No abstract

Multigene and non‐genic DNA families are in a state of turnover and hence are continually being replaced throughout a population by new variant repeats. To quantify such molecular processes, in the absence of selection, it is necessary to find and compare stages of transistion during the homogenization of at least two non‐genic families evolving in parallel in a closely related group of species. Detailed sequence analysis of patterns of variation, at each nucleotide position considered independently, amongst repeats of two tandem DNA families from seven related Drosophila species, reveals all stages of transition during the spread of randomly produced variant repeats. Variant repeats are found at different stages of homogenization and fixation in a population, irrespective of the loci, chromosomes or individuals from which they were cloned. Differences between the families in the relatively small number of variants at each transition stage and the greater number of fully homogenized and fixed variants between species of greater divergence indicate that the process of spread (molecular drive) is rapid relative to the mutation rate and occurs at seemingly different constant rates for each family. Occasional gene conversions, in addition to unequal exchanges, have contributed to family turnover. The significance of these results to the evolution of functional multigene families and divergence and conservation of sequences is discussed.

No abstract

OBJECTIVE—We evaluated the association of different types of educational visits for diabetic patients of the eight Philadelphia Health Care Centers (PHCCs) (public safety-net primary care clinics), with hospital admission rates and charges reported to the Pennsylvania Health Care Cost Containment Council. RESEARCH DESIGN AND METHODS—The study population included 18,404 patients who had a PHCC visit with a diabetes diagnosis recorded between 1 March 1993 and 31 December 2001 and had at least 1 month follow-up time. RESULTS—A total of 31,657 hospitalizations were recorded for 7,839 (42.6%) patients in the cohort. After adjustment for demographic variables, baseline comorbid conditions, hospitalizations before the diabetes diagnosis, and number of other primary care visits, having had any type of educational visit was associated with 9.18 (95% CI 5.02–13.33) fewer hospitalizations per 100 person-years and $11,571 ($6,377 to $16,765) less in hospital charges per person. Each nutritionist visit was associated with 4.70 (2.23–7.16) fewer hospitalizations per 100 person-years and a $6,503 ($3,421 to $9,586) reduction in total hospital charges. CONCLUSIONS—Any type of educational visit was associated with lower hospitalization rates and charges. Nutritionist visits were more strongly associated with reduced hospitalizations than diabetes classes. Each nutritionist visit was associated with a substantial reduction in hospital charges, suggesting that providing these services in the primary care setting may be highly cost-effective for the health care system.

No abstract