Concentrated HA-pseudotypes were further shown to work well in hemagglutination inhibition assays. Finally, antisera elicited by genetically modified HA, with changes in the polybasic cleavage site that have been used in some H5 vaccines and reduce pathogenicity, gave identical neutralization titers against HA-pseudotypes with wild type or modified HA. These findings support continued development of HA-pseudotypes as a robust tool for analyzing sera in vaccine and serologic studies. Published by Elsevier B.V.”
“Research on the temporal characteristics of visual processing, as measured with critical flicker fusion or the latency of visual evoked potential (VEP), shows
controversial results if different eccentricities of visual stimuli are compared. To clarify this question, a direct measure of cortical activity with magnetoencephalography (MEG) was applied this website to examine the neuronal summation latency and peak latency for both near and far peripheral stimuli. Consistent with cortical magnification, the peak amplitude for less eccentric stimuli was larger than that for more eccentric stimuli. More importantly, the
current data also demonstrated longer cortical summation latency and peak latency for more eccentric visual stimuli, but only the summation latency difference between near and far stimuli correlated with the peak amplitude difference between near and far stimuli. These results suggest dissociable mechanisms of summation latency and peak latency with respect to their contributions to the stimulus eccentricity effect, Selleck Fulvestrant and provide potential explanations for controversial results in previous studies. (C) 2010 Elsevier Ireland Ltd. All rights reserved.”
“The aim of this study was to compare sensitivity thresholds of two pre-screening methods – the heteroduplex mobility assay (HMA) and the presence of ambiguity codes in population-based sequences – applied for detection of HIV-1 superinfection. HIV-1 env C2-C4 PCR products generated from 48 serum samples isolated from 24 HIV-1 positive and therapy-nave homosexual men at seroconversion and at approximately 1 year thereafter were subjected to HMA and population sequencing. Clonal sequence analysis was
5-FU nmr used to determine the sensitivity of each method to detect sequence variability. Results from HMA were compared to pairwise genetic distance of clonal sequences; heteroduplexes resulted from as little as 1.4% pairwise distance between two sequences and were detected even when only 1.5% of the pairwise distance comparisons exceeded this distance threshold. By contrast, the ambiguity code approach using population-based sequencing detected only 20.1% of existing sequence variation and was less sensitive to minority populations <= 20%, resulting in an underestimation of HIV-1 diversity. Thus, HMA was found to be more sensitive for detection of sequence variations than the ambiguity code approach, suggesting that HMA would be a more appropriate method to pre-screen for HIV-1 superinfection.