NeuroReport 22:865-869 (C) 2011 Wolters Kluwer Health vertical bar Lippincott Williams
“Alphaviruses, such as chikungunya virus, o’nyong-nyong virus, and Ross River virus (RRV), cause outbreaks of human rheumatic disease worldwide. RRV is a positive-sense single-stranded RNA virus endemic to Australia and Papua New Guinea. In this study, we sought to this website establish an in vitro model of RRV evolution in response to cellular antiviral defense mechanisms. RRV was able to establish persistent infection in activated macrophages, and a small-plaque variant (RRV(PERS)) was isolated after several weeks of culture. Nucleotide sequence analysis of RRV(PERS) found several nucleotide differences in the nonstructural protein (nsP) region PCI32765 of the RRV(PERS) genome. A point mutation was also detected in the E2 gene. Compared to the parent virus (RRV-T48), RRV(PERS) showed significantly enhanced resistance to beta interferon (IFN-beta)-stimulated antiviral activity. RRV(PERS) infection of RAW 264.7 macrophages induced lower levels of IFN-beta expression and production than infection with RRV-T48. RRV(PERS) was also able to inhibit type I IFN signaling. Mice infected with RRV(PERS) exhibited significantly enhanced disease severity and mortality compared to mice infected with RRV-T48. These results provide strong evidence that
the cellular antiviral
response can direct selective pressure for viral sequence evolution that impacts on virus fitness and sensitivity to alpha/beta IFN (IFN-alpha/beta).”
“A prominent theory of the N2 event-related SCH772984 order potential component holds that the ‘oddball’ N2 is generated in the anterior cingulate cortex. However, observations of oddball N2s with posterior scalp distributions are inconsistent with this hypothesis. We suggest that variability in the topology of the oddball N2 is a key characteristic of the component that can inform theories of its neural basis. We propose that the oddball N2 reflects cortex-wide noradrenergic modulation of the ongoing cortical activity and thus should have a topology that varies systematically according to task specifics. Participants engaged in an oddball task with male and female faces tinted either yellow or blue, counting targets according to color or sex. Between blocks, targets were frequent or infrequent, counterbalanced across task (attend color, attend sex), and category (blue male, yellow male, blue female, yellow female). We created difference waves by subtracting frequent from infrequent category trials to isolate the oddball N2. When participants attended to color the oddball N2 was maximal over frontal-central areas and when they attended to sex it was maximal over lateral-occipital areas.