Obesity is linked to a low-level chronic inflammatory state that may contribute to the development of associated metabolic complications. Retinol-binding protein 4 (RBP4) is an adipokine associated with parameters of obesity including insulin resistance indices, body mass index, waist circumference, lipid profile, and recently, with circulating inflammatory factors. Due to the infiltration of adipose tissue in obesity by macrophages derived from circulating monocytes and, on the other hand, the existence of a close genetic relationship between adipocytes and macrophages, we decided to examine if RBP4 is expressed in monocytes and/or primary human macrophages. While we did not detect expression of RBP4 in undifferentiated monocytes, RBP4 expression became evident during the differentiation of monocytes into macrophages and was highest in differentiated macrophages. Once we demonstrated the expression of RBP4 in macrophages, we checked if RBP4 expression could be regulated by inflammatory stimuli such as tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), or the endotoxin lipopolysaccharide (LPS). We observed that while RBP4 expression was strongly inhibited by TNF-α and LPS, it was not affected by IL-6. Our results highlight the complexity behind the regulation of this adipokine and demonstrate that RBP4 expression in macrophages could be modulated by inflammatory stimuli., M. Broch ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
The paper deals with the problem of finding the field of force that generates a given ($N-1$)-parametric family of orbits for a mechanical system with $N$ degrees of freedom. This problem is usually referred to as the inverse problem of dynamics. We study this problem in relation to the problems of celestial mechanics. We state and solve a generalization of the Dainelli and Joukovski problem and propose a new approach to solve the inverse Suslov's problem. We apply the obtained results to generalize the theorem enunciated by Joukovski in 1890, solve the inverse Stäckel problem and solve the problem of constructing the potential-energy function $U$ that is capable of generating a bi-parametric family of orbits for a particle in space. We determine the equations for the sought-for function $U$ and show that on the basis of these equations we can define a system of two linear partial differential equations with respect to $U$ which contains as a particular case the Szebehely equation. We solve completely a special case of the inverse dynamics problem of constructing $U$ that generates a given family of conics known as Bertrand's problem. At the end we establish the relation between Bertrand's problem and the solutions to the Heun differential equation. We illustrate our results by several examples.