Long-term effects of an early home-based intervention.

OBJECTIVE: To evaluate the long-term effects of an early home-based intervention on the quantity and quality of psychiatric symptoms in adolescents. METHOD: The material consisted of 160 families with a baby born in 1975-1976. First, the families were classified with a weighted risk index into low- and high-risk families. Eighty families attended a 5-year-long family counseling program (10 times/year). The other half of the families served as a control group for the effects of counseling. The mental state of the adolescents was assessed at age 14 to 15 years by the Child Behavior Checklist and the Youth Self-Report. RESULTS: The adolescents in the counseling families scored significantly fewer total symptoms on both the parent and the youth reports. The counseling reduced more effectively internalizing than externalizing symptoms. The counseling predicted better mental health in adolescence in both low- and high-risk families. CONCLUSIONS: Home-based early intervention can have positive long-term effects on the mental state of adolescents. These results can be used when programs for primary prevention in families with small children are planned.

Expression of dicistronic transcriptional units in transgenic tobacco.

We investigated whether the two cistrons of a dicistronic mRNA can be translated in plants to yield both gene products. The coding sequences of various reporter genes were combined in dicistronic units, and their expression was analyzed in stably transformed tobacco plants at the RNA and protein levels. The presence of an upstream cistron resulted in all cases in a drastically reduced expression of the downstream cistron. The translational efficiency of the gene located downstream in the dicistronic units was 500- to 1,500-fold lower than that in a monocistronic control; a 500-fold lower value was obtained with a dicistronic unit in which both cistrons were separated by 30 nucleotides, whereas a 1,500-fold lower value was obtained with a dicistronic unit in which the stop codon of the upstream cistron and the start codon of the downstream cistron overlapped. As a strategy to select indirectly for transformants with enhanced levels of expression of a gene which is by itself nonselectable, the gene of interest can be cloned upstream from a selectable marker in a dicistronic configuration. This strategy can be used provided that the amount of dicistronic mRNA is high. If, on the other hand, the expression of the dicistronic unit is too low, selection of the downstream cistron will primarily give clones with rearranged dicistronic units.