Societies and Academies

Abstract

LONDON Royal Society, June 30. J. W. Cook, I. Hieger, E. L. Kennaway, and W. V. Mayneord: The production of cancer by pure hydrocarbons (1). Tests for cancer-producing action on mice are in progress, or have been completed, with preparations of the following polycyclic aromatic hydrocarbons composed entirely of benzene rings: (1) All the six possible four-ring compounds, (2) all the ten known compounds out of the fifteen possible five-ring compounds, (3) some compounds containing six and eight rings, and others. Some of the hydrocarbons examined are of very low solubility, and hence all tests carried out with them are unsatisfactory. No hydrocarbon in the pure state has produced cancers except 1:2:5:6-dibenzanthracene and some closely related compounds. It produced cancer of the skin when applied in a concentration of 0.003 per cent in benzene. J. W. Cook: The production of cancer by pure hydrocarbons (2). Preliminary results suggest that 6-iso-propyl-1: 2-benzanthracene is carcinogenic, and a pure sample of this has been synthesised and is being examined for carcinogenic activity, together with other iso-propyl and methyl derivatives of 1: 2-benz-anthracene. 5: 6 - cyclopenteno-1: 2-benzanthracene produced metastases in the axillary glands and lungs in four mice to which it was applied. There is evidence that a molecular structure consisting of new rings attached to the 1:2- and 5: 6- positions of the anthracene ring system is particularly efficacious in promoting carcinogenic activity. G. H. Eagles and A. H. H. Kordi: The cultivation of vaccinia virus: a new series of subcultures in cell-free medium. The cell-free medium has been prepared with the view of obtaining from adult rabbit kidney an extract rich in cell substance while eliminating the presence of actual cells. The medium must be freshly prepared. Vaccinia virus has been propagated in this medium through ten subcultures in one series, representing a multiplication of 1020 times the original culture with a dilution of 1017 of the virus content of the original culture. Though greater irregularity in growth occurs in cell-free medium than in medium containing living cells, experience has shown that with the former substantial yields of virus have been realised.