The persistence of Staphylococcus aureus (Smith) on wool blanket, wool gabardine, cotton sheeting, cotton knit jersey, cotton terry cloth, and cotton wash-andwear fabrics was studied. The fabrics were exposed to bacterial populations by three methods: direct contact, aerosol, and a lyophilized mixture of bacteria and dust having a high content of textile fibers. The contaminated fabrics were held in 35 or 78%o relative humidities at 25 C. In general, the persistence time of S. aureus populations on fabrics held in 35% relative humidity was substantially longer when the fabrics were contaminated by exposure to aerosolized cultures or to dust containing bacteria than when contaminated by direct contact. In a 78% relative humidity, bacterial populations on the fabrics persisted for substantially shorter periods of time regardless of the mode of contamination or fabric type. Cotton wash-and-wear fabric (treated with a modified triazone resin) was the material on which populations of S. aureus persisted for the shortest time. This organism retained its virulence for Swiss mice after being recovered from wool gabardine swatches held 4 weeks in 35% relative humidity and 6 weeks in 78% relative humidity.

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trans-Tetrachloro-1,2-diaminocyclohexane platinum (IV) (tetraplatin) was therapeutically effective in mice bearing leukemia L1210 resistant (L1210/DDPt) or sensitive (L1210/0) to cis-diamminedichloroplatinum (II) (cisplatin). Furthermore, the sensitivity of cultured L1210/DDPt and L1210/0 cell populations to tetraplatin, cisplatin, and dichloro-trans-dihydroxyisopropylamine platinum (IV) (CHIP) was a function of the concentrations used for each compound. The relative degree of sensitivity between cultured L1210/DDPt and L1210/0 cells for each compound on the basis of the LC99 (the concentration of each compound required to reduce the number of viable cells by 99% in each cell line) was 3-fold for cisplatin, 2-fold for tetraplatin, and 3-fold for CHIP; thus the cultured L1210/0 cells exhibited a greater degree of sensitivity than the L1210/DDPt cells to the platinum compounds. The data indicate that if reduction of platinum IV compounds to platinum II compounds or metabolites is required for antitumor activity, then the cultured L1210 cells are capable of this bioreduction independently of any host factors.

The antihyperplastic activity of beta-retinoic acid (RA) and nine synthetic analogues (retinoids) was examined in organ cultures of mouse prostate made hyperplastic by treatment with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). After 8 or 10 days, when most explants developed hyperplasia, the carcinogen was withdrawn and explants were incubated in control medium and medium containing different concentrations of a retinoid. The antimitotic activity of retinoids was compared with that of RA. Different retinoids produced variable degrees of mitotic inhibition in the hyperplastic prostate epithelium. The methylketo cyclopentenyl and 1-methoxyethyl cyclopentenyl analogues of RA were at least 50-fold more active than RA in reversing MNNG-induced hyperplasia. The trimethylmethoxyphenyl analogue of RA and retinyl methyl ether were significantly more active than RA. Three analogues, N-acetyiretinylamine, retinal acetyl hydrazone, and retinal oxime, were as active as RA. The chlorotrimethylphenyl analogue showed less activity than RA, and alpha-retinyl acetate was completely devoid of mitotic inhibitory activity.

The persistence of Staphylococcus aureus (Smith) on wool blanket, wool gabardine, cotton sheeting, cotton knit jersey, cotton terry cloth, and cotton wash-and-wear fabrics was studied. The fabrics were exposed to bacterial populations by three methods: direct contact, aerosol, and a lyophilized mixture of bacteria and dust having a high content of textile fibers. The contaminated fabrics were held in 35 or 78% relative humidities at 25 C. In general, the persistence time of S. aureus populations on fabrics held in 35% relative humidity was substantially longer when the fabrics were contaminated by exposure to aerosolized cultures or to dust containing bacteria than when contaminated by direct contact. In a 78% relative humidity, bacterial populations on the fabrics persisted for substantially shorter periods of time regardless of the mode of contamination or fabric type. Cotton wash-and-wear fabric (treated with a modified triazone resin) was the material on which populations of S. aureus persisted for the shortest time. This organism retained its virulence for Swiss mice after being recovered from wool gabardine swatches held 4 weeks in 35% relative humidity and 6 weeks in 78% relative humidity.