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51.
Xing C Sestak AL Kelly JA Nguyen KL Bruner GR Harley JB Gray-McGuire C 《Human genetics》2007,120(5):623-631
Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by both population and phenotypic heterogeneity.
Our group previously identified linkage to SLE at 4p16 in European Americans (EA). In the present study we replicate this
linkage effect in a new cohort of 76 EA families multiplex for SLE by model-free linkage analysis. Using densely spaced microsatellite
markers in the linkage region, we have localized the potential SLE susceptibility gene(s) to be telomeric to the marker D4S2928
by haplotype construction. In addition, marker D4S394 showed marginal evidence of linkage disequilibrium with the putative
disease locus by the transmission disequilibrium test and significant evidence of association using a family-based association
approach as implemented in the program ASSOC. We also performed both two-point and multipoint model-based analyses to characterize
the genetic model of the potential SLE susceptibility gene(s), and the lod scores both maximized under a recessive model with
penetrances of 0.8. Finally, we performed a genome-wide scan of the total 153 EA pedigrees and evaluated the possibility of
interaction between linkage signals at 4p16 and other regions in the genome. Fourteen regions on 11 chromosomes (1q24, 1q42,
2p11, 2q32, 3p14.2, 4p16, 5p15, 7p21, 8p22, 10q22, 12p11, 12q24, 14q12, 19q13) showed evidence of linkage, among which, signals
at 2p11, 12q24 and 19q13 also showed evidence of interaction with that at 4p16. These results provide important additional
information about the SLE linkage effect at 4p16 and offer a unique approach to uncovering susceptibility loci involved in
complex human diseases. 相似文献
52.
M. Crispo A. P. Mulet L. Tesson N. Barrera F. Cuadro P. C. dos Santos-Neto T. H. Nguyen A. Crénéguy L. Brusselle I. Anegón A. Menchaca 《PloS one》2015,10(8)
While CRISPR/Cas9 technology has proven to be a valuable system to generate gene-targeted modified animals in several species, this tool has been scarcely reported in farm animals. Myostatin is encoded by MSTN gene involved in the inhibition of muscle differentiation and growth. We determined the efficiency of the CRISPR/Cas9 system to edit MSTN in sheep and generate knock-out (KO) animals with the aim to promote muscle development and body growth. We generated CRISPR/Cas9 mRNAs specific for ovine MSTN and microinjected them into the cytoplasm of ovine zygotes. When embryo development of CRISPR/Cas9 microinjected zygotes (n = 216) was compared with buffer injected embryos (n = 183) and non microinjected embryos (n = 173), cleavage rate was lower for both microinjected groups (P<0.05) and neither was affected by CRISPR/Cas9 content in the injected medium. Embryo development to blastocyst was not affected by microinjection and was similar among the experimental groups. From 20 embryos analyzed by Sanger sequencing, ten were mutant (heterozygous or mosaic; 50% efficiency). To obtain live MSTN KO lambs, 53 blastocysts produced after zygote CRISPR/Cas9 microinjection were transferred to 29 recipient females resulting in 65.5% (19/29) of pregnant ewes and 41.5% (22/53) of newborns. From 22 born lambs analyzed by T7EI and Sanger sequencing, ten showed indel mutations at MSTN gene. Eight showed mutations in both alleles and five of them were homozygous for indels generating out-of frame mutations that resulted in premature stop codons. Western blot analysis of homozygous KO founders confirmed the absence of myostatin, showing heavier body weight than wild type counterparts. In conclusion, our results demonstrate that CRISPR/Cas9 system was a very efficient tool to generate gene KO sheep. This technology is quick and easy to perform and less expensive than previous techniques, and can be applied to obtain genetically modified animal models of interest for biomedicine and livestock. 相似文献
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56.
Nguyen DN Stump CA Walsh ES Fernandes C Davide JP Ellis-Hutchings M Robinson RG Williams TM Lobell RB Huber HE Buser CA 《Bioorganic & medicinal chemistry letters》2002,12(9):1269-1273
Compound 1 has been shown to be a dual prenylation inhibitor with FPTase (IC50=2 nM) and GGPTase-I (IC50=95 nM). Analogues of 1, which replaced the cyanophenyl group with various biaryls, led to the discovery of highly potent dual FPTase/GGPTase-I inhibitors. 4-trifluoromethylphenyl, trifluoropentynyl, and trifluoropentyl were identified as good p-cyano replacements. 相似文献
57.
Leslie W. Tari Michael Trzoss Daniel C. Bensen Xiaoming Li Zhiyong Chen Thanh Lam Junhu Zhang Christopher J. Creighton Mark L. Cunningham Bryan Kwan Mark Stidham Karen J. Shaw Felice C. Lightstone Sergio E. Wong Toan B. Nguyen Jay Nix John Finn 《Bioorganic & medicinal chemistry letters》2013,23(5):1529-1536
The bacterial topoisomerases DNA gyrase (GyrB) and topoisomerase IV (ParE) are essential enzymes that control the topological state of DNA during replication. The high degree of conservation in the ATP-binding pockets of these enzymes make them appealing targets for broad-spectrum inhibitor development. A pyrrolopyrimidine scaffold was identified from a pharmacophore-based fragment screen with optimization potential. Structural characterization of inhibitor complexes conducted using selected GyrB/ParE orthologs aided in the identification of important steric, dynamic and compositional differences in the ATP-binding pockets of the targets, enabling the design of highly potent pyrrolopyrimidine inhibitors with broad enzymatic spectrum and dual targeting activity. 相似文献
58.
Thomas V. Magee Seungil Han Sandra P. McCurdy Thuy-Trinh Nguyen Karl Granskog Eric S. Marr Bruce A. Maguire Michael D. Huband Jinshan Michael Chen Timothy A. Subashi Veerabahu Shanmugasundaram 《Bioorganic & medicinal chemistry letters》2013,23(6):1727-1731
A novel series of 3-O-carbamoyl erythromycin A derived analogs, labeled carbamolides, with activity versus resistant bacterial isolates of staphylococci (including macrolide and oxazolidinone resistant strains) and streptococci are reported. An (R)-2-aryl substituent on a pyrrolidine carbamate appeared to be critical for achieving potency against resistant strains. Crystal structures showed a distinct aromatic interaction between the (R)-2-aryl (3-pyridyl for 4d) substituent on the pyrrolidine and G2484 (G2505, Escherichia coli) of the Deinococcus radiodurans 50S ribosome (3.2 Å resolution). 相似文献
59.
Nguyen Thuy Trang Nguyen Thi Thuy Dung Tran Nguyen-Minh-An Van Vo Giau 《Neurochemical research》2022,47(3):552-573
Neurochemical Research - Neurodegenerative disorders are distinguished by the gradual deterioration of the nervous system’s structure and function due to oxidative stress, mitochondrial... 相似文献
60.
Baoquan Bao Hung The Dang Ping Zhang Jongki Hong Chong-O. Lee Hee Young Cho Jee H. Jung 《Bioorganic & medicinal chemistry letters》2009,19(21):6205-6208
In the course of our search for bioactive metabolites from a colonial tunicate of the family Polyclinidae, six new (1–6) cyclic fatty acid derivatives were isolated. Their planar structures were established on the basis of NMR and MS spectroscopic analyses. The relative configuration was determined by NOESY experiment. Compounds 1–6 represent a fused bicyclic skeleton possibly derived from α,ω-dicarboxylic acids such as eicosanedioic acid or docosanedioic acid via a Diels–Alder type of cyclization. Compounds 1–4 and 6 showed mild cytotoxicity against a panel of five human solid tumor cell lines. 相似文献