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Biomedical subjects

P R De Stasio

Publications and source records attributed to P R De Stasio.

6 recordsLinked to original sources
PubMed1990

Specific effect of interferon on the herpes simplex virus type 1 transactivation event.

Human recombinant gamma interferon and to a lesser extent alpha interferon were shown to inhibit herpes simplex virus type 1 replication in the human cell lines WISH and HEp-2. Dot blot analysis of viral DNA synthesis and viral RNA transcription indicated that the inhibition occurred at an early step in infection. A study of the early events after herpes simplex virus type 1 infection indicated that adsorption, penetration, uncoating, and transport of viral DNA were not affected by interferon. Northern (RNA) blot analysis revealed that both immediate-early and delayed-early gene transcription was inhibited by interferon. Transactivation of the immediate-early responsive element linked to a reporter gene (CAT or tk) was specifically inhibited by both classes of interferon. Our data would indicate that either the transactivating protein VP16 or the complex formed between VP16 and a host protein(s) is attenuated by interferon.

Animals↗
PubMed1989

Trans-activation of herpes simplex virus type 1 immediate early genes is specifically inhibited by human recombinant interferons.

The effect of human recombinant interferons (IFNs) alpha and gamma on the transcription of Herpes Simplex virus type-1 (HSV-1) immediate early (IE) genes has been studied. Human amniotic cells (WISH) were transfected with a chimaeric plasmid containing the regulatory region of the HSV-1 IE genes controlling the expression of a reporter gene (CAT). Subsequently cells were infected with live HSV-1 to trans-activate the IE sequences. When cell samples were treated with IFN alpha or IFN gamma prior to viral infection, transcription of the CAT gene was greatly inhibited.

Amnion↗
PubMed1989

In situ amplification of viral signal in infected samples applied directly to nitrocellulose membranes.

A method for the amplification of viral signal present in infected samples is described. Viral suspensions are spotted on nitrocellulose paper, and immediately afterwards an adequate amount of a permissive cell line is added. The nitrocellulose filter is then incubated overnight, fixed and hybridized to labeled viral probes. The technique is extremely fast, reproducible and inexpensive, and may be readily applicable to the clinical diagnosis of many viral diseases.

Biotechnology↗
PubMed1988

A fast and sensitive method for detecting specific viral RNA in mammalian cells.

A quick and sensitive method to quantitate viral RNA synthesis has been developed. Utilizing glutaraldehyde to fix infected cells onto nitrocellulose paper, viral RNA can be probed directly in situ. Viral message can be detected from as few as 10(4) infected cells. This technique can be used to study viral gene expression and can be adapted to screen the activity of antiviral agents such as interferon.

Animals↗
PubMed1985

Isolation and molecular cloning of a fast-growing strain of human hepatitis A virus from its double-stranded replicative form.

A fast-growing strain of human hepatitis A virus was selected and characterized. The virus has the unusual property of developing a strong cytopathic effect in tissue culture in 7 to 10 days. Sequences of the viral genome were cloned into recombinant plasmids with the double-stranded replicative form as a template for the reverse transcription of cDNA. Restriction analysis and direct sequencing indicate that this strain is different from that described by Ticehurst et al. (Proc. Natl. Acad. Sci. USA 80:5885-5889, 1983) in the region that presumptively codes for the major capsid protein VP1, but both isolates have conserved large areas of homology in the untranslated 5'-terminal sequences of the genome.

Animals↗