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F Ban

Publications and source records attributed to F Ban.

5 recordsLinked to original sources
PubMed2003

Epstein-Barr virus nuclear antigen-1 colocalizes with lamin B1 in the nucleoplasm and along the nuclear rim.

Epstein-Barr virus nuclear antigen 1 (EBNA-1) is essential for the maintenance of latent EBV plasmids, and is also a transcriptional regulator. Nuclear lamins, components of the nuclear lamina, have also been found in the nucleoplasm. We report here that EBNA-1 coincided with lamin B1 in the nucleoplasm and around the nuclear rim during S-phase by confocal microscopy of cells transfected with EBNA-1 in the absence of EBV plasmids. Lamin B1, which is rarely detected in nuclear soluble fractions, was detected in chromatin and nuclear matrix fractions of the EBNA-1-expressing cells. These observations suggest that EBNA-1 colocalizes with lamin B1 in the subnuclear sites.

Animals↗
PubMed2001

Modeling the action of an antitumor drug: a density functional theory study of the mechanism of tirapazamine.

Density functional theory methods are employed to investigate experimentally proposed mechanisms by which the antitumor drug tirapazamine may react with a DNA sugar-C(1)' radical to give the sugar derivative deoxyribonolactone, with concomitant DNA strand breakage. For the previously proposed minor pathway, ionization of the sugar-C(1)' radical by tirapazamine, the calculated ionization energy, and the electron affinity of the models of the sugar-C(1)' radical of DNA and tirapazamine suggest that tirapazamine must be protonated to be able to oxidize the sugar-C(1)' radical. The preferred mechanism for reaction of tirapazamine with a sugar-C(1)' radical, in agreement with experimental observations, is found to proceed by direct attack of an N-oxide oxygen of tirapazamine at the sugar-C(1)' position, followed by homolytic cleavage of the N-O bond of the drug moiety. Possible alternative mechanisms are also investigated.

Antineoplastic Agents↗
PubMed1992

Use of enzyme-linked immunosorbent assays with chimeric fusion proteins to titrate antibodies against Epstein-Barr virus nuclear antigen 1.

Two new enzyme-linked immunosorbent assays (ELISAs) with chimeric fusion polypeptides for the detection of human antibodies specific to Epstein-Barr virus nuclear antigen 1 (EBNA-1) are described. One is an indirect ELISA with affinity-purified beta-galactosidase-EBNA-1 fusion protein as the antigen. The other is a "sandwich" assay based on the use of anti-beta-galactosidase antibody to capture beta-galactosidase-EBNA-1 fusion proteins in bacterial extracts. A good correlation was shown between antibody titers determined by the ELISA with the EBNA-1 fusion proteins and those determined by a conventional anticomplement immunofluorescence test which is being widely performed with Raji cells for the purpose of research and clinical diagnosis. The advantage of the ELISAs for seroepidemiologic studies on Epstein-Barr virus was demonstrated by sensitive detection of marginal immunoglobulin G antibody to the EBNA-1 domain in serum samples from patients with infectious mononucleosis.

Antibodies, Viral↗