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排序方式: 共有809条查询结果,搜索用时 10 毫秒
31.
32.
Marjan Shafaati Natalia Mast Olof Beck Rima Nayef Gun Young Heo Linda Bj?rkhem-Bergman Dieter Lütjohann Ingemar Bj?rkhem Irina A. Pikuleva 《Journal of lipid research》2010,51(2):318-323
Cholesterol 24S-hydroxylase (CYP46A1) is of key importance for cholesterol homeostasis in the brain. This enzyme seems to be resistant toward most regulatory factors and at present no drug effects on its activity have been described. The crystal structures of the substrate-free and substrate-bound CYP46A1 were recently determined (Mast et al., Crystal structures of substrate-bound and substrate-free cytochrome P450 46A1, the principal cholesterol hydroxylase in the brain. Proc. Natl. Acad. Sci. USA. 2008. 105: 9546–9551). These structural studies suggested that ligands other than sterols can bind to CYP46A1. We show here that the antifungal drug voriconazole binds to the enzyme in vitro and inhibits CYP46A1-mediated cholesterol 24-hydroxylation with a Ki of 11 nM. Mice treated with daily intraperitoneal injections of voriconazole for 5 days had high levels of voriconazole in the brain and significantly reduced brain levels of 24S-hydroxycholesterol. The levels of squalene, lathosterol, and HMG-CoA reductase mRNA were reduced in the brain of the voriconazole-treated animals as well, indicating a reduced cholesterol synthesis. Most of this effect may be due to a reduced utilization of cholesterol by CYP46A1. One of the side-effects of voriconazole is visual disturbances. Because CYP46A1 is also expressed in the neural retina, we discuss the possibility that the inhibition of CYP46A1 by voriconazole contributes to these visual disturbances. 相似文献
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Glycoproteins in human serum play fundamental roles in many biological processes, and also have clinical value as biomarkers for disease progression and treatment. In this study, we isolated glycoproteins from the sera of three healthy individuals and three lung adenocarcinoma patients using multilectin affinity chromatography. The recovered glycoproteins were subjected to treatment with peptide-N-glycosidase F (PNGase F) and in-gel digestion by trypsin. Tryptic peptides were analyzed by nano-LC coupled to ESI-MS/MS and the MS/MS spectra were processed by Bioworks 3.2 and an in-house bioinformatics tool, ProtAn. Approximately 90% of the proteins identified contained more than one potential glycosylation site. Comparison of the serum glycoproteome of healthy and adenocarcinoma individuals revealed 38 cancer-selective proteins. Among them, 60% have previously been reported as low abundance proteins in human sera. We identified several cancer-selective proteins that have been previously characterized as potential indicators of lung cancer in serum or plasma, including haptoglobin (HP), inter-alpha-trypsin inhibitor heavy chain 4 (ITI-H4), complement C3 precursor, and leucine-rich alpha-2-glycoprotein. In addition, plasma kallikrein (KLKB1) and inter-alpha-trypsin inhibitor heavy chain 3 (ITI-H3) were identified as being potentially elevated in the lung cancer group, and were validated by Western blot analysis. Furthermore, approximately 18 kDa plasma kallirein protein fragment was detected at high levels in 25 out of 28 adenocarcinoma patients, while one of the eight normal individuals showed moderate positive. The results suggest that KLKB1 represents a potential candidate serum biomarker of lung cancer. 相似文献
35.
Kim MH Kim MO Heo JS Kim JS Han HJ 《Apoptosis : an international journal on programmed cell death》2008,13(2):295-304
This study examined the effect of acetylcholine (ACh) on the hypoxia-induced apoptosis of mouse embryonic stem (ES) cells.
Hypoxia (60 h) decreased both the cell viability and level of [3H] thymidine incorporation, which were prevented by a pretreatment with ACh. However, the atropine (ACh receptor [AChR] inhibitor)
treatment blocked the protective effect of ACh. Hypoxia (90 min) increased the intracellular level of reactive oxygen species
(ROS). On the other hand, ACh inhibited the hypoxia-induced increase in ROS, which was blocked by an atropine treatment. Subsequently,
the hypoxia-induced ROS increased the level of p38 mitogen activated protein kinase (MAPK) and Jun-N-terminal kinase (JNK)
phosphorylation, which were inhibited by the ACh pretreatment. Moreover, hypoxic exposure (90 min) increased the level of
nuclear factor-κB (NF-κB) phosphorylation, which was blocked by a pretreatment with SB 203580 (p38 MAPK inhibitor) or SP 600125
(JNK inhibitor). However, hypoxia (60 h) decreased the protein levels of Bcl-2 and c-IAPs (cellular inhibitor of apoptosis
proteins) but increased the level of caspase-3 activation. All these effects were inhibited by a pretreatment with ACh. In
conclusion, ACh prevented the hypoxia-induced apoptosis of mouse ES cells by inhibiting the ROS-mediated p38 MAPK and JNK
activation as well as the regulation of Bcl-2, c-IAPs, and caspase-3.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
36.
Jae-Yoo Choi Yong-Dae Gwon Jeong-Ki Kim Yeon-Dong Cho Yoon-Ki Heo Han-Sam Cho Tae-Jin Choi Ha-Ryoung Poo Yu-Kyoung Oh Young Bong Kim 《PloS one》2013,8(11)
Despite the advantages of DNA vaccines, overcoming their lower efficacy relative to that of conventional vaccines remains a challenge. Here, we constructed a human endogenous retrovirus (HERV) envelope-coated, nonreplicable, baculovirus-based HA vaccine against swine influenza A/California/04/2009(H1N1) hemagglutin (HA) (AcHERV-sH1N1-HA) as an alternative to conventional vaccines and evaluated its efficacy in two strains of mice, BALB/c and C57BL/6. A commercially available, killed virus vaccine was used as a positive control. Mice were intramuscularly administered AcHERV-sH1N1-HA or the commercial vaccine and subsequently given two booster injections. Compared with the commercial vaccine, AcHERV-sH1N1-HA induced significantly higher levels of cellular immune responses in both BALB/c and C57BL/6 mice. Unlike cellular immune responses, humoral immune responses depended on the strain of mice. Following immunization with AcHERV-sH1N1-HA, C57BL/6 mice showed HA-specific IgG titers 10- to 100-fold lower than those of BALB/c mice. In line with the different levels of humoral immune responses, the survival of immunized mice after intranasal challenge with sH1N1 virus (A/California/04/2009) depended on the strain. After challenge with 10-times the median lethal dose (MLD50) of sH1N1 virus, 100% of BALB/c mice immunized with the commercial vaccine or AcHERV-sH1N1-HA survived. In contrast, C57BL/6 mice immunized with AcHERV-sH1N1-HA or the commercial vaccine showed 60% and 70% survival respectively, after challenge with sH1N1 virus. In all mice, virus titers and results of histological analyses of lung tissues were consistent with the survival data. Our results indicate the importance of humoral immune response as a major defense system against influenza viral infection. Moreover, the complete survival of BALB/c mice immunized with AcHERV-sH1N1-HA after challenge with sH1N1 virus suggests the potential of baculoviral vector-based vaccines to achieve an efficacy comparable to that of killed virus vaccines. 相似文献
37.
Myles S Faith Kathleen L Keller Patty Matz Susan L Johnson Rebecca Lewis Marie Alexandra Jorge Clare Ridley Helen Han Shoshanna Must Moonseong Heo Angelo Pietrobelli Steven B Heymsfield David B Allison 《Twin research》2002,5(5):472-475
"Project Grow-2-Gether" is a child nutrition study of same-sex, 3- to 7-year-old monozygotic and dizygotic twin pairs. The study attempts to bridge two bodies of literature that have rarely interfaced with respect to obesity and ingestive behavior: the first being behavioral genetic approaches to obesity-related traits, and the second being developmental approaches focusing on parent-child relationships. The overarching aim of Project Grow-2-Gether is to disentangle genetic from potential home-environmental influences on child eating behavior and body fat. This paper reviews the rationale for Project Grow-2-Gether, its procedures, and core phenotypic measurement battery. A focus of the study is acquisition of controlled food intake measurements obtained in the laboratory, measurement of specific home environmental variables, and multi-method evaluation of parent-child feeding relations. Future directions may involve longitudinal assessment of child growth and molecular analyses for specific genes that influence child eating behavior. 相似文献
38.
Induction of Betalain Pigmentation in Hairy Roots of Red Beet under Different Radiation Sources 总被引:5,自引:0,他引:5
The effects of aluminum on lipid peroxidation and activities of antioxidative enzymes were investigated in detached rice leaves treated with 0 to 5 mM AlCl3 at pH 4.0 in the light. AlCl3 enhanced the content of malondialdehyde but not the content of H2O2. Superoxide dismutase activity was reduced by AlCl3, while catalase and glutathione reductase activities were increased. Peroxidase and ascorbate peroxidase activities were increased only after prolonged treatment, when toxicity occurred. The results give evidence that Al treatment caused oxidative stress and in turn, it caused lipid peroxidation. 相似文献
39.
Yang YX Heo S Jin Z Yun JH Choi JY Yoon SY Park MS Yang BK Chae BJ 《Animal reproduction science》2009,112(3-4):199-214
Modern genotype primiparous and multiparous sows (Yorkshire x Landrace, n=48) were used to evaluate effects of dietary lysine intake during late gestation and lactation, and their interaction on reproductive performance. Sows were randomly allotted to two gestation lysine (G, 0.6% or 0.8% lysine) treatments based on parity in a 2 x 2 factorial arrangement, and each treatment had 12 replicates comprising 1 sow. Then all the sows were assigned to two lactation lysine (L, 1.0% or 1.3% lysine) treatments within parity and gestation treatments in a 2 x 2 x 2 factorial design, and each treatment comprised six replicates with 1 sow/replicate during lactation. Feeding higher lysine level during gestation increased sow body weight and backfat thickness (P=0.001) and body condition was better (P=0.001) in multiparous than that of primiparous sows. Both of the lysine levels during lactation and parity influenced sow body condition and reproductive performance (P<0.05). Higher lysine intake during lactation increased the concentrations of total solids (P=0.024), protein (P=0.001) and solids not-fat (P=0.042) in colostrum and total solids (P=0.001), protein (P=0.001), fat (P=0.001) and solids not-fat (P=0.005) in milk. Protein concentration of milk was greater (P=0.001) in multiparous sows than that of primiparous sows. Feeding of high lysine diets resulted in an increment of plasma urea N (P=0.010; P=0.047) and a decrease of creatinine (P=0.045; P=0.002) on the day of postfarrowing and weaning, respectively. Furthermore, as lysine intake increased, the secretions of insulin, FSH, and LH were increased (P<0.05) and multiparous sows showed higher (P<0.05) concentrations of FSH and LH pulses on the day of postfarrowing and weaning, respectively. These results indicated that higher lysine intake than that recommended by NRC [NRC, 1998. Nutrient Requirements of Swine, 10th ed. National Academy Press, 458 Washington, DC] could improve sow performance during late gestation and lactation. Furthermore primiparous sows need higher lysine intake than multiparous sows. Moreover, nutritional impacts on reproduction may be mediated in part through associated effects on circulating LH concentration. 相似文献
40.
Heo HJ Cho HY Hong B Kim HK Heo TR Kim EK Kim SK Kim CJ Shin DH 《Molecules and cells》2002,13(1):5-11
Amyloid beta protein (Abeta) increases free radical production and lipid peroxidation in PC12 nerve cells, leading to apoptosis and cell death. The effect of ursolic acid from Origanum majorana L. on Abeta-induced neurotoxicity was investigated using PC12 cells. Pretreatment with isolated ursolic acid and vitamin E prevented the PC12 cell from reactive oxygen species (ROS) toxicity that is mediated by Abeta. The ursolic acid resulted in decreased Abeta toxicity assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), lactate dehydrogenase (LDH), and trypan blue assay. Thus, treatment with these antioxidants inhibited the Abeta-induced neurotoxic effect. Therefore, these results indicate that micromolar Abeta-induced oxidative cell death is reduced by ursolic acid from Origanum majorana L. 相似文献