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1.
Synthesis of methyl
-Ribose was converted into methyl
and this, on tin-mediated allylation, gave a mixture of the 2-O-allyl and 3-O-allyl derivatives which were separated by chromatography. The more polar isomer was characterised as the 3-O-allyl derivative after conversion via
(which was also synthesised from
) into the known
. Methyl
was converted into methyl
via methyl
. 相似文献
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2.
Jia-Xin Jiang Karen J. Aitken Chris Sotiropolous Tyler Kirwan Trupti Panchal Nicole Zhang Shuye Pu Shoshana Wodak Cornelia Tolg Darius J. B?gli 《PloS one》2013,8(8)
Extracellular matrix changes are often crucial inciting events for fibroproliferative disease. Epigenetic changes, specifically DNA methylation, are critical factors underlying differentiated phenotypes. We examined the dependency of matrix-induced fibroproliferation and SMC phenotype on DNA methyltransferases. The cooperativity of matrix with growth factors, cell density and hypoxia was also examined. Primary rat visceral SMC of early passage (0–2) were plated on native collagen or damaged/heat-denatured collagen. Hypoxia was induced with 3% O2 (balanced 5% CO2 and 95% N2) over 48 hours. Inhibitors were applied 2–3 hours after cells were plated on matrix, or immediately before hypoxia. Cells were fixed and stained for DNMT3A and smooth muscle actin (SMA) or smooth muscle myosin heavy chain. Illumina 450 K array of CpG sites was performed on bisulfite-converted DNA from smooth muscle cells on damaged matrix vs native collagen. Matrix exquisitely regulates DNMT3A localization and expression, and influences differentiation in SMCs exposed to denatured matrix +/− hypoxia. Analysis of DNA methylation signatures showed that Matrix caused significant DNA methylation alterations in a discrete number of CpG sites proximal to genes related to SMC differentiation. Matrix has a profound effect on the regulation of SMC phenotype, which is associated with altered expression, localization of DNMTs and discrete changes DNA methylation. 相似文献
3.
The discovery of nucleotide diversity captured as single feature polymorphism (SFP) by using the expression array is a high-throughput and effective method in detecting genome-wide polymorphism. The efficacy of such method was tested in rice, and the results presented in the paper indicate high sensitivity in predicting SFP. The sensitivity of polymorphism detection was further demonstrated by the fact that no biasness was observed in detecting SFP with either single or multiple nucleotide polymorphisms. The high density SFP data that can be generated quite effectively by the current method has promise for high resolution genetic mapping studies, as physical location of features are well-defined on rice genome. 相似文献
4.
Archisman Ray Subodha Kumar Karna Trupti Rani Mohanty Himanshu Sekhar Swain Basanta Kumar Das 《Zeitschrift fur angewandte Ichthyologie》2019,35(4):1050-1052
Length–weight relationships (LWRs) were determined for seven riverine fish species from the river Ganga, India. Specimens were collected on a bi‐monthly basis from April 2017 to December 2018 using gill nets (mesh size 22–34 mm), cast nets (mesh size 16 mm) and bag nets (mesh size 14–22 mm). Total length was measured to the nearest 0.1 cm using a digital caliper and weight was recorded to the nearest 0.01 g on an electronic balance. From estimated length–weight relationships, the values for parameter “a” ranged from 0.004 (Bregmaceros mcclellandi and Setipinna tenuifilis) to 0.014 (Brachirus pan). Likewise, the values for the parameter “b” of the equation ranged from 2.958 (Bagarius bagarius) to 3.124 (Bregmaceros mcclellandi) and r2 from 0.978 (Gonialosa manmina) to 0.996 (Brachirus pan). 相似文献
5.
Bhasin D Cisek K Pandharkar T Regan N Li C Pandit B Lin J Li PK 《Bioorganic & medicinal chemistry letters》2008,18(1):391-395
A series of small molecule STAT3 inhibitors originally derived from our lead compound STA 21 were synthesized and evaluated. The most potent compound in this series, compound 1, exhibited the same anti-proliferative activities as STA 21 against prostate cancer cell lines that express constitutively active STAT3. Molecular docking showed compound 1 bound to the STAT3beta SH2 domain in a similar manner as STA 21. 相似文献
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7.
Dengue virus, a member of the family Flaviviridae, poses a serious public health threat worldwide. Dengue virus is a positive-sense RNA virus that harbors a genome of approximately 10.7 kb. Replication of dengue virus is mediated coordinately by cis-acting genomic sequences, viral proteins, and host cell factors. We have isolated and identified several host cell factors from baby hamster kidney cell extracts that bind with high specificity and high affinity to sequences within the untranslated regions of the dengue virus genome. Among the factors identified, Y box-binding protein-1 (YB-1) and the heterogeneous nuclear ribonucleoproteins (hnRNPs), hnRNP A1, hnRNP A2/B1, and hnRNP Q, bind to the dengue virus 3'-untranslated region. Further analysis indicated that YB-1 binds to the dengue virus 3' stem loop, a conserved structural feature located at the 3' terminus of the 3'-untranslated region of many flaviviruses. Analysis of the impact of YB-1 on replication of dengue virus in YB-1+/+ and YB-1-/- mouse embryo fibroblasts indicated that host YB-1 mediates an antiviral effect. Further studies demonstrated that this antiviral impact is due, at least in part, to a repressive role of YB-1 on dengue virus translation via a mechanism that requires viral genomic sequences. These results suggest a novel role for YB-1 as an antiviral host cell factor. 相似文献
8.
Bhatt T Jain V Jayathirtha MG Banerjee G Mishra SH 《Indian journal of experimental biology》2002,40(12):1382-1386
Adventitious roots, generated using leaf explants of P. nodiflora, and meristem explants of L. reticulata, were cultured on Murashige and Skoog (MS) medium supplemented with napthylacetic acid (2 microM) and indole butyric acid (3 microM) respectively. After 30 days, subculturing of roots in liquid MS medium with napthylacetic acid (1.5 microM) for P. nodiflora and indole butyric acid (3 microM) for L. reticulata afforded considerable increase in root mass. HPTLC profiles and microscopic examination of transverse sections of in vitro and naturally grown roots provided information on secondary metabolite accumulation vis-à-vis developmental stages of the root. 相似文献
9.
Poornima Parameswaran Ella Sklan Courtney Wilkins Trever Burgon Melanie A. Samuel Rui Lu K. Mark Ansel Vigo Heissmeyer Shirit Einav William Jackson Tammy Doukas Suman Paranjape Charlotta Polacek Flavia Barreto dos Santos Roxana Jalili Farbod Babrzadeh Baback Gharizadeh Dirk Grimm Mark Kay Satoshi Koike Peter Sarnow Mostafa Ronaghi Shou-Wei Ding Eva Harris Marie Chow Michael S. Diamond Karla Kirkegaard Jeffrey S. Glenn Andrew Z. Fire 《PLoS pathogens》2010,6(2)
We have used multiplexed high-throughput sequencing to characterize changes in small RNA populations that occur during viral infection in animal cells. Small RNA-based mechanisms such as RNA interference (RNAi) have been shown in plant and invertebrate systems to play a key role in host responses to viral infection. Although homologs of the key RNAi effector pathways are present in mammalian cells, and can launch an RNAi-mediated degradation of experimentally targeted mRNAs, any role for such responses in mammalian host-virus interactions remains to be characterized. Six different viruses were examined in 41 experimentally susceptible and resistant host systems. We identified virus-derived small RNAs (vsRNAs) from all six viruses, with total abundance varying from “vanishingly rare” (less than 0.1% of cellular small RNA) to highly abundant (comparable to abundant micro-RNAs “miRNAs”). In addition to the appearance of vsRNAs during infection, we saw a number of specific changes in host miRNA profiles. For several infection models investigated in more detail, the RNAi and Interferon pathways modulated the abundance of vsRNAs. We also found evidence for populations of vsRNAs that exist as duplexed siRNAs with zero to three nucleotide 3′ overhangs. Using populations of cells carrying a Hepatitis C replicon, we observed strand-selective loading of siRNAs onto Argonaute complexes. These experiments define vsRNAs as one possible component of the interplay between animal viruses and their hosts. 相似文献
10.