University of Zurich

About: University of Zurich is a education organization based out in Zurich, Switzerland. It is known for research contribution in the topics: Population & Medicine. The organization has 50842 authors who have published 124042 publications receiving 5304521 citations. The organization is also known as: UZH & Uni Zurich.

Nuclear Activity of MLA Immune Receptors Links Isolate-Specific and Basal Disease-Resistance Responses

Abstract: Plant immune responses are triggered by pattern recognition receptors that detect conserved pathogen-associated molecular patterns (PAMPs) or by resistance (R) proteins recognizing isolate-specific pathogen effectors. We show that in barley, intracellular mildew A (MLA) R proteins function in the nucleus to confer resistance against the powdery mildew fungus. Recognition of the fungal avirulence A10 effector by MLA10 induces nuclear associations between receptor and WRKY transcription factors. The identified WRKY proteins act as repressors of PAMP-triggered basal defense. MLA appears to interfere with the WRKY repressor function, thereby de-repressing PAMP-triggered basal defense. Our findings reveal a mechanism by which these polymorphic immune receptors integrate distinct pathogen signals.

On the cellular source and function of interleukin 6 produced in the central nervous system in viral diseases.

Abstract: Interleukin 6 (IL 6) was found to be produced in the central nervous system (CNS) of ICR +/+ mice infected with lymphocytic choriomeningitis virus (LCMV) or with vesicular stomatitis virus (VSV). When infecting athymic ICR nu/nu mice which cannot develop T cell-mediated meningitis after LCMV infection, no significant synthesis of IL 6 was detected in the CNS. IL 6 was found, however, to be produced intrathecally in ICR nu/nu mice infected with VSV, which causes a T cell-independent acute encephalitis. This suggested that IL 6 may also originate from cells not belonging to the T cell compartment. Indeed, in vitro assays showed that both virus-infected microglial cells and astrocytes secreted IL 6. In astrocytes, the infection resulted in the induction of the 1.3-kb messenger RNA IL 6. Besides its effect on the development of B cell immunity in the brain, IL 6 may be involved in repair mechanisms initiated in the course of viral-induced tissue damage. As shown here, IL 6 induced an increase of the secretion of a neurotrophic factor, nerve growth factor by astrocytes. Thus, the intrathecal synthesis of IL 6 may be part of the host response to infection favoring immune-mediated elimination of the infectious agent as well as trophic support for neurons.

A systematic review of the survival and complication rates of implant-supported fixed dental prostheses (FDPs) after a mean observation period of at least 5 years.

Abstract: Objectives The objective of this systematic review was to assess the 5- and 10-year survival of implant-supported fixed dental prostheses (FDPs) and to describe the incidence of biological and technical complications. Methods An electronic Medline search complemented by manual searching was conducted to identify prospective and retrospective cohort studies and case series on FDPs with a mean follow-up time of at least 5 years. Patients had to have been examined clinically at the follow-up visit. Failure and complication rates were analyzed using standard and random-effects Poisson regression models to obtain summary estimates of 5-year and 10-year survival and complication rates. Results The updated search provided 979 titles and 257 abstracts. Full-text analysis was performed for 90 articles resulting in a total 32 studies that met the inclusion criteria. Meta-analysis of these studies indicated an estimated survival of implants supporting FDPs of 95.6% after 5 years and 93.1% after 10 years. When machined surface implants were excluded from the analysis and only rough surface implants included, the survival rate increased to 97.2% after 5 years. The survival rate of implant-supported FDPs was 95.4% after 5 years and 80.1% after 10 years of function. When the analysis was done exclusively for metal–ceramic FDPs, hence the old gold–acrylic FDPs were excluded, the survival rate increased significantly. The survival rate of metal–ceramic implant-supported FDPs was 96.4% after 5 years and 93.9% after 10 years. Only 66.4% of the patients were free of any complications after 5 years. The most frequent complications over the 5-year observation period were fractures of the veneering material (13.5%), peri-implantitis and soft tissue complications (8.5%), loss of access hole restoration (5.4%), abutment or screw loosening (5.3%), and loss of retention of cemented FDPs (4.7%). Conclusion It may be concluded that implant-supported fixed dental prostheses (FDPs) are a safe and predictable treatment method with high survival rates. However, biological and technical complications were frequent (33.6%). To minimize the incidence of complications, dental professionals should make great effort in choosing reliable components and materials for implant-supported FDPs and the patients should be placed in well-structured maintenance system after treatment.

ICOS is essential for effective T-helper-cell responses.

Abstract: The outcome of T-cell responses after T-cell encounter with specific antigens is modulated by co-stimulatory signals, which are required for both lymphocyte activation and development of adaptive immunity1,2,3. ICOS4,5, an inducible co-stimulator with homology to CD28, is expressed on activated, but not resting T cells, and shows T-cell co-stimulatory function in vitro. ICOS binds specifically to its counter-receptor B7RP-1 (refs 5,6,7), but not to B7-1 or B7-2. Here we provide in vivo genetic evidence that ICOS delivers a co-stimulatory signal that is essential both for efficient interaction between T and B cells and for normal antibody responses to T-cell-dependent antigens. To determine the physiological function of ICOS, we generated and characterized gene-targeted ICOS-deficient mice. In vivo, a lack of ICOS results in severely deficient T-cell-dependent B-cell responses. Germinal centre formation is impaired and immunoglobulin class switching, including production of allergy-mediating IgE, is defective. ICOS-deficient T cells primed in in vivo and restimulated in vitro with specific antigen produce only low levels of interleukin-4, but remain fully competent to produce interferon-γ.