We describe a model for the evolutionary consequences of plasticity in an environmentally heterogeneous metapopulation in which specialists for each of two alternative environments and one plastic type are initially present. The model is similar to that proposed by Moran (1992) but extends her work to two sites. We show that with migration between sites the plastic type is favored over local specialists across a broad range of parameter space. The plastic type may dominate or be fixed even in an environmentally uniform site, and even if the plasticity has imperfect accuracy or bears some cost such that a local specialist has higher fitness in that site, as long as there is some migration between sites with different distributions of environmental states. These results suggest that differences among taxa in dispersal and hence realized migration rates may play a heretofore unrecognized role in their patterns of adaptive population differentiation. Migration relaxes the thresholds for both environmental heterogeneity and accuracy of plastic response above which plasticity is favored. Furthermore, small changes in response accuracy can dramatically and abruptly alter the evolutionary outcome in the metapopulation. A fitness cost to plasticity will substantially reduce the range of conditions in which the plastic type will prevail only if the cost is both large and global rather than environment specific.

Background: A healthy eating and exercise group for Asian women was established in April 1996. A community dietitian, fitness instructor and link worker took part in running the group and funding was provided by Trafford Healthcare NHS Trust and Trafford Metropolitan Borough Council. The group was run as a 14‐week pilot project, however, due to a positive response the group was continued. Aims: To follow up participants in the programme and examine their perceptions of the programme and changes in weight. Methods: Thirteen of the 15 overweight or obese women who attended the initial pilot group were followed up and qualitative evaluation was undertaken using a semistructured interview. Measurement of weight change was also made. Results: Formal methods of recruiting participants appear to have had little impact. Verbal recommendation of the group by the Link Worker and participants appear to have been effective routes for recruiting. Respondents suggested that the group fulfilled social and weight loss functions, both functions being interrelated and affecting weight. Important reasons for no longer attending the group seem to include difficulty getting to the venue and prioritization of the needs of the family over the women’s own needs. Conclusions: Some implications for the group are that women should be encouraged to walk to the group with others and it should be stressed that coming to the group and learning about healthy eating and exercise is important for the women’s health and also that of their families. Exercise was a popular aspect of the group and it is recommended that exercise sessions are held more frequently for a trial period. The resulting effects on attendance could then be assessed. All women could relate their weight change to diet and exercise in some way. The women who reported that they would definitely re‐attend the group were generally those with a higher BMI (body mass index).

We report on 11 patients (nine unrelated and a brother pair) with severe haemophilia A and factor VIII (FVIII) inhibitor, in whom immune tolerance (IIT) was induced with recombinant FVIII (r-FVIII). Their age ranged from 11 months to 47 years. The number of exposure days (ED) at inhibitor detection varied from 11 to 130. Nine of the 11 patients were high responders ¿>10 Bethesda units (BU) with peak inhibitor levels ranging from 10 to 566 BU. The other two were low responders with peak levels between 0.7 and 2 BU. Before inhibitor detection, the patients had been receiving products of various purities. The IIT regimens were very heterogeneous, and the treatment schedule varied from a short period with 50 IU kg-1 every 2 days, followed by 100 IU kg-1 every 2 days and then 220 IU kg-1 daily. The outcome was considered successful when the inhibitor level fell to 0.6 BU or lower after IIT treatment. The outcome overall was successful in nine out of 11 patients (81.8%), with the nine successful cases comprising seven of the nine high responders (77.8%) and the two low responders. Definite failure of IIT was observed in one high responder after two different IIT regimens. A second high responder is still on IIT treatment. All patients in whom IIT was successful are currently receiving r-FVIII on demand or prophylactically at various dosages. Despite the variability of the patient characteristics and the IIT schedules, this study demonstrates that r-FVIII represents an effective alternative for the eradication of inhibitors through IIT.

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