Purified Helicobacter pylori urease displayed a sigmoid curve in the plot of velocity versus [S] at urea concentrations less than 0.1 mM. Under conditions where preservatives, glycerol, or polyethylene glycol (PEG), were added to the enzyme reaction, the substrate hydrolysis was consistent with Michaelis-Menten kinetics, with a Km of 0.21+/-0.06 mM and a Vmax of 1200+/-300 micromol min(-1) mg(-...

An ascomycetes fungus was isolated from brine storage of green olives of the Arauco cultivar imported from Argentina and identified as Monascus ruber. The combined effects of different concentrations of sodium chloride (3.5-5.5%), sodium benzoate (0-0.1%), potassium sorbate (0-0.05%) and temperature (30-40°C) were investigated on the growth of M. ruber in the brine of stored table olives using ...

A reversed-phased HPLC method that allows the separation and simultaneous determination of the preservatives benzoic (BA) and sorbic acids (SA), methyl- (MP) and propylparabens (PP) is described. The separations were effected by using an initial mobile phase of methanol-acetate buffer (pH 4.4) (35:65) to elute BA, SA and MP and changing the mobile phase composition to methanol-acetate buffer (p...

A case-referent study was undertaken to look for occupational risk factors among patients with glioma treated in a neurological hospital in Paris between 1975 and 1984. In the study group were 125 men with gliomas (aged less than or equal to 65) and 238 patients (also less than or equal to 65) admitted for non-neoplastic, non-malformative vascular diseases in the same department during the same...