Isolates (657) representing 22 bacterial species were tested for susceptibility to silver sulfadiazine. All of the strains tested were inhibited by concentration levels of the drug which are easily achieved topically. It is suggested that silver sulfadiazine may be useful as a broad-spectrum antimicrobial substance for the prevention and treatment of infections of burns and wounds.

Two silver sulfadiazine-resistant isolates of Enterobacter cloacae obtained in a burns unit where the drug was in use were studied. These strains were resistant to elevated levels of the drug, and they were cross-resistant to silver benzoate, but not to silver nitrate. Growth of the strains in nutritionally poor defined media sensitized them to the inhibitory action of the drug. Exposure of the bacteria to penicillins rendered them susceptible to silver sulfadiazine. The resistant bacteria harbored episomes for resistance to carbenicillin and kanamycin; however, resistance to silver sulfadiazine could not be transferred by these episomes. Twenty-three strains of E. cloacae isolated in a general hospital were sensitive to much lower levels of the drug (≤50 μg/ml).

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causes a decrease in the phosphorylation product-ATP. This reduction in available free phosphate would be directly proportional to the reduction in total ATP produced.The amount of inhibition present in the cloacal bladder and intestinal mucosa of all species indicates that DDT may have a pronounced effect upon absorption of metabolites due to a lack of energy required for active transport across the cellular membrane. In this study there was marked inhibition of intestinal mucosa and cloacal bladder ATPase after in vitro treatment with 53 p M DDT. It is possible that treatment with equal concentrations of DDT in vivo would cause a serious inability to effectively utilize metabolites.The action of the lowest concentration (0.53 FLM) of DDT in the kidney of all species studied except Pseude m y s scripta resulted in low remaining (Na+ ,K+)-dependent ATPase activity. Assuming that the (Na-,K+)-dependent ATPase activity in the turtle kidney is similar in function to that of other vertebrates, the inability to reabsorb electrolytes from the glomerular filtrate due to enzyme inhibition by DDT may cause serious electrolyte imbalances.The observed action of DDT in all tissues assayed might be related to the i3bility of the compound to alter the cellular membrane configuration by binding with the fat por-tion of the membrane. Since ATPase is a structural part of the membrane, the active site of the enzyme would be altered. Movement of substances by active transport would be blocked. If the uptake of DDT by turtles in a natural environment reaches tissue concentrations equal to those found in this study, the resulting ATPase inhibition may be sufficient to impair organ function.Ethylene chlorohydrin (2-chloroethanol) is muta-ability to react with the DNA of living cells. In genic for Salmonella t y p h i m u r i u m in which mi-view of the possible presence of ethylene chlorcroorganism it induces mutations of the base-ohydrin in foodstuffs exposed to ethylene oxide, substitution type. This chemical also preferen-the potential hazard of human exposure to this tially inhibits the growth of DNA polymerase de-chemical requires examination. ficient bacteria which is taken to indicate an Ethylene oxide (EO) is widely used as a fumigant to sterilize foodstuffs,, textiles, medical instruments, and a variety of other objects (Merck Index, 1968; Fishbein, 1969). EO has wide applications in agriculture as a pesticide (Merck Index, 1968; Fishbein, 1969; Fishbein e t al., 1970) and in the tobacco industry to shorten the aging process and to reduce the nicotine content of tobacco leaves (see Fishbein, 1969; Fishbein e t al., 1970). The toxicity and mutagenic potential of EO are well recognized (Fishbein e t al., 1!370); however, because of its volatile nature, it has generally been assumed that EO was safe, not leaving a residue (see, however, Fishbein, 1969; Fishbein e t al., 1970). It has been found, however, that under conditions for effective fumigation, EO reacted with moisture and chloride ions to form ethylene chlorohydrin (...