225 research outputs found
IL-1 and T helper immune responses
CD4 T cells play a critical role in mediating adaptive immunity to a variety of pathogens as well as in tumor immunity. If not adequately regulated, CD4 T cells can be also involved in autoimmunity, asthma, and allergic responses. During TCR activation in a particular cytokine milieu, naïve CD4 T cells may differentiate into one of several lineages of T helper (Th) cells, including Th1, Th2, and Th17, as defined by their pattern of cytokine production and function. IL-1, the prototypic proinflammatory cytokine, has been shown to influence growth and differentiation of immunocompetent lymphocytes. The differential expression of IL-1RI on human CD4 T cell subsets confers distinct capacities to acquire specific effector functions. In this review, we summarize the role of IL-1 on CD4 T cells, in terms of differentiation, activation, and maintenance or survival
Synthesis of Ballistic Capture Corridors at Mars via Polynomial Chaos Expansion
The space sector is experiencing a flourishing growth and evidence is
mounting that the near future will be characterized by a large amount of
deep-space missions. In the last decade, CubeSats have granted affordable
access to space due to their reduced manufacturing costs compared to
traditional missions. At the present-day, most miniaturized spacecraft have
thus far been deployed into near-Earth orbits, but soon a multitude of
interplanetary CubeSats will be employed for deep-space missions as well.
Nevertheless, the current paradigm for deep-space missions strongly relies on
ground-based operations. Although reliable, this approach will rapidly cause
saturation of ground slots, thereby hampering the current momentum in space
exploration. At the actual pace, human-in-the-loop, flight-related operations
for deep-space missions will soon become unsustainable.
Self-driving spacecraft are challenging the current paradigm under which
spacecraft are piloted in interplanetary space. They are intended as machines
capable of traveling in deep space and autonomously reaching their destination.
In EXTREMA, these systems are used to engineer ballistic capture (BC), thereby
proving the effectiveness of autonomy in a complex scenario. The key is to
accomplish low-thrust orbits culminating in BC. For this, a bundle of BC orbits
named ballistic capture corridor (BCC) can be targeted far away from a planet.
To achieve BC at Mars without any a priori instruction, an inexpensive and
accurate method to construct BCC directly on board is required. Therefore,
granting spacecraft the capability to manipulate stable sets in order to
self-compute a BCC is crucial. The goal of the paper is to numerically
synthesize a corridor exploiting the polynomial chaos expansion (PCE)
technique, thereby applying a suited uncertainty propagation technique to BC
orbit propagation.Comment: EXTREMA - Engineering Extremely Rare Events in Astrodynamics for
Deep-Space Missions in Autonomy, European Research Council (ERC), European
Union (EU), Horizon 2020. The content of this document reflects only the
author's view. ERC is not responsible for any use that may be made of the
information it contain
MDA5-positive dermatomyositis: An uncommon entity in Europe with variable clinical presentations
Clinically amyopathic dermatomyositis (CADM), described almost 50Â years ago, is defined on the basis of still not validated criteria and characterized by skin findings almost without muscle weakness. Autoantibodies directed against the cytosolic pathogen sensor MDA5 (CADM 140) can mark this subtype of dermatomyositis which has been reported to associate, in particular ethnic groups, with severe progressive interstitial lung disease, poor prognosis and an hyperferritinemic status resembling hemophagocytic-like syndromes. MDA5 may be relevant in that Interferon-signature claimed to characterize inflammatory myopathies and dermatomyosits itself, but its role is not clear. However, the titre of anti-MDA5 autoantibodies seems to correlate with the outcome. In Caucasian populations the association between anti-MDA5 positive CADM and rapidly progressive interstitial lung disease seems to be weaker, but the limited numbers of patients described so far could explain the lack of statistical significance. As a fact, European patients with circulating anti-MDA5 autoantibodies may be clinically inhomogeneous and exhibit different rates of severity. The two patients affected by anti-MDA5 positive dermatomyositis described hereafter provide a clear example of the extreme variability of the disease in terms of laboratory findings and clinical features
The spectacle of the poor. Or: ‘Wow!! Awesome. Nice to know that people care!’
On the night of 14 November 2012, a police officer of the New York Police Department encountered a homeless person while performing his duties around Times Square. He gave him a pair of boots and while doing so, he was photographed by a tourist. The photo was posted on Facebook, receiving in a few days more than 1.6 million visits. The paper unfolds the reasons why this particular image and story have gone, as the media has put it, ‘viral’. The paper investigates the spaces that have emerged in the media elongation of DePrimo's practice of care and, introducing the notion of ‘spectacle of the poor’, it argues that this specific case simplifies the dominant western framings around matter of ‘caring for the poor’. The political and cultural consequences of these framings are investigated, and reflections on how to tackle them provided.This is the author accepted manuscript. The final version is available from Taylor & Francis via http://dx.doi.org/10.1080/14649365.2014.91674
A study on the stability of carbon nanoforms–polyimidazolium network hybrids in the conversion of co2 into cyclic carbonates:Increase in catalytic activity after reuse
Three different carbon nanoforms (CNFs), single-walled and multi-walled carbon nanotubes (SWCNTs, MWCNTs) and carbon nanohorns (CNHs), have been used as supports for the direct polymerization of variable amounts of a bis-vinylimidazolium salt. Transmission electron microscopy confirmed that all CNFs act as templates on the growth of the polymeric network, which perfectly covers the nanocarbons forming a cylindrical (SWCNTs, MWCNTs) or spherical (CNHs) coating. The stability of these hybrid materials was investigated in the conversion of CO(2) into cyclic carbonate under high temperature and CO(2) pressure. Compared with the homopolymerized monomer, nanotube-based materials display an improved catalytic activity. Beside the low catalytic loading (0.05–0.09 mol%) and the absence of Lewis acid co-catalysts, all the materials showed high TON values (up to 1154 for epichlorohydrin with SW-1:2). Interestingly, despite the loss of part of the polymeric coating for crumbling or peeling, the activity increases upon recycling of the materials, and this behaviour was ascribed to their change in morphology, which led to materials with higher surface areas and with more accessible catalytic sites. Transmission electron microscopy analysis, along with different experiments, have been carried out in order to elucidate these findings
Au/CeO2 Photocatalyst for the Selective Oxidation of Aromatic Alcohols in Water under UV, Visible and Solar Irradiation
Au nanoparticles supported on CeO2 have been prepared and investigated as photocatalysts for the photocatalytic selective oxidation of benzyl alcohol and 4-methoxybenzyl alcohol to the correspondent benzaldehydes, in aqueous suspensions and room conditions under UV, visible and
natural solar light irradiation. Au nanoparticles have been supported by impregnation (1 and 3 wt.%) on two types of CeO2 (i.e., a commercial one and a home prepared oxide obtained in the presence of NaOH as precipitation agent). The Au impregnated samples showed strong visible radiation
absorption at 565–570 nm associated to localized surface plasmon resonance (LSPR). The bare CeO2 samples are activated by UV light and resulted virtually inactive under visible irradiation, whereas the presence of Au improved both the conversion of the alcohols and the selectivity of the reaction
towards the aldehyde, giving rise to good results, particularly under visible and natural solar light irradiation. The activity of the materials increased by increasing the Au content
Th17 and Th1 Lymphocytes in Oligoarticular Juvenile Idiopathic Arthritis
In the last years much attention has focused on the Th17 and Th1 phenotypes and on their pathogenic role in juvenile idiopathic arthritis, investigating how the cytokines produced by T helper cells act on resident cells on the synovia and which signal transduction pathways regulate Th17 cells proliferation and plasticity. In this context, an important milestone was represented by the identification of the non-classic Th1 phenotype, developed from the shift of Th17 cells. The cytokine TNF-α, beyond its well-known proinflammatory activity is involved in this process and this is one of the reasons why the TNF-α inhibitors are widely used in the treatment of juvenile idiopathic arthritis patients
CXCR3 and α<sub>E</sub>β<sub>7</sub> integrin identify a subset of CD8+ mature thymocytes that share phenotypic and functional properties with CD8+ gut intraepithelial lymphocytes
Background: We previously demonstrated the existence of two distinct subsets of T cell receptor (TCR)αβ+CD8αβ+ single positive (SP) cells in human postnatal thymus which express the chemokine receptor CCR7 or CXCR3 and migrate in vitro in response to their specific ligands.
Aim: To investigate whether these two CD8+ thymocyte subsets had distinct peripheral colonisation.
Methods: TCRαβ+CD8+ SP cells were obtained from normal postnatal thymus, mesenteric lymph node (LNs), small bowel, and peripheral blood (PB) specimens. Cells were then evaluated for expression of surface molecules, cytolytic potential, telomere length, and profile of cytokine production.
Results: CD8+CCR7+CXCR3− thymocytes exhibited CD62L, in common with those which localise to LNs. In contrast, CD8+CCR7−CXCR3+ thymocytes lacked CD62L but exhibited CD103, similar to intraepithelial lymphocytes (IELs) present in the gut mucosa where the CXCR3 ligand, CXCL10, and the CD103 ligand, E-cadherin, are highly and consistently expressed. In addition, thymocytes and gut CD8+CXCR3+CD103+ cells showed comparable telomere length, which was higher than that of PB CXCR3+CD8+ T cells. However, both of these populations contained perforin and granzyme A, and displayed the ability to produce interferon γ and interleukin 2. Of note, CXCR3 deficient, in comparison with wild-type C57Black/6, mice showed decreased proportions of CD3+CD8αβ+ and increased proportions of CD3+CD8αα+ lymphocytes at gut level. Moreover, adoptive transfer of CD3+CD8αβ+ thymocytes from wild-type into CXCR3 deficient mice resulted in a significant increase in CD3+CD8αβ+ T cells in the gut mucosa but not in other tissues.
Conclusions: The results of this study demonstrate the existence of a previously unrecognised subset of TCRαβ+CD8αβ+ SP CXCR3+CD103+ thymocytes which share phenotypic and functional features with CD8+ IELs, thus suggesting the possibility of their direct colonisation of the gut mucosa
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