Effects of locoweed toxin on rats

Rats fed pellets containing locoweed developed typical microscopic lesions of locoweed poisoning. Rats fed a water extract of locoweed or urine from sheep given locoweed also developed microscopic lesions. This indicated that the locoweed toxin is water soluble and is excreted in the urine.     

Actinorhodin is a chromosomally-determined antibiotic in Streptomyces coelicolar A3(2)

Streptomyces coelicolar A3(2) synthesizes a second antibiotic, in addition to the plasmid-determined methylenomycin A. It was identified, primarily on the evidence of mass spectroscopy of its diethyl ester, as actinorhodin, which has been described previously in other strains. It inhibited most Gram-positive bacteria tested, but only at a comparatively high concentration. Five independent mutations leading to lack of actinorhodin synthesis were located between cysD and strA on the chromosome.     

The metabolic fate of the coronary vasodilator 4-(3,4,5-Trimethoxycinnamoyl)-1-(N-pyrrolidinocarbonylmethyl)piperazine (cinepazide) in the rat, dog and man

1. An oral dose of the coronary vasodilator 4-(3,4,5-trimethoxy[14C]cinnamoyl)-1-(N-pyrrolidinocarbonylmethyl)piperazine was well absorbed and more than 60% of the dose was excreted within 24 h. In 5 days, rats, dogs, and man excreted in the urine and faeces respectively 36.7% and 58.3%, 33.4% and 68.6%, and 61.3% and 38.1% dose. Faecal radioactivity was probably excreted via the bile. 2. Plasma concentrations of radioactivity reached a maximum within about 1 h in all three species and declined fairly rapidly (t0.5 less than 3 h). For several hours, more than 50% of the plasma radioactivity was due to unchanged drug. After correction for dose and body weight (normalization), peak plasma concentrations of unchanged drug in man, rat and dog were in the approximate ratio 100 :30:1. 3. Similar metabolites were excreted by the three species, but the relative proportions differed. Rats and man excreted 17.2% and 15.9% respectively as unchanged drug in the urine whereas dogs excreted only 3.6%. Rat bile and urine contained 4.3% and 9.8% dose respectively as glucuronides of the mono-O-demethylated compounds and dog and human urine contained 9.0% and 2.6% respectively of these metabolites. The corresponding pyrrolidone accounted for 2.5%, 5.5% and 5.1% respectively in rat, dog and human urine. Complete O-demethylation also occurred since 4-(3,4,5-trihydroxycinnamoyl)-1-(N-pyrrolidinocarbonylmethyl)piperazine was present in rat faeces (22.1% dose).     

The effect of paraben preservatives on albumin binding of bilirubin

The effect of sodium taurocholate in stepwise increasing infusion rates, 0.3 to 9.6 mumoles per min per kg, on the biliary excretion rate of iodipamide was investigated in 6 dogs (10 experiments) with complete bile diversion under general anesthesia. Iodipamide was administered intravenously with an initial priming dose of 33 mumoles per kg followed by a constant infusion of 1.3 mumoles per min per kg. Although the bile flow continuously increased with an increasing taurocholate dose, the iodipamide excretion rate reached a plateau with a 0.6 mumoles per min per kg of taurcholate infusion, which was 20% higher than with the lowest taurocholate dose. With a taurocholate dose over 2.4 mumoles per min per kg, a significant decrease in the iodipamide rate was found, amounting to 22% of its maximum value with the largest taurocholate dose. The bile iodipamide concentration was already at its maximum with the lowest taurocholate dose, and it decreased with an increasing taurocholate dose. Since the bile iodipamide concentration is probably the most important determinant in clinical cholangiography, low bile salt plasma levels should result in the best radiographic visualization of the biliary tree.     

Method of differential prognostication of pertussis morbidity

The authors present a method of differential prognostication of pertussis morbidity permitting to consider in prognostication the tendencies of individual subsets of the dynamic series which could be conditioned by individual causes. The general picture of the phenomenon to be prognosticated is obtained by superimposition of the values prognosticated by each of the segregated subsets.     

Prolonged retention of methyl mercury by mallard drakes

Mallard drakes accumulated mercury rapidly from dietary dosage of methylmercury dicyandiamide and eliminated it slowly, retaining approximately one half at the end of 84 days; no measurable loss occurred between the end of the 7th and 56th days, but loss resumed concurrently with new feather growth, and continued through the 112th day, the close of the study.