Cytokine-based Predictive Models to Estimate the Probability of Chronic Periodontitis: Development of Diagnostic Nomograms.

Although a distinct cytokine profile has been described in the gingival crevicular fluid (GCF) of patients with chronic periodontitis, there is no evidence of GCF cytokine-based predictive models being used to diagnose the disease. Our objectives were: to obtain GCF cytokine-based predictive models; and develop nomograms derived from them. A sample of 150 participants was recruited: 75 periodontally healthy controls and 75 subjects affected by chronic periodontitis. Sixteen mediators were measured in GCF using the Luminex 100™ instrument: GMCSF, IFNgamma, IL1alpha, IL1beta, IL2, IL3, IL4, IL5, IL6, IL10, IL12p40, IL12p70, IL13, IL17A, IL17F and TNFalpha. Cytokine-based models were obtained using multivariate binary logistic regression. Models were selected for their ability to predict chronic periodontitis, considering the different role of the cytokines involved in the inflammatory process. The outstanding predictive accuracy of the resulting smoking-adjusted models showed that IL1alpha, IL1beta and IL17A in GCF are very good biomarkers for distinguishing patients with chronic periodontitis from periodontally healthy individuals. The predictive ability of these pro-inflammatory cytokines was increased by incorporating IFN gamma and IL10. The nomograms revealed the amount of periodontitis-associated imbalances between these cytokines with pro-inflammatory and anti-inflammatory effects in terms of a particular probability of having chronic periodontitis.

Local differences in the Archbishopric of Santiago de Compostela (Galicia, Spain) in relation to the consanguinity structure, 1900-1979.

The microgeographic variability of consanguinity in the Archbishopric of Santiago de Compostela (Galicia) between 1900 and 1979 was studied. This Archbishopric covers 106 local councils integrated by 964 parishes, of which 677 (70.23%) were analyzed. Of the 307,094 marriages counted within this period, 15,739 corresponded to weddings between biologically related couples. Within the Archbishopric, eight geographical regions were considered: six coastal regions (Golfo Artabro, Bergantiños, Fisterra, Xallas, Santiago Oeste, and Rías Baixas) and two inland regions (Santiago Este and Terra de Montes). In order to evaluate the differences and similarities among them, the frequencies of all types of marriages (consanguineous and nonconsanguineous) were considered. First, a hierarchical grouping of the regions based on their chi-squared distances was performed. Then, in order to analyze relationships that are exclusively due to the structure of consanguinity, a correspondence analysis was performed and only the frequency of the different types of consanguineous marriages was taken into account. The results from both statistical analyses indicate special features of the Xallas region, both in the level of inbreeding (8.75%, the highest in the Archbishopric) and in the structure of consanguinity, for which a high proportion of uncle-niece marriages was found (6.22% of all consanguineous marriages). In all cases the structure of consanguinity provides informative nuances on the differences and similarities among population groups.

Reporting delay: a review with a simulation study and application to Spanish AIDS data.

To correct for the effect of reporting delay on incidence data relating to AIDS, three methods of estimation have been analysed: Poisson log-linear; log-linear logistic mixed regression (log-logit), and truncation. The first two methods transform the data in a contingency table. The difference between them is the hypothesis of delay stationarity, which is only assumed by the former. A correction is proposed for the first method to improve its asymptotic properties. The truncation method is based on the product-limit estimator. A simulation study was carried out to examine the behaviour (means, variances and mean squared errors) of the three methods. All were applied to data from the National Commission on AIDS (Spain), showing an improvement in reporting efficiency.