We synthesized a 5-fluorodeoxyuridine (5-FdUrd) derivative possessing an indolequinone structure (IQ-FdUrd) to characterize the radiolytic reduction in aqueous solution and the radiation-activated cytotoxicity against EMT6/KU cells under hypoxic conditions. IQ-FdUrd released antitumor agent 5-FdUrd upon hypoxic, but not aerobic, irradiation with the G value of 0.38 x 10(-7) mol J(-1). Laser flash photolysis of IQ-FdUrd in Ar-purged aqueous solution with dimethylaniline as an electron donor gave rise to a transient absorption spectrum characteristic of semiquinone radical anion, which decayed via second order kinetics. It is most likely that bimolecular disproportionation of intermediate semiquinone radicals occurs to release 5-FdUrd. IQ-FdUrd showed enhanced cytotoxicity against EMT6/KU cells in a radiation dose-dependent manner upon hypoxic irradiation. IQ-FdUrd is potentially a prototype compound for new class of radiation-activated antitumor prodrugs that are useful for radiation treatment of hypoxic tumors.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.bmcl.2005.03.013 | DOI Listing |
Int J Biochem Cell Biol
March 2024
Department of Pharmacology and Physiology, Oklahoma State University College of Osteopathic Medicine, Tahlequah, OK, USA.
Parkinson's disease (PD) is a neurodegenerative disorder that progresses over time and is characterized by preferential reduction of dopaminergic neurons in the substantia nigra. Although the precise mechanisms leading to cell death in neurodegenerative disorders, such as PD, are not fully understood, it is widely accepted that increased oxidative stress may be a prevalent factor contributing to the deterioration of the nigrostriatal dopaminergic fibers in such conditions. Aminochrome, generated from dopamine (DA) metabolism, plays an important role in multiple pathogenic mechanisms associated with PD.
View Article and Find Full Text PDFAntimicrob Agents Chemother
June 2023
Division of Infectious Diseases, SUNY Downstate Medical Center, Brooklyn, New York, USA.
The development of resistance to cefiderocol among multidrug resistant Acinetobacter baumannii has been attributed to downregulation in iron transport systems and a variety of β-lactamases. However, the precise contribution of each in clinical isolates remains to be determined. Sixteen clinical isolates with varying degrees of cefiderocol resistance were investigated.
View Article and Find Full Text PDFPhys Chem Chem Phys
April 2023
Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology, Institutsky Lane 9, Dolgoprudny, 141701, Moscow Region, Russia.
Eumelanin, the human skin pigment, is a poly-indolequinone material possessing a unique combination of physical and chemical properties. For numerous applications, the conductivity of eumelanin is of paramount importance. However, its hydration dependent conductivity is not well studied using transport-relaxation methods.
View Article and Find Full Text PDFInt J Pharm
April 2023
Department of Immunology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran. Electronic address:
In current study, a new remotely controlled drug delivery, radio-sensitizing, and photothermal therapy agent based on thioglycolic acid modified bismuth nanosheets is thoroughly evaluated. Bismuth nanosheets were synthesized using sodium borohydride (NaBH) and Tween 20 through low energy (400 W) sonication within 2 h. The resultant nanosheets were 40-60 nm in size and 1-3 atomic layers in thickness.
View Article and Find Full Text PDFFood Chem Toxicol
March 2023
Department of Biology, School of Natural Sciences, University of Patras, GR-26500, Rio, Patras, Greece. Electronic address:
This study investigated the phytochemical profile of Drimia numidica leaf methanolic extract, as well as its cyto-genotoxic and cyto/genoprotective potential against mitomycin C (MMC) mediated effects on healthy human lymphocytes. Photosynthetic pigments, trace elements, and secondary metabolites were estimated and/or identified in methanolic extract of mature leaves, and the latter was further used for assessing its in vitro biological effects on MMC-free and/or MMC-treated human lymphocytes (at low, non-toxic concentrations of 0.001 and 0.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!