Search results for "Unity"
showing 10 items of 3852 documents
The IFN-γ-Inducible GTPase, Irga6, Protects Mice against Toxoplasma gondii but Not against Plasmodium berghei and Some Other Intracellular Pathogens
2011
Clearance of infection with intracellular pathogens in mice involves interferon-regulated GTPases of the IRG protein family. Experiments with mice genetically deficient in members of this family such as Irgm1(LRG-47), Irgm3(IGTP), and Irgd(IRG-47) has revealed a critical role in microbial clearance, especially for Toxoplasma gondii. The in vivo role of another member of this family, Irga6 (IIGP, IIGP1) has been studied in less detail. We investigated the susceptibility of two independently generated mouse strains deficient in Irga6 to in vivo infection with T. gondii, Mycobacterium tuberculosis, Leishmania mexicana, L. major, Listeria monocytogenes, Anaplasma phagocytophilum and Plasmodium …
On Participating in Communities of Practice
2004
This chapter examines the social practices of three classroom communities where pedagogy in the learning of science draws on the socio-cultural perspective. The pedagogical framework for science education, defined in this study as a participatory approach, views learning as a collective process of meaning-making situated in cultural contexts (e.g. Cole, 1996; Sfard, 1998; Wells; 1999). There are three focuses of interest, namely, the nature of role negotiation between the members of the learning community, the application of cultural tools in collective activity, and the processes of making meaning for a scientific phenomenon. The social practices of the science classroom communities are ap…
IL-10 Controls Ultraviolet-Induced Carcinogenesis in Mice
2007
Abstract UV radiation-induced immunosuppression contributes significantly to the development of UV-induced skin cancer by inhibiting protective immune responses. IL-10 has been shown to be a key mediator of UV-induced immunosuppression. To investigate the role of IL-10 during photocarcinogenesis, groups of IL-10+/+, IL-10+/−, and IL-10−/− mice were chronically irradiated with UV. IL-10+/+ and IL-10+/− mice developed skin cancer to similar extents, whereas IL-10−/− mice were protected against the induction of skin malignancies by UV. Because UV is able to induce regulatory T cells, which play a role in the suppression of protective immunity, UV-induced regulatory T cell function was analyzed…
Autoantibodies in complex regional pain syndrome bind to a differentiation-dependent neuronal surface autoantigen.
2009
Complex regional pain syndrome, which is characterised by pain and trophic disturbances, develops frequently after peripheral limb trauma. There is an increasing evidence of an involvement of the immune system in CRPS, and recently we showed that CRPS patients have autoantibodies against nervous system structures. Therefore we tested the sera of CRPS patients, neuropathy patients and healthy volunteers for surface-binding autoantibodies to primary cultures of autonomic neurons and differentiated neuroblastoma cell lines using flow cytometry. Thirteen of 30 CRPS patients, but none of 30 healthy controls and only one of the 20 neuropathy sera had specific surface binding to autonomic neurons …
Neurons as targets for T cells in the nervous system
2013
International audience; Accumulating evidence shows that T cells penetrate the central nervous system (CNS) parenchyma in several autoimmune, infectious, and degenerative neurological diseases. The structural and functional consequences for CNS neurons of their encounter with activated T cells have been investigated in several experimental systems, including ex vivo co-cultures, electrophysiology, and in vivo imaging. Here, we review the modalities of neuron/T cell interactions. We substantiate the contention that T cells are directly responsible for neuronal damage in a large number of neurological diseases and discuss mechanisms of neuronal damage mediated by distinct T cell subsets, the …
What Could Be a Primary Cause of Multiple Sclerosis: Is It an Autoimmunity Triggered by Chronic Protozoan Infection?
2013
The generally accepted paradigm of multiple sclerosis is the autoimmune one; still, a body of evidence suggests that this disease may actually be triggered by an infectious factor. In this paper, it is hypothesized that multiple sclerosis may actually be a rare complication of a protozoan infection, which is usually asymptomatic but in some susceptible individuals is accompanied by autoimmune attack against the nervous tissue. If multiple sclerosis were actually caused by such an infection, then a microorganism responsible should exhibit several properties: it (i) is transmitted by an arthropod vector; (ii) is characterized by specific metabolism of the lipids; (iii) should be dependent on …
The origin of strong ties: The role of weak ties in the emergence and evolution of alliance networks
2017
Interorganizational ties are distinguished into strong and weak on the basis of their strength. By focusing mainly on strong alliances ties, previous research has fallen short to explain the role of weak ties among organizations for the evolution of alliance networks. With the aim of scrutinizing the role of weak ties in the establishment, maintaining, and transforming of alliance ties, we develop a conceptual framework that looks at networks of interorganizational weak ties as conduits for the dissemination of information about (valuable) knowledge sets that supports the processes of opportunity discovery and/or creation. The exploitation of the discovered or created opportunities leads to…
Imported Stem Cells Strike against Stroke.
2015
Cells with neural stem cell (NSC)-like properties can be isolated from the cortex of adult brains following injury, but their origins and function are unclear. Now in Cell Stem Cell, Faiz et al. (2015) show that subventricular-zone-derived NSCs home to injured cortical area following stroke, where they generate reactive astrocytes.
IL-17 promotes progression of cutaneous leishmaniasis in susceptible mice.
2009
Abstract Resistance to leishmaniasis in C57BL/6 mice depends on Th1/Tc1 cells. BALB/c mice preferentially develop Th2 immunity and succumb to infection. We now assessed the role of IL-17 in cutaneous leishmaniasis. During the course of Leishmania major infection, BALB/c CD4 cells and neutrophils produced increased amounts of IL-17 as compared with cells from C57BL/6 mice. This increase was associated with significantly increased IL-23 release from L. major-infected BALB/c dendritic cells (DC), whereas IL-6 and TGF-β1 production by BALB/c and C57BL/6 DC were comparable. Interestingly, lesion sizes in infected IL-17-deficient BALB/c mice were dramatically smaller and failed to progress as com…
Characterization of neutrophil subsets in healthy human pregnancies
2014
We have previously shown that in successful pregnancies increased arginase activity is a mechanism that contributes to the suppression of the maternal immune system. We identified the main type of arginase-expressing cells as a population of activated low-density granulocytes (LDGs) in peripheral blood mononuclear cells and in term placentae. In the present study, we analyzed the phenotype of LDGs and compared it to the phenotype of normal density granulocytes (NDGs) in maternal peripheral blood, placental biopsies and cord blood. Our data reveal that only LDGs but no NDGs could be detected in placental biopsies. Phenotypically, NDGs and LDGs from both maternal and cord blood expressed diff…