University of Vienna

About: University of Vienna is a education organization based out in Vienna, Austria. It is known for research contribution in the topics: Population & Context (language use). The organization has 44686 authors who have published 95840 publications receiving 2907492 citations.

Accurate bulk properties from approximate many-body techniques.

Abstract: For ab initio electronic structure calculations, the random-phase approximation to the correlation energy is supposed to be a suitable complement to the exact exchange energy. We show that lattice constants, atomization energies of solids, and adsorption energies on metal surfaces evaluated using this approximation are in very good agreement with experiment. Since the method is fairly efficient and handles ionic, metallic, and van der Waals bonded systems equally well, it is a very promising choice to improve upon density functional theory calculations, without resorting to more demanding diffusion Monte Carlo or quantum chemical methods.

Activation, differential localization, and regulation of the stress-activated protein kinases, extracellular signal-regulated kinase, c-JUN N-terminal kinase, and p38 mitogen-activated protein kinase, in synovial tissue and cells in rheumatoid arthritis.

Abstract: Objective To investigate whether stress- and mitogen-activated protein kinases (SAPK/MAPK), such as extracellular signal–regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 MAPK, are significantly activated in rheumatoid arthritis (RA) synovial tissue compared with their activation in degenerative joint disease; to assess the localization of SAPK/MAPK activation in rheumatoid synovial tissue; and to search for the factors leading to stress kinase activation in human synovial cells. Methods Immunoblotting and immunohistology by antibodies specific for the activated forms of SAPK/MAPK were performed on synovial tissue samples from patients with RA and osteoarthritis (OA). In addition, untreated and cytokine-treated human synovial cells were assessed for SAPK/MAPK activation and downstream signaling by various techniques. Results ERK, JNK, and p38 MAPK activation were almost exclusively found in synovial tissue from RA, but not OA, patients. ERK activation was localized around synovial microvessels, JNK activation was localized around and within mononuclear cell infiltrates, and p38 MAPK activation was observed in the synovial lining layer and in synovial endothelial cells. Tumor necrosis factor α, interleukin-1 (IL-1), and IL-6 were the major inducers of ERK, JNK, and p38 MAPK activation in cultured human synovial cells. Conclusion Signaling through SAPK/MAPK pathways is a typical feature of chronic synovitis in RA, but not in degenerative joint disease. SAPK/MAPK signaling is found at distinct sites in the synovial tissue, is induced by proinflammatory cytokines, and could lead to the design of highly targeted therapies.

On a new Segal algebra

Abstract: By means of a certain kind of ‘atomic’ representation a new Segal algebraS0(G) of continuous functions on an arbitrary locally compact abelian groupG is defined. From various characterizations ofS0(G), e. g. as smallest element within the family of all strongly character invariant Segal algebras, functorial properties of the symbolS0 are derived, which are similar to those of the spacel (G) of Schwartz-Bruhat functions, e. g. invariance under the Fourier transform, or compatibility with restrictions to closed subgroups. The corresponding properties of its Banach dualS'0(G) as well as some of their applications are to be given in a subsequent paper.

Self-Recognition of Cd1 by γ/δ T Cells Implications for Innate Immunity

Abstract: The specificity of immunoglobulins and α/β T cell receptors (TCRs) provides a framework for the molecular basis of antigen recognition. Yet, evolution has preserved a separate lineage of γ/δ antigen receptors that share characteristics of both immunoglobulins and α/β TCRs but whose antigens remain poorly understood. We now show that T cells of the major tissue γ/δ T cell subset recognize nonpolymorphic CD1c molecules. These T cells proliferated in response to CD1+ presenter cells, lysed CD1c+ targets, and released T helper type 1 (Th1) cytokines. The CD1c-reactive γ/δ T cells were cytotoxic and used both perforin- and Fas-mediated cytotoxicity. Moreover, they produced granulysin, an important antimicrobial protein. Recognition of CD1c was TCR mediated, as recognition was transferred by transfection of the γ/δ TCR. Importantly, all CD1c-reactive γ/δ T cells express Vδ1 TCRs, the TCR expressed by most tissue γ/δ T cells. Recognition by this tissue pool of γ/δ T cells provides the human immune system with the capacity to respond rapidly to nonpolymorphic molecules on professional antigen presenting cells (APCs) in the absence of foreign antigens that may activate or eliminate the APCs. The presence of bactericidal granulysin suggests these cells may directly mediate host defense even before foreign antigen-specific T cells have differentiated.