzed the expression/activity of TET1-3 and screened for the presence of 5 mC oxidation products in adult human testis and in germ cell cancers. By analyzing human testis sections, we show that levels of 5-hydroxymethylcytosine, 5-formylcytosine and 5-carboxylcytosine are decreasing as spermatogenesis proceeds, while 5-methylcytosine levels remain constant. These data indicate that during spermatogenesis active DNA demethylation becomes downregulated leading to a conservation of the methylation marks in mature sperm. We demonstrate that all carcinoma in situ and the majority of seminomas are hypomethylated and hypohydroxymethylated compared to non-seminomas. Interestingly, 5-formylcytosine and 5-carboxylcytosine were detectable in all germ cell cancer entities analyzed, but levels did not correlate to the 5-methylcytosine or 5-hydroxymethylcytosine status. A meta-analysis of gene expression data of germ cell cancer tissues and corresponding cell lines demonstrates high expression of TET1 and the DNA glycosylase TDG, suggesting that germ cell cancers utilize the oxidation pathway for active DNA demethylation. During xenograft experiments, where seminoma-like TCam-2 cells transit to an embryonal carcinoma-like state DNMT3B and DNMT3L where strongly upregulated, which correlated to increasing 5-methylcytosine levels. Additionally, 5-hydroxymethylcytosine levels were elevated, demonstrating that de novo methylation and active demethylation

  10. DNA methylation in porcine preimplantation embryos developed in-vivo or produced by in-vitro fertilization, parthenogenetic activation and somatic cell nuclear transfer

    DEFF Research Database (Denmark)

    Deshmukh, Rahul Shahaji; Østrup, Olga; Østrup, Esben;

    2011-01-01

    DNA demethylation and remethylation are crucial for reprogramming of the differentiated parental/somatic genome in the recipient ooplasm upon somatic cell nuclear transfer. Here, we analyzed the DNA methylation dynamics during porcine preimplantation development. Porcine in vivo developed (IV......), in vitro fertilized (IVF), somatic cell nuclear transfer (SCNT) and parthenogenetically activated (PA) embryos were evaluated for DNA methylation quantification at different developmental stages. Fertilized (IV and IVF) one-cell stages lacked a substantial active demethylation of the paternal genome....... Embryos produced under in vitro conditions had higher levels of DNA methylation than IV. A lineage-specific DNA methylation (hypermethylation of the inner cell mass and hypomethylation of the trophectoderm) was observed in porcine IV late blastocysts, but was absent in PA- and SCNT-derived blastocysts...

  11. DNA methylation in porcine preimplantation embryos developed in vivo and produced by in vitro fertilization, parthenogenetic activation and somatic cell nuclear transfer

    DEFF Research Database (Denmark)

    Deshmukh, Rahul Shahaji; Østrup, Olga; Østrup, Esben;

    2011-01-01

    DNA demethylation and remethylation are crucial for reprogramming of the differentiated parental/somatic genome in the recipient ooplasm upon somatic cell nuclear transfer. Here, we analyzed the DNA methylation dynamics during porcine preimplantation development. Porcine in vivo developed (IV......), in vitro fertilized (IVF), somatic cell nuclear transfer (SCNT) and parthenogenetically activated (PA) embryos were evaluated for DNA methylation quantification at different developmental stages. Fertilized (IV and IVF) one-cell stages lacked a substantial active demethylation of the paternal genome....... Embryos produced under in vitro conditions had higher levels of DNA methylation than IV. A lineage-specific DNA methylation (hypermethylation of the inner cell mass and hypomethylation of the trophectoderm) was observed in porcine IV late blastocysts, but was absent in PA- and SCNT-derived blastocysts...

  12. DNA methylation in porcine preimplantation embryos developed in vivo or produced by in vitro fertilization, parthenogenetic activation and somatic cell nuclear transfer

    DEFF Research Database (Denmark)

    Deshmukh, Rahul Shahaji; Østrup, Olga; Østrup, Esben;

    2011-01-01

    DNA demethylation and remethylation are crucial for reprogramming of the differentiated parental/somatic genome in the recipient ooplasm upon somatic cell nuclear transfer. Here, we analyzed the DNA methylation dynamics during porcine preimplantation development. Porcine in vivo developed (IV......), in vitro fertilized (IVF), somatic cell nuclear transfer (SCNT) and parthenogenetically activated (PA) embryos were evaluated for DNA methylation quantification at different developmental stages. Fertilized (IV and IVF) one-cell stages lacked a substantial active demethylation of the paternal genome....... Embryos produced under in vitro conditions had higher levels of DNA methylation than IV. A lineage-specific DNA methylation (hypermethylation of the inner cell mass and hypomethylation of the trophectoderm) was observed in porcine IV late blastocysts, but was absent in PA- and SCNT-derived blastocysts...

  13. Representative bureaucracy:does female police leadership affect gender-based violence arrests?

    OpenAIRE

    K. Johnston; Houston, John

    2016-01-01

    Representative bureaucracy theory postulates that passive representation leads to active representation of minority groups. This article investigates the passive representation of female police officers at leadership levels and the active representation of women vis-a-vis gender-based violence arrest rates in the UK. Much of the extant research on representative bureaucracy is located at street level, with evidence showing that discretionary power of minority bureaucrats can lead to active re...

  14. Representing Identity and Equivalence for Scientific Data

    Science.gov (United States)

    Wickett, K. M.; Sacchi, S.; Dubin, D.; Renear, A. H.

    2012-12-01

    Matters of equivalence and identity are central to the stewardship of scientific data. In order to properly prepare for and manage the curation, preservation and sharing of digitally-encoded data, data stewards must be able to characterize and assess the relationships holding between data-carrying digital resources. However, identity-related questions about resources and their information content may not be straightforward to answer: for example, what exactly does it mean to say that two files contain the same data, but in different formats? Information content is frequently distinguished from particular representations, but there is no adequately developed shared understanding of what this really means and how the relationship between content and its representations hold. The Data Concepts group at the Center for Informatics Research in Science and Scholarship (CIRSS), University of Illinois at Urbana Champaign, is developing a logic-based framework of fundamental concepts related to scientific data to support curation and integration. One project goal is to develop precise accounts of information resources carrying the same data. We present two complementary conceptual models for information representation: the Basic Representation Model (BRM) and the Systematic Assertion Model (SAM). We show how these models provide an analytical account of digitally-encoded scientific data and a precise understanding of identity and equivalence. The Basic Representation Model identifies the core entities and relationships involved in representing information carried by digital objects. In BRM, digital objects are symbol structures that express propositional content, and stand in layered encoding relationships. For example, an RDF description may be serialized as either XML or N3, and those expressions in turn may be encoded as either UTF-8 or UTF-16 sequences. Defining this encoding stack reveals distinctions necessary for a precise account of identity and equivalence

  15. HOW TO REPRESENT THE GENETIC CODE?

    Directory of Open Access Journals (Sweden)

    N.S. Santos-Magalhães

    2004-05-01

    Full Text Available The advent of molecular genetic comprises a true revolution of far-reaching consequences for human-kind, which evolved into a specialized branch of the modern-day Biochemistry. The analysis of specicgenomic information are gaining wide-ranging interest because of their signicance to the early diag-nosis of disease, and the discovery of modern drugs. In order to take advantage of a wide assortmentof signal processing (SP algorithms, the primary step of modern genomic SP involves convertingsymbolic-DNA sequences into complex-valued signals. How to represent the genetic code? Despitebeing extensively known, the DNA mapping into proteins is one of the relevant discoveries of genetics.The genetic code (GC is revisited in this work, addressing other descriptions for it, which can beworthy for genomic SP. Three original representations are discussed. The inner-to-outer map buildson the unbalanced role of nucleotides of a codon. A two-dimensional-Gray genetic representationis oered as a structured map that can help interpreting DNA spectrograms or scalograms. Theseare among the powerful visual tools for genome analysis, which depends on the choice of the geneticmapping. Finally, the world-chart for the GC is investigated. Evoking the cyclic structure of thegenetic mapping, it can be folded joining the left-right borders, and the top-bottom frontiers. As aresult, the GC can be drawn on the surface of a sphere resembling a world-map. Eight parallels oflatitude are required (four in each hemisphere as well as four meridians of longitude associated tofour corresponding anti-meridians. The tropic circles have 11.25o, 33.75o, 56.25o, and 78.5o (Northand South. Starting from an arbitrary Greenwich meridian, the meridians of longitude can be plottedat 22.5o, 67.5o, 112.5o, and 157.5o (East and West. Each triplet is assigned to a single point on thesurface that we named Nirenberg-Kohamas Earth. Despite being valuable, usual representations forthe GC can be

  16. Enzymatic C-demethylation of 1-[2-(5-tert-butyl-[1,3,4] oxadiazole-2-carbonyl)-4-fluoro-pyrrolidin-1-yl]-2-(2-hydroxy-1,1-dimethyl-ethylamino)-ethanone (LC15-0133) in rat liver microsomes.

    Science.gov (United States)

    Yoo, Hye Hyun; Chung, Hye Jin; Lee, Jaeick; Lee, Chang-Seok; Kang, Min Jung; Kim, Dong-Hyun

    2008-03-01

    The in vitro metabolism of 1-[2-(5-tert-butyl-[1,3,4] oxadiazole-2-carbonyl)-4-fluoro-pyrrolidin-1-yl]-2-(2-hydroxy-1,1-dimethyl-ethylamino)-ethanone (LC15-0133), a novel dipeptidyl peptidase-4 inhibitor, was investigated using a hepatic microsomal system. The structures of the metabolites were characterized using mass spectral analysis and by comparison with synthetic references. The in vitro incubation of LC15-0133 with rat liver microsomes resulted in the formation of six metabolites, with the major metabolic reactions being hydroxylation and carbonyl reduction. Of the metabolites, a C-demethylated metabolite (M4) was identified, but was only detected in rat liver microsomes; experimental evidence revealed that the C-demethylated metabolite was generated by nonenzymatic decarboxylation of the carboxyl metabolite (M1). Nonenzymatic decarboxylation is postulated to occur due to the resonance stabilization by the oxadiazole ring attached to the tert-butyl moiety.

  17. Demethylation of the pesticide methoxychlor in liver and intestine from untreated, methoxychlor-treated, and 3-methylcholanthrene-treated channel catfish (Ictalurus punctatus): evidence for roles of CYP1 and CYP3A family isozymes.

    Science.gov (United States)

    Stuchal, Leah D; Kleinow, Kevin M; Stegeman, John J; James, Margaret O

    2006-06-01

    Exposure to the organochlorine pesticide methoxychlor (MXC) is associated with endocrine disruption in several species through biotransformation to mono-desmethyl-MXC (OH-MXC) and bis-desmethyl-MXC (HPTE), which interact with estrogen receptors. The biotransformation of [14C]methoxychlor was examined in channel catfish (Ictalurus punctatus), a freshwater species found in the southern United States. Hepatic microsomes formed OH-MXC and HPTE, assessed by comigration with authentic standards. The Km for OH-MXC formation by control liver microsomes was 3.8 +/- 1.3 microM (mean +/- S.D., n = 4), and Vmax was 131 +/- 53 pmol/min/mg protein. These values were similar to those of catfish pretreated with 2 mg/kg methoxychlor i.p. for 6 days (Km 3.3 +/- 0.8 microM and Vmax 99 +/- 17 pmol/min/mg) but less (p Methoxychlor pretreatment significantly reduced intestinal metabolite formation from 32 +/- 4 to 15 +/- 6 pmol/min/mg (mean +/- S.D., n = 4), whereas 3-MC treatment significantly increased OH-MXC production to 72 +/- 22 pmol/min/mg. Ketoconazole, clotrimazole, and alpha-naphthoflavone all decreased the production of OH-MXC in liver microsomes, whereas alpha-naphthoflavone stimulated HPTE formation, suggesting that CYP1 and CYP3 family isozymes demethylated methoxychlor. The results suggest that the formation of estrogenic metabolites from methoxychlor would be more rapid in catfish coexposed to CYP1 inducers.

  18. Representing Kidney Development Using the Gene Ontology

    Science.gov (United States)

    Alam-Faruque, Yasmin; Hill, David P.; Dimmer, Emily C.; Harris, Midori A.; Foulger, Rebecca E.; Tweedie, Susan; Attrill, Helen; Howe, Douglas G.; Thomas, Stephen Randall; Davidson, Duncan; Woolf, Adrian S.; Blake, Judith A.; Mungall, Christopher J.; O’Donovan, Claire; Apweiler, Rolf; Huntley, Rachael P.

    2014-01-01

    Gene Ontology (GO) provides dynamic controlled vocabularies to aid in the description of the functional biological attributes and subcellular locations of gene products from all taxonomic groups (www.geneontology.org). Here we describe collaboration between the renal biomedical research community and the GO Consortium to improve the quality and quantity of GO terms describing renal development. In the associated annotation activity, the new and revised terms were associated with gene products involved in renal development and function. This project resulted in a total of 522 GO terms being added to the ontology and the creation of approximately 9,600 kidney-related GO term associations to 940 UniProt Knowledgebase (UniProtKB) entries, covering 66 taxonomic groups. We demonstrate the impact of these improvements on the interpretation of GO term analyses performed on genes differentially expressed in kidney glomeruli affected by diabetic nephropathy. In summary, we have produced a resource that can be utilized in the interpretation of data from small- and large-scale experiments investigating molecular mechanisms of kidney function and development and thereby help towards alleviating renal disease. PMID:24941002

  19. Understanding and representing natural language meaning

    Science.gov (United States)

    Waltz, D. L.; Maran, L. R.; Dorfman, M. H.; Dinitz, R.; Farwell, D.

    1982-12-01

    During this contract period the authors have: (1) continued investigation of events and actions by means of representation schemes called 'event shape diagrams'; (2) written a parsing program which selects appropriate word and sentence meanings by a parallel process know as activation and inhibition; (3) begun investigation of the point of a story or event by modeling the motivations and emotional behaviors of story characters; (4) started work on combining and translating two machine-readable dictionaries into a lexicon and knowledge base which will form an integral part of our natural language understanding programs; (5) made substantial progress toward a general model for the representation of cognitive relations by comparing English scene and event descriptions with similar descriptions in other languages; (6) constructed a general model for the representation of tense and aspect of verbs; (7) made progress toward the design of an integrated robotics system which accepts English requests, and uses visual and tactile inputs in making decisions and learning new tasks.

  20. Registration Appointment and Services for Representatives Management Information

    Data.gov (United States)

    Social Security Administration — A new internet/intranet application that collects all representative information and establishes the relationship between the claimant and the representative. Allow...

  1. Japanese practicing physicians' relationships with pharmaceutical representatives: a national survey.

    Directory of Open Access Journals (Sweden)

    Sayaka Saito

    Full Text Available BACKGROUND: Previous surveys on the relationship between physicians and pharmaceutical representatives (PRs have been of limited quality. The purpose of our survey of practicing physicians in Japan was to assess the extent of their involvement in pharmaceutical promotional activities, physician characteristics that predict such involvement, attitudes toward relationships with PRs, correlations between the extent of involvement and attitudes, and differences in the extent of involvement according to self-reported prescribing behaviors. METHODS AND FINDINGS: From January to March 2008, we conducted a national survey of 2621 practicing physicians in seven specialties: internal medicine, general surgery, orthopedic surgery, pediatrics, obstetrics-gynecology, psychiatry, and ophthalmology. The response rate was 54%. Most physicians met with PRs (98%, received drug samples (85% and stationery (96%, and participated in industry-sponsored continuing medical education (CME events at the workplace (80% and outside the workplace (93%. Half accepted meals outside the workplace (49% and financial subsidies to attend CME events (49%. Rules at the workplace banning both meetings with PRs and gifts predicted less involvement of physicians in promotional activities. Physicians valued information from PRs. They believed that they were unlikely to be influenced by promotional activities, but that their colleagues were more susceptible to such influence than themselves. They were divided about the appropriateness of low-value gifts. The extent of physician involvement in promotional activities was positively correlated with the attitudes that PRs are a valuable source of information and that gifts are appropriate. The extent of such involvement was higher among physicians who prefer to ask PRs for information when a new medication becomes available, physicians who are not satisfied with patient encounters ending only with advice, and physicians who prefer to

  2. Japanese Practicing Physicians' Relationships with Pharmaceutical Representatives: A National Survey

    Science.gov (United States)

    Saito, Sayaka; Mukohara, Kei; Bito, Seiji

    2010-01-01

    Background Previous surveys on the relationship between physicians and pharmaceutical representatives (PRs) have been of limited quality. The purpose of our survey of practicing physicians in Japan was to assess the extent of their involvement in pharmaceutical promotional activities, physician characteristics that predict such involvement, attitudes toward relationships with PRs, correlations between the extent of involvement and attitudes, and differences in the extent of involvement according to self-reported prescribing behaviors. Methods and Findings From January to March 2008, we conducted a national survey of 2621 practicing physicians in seven specialties: internal medicine, general surgery, orthopedic surgery, pediatrics, obstetrics-gynecology, psychiatry, and ophthalmology. The response rate was 54%. Most physicians met with PRs (98%), received drug samples (85%) and stationery (96%), and participated in industry-sponsored continuing medical education (CME) events at the workplace (80%) and outside the workplace (93%). Half accepted meals outside the workplace (49%) and financial subsidies to attend CME events (49%). Rules at the workplace banning both meetings with PRs and gifts predicted less involvement of physicians in promotional activities. Physicians valued information from PRs. They believed that they were unlikely to be influenced by promotional activities, but that their colleagues were more susceptible to such influence than themselves. They were divided about the appropriateness of low-value gifts. The extent of physician involvement in promotional activities was positively correlated with the attitudes that PRs are a valuable source of information and that gifts are appropriate. The extent of such involvement was higher among physicians who prefer to ask PRs for information when a new medication becomes available, physicians who are not satisfied with patient encounters ending only with advice, and physicians who prefer to prescribe brand

  3. Posttranslational modifications of the histone 3 tail and their impact on the activity of histone lysine demethylases in vitro.

    Directory of Open Access Journals (Sweden)

    Brian Lohse

    Full Text Available Posttranslational modifications (PTMs of the histone H3 tail such as methylation, acetylation and phosphorylation play important roles in epigenetic signaling. Here we study the effect of some of these PTMs on the demethylation rates of methylated lysine 9 in vitro using peptide substrates mimicking histone H3. Various combinations with other PTMs were employed to study possible cross-talk effects by comparing enzyme kinetic characteristics. We compared the kinetics of histone tail substrates for truncated histone lysine demethylases KDM4A and KDM4C containing only the catalytic core (cc and some combinations were characterized on full length (FL KDM4A and KDM4C. We found that the substrates combining trimethylated K4 and K9 resulted in a significant increase in the catalytic activity for FL-KDM4A. For the truncated versions of KDM4A and KDM4C a two-fold increase in the catalytic activity toward bis-trimethylated substrates could be observed. Furthermore, a significant difference in the catalytic activity between dimethylated and trimethylated substrates was found for full length demethylases in line with what has been reported previously for truncated demethylases. Histone peptide substrates phosphorylated at T11 could not be demethylated by neither truncated nor full length KDM4A and KDM4C, suggesting that phosphorylation of threonine 11 prevents demethylation of the H3K9me3 mark on the same peptide. Acetylation of K14 was also found to influence demethylation rates significantly. Thus, for truncated KDM4A, acetylation on K14 of the substrate leads to an increase in enzymatic catalytic efficiency (k cat/K m, while for truncated KDM4C it induces a decrease, primarily caused by changes in K m. This study demonstrates that demethylation activities towards trimethylated H3K9 are significantly influenced by other PTMs on the same peptide, and emphasizes the importance of studying these interactions at the peptide level to get a more detailed

  4. Actividad física deportiva en una muestra representativa de la población de la Región de Murcia Physical sports activity in a representative sample of the population of Región de Murcia, Spain

    Directory of Open Access Journals (Sweden)

    M.T. Martínez-Ros

    2003-02-01

    the region of Murcia, Spain, and to analyze its association with major demographic and socioeconomic determinants and other cardiovascular risk factors. Methods: Survey of a representative sample of the population aged between 18 and 65 years from Murcia was performed using multistage random sampling with definition of the sample quotas. A total of 3091 individuals were surveyed. The frequency and duration of intense physical sports activity during the two weeks prior to the survey was obtained using a validated questionnaire. Information was also collected on socioeconomic variables, smoking, blood pressure, weight and height and a blood test was performed to determine plasma lipids. Intense or vigorous physical activity (≥ 6 Metabolic Equivalents [MET] was measured in kcal/day and reduced to hours/week to give three categories: no vigorous physical activity, less than 2 hours/week, and 2 hours/week or more. Results: Overall, 17.8% (95% CI: 16.6-19.0 of the adult population of the region of Murcia performed intense physical activity for ≥ 2 hours/week. The figures were twice as high in men (23.1%; 95% CI: 21.0-25.2 than in women (12.5%; 95% CI: 10.9-14.1. In the logistic regression analysis, a higher frequency of intense physical activity was associated with age, level of education and employment situation. In men it was also associated with occupation and residence in urban areas. Conclusions: During the study period, one in five adults in the region of Murcia took intense physical sports activity with a frequency and duration that were compatible with the prevention of episodes of coronary ischemia.

  5. Solar Heliospheric and INterplanetary Environment (SHINE) Students - Student Representatives' Perspectives

    Science.gov (United States)

    Pahud, D. M.; Niembro, T.

    2014-12-01

    The SHINE workshop is an annual meeting of solar and heliospheric scientists which, in addition to aiming to improve understanding of solar disturbances and their propagation to, and effect, on the Earth (shinecon.org), is dedicated to actively supporting students. This dedication is substantiated in part through the National Science Foundation (NSF) providing funding for student attendance to the workshop, which enables student participation. Another example of SHINE's commitment to its student members is the incorporation of a Student Day prior to the workshop since 2003, entirely organized and run by two student representatives. While there are variations in format from year to year, Student Day consists of tutorials and research talks exclusively by student volunteers to an audience of only students. The day is intended to provide a low-stress environment for students to learn about the various topics addressed during the workshop, to ask questions freely, and to engage in scientific discussion with other students which hopefully is a catalyst for collaboration. As a result of positive experiences, over the past decade student attendance and participation in the workshop have increased. At the SHINE 2014 workshop, nearly a third of attendees were students. SHINE student visibility has increased over the years, with student posters being advertised at breakfast, inclusion of a student day summary by the student representatives during a plenary session, and continued support from the steering committee. Students are also promoting a broader impact of SHINE sciences via increased social media presence. From a student representative's perspective, SHINE has built and fostered a healthy student community and encourages students to engage in shaping the future of the field.

  6. 29 CFR 417.19 - Assistant Secretary's representative.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 2 2010-07-01 2010-07-01 false Assistant Secretary's representative. 417.19 Section 417.19... Union To Take Appropriate Remedial Action Following Subpart A Procedures § 417.19 Assistant Secretary's representative. The Assistant Secretary shall appoint a representative or representatives whose functions shall...

  7. 48 CFR 1830.7002-3 - Representative investment calculations.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Representative investment... Representative investment calculations. (a) The calculation of the representative investment requires... accounting period, the contractor shall either: (1) Determine a representative investment for the...

  8. Heavy-ion radiation induces both activation of multiple endogenous transposable elements and alterations in DNA methylation in rice

    Science.gov (United States)

    Zhang, Meng; Sun, Yeqing; Li, Xishan; Xiaolin, Cui; Li, Xiang

    2012-07-01

    Space radiation represents a complex environmental condition in which several interacting factors such as electron, neutron, proton, heavy-ion are involved, which may provoke stress responses and jeopardize genome integrity. Given the inherent property of epigenetic modifications to respond to intrinsic aswell as external perturbations, it is conceivable that epigenetic markers like DNA methylation and transposition may undergo alterations in response to space radiation. Cytosine DNA methylation plays important roles in maintaining genome stability and controlling gene expression. A predominant means for Transposable elements (TEs) to cause genetic instability is via their transpositional activation. To find the detailed molecular characterization of the nature of genomic changes induced by space radiation, the seeds of rice were exposed to 0.02, 0.2, 1, 2 and 20 Gy dose of ^{12}C heavy-ion radiation, respectively. We found that extensive alteration in both DNA methylation and gene expression occurred in rice plants after different dose of heavy-ion radiation. Here we shown that heavy-ion radiation has induced transposition of mPing and Tos17 in rice, which belong to distinct classes including the miniature inverted terminal repeat TEs (MITEs) and long-terminal repeat (LTR) retrotransposons, respectively. mPing and Tos17 mobility were found to correlate with cytosine methylation alteration detected by MSAP and genetic variation detected by AFLP. The result showed that at least in some cases transposition of TEs was associated with cytosine demethylation within the elements. Our results implicate that the heavy-ion radiation represents a potent mutagenic agent that can cause genomic instabilities by eliciting transposition of endogenous TEs in rice. Keywords: Heavy-ion radiation, DNA methylation, Transposable elements, mPing, Tos17

  9. Brain mechanisms for representing what another person sees.

    Science.gov (United States)

    Heyda, Ratha D; Green, Steven R; Vander Wyk, Brent C; Morris, James P; Pelphrey, Kevin A

    2010-04-01

    We used functional magnetic resonance imaging (fMRI) and a naturalistic joint attention scenario to evaluate two, alternative hypotheses concerning the social brain. The first, Content Specific Attribution hypothesis, was that core regions previously identified as being involved in social cognition also participate in representing the contents of another mind. The second, Dual Role hypothesis, was that extrastriate, category-specific visual regions respond to a visible stimulus of a specific category and to the same stimulus occluded, but when it appears to be the focus of another person's visual attention. Participants viewed category-specific stimuli (Place and Body images) to localize the extrastriate body area (EBA) and parahippocampal place area (PPA). Then, they observed a computerized character viewing each stimulus category, occluded from the participant's view. In support of the Content Specific Attribution hypothesis, whole-brain analyses revealed that viewing someone else looking at an occluded picture of a body activated brain regions previously associated with components of social cognition more than viewing someone else looking at an occluded picture of a place. Counter to the Dual Role hypothesis, functional region of interest (ROI) analyses revealed that the EBA and PPA were not clearly involved in representing what the character was seeing.

  10. [Dangerous liaisons--physicians and pharmaceutical sales representatives].

    Science.gov (United States)

    Granja, Mónica

    2005-01-01

    Interactions between physicians and detailers (even when legitimate ones) raise scientific and ethical questions. In Portugal little thinking and discussion has been done on the subject and the blames for bribery have monopolized the media. This work intended to review what has been said in medical literature about these interactions. How do physicians see themselves when interacting with pharmaceutical companies and their representatives? Do these companies in fact change their prescriptive behaviour, and, if so, how do they change it? How can physicians interact with detailers and still keep their best practice? A Medline research, from 1966 till 2002, was performed using the key-words as follows. A database similar to Medline but concerning medical journals published in Portugal, Index das Revistas Médicas Portuguesas, was also researched from 1992 to 2002. Pharmaceutical companies are profit bound and they allot promoting activities, and detailing in particular, huge amounts of money. Most physicians hold firmly to the belief that they are able to resist and not be influenced by drug companies promotion activities. Nevertheless, all previous works on literature tell us the opposite. Market research also indicates that detailers effectively promote drug sales. Various works also suggest that the information detailers provide to physicians may be largely incorrect, even comparing it to the written information provided by the pharmaceutical companies they work for. The frequency at which portuguese physicians (especially family physicians) contact with pharmaceutical sales representatives is higher than the frequency reported in countries where the available studies come from (namely, Canada and the United States of America). This may put portuguese physicians at a higher risk, making it imperative that work and wide debate are initiated among the class.

  11. Reactivating aberrantly hypermethylated p15 gene in leukemic T cells by a phenylhexyl isothiocyanate mediated inter-active mechanism on DNA and chromatin

    Directory of Open Access Journals (Sweden)

    Jiang Shaohong

    2010-11-01

    Full Text Available Abstract Background We have previously demonstrated that phenylhexyl isothiocyanate (PHI, a synthetic isothiocyanate, inhibits histone deacetylases and remodels chromatins to induce growth arrest in HL-60 myeloid leukemia cells in a concentration-dependent manner. Methods To investigate the effect of PHI, a novel histone deacetylases inhibitor (HDACi, on demethylation and activation of transcription of p15 in acute lymphoid leukemia cell line Molt-4, and to further decipher the potential mechanism of demethylation, DNA sequencing and modified methylation specific PCR (MSP were used to screen p15-M and p15-U mRNA after Molt-4 cells were treated with PHI, 5-Aza and TSA. DNA methyltransferase 1 (DNMT1, 3A (DNMT3A, 3B (DNMT3B and p15 mRNA were measured by RT-PCR. P15 protein, acetylated histone H3 and histone H4 were detected by Western Blot. Results The gene p15 in Molt-4 cells was hypermethylated and inactive. Hypermethylation of gene p15 was attenuated and p15 gene was activated de novo after 5 days exposure to PHI in a concentration-dependent manner. DNMT1 and DNMT3B were inhibited by PHI (P Conclusion PHI could induce both DNA demethylation and acetylated H3 and H4 accumulation in Molt-4 cells. Hypermethylation of gene p15 was reversed and p15 transcription could be reactivated de novo by PHI.

  12. Marketing norm perception among medical representatives in Indian pharmaceutical industry.

    Science.gov (United States)

    Nagashekhara, Molugulu; Agil, Syed Omar Syed; Ramasamy, Ravindran

    2012-03-01

    Study of marketing norm perception among medical representatives is an under-portrayed component that deserves further perusal in the pharmaceutical industry. The purpose of this study is to find out the perception of marketing norms among medical representatives. The research design is quantitative and cross sectional study with medical representatives as unit of analysis. Data is collected from medical representatives (n=300) using a simple random and cluster sampling using a structured questionnaire. Results indicate that there is no difference in the perception of marketing norms among male and female medical representatives. But there is a difference in opinion among domestic and multinational company's medical representatives. Educational back ground of medical representatives also shows the difference in opinion among medical representatives. Degree holders and multinational company medical representatives have high perception of marketing norms compare to their counterparts. The researchers strongly believe that mandatory training on marketing norms is beneficial in decision making process during the dilemmas in the sales field.

  13. 去甲苔藓葸噻吩抑制血管生成作用的体外实验研究%Anti-angiogenesis effect of Demethyl bryoanthrathiophene (DBT) in vitro

    Institute of Scientific and Technical Information of China (English)

    Chen Zhong; Xiangdong Zhou; Minghui Zhang; Yide Hu

    2011-01-01

    Objective:The aim of the study was to investigate the effect of Demethyl bryoanthrathiophene (DBT) on pro-liferations of human umbilical vein endothelial cells (HUVECs) and human lung adenocarcinoma cell line A549, and antian-giogenic effect of DBT on HUVECs in vitro. Methods: MTT assay was used to observe the effect of DBT on proliferations of HUVECs and A549 cells, fiat plate scarification assay and tube formation in vitro test were used to observe the impact of DBT on migration and vaso-formed ability of HUVECs. The effects of DBT on apoptosis and cell cycle of HUVECs were calculated by flow cytometry. Results: MTT assay showed that treatment with DBT resulted in strong inhibition to the growth of HUVECs and A549 cells. The inhibition effects of DBT on HUVECs and A549 cells were related to dosage and times of dependency.In different doses of DBT (0.16, 0.32 and 0.48 μmol/L) of fiat plate scarification for 24 h, inhibition rates of DBT to migration of HUVECs were 14.70%, 38.23% and 58.82%, respectively. In dose of DBT from 0.04, 0.20 to 0.40 μmol/L for 24 h in tube formation, there were significance differences (P < 0.01) in the decreasing number of angiogenesis and incomplete blood vessel compared with control groups. All results showed that DBT promoted the apoptosis rate of HUVECs, and the increase of concentration of DBT accompanied the acceleration of apoptosis rate. Conclusion: DBT could inhibit the proliferations of HUVECs and A549 cells, and effectively suppress angiogenesis in vitro.

  14. In vitro glucuronidation of the primary metabolite of 10-chloromethyl-11-demethyl-12-oxo-calanolide A by human liver microsomes and its interactions with UDP-glucuronosyltransferase substrates.

    Science.gov (United States)

    Liu, Xin; Sheng, Li; Zhao, Manman; Mi, Jiaqi; Liu, Zhihao; Li, Yan

    2015-02-01

    F18 (10-chloromethyl-11-demethyl-12-oxo-calanolide), an analog of (+)-Calanolide A, is a novel small-molecule nonnucleoside reverse transcriptase inhibitor for the therapy of human immunodeficiency virus (HIV) infection. M3, the most abundant primary metabolite of F18 in human liver microsomes (HLMs) and rat liver microsomes (RLMs), is mainly excreted in bile as a glucuronide conjugate in rats after oral administration. The aim of this study was to identify the UDP glucuronosyltransferase (UGT) isoforms involved in the glucuronidation of M3 by HLMs and recombinant human UGTs and investigate the metabolic interactions of M3 with the substrates of UGTs in HLMs. As a result, UGT1A1 was the major isozyme responsible for the glucuronidation of M3, followed by UGT1A4, UGT1A9 and UGT2B7. M3 exhibited significant inhibition against UGT1A9 and UGT2B7 in both HLMs and recombinant human UGTs. In addition, M3 inhibited UGT1A9 catalyzed mycophenolic acid (MPA) glucuronidation with Ki of 0.39 μM, and M3 also inhibited the glucuronidation of 3'-azido-3'-deoxythymidine (AZT) by a "mixed-type" mechanism with Ki of 16.8 μM. The results suggest that UGT1A1 provides the major contribution to M3 glucuronidation in vitro and M3 has the potential to interact with xenobiotics and endogenous chemicals that are UGT1A9 and UGT 2B7 substrates.

  15. Drosophila p53 is required to increase the levels of the dKDM4B demethylase after UV-induced DNA damage to demethylate histone H3 lysine 9.

    Science.gov (United States)

    Palomera-Sanchez, Zoraya; Bucio-Mendez, Alyeri; Valadez-Graham, Viviana; Reynaud, Enrique; Zurita, Mario

    2010-10-01

    Chromatin undergoes a variety of changes in response to UV-induced DNA damage, including histone acetylation. In human and Drosophila cells, this response is affected by mutations in the tumor suppressor p53. In this work, we report that there is a global decrease in trimethylated Lys-9 in histone H3 (H3K9me3) in salivary gland cells in wild type flies in response to UV irradiation. In contrast, flies with mutations in the Dmp53 gene have reduced basal levels of H3K9me3, which are then increased after UV irradiation. The reduction of H3K9me3 in response to DNA damage occurs preferentially in heterochromatin. Our experiments demonstrate that UV irradiation enhances the levels of Lys-9 demethylase (dKDM4B) transcript and protein in wild type flies, but not in Dmp53 mutant flies. Dmp53 binds to a DNA element in the dKdm4B gene as a response to UV irradiation. Furthermore, heterozygous mutants for the dKdm4B gene are more sensitive to UV irradiation; they are deficient in the removal of cyclobutane-pyrimidine dimers, and the decrease of H3K9me3 levels following DNA damage is not observed in dKdm4B mutant flies. We propose that in response to UV irradiation, Dmp53 enhances the expression of the dKDM4B histone demethylase, which demethylates H3K9me3 preferentially in heterochromatin regions. This mechanism appears to be essential for the proper function of the nucleotide excision repair system.

  16. Se14, encoding a JmjC domain-containing protein, plays key roles in long-day suppression of rice flowering through the demethylation of H3K4me3 of RFT1.

    Directory of Open Access Journals (Sweden)

    Takayuki Yokoo

    Full Text Available Floral transition from the vegetative to the reproductive growth phase is a major change in the plant life cycle and a key factor in reproductive success. In rice (Oryza sativa L., a facultative short-day plant, numerous flowering time and flower formation genes that control floral transition have been identified and their physiological effects and biochemical functions have been clarified. In the present study, we used a Se14-deficient mutant line (HS112 and other flowering mutant lines to investigate the photoperiodic response, chromosomal location and function in the photoperiod sensitivity of the Se14 gene. We also studied the interactive effects of this locus with other crucial flowering time genes. We found that Se14 is independent of the known photoperiod-sensitive genes, such as Hd1 and Ghd7, and is identical to Os03g0151300, which encodes a Jumonji C (JmjC domain-containing protein. Expression analysis revealed that the expressions of RFT1, a floral initiator known as a "florigen-like gene", and Ehd1 were up-regulated in HS112, whereas this up-regulation was not observed in the original variety of 'Gimbozu'. ChIP assays of the methylation states of histone H3 at lysine 4 (H3K4 revealed that the trimethylated H3K4 in the promoter region of the RFT1 chromatin was significantly increased in HS112. We conclude that Se14 is a novel photoperiod-sensitivity gene that has a suppressive effect on floral transition (flowering time under long day-length conditions through the modification of chromatin structure by H3K4me3 demethylation in the promoter region of RFT1.

  17. All-trans retinoic acid promotes TGF-β-induced Tregs via histone modification but not DNA demethylation on Foxp3 gene locus.

    Directory of Open Access Journals (Sweden)

    Ling Lu

    Full Text Available BACKGROUND: It has been documented all-trans retinoic acid (atRA promotes the development of TGF-β-induced CD4(+Foxp3(+ regulatory T cells (iTreg that play a vital role in the prevention of autoimmune responses, however, molecular mechanisms involved remain elusive. Our objective, therefore, was to determine how atRA promotes the differentiation of iTregs. METHODOLOGY/PRINCIPAL FINDINGS: Addition of atRA to naïve CD4(+CD25(- cells stimulated with anti-CD3/CD28 antibodies in the presence of TGF-β not only increased Foxp3(+ iTreg differentiation, but maintained Foxp3 expression through apoptosis inhibition. atRA/TGF-β-treated CD4(+ cells developed complete anergy and displayed increased suppressive activity. Infusion of atRA/TGF-β-treated CD4(+ cells resulted in the greater effects on suppressing symptoms and protecting the survival of chronic GVHD mice with typical lupus-like syndromes than did CD4(+ cells treated with TGF-β alone. atRA did not significantly affect the phosphorylation levels of Smad2/3 and still promoted iTreg differentiation in CD4(+ cells isolated from Smad3 KO and Smad2 conditional KO mice. Conversely, atRA markedly increased ERK1/2 activation, and blockade of ERK1/2 signaling completely abolished the enhanced effects of atRA on Foxp3 expression. Moreover, atRA significantly increased histone methylation and acetylation within the promoter and conserved non-coding DNA sequence (CNS elements at the Foxp3 gene locus and the recruitment of phosphor-RNA polymerase II, while DNA methylation in the CNS3 was not significantly altered. CONCLUSIONS/SIGNIFICANCE: We have identified the cellular and molecular mechanism(s by which atRA promotes the development and maintenance of iTregs. These results will help to enhance the quantity and quality of development of iTregs and may provide novel insights into clinical cell therapy for patients with autoimmune diseases and those needing organ transplantation.

  18. Potent and Selective KDM5 Inhibitor Stops Cellular Demethylation of H3K4me3 at Transcription Start Sites and Proliferation of MM1S Myeloma Cells.

    Science.gov (United States)

    Tumber, Anthony; Nuzzi, Andrea; Hookway, Edward S; Hatch, Stephanie B; Velupillai, Srikannathasan; Johansson, Catrine; Kawamura, Akane; Savitsky, Pavel; Yapp, Clarence; Szykowska, Aleksandra; Wu, Na; Bountra, Chas; Strain-Damerell, Claire; Burgess-Brown, Nicola A; Ruda, Gian Filippo; Fedorov, Oleg; Munro, Shonagh; England, Katherine S; Nowak, Radoslaw P; Schofield, Christopher J; La Thangue, Nicholas B; Pawlyn, Charlotte; Davies, Faith; Morgan, Gareth; Athanasou, Nick; Müller, Susanne; Oppermann, Udo; Brennan, Paul E

    2017-03-16

    Methylation of lysine residues on histone tail is a dynamic epigenetic modification that plays a key role in chromatin structure and gene regulation. Members of the KDM5 (also known as JARID1) sub-family are 2-oxoglutarate (2-OG) and Fe(2+)-dependent oxygenases acting as histone 3 lysine 4 trimethyl (H3K4me3) demethylases, regulating proliferation, stem cell self-renewal, and differentiation. Here we present the characterization of KDOAM-25, an inhibitor of KDM5 enzymes. KDOAM-25 shows biochemical half maximal inhibitory concentration values of <100 nM for KDM5A-D in vitro, high selectivity toward other 2-OG oxygenases sub-families, and no off-target activity on a panel of 55 receptors and enzymes. In human cell assay systems, KDOAM-25 has a half maximal effective concentration of ∼50 μM and good selectivity toward other demethylases. KDM5B is overexpressed in multiple myeloma and negatively correlated with the overall survival. Multiple myeloma MM1S cells treated with KDOAM-25 show increased global H3K4 methylation at transcriptional start sites and impaired proliferation. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Statistics On Title II Direct Payments To Claimant Representatives

    Data.gov (United States)

    Social Security Administration — Every person has the right to be represented by an attorney or other representative while pursuing a claim or other rights. This dataset contains data around Title...

  20. VT Biodiversity Project - Representative Landscapes in Vermont polygons

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This coverage represents the results of an analysis of landscape diversity in Vermont. Polygons in the dataset represent as much as possible (in a...

  1. Demethylation of IGFBP5 by Histone Demethylase KDM6B Promotes Mesenchymal Stem Cell-Mediated Periodontal Tissue Regeneration by Enhancing Osteogenic Differentiation and Anti-Inflammation Potentials.

    Science.gov (United States)

    Liu, Dayong; Wang, Yuejun; Jia, Zhi; Wang, Liping; Wang, Jinsong; Yang, Dongmei; Song, Jianqiu; Wang, Songlin; Fan, Zhipeng

    2015-08-01

    Mesenchymal stem cell (MSC)-mediated periodontal tissue regeneration is considered a promising method for periodontitis treatment. The molecular mechanism underlying directed differentiation and anti-inflammatory actions remains unclear, thus limiting potential MSC application. We previously found that insulin-like growth factor binding protein 5 (IGFBP5) is highly expressed in dental tissue-derived MSCs compared with in non-dental tissue-derived MSCs. IGFBP5 is mainly involved in regulating biological activity of insulin-like growth factors, and its functions in human MSCs and tissue regeneration are unclear. In this study, we performed gain- and loss-of-function assays to test whether IGFBP5 could regulate the osteogenic differentiation and anti-inflammatory potential in MSCs. We found that IGFBP5 expression was upregulated upon osteogenic induction, and that IGFBP5 enhanced osteogenic differentiation in MSCs. We further showed that IGFBP5 prompted the anti-inflammation effect of MSCs via negative regulation of NFκB signaling. Depletion of the histone demethylase lysine (K)-specific demethylase 6B (KDM6B) downregulated IGFBP5 expression by increasing histone K27 methylation in the IGFBP5 promoter. Moreover, IGFBP5 expression in periodontal tissues was downregulated in individuals with periodontitis compared with in healthy people, and IGFBP5 enhanced MSC-mediated periodontal tissue regeneration and alleviated local inflammation in a swine model of periodontitis. In conclusion, our present results reveal a new function for IGFBP5, provide insight into the mechanism underlying the directed differentiation and anti-inflammation capacities of MSCs, and identify a potential target mediator for improving tissue regeneration.

  2. 42 CFR 422.1010 - Authority of representatives.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Authority of representatives. 422.1010 Section 422.1010 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES....1010 Authority of representatives. (a) A representative appointed and qualified in accordance with...

  3. 42 CFR 423.1010 - Authority of representatives.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Authority of representatives. 423.1010 Section 423.1010 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Penalties § 423.1010 Authority of representatives. (a) A representative appointed and qualified...

  4. 40 CFR 197.31 - What is a representative volume?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false What is a representative volume? 197... a representative volume? (a) It is the volume of ground water that would be withdrawn annually from... Yucca Mountain disposal system that will be in the representative volume. The DOE must then use...

  5. 22 CFR 23.4 - Representative value in exchange.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Representative value in exchange. 23.4 Section 23.4 Foreign Relations DEPARTMENT OF STATE FEES AND FUNDS FINANCE AND ACCOUNTING § 23.4 Representative value in exchange. Representative value in exchange for the collection of a fee means...

  6. 20 CFR 266.7 - Accountability of a representative payee.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Accountability of a representative payee. 266.7 Section 266.7 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD RETIREMENT ACT REPRESENTATIVE PAYMENT § 266.7 Accountability of a representative payee. (a) A...

  7. Oscillatory responses representing differential auditory processing in sleep.

    Science.gov (United States)

    Karakaş, Sirel; Cakmak, Emine D; Bekçi, Belma; Aydin, Hamdullah

    2007-07-01

    The goal of the study was to investigate the contribution of the delta and theta responses to the peaks on the event-related potential waveform and specifically to find the possible cognitive correlates of these oscillatory responses in rapid eye movements (REM) sleep and Stage 2 (spindle sleep), Stage 3 (light sleep) and Stage 4 (deep sleep; slow wave sleep) of non-REM sleep. Data on overnight sleep was acquired from 12 healthy, young adult, volunteer males; those on awake stage were obtained from 19 matched males. Brain activity was obtained in response to auditory stimuli (2000 Hz deviant and 1000 Hz standard stimuli: 65 dB, 10 ms r/f time, 50 ms duration) under passive oddball paradigm in sleep, active and passive oddball (OB-a, OB-p, respectively) paradigms in wakefulness. The effect of the experimental variables (stimulus type, sleep stage) was studied using 2 x 4 analysis of variance for repeated measures and stepwise multiple regression analysis. Overall, three types of configurations were obtained for the oscillatory responses which varied according to sleep stage and stimulus type: Large amplitude, differentiated delta and distinct theta response of long duration; distinct theta response with short duration; distinct delta response. As in wakefulness, the morphology of the time-domain peaks was found to be due to the superposition of the delta and theta responses. The configuration in REM resembled the responses to the OB-p paradigm and that NREM stages resembled the responses to the OB-a paradigm in wakefulness. Auditory information processing selectively varied according to sleep stages and took longer in sleep. Comparable peaks were obtained at longer latencies and later components appeared that did not exist under wakefulness. With respect to the long-duration theta activity, and greater differentiation between the deviant- and standard-elicited stimuli, Stage 2 appeared to represent the more effortful cognitive processing.

  8. Multi-mode entangled states represented as Grassmannian polynomials

    Science.gov (United States)

    Maleki, Y.

    2016-09-01

    We introduce generalized Grassmannian representatives of multi-mode state vectors. By implementing the fundamental properties of Grassmann coherent states, we map the Hilbert space of the finite-dimensional multi-mode states to the space of some Grassmannian polynomial functions. These Grassmannian polynomials form a well-defined space in the framework of Grassmann variables; namely Grassmannian representative space. Therefore, a quantum state can be uniquely defined and determined by an element of Grassmannian representative space. Furthermore, the Grassmannian representatives of some maximally entangled states are considered, and it is shown that there is a tight connection between the entanglement of the states and their Grassmannian representatives.

  9. A High-Throughput Mass Spectrometry Assay Coupled with Redox Activity Testing Reduces Artifacts and False Positives in Lysine Demethylase Screening.

    Science.gov (United States)

    Wigle, Tim J; Swinger, Kerren K; Campbell, John E; Scholle, Michael D; Sherrill, John; Admirand, Elizabeth A; Boriack-Sjodin, P Ann; Kuntz, Kevin W; Chesworth, Richard; Moyer, Mikel P; Scott, Margaret Porter; Copeland, Robert A

    2015-07-01

    Demethylation of histones by lysine demethylases (KDMs) plays a critical role in controlling gene transcription. Aberrant demethylation may play a causal role in diseases such as cancer. Despite the biological significance of these enzymes, there are limited assay technologies for study of KDMs and few quality chemical probes available to interrogate their biology. In this report, we demonstrate the utility of self-assembled monolayer desorption/ionization (SAMDI) mass spectrometry for the investigation of quantitative KDM enzyme kinetics and for high-throughput screening for KDM inhibitors. SAMDI can be performed in 384-well format and rapidly allows reaction components to be purified prior to injection into a mass spectrometer, without a throughput-limiting liquid chromatography step. We developed sensitive and robust assays for KDM1A (LSD1, AOF2) and KDM4C (JMJD2C, GASC1) and screened 13,824 compounds against each enzyme. Hits were rapidly triaged using a redox assay to identify compounds that interfered with the catalytic oxidation chemistry used by the KDMs for the demethylation reaction. We find that overall this high-throughput mass spectrometry platform coupled with the elimination of redox active compounds leads to a hit rate that is manageable for follow-up work.

  10. Neurodynamics in the Sensorimotor Loop: Representing Behavior Relevant External Situations.

    Science.gov (United States)

    Pasemann, Frank

    2017-01-01

    In the context of the dynamical system approach to cognition and supposing that brains or brain-like systems controlling the behavior of autonomous systems are permanently driven by their sensor signals, the paper approaches the question of neurodynamics in the sensorimotor loop in a purely formal way. This is carefully done by addressing the problem in three steps, using the time-discrete dynamics of standard neural networks and a fiber space representation for better clearness. Furthermore, concepts like meta-transients, parametric stability and dynamical forms are introduced, where meta-transients describe the effect of realistic sensor inputs, parametric stability refers to a class of sensor inputs all generating the "same type" of dynamic behavior, and a dynamical form comprises the corresponding class of parametrized dynamical systems. It is argued that dynamical forms are the essential internal representatives of behavior relevant external situations. Consequently, it is suggested that dynamical forms are the basis for a memory of these situations. Finally, based on the observation that not all brain process have a direct effect on the motor activity, a natural splitting of neurodynamics into vertical (internal) and horizontal (effective) parts is introduced.

  11. Representative Delay Measurements (RDM: Facing the Challenge of Modern Networks

    Directory of Open Access Journals (Sweden)

    Joachim Fabini

    2015-02-01

    Full Text Available Network access technologies have evolved significantly in the last years. They deploy novel mechanisms like reactive capacity allocation and time-slotted operation to optimize overall network capacity. From a single node's perspective, such optimizations decrease network determinism and measurement repeatability. Evolving application fields like machine to machine (M2M communications or real-time gaming often have strict real-time requirements to operate correctly. Highly accurate delay measurements are necessary to monitor network compliance with application demands or to detect deviations of normal network behavior, which may be caused by network failures, misconfigurations or attacks. This paper analyzes factors that challenge active delay measurements in modern networks. It introduces the Representative Delay Measurement tool (RDM that addresses these factors and proposes solutions that conform to requirements of the recently published RFC7312. Delay measurement results acquired using RDM in live networks confirm that advanced measurement methods can significantly improve the quality of measurement samples by isolating systematic network behavior. The resulting high-quality samples are one prerequisite for accurate statistics that support proper operation of subsequent algorithms and applications.

  12. Up-regulation of HLA class-I antigen expression and antigen-specific CTL response in cervical cancer cells by the demethylating agent hydralazine and the histone deacetylase inhibitor valproic acid

    Directory of Open Access Journals (Sweden)

    Lizano-Soberón Marcela

    2006-12-01

    Full Text Available Abstract Background DNA hypermethylation and histone deacetylation are epigenetic events that contribute to the absence or downregulated expression of different components of the tumor recognition complex. These events affect the processing and presentation of antigenic peptides to CTLs by HLA class-I molecules. In this work evaluated the effect of the DNA hypomethylating agent hydralazine and the histone deacetylase inhibitor valproic acid, on the expression of HLA class-I molecules and on the antigen-specific immune recognition of cervical cancer cells. Methods Cell lines C33A (HPV-, CaSki (HPV-16+ and MS751 (HPV-18+ were treated with hydralazine and valproic acid to assess the expression of HLA class-I molecules by flow cytometry and RT-PCR. Promoter methylation of HLA class-I -A, -B and C, was also evaluated by Methylation-Specific PCR. Primary cervical tumors of four HLA-A*0201 allele patients were typed for HPV and their CTL's stimulated in vitro with the T2 cell line previously loaded with 50 μM of the HPV peptides. Cytotoxicity of stimulated CTL's was assayed against Caski and MS751 cells pre-treated with hydralazine and valproic acid. Results Valproic acid and hydralazine/valproic acid up-regulated the constitutive HLA class-I expression as evaluated by flow cytometry and RT-PCR despite constitutive promoter demethylation at these loci. Hydralazine and valproic acid in combination but no IFN-gamma hyperacetylated histone H4 as evaluated by ChiP assay. The antigenic immune recognition of CaSki and MS751 cells by CTLs specific to HPV-16/18 E6 and E7-derived epitopes, was increased by VA and H/VA and the combination of H/VA/IFN-gamma. Conclusion These results support the potential use of hydralazine and valproic acid as an adjuvant for immune intervention in cervical cancer patients whenever clinical protocols based on tumor antigen recognition is desirable, like in those cases where the application of E6 and E7 based therapeutic vaccines

  13. [Quantitative method of representative contaminants in groundwater pollution risk assessment].

    Science.gov (United States)

    Wang, Jun-Jie; He, Jiang-Tao; Lu, Yan; Liu, Li-Ya; Zhang, Xiao-Liang

    2012-03-01

    In the light of the problem that stress vulnerability assessment in groundwater pollution risk assessment is lack of an effective quantitative system, a new system was proposed based on representative contaminants and corresponding emission quantities through the analysis of groundwater pollution sources. And quantitative method of the representative contaminants in this system was established by analyzing the three properties of representative contaminants and determining the research emphasis using analytic hierarchy process. The method had been applied to the assessment of Beijing groundwater pollution risk. The results demonstrated that the representative contaminants hazards greatly depended on different research emphasizes. There were also differences between the sequence of three representative contaminants hazards and their corresponding properties. It suggested that subjective tendency of the research emphasis had a decisive impact on calculation results. In addition, by the means of sequence to normalize the three properties and to unify the quantified properties results would zoom in or out of the relative properties characteristic of different representative contaminants.

  14. Using stories to disseminate research: the attributes of representative stories.

    Science.gov (United States)

    Steiner, John F

    2007-11-01

    When researchers communicate their findings to patients, clinicians, policy-makers, or media, they may find it helpful to supplement quantitative data with stories about individuals who represent themes in their research. Whether such stories are gathered during the research itself or identified from other sources, researchers must develop strategies for assessing their representativeness. This paper proposes 5 attributes of representative stories: (1) expression of important themes in the research, (2) explicit location in the "distribution" of stories that exemplify the theme, (3) verifiability, (4) acknowledgment of uncertainty, and (5) compelling narration. This paper summarizes research on substance abuse among physicians, and uses these 5 attributes to assess the representativeness of a published case report and a fictional short story about addicted physicians. While neither story is fully representative of the research, the process of evaluating these stories illustrates an approach to identifying representative stories for use in disseminating research.

  15. High School Students' perception of University Students as STEM representatives

    DEFF Research Database (Denmark)

    Poulsen, Eva Lykkegaard

    2012-01-01

    . Some representatives transmit information and are thereby definers, whereas other representatives illustrates as personal examples and are thereby models. This study focuses on high school students’ views on STEM representatives and the impact these representatives have on the high school students......The Danish government has an ambition to recruit more high school students into STEM educations (science, technology, engineering and/or mathematics). The students’ choice of further education is based on the people and jobs they have knowledge of. Therefore, to recruit more students into STEM...... studies, it is important to introduce high school students to good STEM representatives to make possible the development of potential STEM identities. A potential identity within a specific subject area relies on at least a situation bound relationship to the subject area or the person representing it...

  16. High School Students' Perception of University Students as STEM Representatives

    DEFF Research Database (Denmark)

    Poulsen, Eva Lykkegaard

    . Some representatives transmit infor-mation and are thereby definers, whereas other representatives illustrates as personal examples and are thereby models. This study focuses on high school students’ views on STEM representatives and the impact these representatives have on the high school students......The Danish government has an ambition to recruit more high school students into STEM edu-cations (science, technology, engineering and/or mathematics). The students’ choice of further education is based on the people and jobs they have knowledge of. Therefore, to recruit more students into STEM...... studies, it is important to introduce high school students to good STEM representatives to make possible the development of potential STEM identities. A potential identity within a specific subject area relies on at least a situation bound relation-ship to the subject area or the person representing it...

  17. Histone deacetylase inhibitors upregulate Rap1GAP and inhibit Rap activity in thyroid tumor cells.

    Science.gov (United States)

    Dong, Xiaoyun; Korch, Christopher; Meinkoth, Judy L

    2011-06-01

    Increases in Rap activity have been associated with tumor progression. Although activating mutations in Rap have not been described, downregulation of Rap1GAP is frequent in human tumors including thyroid carcinomas. In this study, we explored whether endogenous Rap1GAP expression could be restored to thyroid tumor cells. The effects of deacetylase inhibitors and a demethylating agent, individually and in combination, were examined in four differentiated and six anaplastic thyroid carcinoma (ATC) cell lines. Treatment with the structurally distinct histone deacetylase (HDAC) inhibitors, sodium butyrate and trichostatin A, increased Rap1GAP expression in all the differentiated thyroid carcinoma cell lines and in four of the six ATC cell lines. The demethylating agent, 5-aza-deoxycytidine, restored Rap1GAP expression in one anaplastic cell line and enhanced the effects of HDAC inhibitors in a second anaplastic cell line. Western blotting indicated that Rap2 was highly expressed in human thyroid cancer cells. Importantly, treatment with HDAC inhibitors impaired Rap2 activity in both differentiated and anaplastic tumor cell lines. The mechanism through which Rap activity is repressed appears to entail effects on the expression of multiple Rap regulators, including RapGEFs and RapGAPs. These results suggest that HDAC inhibitors may provide a tractable approach to impair Rap activity in human tumor cells.

  18. 42 CFR 102.44 - Representatives of requesters.

    Science.gov (United States)

    2010-10-01

    ... COMPENSATION PROGRAM Procedures for Filing Request Packages § 102.44 Representatives of requesters. (a) Persons other than a requester (e.g., a lawyer, guardian, friend) may file a Request Package on a requester's behalf as his or her representative. A requester need not use the services of a lawyer to secure benefits...

  19. A geometric language for representing structure in polyphonic music

    DEFF Research Database (Denmark)

    Meredith, David

    2012-01-01

    is represented as a set of multidimensional points, generated by performing transformations on component patterns. The language introduces the concept of a periodic mask, a generalisation of Deutsch and Feroe’s notion of a pitch alphabet, that can be applied to any dimension of a geometric representation......, allowing for both rhythms and pitch collections to be represented parsimoniously in a uniform way....

  20. 16 CFR 460.6 - “Representative thickness” testing.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false âRepresentative thicknessâ testing. 460.6 Section 460.6 Commercial Practices FEDERAL TRADE COMMISSION TRADE REGULATION RULES LABELING AND ADVERTISING OF HOME INSULATION § 460.6 “Representative thickness” testing. All tests except aluminum...

  1. State Tax Capacity and the Representative Tax System.

    Science.gov (United States)

    Lucke, Robert B.

    1984-01-01

    Discusses the merit of using the Representative Tax System to measure state fiscal capacity instead of the traditional measure of per capita income. The conclusion is that the Representative Tax System can play a major role in determining the allocation of federal grants. (MJL)

  2. 20 CFR 725.363 - Qualification of representative.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Qualification of representative. 725.363... MINE HEALTH AND SAFETY ACT OF 1969, AS AMENDED CLAIMS FOR BENEFITS UNDER PART C OF TITLE IV OF THE....363 Qualification of representative. (a) Attorney. Any attorney in good standing who is admitted...

  3. Calls to Teen Line: Representative Concerns of Adolescents.

    Science.gov (United States)

    Boehm, Kathryn E.; Schondel, Connie K.; Ivoska, William J.; Marlowe, Alison L.; Manke-Mitchell, Laurie

    1998-01-01

    Study examines whether the concerns of teenagers calling a peer listening service are representative of the concerns of teenagers in the area served. Results indicate that students' biggest concerns involve family problems, peer relationships, self-esteem, and school problems. Concludes that calls to the teen line are representative. (Author/GCP)

  4. 40 CFR Appendix I to Part 261 - Representative Sampling Methods

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Representative Sampling Methods I...—Representative Sampling Methods The methods and equipment used for sampling waste materials will vary with the form and consistency of the waste materials to be sampled. Samples collected using the...

  5. Dontion From CCPIT Overseas Representative Offices To Earthquake

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@After the strong earthquake centered in Wenchuan County in the Southwestern Chinese Sichuan Province took place,the CCPIT Overseas Representative Offices immediately responding to the call of the CPC Central Committee,the State Council and following the instruction of CCPIT concerning disaster relief work,vigororsly organized.Below are the statistics of donation from partial overseas representative offices by May 19.

  6. 20 CFR 211.5 - Employee representative compensation.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Employee representative compensation. 211.5... CREDITABLE RAILROAD COMPENSATION § 211.5 Employee representative compensation. All payments made by a railway... office he occupies with such organization are creditable as compensation, including payments made...

  7. 37 CFR 10.84 - Representing a client zealously.

    Science.gov (United States)

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Representing a client... Office Code of Professional Responsibility § 10.84 Representing a client zealously. (a) A practitioner shall not intentionally: (1) Fail to seek the lawful objectives of a client through reasonably available...

  8. 37 CFR 1.34 - Acting in a representative capacity.

    Science.gov (United States)

    2010-07-01

    ... capacity. 1.34 Section 1.34 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE... of Application and Appointment of Attorney Or Agent § 1.34 Acting in a representative capacity. When a patent practitioner acting in a representative capacity appears in person or signs a paper...

  9. 14 CFR 183.31 - Designated manufacturing inspection representatives.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Designated manufacturing inspection representatives. 183.31 Section 183.31 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF...: Privileges § 183.31 Designated manufacturing inspection representatives. A designated...

  10. 22 CFR 41.25 - NATO representatives, officials, and employees.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false NATO representatives, officials, and employees... UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Foreign Government Officials § 41.25 NATO representatives, officials, and employees. (a) Classification. An alien shall be classified under the symbol...

  11. Family representative payeeship and violence risk in severe mental illness.

    Science.gov (United States)

    Elbogen, Eric B; Swanson, Jeffrey W; Swartz, Marvin S; Van Dorn, Richard

    2005-10-01

    Although representative payeeship is prevalent among people with mental illness and shows promise to positively influence clinically relevant outcomes, research also suggests this legal mechanism could be implemented in ways that are problematic. The current study examined whether family representative payeeship was associated with elevated risk of family violence perpetrated by persons with severe mental illness (SMI). Data were collected every 4 months for 1 year in structured interviews with N = 245 persons with SMI who received disability benefits. Multivariate analyses showed that substance abuse, history of violence, frequency of family contact, and family representative payeeship were associated with elevated odds of family violence. Analyses also showed family contact and family representative payeeship had a cumulative effect on increasing the predicted probability of family violence (controlling for covariates such as violence history and substance abuse). The data shed light on the potential for family representative payeeship to be associated with increased risk of interpersonal conflict and violence in SMI.

  12. Improvement of Physical Decline Through Combined Effects of Muscle Enhancement and Mitochondrial Activation by a Gastric Hormone Ghrelin in Male 5/6Nx CKD Model Mice.

    Science.gov (United States)

    Tamaki, Masanori; Hagiwara, Aika; Miyashita, Kazutoshi; Wakino, Shu; Inoue, Hiroyuki; Fujii, Kentaro; Fujii, Chikako; Sato, Masaaki; Mitsuishi, Masanori; Muraki, Ayako; Hayashi, Koichi; Doi, Toshio; Itoh, Hiroshi

    2015-10-01

    Because a physical decline correlates with an increased risk of a wide range of disease and morbidity, an improvement of physical performance is expected to bring significant clinical benefits. The primary cause of physical decline in 5/6 nephrectomized (5/6Nx) chronic kidney disease model mice has been regarded as a decrease in muscle mass; however, our recent study showed that a decrease in muscle mitochondria plays a critical role. In the present study, we examined the effects of a gastric hormone ghrelin, which has been reported to promote muscle mitochondrial oxidation, on the physical decline in the chronic kidney disease model mice, focusing on the epigenetic modulations of a mitochondrial activator gene, peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α). Ghrelin treatment improved a decline in exercise endurance of 5/6Nx mice, associated with an increase in both of the muscle mass and mitochondrial amount. The expression level of PGC-1α was decreased in the skeletal muscle of 5/6Nx mice, which was associated with an increase in the methylation ratio of the cytosine residue at 260 base pairs upstream of the initiation point. Conversely, ghrelin treatment de-methylated the cytosine residue and increased the expression of PGC-1α. A representative muscle anabolic factor, IGF-1, did not affect the expression of PGC-1α and muscle mitochondrial amount, although it increased muscle mass. As a result, IGF-1 treatment in 5/6Nx mice did not increase the decreased exercise endurance as effectively as ghrelin treatment did. These findings indicate an advantage of ghrelin treatment for a recovery of physical decline.

  13. 5-氮杂-2′-脱氧胞苷诱导肝癌细胞株SLIT2基因去甲基化的实验研究%5-Aza-CdR induces demethylation of SLIT2 gene in human hepatoma cell lines

    Institute of Scientific and Technical Information of China (English)

    李培坤; 耿小平

    2015-01-01

    Objective To investigate the effect of 5-Aza-CdR on methylation state and transcription of SLIT2 gene in hepatocellular carcinoma cell lines,and to discuss mechanism of SLIT2 gene silencing in 5 human hepatoma cell lines as well as the effect of demethylation agent on its expression.Methods All cell lines of SUN449,BEL-7402,SMMC-7721,Hep3B and HepG2 were cultured in vitro and treated with 10 mmol/L 5-Aza-CdR.The promoter methylation state of SLIT2 gene and the mRNA expression of SLIT2 gene in the 5 hepatoma cell lines before and after 5-Aza-CdR treatment were detected by methylation-specific PCP (MSP)and reverse transcription-PCR (RT-PCR),re-spectively.Results Promoter hypermethylation of SLIT2 gene was detected in all 5 hepatoma cell lines and SLIT2 gene was expressed at a low level before 5-Aza-CdR treatment.After treated with demethylation agent 5-Aza-CdR,the promoter region of SLIT2 gene exhibited dem-ethylation state,and gene expression increased significantly at mRNA level.Conclusion Promoter hypermethylation is a main mechanism of SLIT2 gene silencing in 5 human hepatoma cell lines,and could be reversed by demethylation agent 5-Aza-CdR. carcinoma cell lines,and to discuss mechanism of SLIT2 gene silencing in 5 human hepatoma cell lines as well as the effect of demethylation agent on its expression.Methods All cell lines of SUN449,BEL-7402,SMMC-7721,Hep3B and HepG2 were cultured in vitro and treated with 10 mmol/L 5-Aza-CdR.The promoter methylation state of SLIT2 gene and the mRNA expression of SLIT2 gene in the 5 hepatoma cell lines before and after 5-Aza-CdR treatment were detected by methylation-specific PCP (MSP)and reverse transcription-PCR (RT-PCR),re-spectively.Results Promoter hypermethylation of SLIT2 gene was detected in all 5 hepatoma cell lines and SLIT2 gene was expressed at a low level before 5-Aza-CdR treatment.After treated with demethylation agent 5-Aza-CdR,the promoter region of SLIT2 gene exhibited dem-ethylation state,and gene expression

  14. 7 CFR 1.610 - Who may represent a party, and what requirements apply to a representative?

    Science.gov (United States)

    2010-01-01

    ... ADMINISTRATIVE REGULATIONS Conditions in FERC Hydropower Licenses Hearing Process § 1.610 Who may represent a... may either represent himself or herself in the hearing process under this subpart or authorize an... documents under § 1.611; (2) Include the name and address of the person on whose behalf the appearance is...

  15. Choosing a Group Representative : The Impact of Perceived Organizational Support on the Preferences for Deviant Representatives in Work Negotiations

    NARCIS (Netherlands)

    Demoulin, Stephanie; Teixeira, Catia Pinto; Gillis, Celine; Goldoni, Edwine; Stinglhamber, Florence

    2016-01-01

    Group representative selection in negotiation is a topic that has only recently attracted researchers' attention. This article focuses on workplace negotiations and examines how employees' selection of representatives depends on their level of perceived organizational support (POS). We predict and s

  16. Choosing a Group Representative : The Impact of Perceived Organizational Support on the Preferences for Deviant Representatives in Work Negotiations

    NARCIS (Netherlands)

    Demoulin, Stephanie; Teixeira, Catia Pinto; Gillis, Celine; Goldoni, Edwine; Stinglhamber, Florence

    2016-01-01

    Group representative selection in negotiation is a topic that has only recently attracted researchers' attention. This article focuses on workplace negotiations and examines how employees' selection of representatives depends on their level of perceived organizational support (POS). We predict and s

  17. Administrative Circular No. 13 (Rev. 3) - Guarantees for representatives of the personnel

    CERN Multimedia

    2014-01-01

    Administrative Circular No. 13 (Rev. 3) entitled “Guarantees for representatives of the personnel”, approved by the Director-General following discussion at the Standing Concertation Committee meeting of 5 December 2013 and entering into force on 1 January 2014, is available on the intranet site of the Human Resources Department (see here).   This circular is applicable to all members of the personnel. It cancels and replaces Administrative Circular No. 13 (Rev. 2) entitled “Guarantees for members of the personnel holding representative office” of November 1992. The circular was revised in order to adapt the time given to the representatives of the personnel to perform their elective mandate and to ensure more transparency in their activities, by indicating, inter alia, the percentage of time worked in the framework of their mandate, as well as the training, activities and ensuing results. Department Head Office HR Department

  18. Direct and Representative Democracy - Supplementing, not Excluding Each Other

    DEFF Research Database (Denmark)

    Svensson, Palle

    2007-01-01

      This paper presents and discuses four main arguments for and against direct democracy, popular initiatives and referendums: (1) higher responsiveness versus lesser quality; (2) higher popular responsibility versus weaker representatives; (3) higher popular participation versus deeper conflicts...

  19. Statement of Bureau representative [template] [Laguna Atascosa National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a template used for the statement of the bureau representative and the public hearing for the Laguna Atascosa National Wildlife Refuge Wilderness...

  20. Allegheny County Pennsylvania House of Representatives District Boundaries

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset demarcates the Pennsylvania House of Representatives district boundaries within Allegheny County. If viewing this description on the Western...

  1. [Technical Representative - Monthly PMC Issues Reports : Rocky Mountain Arsenal NWR

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This collection of documents contains the Monthly PMC Issues reports for the Rocky Mountain Arsenal compiled by the Technical Representative. Reports in this...

  2. Sample representativeness verification of the FADN CZ farm business sample

    Directory of Open Access Journals (Sweden)

    Marie Prášilová

    2011-01-01

    Full Text Available Sample representativeness verification is one of the key stages of statistical work. After having joined the European Union the Czech Republic joined also the Farm Accountancy Data Network system of the Union. This is a sample of bodies and companies doing business in agriculture. Detailed production and economic data on the results of farming business are collected from that sample annually and results for the entire population of the country´s farms are then estimated and assessed. It is important hence, that the sample be representative. Representativeness is to be assessed as to the number of farms included in the survey and also as to the degree of accordance of the measures and indices as related to the population. The paper deals with the special statistical techniques and methods of the FADN CZ sample representativeness verification including the necessary sample size statement procedure. The Czech farm population data have been obtained from the Czech Statistical Office data bank.

  3. 42 CFR 423.2272 - Licensing of marketing representatives and confirmation of marketing resources.

    Science.gov (United States)

    2010-10-01

    ... activities (as defined in the Medicare Marketing Guidelines) in that State, and whom the sponsor has informed... 42 Public Health 3 2010-10-01 2010-10-01 false Licensing of marketing representatives and confirmation of marketing resources. 423.2272 Section 423.2272 Public Health CENTERS FOR MEDICARE &...

  4. 42 CFR 422.2272 - Licensing of marketing representatives and confirmation of marketing resources.

    Science.gov (United States)

    2010-10-01

    ... activities (as defined in the Medicare Marketing Guidelines) in that State, and whom the organization has... 42 Public Health 3 2010-10-01 2010-10-01 false Licensing of marketing representatives and confirmation of marketing resources. 422.2272 Section 422.2272 Public Health CENTERS FOR MEDICARE &...

  5. Designation of Contracting Officers Representatives and Oversight Framework Could Be Improved for Contracts in Afghanistan

    Science.gov (United States)

    2016-08-30

    activities involved. 22 DFARS Procedures, Guidance , and Information 201.6, “ Career Development, Contracting Authority, and Responsibilities...did not follow Defense acquisition guidelines. • An in-country representative for a U.S. Naval Sea Systems contract did not receive guidance on...Recommendations We recommend that officials from Defense Procurement and Acquisition Policy, Under Secretary of Defense for Acquisition, Technology

  6. Elections for staff representatives – Join, commit and vote!

    CERN Document Server

    Staff Association

    2015-01-01

    The Staff Council is a statutory body representing collectively in the area of employment conditions all CERN staff members (MPE and MPA), as well as the pensioners, former Cernois. The Staff Council is the supreme representative body of the CERN staff and pensioners, which defines the main lines of the policy of the Staff Association. The Staff Council is composed of staff representatives (45 seats to represent staff members, and 5 for representing fellows and associate members), as well as delegates for pensioners (seven positions), designated by GAC-EPA. Every two years, the Council is renewed through elections. Concerning the 45 delegates representing staff members, all departments have a least two seats allocated, one in career paths AA to D and one in career paths E to H. This guarantees a fair distribution of seats among the various organizational units and career paths. The table below, shows the exact number of delegates per department and career paths. Staff members or fellows who want to participa...

  7. Identification of objective representative scenarios for hazard assessment

    Science.gov (United States)

    Sandri, Laura; Selva, Jacopo; Costa, Antonio

    2016-04-01

    Assessment of volcanic hazards is typically based on one or a few representative eruptive scenarios, meant as specific combinations of a representative eruptive size, intensity, and vent position, selected with subjective criteria neglecting the full intrinsic natural variability characterizing volcanic processes. In common practice, the size and intensity of such scenarios are taken as representative of wider ranges, here termed "size classes". The approach implicitly or explicitly assumes that the inter-size class variability (among different eruptive size classes) is predominant with respect to the intra-size class variability (i.e., the variability inside each range represented by an eruptive size and intensity), the latter assumed as negligible. So far, no quantitative study has been carried out to verify such an assumption. Here, we first adopt a novel statistical strategy, that accounts for the full natural variability, to quantify the Probabilistic Volcanic Hazard Assessment for tephra fallout in the Campania area. Secondly, we compare the results of the new method with those based on few representative scenarios only. On one hand, such comparison allows for determining when the simplified approach is valid, and quantifying the bias introduced in hazard assessment when the full variability is not accounted for. On the other hand, this novel approach opens the way to an objective a posteriori identification of a limited number of representative scenarios, which are necessary when there is no possibility to explore the full variability, as for example for rapid hazard assessment during emergencies, or for short-term hazard assessment.

  8. Heterogeneous researchers in a two-sector representative consumer economy

    Directory of Open Access Journals (Sweden)

    Orlando Gomes

    2006-06-01

    Full Text Available Research activities have uncertain outcomes. The question asked in this paper is whether or not this uncertainty can be a central piece on the explanation of long run consumption growth paths. More specifically, we inquire how the existence of different research projects, with different degrees of uncertainty, contributes to unpredictable consumption growth paths. The proposed scenario is a two-sector representative consumer model with researchers that invest in different innovation projects. There is heterogeneity in terms of risk associated to research programs (researchers invest in projects with the same expected outcome but different volatility. This difference in volatility, combined with an adaptive learning - bounded rationality rule, implies an aggregate index of technology and a consumption growth rate that do not present a predictable pattern over time.As actividades de investigação produzem resultados incertos. A questão colocada neste artigo é se esta incerteza pode ser uma peça central na explicação das trajectórias de crescimento do consumo no longo prazo. Mais especificamente, pergunta-se como a existência de diferentes projectos de investigação, com diferentes graus de incerteza associados, contribui para trajectórias de crescimento do consumo que não são passíveis de previsão. O cenário proposto é um modelo de consumidor representativo de dois sectores com investigadores que investem em diferentes projectos de inovação. Existe heterogeneidade ao nível do risco associado aos programas de investigação (os investigadores investem em projectos com o mesmo resultado esperado mas diferente volatilidade. A diferença na volatilidade, combinada com uma regra de aprendizagem adaptativa - racionalidade limitada, implica um índice agregado de tecnologia e uma taxa de crescimento do consumo que não apresentam um padrão previsível ao longo do tempo.

  9. Early postoperative erythromycin breath test correlates with hepatic cytochrome P4503A activity in liver transplant recipients

    DEFF Research Database (Denmark)

    Schmidt, L E; Olsen, A K; Stentoft, K;

    2001-01-01

    milligram of protein, and the activity determined by testosterone 6beta-hydroxylation ranged from 0.030 to 0.627 nmol per minute per milligram of protein. Significant correlation was demonstrated between the erythromycin breath test and both the erythromycin demethylation (Spearman correlation coefficient......: R = 0.76, R (2) = 0.57; P =.0004) and the testosterone 6beta-hydroxylation (Spearman correlation coefficient: R = 0.79, R (2) = 0.63; P =.0001) assays. The erythromycin breath test also correlated with the CYP3A protein level (Spearman correlation coefficient: R = 0.60, R (2) = 0.36; P =.01...

  10. Selection of Representative Models for Decision Analysis Under Uncertainty

    Science.gov (United States)

    Meira, Luis A. A.; Coelho, Guilherme P.; Santos, Antonio Alberto S.; Schiozer, Denis J.

    2016-03-01

    The decision-making process in oil fields includes a step of risk analysis associated with the uncertainties present in the variables of the problem. Such uncertainties lead to hundreds, even thousands, of possible scenarios that are supposed to be analyzed so an effective production strategy can be selected. Given this high number of scenarios, a technique to reduce this set to a smaller, feasible subset of representative scenarios is imperative. The selected scenarios must be representative of the original set and also free of optimistic and pessimistic bias. This paper is devoted to propose an assisted methodology to identify representative models in oil fields. To do so, first a mathematical function was developed to model the representativeness of a subset of models with respect to the full set that characterizes the problem. Then, an optimization tool was implemented to identify the representative models of any problem, considering not only the cross-plots of the main output variables, but also the risk curves and the probability distribution of the attribute-levels of the problem. The proposed technique was applied to two benchmark cases and the results, evaluated by experts in the field, indicate that the obtained solutions are richer than those identified by previously adopted manual approaches. The program bytecode is available under request.

  11. Representing Topological Relationships Among Heterogeneous Geometry-Collection Features

    Institute of Scientific and Technical Information of China (English)

    Zhi-Nong Zhong; Ning Jing; Luo Chen; Qiu-Yun Wu

    2004-01-01

    Topological relationships between two spatial features represent important knowledge in Geographical Information Systems (GIS). In the last few years, many models that represent topological relationships have been proposed. But these models cannot represent the topological relationships between heterogeneous geometrycollection features, which are composed of different dimensional geometries. In this paper, the formal definition of regular heterogeneous geometrycollection and regularization rules are given. Based on the spatial model, two methods for representing topological relationships between these complex features are proposed. The first method is Dimensionally Extended Nine-Intersection Model Based on Components (DE-9IMBC) that extends Dimensionally Extended Nine-Intersection Model (DE-9IM) and takes into account the topological relationships between components of these complex features. The advantage of DE-9IMBC is that a large number of different topological relationships can be checked. The second method extends the definitions of topological relationships in Open Geodata Interoperability Specification (OpenGIS), and redefines the seven named topological relationships:{Disjoint, Touches, Within, Crosses, Overlaps, Contains and Equal}, to represent the topological relationships between heterogeneous geometrycollection features. It is proven that the seven extended topological relationships are complete and mutually exclusive, and they are suitable for being embedded in spatial query languages.

  12. Representing Topological Relationships Among Heterogeneous Geometry-Collection Features

    Institute of Scientific and Technical Information of China (English)

    Zhi-NongZhong[; NingJing; LuoChen; Qiu-YunWu

    2004-01-01

    Topological relationships between two spatial features represent important knowledge in Geographical Information Systems (GIS). In the last few years, many models that represent topological relationships have been proposed. But these models cannot represent the topological relationships between heterogeneous geometrycollection features, which are composed of different dimensional geometries. In this paper, the formal definition of regular heterogeneous geometrycollection and regularization rules are given. Based on the spatial model, two methods for representing topological relationships between these complex features are proposed. The first method is Dimensionally Extended Nine-Intersection Model Based on Components (DE-9IMBC) that extends Dimensionally Extended Nine-Intersection Model (DE-9IM) and takes into account the topological relationships between components of these complex features. The advantage of DE-9IMBC is that a large number of different topological relationships can be checked. The second method extends the definitions of topological relationships in Open Geodata Interoperability Specification (OpenGIS), and redefines the seven named topological relationships: {Disjoint, Touches, Within, Crosses, Overlaps, Contains and Equal}, to represent the topological relationships between heterogeneous geometrycollection features. It is proven that the seven extended topological relationships are complete and mutually exclusive, and they are suitable for being embedded in spatial query languages.

  13. Associated factors of obesity in Spanish representative samples

    Directory of Open Access Journals (Sweden)

    Rosa M. Ortega Anta

    2013-09-01

    Full Text Available Given the dramatic increase in the prevalence of obesity and the serious health and economic consequences, the scientific community, health professionals and health agencies are looking for the best strategies to prevent/ fight this trend. In order to plan the most appropriate intervention measures the first step is to identify the associated factors of obesity. This paper presents the results of research conducted/coordinated by our research team and promoted by the Spanish Food Safety Agency (AESAN, in the last five years. These studies were focussed on representative samples of the Spanish population, paying attention to the condition of overweight/obesity and their associated factors. The first study, FANPE ("Fuentes alimentarias de nutrientes de la población española" (2009, was centered in 418 adults (18-60 years from 15 provinces (30 sampling points. Its aim was to analyze the dietary sources of nutrients, paying particular attention to sodium. This research showed that the risk of overweight/obesity increases with age, in people who have follow weight control diets, in ex-smokers, married people and those who slept less than 8.5 hours per day, while the risk is lower in women, people who make sport and those with an University degree. It was also found that overweight people had higher sodium intake and urine excretion. Therefore, and having in mind that 88.2% of the subjects took more than 2 g/day of sodium (the maximum recommended, it is advised to lower the sodium intake not only from the health point of view but also as a probably strategy against obesity. The study ALADINO (Estudio de Alimentación, Actividad física, Desarrollo Infantil y Obesidad- Study of the Diet, Physical Activity, Child Development and Obesity (2010-2011 was focused on 7659 children (6-9 years from 19 autonomous communities. We founded a higher percentage of overweight/obesity in boys than in girls, and a significant increase in the figures from the age of 7

  14. Associated factors of obesity in Spanish representative samples.

    Science.gov (United States)

    Ortega Anta, Rosa M; López-Solaber, Ana M; Pérez-Farinós, Napoleón

    2013-09-01

    Given the dramatic increase in the prevalence of obesity and the serious health and economic consequences, the scientific community, health professionals and health agencies are looking for the best strategies to prevent/ fight this trend. In order to plan the most appropriate intervention measures the first step is to identify the associated factors of obesity. This paper presents the results of research conducted/coordinated by our research team and promoted by the Spanish Food Safety Agency (AESAN), in the last five years. These studies were focussed on representative samples of the Spanish population, paying attention to the condition of overweight/obesity and their associated factors. The first study, FANPE ("Fuentes alimentarias de nutrientes de la población española") (2009), was centered in 418 adults (18-60 years) from 15 provinces (30 sampling points). Its aim was to analyze the dietary sources of nutrients, paying particular attention to sodium. This research showed that the risk of overweight/obesity increa ses with age, in people who have follow weight control diets, in ex-smokers, married people and those who slept less than 8.5 hours per day, while the risk is lower in women, people who make sport and those with a University degree. It was also found that overweight people had higher sodium intake and urine excretion. Therefore, and having in mind that 88.2% of the subjects took more than 2 g/day of sodium (the maximum recommended), it is advised to lower the sodium intake not only from the health point of view but also as a probably strategy against obesity. The study ALADINO (Estudio de Alimentación, Actividad física, Desarrollo Infantil y Obesidad--Study of the Diet, Physical Activity, Child Development and Obesity) (2010-2011) was focused on 7659 children (6-9 years) from 19 autonomous communities. We founded a higher percentage of overweight/obesity in boys than in girls, and a significant increase in the figures from the age of 7. Being

  15. Representing female desire within a labial framework of sexuality.

    Science.gov (United States)

    Schiller, Britt-Marie

    2012-12-01

    Sexual experiences, rather than being neutral, are specifically male or female. Yet at present no conceptual framework exists for representing female sexual desire. This has resulted in frequent misrepresentations of female sexual experience. To correct this, a labial framework is proposed, not to replace or oppose a phallic framework, but to exist alongside it. The lips of the mouth and those of the genitals provide a felicitous doubling of sexuality and speech to represent female desire and sexual pleasure as labial. Phallic and labial rhythms are organized differently in sexual arousal and desire, since, as Simone de Beauvoir put it, "Man 'gets stiff,' but woman 'gets wet.'" The labial framework therefore represents female psychosexuality more in terms of "wetware" than of "hardware."

  16. Knowledge environments representing molecular entities for the virtual physiological human.

    Science.gov (United States)

    Hofmann-Apitius, Martin; Fluck, Juliane; Furlong, Laura; Fornes, Oriol; Kolárik, Corinna; Hanser, Susanne; Boeker, Martin; Schulz, Stefan; Sanz, Ferran; Klinger, Roman; Mevissen, Theo; Gattermayer, Tobias; Oliva, Baldo; Friedrich, Christoph M

    2008-09-13

    In essence, the virtual physiological human (VPH) is a multiscale representation of human physiology spanning from the molecular level via cellular processes and multicellular organization of tissues to complex organ function. The different scales of the VPH deal with different entities, relationships and processes, and in consequence the models used to describe and simulate biological functions vary significantly. Here, we describe methods and strategies to generate knowledge environments representing molecular entities that can be used for modelling the molecular scale of the VPH. Our strategy to generate knowledge environments representing molecular entities is based on the combination of information extraction from scientific text and the integration of information from biomolecular databases. We introduce @neuLink, a first prototype of an automatically generated, disease-specific knowledge environment combining biomolecular, chemical, genetic and medical information. Finally, we provide a perspective for the future implementation and use of knowledge environments representing molecular entities for the VPH.

  17. Spatio-temporal representativeness of aerosol remote sensing observations

    Science.gov (United States)

    Schutgens, Nick; Gryspeerdt, Edward; Tsyro, Svetlana; Goto, Daisuke; Watson-Parris, Duncan; Weigum, Natalie; Schulz, Michael; Stier, Philip

    2016-04-01

    One characteristic of remote sensing observations is the strong intermittency with which they observe the same scene. Due to unfavourable conditions (due to e.g. low visible light, cloudiness or high surface albedo), sampling constraints (due to e.g. polar orbits) or instrument malfunction or maintenance, gaps in the observing record of hours to months exist. At the same time, satellite L3 products often are spatial aggregates over considerable distances (e.g. 1 by 1 degree). We study the impact of spatio-temporal sampling of observations on their representativeness: i.e. how well can satellite products represent the large scale (~ 100 by 100 km) aerosol field over periods of days, months, or years. This study was conducted by using diverse global and regional aerosol models as a truth and sub-sample them according to actual observations. In this way, we have been able to study the representativeness of different observing systems like MODIS, CALIOP and AERONET. Monthly and yearly averages allow serious sampling errors, that may still be present in multi-year climatologies due to recurring observing patterns. Even daily averages are affected as diurnal cycles can often not be observed. We discuss the implications these representativeness errors have for e.g. model evaluation or the construction of climatologies. We also assess similar representativeness issues in ground site in-situ observations from e.g. EMEP or IMPROVE and show that satellite datasets have distinct advantages due to their better spatial coverage provided temporal sampling is dealt with properly (i.e. through collocation of datasets). Finally, we briefly introduce a software tool (the Community Intercomparison Suite or CIS) that is designed to improve representativeness of datasets in intercomparion studies through aggregation and collocation of data.

  18. Representing User Navigation in XML Retrieval with Structural Summaries

    DEFF Research Database (Denmark)

    Ali, M. S.; Consens, Mariano P.; Larsen, Birger

    This poster presents a novel way to represent user navigation in XML retrieval using collection statistics from XML summaries. Currently, developing user navigation models in XML retrieval is costly and the models are specific to collected user assessments. We address this problem by proposing...... summary navigation models which describe user navigation in terms of XML summaries. We develop our proposal using assessments collected in the interactive track at INEX 2006. Our preliminary results suggest that summary navigation models can represent user navigation in a way that is e ective...

  19. Closed-set-based Discovery of Representative Association Rules Revisited

    CERN Document Server

    Balcázar, José L

    2010-01-01

    The output of an association rule miner is often huge in practice. This is why several concise lossless representations have been proposed, such as the "essential" or "representative" rules. We revisit the algorithm given by Kryszkiewicz (Int. Symp. Intelligent Data Analysis 2001, Springer-Verlag LNCS 2189, 350-359) for mining representative rules. We show that its output is sometimes incomplete, due to an oversight in its mathematical validation, and we propose an alternative complete generator that works within only slightly larger running times.

  20. Fuel options from microalgae with representative chemical compositions

    Energy Technology Data Exchange (ETDEWEB)

    Feinberg, D. A.

    1984-07-01

    Representative species of microalgae are examined with respect to their reported chemical compositions. Each species is analyzed under a variety of culture conditions, with the objective being to characterize an optimum mixture of fuel products (e.g., methane, ethanol, methylester) which should be produced by the particular species. Historically the emphasis has been on the entire algal cell mass. Using the reported chemical composition for the representative species under specific sets of growth conditions, some conclusions can be drawn about the preferred fuel product conversion routes that could be employed. 10 references, 7 figures, 12 tables.

  1. A computational model of the hippocampus that represents environmental structure and goal location, and guides movement.

    Science.gov (United States)

    Matsumoto, Jumpei; Makino, Yoshinari; Miura, Haruki; Yano, Masafumi

    2011-08-01

    Hippocampal place cells (PCs) are believed to represent environmental structure. However, it is unclear how and which brain regions represent goals and guide movements. Recently, another type of cells that fire around a goal was found in rat hippocampus (we designate these cells as goal place cells, GPCs). This suggests that the hippocampus is also involved in goal representation. Assuming that the activities of GPCs depend on the distance to a goal, we propose an adaptive navigation model. By monitoring the population activity of GPCs, the model navigates to shorten the distance to the goal. To achieve the distance-dependent activities of GPCs, plastic connections are assumed between PCs and GPCs, which are modified depending on two reward-triggered activities: activity propagation through PC-PC network representing the topological environmental structure, and the activity of GPCs with different durations. The former activity propagation is regarded as a computational interpretation of "reverse replay" phenomenon found in rat hippocampus. Simulation results confirm that after reaching a goal only once, the model can navigate to the goal along almost the shortest path from arbitrary places in the environment. This indicates that the hippocampus might play a primary role in the representation of not only the environmental structure but also the goal, in addition to guiding the movement. This navigation strategy using the population activity of GPCs is equivalent to the taxis strategy, the simplest and most basic for biological systems. Our model is unique because this simple strategy allows the model to follow the shortest path in the topological map of the environment.

  2. Party member recruitment and the representativeness of party membership

    DEFF Research Database (Denmark)

    Kosiara-Pedersen, Karina

    Party membership figures are in decline. However, parties are still recruiting party members. Are there any differences in the social and political characteristics of old and new party members? If there is a difference, are new party members more or less representative for party voters than old...

  3. 7 CFR 1212.12 - Importer-Handler Representative.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Importer-Handler Representative. 1212.12 Section 1212... PACKERS AND IMPORTERS RESEARCH, PROMOTION, CONSUMER EDUCATION AND INDUSTRY INFORMATION ORDER Honey Packers and Importers Research, Promotion, Consumer Education, and Industry Information Order...

  4. 48 CFR 801.603-70 - Representatives of contracting officers.

    Science.gov (United States)

    2010-10-01

    ... contractor. (2) The COTR may not re-delegate authority received under this paragraph. (3) The contracting...) Except for a contract for blood, the contracting officer may delegate this authority only to other..., Contracting Authority, and Responsibilities 801.603-70 Representatives of contracting officers. (a) In...

  5. 26 CFR 31.3211-3 - Employee representative supplemental tax.

    Science.gov (United States)

    2010-04-01

    ... (CONTINUED) EMPLOYMENT TAXES AND COLLECTION OF INCOME TAX AT SOURCE EMPLOYMENT TAXES AND COLLECTION OF INCOME TAX AT SOURCE Railroad Retirement Tax Act (Chapter 22, Internal Revenue Code of 1954) Tax on Employee... 26 Internal Revenue 15 2010-04-01 2010-04-01 false Employee representative supplemental tax. 31...

  6. 22 CFR 41.52 - Information media representative.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Information media representative. 41.52 Section 41.52 Foreign Relations DEPARTMENT OF STATE VISAS VISAS: DOCUMENTATION OF NONIMMIGRANTS UNDER THE IMMIGRATION AND NATIONALITY ACT, AS AMENDED Business and Media Visas § 41.52 Information media...

  7. Development of Reasoning Associated with Pictographs: Representing, Interpreting, and Predicting.

    Science.gov (United States)

    Watson, Jane M.; Moritz, Jonathan B.

    2001-01-01

    Proposes a developmental model involving four response levels concerning how students arrange pictures to represent data in a pictograph, how they interpret these pictographs, and how they make predictions based on these pictographs. The model is exemplified by responses from three related interview-based studies. Discusses educational…

  8. 19 CFR 146.2 - Port director as Board representative.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Port director as Board representative. 146.2 Section 146.2 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) FOREIGN TRADE ZONES General Provisions § 146.2 Port director as...

  9. Interactive decision making using dissimilarity to visually represented prototypes

    NARCIS (Netherlands)

    Migut, M.A.; van Gemert, J.C.; Worring, M.; Miksch, S.; Ward, M.

    2011-01-01

    To make informed decisions, an expert has to reason with multi-dimensional, heterogeneous data and analysis results of these. Items in such datasets are typically represented by features. However, as argued in cognitive science, features do not yield an optimal space for human reasoning. In fact,

  10. Under-Representation in Nationally Representative Secondary Data

    Science.gov (United States)

    Frederick, Karen; Barnard-Brak, Lucy; Sulak, Tracey

    2012-01-01

    There has been a significant increase in the use of secondary data sets. Many such data sets purport to be nationally representative. Secondary data sets include research commissioned by the National Center for Education Statistics, the Centers for Disease Control, and other public entities. Research increasingly utilizes these secondary data in…

  11. Interactive decision making using dissimilarity to visually represented prototypes

    NARCIS (Netherlands)

    Migut, M.A.; van Gemert, J.C.; Worring, M.; Miksch, S.; Ward, M.

    2011-01-01

    To make informed decisions, an expert has to reason with multi-dimensional, heterogeneous data and analysis results of these. Items in such datasets are typically represented by features. However, as argued in cognitive science, features do not yield an optimal space for human reasoning. In fact, hu

  12. 5 CFR 919.915 - Agent or representative.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Agent or representative. 919.915 Section 919.915 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 919.915 Agent or...

  13. 78 FR 28124 - Registry for Attorneys and Representatives

    Science.gov (United States)

    2013-05-14

    ... before EOIR upon completing the registration process. While administrative suspension, on its own, is not... addresses electronically by completing a two-step process. First, registrants must log in to their eRegistry... additional instructions regarding the registration process. DATES: Attorneys and accredited representatives...

  14. Identifying and Representing Elements of Local Contexts in Namibia

    DEFF Research Database (Denmark)

    Rodil, Kasper; Løvborg Jensen, Kasper; Rehm, Matthias;

    2013-01-01

    In an attempt to represent local context in a 3D visualisa- tionfor rural elders in Namibia we have foundmajor dierences in thecon- ceptualizationof this context between external and local partners in the co-creation process. Through the evaluation of a mobile context capture tool we found a clea...

  15. Aggregation without the Aggravation? Nonparametric Analysis of the Representative Consumer

    NARCIS (Netherlands)

    Cherchye, L.J.H.; Crawford, I.; de Rock, B.; Vermeulen, F.M.P.

    2011-01-01

    Abstract: In the tradition of Afriat (1967), Diewert (1973) and Varian (1982), we provide a revealed preference characterisation of the representative consumer. Our results are simple and complement those of Gorman (1953, 1961), Samuelson (1956) and others. They can also be applied to data very read

  16. Using sound to represent spatial data in ArcGIS

    Science.gov (United States)

    Bearman, Nick; Fisher, Peter F.

    2012-09-01

    An extension to ESRI's, ArcGIS was created to allow spatial data to be represented using sound. A number of previous studies have used sound in combination with visual stimuli, but only a limited selection have looked at this with explicit reference to spatial data and none have created an extension for industry standard GIS software. The extension can sonify any raster data layer and represent this using piano notes. The user can choose from a number of different scales of piano notes and decide how the program plays the sound; this flexibility allows the extension to effectively represent a number of different types of data. The extension was evaluated in one-to-one semi-structured interviews with geographical information professionals, who explored aspects of a number of different data sets. Further research is needed to discover the best use of sound in a spatial data context, both in terms of which sounds to use and what data are most effectively represented using those sounds.

  17. Education and support for representative, direct and stealth democracy

    NARCIS (Netherlands)

    Coffé, Hilde; Michels, Ank

    2014-01-01

    Using data collected within the scope of a Dutch internet panel survey (LISS) in 2011, this study tracks public support for direct, stealth and representative democracy according to educational level. Our findings indicate that, in terms of overall support for each specific type of democracy, lower

  18. New Strategies for Representing Mental Illness on Canadian Stages

    Science.gov (United States)

    Johnston, Kirsty

    2009-01-01

    Workman Arts, a Toronto-based theatre and visual arts company with a 20-year history, provides a rich site for re-imagining stigmatised representations of mental illness. Writing and performing against a long tradition of representing people with mental illnesses as incoherent speakers and visually different, company members seek to re-imagine…

  19. 78 FR 19400 - Registry for Attorneys and Representatives

    Science.gov (United States)

    2013-04-01

    ... the alien's case, which might include granting one-time permission for the attorney or accredited... confusion as to who is representing a particular alien.\\6\\ Further, registered attorneys and accredited... connected computers and other devices, this final rule requires that attorneys and...

  20. 5 CFR 9701.516 - Allotments to representatives.

    Science.gov (United States)

    2010-01-01

    ... HUMAN RESOURCES MANAGEMENT SYSTEM Labor-Management Relations § 9701.516 Allotments to representatives... Section 9701.516 Administrative Personnel DEPARTMENT OF HOMELAND SECURITY HUMAN RESOURCES MANAGEMENT... Authority by a labor organization alleging that 10 percent of the employees in an appropriate unit in the...

  1. Crime’s face: Imagining and representing kleptomania

    NARCIS (Netherlands)

    Haan, de W.J.M.

    2015-01-01

    Marlene Dumas is regarded as one of the most important international painters of this time. In this article, an analysis is made of what her painting The Kleptomaniac (2005) and, in particular, what its title represents. Drawing upon art history, I begin by looking at the original Portrait of a Klep

  2. Reaching a Representative Sample of College Students: A Comparative Analysis

    Science.gov (United States)

    Giovenco, Daniel P.; Gundersen, Daniel A.; Delnevo, Cristine D.

    2016-01-01

    Objective: To explore the feasibility of a random-digit dial (RDD) cellular phone survey in order to reach a national and representative sample of college students. Methods: Demographic distributions from the 2011 National Young Adult Health Survey (NYAHS) were benchmarked against enrollment numbers from the Integrated Postsecondary Education…

  3. 22 CFR 903.4 - Participation of exclusive representative.

    Science.gov (United States)

    2010-04-01

    ... Section 903.4 Foreign Relations FOREIGN SERVICE GRIEVANCE BOARD INITIATION AND DOCUMENTATION OF CASES § 903.4 Participation of exclusive representative. (a) Upon the initiation of a case, the executive secretary shall ascertain from the Agency, the grievant/charged employee and any labor organization which...

  4. Representing adaptive eLearning strategies in IMS Learning Design

    NARCIS (Netherlands)

    Burgos, Daniel; Tattersall, Colin; Koper, Rob

    2006-01-01

    Burgos, D., Tattersall, C., & Koper, E. J. R. (2006). Representing adaptive eLearning strategies in IMS Learning Design. In R. Koper & K. Stefanov (Eds.), Proceedings of the International Workshop in Learning Networks for Lifelong Competence Development (pp. 54-60). March, 30-31, 2006, Sofia, Bulgar

  5. Evaluating Admission Criteria Effects for Under-Represented Groups

    Science.gov (United States)

    Childs, Ruth A.; Ferguson, Amanda K.; Herbert, Monique B.; Broad, Kathryn; Zhang, Jingshun

    2016-01-01

    The effects that admission criteria may have for under-represented groups are an important concern for programs seeking to improve access to post-secondary education. Using data from a large preservice teacher education program in the Canadian province of Ontario, we demonstrate two approaches to evaluating the effects of admission criteria. The…

  6. Do Netizen Representatives Deserve A Seat in the Legislature?

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The entry of a netizen representative to the local people’s congress of Luoyang City, central China’s Henan Province, is causing growing controversy as the questioning of their credentials surfaces. The issue has been widely debated during this year’s sessions of the National

  7. Representative sets and irrelevant vertices: New tools for kernelization

    CERN Document Server

    Kratsch, Stefan

    2011-01-01

    Recent work of the present authors provided a polynomial kernel for Odd Cycle Transversal by introducing matroid-based tools into kernelization. In the current work we further establish the usefulness of matroid theory to kernelization by showing applications of a result on representative sets due to Lov\\'asz (Combinatorial Surveys 1977) and Marx (TCS 2009). We give two types of applications: 1. Direct applications of the representative objects idea. In this direction, we give a polynomial kernel for Almost 2-SAT by reducing the problem to a cut problem with pairs of vertices as sinks, and subsequently reducing the set of pairs to a representative subset of bounded size. This implies polynomial kernels for several other problems, including Vertex Cover parameterized by the size of the LP gap, and the RHorn-Backdoor Deletion Set problem from practical SAT solving. We also get a polynomial kernel for Multiway Cut with deletable terminals, by producing a representative set of vertices, of bounded size, which is ...

  8. Education and support for representative, direct and stealth democracy

    NARCIS (Netherlands)

    Coffé, Hilde|info:eu-repo/dai/nl/304824186; Michels, Ank|info:eu-repo/dai/nl/11124501X

    2014-01-01

    Using data collected within the scope of a Dutch internet panel survey (LISS) in 2011, this study tracks public support for direct, stealth and representative democracy according to educational level. Our findings indicate that, in terms of overall support for each specific type of democracy, lower

  9. Do Normative Judgements Aim to Represent the World?

    NARCIS (Netherlands)

    Streumer, Bart

    2013-01-01

    Many philosophers think that normative judgements do not aim to represent the world. In this paper, I argue that this view is incompatible with the thought that when two people make conflicting normative judgements, at most one of these judgements is correct. I argue that this shows that normative j

  10. Representing and Inferring Visual Perceptual Skills in Dermatological Image Understanding

    Science.gov (United States)

    Li, Rui

    2013-01-01

    Experts have a remarkable capability of locating, perceptually organizing, identifying, and categorizing objects in images specific to their domains of expertise. Eliciting and representing their visual strategies and some aspects of domain knowledge will benefit a wide range of studies and applications. For example, image understanding may be…

  11. The role of a representative reinsurer in optimal reinsurance

    NARCIS (Netherlands)

    T.J. Boonen; K.S. Tan; S.C. Zhuang

    2016-01-01

    In this paper, we consider a one-period optimal reinsurance design model with nn reinsurers and an insurer. For very general preferences of the insurer and that all reinsurers use a distortion premium principle, we establish the existence of a representative reinsurer and this in turn facilitates so

  12. Crime’s face: Imagining and representing kleptomania

    NARCIS (Netherlands)

    Haan, de W.J.M.

    2015-01-01

    Marlene Dumas is regarded as one of the most important international painters of this time. In this article, an analysis is made of what her painting The Kleptomaniac (2005) and, in particular, what its title represents. Drawing upon art history, I begin by looking at the original Portrait of a

  13. Do Normative Judgements Aim to Represent the World?

    NARCIS (Netherlands)

    Streumer, Bart

    2013-01-01

    Many philosophers think that normative judgements do not aim to represent the world. In this paper, I argue that this view is incompatible with the thought that when two people make conflicting normative judgements, at most one of these judgements is correct. I argue that this shows that normative j

  14. 20 CFR 404.1705 - Who may be your representative.

    Science.gov (United States)

    2010-04-01

    ...) Attorney. You may appoint as your representative in dealings with us, any attorney in good standing who— (1) Has the right to practice law before a court of a State, Territory, District, or island possession of the United States, or before the Supreme Court or a lower Federal court of the United States; (2)...

  15. 20 CFR 416.1505 - Who may be your representative.

    Science.gov (United States)

    2010-04-01

    ...) Attorney. You may appoint as your representative in dealings with us any attorney in good standing who— (1) Has the right to practice law before a court of a State, Territory, District, or island possession of the United States, or before the Supreme Court or a lower Federal court of the United States; (2)...

  16. Voice of the People: Representative Government in the United States.

    Science.gov (United States)

    Bliss, Pam, Ed.; Heinz, Ann, Ed.; Kaplan, Howard, Ed.; Landman, James, Ed.

    2001-01-01

    This magazine aims to help high school teachers of civics, government, history, law, and law-related education program developers educate students about legal issues. This issue focuses on voting. It contains 11 articles: (1) "The Project of Democracy" (A. Keyssar) demonstrates how the story of the right to vote represents a slow and fitful…

  17. Anti-tumor effect of 5-aza-2'-deoxycytidine by inhibiting telomerase activity in hepatocellular carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Shuang-Fen Tao; Chang-Song Zhang; Xian-Ling Guo; Yun Xu; Shan-Shan Zhang; Jian-Rui Song; Rong Li

    2012-01-01

    AIM:To investigate the effect of the demethylating reagent 5-aza-2'-deoxycitidine (DAC) on telomerase activity in hepatocellular carcinoma (HCC) cell lines,SMMC-7721 and HepG2.METHODS:The related gene expression in cell lines was examined by real-time reverse transcription-polymerase chain reaction and Western blotting analysis.The telomerase activity was examined by telomeric repeat amplification protocol-enzyme-linked immunosorbent assay and DNA methylation was determined by methylation-specific polymerase chain reaction.RESULTS:The telomerase activity was significantly reduced in both cell lines treated with DAC,accompanied by downregulation of telomerase reverse transcriptase (hTERT).We also observed the effect of DAC on the methylation status of hTERT promoter and the expression of regulatory genes,such as c-myc,p15,p16,p21,E2F1,and WT1.The methylation status of hTERT promoter could be reversed in SMMC-7721 by DAC,but not in HepG2 cells.However,p16 expression could be reactivated by demethylation of its promoter,and c-Myc expression was repressed in both cell lines.Moreover,DAC could enhance the sensitivity to the chemotherapeutic agents,such as cisplatin,by induction of apoptosis of HCC cells.CONCLUSION:The DAC exerts its anti-tumor effects in HCC cells by inhibiting the telomerase activity.

  18. The mediation of Representative Council of Learners policy in ...

    African Journals Online (AJOL)

    Erna Kinsey

    human resource and political frames of Bolman and Deal (1997) as the basis of ... Act of 1996, which attempts to transform the governance and management .... activities, organizing various recreational activities like talent shows, helping.

  19. 地西他滨对急性白血病患者甲基化凋亡蛋白酶活化因子1基因的去甲基化作用%Demethylation stduy of decitabine in acute leukemia patients with Apaf-1 gene methylated

    Institute of Scientific and Technical Information of China (English)

    郭军; 杨恩芹; 杨晖

    2013-01-01

    Objective To investigate the effectiveness of decitabine demethylation in treatment of acute leukemia.Methods Methylation specific PCR (MSP) was used to detected the methylation status of Apaf-1 gene promoter.10 cases entering the group.MSP was used to detected the 10 cases methylation status of Apaf-1 promoter between pre-and post-treatment of dicitabine.RT-PCR method used was to detect the differential expression levels of Apaf-1 mRNA in acute leukemia bone marrow mononuclear cell between preand post-treatment of decitabine.Results In post-treatment of decitabine,6 cases Apaf-1 gene promoter was demethylated.The loss expression of Apaf-1 mRNA re-expressed in 4 cases.6 cases Apaf-1 mRNA still express deletion.6 cases patients have Apaf-1 mRNA exprssion deletion,However,4 cases Apaf-1 gene was demethylated,2 cases methylated in post-treatment,maybe related to allele deletion or allelic varriants.Conclusion Post treatment of decitabine.Apaf-1 gene promotor was demethylated and repress the expression of Apaf-1 mRNA,play a key role in apoptosis maybe a new method for treatment of acute leukemia.%目的 探讨地西他滨去甲基化作用治疗急性白血病患者的有效性.方法 通过甲基化特异性PCR选取10例凋亡蛋白酶活化因子1(Apaf-1)基因启动子发生甲基化的患者,经地西他滨治疗后,通过甲基化特异性PCR检测患者Apaf-1基因去甲基化状态.通过反转录PCR检测10例患者经地西他滨治疗前后骨髓单个核细胞Apaf-1基因mRNA表达情况.结果 甲基化特异性PCR检测示,10例患者经地西他滨治疗后,6例发生了去甲基化.治疗前10例患者因甲基化Apaf-1 mRNA均表达缺失,经地西他滨治疗后,4例重新表达,6例未表达.治疗后6例Apaf-1 mRNA表达缺失的患者中,4例Apaf-1基因未发生去甲基化,2例发生去甲基化,考虑可能与等位基因缺失或突变有关.结论 地西他滨通过使Apaf-1基因启动子去甲基化恢复抑癌基因的表达,发挥其凋亡中的关键因子作用.

  20. Representativeness and seasonality of major ion records derived from NEEM firn cores

    Directory of Open Access Journals (Sweden)

    G. Gfeller

    2014-10-01

    Full Text Available The seasonal and annual representativeness of ionic aerosol proxies (among others, calcium, sodium, ammonium and nitrate in various firn cores in the vicinity of the NEEM drill site in northwest Greenland have been assessed. Seasonal representativeness is very high as one core explains more than 60% of the variability within the area. The inter-annual representativeness, however, can be substantially lower (depending on the species making replicate coring indispensable to derive the atmospheric variability of aerosol species. A single core at the NEEM site records only 30% of the inter-annual atmospheric variability in some species, while five replicate cores are already needed to cover approximately 70% of the inter-annual atmospheric variability in all species. The spatial representativeness is very high within 60 cm, rapidly decorrelates within 10 m but does not diminish further within 3 km. We attribute this to wind reworking of the snow pack leading to sastrugi formation. Due to the high resolution and seasonal representativeness of the records we can derive accurate seasonalities of the measured species for modern (AD 1990–2010 times as well as for pre-industrial (AD 1623–1750 times. Sodium and calcium show similar seasonality (peaking in February and March respectively for modern and pre-industrial times, whereas ammonium and nitrate are influenced by anthropogenic activities. Nitrate and ammonium both peak in May during modern times, whereas during pre-industrial times ammonium peaked during July–August and nitrate during June–July.