The disulfide exchange folding properties of insulin-like growth factor I (IGF-I) have been analyzed in a redox buffer containing reduced (10 mM) and oxidized (1 mM) glutathione. Under these conditions, the 3 disulfide bridges of the 70 amino acid peptide were not quantitatively formed. Instead, five major forms of IGF-I were detected, and these components were concluded to be in equilibrium as their relative amounts were similar starting from either reduced, native, or a mismatched variant of IGF-I containing two non-native disulfides. The different components in the mixtures were trapped by thiol alkylation using vinylpyridine and subsequently isolated by reverse-phase HPLC. The purified variants were further characterized using plasma desorption mass spectrometry and peptide mapping. Two of the five different forms were identified as native and mismatched IGF-I. One form was a variant with only one disulfide bond, and the other two major components had two disulfides formed. In a separate experiment, early refolding intermediates were trapped by pyridylethylation after only 90 s of refolding in the glutathione buffer, starting from reduced IGF-I. The intermediates were identical to the components observed at equilibrium, but at different relative concentrations. On the basis of the disulfide bond patterns of the different components in the equilibrium mixtures, we conclude that the disulfide between cysteines-47 and -52 in IGF-I is an unfavorable high-energy bond that may exist in the native molecule in a strained configuration.

No abstract

The present study is a part of a prospective, longitudinal investigation of caries development in children (n = 692) living in the southern suburbs of Stockholm. The aim was to evaluate, longitudinally, the caries-predictive ability of variables describing social and immigrant background, dietary habits, microbial and oral hygiene factors, and fluoride exposure in children at 1 and 2.5 years of age with respect to caries development before the age of 3.5. The predictors for caries development in children before 2.5 years of age were mutans streptococci (p < 0.01), immigrant background (p < 0.01), and consumption of candy (p < 0.01). The predictors for developing manifest caries between 2.5 and 3.5 years of age were mutans streptococci (p < 0.001), mother’s education (p < 0.001), immigrant background (p < 0.01), and consumption of candy (p < 0.05) and sugar-containing beverages (p < 0.05). The caries incidence at 2.5 years of age as well as the caries increment between 2.5 and 3.5 years of age were significantly higher in children with immigrant background compared to nonimmigrants. This study indicates that the possibility of identifying children at risk for caries development increases longitudinally from 1 to 3.5 years of age and there was a synergistic effect between age and each predictor.

This study indicated that EA to physical therapy resulted in greater improvement in perceived pain at 6 months compared to later access. In this study, EA to physical therapy could be introduced by reorganization without additional resources.

In an epidemiological study of the incidence of ulcerative colitis (UC) in the county of Stockholm between 1955Stockholm between and 1979Stockholm between , 1274 (p