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F Righthand

Publications and source records attributed to F Righthand.

4 recordsLinked to original sources
PubMed1972

In vitro interactions between virus and enhancer.

Cell-free supernatant fluids of permissive host cells contained an enhancer for the m+ variant of echovirus 6. The enhancer activity remained in supernatant fractions after centrifugation at 110,000 x g for 4 hr. Under in vitro conditions, a complex between enhancer and virus formed rapidly. The complex was not dissociated by dilution and was sedimented by centrifugation. The effect of enhancer on the distribution of virus in CsCl density gradients was determined. In the absence of enhancer, virus was recovered in one peak at 1.33 g/ml. Incubation of enhancer with virus before centrifugation resulted in the formation of two peaks of infectivity at 1.33 g/ml and 1.24 g/ml. The heavier virus peak represented 43% of the recovered infectivity and could be enhanced. The light virus peak contained 26% of the infectivity and could not be enhanced. The density of enhancer was 1.20 g/ml and approximated the density of the light virus population.

Amnion↗
PubMed1971

Effect of host cell on distribution of a lysosomal enzyme during virus infection.

The time of appearance of a lysosomal enzyme, beta-glucuronidase, in the medium of cells infected with either measles virus or echovirus 6 varied with the host cell system. Replication and release of virus preceded leakage of beta-glucuronidase from green monkey kidney cells. In contrast, extracellular enzyme appeared before replication and release of virus in human amnion cells. Hydrocortisone depressed enzyme leakage but did not retard replication of measles virus or viral-induced cytopathology. The intracellular distribution of beta-glucuronidase in uninfected and measles virus-infected cells was also studied. Measles virus infection altered the position of particulate-bound beta-glucuronidase in linear sucrose gradients prior to substantial release of this enzyme intra- and extracellularly. At early stages in infection, most of the cell-associated virus banded with particulate-bound enzyme in the middle of the gradient. As infection progressed, separation of measles virus infectivity from enzyme activity occurred, and intracellular virus was recovered near the meniscus of sucrose gradients.

Amnion↗