Present and Future Fiscal Policy Problems in the Czech Republic

This paper is focused . using the example of the Czech Republic since 1993 . on a description of the hidden risks, implicitly existing in the system of public finances during the transition period (from a centrally planned towards market economy). The starting assumption is that public budgets have in time of economic transition certain specific functions. These consist explicitly in supporting the transitional process by transferring part of the economic and social costs, attached to it, over time and various categories of population. These functions are to be carried out at time, when the economic performance of those countries tends to be rather poor and the revenue side of the budgets is not buoyant. Since the financial capacity of the budget is restraint, governments try to find ways by which transition functions could be carried out while their financing would not take the form of instant cash outlays. Evidence of the Czech Republic suggests that measures, conceived to meet the expectations attached to the budget in respect to part of the transitional costs, though conceived originally as temporary, tend over time to become of a permanent nature. Issues such as a risk of moral hazard then occur. The analysis also points to the fact that these sorts of phenomena may not be the only factor that contributed to the deterioration of the Czech public finance in recent years. The evidence of fiscal developments in quite a number of transitional economies suggests that elements of these features tend to exist in most of those countries.Fiscal Policy, Czech Republic

Toll-like receptor signaling in thymic epithelium controls monocyte-derived dendritic cell recruitment and Treg generation

The development of thymic regulatory T cells (Treg) is mediated by Aire-regulated self-antigen presentation on medullary thymic epithelial cells (mTECs) and dendritic cells (DCs), but the cooperation between these cells is still poorly understood. Here we show that signaling through Toll-like receptors (TLR) expressed on mTECs regulates the production of specific chemokines and other genes associated with post-Aire mTEC development. Using single-cell RNA-sequencing, we identify a new thymic CD14(+)Sirp alpha (+) population of monocyte-derived dendritic cells (CD14(+)moDC) that are enriched in the thymic medulla and effectively acquire mTEC-derived antigens in response to the above chemokines. Consistently, the cellularity of CD14(+)moDC is diminished in mice with MyD88-deficient TECs, in which the frequency and functionality of thymic CD25(+)Foxp3(+) Tregs are decreased, leading to aggravated mouse experimental colitis. Thus, our findings describe a TLR-dependent function of mTECs for the recruitment of CD14(+)moDC, the generation of Tregs, and thereby the establishment of central tolerance. Immune tolerance is mediated by the deletion of autoreactive T cells via medullary thymic epithelial cells (mTEC) and dendritic cells (DC), and by the induction of regulatory T cells (Treg). Here the authors show that mTEC receiving toll-like receptor signaling control the recruitment of CD14(+)Sirp alpha (+) DC population that is capable of inducing Treg for establishing tolerance

Role of actin cytoskeleton at multiple levels of T cell activation

Actin cytoskeleton is an essential cellular structure that is involved in many physiological aspects, including T cell antigenic responses. In has been proposed that actin modulates biophysical parameters of the antigen recognition, forms a barrier inhibiting spontaneous signaling in resting T cells, facilitates TCR signal transduction, stabilizes contacts between T cells and antigen presenting cells, and contributes to the establishment of the antigen affinity threshold. In this review, we discuss the role of actin cytoskeleton at these particular levels of T cell activation

Opposing effects of actin signaling and LFA-1 on establishing the affinity threshold for inducing effector T-cell responses in mice

Mature CD8(+) T cells use a narrow antigen affinity threshold to generate tissue-infiltrating cytotoxic effector T cells and induce autoimmune pathology, but the mechanisms that establish this antigen affinity threshold are poorly understood. Only antigens with affinities above the threshold induce stable contacts with APCs, polarization of a T cell, and asymmetric T-cell division. Previously published data indicate that LFA-1 inside-out signaling might be involved in establishing the antigen affinity threshold. Here, we show that subthreshold antigens weakly activate all major distal TCR signaling pathways. Low-affinity antigens are more dependent on LFA-1 than suprathreshold antigens. Moreover, augmenting the inside-out signaling by hyperactive Rap1 does not increase responses to the subthreshold antigens. Thus, LFA-1 signaling does not contribute to the affinity-based antigen discrimination. However, we found that subthreshold antigens do not induce actin rearrangement toward an APC, mediated by Rho-family GTPases, Cdc42, and Rac. Our data suggest that Rac and Cdc42 contribute to the establishment of the antigen affinity threshold in CD8(+) T cells by enhancing responses to high-affinity antigens, or by reducing the responses to low-affinity antigens

Identification of GC-rich LAT genes in birds

Linker for activation of T cells (LAT) plays a key role in T-cell antigenic signaling in mammals. Accordingly, LAT orthologues were identified in the majority of vertebrates. However, LAT orthologues were not identified in most birds. In this study, we show that LAT gene is present in genomes of multiple extant birds. It was not properly assembled previously because of its GC-rich content. LAT expression is enriched in lymphoid organs in chicken. The analysis of the coding sequences revealed a strong conservation of key signaling motifs in LAT between chicken and human. Overall, our data indicate that mammalian and avian LAT genes are functional homologues with a common role in T-cell signaling

Identification of GC-rich LAT genes in birds.

Linker for activation of T cells (LAT) plays a key role in T-cell antigenic signaling in mammals. Accordingly, LAT orthologues were identified in the majority of vertebrates. However, LAT orthologues were not identified in most birds. In this study, we show that LAT gene is present in genomes of multiple extant birds. It was not properly assembled previously because of its GC-rich content. LAT expression is enriched in lymphoid organs in chicken. The analysis of the coding sequences revealed a strong conservation of key signaling motifs in LAT between chicken and human. Overall, our data indicate that mammalian and avian LAT genes are functional homologues with a common role in T-cell signaling

Self-assembly, drug encapsulation, and cellular uptake of block and gradient copolymers of 2-methyl-2-oxazine and 2-n-propyl/butyl-2-oxazoline

Self-assembled amphiphilic polymers have been extensively studied for various biomedical applications, as they show advantageous properties for diagnosis and therapy. In this work, we extensively compared amphiphilic copolymers of the hydrophilic monomer 2-methyl-2-oxazine (MeOzi) and the thermoresponsive or hydrophobic monomers 2-propyl-2-oxazoline (PrOx) or 2-butyl-2-oxazoline (BuOx) in both block and gradient monomer distributions. Such a head-to-head comparison between block and gradient copolymers, which has thus far been mostly missing in the available literature, should provide important insight into the differences and similarities between these two architectures. We investigated the properties of our polymers using a wide array of analytical methods, including dynamic light scattering (DLS), small-angle neutron (SANS) and X-ray scattering (SAXS), one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) spectroscopy, transmission electron microscopy (TEM), drug loading (DL), cellular uptake, and cytotoxicity studies. Most of the studied polymers formed self-assembled nanoparticles, but their properties varied with the monomer ratio, polymer length, and polymer architecture, and these factors could be used to fine-tune the properties of the polymer to meet the demands of the desired application. Both block and gradient copolymers showed similar critical association concentrations and DL properties for the antituberculosis drug rifampicin. Finally, we confirmed that the nanoparticles could be internalized by macrophages, which indicates great potential for the utilization of these nanoparticles in drug delivery

Glycogen-graft-poly(2-alkyl-2-oxazolines) - The new Versatile Biopolymer-Based Thermoresponsive Macromolecular Toolbox

his study is focused on thermoresponsive glycogen-graft-poly(2-alkyl-2-oxazolines), a new group of nanostructured hybrid dendrimeric stimuli-responsive polymers connecting the body's own biodegradable polysaccharidic dendrimer glycogen with the widely tuneable thermoresponsive behavior of polypeptide-analogic poly(2-alkyl-2-oxazolines), which are known to be biocompatible. Glycogen-graft-poly(2-alkyl-2-oxazolines) were prepared by a simple one-pot two-step procedure involving cationic ring-opening polymerization of 2-alkyl-2-oxazolines followed by termination of the living cationic ends with sodium glycogenate. As confirmed by light and X-ray scattering, as well as cryo-transmission electron microscopy, the grafted dendrimer structure allows easy adjustment of the cloud point temperature, the concentration dependence and nanostructure of the self-assembled phase separated polymer by crosstalk during graft composition, the graft length and the grafting density, in a very wide range