The shrinking health advantage: unintentional injuries among children and youth from immigrant families

Abstract Background Immigrants typically arrive in good health. This health benefit can decline as immigrants adopt behaviours similar to native-born populations. Risk of injury is low in immigrants but it is not known whether this changes with increasing time since migration. We sought to examine the association between duration of residence in Canada and risk of unintentional injury. Methods Population-based cross-sectional study of children and youth 0 to 24 years in Ontario, Canada (2011-2012), using linked health and administrative databases. The main exposure was duration of Canadian residence (recent: 0–5 years, intermediate: 6–10 years, long-term: >10 years). The main outcome measure was unintentional injuries. Cause-specific injury risk by duration of residence was also evaluated. Poisson regression models estimated rate ratios (RR) for injuries. Results 999951 immigrants were included with 24.2% recent and 26.4% intermediate immigrants. The annual crude injury rates per 100000 immigrants were 6831 emergency department visits, 151 hospitalizations, and 4 deaths. In adjusted models, recent immigrants had the lowest risk of injury and risk increased over time (RR 0.79; 95% CI 0.77, 0.81 recent immigrants, RR 0.90; 95% CI 0.88, 0.92 intermediate immigrants, versus long-term immigrants). Factors associated with injury included young age (0-4 years, RR 1.30; 95% CI 1.26, 1.34), male sex (RR 1.52; 95% CI 1.49, 1.55), and high income (RR 0.93; 95% CI 0.89, 0.96 quintile 1 versus 5). Longer duration of residence was associated with a higher risk of unintentional injuries for most causes except hot object/scald burns, machinery-related injuries, non-motor vehicle bicycle and pedestrian injuries. The risk of these latter injuries did not change significantly with increasing duration of residence in Canada. Risk of drowning was highest in recent immigrants. Conclusions Risk of all-cause and most cause-specific unintentional injuries in immigrants rises with increasing time since migration. This indicates the need to develop strategies for maintaining the immigrant health advantage over time while balancing the desire to support integration, active living, and healthy child development

Identification and characterization of an auto-activating MEK kinase from bovine brain: Phosphorylation of serine-298 in the proline-rich domain of the mammalian MEKs

Mitogen-activated protein kinase kinases (MKKs or MEKs) are dual specificity tyrosine/threonine protein kinases that are activated by phosphorylation at two closely spaced serine residues (serines-218 and -222) by the c-mos and raf proto-oncogenes. This double phosphorylation is both necessary and sufficient for MEKs to activate the MAP kinase enzymes iii vitro. The specificity or regulation of in vivo signaling to the mammalian MEKs (MEK1 and MEK2) was recently reported also to involve the differential phosphorylation of a proline-rich peptide located between the MEK kinase-subdomains IX and X. Here we report the purification and characterization of an auto-activating protein kinase from bovine brain that phosphorylates serine-298 of the MEK1 and MEK2 proline-rich insert peptides. The auto-activation of the MEK-S298 peptide kinase is the result of an intermolecular phosphorylation el ent that can be prevented by the peptide substrate. The inactive kinase migrates on gel filtration as a 90 kDa protein, and after activation as a 43 kDa phosphoprotein. Incorporation of P-32[phosphate] into 40-42 kDa proteins on SDS-PAGE parallels the activation of the enzyme, and dephosphorylation by protein phosphatase 2Ac reverses the activation. SDS-PAGE renaturation assays show that the 40 kDa protein has the capacity to autophosphorylate, and exhibits kinase activity towards myelin basic protein after activation. Phosphorylation of purified bovine brain MEK or recombinant MEK1 by the auto-activated kinase does not activate the enzyme, and does not interfere with the in vitro raf-mediated MEK activation. We conclude that still unknown kinases may control the MAP kinase pathway by targeting MEK. (C) 1997 Elsevier Science Ltd

RAPID STIMULATION OF SER THR PROTEIN-KINASES FOLLOWING TREATMENT OF SWISS 3T3 CELLS WITH BOMBESIN - INVOLVEMENT OF CASEIN KINASE-2 IN THE SIGNALING PATHWAY OF BOMBESIN

Treatment of quiescent Swiss 3T3 mouse fibroblasts with bombesin resulted in a rapid 6-8-fold stimulation of cytosolic Ser/Thr kinase activities toward the S6 peptide (RRLSSLR), myelin basic protein (MBP), and the G peptide (SPQPSRRGSESSEE). Anion exchange Mono Q chromatography resolved multiple S6 peptide- and G peptide kinase activities and two MBP kinase peaks. Both MBP- and several S6 peptide kinase peaks could be inactivated by PCSL (PP2A2) phosphatase action. This indicates that the bombesin-induced activation of these enzymes is mediated by a Ser/Thr phosphorylation event. The S6 peptide kinases as well as the two MBP kinases stimulated in response to bombesin are similar to those activated by epidermal growth factor in Swiss 3T3 fibroblasts which suggests that the early events of the signal transduction pathway mediated by these growth factors in Swiss 3T3 cells may converge in the activation of common Ser/Thr kinases. Bombesin, which acts as a sole mitogen for Swiss 3T3 fibroblasts, also produced a several-fold increase in the kinase activity toward the RRREEESEEE peptide, a specific substrate for CK-2. This kinase activity was heparin-sensitive and also measurable with the G peptide (SPQPSRRGSESSEE) and GS-1 peptide (YRRAAVPPSPSPSLSRHSSPHQSEDEE), which contain consensus sequences for phosphorylation by CK-2. The bombesin-stimulated CK-2 activity could not be measured in whole cytosols but was revealed by the anion exchange chromatography step. The activation of CK-2 was not reversed by PCSL phosphatase action. The implication of CK-2 in the signal transduction pathway of bombesin is discussed