44 research outputs found
Avian Bornaviruses Escape Recognition by the Innate Immune System
Like other pathogens that readily persist in animal hosts, members of the Bornaviridae family have evolved effective mechanisms to evade the innate immune response. The prototype of this virus family, Borna disease virus employs an unusual replication strategy that removes the triphosphates from the 5′ termini of the viral RNA genome. This strategy allows the virus to avoid activation of RIG-I and other innate immune response receptors in infected cells. Here we determined whether the newly discovered avian bornaviruses (ABV) might use a similar strategy to evade the interferon response. We found that de novo infection of QM7 and CEC32 quail cells with two different ABV strains was efficiently inhibited by exogenous chicken IFN-α. IFN-α also reduced the viral load in QM7 and CEC32 cells persistently infected with both ABV strains, suggesting that ABV is highly sensitive to type I IFN. Although quail cells persistently infected with ABV contained high levels of viral RNA, the supernatants of infected cultures did not contain detectable levels of biologically active type I IFN. RNA from cells infected with ABV failed to induce IFN-β synthesis if transfected into human cells. Furthermore, genomic RNA of ABV was susceptible to 5′-monophosphate-specific RNase, suggesting that it lacks 5′-triphospates like BDV. These results indicate that bornaviruses of mammals and birds use similar strategies to evade the host immune response
Recommended from our members
Chip-based duplex real-time PCR for water quality monitoring concerning Legionella pneumophila and Legionella spp.
Based on biomolecular methods, rapid and selective identification of human pathogenic water organisms becomes an important issue. Legionella spp., are pathogenic water bacteria with worldwide significance. Prevalent detection methods for these microorganisms are time and/or cost intensive. We describe a detection setup and relating DNA assay. A miniaturized real-time polymerase chain reaction (real-time PCR) for direct on-line discrimination of Legionella pneumophila and Legionella spp. was established and integrated into a real-time PCR-chip-system. The PCR-chip device combines a temperature controlling unit and a fluorescence intensity measurement. It was designed to achieve rapid amplification, using an approach of real-time fluorescence read out with the intercalating dye EvaGreen® and melting curve analysis, without requiring multiple probes. The presented results exhibit reproducibility and good sensitivity, showing that the setup is suitable for robust, rapid and cost-efficient detection and monitoring of a variety of Legionella spp.in urban water samples
Can Landform Stratification Improve our Understanding of Crop Yield Variability?
Farmers account for yield and soil variability to optimize their production under mainly economic considerations using the technology of precision farming. Therefore, understanding of the spatial variation of crop yield and crop yield development within arable fields is important for spatially variable management. Our aim was to classify landform units based on a digital elevation model, and to identify their impact on biomass development. Yield components were measured by harvesting spring barley (Hordeum vulgare, L.) in 1999, and winter rye (Secale cereale, L.) in 2000 and 2001, respectively, at 192 sampling points in a field in Saxony, Germany. The field was stratified into four landform units, i.e., shoulder, backslope, footslope and level. At each landform unit, a characteristic yield development could be observed. Spring barley grain yields were highest at the level positions with 6.7 t ha-1 and approximately 0.15 t ha-1 below that at shoulder and footslope positions in 1999. In 2000, winter rye harvest exhibited a reduction at backslope positions of around 0.2 t ha-1 as compared to the highest yield obtained again at level positions with 11.1 t ha-1. The distribution of winter rye grain yield across the different landforms was completely different in 2001 from that observed in 2000. Winter rye showed the highest yields at shoulder positions with 11.1 t ha-1, followed by the level position with 0.5 t ha-1 less grain yield. Different developments throughout the years were assumed to be due to soil water and meteorological conditions, as well as management history. Generally, crop yield differences of up to 0.7 t ha-1 were found between landform elements with appropriate consideration of the respective seasonal weather conditions. Landform analysis proved to be helpful in explaining variation in grain yield within the field between different years.JRC.H.6-Spatial data infrastructure
Activation of Type I and III Interferon Response by Mitochondrial and Peroxisomal MAVS and Inhibition by Hepatitis C Virus.
Sensing viruses by pattern recognition receptors (PRR) triggers the innate immune system of the host cell and activates immune signaling cascades such as the RIG-I/IRF3 pathway. Mitochondrial antiviral-signaling protein (MAVS, also known as IPS-1, Cardif, and VISA) is the crucial adaptor protein of this pathway localized on mitochondria, peroxisomes and mitochondria-associated membranes of the endoplasmic reticulum. Activation of MAVS leads to the production of type I and type III interferons (IFN) as well as IFN stimulated genes (ISGs). To refine the role of MAVS subcellular localization for the induction of type I and III IFN responses in hepatocytes and its counteraction by the hepatitis C virus (HCV), we generated various functional and genetic knock-out cell systems that were reconstituted to express mitochondrial (mito) or peroxisomal (pex) MAVS, exclusively. Upon infection with diverse RNA viruses we found that cells exclusively expressing pexMAVS mounted sustained expression of type I and III IFNs to levels comparable to cells exclusively expressing mitoMAVS. To determine whether viral counteraction of MAVS is affected by its subcellular localization we employed infection of cells with HCV, a major causative agent of chronic liver disease with a high propensity to establish persistence. This virus efficiently cleaves MAVS via a viral protease residing in its nonstructural protein 3 (NS3) and this strategy is thought to contribute to the high persistence of this virus. We found that both mito- and pexMAVS were efficiently cleaved by NS3 and this cleavage was required to suppress activation of the IFN response. Taken together, our findings indicate comparable activation of the IFN response by pex- and mitoMAVS in hepatocytes and efficient counteraction of both MAVS species by the HCV NS3 protease
Umgang mit Spannungen und Krisen in der therapeutischen Beziehung: Erste Erfahrungen mit einem handlungsorientierten Ausbildungs- und Supervisionskonzept
Aims: Alliance Focused Training (AFT) 1 aims at enhancing therapists' competences in resolving ruptures in the therapeutic alliance using video recordings and role-plays. This pilot study funded by the Heigl Foundation aimed at presenting initial results and clinical experiences with AFT in Germany, and to prepare a subsequent RCT.
Methods: 7 trainee therapists participated. Therapies of 15 patients with depressive disorder were analyzed.
Results and Conclusion: Trainees experienced AFT as very helpful for their professional development and for dealing with alliance ruptures. The therapeutic competence significantly improved both in self and in observer ratings. The results indicate that AFT is a promising approach to improve psychotherapy training, emphasizing the relevance of the planned proof of concept RCT
Development and validation of novel AAV2 random libraries displaying peptides of diverse lengths and at diverse capsid positions
Cardiac Liposarcoma-A Review of Outcome after Surgical Resection
Objective This review was performed to pool the current surgical strategies for cardiac liposarcoma. Methods A literature search was performed and all studies published in full-text or abstract forms were eligible for inclusion without applying any language restrictions. Case reports without surgical intervention, reporting noncardiac liposarcoma, animal cases, or review articles were excluded after initial abstract review. Analyzed postoperative outcomes included intraoperative and in-hospital mortality, longest reported survival, and recrudescence. Results After a critical evaluation 53 unique surgically treated case reports published between the years 1966 and December 2012 were included in this review. Most of the reported cardiac liposarcoma are myxoid (49.1%), pleomorphic liposarcoma occur with a prevalence of 20.8%, and well-differentiated tumors are observed in 13.2%. One-year survival rate increases the more differentiated the tumor is categorized: 54.5% for pleomorphic, 65.4% for myxoid, and 100% for well-differentiated liposarcoma (p = 0.096). Conclusion Total surgical resection of cardiac liposarcoma is the only curative option, as it tends to local and distant recurrence. Therefore, a frequent follow-up examination should be considered
Subcellular localization of endogenous and engineered MAVS variants.
<p>(A) Subcellular localization of MAVS in Huh7 cells was determined by immunofluorescence. White arrows indicate co-localization of MAVS (green) with the peroxisomal marker PMP70 (purple). Mitochondria were stained with mitotracker (red) while nuclei were stained with DAPI. Scale bar, 10 μm. (B) Quantification of subcellular localization of MAVS on mitochondria and peroxisomes as determined with the Mander’s overlap coefficient. In addition, co-localization of peroxisomes with mitochondria was determined. Bars indicate the standard error. *, P≤0.05. (C) Organelle-targeted MAVS<sup>CR</sup> (i.e. MAVS that is NS3/4A protease cleavage resistant) constructs were designed by replacing the transmembrane (TM)-domain (light grey) of wild type (wt) MAVS with either the TM-domain of <i>Pex13</i> (pexMAVS) or <i>Bcl-Xl</i> (mitoMAVS). The HCV NS3/4A cleavage site was mutated to obtain a cleavage resistant (CR) MAVS protein (C508R). The MAVS coding sequence is indicated in light blue and includes the CARD as well as the proline-rich sequence (grey boxes). (D) Co-localization of MAVS variants with given marker proteins (red) was determined in Huh7-NS3/4A expressing cells transduced with wt-, pex- or mitoMAVS<sup>CR</sup>-HA (green) by using immunofluorescence. Scale bar, 20 μm. (E) The degree of co-localization was quantified by calculating the Mander’s overlap coefficient. Each dot represents a single cell; at least 20 cells were analyzed per condition.</p