Prevalence of caries and developmental defects of enamel in 9-10 year old children living in areas in Brazil differing water fluoride histories

Aims To assess the prevalences of caries, of developmental defects of enamel and their interrelationship in Brazilian 9-10-year-olds from areas of contrasting fluoridation histories.Methods systematic random sampling procedures were used to select children from an area where water had been fluoridated in 1963 and from a second area where water had been fluoridated since 1998. Clinical examinations for caries were carried out using the DMFT index and WHO diagnostic criteria. Developmental defects of enamel on upper incisors were diagnosed using the DDE index.Results A difference of 40% in DMFT was observed, with a lower prevalence of disease in the area fluoridated since 1963. Diffuse opacities affected 14.3% of the children from the area fluoridated since 1963 compared with only 2.4% in the area fluoridated in 1998. Children living in the area fluoridated in 1963 who had diffuse defects had twice the chance of being free from caries compared with those living in the same area who had no defects or who had only demarcated or hypoplastic defects.Conclusions This study confirms previous ones in showing the benefits of water fluoridation. Diffuse opacities of upper incisors affected relatively few subjects in either of the two areas.

Effect of Cervitec (R) on mutans streptococci in plaque and on caries formation on occlusal fissures of erupting permanent molars

The aim of this study was to evaluate the effect of Cervitec(R) on the abundance of mutans streptococci (MS) in occlusal dental plaque and on 2-year caries increment of partly erupting first permanent molars. Sixteen healthy schoolchildren aged 6-8 years, with at least 2 sound contralateral partly erupted permanent molars, received diet counselling and daily parental supervised toothbrushing with a fluoride dentifrice. Stimulated saliva samples were collected at baseline and after 1 year to evaluate MS levels. In a split-mouth design, Cervitec varnish was applied to one of the teeth at baseline and after 3 and 6 months, while the other tooth in the same jaw was a control. At the 9-month follow-up the teeth were in occlusal contact. At this time, varnish was not applied. At 3 and 6 months after the first application of varnish a significant suppression of MS was observed in plaque. Caries investigations, performed at baseline and every 3 months during the 2 years after the start of the study, showed that all the teeth treated with the varnish were free of caries after 2 years, whereas 8/16 control teeth developed incipient caries. In conclusion, our results suggest that treatment with Cervitec reduces MS in plaque on erupting permanent molars and can lead to a significant decrease in caries incidence. Copyright (C) 2002 S. Karger AG, Basel.

Response of Corriedale and Crioula Lanada sheep to artificial primary infection with Haemonchus contortus

Clinical, parasitological and biochemical parameters were evaluated in Corriedale and Crioula Lanada sheep after a single experimental infection with Haemonchus contortus. Ten 4-month-old worm-free lambs, of each breed, were infected with 200 L-3 H. contortus per kg live weight,and four uninfected animals of each breed were used as controls. Every week, the animals were weighed and blood and faecal samples were collected for measurement of packed cell volume (PCV), total serum protein (TSP) and albumin (ALB), and the number of eggs per gram of faeces (EPG), respectively. Twelve weeks after infection, the animals were slaughtered. The worm burden was determined and samples of the abomasal mucosa were processed for determination of the number of eosinophils, mast cells and globule leukocytes. No significant differences in PCV, TSP, ALB, parasite burden or the cell populations of the abomasal mucosa were observed between breeds, but Crioula lambs had a lower EPG count. The comparison of the infected groups with their respective controls revealed significant alterations in PCV, TSP and ALB in the Corriedale lambs and in PCV, TSP, ALB and the density of eosinophils and mast cells in the Crioula lambs.

MORPHOLOGY AND WEIGHT OF AFRICANIZED QUEEN BEES PRODUCED IN DIFFERENT DIAMETERS OF ARTIFICIAL, CUPS

The present work showed that the newly emerged queen weight, the number of ovarioles. and the spermatheca mass are not influenced by the sizes of the wax cups. The first two characters suffered time transference influence, and the best acceptances were obtained mainly, in wax cups with diameters of 7, 8, and 9 min.

APPLICATIONS OF ARTIFICIAL-INTELLIGENCE IN ORGANIC-CHEMISTRY .17. NEW PROGRAMS IN THE SISTEMAT PROJECT

This work describes the new improvements of the SISTEMAT project, one system for structural elucidation mainly in the field of Natural Products Chemistry. Some examples of the resolution of problems using C-13 Nuclear Magnetic Resonance and Mass Spectroscopy are given. Programs to discover new heuristic rules for structure generation are discussed. The data base contains about 10000 C-13 NMR spectra.