Oral hypoglycemics and azoles: an important drug interaction.
Explore the source record for details and available documents.
SEARCH · Search PubMed
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The authors compared the in vitro antifungal activity of eight imidazole derivatives (clotrimazole, econazole, isoconazole, ketoconazole, miconazole, oxiconazole, terconazole, tioconazole) against 42 strains of Candida albicans by the agar dilution method using casitone medium. The geometric (G) mean MIC values, the MIC 90 and the MIC 50 values and the corresponding standard deviations of each antifungal agent were determined. The G-MIC values were found to be in the range of 0.008-0.390 micrograms ml-1. The effects of these eight antifungal agents on the ultrastructure of C. albicans yeast cells and spheroplasts were studied by scanning electron microscopy (SEM). The results showed a good correlation between the lesions observed and the structure of the imidazole derivatives tested. On the basis of the SEM results, the compounds could be divided into three groups: (1) ketoconazole and terconazole; (2) econazole, isoconazole, miconazole, oxiconazole and tioconazole; (3) clotrimazole.
Explore the source record for details and available documents.
The lanosterol 14 alpha-methyl demethylase inhibitors miconazole and ketoconazole have been used to assess their effects upon cholesterol biosynthesis in cultured Chinese hamster ovary cells. In Chinese hamster ovary cells treated with either agent, an initial accumulation of lanosterol and dihydrolanosterol has been observed. At elevated concentrations, however, ketoconazole, but not miconazole, causes the preferential accumulation of 24,25-epoxylanosterol and squalene 2,3:22,23-dioxide. These metabolites accumulate at the expense of lanosterol, thereby demonstrating a second site of inhibition for ketoconazole in the sterol biosynthetic pathway. Both demethylase inhibitors produced a biphasic modulation of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme in the cholesterol biosynthetic pathway. The biphasic modulation is characterized by low levels of the drugs suppressing HMG-CoA reductase activity which is restored to either control or above control values at higher drug concentrations. This modulatory effect of the lanosterol demethylase inhibitors upon HMG-CoA reductase was not observed in the lanosterol 14 alpha-methyl demethylase-deficient mutant AR45. Suppression of HMG-CoA reductase activity is shown to be due to a decrease in the amount of enzyme protein consistent with a steroidal regulatory mechanism. Collectively, the results establish that lanosterol 14 alpha-methyl demethylation, but not 24,25-epoxylanosterol formation, is required to suppress HMG-CoA reductase in the manner described by lanosterol demethylase inhibitors.
beta-(4-Pyrazole)acrylic acids 22-28 were prepared by the Knoevenagel reaction of malonic acid and 4-formylpyrazoles 8-14. 4-Pyrazolemethylenemalonic acids 15-21 were isolated as intermediates. The latter compounds were also synthesized by treating the 4-formylpyrazoles 8-14 with diethyl malonate followed by hydrolysis of the obtained diethyl esters 15a-21a. The effect of piperidine and pyridine on the Knoevenagel condensation was investigated. The beta-(4-pyrazole)acrylic acids 22-27, on catalytic reduction, gave the corresponding beta-(4-pyrazole)propionic acids 29-34. Compounds 23, 24, 27, 29-31 and 34 appeared to be less active than phenylbutazone in carrageenin-induced oedema test, but they were less toxic than the reference drug.
The authors describe a modified procedure for the synthesis of the 3-halogenindazole derivatives 1--7 and of the 1-hydroxymethylindazole derivatives 8--14. The compounds 8--13 yield the corresponding 1-chloromethyl derivatives 15--20, and 23 is obtained from 3. The compounds 7--23 exert slight antibacterial effects.
Explore the source record for details and available documents.
Two isolates of Candida albicans from chronic mucocutaneous candidosis patients who initially responded to ketoconazole treatment but who later relapsed, have shown an abnormal response to ketoconazole in four out of five systems in vitro and in three animal models of vaginal or systemic infection. They have also shown abnormal resistance to inhibition of ergosterol biosynthesis in whole cells, but not in cell-free systems, and to inhibition of amino acid uptake. We conclude that the behaviour of the isolates is consistent with the development of drug resistance to ketoconazole. In all systems the two isolates have shown cross-resistance to the triazole antifungal ICI 153,066. In addition they fail to take up radiolabelled ICI 153,066--in contrast to normal isolates--indicating that resistance is due to changes in the properties of the cell membrane rather than internal enzymology.
Morpholids, N-methylpiperazids, piperidids and pyrrolidids of 5-methyl, 3,5-dimethyl-1-phenyl-4-pyrazolthioacetic acid and 3,5-dimethyl-1-phenyl-4-pyrazolcarbonic acid 4-12 are obtained by the Willgerodt-Kindler procedure. The oxothioamids 13-19 result as the intermediate products of the synthesis of thioamids 4-10. The compounds 4, 5, 8, 9, 11, 14 and 17 do not respond to Mycobacterium tuberculosis H37Rv. The thioamids 4, 8 and 11 are of slight toxicity (LD50 greater than 2.8 g/kg, albino-Swiss mice) and inhibit the Carrageenin oedema of the Wistar rat claw minor than phyenylbutazon and indometacin.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The synthesis of water soluble hydrochlorides of indazole derivatives 1b, 8 and 9 is described. By treating of 2,5-dinitroindazole with thiomorpholine 3-thiomorpholino-5-nitroindazole (10) and 3,5-dinitroindazole (11) in the form of the molecular compound 11a are obtained. The known indazole derivatives 1 and 7 as well as the newly synthesized hydrochlorides of 1b, 8 and 9 are, except of 8.HCl, less toxic than benzydamine hydrochloric (BZD). The same compounds show with some excepts a comparable or greater antiinflammatory effect than BZD in the carrageenin induced oedema test.
A simple, reproducible and efficient assay was described for visual demonstration that triazole fluconazole interfered with the anti-Candida albicans activity of polyene amphotericin B. The assay also indicated the existence of more than one antifungal mechanism involving imidazole ketoconazole.