25 research outputs found

    Analysis of a wild mouse promoter variant reveals a novel role for FcĪ³RIIb in the control of the germinal center and autoimmunity.

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    Genetic variants of the inhibitory Fc receptor FcĪ³RIIb have been associated with systemic lupus erythematosus in humans and mice. The mechanism by which Fcgr2b variants contribute to the development of autoimmunity is unknown and was investigated by knocking in the most commonly conserved wild mouse Fcgr2b promoter haplotype, also associated with autoimmune-prone mouse strains, into the C57BL/6 background. We found that in the absence of an AP-1-binding site in its promoter, FcĪ³RIIb failed to be up-regulated on activated and germinal center (GC) B cells. This resulted in enhanced GC responses, increased affinity maturation, and autoantibody production. Accordingly, in the absence of FcĪ³RIIb activation-induced up-regulation, mice developed more severe collagen-induced arthritis and spontaneous glomerular immune complex deposition. Our data highlight how natural variation in Fcgr2b drives the development of autoimmune disease. They also show how the study of such variants using a knockin approach can provide insight into immune mechanisms not possible using conventional genetic manipulation, in this case demonstrating an unexpected critical role for the activation-induced up-regulation of FcĪ³RIIb in controlling affinity maturation, autoantibody production, and autoimmunity

    Mesozoic and Cenozoic Sequence Chronostratigraphic Framework of European Basins, P. C. De Graciansky

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    Mutualisms are key components of biodiversity and ecosystem function, yet the forces maintaining them are poorly understood. We investigated the effects of removing large mammals on an antAcacia mutualism in an African savanna. Ten years of large-herbivore exclusion reduced the nectar and housing provided by plants to ants, increasing antagonistic behavior by a mutualistic ant associate and shifting competitive dominance within the plant-ant community from this nectardependent mutualist to an antagonistic species that does not depend on plant rewards. Trees occupied by this antagonist suffered increased attack by stem-boring beetles, grew more slowly, and experienced doubled mortality relative to trees occupied by the mutualistic ant. These results show that large mammals maintain cooperation within a widespread symbiosis and suggest complex cascading effects of megafaunal extinction

    EFFICIENCY AND SAFETY ASSESSMENT OF GENERIC ATORVASTATINE IN PATIENTS WITH HYPERLIPIDEMIA

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    Aim. To assess in a short-term study efficiency and safety of hypolipidemic therapy with atorvastatine generic, Tulip, in comparison with simvastatine generic, Vasilip, in hyperlipidemic patients.Material and methods. Open, randomized, comparative, cross over study included 87 patients with hyperlipidemia, who didnā€™t receive hypolipidemic drugs within 6 weeks, or followed hypolipidemic diet for 4 weeks. Each patient received therapy with one of the studied drugs within 6 weeks. Then after 4-week wash-out period the second therapy with the other drug was held. Consequence of courses with each drug was set by randomization. Initial dose of both drugs was 10 mg daily. Dose was adjusted after 3 weeks. The dose was increased to 20 mg daily if cholesterol of low density lipoproteid (CLDL) hadnā€™t reached target level (&lt; 115 mg/dl). of Treatment safety was assessed on the basis of clinical data, hepatic enzymes activity and creatine phosphokinase levels.Results. It is shown, that to reach target figures of plasma lipid spectrum, Vasilip dose was increased significantly more often, than Tulip dose. Average Tulip dose after titration was 14,8 mg daily, Vasilip dose ā€“ 15,6 mg daily. Patients with initially higher level of triglycerides (TG &gt; 170 mg/dl) after 6 weeks with Tulip treatment showed TG reduction by 38% and with Vasilip treatment ā€“ by 20%. Both drugs showed good tolerance, no significant differences in number of side-effects were observed.Conclusion. 6-week treatment with atorvastatine generic Tulip shows significant hypolipidemic effect, which appears in significant reduction of CLDL, total cholesterol, TG compared to the initial levels. Degree of total cholesterol reduction is significantly higher with Tulip treatment compared to Vasilip treatment. Analyses shown that target levels of the assessed figures were reached in more patients, treated with Tulip. Side-effects in Tulip treatment were not severe.</p
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