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Choo RE Murphy CM Jones HE Huestis MA 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,814(2):369-373
This paper details a validated liquid chromatography atmospheric pressure chemical ionization tandem mass spectrometry (LC-APCI-MS/MS) method for the quantification of methadone, and its metabolites 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), 2-ethyl-5-methyl-3,3-diphenylpyraline (EMDP) and methadol in human meconium. Limits of detection (LOD) were determined to be 1.0 ng/g for methadone, EDDP and EMDP and 2.5 ng/g for methadol. The limits of quantitation (LOQ) for methadone, EDDP, EMDP were 5 and 25 ng/g for methadol. Linearity ranged from 5.0 to 500 ng/g. Following solid-phase extraction, no matrix effect was observed. This method proved to be suitable for the quantification of methadone, EDDP and EMDP and the semi-quantitation of methadol in meconium. Literature review revealed no other published LC-APCI-MS/MS method for the detection of methadone and its three main metabolites in meconium specimens. 相似文献
85.
High-resolution identification of chromosomal abnormalities using oligonucleotide arrays containing 116,204 SNPs 下载免费PDF全文
Slater HR Bailey DK Ren H Cao M Bell K Nasioulas S Henke R Choo KH Kennedy GC 《American journal of human genetics》2005,77(5):709-726
Mutation of the human genome ranges from single base-pair changes to whole-chromosome aneuploidy. Karyotyping, fluorescence in situ hybridization, and comparative genome hybridization are currently used to detect chromosome abnormalities of clinical significance. These methods, although powerful, suffer from limitations in speed, ease of use, and resolution, and they do not detect copy-neutral chromosomal aberrations--for example, uniparental disomy (UPD). We have developed a high-throughput approach for assessment of DNA copy-number changes, through use of high-density synthetic oligonucleotide arrays containing 116,204 single-nucleotide polymorphisms, spaced at an average distance of 23.6 kb across the genome. Using this approach, we analyzed samples that failed conventional karyotypic analysis, and we detected amplifications and deletions across a wide range of sizes (1.3-145.9 Mb), identified chromosomes containing anonymous chromatin, and used genotype data to determine the molecular origin of two cases of UPD. Furthermore, our data provided independent confirmation for a case that had been misinterpreted by karyotype analysis. The high resolution of our approach provides more-precise breakpoint mapping, which allows subtle phenotypic heterogeneity to be distinguished at a molecular level. The accurate genotype information provided on these arrays enables the identification of copy-neutral loss-of-heterozygosity events, and the minimal requirement of DNA (250 ng per array) allows rapid analysis of samples without the need for cell culture. This technology overcomes many limitations currently encountered in routine clinical diagnostic laboratories tasked with accurate and rapid diagnosis of chromosomal abnormalities. 相似文献
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Burke LE Styn MA Steenkiste AR Music E Warziski M Choo J 《Obesity (Silver Spring, Md.)》2006,14(11):2007-2017
Objective: The PREFER study objectives were to examine potential differences in weight loss during a standard behavioral intervention between subjects assigned to one of two calorie‐ and fat‐restricted diets [standard behavior treatment (SBT) and lacto‐ovo‐vegetarian ([SBT+LOV)], with or without regard to their preferred dietary treatment. This article reports the differences in outcomes between diet groups after the first 6 months of the intervention. Research Methods and Procedures: The study used a four‐group design. Subjects (n = 182) were randomized to a treatment preference group and then to a dietary treatment group. For this report, preference groups were combined to permit comparisons by dietary treatment only (SBT, n = 98; SBT+LOV, n = 84). Additional analyses compared SBT+LOV subjects who were 100% adherent (did not consume any meat, fish, or poultry, n = 47) to those who were <100% adherent (n = 24). Results: Significant differences were seen in the baseline to 6‐month change scores between the two groups for carbohydrate consumption (p = 0.013), protein consumption (p < 0.001), polyunsaturated‐to‐saturated fat ratio (p = 0.009), and low‐density lipoprotein‐cholesterol (LDL‐C) level (p = 0.013). Among SBT+LOV subjects, those who were 100% adherent experienced greater reductions in weight (p < 0.001), total cholesterol (p = 0.026), LDL‐C (p = 0.034), and glucose (p = 0.002) and consumed less fat (p = 0.030) compared with those who were <100% adherent. Discussion: Differences between dietary treatment groups at 6 months were minimal, most likely because one‐third of the SBT+LOV group did not follow the vegetarian diet and because both groups had the same calorie and fat restrictions. SBT+LOV subjects who were 100% adherent were more successful at both weight loss and cholesterol reduction than those who were <100% adherent, suggesting that vegetarian diets are efficacious for weight and cholesterol control. 相似文献
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Hyunmin Song Sei-Ryang Oh Hyeong-Kyu Lee Gyoonhee Han Joo-Heon Kim Hyeun Wook Chang Kyung-Eun Doh Hee-Kyung Rhee Hea-Young Park Choo 《Bioorganic & medicinal chemistry》2010,18(21):7580-7585
5-Lipoxygenase (5-LOX) is important enzyme in the biosynthesis of leukotrienes, and is a potential target in the treatment of asthma and allergy. We designed and synthesized a series of benzoxazoles and benzothiazoles as 5-LOX inhibitors. Fourteen compounds prepared showed the inhibition of LTC4 formation with IC50 value of 0.12–23.88 μM. Also two compounds 2d and 2g showed improved airway hypersensitiveness. 相似文献
88.
Yoo Lim Kam Hee-Kyung Rhee Hwa-Jung Kim Seung Keun Back Heung Sik Na Hea-Young Park Choo 《Bioorganic & medicinal chemistry》2010,18(6):2327-2336
A series of novel non-peptide diamide compounds was synthesized and evaluated as antibradykinin agents by utilizing guinea-pig ileum smooth muscle. Among the final compounds, (Z)-4-(4-(bis(4-fluorophenyl)methyl)piperazin-1-yl)-4-oxo-N-(4-phenylbutan-2-yl)but-2-enamide showed most favorable bradykinin inhibitory activity and demonstrated analgesic efficacies in the rat models of inflammatory and neuropathic pain. 相似文献
89.
Embryonic stem cells (ESC) hold the promise of overcoming many diseases as potential sources of, for example, dopaminergic neural cells for Parkinson’s Disease to pancreatic islets to relieve diabetic patients of their daily insulin injections. While an embryo has the innate capacity to develop fully functional differentiated tissues; biologists are finding that it is much more complex to derive singular, pure populations of primary cells from the highly versatile ESC from this embryonic parent. Thus, a substantial investment in developing the technologies to expand and differentiate these cells is required in the next decade to move this promise into reality. In this review we document the current standard assays for characterising human ESC (hESC), the status of ‘defined’ feeder-free culture conditions for undifferentiated hESC growth, examine the quality controls that will be required to be established for monitoring their growth, review current methods for expansion and differentiation, and speculate on the possible routes of scaling up the differentiation of hESC to therapeutic quantities. 相似文献
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