No abstract

SINCE the Oxford workers (Abraham et al., 1941) suggested the agar cup assay method as a standard for the estimation of penicillin, great use of this method has been made. Many modifications have been suggested (McKee et al., 1944;Foster and Woodruff, 1943, 1944; 75 Lancet, ii, 177.

No abstract

With a Note on the Standardization of the Janus Green Milk Test SUMMARY: The isolation of faecal streptococci from the excreta of man, cattle and sheep was investigated. The methods compared were ( a ) heat, (b) tetrathionate, ( c ) tellurite, (d) thallium salts. The tellurite method proved highly efficient, isolating 97% of strains from human, cow and sheep faeces. A survey of the properties of strains isolated was made. Differential tests based on (a) heat resistance and (b) reducing properties were devised; these divided the streptococci isolated by the tellurite method into groups, some of which were characteristic of the source. The information available seems capable of distinguishing many strains obtained from man from those derived from cows or sheep, and it is suggested it may be of use in tracing sources of pollution in water, milk and other foodstuffs.

Bacterial pyrogen from S. abortus equi (SAE) was injected into the wing veins of chickens. Following injection of 0.05-0.5 mug SAE, body temperatures did not change significantly, whereas 2.0 or 10 mug of pyrogen caused falls in body temperature of 0.56 +/- 0.10degrees C and 1.1 +/- 0.21degrees C (mean +/- SE, n=5). The temperature falls were accompanied by a flushing of the comb and an increase in respiratory rate and were not antagonized by 1.0 g of acetylsalicylic acid (ASA) given orally. The injection of SAE (0.1 mug in 1 mul) into the anterior hypothalamus produced fevers averaging 1.24 +/- 0.07 degrees C (n=9) which were antagonized by oral ASA. Injections of SAE at other brainstem loci produced no temperatur changes. Seven chickens were also injected with 0.1 mug PGE in 1.0 mul into the anterior hypothalamus, and they developed fevers averaging 0.90 +/- 0.16 degrees C. The results support the concept that prostaglandins may be involved in fever in chickens but suggest that the action of pyrogen injected intravenously may be different from that following its injection directly into the hypothalamus.