AIM To determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs) of concurrent chemoradiotherapy and cetuximab in patients with non-resectable locally advanced esophageal cancer. PATIENTS AND METHODS Escalating doses of oxaliplatin every second week and daily tegafur/uracil were given concurrently with radiotherapy, 59.4 Gy in 33 fractions. Cetuximab was given on day 15 (...

Nonnucleoside reverse transcriptase (RT) inhibitors (NNRTIs) are important components of current combination therapies for human immunodeficiency virus type 1 (HIV-1) infection. In screening of chemical libraries, we found 6-azido-1-benzyl-3-(3,5-dimethylbenzyl)uracil (AzBBU) and 6-amino-1-benzyl-3-(3,5-dimethylbenzyl)uracil (AmBBU) to be highly active and selective inhibitors of HIV-1 replicat...

The nucleoside triphosphate pools of two cytidine auxotrophic mutants of Salmonella typhimurium LT-2 were studied under different conditions of pyrimidine starvation. Both mutants, DP-45 and DP-55, are defective in cytidine deaminase and cytidine triphosphate (CTP) synthase. In addition, DP-55 has a requirement for uracil (uridine). Cytidine starvation of the mutants results in accumulation of ...

It has been shown that uracil can be incorporated into ribonucleic acid of the normal rat tissues (2). However, this incorporation becomes significant only when the enzymes associated with the catabolism of uracil are saturated with their substrates. When thii is achieved, the incorporation of uracil into RNA increases with substrate concentration. At high concentrations the extent of incorpora...

Echinacoside (ECH) is one of the major active phenylethanoid glycosides (PEGs) in famous traditional Chinese medicine, Herba Cistanches. Although it has various bioactivities, such as antioxidation, neuroprotection, and hepatoprotection, knowledge about its metabolic fate is scant. In the present study, eight phase II metabolites, 3,4 -O-dimethyl-ECH-3 -O-beta-d-glucuronide (M1); 4,4 -O-dimethy...

Hydrolytic deamination of cytosine to uracil in DNA is increased in organisms adapted to high temperatures. Hitherto, the uracil base excision repair (BER) pathway has only been described in two archaeons, the crenarchaeon Pyrobaculum aerophilum and the euryarchaeon Archaeoglobus fulgidus, which are hyperthermophiles and use single-nucleotide replacement. In the former the apurinic/apyrimidinic...