Tumor-inducing properties of the mammary tumor agent in young and adult mice.
The mammary tumor-inducing activity of the mammary tumor agent was studied by the administration of either one or five injections of fractions of transplanted mammary cancer into mice ranging in age from 22 to 126 days.

The concentration of the fractions represented the amount of the agent derived from either 2 × 10-2 or 10-3 gm. equivalents of fresh tissue.

In general, the incidences observed in adult mice could not be correlated with the amount of the agent that was injected.

The highest incidence occurred in the progeny of the mice which received a single injection of the fraction with the lowest concentration of the agent.

The transmission of the agent was observed following the administration of the mammary tumor agent into both young and adult females.

No significant difference was to be seen in the transmission of the agent in the milk of either cancerous or noncancerous experimental mice.

Data were presented suggesting that the age resistance to the tumor-inducing action of the mammary tumor agent may be determined, in part, by the genetic constitution of the test animals. Other possibilities were discussed.
Mammary cancer in mice of different ages and stocks following the administration of the mammary tumor agent.
Summary Mammary cancer developed with the same incidence and at the same average cancer age in 22–24-day-old test animals following the injection of 5 × 10 -2 , 10 -3 , or 10 -4 gram-equivalents of a transplanted mammary carcinoma containing the mammary tumor agent (MTA). Lower incidences were observed in Zb, Ax, and F 1 mice injected at 133–154 days of age, yet the highest incidence was recorded in adult litter-mate ZBC mice which obtained the extract diluted 10,000-fold, and the differences were of statistical significance. In most groups, infection of the mothers and incidences and cancer ages seen in the progeny could not be correlated with the concentration of the agent in the extracts. The development of mammary cancer in the progeny of experimental females was influenced by the genetic constitution of the offspring but was not dependent upon the relationship of the mice to the original source of the MTA.
Synergistic Effect of High Temperature and High pH on the Destruction of Salmonella enteritidis and Escherichia co1i O157:H7.
This study was undertaken to determine if high temperature and high pH interact synergistically to enhance the rate of destruction of two important gram-negative foodborne pathogens, Escherichia coli O157:H7 and Salmonella enteritidis . The rates of destruction in NaHCO3-NaOH buffers at pH 7.0, 10.0, and 11.0 were determined at 35, 40, 45, 50, 55, 60, and 65°C. Use of an improved heating protocol eliminated a "tailing effect" at longer exposure times. The present study demonstrated that the combination of high pH and high temperature resulted in a highly significant synergistic interaction (P > F = 0.0001), which caused rapid death of both E. coli O157:H7 and S. enteritidis . This "alka-therm" technology might be used commercially to destroy gram-negative foodborne pathogens on various raw agricultural commodities.