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91.
DeMorrow S Glaser S Francis H Venter J Vaculin B Vaculin S Alpini G 《The Journal of biological chemistry》2007,282(17):13098-13113
Cholangiocarcinomas are devastating cancers of biliary origin with limited treatment options. Modulation of the endocannabinoid system is being targeted to develop possible therapeutic strategies for a number of cancers; therefore, we evaluated the effects of the two major endocannabinoids, anandamide and 2-arachidonylglycerol, on numerous cholangiocarcinoma cell lines. Although anandamide was antiproliferative and proapoptotic, 2-arachidonylglycerol stimulated cholangiocarcinoma cell growth. Specific inhibitors for each of the cannabinoid receptors did not prevent either of these effects nor did pretreatment with pertussis toxin, a G(i/o) protein inhibitor, suggesting that anandamide and 2-arachidonylglycerol did not exert their diametric effects through any known cannabinoid receptor or through any other G(i/o) protein-coupled receptor. Using the lipid raft disruptors methyl-beta-cyclodextrin and filipin, we demonstrated that anandamide, but not 2-arachidonylglycerol, requires lipid raft-mediated events to inhibit cellular proliferation. Closer inspection of the lipid raft structures within the cell membrane revealed that although anandamide treatment had no observable effect 2-arachidonylglycerol treatment effectively dissipated the lipid raft structures and caused the lipid raft-associated proteins lyn and flotillin-1 to disperse into the surrounding membrane. In addition, anandamide, but not 2-arachidonylglycerol, induced an accumulation of ceramide, which was required for anandamide-induced suppression of cell growth. Finally we demonstrated that anandamide and ceramide treatment of cholangiocarcinoma cells recruited Fas and Fas ligand into the lipid rafts, subsequently activating death receptor pathways. These findings suggest that modulation of the endocannabinoid system may be a target for the development of possible therapeutic strategies for the treatment of this devastating cancer. 相似文献
92.
Heritability and genetic correlations of metabolic disease-related phenotypes in Mexico: preliminary report from the GEMM Family Study 总被引:1,自引:0,他引:1
Bastarrachea RA Kent JW Rozada G Cole SA López-Alvarenga JC Aradillas C Brito-Zurita O Cerda-Flores RM Ibarra-Costilla E Gallegos E Laviada-Molina H Hernandez-Escalante V Rosas J Machado A Vadillo F Ramos M Lazalde B Santa-Olalla J MacCluer JW Comuzzie AG 《Human biology; an international record of research》2007,79(1):121-129
Cardiovascular disease (CVD) is a major cause of mortality in the Republic of Mexico, and metabolic syndrome, a complex of CVD risk factors, is increasingly prevalent. To date, however, there have been few studies of the genetic epidemiology of metabolic syndrome in Mexico. As a first step in implementing the GEMM Family Study, a large, multicenter collaborative study, we recruited 375 individuals in 21 extended families, without ascertainment on disease, at 9 medical institutions across Mexico. Participants were measured for anthropometric (stature, weight, waist circumference) and hemodynamic (blood pressure, heart rate) phenotypes; glucose, cholesterol, and triglyceride levels were measured in fasting blood. Variance components-based quantitative genetic analyses were performed using SOLAR. All phenotypes except diastolic blood pressure were significantly heritable. Consistent with the definition of metabolic syndrome, many phenotypes exhibited significant environmental correlation, and significant genetic correlations were found between measures of adiposity and fasting glucose and fasting triglyceride levels. These preliminary data represent the first heritability estimates for many of these phenotypes in the Republic of Mexico and indicate that this study design offers excellent power for future gene discovery relative to metabolic disease. 相似文献
93.
Teng M Johnson MD Thomas C Kiel D Lakis JN Kercher T Aytes S Kostrowicki J Bhumralkar D Truesdale L May J Sidelman U Kodra JT Jørgensen AS Olesen PH de Jong JC Madsen P Behrens C Pettersson I Knudsen LB Holst JJ Lau J 《Bioorganic & medicinal chemistry letters》2007,17(19):5472-5478
Following our previous publication describing the biological profiles, we herein describe the structure-activity relationships of a core set of quinoxalines as the hGLP-1 receptor agonists. The most potent and efficacious compounds are 6,7-dichloroquinoxalines bearing an alkyl sulfonyl group at the C-2 position and a secondary alkyl amino group at the C-3 position. These findings serve as a valuable starting point for the discovery of more drug-like small molecule agonists for the hGLP-1 receptor. 相似文献
94.
95.
Shelley A Caltharp Charmaine U Pira Noboru Mishima Erik N Youngdale David S McNeill Boleslaw H Liwnicz Kerby C Oberg 《BMC developmental biology》2007,7(1):32
Background
Nogo-A, a myelin-associated protein, inhibits neurite outgrowth and abates regeneration in the adult vertebrate central nervous system (CNS) and may play a role in maintaining neural pathways once established. However, the presence of Nogo-A during early CNS development is counterintuitive and hints at an additional role for Nogo-A beyond neurite inhibition. 相似文献96.
97.
98.
Chung MC Jorgensen SC Tonry JH Kashanchi F Bailey C Popov S 《FEMS immunology and medical microbiology》2011,62(2):173-181
The fibrinolytic system is often the target for pathogenic bacteria, resulting in increased fibrinolysis, bacterial dissemination, and inflammation. The purpose of this study was to explore whether proteases NprB and InhA secreted by Bacillus anthracis could activate the host's fibrinolytic system. NprB efficiently activated human pro-urokinase plasminogen activator (pro-uPA), a key protein in the fibrinolytic cascade. Conversely, InhA had little effect on pro-uPA. Plasminogen activator inhibitors (PAI)-1, 2 and the uPA receptor were also targets for NprB in vitro. InhA efficiently degraded the thrombin-activatable fibrinolysis inhibitor (TAFI) in vitro. Mice infected with B. anthracis showed a significant decrease in blood TAFI levels. In another mouse experiment, animals infected with isogenic inhA deletion mutants restored TAFI levels, while the levels in the parent strain decreased. We propose that NprB and InhA may contribute to the activation of the fibrinolytic system in anthrax infection. 相似文献
99.
The functional significance of allometric change in reptiles has received limited attention and the reason for such changes has been regarded as ‘obscure’. In this paper we report data on the Australian Pogona barbata, the eastern bearded dragon, from across their range and review changes in allometric growth among juveniles, and adult males and females and consider the functional relevance of these changes. There were significant differences in the population for mass, tail length, tail width, rear leg length and jaw length. These differences were consistent with differences required in locomotor performance and thus habitat use, together with access to different preferred dietary components. 相似文献
100.
Lindemer BJ Bongard RD Hoffmann R Baumgardt S Gonzalez FJ Merker MP 《American journal of physiology. Lung cellular and molecular physiology》2011,300(5):L773-L780
The quinones duroquinone (DQ) and coenzyme Q(1) (CoQ(1)) and quinone reductase inhibitors have been used to identify reductases involved in quinone reduction on passage through the pulmonary circulation. In perfused rat lung, NAD(P)H:quinone oxidoreductase 1 (NQO1) was identified as the predominant DQ reductase and NQO1 and mitochondrial complex I as the CoQ(1) reductases. Since inhibitors have nonspecific effects, the goal was to use Nqo1-null (NQO1(-)/(-)) mice to evaluate DQ as an NQO1 probe in the lung. Lung homogenate cytosol NQO1 activities were 97 ± 11, 54 ± 6, and 5 ± 1 (SE) nmol dichlorophenolindophenol reduced·min(-1)·mg protein(-1) for NQO1(+/+), NQO1(+/-), and NQO1(-/-) lungs, respectively. Intact lung quinone reduction was evaluated by infusion of DQ (50 μM) or CoQ(1) (60 μM) into the pulmonary arterial inflow of the isolated perfused lung and measurement of pulmonary venous effluent hydroquinone (DQH(2) or CoQ(1)H(2)). DQH(2) efflux rates for NQO1(+/+), NQO1(+/-), and NQO1(-/-) lungs were 0.65 ± 0.08, 0.45 ± 0.04, and 0.13 ± 0.05 (SE) μmol·min(-1)·g dry lung(-1), respectively. DQ reduction in NQO1(+/+) lungs was inhibited by 90 ± 4% with dicumarol; there was no inhibition in NQO1(-/-) lungs. There was no significant difference in CoQ(1)H(2) efflux rates for NQO1(+/+) and NQO1(-/-) lungs. Differences in DQ reduction were not due to differences in lung dry weights, wet-to-dry weight ratios, perfusion pressures, perfused surface areas, or total DQ recoveries. The data provide genetic evidence implicating DQ as a specific NQO1 probe in the perfused rodent lung. 相似文献