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41.
Victoria V. Abzianidze Sofya A. Zakharenkova Natalia I. Moiseeva Petr P. Beltyukov Valeriy A. Polukeev Yaroslav A. Dubrovskii Victor A. Kuznetsov Yuri G. Trishin Jennifer E. Mejia Alvin A. Holder 《Bioorganic & medicinal chemistry letters》2019,29(1):59-61
New derivatives of phaeosphaeride A (PPA) were synthesized and characterized. Anti-tumor studies were carried out on the U937, HCT-116, PC3, MCF-7, A549, К562, NCI-H929, Jurkat, THP-1, RPMI8228 tumor cell lines, and on the HEF cell line. All the compounds synthesized were found to have better efficacy than PPA towards the tumor cell lines mentioned. Compound 6 (IC50?=?0.59?±?0.27?µM) was observed to be 11 times more active than PPA (IC50?=?6.5?±?0.30?µM) towards the NCI-H929 cell line, with a therapeutic index of 18. Compound 6 was determined to be over half and 16 times more active than etoposide towards the NCI-H929 (IC50?=?0.9?±?0.05?µM) and A549 (IC50?=?100?±?7.0?µM) cell lines, respectively. 相似文献
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Reconstruction of the eyelids can range from simple repair to the integration of multiple complex procedures. Knowledge of eyelid anatomy, adequate preoperative planning, and meticulous surgical technique will optimize the anatomical and functional result. The purpose of this article is to review the relevant anatomy for eyelid reconstruction, to simplify defect analysis and preoperative planning, and to provide options for reconstruction of this complex area. 相似文献
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Zheng HY Sugimoto C Hasegawa M Kobayashi N Kanayama A Rodas A Mejia M Nakamichi J Guo J Kitamura T Yogo Y 《Journal of molecular evolution》2003,56(1):18-27
Many genetic studies using human mtDNA or the Y chromosome have been conducted to elucidate the relationships among the three Native American groups speaking Amerind, Na-Dene, and Eskimo-Aleut. Human polyomavirus JC (JCV) may also help to gain insights into this issue. JCV isolates are classified into more than 10 geographically distinct genotypes (designated subtypes here), which were generated by splits in the three superclusters, Types A, B, and C. A particular subtype of JCV (named MY) belonging to Type B is spread in both Japanese/Koreans and Native Americans speaking Amerind or Na-Dene. In this study, we evaluated the phylogenetic relationships among MY isolates worldwide, using the whole-genome approach, with which a highly reliable phylogeny of JCV isolates can be reconstructed. Thirty-six complete sequences belonging to MY (10 from Japanese/Koreans, 24 from Native Americans, and 2 from others), together with 54 belonging to other subtypes around the world, were aligned and subjected to phylogenetic analysis using the neighbor-joining and maximum-likelihood methods. In the resultant phylogenetic trees, the MY sequences diverged into two Japanese/Korean and five Native American clades with high bootstrap probabilities. Two of the Native American clades contained isolates mainly from Na-Denes and the others contained isolates mainly from Amerinds. The Na-Dene clades were not clustered together, nor were the Amerind clades. In contrast, the two Japanese/Korean clades were clustered at a high bootstrap probability. We concluded that there is no distinction between Amerinds and Na-Denes in terms of indigenous JCVs, although they are linguistically distinguished from each other. 相似文献
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Norman M. Halden Karen Mathers John A. Babaluk Sergio R. Mejia 《Environmental Biology of Fishes》2004,71(1):53-61
Otoliths taken from fish from Eden Lake, Manitoba show yellow–green and red cathodoluminescence of varying intensity that corresponds to their annular structure. Proton-induced X-ray emission analysis shows manganese (Mn) concentrations of between 2 and 205ppm, zinc (Zn) concentrations between 2 and 290ppm and strontium (Sr) concentrations up to 1500ppm in the otoliths. The distribution of luminescence correlates with the distribution of Mn. The Mn, Zn and Sr are likely derived from the monzonitic rocks surrounding the lake. Variations in the distribution of cathodoluminescence may be a useful tool for evaluating changes in environmental chemistry and fish life histories. 相似文献
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Patel H Christensen KE Mejia N MacKenzie RE 《Archives of biochemistry and biophysics》2002,403(1):145-148
We have isolated the cDNA and the gene encoding the murine cytoplasmic methylenetetrahydrofolate dehydrogenase-methenyltetrahydrofolate cyclohydrolase-formyltetrahydrofolate synthetase (DCS). Comparison of these sequences with the 3'-untranslated region of the mitochondrial NAD(+)-dependent methylenetetrahydrofolate dehydrogenase-cyclohydrolase (mt-DC) revealed areas of significant homology. Both exon and intron sequences of the synthetase domain of DCS are homologous to sequences in the untranslated region of mt-DC. A similar comparison between the mt-DC and the DCS sequences of humans as well as Drosophila supports the conclusion that in higher eukaryotes the bifunctional mt-DC replaced a trifunctional precursor through inactivation of the synthetase domain. The mt-DC should be considered in models of one-carbon folate fluxes in mammals. 相似文献
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Patel H Di Pietro E Mejia N MacKenzie RE 《Archives of biochemistry and biophysics》2005,442(1):133-139
Mouse fibroblasts in which the mthfd2 gene encoding mitochondrial NAD-dependent methylenetetrahydrofolate dehydrogenase-cyclohydrolase (NMDMC) was previously inactivated were infected with retroviral expression constructs of dehydrogenase/cyclohydrolase cDNA. Cellular fractionation confirmed that the expressed proteins were properly targeted to the mitochondria. Expression of the NAD-dependent methylenetetrahydrofolate dehydrogenase-cyclohydrolase enzyme in mitochondria corrected the glycine auxotrophy of the null mutant cells. A construct in which the cyclohydrolase activity of NMDMC was inactivated by point mutation also rescued the glycine auxotrophy, although poorly. This suggests that the cyclohydrolase activity is also required to ensure optimal production of 10-formyltetrahydrofolate. The expression of the NADP-dependent methylenetetrahydrofolate dehydrogenase-cyclohydrolase-synthetase in the mitochondria also reversed the glycine requirement of the null cells demonstrating that the use of the NAD cofactor is not absolutely essential to maintain the flux of one-carbon metabolites. All rescued cells demonstrated a decrease in the ratio of incorporation of exogenous formate to serine in standardized radiolabeling studies. This ratio, which is approximately 2.5 for nmdmc(-/-) cells and 0.3 for the wild type cells under the conditions used, is a qualitative indicator of the ability of the mitochondria of the cells to generate formate. 相似文献
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Dora Buonfrate Marco Sequi Rojelio Mejia Ruben O. Cimino Alejandro J. Krolewiecki Marco Albonico Monica Degani Stefano Tais Andrea Angheben Ana Requena-Mendez José Mu?oz Thomas B. Nutman Zeno Bisoffi 《PLoS neglected tropical diseases》2015,9(2)