10 research outputs found
Testing the DoseāResponse Specification in Epidemiology: Public Health and Policy Consequences for Lead
Statistical evaluation of the doseāresponse function in lead epidemiology is rarely attempted. Economic evaluation of health benefits of lead reduction usually assumes a linear doseāresponse function, regardless of the outcome measure used. We reanalyzed a previously published study, an international pooled data set combining data from seven prospective lead studies examining contemporaneous blood lead effect on IQ (intelligence quotient) of 7-year-old children (n = 1,333). We constructed alternative linear multiple regression models with linear blood lead terms (linearālinear dose response) and natural-logātransformed blood lead terms (log-linear dose response). We tested the two lead specifications for nonlinearity in the models, compared the two lead specifications for significantly better fit to the data, and examined the effects of possible residual confounding on the functional form of the doseāresponse relationship. We found that a log-linear leadāIQ relationship was a significantly better fit than was a linearālinear relationship for IQ (p = 0.009), with little evidence of residual confounding of included model variables. We substituted the log-linear leadāIQ effect in a previously published health benefits model and found that the economic savings due to U.S. population lead decrease between 1976 and 1999 (from 17.1 Ī¼g/dL to 2.0 Ī¼g/dL) was 2.2 times (149 billion). The Centers for Disease Control and Prevention action limit of 10 Ī¼g/dL for children fails to protect against most damage and economic cost attributable to lead exposure
Spatial clusters of gonorrhoea in England with particular reference to the outcome of partner notification: 2012 and 2013
Type 2 innate lymphoid cells control eosinophil homeostasis
Eosinophils are specialized myeloid cells associated with allergy and helminth infections. Blood eosinophils demonstrate circadian cycling, as described over 80 years ago,(1) and are abundant in the healthy gastrointestinal tract. Although a cytokine, interleukin (IL)-5, and chemokines such as eotaxins, mediate eosinophil development and survival,(2) and tissue recruitment,(3) respectively, the processes underlying the basal regulation of these signals remain unknown. Here, we show that serum IL-5 is maintained by long-lived type 2 innate lymphoid cells (ILC2) resident in peripheral tissues. ILC2 secrete IL-5 constitutively and are induced to co-express IL-13 during type 2 inflammation, resulting in localized eotaxin production and eosinophil accumulation. In the small intestine where eosinophils and eotaxin are constitutive,(4) ILC2 co-express IL-5 and IL-13, which is enhanced after caloric intake. The circadian synchronizer vasoactive intestinal peptide (VIP) also stimulates ILC2 through the VPAC2 receptor to release IL-5, linking eosinophil levels with metabolic cycling. Tissue ILC2 regulate basal eosinophilopoiesis and tissue eosinophil accumulation through constitutive and stimulated cytokine expression, and this dissociated regulation can be tuned by nutrient intake and central circadian rhythms