Хуудас 1 -аас 94 үр дүн
The role of the two-electron reducing enzyme DT-diaphorase in the activation of mitomycin C under hypoxic conditions was investigated. Mitomycin C activity was compared in L5178Y murine lymphoblasts, which have low levels of DT-diaphorase activity, and L5178Y/HBM10 cells, which have elevated levels
Changes in the production system of nitric oxide (NO), a multifunctional biological messenger known to participate in blood-flow regulation, neuromodulation, and neuroprotection or neurotoxicity, were investigated in the caudate putamen of adult rats submitted to hypobaric hypoxia. Employing
To study the regulation of the human detoxicating enzyme DT diaphorase (DTD) under hypoxic conditions, we examined the effects of heat and hypoxia, and their interaction, on the steady-state levels of mRNA and DTD enzyme activity in human colon adenocarcinoma HT29 cells. We found that a 1-h heat
Excitatory amino acids have been implicated in ischemic neuronal injury. To test this hypothesis in neonatal hypoxia-ischemia, lesions of the cortex and striatum were induced in 7-day-old rats by unilaterally ligating their carotid arteries and subjecting them to hypoxic conditions for 2 hours.
By light and electron microscope histochemical and cytochemical methods, the localization and activity of NADPH-diaphorase (NADPH-d) were studied in the central nervous system (CNS) of the chiton in control and after hypoxia. After acute hypoxia, the enzymatic activity increased in all regions of
The activity of the two-electron bioreductive enzyme DT-diaphorase (DTD) is induced by heat shock, hypoxic stress, oltipraz, and mitomycin C (MMC). Transcriptional induction is associated with nuclear factor binding to elements mediating immediate early response including AP-1, though the DTD mRNA
Twenty-three human tumour cell lines (lung, breast, and colon) and eight rodent cell lines were evaluated for their sensitivity to the quinone-based anticancer drug EO9 [3-hydroxymethyl-5-aziridinyl-1-methyl-2-(1H indole-4,7-dione)prop-beta-en-alpha-o1]. Sensitivity was compared with the
The diaziridiny/benzoquinone RH1 is shortly to enter a phase I clinical trial. The drug was originally designed as a substrate for the enzyme DT-diaphorase (DTD) such that metabolic activation of the drug would lead to toxicity. To evaluate this, we have measured the toxicity of RH1 in a pair of
OBJECTIVE
Although a number of bioreductive agents are substrates for purified DT-diaphorase the role of this enzyme in either activation or detoxification of these agents in the whole cell is unclear. The aim of this study was to determine the role of DT-diaphorase in the metabolic activation of
Several water-soluble derivatives (CPT3, CPT3a-d) of camptothecin (CPT) were synthesized, among which CPT3 bearing an N,N'-dimethyl-1-aminoethylcarbamate side-chain was further conjugated with reductively eliminating structural units of indolequinone, 4-nitrobenzyl alcohol and 4-nitrofuryl alcohol
Synthesis of nitric oxide (NO) has been shown in the glandular epithelium of human prostate, with highest levels in the peripheral zone. This location is believed to be the main source of prostatic cancer. The ability of stromal cells to produce NO may contribute to the malignant process. Since
The vulnerability of the developing CNS to hypoxia-ischemia (H-I) differs from that of the mature brain and is due in part to release of nitric oxide (NO) from parenchymal neurons. If NO is important in the generation of excitotoxic injury after H-I in the developing CNS, then selective destruction
Nitric oxide (NO) production in the sensory neurons of the rad nodose ganglion was studied by examining the distribuiotn of NO synthase (NOS) by use of NADPH diaphorase (NADPHD) histochemistry and immunohistochemistry ofr the presence of isoformes of NOS: neuronal (nNOS), endothelial (eNOS) and the
OBJECTIVE
To determine the dependency of the aerobic and hypoxic toxicity of tirapazamine on the intracellular activity of DT-diaphorase.
METHODS
A panel of 18 human cell lines comprising predominantly small cell and nonsmall cell lung cancer and breast cancer lines were used. The activity of