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Fifty-eight somatic hybrid plants, produced both by chemical (11) and electrical fusion (47) of protoplasts of dihaploid Solanum tuberosum and S. brevidens, have been analysed by molecular, cytological and morphological methods. The potentially useful euploid plants constituted 34% of the total, of which 20% were tetraploid and 14% hexaploid; the remainder were aneuploid at the tetraploid, hexaploid and octoploid levels. Analysis of chloroplast DNA showed that 55% of hybrids contained chloroplasts from S. brevidens and 45% from S. tuberosum. Hexaploids, the products of three protoplasts fusing together, were analyzed with specific DNA probes, and this revealed that nuclear genome dosages could be either 2∶1 S. tuberosum∶S. brevidens, or vice-versa. Chloroplast types of hexaploids were not influenced by nuclear genome dosage, and all six possible combinations of genome dosage and chloroplast types were found amongst tetraploids and hexaploids. To examine the morphology of the hybrid population and its possible relation to the chromosome number and chloroplast DNA type, 18 morphological characteristics were measured on greenhouse-grown plants and analyzed by principal component and canonical variate analyses. Both analyses showed that nuclear ploidy has the most prominent influence on the overall morphology of the hybrids. Differential parental genome expression in the morphology of the hybrids is discussed. These results provide useful data on the range of genetic combinations that can be expected to occur amongst somatic hybrid plants.

There is an increased risk of upper respiratory infection (URI) for the child compromised by Down Syndrome. Nurses can educate parents to care for the child experiencing mild URI without the need for medical intervention.

Phenylketonuria (PKU) is estimated to occur in 1 in 8,000 to 20,000 live births. Newborn screening identifies these children and proper dietary management changes the course of their lives from mental retardation to normal intelligence. However, there are many factors that influence whether the family and the person with PKU will cope satisfactorily with this lifelong condition. Interdisciplinary teams often assist the family and client with this process. As a member of the team the nurse assumes a counseling and teaching role. That role, following a developmental perspective, is presented in this article.

To determine the effects of diabetic ketoacidosis on the brain, we studied nine consecutive patients between the ages of 6 and 17 years by performing cranial CT on three occasions: on admission, before treatment; 6-8 hr after beginning treatment; and 7 days after admission. Both the pretreatment scans and those at 6-8 hr showed significantly reduced size of the lateral and third ventricles in comparison with the 7-day scans. A comparison of the pretreatment scans with those done at 6-8 hr showed no statistically significant differences. We conclude that the cerebral swelling of diabetic ketoacidosis is usually present before treatment.