Ryna Karina Then

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The mode of action of sulfanilyl fluoroquinolones (NSFQs) was investigated with NSFQ-104, NSFQ-105, and some structurally related compounds. Evidence arising from interactions with p-aminobenzoic acid and trimethoprim suggested that a sulfonamidelike mechanism of action makes little or no contribution to the in vitro activity of NSFQs. NSFQ-105 showed an(More)
  • R Then
  • Zentralblatt für Bakteriologie, Parasitenkunde…
  • 1977
The thymidine content of a number of media now available commercially was determined, using Lactobacillus arabinosus ATCC 8014. The thymidine concentration in most liquid media was so high (greater than 0.01 microng/ml) that, without further treatment, these media could not be used for the testing of sulphonamides, trimethoprim or combinations thereof, more(More)
Two new series of dual-action antibacterial agents were synthesized in which penems and carbapenems were linked at the 2'-position to quinolones through either an ester or a carbamate moiety. Potent, broad-spectrum antibacterial activity was observed for both classes of compounds, indicative of a dual-mode of action.
During fermentation of glucose by the yeast Saccharomyces cerevisiae small amounts of acetaldehyde are formed. Anaerobically, acetaldehyde accumulates in the medium, showing only one maximum of ca. 10–30 mg/l in the logarithmic growth phase. During aerobic fermentation, acetaldehyde is formed in higher amounts (160 mg/l) and two maxima are observed. Both(More)