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Sodium [35S]sulphide was fed to batches of germinating rapeseed, in some instances with the addition of unlabelled cysteine. Both the total radioactivity and specific radioactivity of the free sulphur-containing amino acids were examined. Cysteine and homocysteine were rapidly labelled; label subsequently appeared in cystathionine and methionine. The results obtained indicated that both the sulphydration and trans-sulphuration pathways were operating. This conclusion was reinforced by the results of experiments in which batches of rapeseed were incubated with l-[14C]homoserine. These showed the formation of labelled homocysteine, cystathione and methionine. It was thought the trans-sulphuration pathway was making the greater contribution to the biosynthesis of methionine in germinating rapeseed.

• The course of rheumatic carditis in 100 patients treated with digitalis, salicylates, sedation, and symptomatic therapy was compared with its course in 55 patients treated with the hormones corticotropin, cortisone, and hydrocortisone.The three hormones were equally effective. In all patients so treated, the signs and symptoms of active carditis were arrested within 24 to 72 hours, and in the majority of patients enlarged chambers were reduced to normal and new precordial murmurs had regressed by the third to seventh day.A difference was found between the favorable results in the hormone-treated group and the protracted illness with residual cardiac damage seen in every patient in the contratest group. There was no overt evidence of residual damage in 84% of the patients who were having their first attack of carditis and who were treated with hormones.

In Escherichia coli, the nicotinamide moiety of pyridine nucleotides may be derived from de novosynthesis of the pyridine ring or through the uptake of either nicotinic acid or nicotinamide. De novosynthesis is the least preferred pathway; it is suppressed if an exogenous source is available. Nicotinamide is kinetically preferred over nicotinic acid; the data are consistent with the hypothesis that nicotinamide can pass through the bacterial membrane much faster than can the charged nicotinic acid, and once inside the cell, the amide is efficiently converted to the acid. Thus even at low concentrations nicotinamide is instantly taken up by cells, but at concentrations of less than 8 x10-6mnicotinic acid in the medium, the rate of entry of the nicotinic acid into the cell appears to be the rate-limiting step in the synthesis of pyridine nucleotide from exogenous niacin.

The swirling, incompressible flow within a short vortex chamber of aspect ratio 1/9, defined by the ratio of chamber height to chamber diameter, has been investigated analytically. The theoretical analysis consists of the adaptation of Wormley’s analytical technique and the extension of the method to include the apparent viscosity factor. The Runge-Kutta method is used to solve numerically the set of differential equations. The analytical results are compared with those of the experimental investigations conducted by Savino and Keshock. The analytical results prove that the values of apparent viscosity seriously affect the velocity profiles within the vortex chamber. The results also show that the apparent viscosity varies from 7000μ at the vortex chamber periphery to 4500μ at the orifice exit plane, where μ is the operating fluid viscosity. An empirical expression for the apparent viscosity is found in the form μa = K1νδn + K2, where n, K1, and K2 are constants and νδ is the tangential velocity. The constants n, K1, and K2 are found to be −1/3, 0.01, and 0.0005, respectively, for this investigation.

Following administration of his-tidine (imidazole-2-14C) to normal rats given pharmacological doses of cyanocobalamin the initial rate and amount of 14CO2excreted in the breath is significantly increased while in normal rats given pharmacological doses of folic acid these measurements are decreased as compared to normal untreated rats. These results indicate that pharmacological doses of cyanocobalamin increase and folic acid decrease either the rate of physical transport of histidine to intracellular sites of catabolism or the fractional rate describing the actual biochemical steps involved in such catabolism.

The chromosome number of the beet armyworm, Spodoptera exigua (Hübner), was determined as n=31 from larvae and adults from northern Florida reared on an artificial medium. All chromosomes are essentially spherical and similar in size.