1,057 research outputs found
Plasmodium yoelii infection of BALB/c mice results in expansion rather than induction of CD4+ Foxp3+ regulatory T cells
Recently, we demonstrated elevated numbers of CD4(+) Foxp3(+) regulatory T (Treg) cells in Plasmodium yoeliiâinfected mice contributing to the regulation of antiâmalarial immune response. However, it remains unclear whether this increase in Treg cells is due to thymusâderived Treg cell expansion or induction of Treg cells in the periphery. Here, we show that the frequency of Foxp3(+) Treg cells expressing neuropilinâ1 (Nrpâ1) decreased at early timeâpoints during P. yoelii infection, whereas percentages of Helios(+) Foxp3(+) Treg cells remained unchanged. Both Foxp3(+) Nrpâ1(+) and Foxp3(+) Nrpâ1(â) Treg cells from P. yoeliiâinfected mice exhibited a similar Tâcell receptor VÎČ chain usage and methylation pattern in the Tregâspecific demethylation region within the foxp3 locus. Strikingly, we did not observe induction of Foxp3 expression in Foxp3(â) T cells adoptively transferred to P. yoeliiâinfected mice. Hence, our results suggest that P. yoelii infection triggered expansion of naturally occurring Treg cells rather than de novo induction of Foxp3(+) Treg cells
A method to measure the mirror reflectivity of a prime focus telescope
We have developed a method to measure the mirror reflectivity of telescopes. While it is relatively easy to measure the local reflectivity of the mirror material, it is not so straightforward to measure the amount of light that it focuses in a spot of a given diameter. Our method is based on the use of a CCD camera that is fixed on the mirror dish structure and observes simultaneously part of the telescope's focal plane and the sky region around its optical axis. A white diffuse reflecting disk of known reflectivity is fixed in the telescopes focal plane. During a typical reflectivity measurement the telescope is directed to a selected star. The CCD camera can see two images of the selected star, one directly and another one as a spot focused by the mirror on the white disk. The ratio of the reflected starlight integrated by the CCD from the white disk to the directly measured one provides a precise result of the product of (mirror area x mirror reflectivity)
The role of venous valves in pressure shielding
This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
The Epitheliome: agent-based modelling of the social behaviour of cells
We have developed a new computational modelling paradigm for predicting the emergent behaviour
resulting from the interaction of cells in epithelial tissue. As proof-of-concept, an agent-based model,
in which there is a one-to-one correspondence between biological cells and software agents, has been
coupled to a simple physical model. Behaviour of the computational model is compared with the
growth characteristics of epithelial cells in monolayer culture, using growth media with low and
physiological calcium concentrations. Results show a qualitative fit between the growth characteristics
produced by the simulation and the in vitro cell models
Expansion of the ligand knowledge base for chelating P,P-donor ligands (LKB-PP)
[Image: see text] We have expanded the ligand knowledge base for bidentate P,P- and P,N-donor ligands (LKB-PP, Organometallics2008, 27, 1372â1383) by 208 ligands and introduced an additional steric descriptor (nHe(8)). This expanded knowledge base now captures information on 334 bidentate ligands and has been processed with principal component analysis (PCA) of the descriptors to produce a detailed map of bidentate ligand space, which better captures ligand variation and has been used for the analysis of ligand properties
Development of atopic sensitization in Finnish and Estonian children : A latent class analysis in a multicenter cohort
Background: The prevalence of atopy is associated with a Western lifestyle, as shown by studies comparing neighboring regions with different socioeconomic backgrounds. Atopy might reflect various conditions differing in their susceptibility to environmental factors. Objective: We sought to define phenotypes of atopic sensitization in early childhood and examine their association with allergic diseases and hereditary background in Finland and Estonia. Methods: The analysis included 1603 Finnish and 1657 Estonian children from the DIABIMMUNE multicenter young children cohort. Specific IgE levels were measured at age 3, 4, and 5 years, respectively, and categorized into 3 CAP classes. Latent class analysis was performed with the statistical software package poLCA in R software. Results: Both populations differed in terms of socioeconomic status and environmental determinants, such as pet ownership, farm-related exposure, time spent playing outdoors, and prevalence of allergic diseases (all P Conclusion: Despite profound differences in environmental exposures, there might exist genuine patterns of atopic sensitization. The distribution of these patterns might determine the contribution of atopic sensitization to disease onset.Peer reviewe
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