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991.
Xinping Liu Sung Ho Moon David J. Mancuso Christopher M. Jenkins Shaoping Guan Harold F. Sims Richard W. Gross 《Analytical biochemistry》2013
A highly sensitive, specific, and robust method for the analysis of oxidized metabolites of linoleic acid (LA), arachidonic acid (AA), and docosahexaenoic acid (DHA) was developed using charge-switch derivatization, liquid chromatography–electrospray ionization tandem mass spectrometry (LC–ESI MS/MS) with selected reaction monitoring (SRM) and quantitation by high mass accuracy analysis of product ions, thereby minimizing interferences from contaminating ions. Charge-switch derivatization of LA, AA, and DHA metabolites with N-(4-aminomethylphenyl)-pyridinium resulted in a 10- to 30-fold increase in ionization efficiency. Improved quantitation was accompanied by decreased false positive interferences through accurate mass measurements of diagnostic product ions during SRM transitions by ratiometric comparisons with stable isotope internal standards. The limits of quantitation were between 0.05 and 6.0 pg, with a dynamic range of 3 to 4 orders of magnitude (correlation coefficient r2 > 0.99). This approach was used to quantitate the levels of representative fatty acid metabolites from wild-type (WT) and iPLA2γ–/– mouse liver identifying the role of iPLA2γ in hepatic lipid second messenger production. Collectively, these results demonstrate the utility of high mass accuracy product ion analysis in conjunction with charge-switch derivatization for the highly specific quantitation of diminutive amounts of LA, AA, and DHA metabolites in biologic systems. 相似文献
992.
Yun Kyoung Kim Sanghoon Moon Mi Yeong Hwang Dong-Joon Kim Ji Hee Oh Young Jin Kim Bok-Ghee Han Jong-Young Lee Bong-Jo Kim 《Genomics》2013,101(2):134-138
Height is a classic polygenic trait with high heritability (h2 = 0.8). Recent genome-wide association studies have revealed many independent loci associated with human height. In addition, although many studies have reported an association between copy number variation (CNV) and complex diseases, few have explored the relationship between CNV and height. Recent studies reported that single nucleotide polymorphisms (SNPs) are highly correlated with common CNVs, suggesting that it is warranted to survey CNVs to identify additional genetic factors affecting heritable traits such as height.This study tested the hypothesis that there would be CNV regions (CNVRs) associated with height nearby genes from the GWASs known to affect height. We identified regions containing > 1% copy number deletion frequency from 3667 population-based cohort samples using the Illumina HumanOmni1-Quad BeadChip. Among the identified CNVRs, we selected 15 candidate regions that were located within 1 Mb of 283 previously reported genes. To assess the effect of these CNVRs on height, statistical analyses were conducted with samples from a case group of 370 taller (upper 10%) individuals and a control group of 1828 individuals (lower 50%).We found that a newly identified 17.7 kb deletion at chromosomal position 12q24.33, approximately 171.6 kb downstream of GPR133, significantly correlated with height; this finding was validated using quantitative PCR. These results suggest that CNVs are potentially important in determining height and may contribute to height variation in human populations. 相似文献
993.
Na Rae Kim Sang Moon Lee Min Wook Kim Hyeon Ji Yoon Won G. Hong Hae Jin Kim Hyoung Jin Choi Hyoung‐Joon Jin Young Soo Yun 《Liver Transplantation》2017,7(19)
In this study, hierarchically nanoporous pyropolymers (HN‐PPs) including numerous redox‐active heteroatoms are fabricated from polyaniline nanotubes by heating with KOH. In the large operating voltage range 1.0–4.8 V versus Li+/Li, HN‐PPs store amphicharges by a pseudocapacitive manner of Li‐ion (mainly <3.0 V) and electrochemical double layer formation of anion (primarily >3.0 V). Through these surface‐driven charge storage behaviors, HN‐PPs achieve a significantly high specific capacity of ≈460 mA h g?1 at 0.5 A g?1, maintaining specific capacities of 140 mA h g?1 at a high specific current of 30 A g?1 and 305 mA h g?1 after 2000 cycles at 3 A g?1. Furthermore, asymmetric energy storage devices based on HN‐PPs deliver a high specific energy of 265 W h kg?1 and high specific power of 5081 W kg?1 with long‐term cycling performance. 相似文献
994.
Leonid N. Ten Yeon-Hee Lee Jae-Jin Lee Su-Jin Park Seung-Yeol Lee Sangkyu Park Dae Sung Lee In-Kyu Kang Hee-Young Jung 《Journal of microbiology (Seoul, Korea)》2017,55(4):253-259
A Gram-stain-negative, non-motile, non-spore-forming, rod-shaped, aerobic bacterial strain, designated 16F3Y-2T, was isolated from the Han River, South Korea, and was characterized taxonomically using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that strain 16F3Y-2T belonged to the family Cytophagaceae in the phylum Bacteroidetes and was most closely related to ‘Hymenobacter terrae’ DG7A (98.01%), H. soli PB17T (97.26%), H. glaciei VUG-A130T (96.78%), H. antarcticus VUG-A42aaT (96.72%), H. ruber PB156T (96.61%), and H. saemangeumensis GSR0100T (95.77%). The G+C content of the genomic DNA of strain 16F3Y-2T was 62.9 mol%. The isolate contained MK-7 as the predominant respiratory quinone, and summed feature 3 (C16:1 ω7c/C16:1 ω6c; 35.5%), C15:0 iso (16.9%), C16:1 ω5c (10.9%), and C15:0 anteiso (9.9%) as major fatty acids. The major polar lipid was phosphatidylethanolamine. Phenotypic and chemotaxonomic data supported the affiliation of strain 16F3Y-2T with the genus Hymenobacter. However, strain 16F3Y-2T exhibited relatively low levels of DNA-DNA relatedness with ‘H. terrae’ KCTC 32554 (44.1%) and H. soli KCTC 12607T (24.3%), clearly indicating that the isolate constitutes a new genospecies. Strain 16F3Y-2T could be differentiated from its phylogenetic neighbors on the basis of several phenotypic, genotypic, and chemotaxonomic features. Therefore, strain 16F3Y-2T represents a novel species in the genus Hymenobacter, for which the name Hymenobacter daeguensis sp. nov. is proposed. The type strain is 16F3Y-2T (=KCTC 52537T =JCM 31654T). 相似文献
995.
ABSTRACT Lysozyme plays a central role in initiating and maintaining the antibacterial defense response of insect. A new family member of insect lysozyme, an antibacterial peptide, has been isolated from the hemolymph of the fifth instar larvae of Agrius convolvuli . Vaccination was proceeded with E. coli K12 D21 (4x106 cells of log phase) injection into the abdomen of the larvae. Agrius lysozyme was isolated by cation-exchange chromatography and RP-FPLC, and sequenced by HPLC system. It was observed that the purified Agrius lysozyme was heat-stable and had a molecular weight of approximately 15 kDa by SDS-PAGE. The N-terminal amino acid sequence of Agrius lysozyme is K-H-F-S-R-C-G-L-V-Q-E-L-F-W-Q-G-F-P with the highest similarity to that of Heliothis virescence , and it has been identified that the Agrius lysozyme belongs to c type lysozyme. 相似文献
996.
Jeong LS Park JG Choi WJ Moon HR Lee KM Kim HO Kim HD Chun MW Park HY Kim K Sheen YY 《Nucleosides, nucleotides & nucleic acids》2003,22(5-8):919-921
Novel halovinyl analogues of neplanocin A without 4'-hydroxymethyl group were easily synthesized starting from D-ribose via cyclopentenone 5 as a key intermediate and their inhibitory activity against SAH hydrolase was assayed. 相似文献
997.
Gun Yoen Na Kuk Hyeong Lee Moon Kyu Kim Seok Jong Lee Do Won Kim Jung Chul Kim 《Pigment cell & melanoma research》2003,16(4):383-387
We have examined the frequency of SNP polymorphisms within the melanocortin‐1 receptor (MC1R) and agouti signaling protein (ASIP) genes in 114 Korean vitiligo patients and 111 normal controls to assess the association of these loci with vitiligo risk. Using direct sequencing techniques, we found the following five MC1R coding region SNPs: Arg67Gln (G200A), Val92Met (G274A), Ile120Thr (T359C), Arg160Arg (C478A), and Gln163Arg (A488G). Of these, the most common were Val92Met at 14% in patients vs. 9% in controls (P = 0.17) and Gln163Arg at 17% in patients vs. 17% in controls (P = 0.84). Presence of the A allele of Val92Met (G274A) was higher in vitiligo patients {P = 0.12, odds ratio (OR) [95% confidence interval (CI)] = 1.68 (0.86–3.25)}. The other three variants showed a frequency <5% of both patients and controls. The ASIP 3′UTR genotype (g.8818A‐G) was also assessed in the same subjects. The frequency of the G allele of 3′UTR in ASIP was 17% in vitiligo and 12% in controls [P = 0.14, OR (95% CI) = 1.49 (0.87–2.54)]. Carriage of the G allele was higher in vitiligo patients [P = 0.17, OR (95% CI) = 1.50 (0.83–2.72)], and those who also carried MC1R Val92Met were more prone to vitiligo [eight of 111 patients vs. four of 111 in controls, P = 0.14, OR (95% CI) = 2.75 (0.71–8.69)]. None of these associations, however, reached statistical significance. 相似文献
998.
A novel inhibitor against maltose-producing alpha-amylase was prepared via stepwise degradation of a high-molecular-weight acarbose (HMWA) using Thermus maltogenic amylase (ThMA). The structure of the purified inhibitor was determined to be alpha-D-glucopyranosyl-alpha-acarviosinyl-D-glucopyranose (GlcAcvGlc) by (13)C NMR and MALDI-TOF/MS. Progress curves of PNPG2 hydrolysis by various amylolytic enzymes, including MGase, ThMA, and CDase I-5, in the presence of acarbose or GlcAcvGlc indicated a slow-binding mode of inhibition. Analytical ultracentrifugation and X-ray crystallography analyses revealed that the presence of GlcAcvGlc increased the dimerization of ThMA. The formation of dimer complexed with GlcAcvGlc might induce a conformational change in ThMA, leading to a two-step inhibition process. The inhibition potency of GlcAcvGlc for MGase, ThMA, and CDase I-5 was 3 orders of magnitude higher than that of acarbose. 相似文献
999.
In order to establish some cultural practices that can improve growth and survival of somatic embryo (SE)-derived microplants during the acclimatization period, Kalopanax septemlobus was uninoculated or inoculated with mycorrhizal fungi coded as AMM6 (a mixture of unidentified species of Glomus and Acaulospora collected in a closed mine tailing site in Bonghwa, Korea) during ex vitro and grown in oven-sterilized peat vermiculite medium. After 2 months, treated microplants were transferred into pots filled with the same medium amended with phosphorus fertilizer {0, 2, 4, 8, 16 and 32 mg P [as Ca(H2PO4)2·H2O] kg medium?1 coded as P0, P2, P4, P8, P16 and P32, respectively}. At this stage, inoculated plants were greener, with broader leaves and well-developed root systems and had higher survival than the uninoculated ones. After 6 months, inoculated plants were 54 % heavier than the uninoculated counterpart. In sterile medium, total dry weight of uninoculated plants was promoted at P8 and highest at P16. Total dry weight at P16 by uninoculated plants was attained at P4 by the mycorrhiza-inoculated counterpart. In non-sterile medium, total dry weight of inoculated plants was increased at P8. By contrast, uninoculated plants did not respond to the applied P rates. In conclusion, more SE-derived microplants survived and grew better in sterile medium. Maximum benefits from AMM6 was attained with applied 4 and 8 mg P kg medium?1 (P4–P8) in sterile and non-sterile medium, respectively. 相似文献
1000.
Lee CM Chang JH Moon DO Choi YH Choi IW Park YM Kim GY 《Biochemical and biophysical research communications》2008,374(2):248-252
In this study, we attempt to determine whether lycopene regulates inflammatory mediators in the ovalbumin (OVA)-induced murine asthma model. To address this, mice were sensitized and challenged with OVA, and then treated with lycopene before the last OVA challenge. Administration of lycopene significantly alleviated the OVA-induced airway hyperresponsiveness to inhaled methacholine. Administration of lycopene also resulted in a significant inhibition of the infiltration of inflammatory immunocytes into the bronchoalveolar lavage, and attenuated the gelatinolytic activity of matrix metalloproteinase-9 and the expression of eosinophil peroxidase. Additionally, lycopene reduced the increased levels of GATA-3 mRNA level and IL-4 expression in OVA-challenged mice. However, it increased T-bet mRNA level and IFN-γ expression in lycopene-challenged mice. These findings provide new insight into the immunopharmacological role of lycopene in terms of its effects in a murine model of asthma. 相似文献