Laboratory and field assessment of the molluscicidal activity of gogo (Entada phaseoloides) against the amphibious snail intermediate host of Schistosoma japonicum

A molluscicidal fraction occurs naturally in the bark of a vine (gogo in Tagalog), Entada phaseoloides, which grows indigeneously and abundantly in the Philippines. Butanol fraction of the methanol extracts of the bark was most toxic against Oncomelania quadrasi with the LC50 of 3.6-5.8 ppm. Analytical work on the butanol fraction by thin layer chromatography indicated that the active molluscicidal agents contained at least two kinds of saponins. The potency of E. phaseoloides remained rather stable over a wide range of pH values, in the presence of minerals and yeast cells and after ultraviolet irradiation of solutions. Our preliminary field trials, however, showed that doses as higher than 40 g per square meter would be needed to produce a satisfactory molluscicidal effect under field conditions.

[Metabolic fate of carteolol hydrochloride (OPC-1085), a new beta-adrenergic blocking agent. (6) Pharmacokinetics of carteolol in the rat, dog, rabbit and man]

The kinetics (absorption, distribution and excretion) of carteolol were investigated after oral and intravenous administration to man, rats, Beagle dogs and rabbits. The half-life of carteolol in plasma was 1.22 approximately 1.45 hr in rats, 1.73 approximately 2.08 hr in dogs and 1.42 approximately 1.43 hr in rabbits, and was independent of the route of administration. The absorption rate constants, obtained from log(C1-C) approximately time plot, after oral administration were 1.89 hr-1 in rats, 1.04 hr-1 in dogs and 1.54 hr-1 in rabbits. There were no differences between tablet and film coated tablet in the pharmacokinetic parameters of carteolol in man after oral 30 mg (tablet or film coated tablet) administration [half life (t1/2)=4.50 hr (tablet), 4.30 hr (film coated tablet), elimination rate constant (k2) equals 0.154 hr-1 (tablet), 0.161 hr-1 (film coated tablet)]. The elimination rate constant, obtained from Sigma-minus plot after 2, 5 and 10 mg oral administration, was 0.137 approximately 0.160 hr-1.

Tissue dispersion, cell harvest and fluid suspension culture by the use of bacterial neutral protease

Bacterial neutral protease of Bacillus polymyxa was found to disperse mammalian tissues and cells. Primary cell cultures were obtained from several tissues after treatments with 200 to 2,000 Kunitz unit per ml of this protease in either a phosphate buffer solution, a balanced salt solution or a tissue culture medium supplemented with serum. Monolayer cultures wither in their early passage levels or of established strains were harvested by a treatment with this protease, and proliferated again in monolayer after its removal. A growing culture of strain L-929 was kept in monodisperse suspension in the presence of this protease. In contrast to trypsin, this protease was found active in the presence of serum, stable during incubation and scarcely injured cells.