conclusions this study supports the preventative effects of aminophylline on apnea in extreme premature infants. in other words, the more premature an infant, the greater the preventative effect of aminophylline on the incidence of apnea and bradycardia. background a few studies have been carried on preventive drugs for apnea of preterm neonates. objectives this study aimed to assess the safety...

1. Four 3-alkylxanthines (3-methylxanthine, 3-n-propylxanthine (enprofylline), 3-n-butylxanthine and 3-iso-butylxanthine) and four 1-methyl-3-alkylxanthines (1-methyl-3-methylxanthine (theophylline), 1-methyl-3-n-propylxanthine, 1-methyl-3-n-butylxanthine and 1-methyl-3-iso-butylxanthine (IBMX], were compared in terms of cyclic AMP phosphodiesterase (PDE) inhibition and trachealis muscle relaxa...

We obtained the electronic spectra of various methylated xanthine compounds including caffeine in a supersonic jet by resonant two-photon ionization spectroscopy. The methyl group in the tested methylated xanthine compounds has a distinct, site-dependent effect on the electronic spectrum. Methylation at the N3 position causes a significant red shift of the ππ* state, whereas methylation at the ...

INTRODUCTION Thiopurine therapy is often discontinued in inflammatory bowel disease (IBD) patients. The xanthine oxidase (XO) inhibitor allopurinol has previously shown to enhance thiopurine efficacy and to prevent adverse reactions, the mechanism of this beneficial interaction is not completely clarified. The aim of this study is to observe possible effects of allopurinol and low-dose thiopuri...

Two new potential pharmacologic therapies for recurrent stone disease are described. The role of hyperuricosuria in promoting calcium stones is controversial with only some but not all epidemiologic studies demonstrating associations between increasing urinary uric acid excretion and calcium stone disease. The relationship is supported by the ability of uric acid to "salt out" (or reduce the so...

The present study was to evaluate the two aminomethyl derivatives of dehydrozingerone: 5-[(4-methylpiperazin-1-yl)methyl]dehydrozingerone and 5-(morpholin-4-ylmethyl)dehydrozingerone as lipoxygenase xanthine oxidase inhibitors. Nordihydroguaiaretic acid, allopurinol parent compound dehydrozingerone were used comparative compounds. Results indicated that 5-[(4-methylpiperazin-1-yl)methyl] 5-(mor...

The systematic study of the substrate specificity of mammalian xanthine oxidase has indicated a common mechanism by which various purines may be dehydrogenated (1). The results obtained also made it clear why methylated xanthines, with the exception of 1-methylxanthine (2), cannot be oxidized by xanthine oxidase to the corresponding substituted uric acids (3, 4). Therefore, another source had t...

Differentiation therapy has been proposed as a new approach to selectively engage the process of tumor cell differentiation during chemotherapy of cancer. Our recent in vitro study suggests that such an approach can be extended and utilized for the selection of tumor-derived insulin-producing cells for transplantation. Repeated treatment with streptozotocin selected toxin resistant subpopulatio...

The electrochemical oxidation of 3,7-dimethylxanthine has been studied in the pH range 2.1–10.7 at pyrolytic graphite, platinum and glassy carbon electrodes. The electrooxidation of 3,7-dimethylxanthine at solid electrodes proceeds in a single 4e, 4H+ pH dependent step to give a diimine species which decomposes in chemical followup steps. The UV absorbing intermediate generated during electroox...