182 resultados para deformed wing virus
Resumo:
Foot-and-mouth disease virus (FMDV), a member of the Picornaviridae, is a pathogen of cloven-hoofed animals and causes a disease of major economic importance. Picornavirus-infected cells show changes in cell morphology and rearrangement of cytoplasmic membranes, which are a consequence of virus replication. We show here, by confocal immunofluorescence and electron microscopy, that the changes in morphology of FMDV-infected cells involve changes in the distribution of microtubule and intermediate filament components during infection. Despite the continued presence of centrosomes in infected cells, there is a loss of tethering of microtubules to the microtubule organizing center (MTOC) region. Loss of labeling for -tubulin, but not pericentrin, from the MTOC suggests a targeting of -tubulin (or associated proteins) rather than a total breakdown in MTOC structure. The identity of the FMDV protein(s) responsible was determined by the expression of individual viral nonstructural proteins and their precursors in uninfected cells. We report that the only viral nonstructural protein able to reproduce the loss of -tubulin from the MTOC and the loss of integrity of the microtubule system is FMDV 3Cpro. In contrast, infection of cells with another picornavirus, bovine enterovirus, did not affect -tubulin distribution, and the microtubule network remained relatively unaffected.
Resumo:
The causes of Alzheimer's disease (AD) and of the characteristic pathological features—amyloid plaques and neurofibrillary tangles—of AD brain are unknown, despite the enormous resources provided over the years for their investigation. Indeed, the only generally accepted risk factors are age, Down syndrome, carriage of the type 4 allele of the apolipoprotein E gene (APOE-e 4), and possibly brain injury. Following the authors' previous studies implicating herpes simplex virus type 1 (HSV1) in brain of APOE-e 4 carriers as a major cause of AD, the authors propose here, on the basis of their and others' recent studies, that not only does HSV1 generate the main components of amyloid plaques and neurofibrillary tangles (NFTs)—ß -amyloid (Aß) and abnormally phosphorylated tau but also, by disrupting autophagy, it prevents degradation of these aberrant proteins, leading to their accumulation and deposition, and eventually to AD.
Resumo:
This research rests on the assumption that individual differences approaches to prejudice benefit from all integration of intergroup factors. Following Duckitt (2001), we assumed that two prominent individual differences variables, right-wing authoritarianism (RWA) and social dominance orientation (SDO), would differentially predict majority members' levels of ethnic prejudice depending on specific factors of the intergroup context: RWA as all index of motivational concerns about social cohesion, stability and security should drive prejudice against outgroups perceived as socially threatening, and SDO as an index of concerns about ingroup superiority and dominance should predict prejudice against outgroups perceived as potential competitors for power-status. Across two studies (Ns = 82, 176), using between-participants and within-participants experimental designs, the effects of RWA on prejudice were particularly powerful when the outgroup was manipulated to be socially threatening, but the effects of SDO on prejudice appeared not to increase when the outgroup was manipulated to be competitive. In Study 2, presenting the outgroup as having low status also increased the effect of RWA, but not the effect of SDO. These results support the differential prediction assumption for RWA, but not for SDO. Implications for the conceptualisation of RWA and SDO are discussed. Copyright (C) 2008 John Wiley & Sons, Ltd.