Colicin concentrations inhibit growth of Escherichia coli O157:H7 in vitro.

Escherichia coli O157:H7 is a virulent foodborne pathogen that causes severe human illness and inhabits the intestinal tract of food animals. Colicins are antimicrobial proteins produced by E. coli strains that inhibit or kill other E. coli. In the present Study, the efficacy of three pore-forming colicins (El, N, and A) were quantified in vitro against E. coli O157:H7 strains 86-24 and 933. Colicins E1 and N reduced the growth of E. coli O157:H7 strains, but the efficacy of each colicin varied among strains. Colicin E1 was more effective against both strains of E. coli O157:H7 than colicins A and N and reduced (P < 0.05) populations of E. coli O157:H7 at concentrations <0.1 microg/ml. These potent antimicrobial proteins may potentially provide an effective and environmentally sound preharvest strategy to reduce E. coli O157:H7 in food animals.

Children's response to acute pain: a developmental approach.

Pain in children is a major concern of health care providers. To adequately relieve children's pain, nurses and other health care providers must be able to determine when children of all developmental stages are experiencing pain. The purpose of this article is to review what is known about children's response to acute pain.

Fathering and the separation-individuation process.

Empirical evidence supports the belief that fathers play a significant role in the development of children. The father is becoming a more visible participant in physical care (feeding, diapering, and bathing) and the emotional life of the infant. Father-infant interactions have resulted in early formation of attachment to the father, but later than with the mother. Separation anxiety is reduced if the father-infant interactions have been qualitatively satisfactory to the infant. Father-infant interactions have a definite effect on the infant's progression through the separation-individuation process as described by Mahler and Abelin. The father's behavior toward the infant, particularly during the practicing subphase, enhances ego autonomy, differentiation, and individuation. According to Abelin, completion of the separation-individuation process may be impossible for the mother and the child if the father does not interact with the child. In view of this deduction, the writer concludes that special effort should be made by child and health care workers to encourage fathers' involvement with their very young children. Also, further investigation is needed in order to identify specific father-infant interactions that might facilitate the separation-individuation process.