Mapping the Relationship between Glycosyl Acceptor Reactivity and Glycosylation Stereoselectivity.

The reactivity of both coupling partners-the glycosyl donor and acceptor-is decisive for the outcome of a glycosylation reaction, in terms of both yield and stereoselectivity. Where the reactivity of glycosyl donors is well understood and can be controlled through manipulation of the functional/protecting-group pattern, the reactivity of glycosyl acceptor alcohols is poorly understood. We here present an operationally simple system to gauge glycosyl acceptor reactivity, which employs two conformationally locked donors with stereoselectivity that critically depends on the reactivity of the nucleophile. A wide array of acceptors was screened and their structure-reactivity/stereoselectivity relationships established. By systematically varying the protecting groups, the reactivity of glycosyl acceptors can be adjusted to attain stereoselective cis-glucosylations.

Predictive factors of postpartum fatigue: a prospective cohort study among working women.

OBJECTIVES: The aim of this study was to investigate which prepartum determinants contribute to the development of postpartum (PP) fatigue among working women in the Netherlands. METHODS: A prospective cohort study in 15 Dutch companies was conducted to measure different potential predictors using self-administrated questionnaires at baseline and at 30 weeks of pregnancy. Fatigue was measured at 12 (N=523) and 52 weeks (N=436) PP using the Checklist Individual Strength (CIS). A CIS score>76 was defined as fatigue. RESULTS: The prevalence of fatigue at 12 and 52 weeks PP was 24.5% and 18.1%, respectively. Fourteen predictive factors were found for fatigue (R(2)=0.37) at 12 weeks PP. Ten predictive factors were found for fatigue at 52 weeks PP (R(2)=0.36). In general, less favourable work relationships and characteristics, poorer mental health, more passive coping styles, more sleeping problems, more fatigue during pregnancy, and beliefs about child care arrangements were related to PP fatigue. At 30 weeks of pregnancy, only more fatigue (OR=3.69, p<0.001; OR=2.68, p=0.02) and poorer mental health (OR=0.50, p=0.02; OR=0.90, p=0.78) predicted fatigue both at 12 and 52 weeks PP. CONCLUSIONS: A large number of predictive factors for PP fatigue were found. These findings indicate that different aspects can contribute to being fatigued after pregnancy. Further research is needed to investigate the effect of possible interventions by employers and/or occupational physicians.