Search results for " tolerance"
showing 10 items of 760 documents
Modeling temperature effects on mortality: multiple segmented relationships with common break points.
2008
We present a model for estimation of temperature effects on mortality that is able to capture jointly the typical features of every temperature-death relationship, that is, nonlinearity and delayed effect of cold and heat over a few days. Using a segmented approximation along with a doubly penalized spline-based distributed lag parameterization, estimates and relevant standard errors of the cold- and heat-related risks and the heat tolerance are provided. The model is applied to data from Milano, Italy.
Modified Devine Exclusion for Unresectable Distal Gastric Cancer in Symptomatic Patients
2017
<b><i>Background:</i></b> In patients with outlet obstruction syndrome and/or severe anemia secondary to unresectable gastric cancer (GC), partial stomach-partitioning gastrojejunostomy, or modified Devine exclusion, is a surgical alternative. <b><i>Methods:</i></b> A retrospective study was conducted on patients with unresectable distal GC treated with modified Devine exclusion as palliative surgery between February 2005 and December 2015. It consisted of a series of 10 patients with outlet obstruction syndrome and/or severe anemia. The outcomes of this technique were based on oral tolerance, blood transfusions, postoperative complications, a…
Drought tolerance of clonal Malus determined from measurements of stomatal conductance and leaf water potential.
2003
We examined tolerance to soil drying in clonally propagated apple (Malus domestica Borkh.) rootstocks used to control shoot growth of grafted scions. We measured leaf conductance to water vapor (g(L)) and leaf water potential (Psi(L)) in a range of potted, greenhouse-grown rootstocks (M9, M26, M27, MM111, AR69-7, AR295-6, AR360-19, AR486-1 and AR628-2) as the water supply was gradually reduced. Irrespective of the amount of available water, rootstocks that promoted scion shoot growth (M26 and MM111) generally had higher g(L) and more negative Psi(L) than rootstocks that restricted scion shoot growth (M27 and M9). After about 37 days of reduced water supply, there were significant decreases …
Stress tolerance and ABA signaling through PYR/PYL receptors and PP2Cs in tomato
2013
Lifelong exposure to low dose xeno-hormones in rats : multi-generational effects of xeno-hormone mixtures on taste preferences, maternal behavior, an…
2012
During the last decade, the issue of health-related endocrine disruptors (ED) has been extended to the toxicity of mixtures. The objective of this study was to define the effects of lifelong exposure to ED mixtures, at low doses defined as "non-harmful" by the authorities. In this aim, the effects of mixtures combining genistein, vinclozolin and bisphenol A, have been investigated in the rat by using an integrative and multi-generational experimental approach which takes into account maternal behavior, feeding behavior and development. Our results show that these mixtures could: a) reduce maternal behavior, b) change taste preferences (sweet, salty), c) affect the development from the in ut…
Immature, but not inactive: the tolerogenic function of immature dendritic cells.
2002
The induction of antigen-specific T cell tolerance and its maintenance in the periphery is critical for the prevention of autoimmunity. Recent evidence shows that dendritic cells (DC) not only initiate T cell responses, but are also involved in silencing of T cell immune responses. The functional activities of DC are mainly dependent on their state of activation and differentiation, that is, terminally differentiated mature DC can efficiently induce the development of T effector cells, whereas immature DC are involved in maintenance of peripheral tolerance. The means by which immature DC maintain peripheral tolerance are not entirely clear, however, their functions include the induction of …
Beta-Catenin mediates tumor-induced immunosuppression by inhibiting cross-priming of CD8(+) T cells
2014
Tumors activate -catenin in DCs to suppress CD8 immunity by inhibiting cross-priming; -catenin-suppressed CD8 immunity could be rescued by enhancing cross-priming. Whereas CD8(+) T cells are essential for anti-tumor immunity, tumors often evade CD8(+) T cell surveillance by immunosuppression. As the initiators of antigen-specific immune responses, DCs are likely to play a central role in regulating the balance between immunity and tolerance to tumor antigens and are specialized in their ability to cross-present exogenous tumor antigens on MHC class I molecules to initiate CD8(+) T cell immunity. However, it remains unclear whether and how tumors modulate DC functions to suppress CD8(+) T ce…
CD4 blockade directly inhibits mouse and human CD4+ T cell functions independent of Foxp3+ Tregs
2013
CD4(+) helper T cells orchestrate protective immunity against pathogens, yet can also induce undesired pathologies including allergies, transplant rejection and autoimmunity. Non-depleting CD4-specific antibodies such as clone YTS177.9 were found to promote long-lasting T cell tolerance in animal models. Thus, CD4 blockade could represent a promising therapeutic approach for human autoimmune diseases. However, the mechanisms underlying anti-CD4-induced tolerance are incompletely resolved. Particularly, multiple immune cells express CD4 including Foxp3(+) regulatory T cells (Tregs) and dendritic cells (DCs), both controlling the activation of CD4(+)Foxp3(-) helper T cells. Utilizing mixed le…
The mitochondrial protein TCAIM regulates activation of T cells and thereby promotes tolerance induction of allogeneic transplants.
2013
Primary T cell activation and effector cell differentiation is required for rejection of allogeneic grafts in naive recipients. It has become evident, that mitochondria play an important role for T cell activation. Expression of several mitochondrial proteins such as TCAIM (T cell activation inhibitor, mitochondrial) is down-regulated upon T cell receptor triggering. Here we report that TCAIM inhibited spontaneous development of memory and effector T cells. CD4(+) T cells from Tcaim knock-in (KI) mice showed reduced activation, cytokine secretion and proliferation in vitro. Tcaim KI T cells tolerated allogeneic skin grafts upon transfer into Rag-1 KO mice. CD4(+) and CD8(+) T cells from the…
Tonic T cell signalling and T cell tolerance as opposite effects of self-recognition on dendritic cells.
2010
Naive T cells spend most of their time scanning the surface of dendritic cells (DCs), indicating that self-MHC/T cell receptor (TCR) interactions between these immune cells occur routinely in peripheral organs during the steady state. Peripheral self-MHC recognition on DCs drives seemingly opposing effects in the absence of inflammatory stimuli such as deletion of certain self-reactive T cells as well as maintenance of the T cell responsiveness to antigen, both of which shape the T cell repertoire and regulate T cell responses. Here we review recent data on the role of self-MHC recognition on steady-state DCs in the periphery and propose that interactions between T cells and steady-state DC…