Cellular viability is usually determined by measuring the capacity of cells to exclude vital dyes such as 4',6-diamidino-2-phenylindole (DAPI), or by assessing nuclear morphology with chromatinophilic plasma membrane-permeant dyes, such as Hoechst 33342. However, a fraction of cells that exclude DAPI or exhibit normal nuclear morphology have already lost mitochondrial functions and/or manifest ...

The AT specific minor grove DNA binding ligands bisbenzimidazole derivatives like hoechst-33342 and hoechst-33258 which scavenge free radicals and stabilize macromolecular structure have been shown to afford radioprotection by reducing the induction of DNA damage. However, their ability to inhibit topoisomerases I & II, which play important roles in damage response pathways including DNA repair...

target of radiation action. The greatest toxicity is Purpose : The incubation of the DNA minor-groove binder observed when the I atom is incorporated within [I]iodoHoechst 33342 (IH) with plasmid DNA leads to the the DNA helix (i.e. 5-[I]iodo-2 3⁄4 -deoxyuridine, production of one double-strand break (dsb) per decay, both in IdUrd (Kassis et al. 1988)) , while its dislocation by the presence an...

It has been shown that polarity of environment around Hoechst 33342 is almost unchanged while sorption of this fluorescent dye on a surface of the hairpin oligonucleotide HP1, t-RNA and DNA. At small concentrations, this dye, adsorbed on the surface of DNA, RNA or HP1, does not show any specificity to certain nucleotides. In the case of unwound sites of DNA or HP1, it can bind inside, but witho...

Dedicated to Professor Gregorio Weber in the occasion of his 80th birthday It was found by investigating dichroism and emission anisotropy in the case of oneand two-photon excitation of Hoechst 33342 [bis-benzimide,2,5'-bi-lH-benzimidazole, 2'-(4-ethoxyphenyl)-5-5(4methyl-l-piperazinyl)] in stretched poly(vinyl alcohol) (PVA) films, that the absorption and fluorescence transition moments lie al...