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121.
Marit S. Nenseter Ingunn Narverud Asgeir Græsdal Martin P. Bogsrud Bente Halvorsen Leiv Ose Pål Aukrust Kirsten B. Holven 《Cytokine》2013,61(1):194-198
ObjectiveMatrix degradation within an atherosclerotic plaque is an important pathogenic factor in atherosclerosis, and is largely modulated by the balance between matrix metalloproteinases (MMPs) and their endogenous inhibitors (i.e., tissue inhibitor of MMPs [TIMPs]). Familial hypercholesterolemia (FH) is a rare inherited disorder associated with premature coronary heart disease. The aim of the present study was to examine MMP-9 and TIMP-1 on plasma and cellular mRNA levels in homozygous FH patients (n = 7) compared with age- and sex-matched heterozygous FH patients (n = 6), and with healthy subjects (n = 7), and to test whether once-weekly LDL-apheresis (three consecutive sessions) of homozygous FH patients show short-term effects on these variables.ResultsThe main findings were that (i) Compared to healthy control subjects, homozygous FH patients have significantly higher serum levels of MMP-9 and lower levels of TIMP-1, and consequently significantly higher MMP-9/TIMP-1 ratio, potentially reflecting higher MMP-9 activity. (ii) Peripheral blood mononuclear cells (PBMC) isolated from FH homozygotes have significantly higher mRNA levels of MMP-9 compared to cells from heterozygotes. (iii) TNFα-stimulated PBMC from FH homozygotes released borderline-significantly more MMP-9 than cells from heterozygotes and healthy controls. (iv) LDL-apheresis (one day before treatment versus fifteen days later, on the day after the weekly treatment) had no significant short-term effect on any of the MMP-9 and TIMP-1 variables measured in serum and cells.ConclusionsThe data may suggest that homozygous FH patients have an enhanced matrix degrading potential as compared with heterozygous FH patients and healthy controls, potentially contributing to the increased cardiovascular risk observed in these patients. 相似文献
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Marit JS Weber LP 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2011,154(1):14-18
While swimming endurance (critical swimming speed or U(crit)) and lipid stores have both been reported to acutely decrease after exposure to a variety of toxicants, the relationship between these endpoints has not been clearly established. In order to examine these relationships, adult zebrafish (Danio rerio) were aqueously exposed to solvent control (ethanol) or two nominal concentrations of 2,4-dinitrophenol (DNP), a mitochondrial electron transport chain uncoupler, for a 24-h period. Following exposure, fish were placed in a swim tunnel in clean water for swimming testing or euthanized immediately without testing, followed by analysis of whole body triglyceride levels. U(crit) decreased in both the 6 mg/L and 12 mg/L DNP groups, with 12 mg/L approaching the LC??. A decrease in tail beat frequency was observed without a significant change in tail beat amplitude. In contrast, triglyceride levels were elevated in a concentration-dependent manner in the DNP exposure groups, but only in fish subjected to swimming tests. This increase in triglyceride stores may be due to a direct interference of DNP on lipid catabolism as well as increased triglyceride production when zebrafish were subjected to the co-stressors of swimming and toxicant exposure. Future studies should be directed at determining how acute DNP exposure combines with swimming to cause alterations in triglyceride accumulation. 相似文献
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Marit Linnerud Bernt‐Erik Sæther Vidar Grøtan Steinar Engen David G. Noble Robert P. Freckleton 《Oikos》2013,122(8):1207-1216
Taylor’s power law, i.e. that the slope for the increase in variance with mean population size is between 1 and 2 at a logarithmic scale, provides one of the few quantitative relationships in population ecology, yet the underlying ecological mechanisms are only poorly understood. Stochastic theory of population dynamics predicts that demographic and environmental stochasticity will affect the slope differently. In a stable environment under the influence of demographic stochasticity alone the slope will be equal to 1. In large populations in which demographic variance will have a negligible effect on the dynamics the slope will approach 2. In addition, the slope will also be influenced by how the strength of density dependence is related to mean population size. To disentangle the relative contribution of these processes we estimate the mean‐variance relationship for a large number of populations of British birds. The variance in population size of most species decreased with the mean due to decreased influence of demographic stochasticity at larger population sizes. Interspecific differences in demographic stochasticity was the main factor influencing variation in slopes of Taylor’s power law among species through a significant negative relationship between the slope and demographic variance. In addition, slopes were influenced by interspecific variation in life history parameters such as adult survival and clutch size. These analyses show that Taylor’s power law is generated from an interplay between stochastic and density dependent factors, modulated by life history. 相似文献
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Anna Schorcht Tom L. G. M. van den Kerkhof Christopher A. Cottrell Joel D. Allen Jonathan L. Torres Anna-Janina Behrens Edith E. Schermer Judith A. Burger Steven W. de Taeye Alba Torrents de la Pea Ilja Bontjer Stephanie Gumbs Gabriel Ozorowski Celia C. LaBranche Natalia de Val Anila Yasmeen Per Johan Klasse David C. Montefiori John P. Moore Hanneke Schuitemaker Max Crispin Marit J. van Gils Andrew B. Ward Rogier W. Sanders 《Journal of virology》2020,94(24)
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Pim Cuijpers Marit Sijbrandij Sander L. Koole Gerhard Andersson Aartjan T. Beekman Charles F. Reynolds III 《World psychiatry》2013,12(2):137-148
Although psychotherapy and antidepressant medication are efficacious in the treatment of depressive and anxiety disorders, it is not known whether they are equally efficacious for all types of disorders, and whether all types of psychotherapy and antidepressants are equally efficacious for each disorder. We conducted a meta-analysis of studies in which psychotherapy and antidepressant medication were directly compared in the treatment of depressive and anxiety disorders. Systematic searches in bibliographical databases resulted in 67 randomized trials, including 5,993 patients that met inclusion criteria, 40 studies focusing on depressive disorders and 27 focusing on anxiety disorders. The overall effect size indicating the difference between psychotherapy and pharmacotherapy after treatment in all disorders was g=0.02 (95% CI: −0.07 to 0.10), which was not statistically significant. Pharmacotherapy was significantly more efficacious than psychotherapy in dysthymia (g=0.30), and psychotherapy was significantly more efficacious than pharmacotherapy in obsessive-compulsive disorder (g=0.64). Furthermore, pharmacotherapy was significantly more efficacious than non-directive counseling (g=0.33), and psychotherapy was significantly more efficacious than pharmacotherapy with tricyclic antidepressants (g=0.21). These results remained significant when we controlled for other characteristics of the studies in multivariate meta-regression analysis, except for the differential effects in dysthymia, which were no longer statistically significant. 相似文献
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