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921.
922.
Yong Zhang Seo Yoon Jung Changbae Jin Nam Doo Kim Ping Gong Yong Sup Lee 《Bioorganic & medicinal chemistry letters》2009,19(2):502-507
The involvement of μ-calpain in neurological disorders, such as stroke and Alzheimer’s disease has attracted considerable interest in the use of calpain inhibitors as therapeutic agents. 4-Aryl-4-oxobutanoic acid amide derivatives 4 were designed as acyclic variants of μ-calpain inhibitory chromone and quinolinone derivatives. Of the compounds synthesized, 4c-2, which possesses a 2-methoxymethoxy group at the phenyl ring and a primary amide at the warhead region most potently inhibited μ-calpain (IC50 = 0.34 μM). Our findings suggest that the 4-aryl-4-oxobutanoic acid amide derivatives should be considered as a new family of μ-calpain inhibitors. 相似文献
923.
Chung-Kyu Ryu Jung Yoon Lee Seong Hee Jeong Ji-Hee Nho 《Bioorganic & medicinal chemistry letters》2009,19(1):146-148
1H-Pyrrolo[3,2-g]quinoline-4,9-diones and 4,9-dioxo-4,9-dihydro-1H-benzo[f]indoles were synthesized and tested for in vitro antifungal activity against fungi. Among them tested, many compounds showed good antifungal activity. The results suggest that 1H-pyrrolo[3,2-g]quinoline-4,9-diones and 4,9-dioxo-4,9-dihydro-1H-benzo[f]indoles would be potent antifungal agents. 相似文献
924.
925.
Hyung Keun Oh Hyung Joo Yoon Min Jee Kim Hyung Uk Jeong Seong Ryul Kim Jae Sam Hwang Chang Hwan Bae Iksoo Kim 《Genes & genomics.》2009,31(4):293-303
The bumblebee species,Bombus, is an invaluable natural resource for greenhouse pollination. Low levels of genetic variation ofBombus ardens have been reported in a previous mitochondrial (mt) gene study. In this study, we sequenced the complete internal transcribed spacer 2 (ITS2) of the nuclear rDNA obtained from 100B. ardens individuals collected from several Korean localities, in an effort to assess its usefulness in characterizing the genetic diversity and relationships among populations of B. ardens. The ITS2 sequences ofB. ardens were shown to be longest among known insects, ranging in size from 1,971–1,984 bp. The sequences harbor four duplicated repeats-≈27 bp repeats, ≈20 bp repeats, ≈33 bp repeats, and ≈34 bp repeats-which have never before been reported in other insect ITS2 rDNA. The maximum sequence divergence of 1.01% among 96 sequence types confirmed the applicability of this molecule to the study of intraspecific variation, revealing higher sequence variation as compared to the previously studied mt COI gene. Overall, a very high per generation migration ratio (Nm = 5.83 ≈ infinite) and a very low level of genetic fixation (FST =0 –0.08) were noted to exist among populations ofB. ardens. The high estimation of gene flow among most populations-in particular, between the remote island Ulleungdo and several inland populations-suggest that historical events may be more responsible for the contemporary population structure of B. ardens. The finding of the lowest genetic diversity (π) in the population on Ulleungdo Island (π = 0.007434) may be reflective of a relatively small population size and the geographical isolation of the population as compared with other inland populations. 相似文献
926.
Soo-Young Choi Se-Kyung Oh Ho-Sung Yoon Sang-Heun Lee Un-Kyung Kim 《Genes & genomics.》2009,31(6):451-456
Microsatellites, short tandem repeats, are useful markers for genetic analysis because of their high frequency of occurrence over the genome, high information content due to variable repeat lengths, and ease of typing. To establish a panel of microsatellite markers useful for genetic studies for hereditary hearing loss in the Korean population, the allele frequencies and heterozygosities of 32 microsatellite markers in 172 unrelated Korean individuals were examined. The heterozygosity values for these markers ranged from 48 to 87%. All the markers except D6S1038 and D14S1034 marker showed PIC values over 0.5. This indicates these markers have a high degree of polymorphism and are randomly distributed in the Korean population. Therefore, the combinations of these STR loci provide a powerful tool to find the candidate loci of a causative gens for non-syndromic hearing loss in the Korean population. 相似文献
927.
928.
Byung Seok Moon Kathryn E. Carlson John A. Katzenellenbogen Tae Hyun Choi Dae Yoon Chi Jung Young Kim Gi Jeong Cheon Hun Yeong Koh Kyo Chul Lee Gwangil An 《Bioorganic & medicinal chemistry》2009,17(9):3479-3488
We have investigated halogen-substituted non-steroidal estrogens with selective binding affinity for the estrogen receptor β (ERβ that might be used for imaging the levels of this ER-subtype in breast tumors by positron emission tomography (PET). Based on diarylpropionitrile (DPN, 1a), a compound previously reported that has a 72-fold binding selectivity for ERβ, we developed a series of DPN analogs having methyl-, hydroxyl-, and halogen substituents, including fluoroethyl and fluoropropyl groups. In competitive radiometric binding assays with [3H]estradiol, all of these DPN analogs showed high ERβ/ERα selectivity; while the selectivity varied, in some cases it reached nearly 300-fold (RBA: ERα, 0.023%; ERβ, 6.25%). The absolute ERβ binding affinities, however, were not sufficient to merit further consideration for developing these ligands as PET imaging agents. 相似文献
929.
Se Ryun Kwon Yue Jai Kang Dong Jin Lee Eun Hye Lee Yoon Kwon Nam Sung Koo Kim Ki Hong Kim 《Molecular biotechnology》2009,42(2):154-159
Vibrio anguillarum ghosts (VAG) were generated, for the first time, using a conjugation vector containing a ghost bacteria inducing cassette,
pRK-λPR-cI-Elysis, in which the expression of PhiX174 lysis gene E was controlled by the P
R
/cI regulatory system of lambda phage. By scanning electron microscopy, holes ranging 80–200 nm in diameter were observed in
the VAG. To avoid the presence of bacterial genomic DNA and an antibiotic resistance gene in the final VAG product, we constructed
a new dual vector, pRK-λPR-cI-E-SNA, containing the E-mediated lysis cassette and the staphylococcal nuclease A (SNA)-mediated DNA degradation cassette, and generated safety-enhanced VAG for use as a fish vaccine. 相似文献
930.
Synthetic lethal mutants have been previously isolated in fission yeast Schizosaccharomyces pombe, which genetically interact with spmex67, in order to identify the genes involved in mRNA export. The nup211 gene was isolated by complementation of the growth defect in one of the synthetic lethal mutants, SLMex2, under synthetic
lethal condition. We showed that Nup211, fission yeast homolog of Mlpl/Mlp2/Tpr, is essential for vegetative growth and Nup211-GFP
proteins expressed at endogenous level are localized mainly in nuclear periphery. The accumulation of poly(A)+ RNA in the nucleus is exhibited when expression of nup211 is repressed or over-expressed. These results suggest that the Nup211 protein plays a pivotal role of mRNA export in fission
yeast. 相似文献