Radiosensitization by N-ethyl Maleimide–a Model Chemical System

A Study of Reactions of N-ethyl Malaeimide with Cellular Fractions during Radiosensitization ofE. ColiB/r

“…A similar result was obtained for phenylalanine. These results can be interpreted in terms of the following reactions as suggested also by Ward et al (1969) for thymine Whereas reaction (2) accounts for the protective effect of amino acids, reaction (3) explains the residual G(-NEM), at high amino acid concentrations .…”

“…G(-NEM)) was still noticed. The residual G(-NEM) has been attributed to the reaction of NEM with thymine-OH radicals (Ward, Johansen and Aasen 1969) . Since in our in vivo and in vitro studies NEM was found to be associated mainly with proteins rather than nucleic acids, it was of interest to investigate whether a similar reaction occurs with amino acids .…”

Chemical Radioprotection and Radiosensitization of Mammalian Cells Growingin Vitro

“…are believed to radiosensitize predominantly by the oxidation of cellular target radicals. NEM, although known to be capable of reacting with target molecules in an analogous manner (31)(32)(33), is thought to radiosensitize mammalian cells at extremely low concentrations (0.7 lM in Hank's balanced salts and 7 lM in complete medium) by an alternative mechanism. This mechanism could involve the oxidation of endogenous HD species [see (22,23)] and studies by Biaglow (34) may be extremely informative in elucidating whether a purely chemical reaction or biochemical alteration is involved.…”

A Modular Platform for the Rapid Site-Specific Radiolabeling of Proteins with 18F Exemplified by Quantitative Positron Emission Tomography of Human Epidermal Growth Factor Receptor 2

“…The dependence of [ 18 F]5 degradation on total radioactivity coupled with the formation of a broad spectrum of byproducts may indicate that [ 18 F]5 is susceptible to radiolysis which is characteristic for maleimide compounds. 40,41 Irrespective of the decomposition mechanism, the conjugation conditions were selected to maximize the reaction rate while ensuring that limited aggregates are formed. Considering the pH independence of the reactants' stability, basic conditions (pH 8) provided acceptable conjugation efficiency (30%) for 18 F-trastuzumab-ThioFab.…”