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971.
ME Ali U Hashim M Kashif S Mustafa YB Che Man SB Abd Hamid 《Genetics and molecular research : GMR》2012,11(2):1762-1772
The pig (Sus scrofa) mitochondrial genome was targeted to design short (15-30 nucleotides) DNA markers that would be suitable for biosensor-based hybridization detection of target DNA. Short DNA markers are reported to survive harsh conditions in which longer ones are degraded into smaller fragments. The whole swine mitochondrial-genome was in silico digested with AluI restriction enzyme. Among 66 AluI fragments, five were selected as potential markers because of their convenient lengths, high degree of interspecies polymorphism and intraspecies conservatism. These were confirmed by NCBI blast analysis and ClustalW alignment analysis with 11 different meat-providing animal and fish species. Finally, we integrated a tetramethyl rhodamine-labeled 18-nucleotide AluI fragment into a 3-nm diameter citrate-tannate coated gold nanoparticle to develop a swine-specific hybrid nanobioprobe for the determination of pork adulteration in 2.5-h autoclaved pork-beef binary mixtures. This hybrid probe detected as low as 1% pork in deliberately contaminated autoclaved pork-beef binary mixtures and no cross-species detection was recorded, demonstrating the feasibility of this type of probe for biosensor-based detection of pork adulteration of halal and kosher foods. 相似文献
972.
One-step construction of Pt nanoparticles-chitosan composite film (PtNPs-CS) was firstly proposed as a novel immobilization matrix for the enzymes to fabricate glucose biosensor. This novel interface embedded in situ PtNPs in CS hydrogel was developed by one-step electrochemical deposition in solution containing CS and chloroplatinic acid (H(2)PtCl(6)). Several techniques, including scanning electron microscopy (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronoamperometry were employed to characterize the assembly process and performance of the biosensor. Under the optimized experimental conditions, the resulting biosensor exhibited excellent linear behavior in the concentration range from 1.2 μM to 4.0 mM for the quantitative analysis of glucose with a limit of detection of 0.4 μM at a signal-to-noise ratio of 3. The apparent Michaelis-Menten constant (K(M)(app)) was evaluated to be 2.4 mM, showing good affinity. The proposed biosensor offered good amperometric responses to glucose due to the nanostructured sensing film provided plenty of active sites for the immobilization of glucose oxidase (GOD). 相似文献
973.
Pseudoxanthomonas spadix BD-a59, able to metabolize all six BTEX (benzene, toluene, ethylbenzene, and o-, m-, and p-xylene) compounds, was isolated from gasoline-contaminated sediment. Here, we report the complete 3.45-Mb genome sequence and annotation of strain BD-a59. These advance the understanding of strain BD-a59's genomic properties and pollutant metabolic versatility. 相似文献
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976.
Damali N. Martin Brenda J. Boersma Ming Yi Mark Reimers Tiffany M. Howe Harry G. Yfantis Yien Che Tsai Erica H. Williams Dong H. Lee Robert M. Stephens Allan M. Weissman Stefan Ambs 《PloS one》2009,4(2)
Background
African-American breast cancer patients experience higher mortality rates than European-American patients despite having a lower incidence of the disease. We tested the hypothesis that intrinsic differences in the tumor biology may contribute to this cancer health disparity.Methods and Results
Using laser capture microdissection, we examined genome-wide mRNA expression specific to tumor epithelium and tumor stroma in 18 African-American and 17 European-American patients. Numerous genes were differentially expressed between these two patient groups and a two-gene signature in the tumor epithelium distinguished between them. To identify the biological processes in tumors that are different by race/ethnicity, Gene Ontology and disease association analyses were performed. Several biological processes were identified which may contribute to enhanced disease aggressiveness in African-American patients, including angiogenesis and chemotaxis. African-American tumors also contained a prominent interferon signature. The role of angiogenesis in the tumor biology of African-Americans was further investigated by examining the extent of vascularization and macrophage infiltration in an expanded set of 248 breast tumors. Immunohistochemistry revealed that microvessel density and macrophage infiltration is higher in tumors of African-Americans than in tumors of European-Americans. Lastly, using an in silico approach, we explored the potential of tailored treatment options for African-American patients based on their gene expression profile. This exploratory approach generated lists of therapeutics that may have specific antagonistic activity against tumors of African-American patients, e.g., sirolimus, resveratrol, and chlorpromazine in estrogen receptor-negative tumors.Conclusions
The gene expression profiles of breast tumors indicate that differences in tumor biology may exist between African-American and European-American patients beyond the knowledge of current markers. Notably, pathways related to tumor angiogenesis and chemotaxis could be functionally different in these two patient groups. 相似文献977.
Jia-tang Li Jing Che Robert W. Murphy Hui Zhao Er-mi Zhao Ding-qi Rao Ya-ping Zhang 《Molecular phylogenetics and evolution》2009,53(2):509-522
The phylogenetic relationships among 12 genera of treefrogs (Family, Rhacophoridae), were investigated based on a large sequence data set, including five nuclear (brain-derived neurotrophic factor, proopiomelanocortin, recombination activating gene 1, tyrosinase, rhodopsin) and three mitochondrial (partial 12S and 16S ribosomal RNA and the complete valine t-RNA) genes. Phylogenetic analysis of the nuclear gene sequences resolved three major clades. The first group included Philautus, Pseudophilautus, Kurixalus, Gracixalus, and Theloderma moloch; Pseudophilautus and Kurixalus were sister taxa. The second group consisted of Nyctixalus and Theloderma. The third group contained Feihyla, Polypedates, Rhacophorus, and Chiromantis vittatus; Polypedates and Feihyla were sister taxa. Analyses of the nuclear and mitochondrial genes supported the following results: (1) Genus Liuixalus formed the sister group of all other rhacophorines. (2) Philautus, Theloderma, and Chiromantis were not resolved as monophyletic genera. Four groups, including Philautus ocellatus and P. hainanus, P. longchuanensis and P. gryllus, P. banaensis, and P. quyeti nested well within the genera Liuixalus, Pseudophilautus, Kurixalus, and Gracixalus, respectively. (3) Theloderma moloch and Chiromantis vittatus did not cluster with other species of Theloderma and Chiromantis, respectively. Foam nesting evolved only once, as did laying eggs in a jelly-like matrix containing some bubbles. Terrestrial direct development evolved twice in the Rhacophoridae. 相似文献
978.
Rina Barouch-Bentov Jianwei Che Christian C. Lee Yating Yang Ann Herman Yong Jia Anastasia Velentza James Watson Luise Sternberg Sunjun Kim Niusha Ziaee Andrew Miller Carie Jackson Manabu Fujimoto Mike Young Serge Batalov Yi Liu Markus Warmuth Tim Wiltshire Michael P. Cooke Karsten Sauer 《Molecular cell》2009,33(1):43-52
979.
DNA-PKcs基因沉默抑制人乳腺上皮细胞对低剂量辐射损伤的修复 总被引:1,自引:1,他引:0
DNA-PKcs作为DNA依赖性蛋白激酶(DNA-PK)的催化亚基在DNA双链断裂(DSBs)的非同源末端重组(NHEJ)通路中起重要的作用。本实验以人乳腺上皮细胞株MCF10F为研究对象,通过siRNA技术抑制细胞内DNA-PKcs的表达,用50cGy137CS照射细胞,测定细胞生长曲线以确定细胞对低剂量辐射(LDR)的敏感性,同时检测DNA修复相关蛋白表达的变化,旨在探讨DNA依赖蛋白激酶(DNA-PKcs)基因沉默对人乳腺上皮细胞株MCF10F低剂量辐射敏感性的影响及机制。结果显示:转染特异性siRNA可使人乳腺上皮细胞(MCF10F)DNA-PKcs基因沉默,增殖受到明显的抑制;50cGyγ射线辐射可使乳腺细胞内DNA-PKcs、Ku80、ATM、P53等DNA修复相关蛋白表达增多,但DNA-PKcs基因沉默细胞(MCF10Fpk)中,这些蛋白表达显著低于对照组(MCF10Fmock)。以上结果提示,DNA-PKcs基因沉默可引起乳腺细胞对低剂量辐射敏感性增加,其原因可能与相关DNA修复蛋白表达减少有关。 相似文献
980.