The infectivity of fixed rabies virus in a number of cell lines has been shown to be markedly enhanced by the addition of protamine or diethylaminoethyl dextran to the virus inoculum. The polycations appear to exert their influence at a very early stage (adsorption or penetration or both) of virus-cell interaction. Immune globulin blocked infection completely when added up to 5 min after exposu...

Sambucus nigra (elder) are broadly used species to treat microbial infections. The potential antiviral activity and mechanism action of elder fruit (EF) in human epithelium cell (A549) cultures infected with H9N2 influenza virus were determined. The effect of various concentrations of EF on influenza virus replication was examined by using virus titration, quantitative real time RT-PCR, fusion ...

In titrating serum immunoglobulin G antibody to viruses by enzyme-linked immunosorbent assay, we used two rows of wells for serial twofold dilutions of the serum; in one row, a low concentration of a protein denaturant, 0.5 or 1.0 M guanidine hydrochloride, was added to the diluent so that the binding of low-avidity antibodies to viral antigens on the solid phase was inhibited. We then compared...

Thymidine-sparing triple-nucleoside regimens have exhibited poor virologic response despite apparent phenotypic susceptibility to 2 of 3 regimen components at early time points. Phenotypic resistance masking by wild-type virus may explain this discrepancy.Consistent with this notion were (1) the presence of low level nucleoside reverse-transcriptase inhibitor-resistant human immunodeficiency vi...

The colony formation assay is the most commonly used titration method for defining the concentration of replication-incompetent murine leukemia virus-derived retroviral vectors. However, titer varies with target cell type and number, transduction time, and concentration of polycation (e.g., Polybrene). Moreover, because most of the viruses cannot encounter target cells due to Brownian motion, t...

Objectives of vaccination always place priority on the protection of human beings from rabies by vaccinating either the vector species (the fox in most countries), the relay species (domestic animals)or human beings themsel­ ves. Other objectives of vaccination are to reduce economic loss or to avoid creating a secondary cycle of rabies among domestic animals. Vaccines containing live virus (Fl...

We have recently found that DNA packaged in phage λ undergoes a disordering transition triggered by temperature, which results in increased genome mobility. This solid-to-fluid like DNA transition markedly increases the number of infectious λ particles facilitating infection. However, the structural transition strongly depends on temperature and ionic conditions in the surrounding medium. Using...

Young mice fed diets deficient in pyridoxine or fed desoxypyridoxine after the inoculation of the pneumonia virus of mice were more resistant to infection than well nourished controls. The susceptibility of young mice to PVM increased with the duration of pyridoxine administration after inoculation. Dietary protein restriction when pyridoxine was provided did not affect the susceptibility of mi...