Single-cell RNA-sequencing of herpes simplex virus 1-infected cells connects NRF2 activation to an antiviral program

Herpesvirus infection initiates a range of perturbations in the host cell, which remain poorly understood at the level of individual cells. Here, we quantify the transcriptome of single human primary fibroblasts during the first hours of lytic infection with HSV-1. By applying a generalizable analysis scheme, we define a precise temporal order of early viral gene expression and propose a set-wise emergence of viral genes. We identify host cell genes and pathways relevant for infection by combining three different computational approaches: gene and pathway overdispersion analysis, prediction of cell-state transition probabilities, as well as future cell states. One transcriptional program, which correlates with increased resistance to infection, implicates the transcription factor NRF2. Consequently, Bardoxolone methyl and Sulforaphane, two known NRF2 agonists, impair virus production, suggesting that NRF2 activation restricts viral infection. Our study provides insights into early stages of HSV-1 infection and serves as a general blueprint for the investigation of heterogeneous cell states in virus infection.

Analytical pair correlations in ideal quantum gases: temperature-dependent bunching and antibunching

The fluctuation-dissipation theorem together with the exact density response spectrum for ideal quantum gases has been utilized to yield a new expression for the static structure factor, which we use to derive exact analytical expressions for the temperature-dependent pair distribution function g(r) of the ideal gases. The plots of bosonic and fermionic g(r) display "Bose pile" and "Fermi hole" typically akin to bunching and antibunching as observed experimentally for ultracold atomic gases. The behavior of spin-scaled pair correlation for fermions is almost featureless, but bosons show a rich structure including long-range correlations near T(c). The coherent state at T=0 shows no correlation at all, just like single-mode lasers. The depicted decreasing trend in correlation with decrease in temperature for T<T(c) should be observable in accurate experiments.

Dielectric and transport properties of a supercooled symmetrical molten salt

The liquid-glass transition of the restricted primitive model for a symmetrical molten salt is studied using mode-coupling theory. The transition at high densities is predicted to obey the Lindemann criterion for melting, and the charge-density peak found in neutron-scattering experiments on ionic glass formers is qualitatively reproduced. Frequency-dependent dielectric functions, shear viscosities, and dynamical conductivities of the supercooled liquid are presented. Comparing the latter to the diffusion constant, we find that mode-coupling theory reproduces the Nernst-Einstein relation. The Stokes-Einstein radius is found to be approximately equal to the particle radius only near the high-density glass transition.

Development and validation of an indirect enzyme immunoassay for detection of antibody to Brucella abortus in milk

An indirect enzyme immunoassay for detection of antibody to Brucella abortus in bovine milk was developed and validated using 6238 milk samples from Canadian herds (brucellosis free) and 202 samples from herds infected with B. abortus (from Argentina and Chile). The assay utilized lipopolysaccharide as the antigen, immobilized on the polystyrene matrix, whole milk to test and a mouse monoclonal antibody, specific for an epitope of bovine IgG1, conjugated with horseradish peroxidase. The sensitivity of the assay was 95.2% +/- 3.7% at a confidence limit of 95% for samples from B. abortus infected herds obtained from chile and 98.7% +/- 0.3% at a confidence limit of 95% for samples from similar herds in Argentina. Of the negative milk samples tested, 77 gave a result above the threshold value of 0.200 optical density units. When the 77 false positive samples were retested using 7.5 mM (final concentration) of EDTA and ethyleneglycol-bis-aminoether-N,N,N', N'-tetraacetic acid (EGTA), the number of false positive reactions was reduced to 3, giving a diagnostic specificity of 99.95%. The divalent cation chelating agents did not affect positive reactions and the sensitivity remained the same. Based on control samples included with each assay, the performance of the assay was consistent.

The use of divalent cation chelating agents (EDTA/EGTA) to reduce non-specific serum protein interaction in enzyme immunoassay

An indirect enzyme immunoassay (ELISA) for detection of bovine antibody to Brucella abortus was modified by the addition of divalent chelating agents to the serum diluent. This addition resulted in an increase in specificity from 96.0% in the regular assay to 99.4% in the modified procedure. Of the 15,715 sera initially tested by the indirect ELISA, 691 that had given positive reactions were selected for retesting in the indirect ELISA with EDTA/EGTA added. The buffered plate antigen test (BPAT) correctly identified 98.6% of the samples as negative. The addition of chelating agents did not alter the sensitivity of the indirect ELISA, which correctly classified 609 sera from animals from which B. abortus had been isolated as positive. The sensitivity of the BPAT was 97.8%.